Regional gray matter abnormality in hepatic myelopathy patients after transjugular intrahepatic portosystemic shunt: a voxel-based morphometry study

Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain motor control center in hepatic myelopathy is unknown. This study aimed to investigate the gray matter changes in patients with hepatic myelopathy secondary to transjugular intrahepatic portosystemic shunt and to examine their clinical relevance. This was a cross-sectional study. Twenty-three liver failure patients with hepatic myelopathy(hepatic myelopathy group), 23 liver failure patients without hepatic myelopathy(non-hepatic myelopathy group) after transjugular intrahepatic portosystemic shunt, and 23 demographically matched healthy volunteers were enrolled from March 2014 to November 2016 at Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China. High-resolution magnetization-prepared rapid gradient-echo brain imaging was acquired. Group differences in regional gray matter were assessed using voxel-based morphometry analysis. The relationship between aberrant gray matter and motor characteristics was investigated. Results demonstrated that compared with the non-hepatic myelopathy group, gray matter volume abnormalities were asymmetric, with decreased volume in the left insula(P = 0.003), left thalamus(P = 0.029), left superior frontal gyrus(P = 0.006), and right middle cingulate cortex(P = 0.021), and increased volume in the right caudate nucleus(P = 0.017), corrected with open-source software. The volume of the right caudate nucleus in the hepatic myelopathy group negatively correlated with the lower limb clinical rating of the Fugl-Meyer Assessment(r = –0.53, P = 0.01). Compared with healthy controls, patients with and without hepatic myelopathy exhibited overall increased gray matter volume in both thalami, and decreased gray matter volume in both putamen, as well as in the globus pallidus, cerebellum, and vermis. The gray matter abnormalities we found predominantly involved motor-related regions, and may be associated with motor dysfunction. An enlarged right caudate nucleus might help to predict weak lower limb motor performance in patients with preclinical hepatic myelopathy after transjugular intrahepatic portosystemic shunt. This study was approved by the Ethics Committee of Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China(approval No. 20140227-6) on February 27, 2014.

Regional brain structural abnormality in ischemic stroke patients:a voxel-based morphometry study

Our previous study used regional homogeneity analysis and found that activity in some brain areas of patients with ischemic stroke changed significantly. In the current study, we examined structural changes in these brain regions by taking structural magnetic resonance imaging scans of 11 ischemic stroke patients and 15 healthy participants, and analyzing the data using voxel-based morphometry. Compared with healthy participants, patients exhibited higher gray matter density in the left inferior occipital gyrus and right anterior white matter tract. In contrast, gray matter density in the right cerebellum, left precentral gyrus, right middle frontal gyrus, and left middle temporal gyrus was less in ischemic stroke patients. The changes of gray matter density in the middle frontal gyrus were negatively associated with the clin- ical rating scales of the Fugl-Meyer Motor Assessment （r = -0.609, P = 0.047） and the left middle temporal gyrus was negatively correlated with the clinical rating scales of the nervous functional deficiency scale （r = -0.737, P = 0.010）. Our findings call objectively identify the functional abnormality in some brain regions of ischemic stroke patients.

Brain structure in post-traumatic stress disorder A voxel-based morphometry analysis

This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, using the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter volume was the highest in the trauma control group, followed by the symptoms-improved group, and the lowest in the chronic post-traumatic stress disorder group. Compared with the symptoms-improved group, the gray matter volume in the lingual gyrus of the right occipital lobe was reduced in the chronic post-traumatic stress disorder group. Compared with the trauma control group, the gray matter volume in the right middle occipital gyrus and left middle frontal gyrus was reduced in the symptoms-improved group. Compared with the trauma control group, the gray matter volume in the left superior parietal lo- bule and right superior frontal gyrus was reduced in the chronic post-traumatic stress disorder group. The gray matter volume in the left superior parietal Iobule was significantly positively correlated with the State-Trait Anxiety Inventory subscale score in the symptoms-improved group and chronic post-traumatic stress disorder group （r = 0.477, P = 0.039）. Our findings indicate that （1） chronic post-traumatic stress disorder patients have gray matter structural damage in the prefrontal lobe, oc- cipital lobe, and parietal lobe, （2） after post-traumatic stress, the disorder symptoms are improved and gray matter structural damage is reduced, but cannot recover to the trauma-control level, and （3） the superior parietal Iobule is possibly associated with chronic post-traumatic stress disorder. Post-traumatic stress disorder patients exhibit gray matter abnormalities.

White matter abnormalities in young males with antisocial personality disorder Evidence from voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis

Voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis was used to investigate the structural characteristics of white matter in young males with antisocial personality disorder （APD） and healthy controls without APD. The results revealed that APD subjects, relative to healthy subjects, exhibited increased white matter volume in the bilateral prefrontal lobe, right insula, precentral gyrus, bilateral superior temporal gyrus, right postcentral gyrus, right inferior parietal Iobule, right precuneus, right middle occipital lobe, right parahippocampal gyrus and bilateral cingulate, and decreased volume in the middle temporal cortex and right cerebellum. The white matter volume in the medial frontal gyrus was significantly correlated with antisocial type scores on the Personality Diagnostic Questionnaire in APD subjects. These experimental findings indicate that white matter abnormalities in several brain areas may contribute to antisocial behaviors in APD subjects.

Differences in brain structure in patients with distinct sites of chronic pain:A voxel-based morphometric analysis

A reduction in gray matter volume is common in patients with chronic back pain, and different types of pain are associated with gray matter abnormalities in distinct brain regions. To examine differ- ences in brain morphology in patients with low back pain or neck and upper back pain, we investi- gated changes in gray matter volume in chronic back pain patients having different sites of pain using voxel-based morphometry. A reduction in cortical gray matter volume was found primarily in the left postcentral gyrus and in the left precuneus and bilateral cuneal cortex of patients with low back pain. In these patients, there was an increase in subcortical gray matter volume in the bilateral putamen and accumbens, right pallidum, right caudate nucleus, and left amygdala. In upper back pain patients, reduced cortical gray matter volume was found in the left precentral and left postcen- tral cortices. Our findings suggest that regional gray matter volume abnormalities in low back pain patients are more extensive than in upper back pain patients. Subcortical gray matter volume in- creases are found only in patients with low back pain.

Magnetic resonance morphometry of the loss of gray matter volume in Parkinson's disease patients

Voxel-based morphometry can be used to quantitatively compare structural differences and func-tional changes of gray matter in subjects. In the present study, we compared gray matter images of 32 patients with Parkinson’s disease and 25 healthy controls using voxel-based morphometry based on 3.0 T high-field magnetic resonance T1-weighted imaging and clinical neurological scale scores. Results showed that the scores in Mini-Mental State Examination and Montreal Cognitive Assessment were lower in patients compared with controls. In particular, the scores of visuospatial/executive function items in Montreal Cognitive Assessment were significantly reduced, but mean scores of non-motor symptoms significantly increased, in patients with Parkinson’s dis-ease. In addition, gray matter volume was significantly diminished in Parkinson’s disease patients compared with normal controls, including bilateral temporal lobe, bilateral occipital lobe, bilateral parietal lobe, bilateral frontal lobe, bilateral insular lobe, bilateral parahippocampal gyrus, bilateral amygdale, right uncus, and right posterior lobe of the cerebel um. These findings indicate that voxel-based morphometry can accurately and quantitatively assess the loss of gray matter volume in patients with Parkinson＇s disease, and provide essential neuroimaging evidence for multisystem pathological mechanisms involved in Parkinson’s disease.

Assessing gray matter volume in patients with idiopathic rapid eye movement sleep behavior disorder

Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital(approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry(ISRCTN18238599).

Application of voxel-based morphometric method to detect brain changes in children with non-cyanotic congenital heart disease

BACKGROUND Congenital heart disease(CHD)is a cardiovascular malformation caused by abnormal heart and/or vascular development in the fetus.In children with CHD,abnormalities in the development and function of the nervous system are common.At present,there is a lack of research on the preoperative neurological development and injury in young children with non-cyanotic CHD.AIM To determine the changes in white matter,gray matter,and cerebrospinal fluid(CSF)by magnetic resonance imaging(MRI)in children with non-cyanotic CHD as compared with healthy controls.METHODS Children diagnosed with non-cyanotic CHD on ultrasonography(n=54)and healthy control subjects(n=35)were included in the study.All the subjects were aged 1-3 years.Brain MRI was performed prior to surgery for CHD.The SPM v12 software was used to calculate the volumes of the gray matter,white matter,CSF,and the whole brain(sum of the gray matter,white matter,and CSF volumes).Volume differences between the two groups were analyzed.Voxel-based morphometry was used to compare specific brain regions with statistically significant atrophy.RESULTS Compared with the control group,the study group had significantly reduced whole-brain white matter volume(P<0.05),but similar whole-brain gray matter,CSF,and whole-brain volumes(P>0.05).As compared with the healthy controls,children with non-cyanotic CHD had mild underdevelopment in the white matter of the anterior central gyrus,the posterior central gyrus,and the pulvinar.CONCLUSION Children with non-cyanotic CHD show decreased white matter volume before surgery,and this volume reduction is mainly concentrated in the somatosensory and somatic motor nerve regions.

Voxel-Based Morphometric Study on Chinese Blind Men's Brain Structure

Many studies have shown the functional relevance of cross-modal plasticity in blind men. In order to study the changes of their brain structure, voxel-based morphometry （VBM） methods are used. The regional gray matter （GM） and white matter （WM） concentrations of magnetic resonance （MR） images from 11 blind people and 9 sighted control subjects are compared using standard VBM. Optimized VBM is also discussed to measure the absolute local volume of GM or WM. Consistent results are achieved by statistical analysis with these methods. There are distinct differences not only in visual cortex but also the sensory area, auditory area and motor area. GM concentrations in blind men significantly decreased in Brodmann 7 and 22. While in Brodmann 18 and 19, GM concentration increased. GM volumes decreased in Brodmann 3, 4, 6, 9 and 45. On the other hand, both WM concentration and volume increased in Brodmann 7. These results suggest that early visual deprivation can lead to changes in the brain structural anatomy which is consistent with the cortical cross-modal reorganization found by functional imaging. It may help to discover the relationship between the brain structural anatomy and the brain functional data of blind men at a macroscopic level from neuroimaging perspective.

Abnormal volumetric brain morphometry and cerebral blood flow in adolescents with depression

BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural alterations.However,preliminary studies have documented the pathophysiological changes in certain brain regions,such as the cerebellum,highlighting a need for further research to support the current understanding of this disease.AIM To study brain changes in depressed adolescents.METHODS This study enrolled 34 adolescents with depression and 34 age-,sex-,and education-level-matched healthy control(HC)individuals.Structural and functional alterations were identified when comparing the brains of these two participant groups through voxel-based morphometry and cerebral blood flow(CBF)analysis,respectively.Associations between identified brain alterations and the severity of depressive symptoms were explored through Pearson correlation analyses.RESULTS The cerebellum,superior frontal gyrus,cingulate gyrus,pallidum,middle frontal gyrus,angular gyrus,thalamus,precentral gyrus,inferior temporal gyrus,superior temporal gyrus,inferior frontal gyrus,and supplementary motor areas of adolescents with depression showed an increase in brain volume compared to HC individuals.These patients with depression further presented with a pronounced drop in CBF in the left pallidum(group=98,and peak t=-4.4324),together with increased CBF in the right percental gyrus(PerCG)(group=90,and peak t=4.5382).In addition,17-item Hamilton Depression Rating Scale scores were significantly correlated with the increased volume in the opercular portion of the left inferior frontal gyrus(r=-0.5231,P<0.01).CONCLUSION The right PerCG showed structural and CBF changes,indicating that research on this part of the brain could offer insight into the pathophysiological causes of impaired cognition.

Morphometric Analysis of Drainage Basins in the Western Arabian Peninsula Using Multivariate Statistics

The uplift of the Arabian Shield and the opening of the Red Sea led to the development of steep drainage systems in the Western Arabian Peninsula. Although the Peninsula has been studied from a geological perspective, in relation to oil production, plate tectonics and eolian systems such as sand dunes, the steep mountainous drainage basins have received much less attention. This paper aims to assess the characteristics and development of 36 drainage basins in the Western Arabian Peninsula, using a digital elevation model (DEM), principal component analysis (PCA), and hierarchical cluster analysis (CA). Three major principal components (PC1 to PC3) are found to explain 73% of total variance. CA divided the basins into two or four groups. The division by CA strongly reflects PC1, showing that the two analyses give comparable results. PC1 strongly reflects basin dimensions and drainage texture, and their positive correlations indicate the significant effect of basin relief and slope on mass wasting and limited stream incision in small basins under an arid climate. PC2 mainly reflects the effect of bedrock geology, suggesting that volcanic rocks tend to produce more elongated and less eroded immature basins than crystalline rocks do. PC3 mainly reflects the basin relief and slope and the length of each stream segment, which may also reflect the effect of mass wasting on stream development.

Volume Gain of Brainstem on Medication-Overuse Headache Using Voxel-Based Morphometry

Background： Histopathology identified the anatomical and molecular abnormalities ofbrainstem nuclei in migraine patients. However, the exact whole brainstem structural changes in vivo have not yet been identified in medication-overuse headache （MOH） transformed from migraine. The aim of this study was to investigate the regional volume changes over the whole brainstem in the MOH patients using voxel-based morphometry （VBM） in vivo.Methods： High-resolution three-dimensional structural images were obtained using a 3.0-Tesla magnetic resonance system from 36 MOH patients and 32 normal controls （NCs） who were consecutively recruited from the International Headache Center, Chinese People＇s Liberation Army General Hospital, from March 2013 to June 2016. VBM was used to assess the brainstem structural alteration in the MOH patients, and voxel-wise correlation was performed to evaluate the relationship with the clinical characteristics.Results： The brainstem region with increased volume located in the left ventrolateral periaqueductal gray （MNI coordinate： -1, -33, -8）, ventral tegmental area （MNI coordinate： 0, -22, - 12）, bilateral substantia nigra （MNI coordinate： -8, - 16, - 12, 9, - 16, - 12）, and trigeminal root entry zone （MNI coordinate： -19, -29, -31; 19, -32, -29） in MOH patients compared with NCs. The headache visual analog scale score was positively related with the left rostral ventromedial medulla （RVM） （MNI coordinate： -1, -37, -56; cluster size： 20; r = 0.602） in the MOH patients.Conclusions： The regional volume gain ofbrainstem could underlie the neuromechanism of impaired ascending and descending pathway in the MOH patients, and the left RVM volume alteration could imply the impaired tolerance ofnociceptive pain input and could be used to assess the headache disability in the MOH patients.

Effect of layer thickness and voxel size inversion on leaf area density based on the voxel-based canopy profiling method

Voxel-based canopy profiling is commonly used to determine small-scale leaf area.Layer thickness and voxel size impact accuracy when using this method.Here,we determined the optimal combination of layer thickness and voxel size to estimate leaf area density accurately.Terrestrial LiDAR Stonex X300 was used to generate point cloud data for Masson pines(Pinus massoniana).The canopy layer was stratified into 0.10-1.00-m-thick layers,while voxel size was 0.01-0.10 m.The leaf area density of individual trees was estimated using leaf area indices for the upper,middle,and lower canopy and the overall canopy.The true leaf area index,obtained by layered harvesting,was used to verify the inversion results.Leaf area density was inverted by nine combinations of layer thickness and voxel size.The average relative accuracy and mean estimated accuracy of these combined inversion results exceeded 80%.When layer thickness was 1.00 m and voxel size 0.05 m,inversion was closest to the true value.The average relative accuracy was 92.58%,mean estimated accuracy 98.00%,and root mean square error 0.17.The combination of leaf area density and index was accurately retrieved.In conclusion,nondestructive voxel-based canopy profiling proved suitable for inverting the leaf area density of Masson pine in Hetian Town,Fujian Province.

Morphometric discrimination between females of two isomorphic sand fly species, Phlebotomus caucasicus and Phlebotomus mongolensis(Diptera:Phlebotominae) in endemic and non-endemic foci of zoonotic cutaneous leishmaniasis in Iran

Objective: To delineate reliable morphological characteristics for identifying and separating female Phlebotomus caucasicus and Phlebotomus mongolensis which exist sympatrically in the main foci of zoonotic cutaneous leishmaniasis in Iran.Methods: Sand flies were collected using sticky trap papers from active colonies of rodent burrows installed from 16 catching sites. Morphometric measurements were analyzed of 87 Phlebotomus caucasicus and 156 Phlebotomus mongolensis. Univariate and multivariate analysis were carried out to determine significant morphometric variables for discrimination of the two species. Finally, seven morphological characteristics of 65 female Phlebotomus caucasicus and 124 female Phlebotomus mongolensis were described.Results: Univariate and multivariate analyses of 10 morphometric variables via Discriminant Function Analysis(DFA) and Principal Component Analysis(PCA) showed that five morphometric variables had an accuracy of 100% for discriminating female Phlebotomus caucasicus and Phlebotomus mongolensis. Moreover, PCA revealed that the five morphometric variables with the highest loadings separated these two species. Morphological studies on antennal flagellum(and its associated structures) and mouth-parts of female specimens demonstrated significant differences in several structures.Conclusions: The results show that morphological and morphometrical features can be used to discriminate two female isomorphic species, Phlebotomus caucasicus and Phlebotomus mongolensis accurately.

Quantitative Analysis of Geomorphometric Parameters of Wadi Kerak, Jordan, Using Remote Sensing and GIS

Geomorphometric analysis was carried out to illustrate the drainage characteristics and morphology of Wadi Kerak watershed, southern Jordan. The basic and derived morphometric parameters (linear, areal and relief aspects of drainage network) for the basin were determined using ASTER DEM (30 m resolution) and Geographic Information System (GIS). These parameters describe the basin drainage network, geometry, texture, and relief characteristics. The hypsometric curve, hypsometric integral and clinographic curve were also prepared using topographic maps of 1:50,000 scale. Findings have revealed that W. Kerak is in the youth-age stage of geomorphic evolution. Fluvial erosion associated with successive phases of rejuvenation plays a significant role in drainage basin development, whereas structure and tectonics, lithology and relief dictate the drainage pattern and morphological setting of the catchment. The drainage area of the watershed is 190.9 km2 and constitutes a 5th-order drainage basin. The commonly observed drainage patterns are the trellis type, with sub-dendritic pattern recognized in the upper catchment. The drainage pattern, and the semi-linear alignment of main and branching drainage indicate the prominent influence of the Kerak-Al-fiha fault system on the drainage network. High dissection, relative relief, relief ratio, steep slopes and breaks of slopes are characteristic of W. Kerak. Morphometric analysis reveals that four rejuvenation phases caused severe erosion and down cutting activity in the past, and it is still susceptible to surface erosion at present.

Transient elastography compared to liver biopsy and morphometry for predicting fibrosis in pediatric chronic liver disease: Does etiology matter?

AIM: To evaluate transient elastography(TE) as a noninvasive tool in staging liver fibrosis compared with liver biopsy and morphometry in children with different chronic liver diseases.METHODS: A total of 90 children [50 with chronic hepatitis C virus(HCV), 20 with autoimmune hepatitis(AIH) and 20 with Wilson disease] were included in the study and underwent liver stiffness measurement(LSM) using TE. Liver biopsies were evaluated for fibrosis, qualitatively, by Ishak score and quantitatively by fibrosis area fraction(FAF) using digital image analysis(morphometry). LSM was correlated with fibrosis and other studied variables using spearman correlation. A stepwise multiple regression analysis was alsoperformed to examine independent factors associated with LSM. Different cut-off values of LSM were calculated for predicting individual fibrosis stages using receiveroperating characteristic curve. Cut-off values with optimal clinical performance(optimal sensitivity and specificity simultaneously) were selected.RESULTS: The majority of HCV group had minimal activity(80%) and no/mild fibrosis(72%). On the other hand, the majority of AIH group had mild to moderate activity(70%) and moderate to severe fibrosis(95%) and all Wilson disease group had mild to moderate activity(100%) and moderate to severe fibrosis(100%). LSM correlated significantly with both FAF and Ishak scores and the correlation appeared better with the latter(r = 0.839 vs 0.879, P < 0.0001 for both). LSM discriminated individual stages of fibrosis with high performance. Sensitivity ranged from 81.4% to 100% and specificity ranged from 75.0% to 97.2%. When we compared LSM values for the same stage of fibrosis, they varied according to the different etiologies. Higher values were in AIH(16.15 ± 7.23 k Pa) compared to Wilson disease(8.30 ± 0.84 k Pa) and HCV groups(7.43 ± 1.73 k Pa). Multiple regression analysis revealed that Ishak fibrosis stage was the only independent variable associated with higher LSM(P < 0.0001).CONCLUSION: TE appears reliable in distinguishing different stages of liver fibrosis in children. However, its values vary according to the disease type. For that, a disease-specific estimation of cut-off values for fibrosis staging is worthy.

Comparative Morphology and Morphometry of Six Biotypes of Bemisia tabaci (Hemiptera: Aleyrodidae) from China

Morphology and morphometry of six biotypes （B, Q, Cv, ZHJ-1, ZHJ-2 and ZHJ-3） of Bemisia tabaci （Gennadius） from China on cotton plants were studied by using microscopes. Nymphal body sizes and characters were measured and observed, especially on the 4th instar （pupal case）, including the vasiform orifice, operculum, lingula, length and thickness of anterior and posterior wax margins, width of thoracic tracheal combs. Adult characters of both sexes were investigated including the body size, compound eyes, antennal segments, vasiform orifice, hind tarsi and genitals. The results indicated that differences of some morphological characters or morphometrics were significant among the six biotypes of B. tabaci in China： （1） Pupal sizes of the exotic biotypes （B and Q） were significantly larger than the indigenous biotypes with the following order as B〉Q〉ZHJ-I〉Cv〉ZHJ-3〉ZHJ-2; （2） for both male and female adults, sizes of all characters investigated in the invading biotypes （B and Q）, especially B, were much larger than those of the indigenous ones.

作物农艺性状与形态结构表型智能识别技术综述

[目的/意义]作物农艺性状与形态结构表型智能识别是作物智慧育种的主要内容,是研究“基因型—环境型—表型”相互作用关系的基础,对现代作物育种具有重要意义。[进展]大规模、高通量作物表型获取设备是作物表型获取、分析、测量、识别等的基础和重要手段。本文介绍了高通量作物表型主流平台和感知成像设备的功能、性能以及应用场景。分析了作物株高获取、作物器官检测与技术等农艺性状智能识别和作物株型识别、作物形态信息测量以及作物三维重建等形态结构智能识别技术的研究进展及挑战。[结论/展望]从研制新型低成本田间智能作物表型获取与分析装备、提升作物表型获取田间环境的标准化与一致性水平、强化田间作物表型智能识别模型的通用性,研究多视角、多模态、多点连续分析与时空特征融合的作物表型识别方法,以及提高模型解释性等方面,展望了作物表型技术主要发展方向。

Lack of evidence for sufficiently isolated populations of Glossina morsitans submorsitans on the Adamawa Plateau of Cameroon following geometric morphometric analysis

Trypanosomosis remains the number one killer of livestock in spite of efforts made to eradicate tsetse flies in the Adamawa plateau of Cameroon. Acetone-baited Laveissière type biconical traps were pitched at 100 meter intervals in strategic geo-referenced positions in various ecological niches of the landscape for 5 consecutive days in selected villages in Mayo Rey, Mbere, Vina and Faro et Deo divisions. All 493 tsetse flies captured in sites other than Mboula wereG. morsitans submositans.Measurement of different morphometric characters on the wings of each individual fly was undertaken using the Du Jardin package. The data was processed and analysed by “Permutaciones, Analisis Discriminante (PAD)” and “Bootstraps, Analisis en Componentes principales”. The three major sampling sites on the plateau yielded similar results as demonstrated by the neighbour joining tree of Mahalanobis distances but tests using PAD showed the differences between group means to be significant

双相情感障碍患者脑结构及脑血流灌注的MRI研究进展

双相情感障碍(BD)是一类常见精神心理疾病,其高发病率、高致残率、高死亡率引起广泛关注。在临床实践中,BD的初次准确诊断率较低,容易被误诊为单相抑郁症。许多神经影像学研究表明,BD患者部分脑区的皮层厚度、灰质、白质以及功能活动发生改变,但其特异的神经影像学指标尚未明确,对于BD发病的特殊病理生理机制也尚未完全阐明。因此,本文梳理了近年来关于BD患者研究脑皮层结构及血流灌注的方法进行综述,以期望后期进行更深入的研究。