-Rock glaciers are developed at permafrost areas of periglacial environment in Tianshan Mountains [7,17]. Based on field surveying andair-photo interprestation, the paper discusses the shape, characteristics of supply...-Rock glaciers are developed at permafrost areas of periglacial environment in Tianshan Mountains [7,17]. Based on field surveying andair-photo interprestation, the paper discusses the shape, characteristics of supply area, formation conditions and environmental differentiations of rockglaciers at head area of Urmqi River (43°05'-43°08' N, 86°48’-86°53E) inKalawuchen Range and the head areas of Toudao River and Danangou River (43°30’-43°50’N, 85°00-85°30’E) in Yilanhabierga Rangu at ShawanCounty. Formation conditions and morphological characteristics of rockglaciers are studies in terms of topographic conditions, climate, compositionand age.展开更多
BACKGROUND : Some studies demonstrate that allogenic peripheral nerve segment embedded subcutaneously significantly reduce the infiltration of lymphocyte and decrease immunological reaction.OBJECTIVE : To observe th...BACKGROUND : Some studies demonstrate that allogenic peripheral nerve segment embedded subcutaneously significantly reduce the infiltration of lymphocyte and decrease immunological reaction.OBJECTIVE : To observe the gross shape, optical and electron microscope results of allogenic nerve segment in rats 2 weeks after subcutaneous embedment, and compare with subcutaneous emdedment of autologous nerve segment. DESIGN : A randomized and controlled experiment.SETTING : Department of Orthopaedics of Fifth People's Hospital of Zhengzhou; Department of Orthopaedics,First Hospital Affiliated to Chongqing Medical University.MATERIALS : Totally 30 adult healthy Wistar male rats, with body mass of (200±20) g, were enrolled. Ten rats were chosen as the donors of allogenic nerve transplantation. The other 20 rats were randomly divided into 2 groups: allogenic nerve embedment group and autologous nerve embedment group, with 10 rats in each one. JEM-1220 transmission electron microscope (Japan) and Olympus BX50 optical microscope (Japan) were used. METHODS : This experiment was carried out at the laboratory of Orthopaedic Department, Chongqing Medical University from October 2000 to April 2002. ① Sciatic nerve of donor rats for allogenic nerve transplantation was cut off at 5 mm distant from pelvic strait.15 mm sciatic nerve segment was chosen from lateral part as graft, allogenic nerve embedment group: 15 mm sciatic nerve form the donor rats was embedded in the posterior part of right legs. Autologous nerve embedment group: 15 mm sciatic nerve segment of autologous left side was embedded in the posterior side of right legs. ② Nerve segment embedded subcutaneously was taken out at postoperative 2 weeks and performed gross observation; then 5 samples chosen randomly respectively from 2 groups and given haematoxylin-eosin staining and observation under optical microscope (×400);The other 5 samples were made into ultrathin sections (0.5μm)and observed under transmission electron microscope(×17 000). MAIN OUTCOME MEASURES : Gross shape, optical and electron microscope results of nerve segments of rats between two groups at 2 weeks after subcutaneous embedment. RESULTS : ① Results of gross observation: Appearance of nerve segment was similar between 2 groups. ② Results of optical observation: medullary sheath denaturation, axonotmesis, vascular engorgement, desmoplasia of adventitia and infiltration of inflammatory cells were all found in both 2 groups. Inflammatory reaction was a little more severe in the allogenic nerve embedment group than in the autologous nerve embedment groups.③Results of electron microscope : Similar cataplasia and denaturation of medullary sheath and cataplasia of Schwann cell were all found in the 2 groups. CONCLUSION: Some inflammatory reaction occurs after allogenic nerve embedment, but the activity of Schwann cell is similar to that of peripheral nerve after autologous nerve embedment.展开更多
Clinical Study and automatic diagnosis of electrocardiogram(ECG)data always remain a challenge in diagnosing cardiovascular activities.The analysis of ECG data relies on various factors like morphological features,cla...Clinical Study and automatic diagnosis of electrocardiogram(ECG)data always remain a challenge in diagnosing cardiovascular activities.The analysis of ECG data relies on various factors like morphological features,classification techniques,methods or models used to diagnose and its performance improvement.Another crucial factor in themethodology is howto train the model for each patient.Existing approaches use standard training model which faces challenges when training data has variation due to individual patient characteristics resulting in a lower detection accuracy.This paper proposes an adaptive approach to identify performance improvement in building a training model that analyze global trainingmethodology against an individual training methodology and identifying a gap between them.We provide our investigation and comparative study on these methods and model with standard classification techniques with basic morphological features and Heart RateVariability(HRV)thatmay aid real time application.This approach helps in analyzing and evaluating the performance of different techniques and can suggests adoption of a best model identification with efficient technique and efficient attribute set for real-time systems.展开更多
A critical component of dealing with heart disease is real-time identifi-cation,which triggers rapid action.The main challenge of real-time identification is illustrated here by the rare occurrence of cardiac arrhythm...A critical component of dealing with heart disease is real-time identifi-cation,which triggers rapid action.The main challenge of real-time identification is illustrated here by the rare occurrence of cardiac arrhythmias.Recent contribu-tions to cardiac arrhythmia prediction using supervised learning approaches gen-erally involve the use of demographic features(electronic health records),signal features(electrocardiogram features as signals),and temporal features.Since the signal of the electrical activity of the heartbeat is very sensitive to differences between high and low heartbeats,it is possible to detect some of the irregularities in the early stages of arrhythmia.This paper describes the training of supervised learning using features obtained from electrocardiogram(ECG)image to correct the limitations of arrhythmia prediction by using demographic and electrocardio-graphic signal features.An experimental study demonstrates the usefulness of the proposed Arrhythmia Prediction by Supervised Learning(APSL)method,whose features are obtained from the image formats of the electrocardiograms used as input.展开更多
Olfactory ensheathing cells(OECs) transplanted into the damaged spinal cord may be considered as a valuable remedy explorations for spinal cord repair. The proliferation of transplanted olfactory ensheathing cells dep...Olfactory ensheathing cells(OECs) transplanted into the damaged spinal cord may be considered as a valuable remedy explorations for spinal cord repair. The proliferation of transplanted olfactory ensheathing cells depends on various environmental factors and effective cues, which may include electrical fields(EFs). In this study, we investigated the proliferative capacity, morphologic alterations of olfactory ensheathing cells derived from neonate rat that occurd when exposed to two EFs of 20 Hz, 50 mV and20 Hz, 100 mV for 6 h. For both EF treatments, the MTT results revealed that the cellular proliferation of exposed group during the last 6 h of the experiment was statistically higher than that of control group. Then, we investigated morphological structure changes in the cells stained by Coomassie brilliant blue. Compared with control group, most of cells were present at intensively proliferating appearance including the microfilaments were long and thick and the accumulated appearance of cells. It is conceivable that electrical fields as a new approach may promote the growth and proliferation of OECs and may be engineered to control the survival of transplanted OECs in injured spinal cord.Although our results have been suggesting that EFs may be non-chemical strategies for cell proliferation, the fundamental mechanisms remain to be elucidated.展开更多
The morphological features of fish,such as the body length,the body width,the caudal peduncle length,the caudal peduncle width,the pupil diameter,and the eye diameter are very important indicators in smart mariculture...The morphological features of fish,such as the body length,the body width,the caudal peduncle length,the caudal peduncle width,the pupil diameter,and the eye diameter are very important indicators in smart mariculture.Therefore,the accurate measurement of the morphological features is of great significance.However,the existing measurement methods mainly rely on manual measurement,which is operationally complex,low efficiency,and high subjectivity.To address these issues,this paper proposes a scheme for segmenting fish image and measuring fish morphological features indicators based on Mask R-CNN.Firstly,the fish body images are acquired by a home-made image acquisition device.Then,the fish images are preprocessed and labeled,and fed into the Mask R-CNN for training.Finally,the trained model is used to segment fish image,thus the morphological features indicators of the fish can be obtained.The experimental results demonstrate that the proposed scheme can segment the fish body in pure and complex backgrounds with remarkable performance.In pure background,the average relative errors(AREs)of all indicators measured all are less than 2.8%,and the AREs of body length and body width are less than 0.8%.In complex background,the AREs of all indicators are less than 3%,and the AREs of body length and body width is less than 1.8%.2020 China Agricultural University.Production and hosting by Elsevier B.V.on behalf of KeAi.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).1.Introduction With the advancing of its scientific and technological capabilities,China has made great achievements in the mariculture.The production accounts for more than 70%of the world’s overall mariculture output[1].The measurement of body length,body width and other morphological features of fish have wide application prospects in smart mariculture.Due to the difference in the quality and feeding ability of the Juvenile fish,the growth of the fish in the same pond is significantly different after a period of growth.Then,the fish needs to be classified.Grading can make fish grow better and improve feed utilization[2].The fish body length and body width are closely related to the weight of the fish.In the mariculture,the fishermen judge the growth of the fish by collecting the morphological feature of the fish,and use the information as an important reference for feeding,fishing and classification[3].At present,most of the measurement methods of fish body morphological features are manual,the operator usesmeasuring ruler to measure manually.It requires high technical level,and has high labor intensity and low efficiency.Furthermore,https://doi.展开更多
Members of the Goliathus group in the order Coleoptera, family Scarabaeidae and the sub-family Cetoniidae is one among essential ecological insects worldwide with scanty documentation in Tanzania. The country was amon...Members of the Goliathus group in the order Coleoptera, family Scarabaeidae and the sub-family Cetoniidae is one among essential ecological insects worldwide with scanty documentation in Tanzania. The country was among the first point of collection of the specimen by Moser (1909) but subsequent attempts to locate and collect the specimen were unsuccessful possibly due to changed habitat and behaviour of Goliathus. Much of published work about the insect are based on the morphological characteristics of collected specimen which led to designation of six major species namely;Goliathus goliatus, G. cacicus, G. regius, G. albosignatus, G. orientalis and G. usambarensis, the last two being considered to exist in Tanzania. The current study reports on successful identification of habitats using biological cues and subsequently collected several Goliathus specimen that had been difficult to trace for more than a century. New insights into correct identity of the species by using a combination of morphological and molecular techniques have been set. The study has resolved that only one species, Goliathus orientalis with five sub-species exist in Tanzania.展开更多
Apriona germari larvae were obtained via sample collection in woodland and indoor rearing. In this study, larval instars were divided by Dyar's law, and the results showed that the larval stage of A. germari comprise...Apriona germari larvae were obtained via sample collection in woodland and indoor rearing. In this study, larval instars were divided by Dyar's law, and the results showed that the larval stage of A. germari comprised six instars, while the width of head capsule was the best instar-dividing structure. On the basis of instar division, tubercle numbers on the transverse furrow downside of first abdominal dorsal ambulatory ampullae, seta numbers of abdominal telson and lateral seta numbers of mandible were observed and statistically calculated. The accuracy of instar-dividing was verified by comparing with the Dyar's law. The coincidence rate of two instar-dividing results was 90. 47%. It is approved that the above morphological features could be used in instar division ofA. germari larvae.展开更多
A lunar geologic map at a scale of 1:5000000 was finished in the 1970s by the National Aeronautics and Space Administration, U.S U.S. Geological Survey. Department of the Interior, Till now, the landform classificati...A lunar geologic map at a scale of 1:5000000 was finished in the 1970s by the National Aeronautics and Space Administration, U.S U.S. Geological Survey. Department of the Interior, Till now, the landform classification system and lunar morphologic mapping have not been clarified. The work aims to put forward a new landform classification system and to obtain index and map in the Sheet H010. Some key morphologic features of lunar surface were compared with those of the Earth. This research is very important for whole lunar morphologic mapping and unraveling evolutionary progress.展开更多
Objective To develop a computer-aided diagnosis(CAD)system with automatic contouring and morphologic and textural analysis to aid on the classification of breast nodules on ultrasound images.Methods A modified Level S...Objective To develop a computer-aided diagnosis(CAD)system with automatic contouring and morphologic and textural analysis to aid on the classification of breast nodules on ultrasound images.Methods A modified Level Set method was proposed to automatically segment the breast nodules(46malignant and 60benign nodules).Following,16morphologic features and 17texture features from the extracted contour were calculated and principal component analysis(PCA)was applied to find the optimal feature vector dimensions.Fuzzy C-means classifier was utilized to identify the breast nodule as benign or malignant with selected principal vectors.Results The performance of morphologic features was 78.30%for accuracy,67.39%for sensitivity and 86.67%for specificity,while the latter was 72.64%,58.70%and 83.33%,respectively.After the combination of the two features,the result was exactly the same with the morphologic performance.Conclusion This system performs well in classifying the malignant breast nodule from the benign breast nodule.展开更多
Using the method of mathematical morphology,this paper fulfills filtration,segmentation and extraction of morphological features of the satellite cloud image.It also gives out the relative algorithms,which is realized...Using the method of mathematical morphology,this paper fulfills filtration,segmentation and extraction of morphological features of the satellite cloud image.It also gives out the relative algorithms,which is realized by parallel C programming based on Transputer networks.It has been successfully used to process the typhoon and the low tornado cloud image.And it will be used in weather forecast.展开更多
AIM: To predict the visual outcome in patients undergoing macular hole surgery by two novel three-dimensional morphological parameters on optical coherence tomography (OCT): area ratio factor (ARF) and volume ra...AIM: To predict the visual outcome in patients undergoing macular hole surgery by two novel three-dimensional morphological parameters on optical coherence tomography (OCT): area ratio factor (ARF) and volume ratio factor (VRF). METHODS: A clinical case series was conducted, including 54 eyes of 54 patients with an idiopathic macular hole (IMH). Each patient had an OCT examination before and after surgery. Morphological parameters of the macular hole, such as minimum diameter, base diameter, and height were measured. Then, the macular hole index (Mill), tractional hole index (THI), and hole form factor (HFF) were calculated. Meanwhile, novel postoperative macular hole (MH) factors, ARF and VRF were calculated by three-dimensional morphology. Bivariate correlations were performed to acquire asymptotic significance values between the steady best corrected visual acuity (BCVA) after surgery and 2D/3D arguments of MH by the Pearson method with two-tailed test. All significant factors were analyzed by the receiver operating characteristic (ROC) curve analysis of SPSS software which were responsible for vision recovery. ROC curves analyses were performed to further discuss the different parameters on the prediction of visual outcome. RESULTS: The mean and standard deviation values of patients' age, symptoms duration, and follow-up time were 64.8+8.9y (range: 28-81), 18.6+11.5d (range: 2-60), and 11.4+0.4mo (range: 6-24), respectively. Steady-post-BCVA analyzed with bivariate correlations was found to be significantly correlated with base diameter (r'0.521, P〈0.001), minimum diameter (r=0.514, P〈0.001), MHI (r -0.531, P〈0.001), THI (r=-0.386, P=-0.004), HFF (r=-0.508, P〈0.001), and ARF (r=-0.532, P〈0.001). Other characteristic parameters such as age, duration of surgery, height, diameter hole index, and VRF were not statistically significant with steady-post-BCVA. According to area under the curve (AUC) values, values of ARF, MHI, HFF, minimum diameter, THI, and base diameter are 0.806, 0.772, 0.750, 0.705, 0.690, and 0.686, respectively. However, Steady-post-BCVA analysis with bivariate correlations for VRF was no statistical significance. Results of ROC curve analysis indicated that the MHI value, HFF, and ARF was greater than 0.427, 1.027 and 1.558 respectively which could correlate with better visual acuity. CONCLUSION: Compared with MHI and HFF, ARF could effectively express three-dimensional characteristics of macular hole and achieve better sensitivity and specificity. Thus, ARF could be the most effective parameter to predict the visual outcome in macular hole surgery.展开更多
Automated grading of colon biopsy images across all magnifications is challenging because of tailored segmentation and dependent features on each magnification.This work presents a novel approach of robust magnificati...Automated grading of colon biopsy images across all magnifications is challenging because of tailored segmentation and dependent features on each magnification.This work presents a novel approach of robust magnification-independent colon cancer grading framework to distinguish colon biopsy images into four classes:normal,well,moderate,and poor.The contribution of this research is to develop a magnification invariant hybrid feature set comprising cartoon feature,Gabor wavelet,wavelet moments,HSV histogram,color auto-correlogram,color moments,and morphological features that can be used to characterize different grades.Besides,the classifier is modeled as a multiclass structure with six binary class Bayesian optimized random forest(BO-RF)classifiers.This study uses four datasets(two collected from Indian hospitals—Ishita Pathology Center(IPC)of 4X,10X,and 40X and Aster Medcity(AMC)of 10X,20X,and 40X—two benchmark datasets—gland segmentation(GlaS)of 20X and IMEDIATREAT of 10X)comprising multiple microscope magnifications.Experimental results demonstrate that the proposed method outperforms the other methods used for colon cancer grading in terms of accuracy(97.25%-IPC,94.40%-AMC,97.58%-GlaS,99.16%-Imediatreat),sensitivity(0.9725-IPC,0.9440-AMC,0.9807-GlaS,0.9923-Imediatreat),specificity(0.9908-IPC,0.9813-AMC,0.9907-GlaS,0.9971-Imediatreat)and F-score(0.9725-IPC,0.9441-AMC,0.9780-GlaS,0.9923-Imediatreat).The generalizability of the model to any magnified input image is validated by training in one dataset and testing in another dataset,highlighting strong concordance in multiclass classification and evidencing its effective use in the first level of automatic biopsy grading and second opinion.展开更多
In order to extract froth morphological feature,a bubble image adaptive segmentation method was proposed.Considering the image's low contrast and weak froth edges,froth image was coarsely segmented by using fuzzy ...In order to extract froth morphological feature,a bubble image adaptive segmentation method was proposed.Considering the image's low contrast and weak froth edges,froth image was coarsely segmented by using fuzzy c means(FCM) algorithm. Through the attributes of size and shape pattern spectrum,the optimal morphological structuring element was determined.According to the optimal parameters,some image noises were removed with an improved area opening and closing by reconstruction operation,which consist of image regional markers,and the bubbles were finely separated from each other by watershed transform.The experimental results show that the structural element can be determined adaptively by shape and size pattern spectrum,and the froth image is segmented accurately.Compared with other froth image segmentation method,the proposed method achieves much high accuracy,based on which,the bubble size and shape features are extracted effectively.展开更多
There is increasing evidence shows that programmed cell death (PCD) can occur underphysiological, pathological or stress conditions in plants. The present review describes themorphological and biochemical characterist...There is increasing evidence shows that programmed cell death (PCD) can occur underphysiological, pathological or stress conditions in plants. The present review describes themorphological and biochemical characteristics, physiological functions, and the research significance ofplant PCD in detail as well as makes comparison betWeen these aspects with those in animals. Inaddition, this paper is also making exploration of the possible pathway for signal transduction, geneticregulation of plant PCD, origin and evolution of PCD and proposes a tactic for research on plant PCDalthough it is still in a preliminary stage.Compared to PCD in animals, PCD in plants under various conditions has revealed much greaterdifference in morphological and biochemical characteristics, which presents different essence far fromthe definition of apoptosis of animals. Nevertheless, no inflammation, specific fragmentation of DNAand rise of the activities of endonuclease and protease in plant PCD are still typical hallmarks fordistinguishing PCD from necrosis. On view of molecular level, as in animals, PCD in plants is alsoregulated by specific genes and involves signal transduction pathway with the involvement of a varietyof signal molecules.The physiological functions of plant PCD are similar to those in animals too. In the importantphysiological and pathological processes in plants, i.e., during reproduction, development, growth,senescenced disease-resistance, and stress-resistance against adverse circumstance conditions, PCDtakes on functions as important as proliferation throughout the whole life cycle of living organisms.Obviously, the research on PCD in plants is of vital importance that should not be ignored either intheory or in agricultural production.At present, the research on PCD in plants is focusing on collecting morphological and biochemicalevidences. But many molecules of initiation signal participating in plant PCD have been identified andseveral genes directly related to this process were isolated, which provide useful enlightenment forillustrating signal transduction pathway of PCD. Moreover, some conserved signal molecules andregulating genes were found in plant PCD, and caspase-like proteases have been detected in HR celldeath as well as in development-associated PCD. These data provide strong evidence at molecular levelfor conservation and the origin and evolution of PCD.1 The authors want to extend the sincerely thanks to Prof. Michele C. Heath (University of Toronto, Canada),Prof. Niroo Fukuda (University of Tokyo, Japan), Prof. Duran L. Nooden (University of Michigan, USA),Prof. Chris Lamb (Salk institute, California), Prof. Sarah Hake (Agricultural Research Service, USA), Prof.David L. Vaux (The Walter and Eliza Hall insititue of Medical Research, Post Office Royal MelbourneHospital, Australia), Associate Prof. Jeffrey L. Dangl (University of North Carolina, USA), Associate Prof.Eric Lain (The State University of New Jersey, USA), Dr. Maki Katsuhara (Okayama University, Japan),Prof. Sarah Hake (AgricultUral Research Service, USA), Dr. Peter P. Repetti (University of California,USA), Da Blazena Koukalova (Academy of Sciences of the Czech Republic, CZ), Dr. Iona Weir(Horticulture and Food Research Institute of New Zealand, New Zealand), Dr. Thorsten Jabs (Institute forBiology III, Germany), Dr. Hong Wang (University of California, USA) and Dr. Patrick Gallois (Universityof Perpignan, France) for their kind providing their personal latest data of their research concerned andoffering academic exchanges with us.This project is granted by the National Natural Science Foundation of China (No. 39870423) and by StateCommission of Education, Doctorate Spot Foundation.Author for correspondence. E-mail: ycsong@whu.edu.cn.Evidences in various aspects indicate that PCD origins from prokaryote, and various forms of PCD arefound along the phylogenic tree.Conclusion: A variety of endogenous and exogenous signals can break the homeostasis within plantbody and result in differentiation, proliferation, quiescence, or death of cell at length展开更多
The goal of this study is to provide information on the process of pothole growth on a gorge streambed.Pothole geometries were measured in a reach of the Dabu river bed at the head of a gorge more than 200 m deeply in...The goal of this study is to provide information on the process of pothole growth on a gorge streambed.Pothole geometries were measured in a reach of the Dabu river bed at the head of a gorge more than 200 m deeply incising into a 650-750 m high planation surface formed in the middle Miocene in northern Guangdong,China.Geometric and derivative data of the potholes obtained from fieldwork were interpreted using standard statistical methodologies.Our study shows that the formation and development of a stream pothole were only related to local conditions of a stream reach where the pothole occurs;the weaknesses,which are usually intersect fractures,typically interconnected vertical joints,or triangular pits generated by hitting of rock fragments during floods,initiate the pothole development on a streambed;the geometrical dimensions of the potholes are controlled by tectonic joints developed in bedrock of the stream reach;the radius and the depth of potholes are strongly(log) positive correlated;the pothole shapes and the flow patterns are inconstant during pothole growth;a pothole can be formed within a short period,but cannot be fully developed and maintained for a long time in a strong incision streambed.The finding in our study can improve the understanding of Quaternary environment in Guangdong.展开更多
BACKGROUND Magnetic resonance imaging(MRI)is currently the standard investigation for suspected perianal diseases.Carcinoma arising from anal fistula is very rare,and early diagnosis is often difficult.AIM To describe...BACKGROUND Magnetic resonance imaging(MRI)is currently the standard investigation for suspected perianal diseases.Carcinoma arising from anal fistula is very rare,and early diagnosis is often difficult.AIM To describe and summarize the MRI findings of carcinoma arising from anal fistula.METHODS In this retrospective study,records of ten patients diagnosed with carcinoma arising from anal fistula and confirmed by surgery(n=7)or biopsy(n=3)between June 2006 and August 2018 were analyzed.All patients underwent preoperative pelvic MRI.Morphologic features,signal characteristics,fistula between the mass and the anus,contrast enhancement of mass,signal and enhancement of peritumoral areas,and regional lymphadenopathy were assessed.RESULTS All ten tumors were solitary(8 mucinous adenocarcinomas and 2 adenocarcinomas).The maximum diameter of the tumors ranged from 3.4 cm to 12.4 cm(median:4.15 cm;mean:5.68 cm).Eight patients had a fistula between the mass and the anus.Contrast enhancement of the peritumoral areas was noted in three(3/5)patients.Perirectal or inguinal lymphadenopathy was noted in seven patients.Most lesions of mucinous adenocarcinoma were multiloculated and cauliflower-like,with a thin capsule and focally unclear boundary.They were markedly hyperintense on fat-suppressed T2WI,slightly hyperintense with focal hyperintensity on diffusion-weighted imaging(DWI),and hyperintense with focal hypointensity on apparent diffusion coefficient(ADC)map,with progressive mesh-like contrast enhancement.Adenocarcinomas had an infiltrative margin without a capsule and appeared heterogeneously hyperintense or slightly hyperintense on fat-suppressed T2WI,hyperintense on DWI,and hypointense on ADC map,with persistent heterogeneous enhancement.CONCLUSION Our study highlighted several characteristic and potentially helpful MRI findings to diagnose carcinomas arising from anal fistula.展开更多
The dynamical processes of a typical linear dune including morphological features, dune ridge swing range and crest height were investigated at different monitoring periods in the hinterland of Tengger Desert. The res...The dynamical processes of a typical linear dune including morphological features, dune ridge swing range and crest height were investigated at different monitoring periods in the hinterland of Tengger Desert. The results indicated that the development of linear dune depends on not only the northwesterly prevailing wind, but also the winds from northeast and southwest. The dune ridge swayed along its fundamental strike and took on an eastward movement gradually. The original dune strike was NW70° on August 3, 1994, and then changed to NE15° on April 21, 2001. The dune crest increased by 1.8 m longitudinally, which manifested strong wind-blown sand activities in this region. Wind erosion frequently occured at the bottom of sand dune, while sand accumulation appeared on its mid-upper section. The mean wind erosion depth was 25 cm on the bottom of linear dune and the height difference of the control points on the dune’s ridge was 1.13 m. Although the linear dune swayed laterally, the horizontal displacement of its ridge moved eastward 5.8 m averagely. The swing range of the dune crest line is very distinct, with a maximum value of 13.2 m. The highest site on the K-profile swayed on both sides of the dune ridge and the heights were 19.88 m at the control point K5, 19.61 m at K6 and 19.05 m at K7, respectively. The results indicated that the lateral swing of the linear dune was distinct under the northwesterly wind and it moved toward east gradually.展开更多
In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crysta...In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crystals, dendritic growth, secondary nucleation, etc. Those phenomena possibly resulted from two factors: (1) partial temperature gradient, which is caused by heat asymmetry in the electrical resistance furnace, when crystals crystalize from silicate melt; (2) constitutional supercooling near the surface of crystals. The disparity of disequilibrated crystallization phenomena in different main crystalline phases causes various morphological features of the crystal aggregates. At the same time, disequilibrated crystallization causes great stress retained in the crystals, which results in cracks in glazes when the temperature drops. According to the results, the authors analyzed those phenomena and displayed correlative figures and data.展开更多
Baseline wander is a common noise in electrocardiogram (ECG) results.To effectively correct the baseline and to preserve more underlying components of an ECG signal,we propose a simple and novel filtering method based...Baseline wander is a common noise in electrocardiogram (ECG) results.To effectively correct the baseline and to preserve more underlying components of an ECG signal,we propose a simple and novel filtering method based on a statistical weighted moving average filter.Supposed a and b are theminimum and maximum of all sample values within a moving window,respectively.First,the whole region [a,b] is divided into M equal sub-regions without overlap.Second,three sub-regions with the largest sample distribution probabilities are chosen (except M<3) and incorporated into one region,denoted as [a 0,b 0 ] for simplicity.Third,for every sample point in the moving window,its weight is set to 1 if its value falls in [a 0,b 0 ];otherwise,its weight is 0.Last,all sample points with weight 1 are averaged to estimate the baseline.The algorithm was tested by simulated ECG signal and real ECG signal from www.physionet.org.The results showed that the proposed filter could more effectively extract baseline wander from ECG signal and affect the morphological feature of ECG signal considerably less than both the traditional moving average filter and wavelet package translation did.展开更多
文摘-Rock glaciers are developed at permafrost areas of periglacial environment in Tianshan Mountains [7,17]. Based on field surveying andair-photo interprestation, the paper discusses the shape, characteristics of supply area, formation conditions and environmental differentiations of rockglaciers at head area of Urmqi River (43°05'-43°08' N, 86°48’-86°53E) inKalawuchen Range and the head areas of Toudao River and Danangou River (43°30’-43°50’N, 85°00-85°30’E) in Yilanhabierga Rangu at ShawanCounty. Formation conditions and morphological characteristics of rockglaciers are studies in terms of topographic conditions, climate, compositionand age.
文摘BACKGROUND : Some studies demonstrate that allogenic peripheral nerve segment embedded subcutaneously significantly reduce the infiltration of lymphocyte and decrease immunological reaction.OBJECTIVE : To observe the gross shape, optical and electron microscope results of allogenic nerve segment in rats 2 weeks after subcutaneous embedment, and compare with subcutaneous emdedment of autologous nerve segment. DESIGN : A randomized and controlled experiment.SETTING : Department of Orthopaedics of Fifth People's Hospital of Zhengzhou; Department of Orthopaedics,First Hospital Affiliated to Chongqing Medical University.MATERIALS : Totally 30 adult healthy Wistar male rats, with body mass of (200±20) g, were enrolled. Ten rats were chosen as the donors of allogenic nerve transplantation. The other 20 rats were randomly divided into 2 groups: allogenic nerve embedment group and autologous nerve embedment group, with 10 rats in each one. JEM-1220 transmission electron microscope (Japan) and Olympus BX50 optical microscope (Japan) were used. METHODS : This experiment was carried out at the laboratory of Orthopaedic Department, Chongqing Medical University from October 2000 to April 2002. ① Sciatic nerve of donor rats for allogenic nerve transplantation was cut off at 5 mm distant from pelvic strait.15 mm sciatic nerve segment was chosen from lateral part as graft, allogenic nerve embedment group: 15 mm sciatic nerve form the donor rats was embedded in the posterior part of right legs. Autologous nerve embedment group: 15 mm sciatic nerve segment of autologous left side was embedded in the posterior side of right legs. ② Nerve segment embedded subcutaneously was taken out at postoperative 2 weeks and performed gross observation; then 5 samples chosen randomly respectively from 2 groups and given haematoxylin-eosin staining and observation under optical microscope (×400);The other 5 samples were made into ultrathin sections (0.5μm)and observed under transmission electron microscope(×17 000). MAIN OUTCOME MEASURES : Gross shape, optical and electron microscope results of nerve segments of rats between two groups at 2 weeks after subcutaneous embedment. RESULTS : ① Results of gross observation: Appearance of nerve segment was similar between 2 groups. ② Results of optical observation: medullary sheath denaturation, axonotmesis, vascular engorgement, desmoplasia of adventitia and infiltration of inflammatory cells were all found in both 2 groups. Inflammatory reaction was a little more severe in the allogenic nerve embedment group than in the autologous nerve embedment groups.③Results of electron microscope : Similar cataplasia and denaturation of medullary sheath and cataplasia of Schwann cell were all found in the 2 groups. CONCLUSION: Some inflammatory reaction occurs after allogenic nerve embedment, but the activity of Schwann cell is similar to that of peripheral nerve after autologous nerve embedment.
基金The authors extend their appreciation to King Saud University for funding this work through Researchers Supporting Project Number(RSP-2021/387),King Saud University,Riyadh,Saudi Arabia.
文摘Clinical Study and automatic diagnosis of electrocardiogram(ECG)data always remain a challenge in diagnosing cardiovascular activities.The analysis of ECG data relies on various factors like morphological features,classification techniques,methods or models used to diagnose and its performance improvement.Another crucial factor in themethodology is howto train the model for each patient.Existing approaches use standard training model which faces challenges when training data has variation due to individual patient characteristics resulting in a lower detection accuracy.This paper proposes an adaptive approach to identify performance improvement in building a training model that analyze global trainingmethodology against an individual training methodology and identifying a gap between them.We provide our investigation and comparative study on these methods and model with standard classification techniques with basic morphological features and Heart RateVariability(HRV)thatmay aid real time application.This approach helps in analyzing and evaluating the performance of different techniques and can suggests adoption of a best model identification with efficient technique and efficient attribute set for real-time systems.
基金The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work under Grant Number(R.G.P1/155/40/2019)。
文摘A critical component of dealing with heart disease is real-time identifi-cation,which triggers rapid action.The main challenge of real-time identification is illustrated here by the rare occurrence of cardiac arrhythmias.Recent contribu-tions to cardiac arrhythmia prediction using supervised learning approaches gen-erally involve the use of demographic features(electronic health records),signal features(electrocardiogram features as signals),and temporal features.Since the signal of the electrical activity of the heartbeat is very sensitive to differences between high and low heartbeats,it is possible to detect some of the irregularities in the early stages of arrhythmia.This paper describes the training of supervised learning using features obtained from electrocardiogram(ECG)image to correct the limitations of arrhythmia prediction by using demographic and electrocardio-graphic signal features.An experimental study demonstrates the usefulness of the proposed Arrhythmia Prediction by Supervised Learning(APSL)method,whose features are obtained from the image formats of the electrocardiograms used as input.
文摘Olfactory ensheathing cells(OECs) transplanted into the damaged spinal cord may be considered as a valuable remedy explorations for spinal cord repair. The proliferation of transplanted olfactory ensheathing cells depends on various environmental factors and effective cues, which may include electrical fields(EFs). In this study, we investigated the proliferative capacity, morphologic alterations of olfactory ensheathing cells derived from neonate rat that occurd when exposed to two EFs of 20 Hz, 50 mV and20 Hz, 100 mV for 6 h. For both EF treatments, the MTT results revealed that the cellular proliferation of exposed group during the last 6 h of the experiment was statistically higher than that of control group. Then, we investigated morphological structure changes in the cells stained by Coomassie brilliant blue. Compared with control group, most of cells were present at intensively proliferating appearance including the microfilaments were long and thick and the accumulated appearance of cells. It is conceivable that electrical fields as a new approach may promote the growth and proliferation of OECs and may be engineered to control the survival of transplanted OECs in injured spinal cord.Although our results have been suggesting that EFs may be non-chemical strategies for cell proliferation, the fundamental mechanisms remain to be elucidated.
基金This research was supported by the National Natural Science Foundation of China(61963012,61961014)the Natural Science Foundation of Hainan Province,China(619QN195,618QN218)+1 种基金the Key R&D Project of Hainan Province,China(ZDYF2018015)Collaborative Innovation Fund Project of Tianjin University-Hainan University(HDTDU201907).
文摘The morphological features of fish,such as the body length,the body width,the caudal peduncle length,the caudal peduncle width,the pupil diameter,and the eye diameter are very important indicators in smart mariculture.Therefore,the accurate measurement of the morphological features is of great significance.However,the existing measurement methods mainly rely on manual measurement,which is operationally complex,low efficiency,and high subjectivity.To address these issues,this paper proposes a scheme for segmenting fish image and measuring fish morphological features indicators based on Mask R-CNN.Firstly,the fish body images are acquired by a home-made image acquisition device.Then,the fish images are preprocessed and labeled,and fed into the Mask R-CNN for training.Finally,the trained model is used to segment fish image,thus the morphological features indicators of the fish can be obtained.The experimental results demonstrate that the proposed scheme can segment the fish body in pure and complex backgrounds with remarkable performance.In pure background,the average relative errors(AREs)of all indicators measured all are less than 2.8%,and the AREs of body length and body width are less than 0.8%.In complex background,the AREs of all indicators are less than 3%,and the AREs of body length and body width is less than 1.8%.2020 China Agricultural University.Production and hosting by Elsevier B.V.on behalf of KeAi.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).1.Introduction With the advancing of its scientific and technological capabilities,China has made great achievements in the mariculture.The production accounts for more than 70%of the world’s overall mariculture output[1].The measurement of body length,body width and other morphological features of fish have wide application prospects in smart mariculture.Due to the difference in the quality and feeding ability of the Juvenile fish,the growth of the fish in the same pond is significantly different after a period of growth.Then,the fish needs to be classified.Grading can make fish grow better and improve feed utilization[2].The fish body length and body width are closely related to the weight of the fish.In the mariculture,the fishermen judge the growth of the fish by collecting the morphological feature of the fish,and use the information as an important reference for feeding,fishing and classification[3].At present,most of the measurement methods of fish body morphological features are manual,the operator usesmeasuring ruler to measure manually.It requires high technical level,and has high labor intensity and low efficiency.Furthermore,https://doi.
文摘Members of the Goliathus group in the order Coleoptera, family Scarabaeidae and the sub-family Cetoniidae is one among essential ecological insects worldwide with scanty documentation in Tanzania. The country was among the first point of collection of the specimen by Moser (1909) but subsequent attempts to locate and collect the specimen were unsuccessful possibly due to changed habitat and behaviour of Goliathus. Much of published work about the insect are based on the morphological characteristics of collected specimen which led to designation of six major species namely;Goliathus goliatus, G. cacicus, G. regius, G. albosignatus, G. orientalis and G. usambarensis, the last two being considered to exist in Tanzania. The current study reports on successful identification of habitats using biological cues and subsequently collected several Goliathus specimen that had been difficult to trace for more than a century. New insights into correct identity of the species by using a combination of morphological and molecular techniques have been set. The study has resolved that only one species, Goliathus orientalis with five sub-species exist in Tanzania.
基金Supported by Innovation Project of Graduate Education of Jiangsu Province(CXZZ11_0538)Project of Nanjing Construction Committee and the Administration Bureau of Dr.Sun Yat-sen's Mausoleum(200409)
文摘Apriona germari larvae were obtained via sample collection in woodland and indoor rearing. In this study, larval instars were divided by Dyar's law, and the results showed that the larval stage of A. germari comprised six instars, while the width of head capsule was the best instar-dividing structure. On the basis of instar division, tubercle numbers on the transverse furrow downside of first abdominal dorsal ambulatory ampullae, seta numbers of abdominal telson and lateral seta numbers of mandible were observed and statistically calculated. The accuracy of instar-dividing was verified by comparing with the Dyar's law. The coincidence rate of two instar-dividing results was 90. 47%. It is approved that the above morphological features could be used in instar division ofA. germari larvae.
基金supported by the National Natural Science Foundation of China(grant No.41571388)
文摘A lunar geologic map at a scale of 1:5000000 was finished in the 1970s by the National Aeronautics and Space Administration, U.S U.S. Geological Survey. Department of the Interior, Till now, the landform classification system and lunar morphologic mapping have not been clarified. The work aims to put forward a new landform classification system and to obtain index and map in the Sheet H010. Some key morphologic features of lunar surface were compared with those of the Earth. This research is very important for whole lunar morphologic mapping and unraveling evolutionary progress.
文摘Objective To develop a computer-aided diagnosis(CAD)system with automatic contouring and morphologic and textural analysis to aid on the classification of breast nodules on ultrasound images.Methods A modified Level Set method was proposed to automatically segment the breast nodules(46malignant and 60benign nodules).Following,16morphologic features and 17texture features from the extracted contour were calculated and principal component analysis(PCA)was applied to find the optimal feature vector dimensions.Fuzzy C-means classifier was utilized to identify the breast nodule as benign or malignant with selected principal vectors.Results The performance of morphologic features was 78.30%for accuracy,67.39%for sensitivity and 86.67%for specificity,while the latter was 72.64%,58.70%and 83.33%,respectively.After the combination of the two features,the result was exactly the same with the morphologic performance.Conclusion This system performs well in classifying the malignant breast nodule from the benign breast nodule.
文摘Using the method of mathematical morphology,this paper fulfills filtration,segmentation and extraction of morphological features of the satellite cloud image.It also gives out the relative algorithms,which is realized by parallel C programming based on Transputer networks.It has been successfully used to process the typhoon and the low tornado cloud image.And it will be used in weather forecast.
基金Supported by National Natural Science Foundation of China(No.61675124No.81501559)+1 种基金Natural Science Foundation of the Higher Education Institutions of Jiangsu Province,China(No.15KJB310015)Science and Technology Foundation of Nantong Technology Bureau(No.MS12015180)
文摘AIM: To predict the visual outcome in patients undergoing macular hole surgery by two novel three-dimensional morphological parameters on optical coherence tomography (OCT): area ratio factor (ARF) and volume ratio factor (VRF). METHODS: A clinical case series was conducted, including 54 eyes of 54 patients with an idiopathic macular hole (IMH). Each patient had an OCT examination before and after surgery. Morphological parameters of the macular hole, such as minimum diameter, base diameter, and height were measured. Then, the macular hole index (Mill), tractional hole index (THI), and hole form factor (HFF) were calculated. Meanwhile, novel postoperative macular hole (MH) factors, ARF and VRF were calculated by three-dimensional morphology. Bivariate correlations were performed to acquire asymptotic significance values between the steady best corrected visual acuity (BCVA) after surgery and 2D/3D arguments of MH by the Pearson method with two-tailed test. All significant factors were analyzed by the receiver operating characteristic (ROC) curve analysis of SPSS software which were responsible for vision recovery. ROC curves analyses were performed to further discuss the different parameters on the prediction of visual outcome. RESULTS: The mean and standard deviation values of patients' age, symptoms duration, and follow-up time were 64.8+8.9y (range: 28-81), 18.6+11.5d (range: 2-60), and 11.4+0.4mo (range: 6-24), respectively. Steady-post-BCVA analyzed with bivariate correlations was found to be significantly correlated with base diameter (r'0.521, P〈0.001), minimum diameter (r=0.514, P〈0.001), MHI (r -0.531, P〈0.001), THI (r=-0.386, P=-0.004), HFF (r=-0.508, P〈0.001), and ARF (r=-0.532, P〈0.001). Other characteristic parameters such as age, duration of surgery, height, diameter hole index, and VRF were not statistically significant with steady-post-BCVA. According to area under the curve (AUC) values, values of ARF, MHI, HFF, minimum diameter, THI, and base diameter are 0.806, 0.772, 0.750, 0.705, 0.690, and 0.686, respectively. However, Steady-post-BCVA analysis with bivariate correlations for VRF was no statistical significance. Results of ROC curve analysis indicated that the MHI value, HFF, and ARF was greater than 0.427, 1.027 and 1.558 respectively which could correlate with better visual acuity. CONCLUSION: Compared with MHI and HFF, ARF could effectively express three-dimensional characteristics of macular hole and achieve better sensitivity and specificity. Thus, ARF could be the most effective parameter to predict the visual outcome in macular hole surgery.
基金This work was partially supported by the Research Groups Program(Research Group Number RG-1439-033),under the Deanship of Scientific Research,King Saud University,Riyadh,Saudi Arabia.
文摘Automated grading of colon biopsy images across all magnifications is challenging because of tailored segmentation and dependent features on each magnification.This work presents a novel approach of robust magnification-independent colon cancer grading framework to distinguish colon biopsy images into four classes:normal,well,moderate,and poor.The contribution of this research is to develop a magnification invariant hybrid feature set comprising cartoon feature,Gabor wavelet,wavelet moments,HSV histogram,color auto-correlogram,color moments,and morphological features that can be used to characterize different grades.Besides,the classifier is modeled as a multiclass structure with six binary class Bayesian optimized random forest(BO-RF)classifiers.This study uses four datasets(two collected from Indian hospitals—Ishita Pathology Center(IPC)of 4X,10X,and 40X and Aster Medcity(AMC)of 10X,20X,and 40X—two benchmark datasets—gland segmentation(GlaS)of 20X and IMEDIATREAT of 10X)comprising multiple microscope magnifications.Experimental results demonstrate that the proposed method outperforms the other methods used for colon cancer grading in terms of accuracy(97.25%-IPC,94.40%-AMC,97.58%-GlaS,99.16%-Imediatreat),sensitivity(0.9725-IPC,0.9440-AMC,0.9807-GlaS,0.9923-Imediatreat),specificity(0.9908-IPC,0.9813-AMC,0.9907-GlaS,0.9971-Imediatreat)and F-score(0.9725-IPC,0.9441-AMC,0.9780-GlaS,0.9923-Imediatreat).The generalizability of the model to any magnified input image is validated by training in one dataset and testing in another dataset,highlighting strong concordance in multiclass classification and evidencing its effective use in the first level of automatic biopsy grading and second opinion.
基金Projects(60634020,60874069) supported by the National Natural Science Foundation of ChinaProject(2009AA04Z137) supported by the National High-Tech Research and Development Program of China
文摘In order to extract froth morphological feature,a bubble image adaptive segmentation method was proposed.Considering the image's low contrast and weak froth edges,froth image was coarsely segmented by using fuzzy c means(FCM) algorithm. Through the attributes of size and shape pattern spectrum,the optimal morphological structuring element was determined.According to the optimal parameters,some image noises were removed with an improved area opening and closing by reconstruction operation,which consist of image regional markers,and the bubbles were finely separated from each other by watershed transform.The experimental results show that the structural element can be determined adaptively by shape and size pattern spectrum,and the froth image is segmented accurately.Compared with other froth image segmentation method,the proposed method achieves much high accuracy,based on which,the bubble size and shape features are extracted effectively.
文摘There is increasing evidence shows that programmed cell death (PCD) can occur underphysiological, pathological or stress conditions in plants. The present review describes themorphological and biochemical characteristics, physiological functions, and the research significance ofplant PCD in detail as well as makes comparison betWeen these aspects with those in animals. Inaddition, this paper is also making exploration of the possible pathway for signal transduction, geneticregulation of plant PCD, origin and evolution of PCD and proposes a tactic for research on plant PCDalthough it is still in a preliminary stage.Compared to PCD in animals, PCD in plants under various conditions has revealed much greaterdifference in morphological and biochemical characteristics, which presents different essence far fromthe definition of apoptosis of animals. Nevertheless, no inflammation, specific fragmentation of DNAand rise of the activities of endonuclease and protease in plant PCD are still typical hallmarks fordistinguishing PCD from necrosis. On view of molecular level, as in animals, PCD in plants is alsoregulated by specific genes and involves signal transduction pathway with the involvement of a varietyof signal molecules.The physiological functions of plant PCD are similar to those in animals too. In the importantphysiological and pathological processes in plants, i.e., during reproduction, development, growth,senescenced disease-resistance, and stress-resistance against adverse circumstance conditions, PCDtakes on functions as important as proliferation throughout the whole life cycle of living organisms.Obviously, the research on PCD in plants is of vital importance that should not be ignored either intheory or in agricultural production.At present, the research on PCD in plants is focusing on collecting morphological and biochemicalevidences. But many molecules of initiation signal participating in plant PCD have been identified andseveral genes directly related to this process were isolated, which provide useful enlightenment forillustrating signal transduction pathway of PCD. Moreover, some conserved signal molecules andregulating genes were found in plant PCD, and caspase-like proteases have been detected in HR celldeath as well as in development-associated PCD. These data provide strong evidence at molecular levelfor conservation and the origin and evolution of PCD.1 The authors want to extend the sincerely thanks to Prof. Michele C. Heath (University of Toronto, Canada),Prof. Niroo Fukuda (University of Tokyo, Japan), Prof. Duran L. Nooden (University of Michigan, USA),Prof. Chris Lamb (Salk institute, California), Prof. Sarah Hake (Agricultural Research Service, USA), Prof.David L. Vaux (The Walter and Eliza Hall insititue of Medical Research, Post Office Royal MelbourneHospital, Australia), Associate Prof. Jeffrey L. Dangl (University of North Carolina, USA), Associate Prof.Eric Lain (The State University of New Jersey, USA), Dr. Maki Katsuhara (Okayama University, Japan),Prof. Sarah Hake (AgricultUral Research Service, USA), Dr. Peter P. Repetti (University of California,USA), Da Blazena Koukalova (Academy of Sciences of the Czech Republic, CZ), Dr. Iona Weir(Horticulture and Food Research Institute of New Zealand, New Zealand), Dr. Thorsten Jabs (Institute forBiology III, Germany), Dr. Hong Wang (University of California, USA) and Dr. Patrick Gallois (Universityof Perpignan, France) for their kind providing their personal latest data of their research concerned andoffering academic exchanges with us.This project is granted by the National Natural Science Foundation of China (No. 39870423) and by StateCommission of Education, Doctorate Spot Foundation.Author for correspondence. E-mail: ycsong@whu.edu.cn.Evidences in various aspects indicate that PCD origins from prokaryote, and various forms of PCD arefound along the phylogenic tree.Conclusion: A variety of endogenous and exogenous signals can break the homeostasis within plantbody and result in differentiation, proliferation, quiescence, or death of cell at length
基金National Natural Science Foundation of China,No.40871020Guangdong Natural Science Foundation, No.7005836
文摘The goal of this study is to provide information on the process of pothole growth on a gorge streambed.Pothole geometries were measured in a reach of the Dabu river bed at the head of a gorge more than 200 m deeply incising into a 650-750 m high planation surface formed in the middle Miocene in northern Guangdong,China.Geometric and derivative data of the potholes obtained from fieldwork were interpreted using standard statistical methodologies.Our study shows that the formation and development of a stream pothole were only related to local conditions of a stream reach where the pothole occurs;the weaknesses,which are usually intersect fractures,typically interconnected vertical joints,or triangular pits generated by hitting of rock fragments during floods,initiate the pothole development on a streambed;the geometrical dimensions of the potholes are controlled by tectonic joints developed in bedrock of the stream reach;the radius and the depth of potholes are strongly(log) positive correlated;the pothole shapes and the flow patterns are inconstant during pothole growth;a pothole can be formed within a short period,but cannot be fully developed and maintained for a long time in a strong incision streambed.The finding in our study can improve the understanding of Quaternary environment in Guangdong.
文摘BACKGROUND Magnetic resonance imaging(MRI)is currently the standard investigation for suspected perianal diseases.Carcinoma arising from anal fistula is very rare,and early diagnosis is often difficult.AIM To describe and summarize the MRI findings of carcinoma arising from anal fistula.METHODS In this retrospective study,records of ten patients diagnosed with carcinoma arising from anal fistula and confirmed by surgery(n=7)or biopsy(n=3)between June 2006 and August 2018 were analyzed.All patients underwent preoperative pelvic MRI.Morphologic features,signal characteristics,fistula between the mass and the anus,contrast enhancement of mass,signal and enhancement of peritumoral areas,and regional lymphadenopathy were assessed.RESULTS All ten tumors were solitary(8 mucinous adenocarcinomas and 2 adenocarcinomas).The maximum diameter of the tumors ranged from 3.4 cm to 12.4 cm(median:4.15 cm;mean:5.68 cm).Eight patients had a fistula between the mass and the anus.Contrast enhancement of the peritumoral areas was noted in three(3/5)patients.Perirectal or inguinal lymphadenopathy was noted in seven patients.Most lesions of mucinous adenocarcinoma were multiloculated and cauliflower-like,with a thin capsule and focally unclear boundary.They were markedly hyperintense on fat-suppressed T2WI,slightly hyperintense with focal hyperintensity on diffusion-weighted imaging(DWI),and hyperintense with focal hypointensity on apparent diffusion coefficient(ADC)map,with progressive mesh-like contrast enhancement.Adenocarcinomas had an infiltrative margin without a capsule and appeared heterogeneously hyperintense or slightly hyperintense on fat-suppressed T2WI,hyperintense on DWI,and hypointense on ADC map,with persistent heterogeneous enhancement.CONCLUSION Our study highlighted several characteristic and potentially helpful MRI findings to diagnose carcinomas arising from anal fistula.
基金supported by the National Key Basic Research Development Program of China (2009BAC54B01-1)National Natural Science Foundation of China (41071009 and 40701171)
文摘The dynamical processes of a typical linear dune including morphological features, dune ridge swing range and crest height were investigated at different monitoring periods in the hinterland of Tengger Desert. The results indicated that the development of linear dune depends on not only the northwesterly prevailing wind, but also the winds from northeast and southwest. The dune ridge swayed along its fundamental strike and took on an eastward movement gradually. The original dune strike was NW70° on August 3, 1994, and then changed to NE15° on April 21, 2001. The dune crest increased by 1.8 m longitudinally, which manifested strong wind-blown sand activities in this region. Wind erosion frequently occured at the bottom of sand dune, while sand accumulation appeared on its mid-upper section. The mean wind erosion depth was 25 cm on the bottom of linear dune and the height difference of the control points on the dune’s ridge was 1.13 m. Although the linear dune swayed laterally, the horizontal displacement of its ridge moved eastward 5.8 m averagely. The swing range of the dune crest line is very distinct, with a maximum value of 13.2 m. The highest site on the K-profile swayed on both sides of the dune ridge and the heights were 19.88 m at the control point K5, 19.61 m at K6 and 19.05 m at K7, respectively. The results indicated that the lateral swing of the linear dune was distinct under the northwesterly wind and it moved toward east gradually.
基金Supported by the Natural Science Foundation of Fujian Province(No.D0 2 10 0 12 )
文摘In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crystals, dendritic growth, secondary nucleation, etc. Those phenomena possibly resulted from two factors: (1) partial temperature gradient, which is caused by heat asymmetry in the electrical resistance furnace, when crystals crystalize from silicate melt; (2) constitutional supercooling near the surface of crystals. The disparity of disequilibrated crystallization phenomena in different main crystalline phases causes various morphological features of the crystal aggregates. At the same time, disequilibrated crystallization causes great stress retained in the crystals, which results in cracks in glazes when the temperature drops. According to the results, the authors analyzed those phenomena and displayed correlative figures and data.
基金supported by the Science and Technology Project of Guangdong Province (No.2009B060700124)the Science and Technology Project of Guangzhou Municipality,Guangdong Province,China (No.2010Y1-C801)
文摘Baseline wander is a common noise in electrocardiogram (ECG) results.To effectively correct the baseline and to preserve more underlying components of an ECG signal,we propose a simple and novel filtering method based on a statistical weighted moving average filter.Supposed a and b are theminimum and maximum of all sample values within a moving window,respectively.First,the whole region [a,b] is divided into M equal sub-regions without overlap.Second,three sub-regions with the largest sample distribution probabilities are chosen (except M<3) and incorporated into one region,denoted as [a 0,b 0 ] for simplicity.Third,for every sample point in the moving window,its weight is set to 1 if its value falls in [a 0,b 0 ];otherwise,its weight is 0.Last,all sample points with weight 1 are averaged to estimate the baseline.The algorithm was tested by simulated ECG signal and real ECG signal from www.physionet.org.The results showed that the proposed filter could more effectively extract baseline wander from ECG signal and affect the morphological feature of ECG signal considerably less than both the traditional moving average filter and wavelet package translation did.