Energy-dispersive X-ray Spectroscopy for the Quantitative Analysis of Pyrite Thin Specimens

To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantitative analysis of pyrite materials.Additionally,the k factor of pyrite is calculated experimentally.To develop an appropriate non-standard quantitative analysis model for pyrite materials,the experimentally calculated k factor is compared with that estimated from the non-standard quantitative analytical model of the instrument software.The experimental findings demonstrate that the EDS attached to a TEM can be employed for precise quantitative analysis of micro-and nanoscale regions of pyrite materials.Furthermore,it serves as a reference for improving the results of the EDS quantitative analysis of other sulfides.

Unusual histopathological findings in appendectomy specimens from patients with suspected acute appendicitis

AIM: To investigate the prevalence and implications of unusual histopathological findings in appendectomy specimens from patients with suspected acute appendicitis. METHODS: The demographic and histopathological data of 1621 patients (≥ 16 years-old) who underwent appendectomy to treat an initial diagnosis of acute appendicitis between January 1999 and November 2011 were retrospectively assessed. Microscopic findings were used to classify the patients under six categories: appendix vermiformis, phlegmonous appendicitis, gan- grenous appendicitis, perforated appendicitis, supurative appendicitis, and unusual histopathologic findings. The demographic and clinicopathologic characteristics of patients with unusual histopathologic findings were evaluated in detail, and re-analysis of archived resected appendix specimens was carried out. RESULTS: A total of 912 males and 709 females, from16 to 94 years old, were included in the study and comprised 789 cases of suppurative appendicitis, 370 cases of appendix vermiformis, 243 cases of perforated gangrenous appendicitis, 53 cases of flegmaneous appendicitis, 32 cases of gangrenous appendicitis, and 134 (8.3%) cases of unusual histopathological findings. The unusual histopathological findings included fibrous obliteration (n = 62), enterobius vermicularis (n = 31), eosinophilic infiltration (n = 10), mucinous cystadenoma (n = 8), carcinoid tumor (n = 6), granulomatous inflammation (n = 5), adenocarcinoma (n = 4; one of them mucinous), and mucocele (n = 3), adenomatous polyp (n = 1), taenia sup (n = 1), ascaris lumbricoides (n = 1), appendiceal diverticula (n = 1), and B cell non-hodgkin lymphoma (n = 1). None of the 11 patients with subsequent diagnosis of tumor were suspected of cancer prior to the appendectomy. CONCLUSION: Even when the macroscopic appearance of appendectomy specimens is normal, histopathological assessment will allow early diagnosis of many unusual diseases.

Experimental study on the flow behaviour of water-sand mixtures in fractured rock specimens

The study of flow behaviour of water-sand mixtures in fractured rocks is of great necessity to understand the producing mechanism and prevention of water inrush and sand gushing accidents.A self-developed seepage test system is used in this paper to conduct laboratory experiments in order to study the influence of the particle size distribution,the void ratio,and the initial mass of Aeolian sand on the flow behavior.It is concluded that the water flow velocity is insensitive to the initial mass of the Aeolian sand but increases with the power exponent in the Talbot formula and the specimen height.The outflow of the Aeolian sand increases with the power exponent in the Talbot formula,the specimen height,and the initial mass of the Aeolian sand.Besides,the outflow of the Aeolian sand changes exponentially with the water flow velocity.Finally,it is found that the fractured specimen has a maximum sand filtration capacity beyond which the outflow of the Aeolian sand significantly increases with the initial mass of the Aeolian sand.

RT-nPCR Assays for Amplification and Sequencing of VP1 Genes in Human Enterovirus A–D from Clinical Specimens

Objective To develop RT-nPCR assays for amplifying partial and complete VP1 genes of human enteroviruses(HEVs)from clinical samples and to contribute to etiological surveillance of HEV-related diseases.Methods A panel of RT-nPCR assays,consisting of published combined primer pairs for VP1 genes of HEV A–C and in-house designed primers for HEV-D,was established in this study.The sensitivity of each RT-nPCR assay was evaluated with serially diluted virus stocks of five serotypes expressed as CCID50 perμL and copies perμL,and the newly established methods were tested in clinical specimens collected in recent years.Results The sensitivity of RT-nPCR assays for amplifying partial VP1 gene of HEVs was 0.1 CCID50 perμL and 10 virus copies perμL,and for the complete VP1 gene was 1 CCID50 perμL and 100 virus copies perμL,using serially-diluted virus stocks of five serotypes.As a proof-of-concept,25 serotypes were identified and complete VP1 sequences of 23 serotypes were obtained by this system among 858 clinical specimens positive for HEVs during the past eight surveillance seasons.Conclusion This RT-nPCR system is capable of amplifying the partial and complete VP1 gene of HEV A–D,providing rapid,sensitive,and reliable options for molecular typing and molecular epidemiology of HEVs in clinical specimens.

Development of a reverse-transcription loop-mediated isothermal amplification assay to detect avian influenza viruses in clinical specimens

In recent years,the avian influenza has brought not only serious economic loss to the poultry industry in China but also a serious threat to human health because of the avian influenza virus(AIV) gene recombination and reassortment.Until now,traditional RT-PCR,fluorescence RT-PCR and virus isolation identification have been developed and utilized to detect AIV,but these methods require high-level instruments and experimental conditions,not suitable for the rapid detection in field and farms.In order to develop a rapid,sensitive and practical method to detect and identify AIV subtypes,4 specific primers to the conserved region of AIV M gene were designed and a loop-mediated isothermal amplification(RT-LAMP) method was established.Using this method,the M gene of H1–H16 subtypes of AIV were amplified in 30 min with a water bath and all 16 H subtypes of AIV were able to be visually identified in presence of fluorescein,without cross reaction with other susceptible avian viruses.In addition,the detection limit of the common H1,H5,H7,and H9 AIV subtypes with the RT-LAMP method was 0.1 PFU(plaque-forming unit),which was 10 times more sensitive than that using the routine RT-PCR.Further comparative tests found that the positivity rate of RT-LAMP on detecting clinical samples was 4.18%(14/335) comparing with 3.58%(12/335) from real-time RT-PCR.All these results suggested that the RT-LAMP method can specifically detect and identify AIV with high sensitivity and can be considered as a fast,convenient and practical method for the clinic test and epidemiological investigation of AIV.

Histopathological characteristics of needle core biopsy and surgical specimens from patients with solitary hepatocellular carcinoma or intrahepatic cholangiocarcinoma

BACKGROUND Pathological manifestations of hepatic tumours are often associated with prognosis. Although surgical specimens(SS) can provide more information,currently, pre-treatment needle core biopsy(NCB) is increasingly showing important value in understanding the nature of liver tumors and even in diagnosis and treatment decisions. However, the concordance of the clinicopathological characteristics and immunohistochemical(IHC) staining between NCB and SS from patients with hepatic tumours were less concerned.AIM To introduce a more accurate method for interpreting the IHC staining results in order to improve the diagnostic value of hepatic malignancy in NCB samples.METHOD A total of 208 patients who underwent both preoperative NCB and surgical resection for hepatocellular carcinoma(HCC) or intrahepatic cholangiocarcinomaRESULTS Morphologically, the presence of compact tumour nests or a cord-like structure in NCB was considered the primary cause of misdiagnosis of HCC from ICC. The kappa statistic showed a moderate agreement in histomorphology(k = 0.504) and histological grade(k = 0.488) between NCB and SS of the tumours. A 4-tier(+++,++, +, and-) scoring scheme that emphasized the focal neoplastic cell immunoreactivity of tumour cells revealed perfect concordance of CK19, GPC3 and HepPar1 between NCB and SS(k = 0.717; k = 0.768; k = 0.633). Furthermore,with the aid of a binary classification derived from the 4-tier score, a high concordance was achieved in interpreting the IHC staining of the three markers between NCB and final SS(k = 0.931; k = 0.907; k = 0.803), increasing the accuracy of NCB diagnosis C(k = 0.987; area under the curve = 0.997, 95%CI: 0.990-1.000; P< 0.001).CONCLUSION These findings imply that reasonable interpretation of IHC results in NCB is vital for improving the accuracy of tumour diagnosis. The simplified binary classification provides an easy and applicable approach.

Machine learning-based constitutive models for cement-grouted coal specimens under shearing

Cement-based grouting has been widely used in mining engineering;its constitutive law has not been comprehensively studied.In this study,a novel constitutive law of cement-grouted coal specimens(CGCS)was developed using hybrid machine learning(ML)algorithms.Shear tests were performed on CGCS for the analysis of stress-strain curves and the preparation of the dataset.To maintain the interpretation of the trained ML models,regression tree(RT)was used as the main technique.The effect of maximum RT depth(Maxdepth)on its performance was studied,and the hyperparameters of RT were tuned using the genetic algorithm(GA).The RT performance was also compared with ensemble learning techniques.The optimum correlation coefficient on the training set was determined as 0.835,0.946,0.981,and 0.985 for RT models with Maxdepth=3,5,7,and 9,respectively.The overall correlation coefficient was over 0.9 when the Maxdepth≥5,indicating that the constitutive law of CGCS can be well described.However,the failure type of CGCS could not be captured using the trained RT models.Random forest was found to be the optimum algorithm for the constitutive modeling of CGCS,while RT with the Maxdepth=3 performed the worst.

<i>Blastomyces dermatitidis</i>Antibody Responses in Serial Serum Specimens from Dogs with Blastomycosis: Comparison of Different Yeast Lysate Antigens

The systemic fungal organism, Blastomyces dermatitidis causes blastomycosis in animals and hu-mans. This study was designed to evaluate antibody detection in 55 serial serum specimens from 9 dogs with blastomycosis using B. dermatitidis yeast lysate antigens produced from two human isolates (B5896;B5931) and two dog isolates (ERC-2;T-58) with the indirect enzyme linked im-munosorbent assay (ELISA;peroxidase system) to determine an optimal lysate antigen(s) for use in the ELISA to detect antibody in the dog serum specimens. The mean absorbance values when the lysate antigens were compared with respect to their ability to detect antibody in the day 0 sera from the 9 dogs were 1.024 (ERC-2), 1.351 (B5896), 1.700 (B5931) and 2.084 (T-58) respectively. All of the reagents exhibited a high level of sensitivity and in all instances the amount of antibody declined as the time interval post-treatment increased, but the T-58 lysate prepared from the dog isolate from Tennessee was the optimal reagent. We continue to evaluate antigens for B. derma-titidis antibody detection in different immunodiagnostic assays.

THE ANALYSES OF THE THREE-DIMENSIONAL STRESS STRUCTURE NEAR THE CRACK TIP OF MODE I CT SPECIMENS IN ELASTICPLASTIC STATE(Ⅰ)—THE ANALYSES OF CONSTRAINT PARAMETERS AND FRACTURE PARAMETERS

In the present paper,three dimensional analyses of some general constraintparameters and fracture parameters near the crack tip of Mode I CT specimens in twodifferent thicknesses are carried out by employing ADINA program.The results revealthat the constraints along the thickness direction are obviously separated into twoparts:the keeping similar high constraint field（Z1）and rapid reducing constraintsone（Z2）.The two fields are experimentally confiremed to correspond to the smoothregion and the shear lip on the fracture face respectively.So the three dimensionalstress structure of Mode I specimens can be derived through discussing the two fieldsrespectively.The distribution of the Crack Tip Opening Displacement（CTOD）alongthe thickness direction and the three dimensional distribution of the void growth ratio（V9 ）near the crack tip are also obtained.The two fracture parameters are in similartrends along the thickness direction,and both of them can reflect the effect ofthickness and that of the loading

Characterizations and Analysis of the Mold from Animal Specimens in Shenzhen Museum

Biological specimens play an important role in cultural exchange, science popularization, scientific research and economic window, but the preparation and preservation technology system of biological specimens is relatively unsafe and inefficient. Mold grows seriously on animal specimens, which is not only harmful to human beings’ health and environment, but also is one of the factors that restricts the development of the natural history museums where these specimens are kept. This paper identified the mold species of animal specimens by PCR with ITS primers, bio-micro-scopic observation, sequencing and phylogenetic tree analysis. The results showed the mold of animal specimens mainly belonged to Aspergillus and Neurospora. This study established the foundations of controlling and restoring the mold that infected animal specimens and guided a new methodology of preparation and environmental friendly exhibition for animal specimens.

Buildings and civil engineering works-Sealants-Determination of changes in cohesion and appearance of elastic weatherproofing sealants after exposure of statically cured specimens to artificial weathering and mechanical cycling

Foreword ISO(the International Organization for Standardization)is a worldwide federation of national standards bodies(ISO member bodies).The work of preparing International Standards is normally carried out through ISO technical committees.Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee.

The Role of Anatomical Specimens in the Teaching of Anatomy

characteristics,complex content,and it is difficult to understand.In view of the nature of the subject,many different models and specimens are required during teaching,increasing the difficulty of its teaching.Although the mode of medical teaching is constantly updating,anatomical specimens are still important in the teaching of anatomy,as they help students to understand the organs,their positions,and structural forms as well as to better grasp the theoretical aspect.In addition,anatomical specimens and medical students contact condition can affect the teaching effect.Therefore,it is imperative to give full play to the role of anatomical specimens in anatomy teaching to improve the teaching effect.This paper summarizes the research on the use of anatomical specimens in the teaching of anatomy.

A CATASTROPHE ANALYSIS ON THE STABILITY OF THE CRACK GROWTH IN THREE-POINT BENDING SPECIMENS

This paper presents an attempt at the application of catastrophe theory to the stabilityanalysis of J-controlled crack growth in three-point bending specimens. By introducing the solutions ofJ-integral in the completely yielding state for the ideal plastic material, the critical condition of losingstability for the crack propagation in the specimen is obtained, based on the cusp catastrophe theory.The process of the crack growth from geometrical sense is described.

Catalogue of the Type Specimens of Amphibians and Reptiles in the Herpetological Museum of Chengdu Institute of Biology, Chinese Academy of Sciences: I. Rhacophoridae(Anura, Amphibia)

In order to facilitate herpetological research for all the herpetologists both in and outside of China, we will report all the type specimens of amphibia and reptilia deposited in the Herpetological Museum of Chengdu Institute of Biology(CIB), Chinese Academy of Sciences in series. This report focuses on the family Rhacophoridae of Anura in Amphibia, including 13 species. The contents of the report include synonym lists and generic transfer of type species, measurements of type specimens, particularly for those with no previously published measurement data, and chromosomal data for each species.

Catalogue of the Type Specimens of Amphibians and Reptiles in the Herpetological Museum of the Chengdu Institute of Biology,Chinese Academy of Sciences:Ⅱ.Hynobiidae (Amphibia,Urodela)

In order to facilitate herpetological research for herpetologists in and outside of China,we will report all the type specimens of Amphibia and Reptilia deposited in the Herpetological Museum of the Chengdu Institute of Biology(CIB),Chinese Academy of Sciences(CAS) in series. This report focuses on the type specimens of the family Hynobiidae of Urodela in Amphibia,which comprises seven species. Each entry provides the genus name,species name,information of the original description,the catalog number of holotype,sex,type locality,information of allotype(if any) and paratype,number and distribution of deposited specimens,and comments where they are appropriate.

SHORT FATIGUE CRACK BEHAVIOUR IN ISO-STRESS SPECIMENS

Fatigue tests were made on a vibration machine using specially designed specimens to investi-gate the initiation and propagation features of short fatigue cracks in a weld metal.The spec-imens were triangular in shape so that when loaded as a cantilever beam the surface tensilestress is constant.Test results show that short fatigue cracks mainly originate from slip bandswithin ferrite grains.The development of short fatigue cracks is marked by a gradual increasein crack density with fatigue cycles.Coalescence of short cracks leads to crack propagationand the crack path is predominantly transgranular.

Catalogue of the Type Specimens of Amphibians and Reptiles in the Herpetological Museum of the Chengdu Institute of Biology,Chinese Academy of Sciences:Ⅲ.Snakes Excluding Viperids (Reptilia,Serpentes)

In China,there are over 180 species of snakes in 57 genera and eight families(excluding the family Viperidae). In the Herpetological Museum of the Chengdu Institute of Biology(CIB),Chinese Academy of Sciences,the snake type specimens represent 11 species in 10 genera and three families(Xenopeltidae,Xenodermatidae and Colubridae). As a series of reports on the type specimens of Amphibia and Reptilia deposited in the Herpetological Museum of CIB,this paper focuses on the serpent families excluding Viperidae in the collections at this Museum.

Edge crack growth of mortar plate specimens under uniaxial loading tests

In this paper, a compression-to-tension conversion technique is developed by applying predominant mode I loading test, using a servo-controlled compression system. The technique is applied to thin mortar plate specimens of different widths that include a prefabricated crack on either a single side to facilitate unilateral crack propagation, or prefabricated cracks positioned on both sides asymmetrically with respect to the specimen midpoint to facilitate bilateral crack propagation under direct tensile stress with a loading rate of 0.001 mm/s. The results show that the main pathways of unilateral crack propagation governing specimen failure are fluctuated locally, but present an approximately straight line overall in the absence of pre-existing internal defects. However, the pathways of bilateral crack propagation are relatively complex, although they present similar characteristics. Analysis results suggest that bilateral crack propagation can be basically divided into three stages, i.e. a stage of linear propagation, a stage representing deviation from the other crack, and a stage where one crack approaches either the other crack or approaches the opposite edge of the specimen, and thereby forming a continuous crack through the specimen. In addition, the stressestrain curves of bilateral crack specimens do not vary significantly around the point of peak stress prior to specimen failure, which means that the specimens do not fail instantaneously.

Effect of Hole Density and Confining Pressure on Mechanical Behavior of Porous Specimens:An Insight from Discrete Element Modeling

Hole-like defects are very common in natural rock or coal mass,and play an important role in the failure and mechanical behaviors of rock or coal mass.In this research,multi-holed coal specimens are constructed numerically and calibrated based on UDEC-GBM models.Then,the strength,deformation and failure behavior of the porous specimens are analyzed,with consideration of hole density(P)and confining pressure(σ_(3)).The simulation results are highly consistent with those available experiment results,and show that the compressive strength decreases exponentially with the increasing hole density.The strength loss is mainly caused by the reduction of cohesion when P<P_(cr)(critical hole density)and the reduction of frictional angle when P>P_(cr).Also,the increasing hole density linearly reduces the tangent and secant modulus and causes greater nonlinear deformation of multi-holed specimens.Finally,the failure patterns,coalescence mechanism and damage behavior of the multi-holed specimens are revealed based on the analysis of mesoscopic displacement fields and stress distribution around holes.This research promotes a better understanding of the effects of hole density and confining pressure on the failure and mechanical behavior of porous geomaterials.