bluuebunny/crossref_metadata_2025 huggingface dataset:
Mimovirus Vesicle‐Based Biological Orthogonal Reaction for Cancer Diagnosis
Authors: Ren En , Chu Chengchao , Zhang Yunming , Wang Junqing , Pang Xin , Lin Xiaoning , Liu Chao , Shi Xiaoxiao , Dai Qixuan , Lv Peng , Wang Xiaomin , Chen Xiaoyuan , Liu Gang
Published: June 2020

Herein, a tumor microenvironment (TME)‐responsive mimovirus vesicle (MVV) is engineered to deliver azide motifs (–N3) via the membrane fusion mechanism for cancer diagnosis. As a pH‐responsive functional protein, the spike vesicular stomatitis virus G‐protein (VSVG) is genetically immobilized on surface of cell membrane vesicles. By virtue of the low‐pH activated fusogenic peculiarity of VSVG, the –N3 groups, which are also presented on MVVs via metabolic engineering, can be directly anchored onto the target cells, thus reducing tumor heterogeneity and serving as the bait to amplify the tumor targeting of dibenzocyclooctyne‐modified diagnostic moieties. The potential diagnostic capability of such design is successfully confirmed in three different murine tumor models. Featuring excellent pH‐sensitive fusogenic traits, the developed MVVs show great responsiveness to the slightly acidic TME of solid tumors, providing a universal platform in overcoming tumor heterogeneity for precise cancer diagnosis.
On the truncation criteria in infinite factor models
Authors: Schiavon Lorenzo , Canale Antonio
Published: June 2020

The number of latent factors, in factor analysis, is typically unknown and motivated by a rich literature on priors distributions, which progressively penalize the number of factors in infinite factor models. Adaptive Gibbs samplers that truncate the infinite factor models are typically used for posterior inference. In this paper, we introduce a novel strategy to adaptively truncate the number of factors that is more interpretable, stable and consistent, with respect to standard approaches.
PVD‐Sputteranlagen im ständigen Wandel
Authors: Seyfert Ulf , Heydenreich Uwe
Published: June 2020

Das Magnetronsputtern bietet aufgrund der Vielzahl von Verfahrensvariationen und verwendbaren Schichtmaterialien und ‐kombinationen breite Anwendungsmöglichkeiten in der Industrie. Einen starken Treiber für neue Anwendungen stellt derzeit die Autoindustrie mit dem Fokus auf Elektromobilität dar. Zunehmende technische Anforderungen und steigender Kostendruck müssen in wirtschaftlich tragfähige Anlagenkonzepte übersetzt werden. In dem Artikel werden verschiedene Grundprinzipien der Abscheidung bei Inline‐ und BatchAnlagen für das Magnetron‐Sputtern erläutert, beispielhaft einige Anwendungen und deren Anforderungen beschrieben und ein daraus abgeleitetes Konzept für eine Inline‐Magnetron‐Sputteranlage vorgestellt.
Bovine piroplasmosis‐anaplasmosis and clinical signs of tropical theileriosis in the plains of Djurdjura (north Algeria)
Authors: Ziam Hocine , Kernif Tahar , Saidani Khelaf , Kelanemer Rabah , Hammaz Zoheir , Geysen Dirk
Published: June 2020

The study was conducted during tick activity season over a period of 5 years in the Djurdjura Plains, Algeria. A total of 299 cattle (Holstein, Montbeliard, Fleckvieh and crossbred animals) with clinical signs were included in this study. A total of 171 animals were found positive for at least one pathogen by Giemsa‐stained blood smears examination Theileria annulata (136/299, 45.5%), Babesia bovis (14/299, 4.7%), B. bigemina (3/299, 1.0%) and Anaplasma marginale (12/299, 4.0%) were identified. Six animals were co‐infected by T. annulata and A. marginale. Although no ticks were collected from diseased animals, clinical signs in cattle were hyperthermia (120/136, 88.3%), gluttony followed by anorexia (113/136, 83.1%), lymph node enlargement (99/136, 72.8%), anaemia (82/136, 60.3%), icterus (58/136, 42.6%) and haemoglobinuria (36/136, 26.5%). Gluttony followed by anorexia was considered highly suggestive of an incubation of tropical theileriosis as shown by a higher receptivity index (IR = 0.89–1). This clinical sign is evident in young Montbeliard and young Holstein males with anaemia (IR = 1) and icterus (IR = 0.78–0.81) which is earlier than haemoglobinuria (IR = 0.51–0.54). The incidence of T. annulata was maximum in July (n = 57), as well as B. bovis (n = 6) and A. marginale (n = 13). These results highlight the preponderance of tropical theileriosis in north‐central Algeria, where gluttony followed by anorexia is probably a prodromal symptom during the incubation period of the disease.
K5[InSe4] and K12[InS4]2(S): New Alkali Chalcogenido Indates with [InQ4]5–ortho Anions
Authors: Langenmaier Michael , Wissinger Sarah , Röhr Caroline
Published: June 2020

The new chalcogenido ortho indates(III) K5[InSe4] and K12[InS4]2(S) were synthesized from melts of the elements (Se) [or with S/In2S3 as chalcogen source] at maximum temperatures of 700/800 °C. The two potassium salts, which were characterized by means of X‐ray single crystal structure analysis, contain isolated tetrahedral ortho anions [InQ4]5–. K5[InSe4] crystallizes in a new structure type [monoclinic, space group C2/c, a = 2014.2(2), b = 1553.1(2), c = 1661.1(2) pm, β = 94.716(2)°, Z = 16, R1 = 0.0317]. The complex structure contains two crystallographically different [InSe4]5– tetrahedra [d(In···Se) = 254.3–263.6 pm], which are arranged into 44 [In(1), A] and 32.4.3.4 [In(2), B] nets. These nets are |:ABA'B':| stacked along the a axis. The 11 crystallographically independent K+ ions are coordinated by four (1×), five (3×) and six (7×) selenido anions [d(K–Se) = 309–415 pm]. The crystal structure and the calculated electronic structure of the pure ortho indate K5[InSe4] are compared with the known “double salts” K9[InSe4]2(Se) and K9[InSe4](Se2)(Se), which exhibit selenide (and diselenide) anions in addition to the ortho metallate. Similarly, the new sulfido indate K11[InS4]2(S) contains sulfide anions besides the indate tetrahedra. In the chiral structure (K6[InTe4](Cl)‐type, hexagonal, space group P63mc, a = 1026.22(10), c = 752.34(7) pm, Z = 2, R1 = 0.0332) layers of similarly oriented [InS4] tetrahedra [d(In···Se) = 246.6/248.1 pm] are hexagonally |:AB:| stacked along one threefold axis. The additional sulfide anions are centered in K+ octahedra. In contrast to the isotypic chloride, only every second polyhedron within the columns of face‐sharing K6 octahedra is statistically occupied by a sulfide ion. Both of the two different K positions exhibit a sixfold coordination by sulfide anions, with K–S distances between 307.1 and 382.1 pm. In the two title compounds, each of the [InQ4] tetrahedra is overall enclosed by 18 potassium cations. The crystal chemistry of the new indates is discussed and compared with that of the (yet comparatively low number) of alkali chalcogenido metallates(III) of Fe, Al and Ga containing isolated metallate tetrahedra.
Combining Performance with Thermal Stability: Synthesis and Characterization of 5‐(3,5‐Dinitro‐1H‐pyrazol‐4‐yl)‐1H‐tetrazole and its Energetic Derivatives
Authors: Benz Maximilian , Klapötke Thomas M. , Stierstorfer Jörg
Published: June 2020

In this study, we present the synthesis of 5‐(3,5‐dinitro‐1H‐pyrazol‐4‐yl)‐1H‐tetrazole and its energetic derivatives starting from 4‐amino‐3,5‐dinitropyrazole, which was diazotized and cyanide substituted. A subsequent cycloaddition reaction with sodium azide led to 5‐(3,5‐dinitro‐1H‐pyrazol‐4‐yl)‐1H‐tetrazole (3). Several alkaline metal and nitrogen‐rich salts were prepared and characterized by low‐temperature X‐ray diffraction. Additionally, all compounds were analyzed by vibrational spectroscopy (IR), 1H, 13C and 14N NMR spectroscopy, elemental analysis and differential thermal analysis (DTA). Additionally, the heats of formation for selected compounds were calculated using the atomization method based on CBS‐4M enthalpies as well as important detonation parameters by using the EXPLO5 code (V6.05). Furthermore, the sensitivities of 3 and all synthesized salts toward friction, impact and electrostatic discharge according to BAM (Bundesamt für Materialforschung) were determined and compared to RDX.
Should Total Thyroidectomy Be Recommended for Patients with Familial Non‐medullary Thyroid Cancer?
Authors: Kim Yon Seon , Seo Minjung , Park Seol Hoon , Ju So Yeon , Kim Eun Sook
Published: June 2020

Background

It is unknown whether familial non‐medullary thyroid cancer (FNMTC) has more aggressive clinical features and a worse prognosis than sporadic non‐medullary thyroid cancer (SNMTC).

Methods

We retrospectively reviewed 2894 patients with differentiated thyroid cancer who underwent primary thyroidectomy, identified 391 FNMTC cases, and compared the prevalence, surgical extension, and clinicopathologic features of FNMTC and SNMTC.

Results

A family history of thyroid cancer was noted in 391 patients (13.5%), with 85% having two affected relatives and 15% with ≥3 affected relatives. A sibling was affected in 52.9% of cases, and in 47.1%, both parent and child were affected. There were no significant between‐group differences in sex, age, tumor size, extrathyroidal extension, or central lymph node metastases. Significantly more patients with FNMTC exhibited multifocal disease (p = 0.020) or benign nodules (p = 0.015). Lateral neck lymph node metastases were noted in 6.6% (SNMTC) and 9.7% (FNMTC, p = 0.021) of patients. Multifocality and combined benign masses were more frequently observed in patients with FNMTC in multivariate analysis. In the FNMTC group, seven experienced disease recurrence, with no mortality noted during follow‐up.

Conclusions

FNMTC is not more aggressive than SNMTC; however, FNMTC should be treated with total thyroidectomy because of the increased disease multifocality and the presence of benign nodules. Lateral neck lymph node metastases were more likely in patients with FNMTC, although we could not estimate prognosis. All patients with thyroid cancer should be checked for family disease history and undergo preoperative ultrasonography to determine the extent of node dissection and the need for total thyroidectomy.
First evidence for the antitumor activity of nanoliposomal irinotecan with 5-fluorouracil and folinic acid in metastatic biliary tract cancer
Authors: Taghizadeh Hossein , Unseld Matthias , Schmiderer Andreas , Djanani Angela , Wilthoner Klaus , Buchinger Dieter , Prager Gerald W.
Published: June 2020

Background

Therapeutic options are limited for advanced, metastatic biliary tract cancer. The pivotal NAPOLI-1 trial demonstrated the superior clinical benefit of nanoliposomal irinotecan (Nal-IRI) in gemcitabine-pretreated patients with metastatic pancreatic ductal adenocarcinoma; however, the antitumor activity of Nal-IRI in biliary tract cancer is unknown. This is the first report describing the efficacy of Nal-IRI in biliary tract cancer.

Methods

In this multicenter retrospective cohort analysis, we identified patients with metastatic biliary tract adenocarcinoma who were treated with Nal-IRI in combination with 5-fluorouracil and folinic acid following tumor progression under standard therapy at one of the study centers between May 2016 and January 2019. We assessed disease control rate (DCR), progression-free survival (PFS), and overall survival (OS).

Results

There were 14 patients; the median age at the time of diagnosis and the median age at the initiation of Nal-IRI were 59.3 and 60.0 years, respectively. Nal-IRI in combination with 5-fluorouracil and folinic acid was administered as second-, third-, fourth-, and fifth-line treatment in 6 (43%), 5 (36%), 2 (14%), and 1 (7%) patient with metastatic disease, respectively. The objective DCR with Nal-IRI was 50% (7/14 patients). Six patients (43%) had partial response, and one patient (7%) had stable disease. Progressive disease was observed in seven patients. The median PFS and median OS following Nal-IRI initiation were 10.6 and 24.1 months, respectively.

Conclusions

This retrospective analysis provides the first evidence that Nal-IRI might exhibit a clinical meaningful antitumor activity in metastatic biliary tract cancer.
A framework for describing interaction between human operators and autonomous, automated, and manual control systems
Authors: Lundberg Jonas , Johansson Björn J. E.
Published: June 2020

This paper addresses how to describe critical episodes of interaction between human operators and autonomous, automated, and manual control systems. The first part of the paper poses three questions: (1) what levels of cognitive control are important to include in a descriptive framework for joint human-autonomy in process control; (2) how should one describe temporal developments in joint socio-technical systems; and (3) how does one analyse communication and control at the system joints. The paper proceeds by proposing a new framework for description and analysis, the Joint Control Framework (JCF), with a simple notation, the Score (JCF-S). It allows descriptions of the three previously mentioned aspects through three analytical activities: process mapping (PM), analysis of Levels of Autonomy in Cognitive Control (LACC), and temporal descriptions of human–machine interaction (T-HMI) through the Score notation. This facilitates analyses across cases and domains. The framework is discussed based on an analysis of two episodes; one work episode (from an air traffic control tower simulator); and one work procedure (from an unmanned traffic management system design concept).
Pituitary society guidance: pituitary disease management and patient care recommendations during the COVID-19 pandemic—an international perspective
Authors: Fleseriu Maria , Buchfelder Michael , Cetas Justin S. , Fazeli Pouneh K. , Mallea-Gil Susana M. , Gurnell Mark , McCormack Ann , Pineyro Maria M. , Syro Luis V. , Tritos Nicholas A. , Marcus Hani J.
Published: June 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the viral strain that has caused the coronavirus disease 2019 (COVID-19) pandemic, has presented healthcare systems around the world with an unprecedented challenge. In locations with significant rates of viral transmission, social distancing measures and enforced ‘lockdowns’ are the new ‘norm’ as governments try to prevent healthcare services from being overwhelmed. However, with these measures have come important challenges for the delivery of existing services for other diseases and conditions. The clinical care of patients with pituitary disorders typically involves a multidisciplinary team, working in concert to deliver timely, often complex, disease investigation and management, including pituitary surgery. COVID-19 has brought about major disruption to such services, limiting access to care and opportunities for testing (both laboratory and radiological), and dramatically reducing the ability to safely undertake transsphenoidal surgery. In the absence of clinical trials to guide management of patients with pituitary disease during the COVID-19 pandemic, herein the Professional Education Committee of the Pituitary Society proposes guidance for continued safe management and care of this population.
Epistemic injustice in mathematics education
Authors: Tanswell Fenner Stanley , Rittberg Colin Jakob
Published: June 2020

Equity and ethics in the learning of mathematics is a major topic for mathematics education research. The study of ethics and injustice in relation to epistemic pursuits, such as mathematics, is receiving a great deal of interest within contemporary philosophy. We propose a bridging project between these two disciplines, importing key ideas of “epistemic injustice” and “ethical orders” from philosophy into mathematics education to address questions of ethics, equity, values and norms. We build on Dawkins and Weber’s (Educ Stud Math 95:123–142, 2017) “apprenticeship model” of learning proofs and proving, which says that mathematics education should reflect the practices of research mathematicians. Focusing on the norms and values implicit in mathematical proving, we argue that deploying this model unreflectively can lead to “epistemic injustices” in which learners are disadvantaged based on their cultural or class background. We propose thinking about the problem in terms of Max Weber’s “ethical orders”, and the clash that arises between the ethical orders of mathematics and the existing ethical orders of the learners and teachers of mathematics. Weber’s lesson is that sometimes these clashes have no overarching resolution, and so the mathematics classroom may also have to settle for tailored pragmatic measures to combat individual cases of epistemic injustice.
A Bayesian Estimation of Child Labour in India
Authors: Kim Jihye , Olsen Wendy , Wiśniowski Arkadiusz
Published: June 2020

Child labour in India involves the largest number of children in any single country in the world. In 2011, 11.8 million children between the ages of 5 and 17 were main workers (those working more than 6 mo) according to the Indian Census. Our estimate of child labour using a combined-data approach is slightly higher than that: 13.2 million (11.4–15.2 million) for ages 5 to 17. There are various opinions on how best to measure the prevalence of child labour. In this study, we use the International Labour Organization (ILO)‘s methodology to define hazardousness and combine it with the most recent United Nations Children’s Fund (UNICEF)‘s time thresholds for economic work and household chores. The specific aims of this study are to estimate the prevalence of child labour in the age group 5 to 17 and to suggest a combined-data approach using Bayesian inference to improve the accuracy of the child labour estimation. This study combines the National Sample Survey on Employment and Unemployment 2011/12 and the India Human Development Survey 2011/12 and compares the result with the reported figures for the incidence of child labour from the Indian Census. Our unique combined-data approach provides a way to improve accuracy, smooth the variations between ages and provide reliable estimates of the scale of child labour in India.
I, Robot: How Human Appearance and Mind Attribution Relate to the Perceived Danger of Robots
Authors: Müller Barbara C. N. , Gao Xin , Nijssen Sari R. R. , Damen Tom G. E.
Published: June 2020

Social robots become increasingly human-like in appearance and behaviour. However, a large body of research shows that these robots tend to elicit negative feelings of eeriness, danger, and threat. In the present study, we explored whether and how human-like appearance and mind-attribution contribute to these negative feelings and clarified possible underlying mechanisms. Participants were presented with pictures of mechanical, humanoid, and android robots, and physical anthropomorphism (Studies 1–3), attribution of mind perception of agency and experience (Studies 2 and 3), threat to human–machine distinctiveness, and damage to humans and their identity were assessed for all three robot types. Replicating earlier research, human–machine distinctiveness mediated the influence of anthropomorphic appearance on the perceived damage for humans and their identity, and this mediation was due to anthropomorphic appearance of the robot. Perceived agency and experience did not show similar mediating effects on human–machine distinctiveness, but a positive relation with perceived damage for humans and their identity. Possible explanations are discussed.
Acceptability and Feasibility of a Guided Biopsychosocial Online Intervention for Cancer Patients Undergoing Chemotherapy
Authors: Grapp Miriam , Rosenberger Friederike , Hemlein Elena , Klein Eva , Friederich Hans-Christoph , Maatouk Imad
Published: June 2020

Chemotherapy is a physically and psychologically highly demanding treatment, and specific Internet-based interventions for cancer patients addressing both physical side effects and emotional distress during chemotherapy are scarce. This study examined the feasibility and acceptability of a guided biopsychosocial online intervention for cancer patients undergoing chemotherapy (OPaCT). A pre-post, within-participant comparison, mixed-methods research design was followed. Patients starting chemotherapy at the outpatient clinic of the National Center for Tumor Diseases in Heidelberg, Germany, were enrolled. Feasibility and acceptability were evaluated through intervention uptake, attrition, adherence and participant satisfaction. As secondary outcomes, PHQ-9, GAD-7, SCNS-SF34-G and CBI-B-D were administered. A total of N = 46 patients participated in the study (female 76.1%). The age of participants ranged from 29 to 70 years (M = 49.3, SD = 11.3). The most prevalent tumour diseases were breast (45.7%), pancreatic (19.6%), ovarian (13.1%) and prostate cancer (10.8%). A total of N = 37 patients (80.4%) completed the OPaCT intervention. Qualitative and quantitative data showed a high degree of participant satisfaction. Significant improvements in the SCNS-SF34 subscale ‘psychological needs’ were found. Study results demonstrate the feasibility and acceptability of the intervention. The results show that OPaCT can be implemented well, both in the treatment process and in participants’ everyday lives. Although it is premature to make any determination regarding the efficacy of the intervention tested in this feasibility study, these results suggest that OPaCT has the potential to reduce unmet psychological care needs of patients undergoing chemotherapy.
The first case of COVID-19 pneumonia in a hemodialysis patient in Japan
Authors: Kuroki Yusuke , Hiyama Kazutoshi , Minami Junya , Takeuchi Miyoshi , Shojima Masumi , Matsueda Shumei , Nagae Hiroshi , Nakano Toshiaki
Published: June 2020

On 31 December 2019, cases of pneumonia whose cause was later identified as SARS-CoV-2 were detected in Wuhan City, Hubei Province of China, and now COVID-19 has spread worldwide. On March 1, 2020, a 69-year-old Japanese man who had been on hemodialysis for 3 years was diagnosed as having COVID-19 pneumonia and hospitalized at our Medical Center. Pulmonary CT revealed bilateral multiple consolidation with bilateral pleural effusion. Aggressive weight reduction was needed to improve the patient’s respiratory condition. Hemodialysis therapy was performed in isolation with hydroxychloroquine administration, but the formation of a dialysis membrane clot forced the withdrawal of dialysis therapy. Changing the dialysis membrane material and anticoagulant enabled the resumption of dialysis therapy, allowing the body weight to correct downward. On the 5th hospitalization day, the patient’s fever dropped and he showed improved oxygenation and chest X-ray. He was eventually discharged. The hydroxychloroquine and appropriate fluid management may have contributed to the patient’s recovery. Clinicians should pay close attention to avoid dialysis-related problems when treating a patient with COVID-19.
Organisational Security Dependent on Individual Privacy
Authors: Danciu Vitalian
Published: June 2020

The global proliferation of cloud computing, smart homes, the internet of things and machine learning requires a novel view on the flow of confidential information and its classification. The security of an organisation is affected by the privacy enjoyed by its members. Sufficient data on those members can be leveraged in a so-called abduction attack aiming to extract confidential information from the organisation. To illustrate it we develop a model of actors and data flows and discuss three scenarios in which the confidentiality achievable by an organisation is limited by the privacy of its members. We support the model and the attack scenarios by reviews of the most prolific sources of personal data, its handling and its perceived value to the individuals it pertains to.
Machine learning for the prediction of antimicrobial stewardship intervention in hospitalized patients receiving broad-spectrum agents
Authors: Bystritsky Rachel J. , Beltran Alex , Young Albert T. , Wong Andrew , Hu Xiao , Doernberg Sarah B.
Published: June 2020

Objective:

A significant proportion of inpatient antimicrobial prescriptions are inappropriate. Post-prescription review with feedback has been shown to be an effective means of reducing inappropriate antimicrobial use. However, implementation is resource intensive. Our aim was to evaluate the performance of traditional statistical models and machine-learning models designed to predict which patients receiving broad-spectrum antibiotics require a stewardship intervention.

Methods:

We performed a single-center retrospective cohort study of inpatients who received an antimicrobial tracked by the antimicrobial stewardship program. Data were extracted from the electronic medical record and were used to develop logistic regression and boosted-tree models to predict whether antibiotic therapy required stewardship intervention on any given day as compared to the criterion standard of note left by the antimicrobial stewardship team in the patient’s chart. We measured the performance of these models using area under the receiver operating characteristic curves (AUROC), and we evaluated it using a hold-out validation cohort.

Results:

Both the logistic regression and boosted-tree models demonstrated fair discriminatory power with AUROCs of 0.73 (95% confidence interval [CI], 0.69–0.77) and 0.75 (95% CI, 0.72–0.79), respectively (P = .07). Both models demonstrated good calibration. The number of patients that would need to be reviewed to identify 1 patient who required stewardship intervention was high for both models (41.7–45.5 for models tuned to a sensitivity of 85%).

Conclusions:

Complex models can be developed to predict which patients require a stewardship intervention. However, further work is required to develop models with adequate discriminatory power to be applicable to real-world antimicrobial stewardship practice.
Scanning Electron Microscopy of Trachea Infected in Vitro in Organ Culture and in Vivo with Avian Infectious Bronchitis Virus
Authors: Dutta S. K. , Johnson R. B.
Published: June 2020

Studies were conducted with chicken tracheas infected in vivo and in vitro with infectious bronchitis virus. For vivo studies, chickens were infected intratracheally with the virus. At intervals, they were sacrificed, tracheal rings were cut in 1-1.5 mm widths, washed, examined in the light microscope for ciliary movement and processed for scanning electron microscopy (SEM). For in vitro studies, tracheal rings of similar dimension were planted in tissue culture media and were infected with the virus. At intervals the tracheal rings were examined in the light microscope for ciliary movement and processed for SEM.
Pathology of Bone Cells in Pigs with Experimental Turbinate Osteoporosis (Bordetella rhinitis)
Authors: Fetter A. W. , Switzer W. P. , Capen C. C.
Published: June 2020

Atrophic rhinitis in swine is a disease of uncertain etiology and is characterized by deformity and reduction in volume of the nasal turbinates. Previous investigations in our laboratory indicated that the fundamental lesion responsible for the localized osteoporotic lesion in the nasal turbinates of pigs with the naturally occurring and experimentally induced disease was reduced bone formation. The experimental disease was produced by inoculating pigs with a pooled suspension of mascerated nasal turbinates obtained from pigs with the naturally occurring disease. Although a number of factors have been suggested as the cause of porcine atrophic rhinitis, there now is considerable evidence that Bordetella bronchiseptica is a major cause of this disease. Bordella bronchiseptica consistently produces atrophy of the nasal turbinates when inoculated intranasally in young pigs and can be isolated from a large number of swine with clinical signs and lesions characteristic of atrophic rhinitis.
High Voltage Electron Microscopy of Ion-Milled Dental Enamel
Authors: Ackerman L. D. , Wei S. H. Y.
Published: June 2020

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.

A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.
The Intracellular Morphology of Yeast Mitochondria Studied by HVEM
Authors: Davison M. T. , Garland P. B.
Published: June 2020

Ultra-thin sections of suitably grown, fixed and stained yeast cells examined by electron microscopy typically show several mitochondrial profiles per cell section; such observations are usually interpreted as showing several separate mitochondria per cell. Variations in the size and number of mitochondria per cell at different stages of batch culture have been described. The possibility arises that examination of ultra-thin sections failed to distinguish between profiles of individual rounded mitochondria and profiles of much larger cylindrical mitochondria looped across the plane of the section.
Observations on Developing Blood Vessels in Rat Spinal Cord—A High Voltage Electron Microscopy Study
Authors: Hannah Richard S.
Published: June 2020

The formation of junctional complexes between endothelial cell processes was examined in rat spinal cords, from age birth to six weeks. Segments of spinal cord were removed from the region of the cervical enlargement and fixed. For comparative purposes, animals from each time group were subdivided into groups, fixed by either immersion or perfusion with an aldehyde combination in sodium cacodylate buffer and embedded in Araldite. Thin sections were examined by conventional transmission electron microscopy. Thick sections (0.5μ - 1.0μ) were stained with uranyl magnesium acetate for four hours at 60°C and lead citrate for 30 mins. and examined in the AEI Mark II High Voltage Electron Microscope.
Preparation of Single Cells for Correlative High Voltage and Scanning Electron Microscopy
Authors: Barber T. A.
Published: June 2020

Scanning electron microscopy (SEM) has made a great deal of information on surface structure of isolated cells available, but no methods presently in use allow SEM information on cell surface structure to be directly correlated with internal cell ultrastructure. This situation is particularly unfortunate in the case of white blood cells which have historically been classified on the basis of internal morphology. We have found high voltage electron microscopy (HVEM) useful ingathering information on the morphology of unsectioned leukocytes due to the great penetrating power of the 1000 KV beam. Utilizing the technique discussed below, we have been able to obtain correlation of information gathered from single cells by HVEM with that obtained from the same cells using SEM.
Utilizing Dark Field Electron Microscopy to Produce Lantern Slides
Authors: Meador J. N. , Sun C. N. , White H. J.
Published: June 2020

The electron microscope is being utilized more and more in clinical laboratories for pathologic diagnosis. One of the major problems in the utilization of the electron microscope for diagnostic purposes is the time element involved. Recent experimentation with rapid embedding has shown that this long phase of the process can be greatly shortened. In rush cases the making of projection slides can be eliminated by taking dark field electron micrographs which show up as a positive ready for use. The major limiting factor for use of dark field micrographs is resolution. However, for conference purposes electron micrographs are usually taken at 2.500X to 8.000X. At these low magnifications the resolution obtained is quite acceptable.
Ion Beam Etching of Cellular Material
Authors: Spector M. , Burns L. C. , Kimzey S. L.
Published: June 2020

The ion beam etching of cellular material was studied by examining uncoated cells during the course of etching in the specimen chamber of a scanning electron microscope. Repeated examination of the cells during etching faciliated the interpretation of features in the etched surface.

Cells were initially fixed in glutaraldehyde prior to being dispersed in a monolayer on a conductive silicon wafer originally used as a substrate for electron microprobe specimens. The cells were subsequently dehydrated in ethanol and critical point dried in carbon dioxide. Etching was carried out in the specimen chamber of an ETEC scanning electron microscope using an ETEC ion beam etching device. An 18 KV argon ion beam with a 40° angle of incidence was utilized for etching. The cells were rotated at about 4 rpms. Etching was interrupted at specific time intervals and the cells were examined as they remained uncoated in the specimen chamber. Ten through 20 KV electron beams were used to examine the cells.
Leydig Cell Morphology After Unilateral Vasectomy in the Rat. A Qualitative and Quantitative Study
Authors: V.M.D. Pablo Hernández Jáuregui , V.M.D. Jorge Olivera
Published: June 2020

Leydig cells are known to be the main source of steroids in testicles. The agranular endoplasmic reticulum which in Leydig cells is abundant, has been considered to be the source and place of metabolism of steroids. One of the methods utilized in the male to control human population growth, is the vasectomy. Since many vasectomized men had improved their sexual behaviour, a matter that according to Phoenix is mediated by psychological factors, the question, that if Leydig cells are modified after vasectomy is still unanswered. We decided to find out the possible changes in Leydig cells if any, after the vasectomy.
Electron Microscopic Study of the Epithelium of the Seminal Vesicle of Aging Rats
Authors: Allison V. F. , Fink G. C. , Cearley G. W.
Published: June 2020

It is well known that epithelial hyperplasia (benign hypertrophy) is common in the aging prostate of dogs and man. In contrast, little evidence is available for abnormal epithelial cell growth in seminal vesicles of aging animals. Recently, enlarged seminal vesicles were reported in senescent mice, however, that enlargement resulted from increased storage of secretion in the lumen and occurred concomitant to epithelial hypoplasia in that species.

The present study is concerned with electron microscopic observations of changes occurring in the pseudostratified epithelium of the seminal vescles of aging rats. Special attention is given to certain non-epithelial cells which have entered the epithelial layer.
Scanning Electron Microscopic Studies on the Tegument of Trematodes
Authors: Ubelaker J. E. , Specian R. D. , Allison V. F.
Published: June 2020

Among the parasitic flatworms, only members of the trematoda have exploited nearly every conceivable niche. Since physiological demands in each habitat present special problems in eluding the host response as well as obtaining nourishment the surface epithelia of such organisms warrant special attention. To gain an appreciation of tegumental diversity in the trematoda, representative trematodes from numerous habitats in their respective hosts were examined by scanning electron microscopy

Specimens were collected from natural infections, fixed in paraformaldehyde and dehydrated in alcohol. Ethanol was exchanged with amyl acetate prior to CO2 drying in a Denton DCP-1 critical point dryer. The dried specimens were mounted on metal holders, outgassed and rotary coated with gold-palladium. These were then examined with the ISI Mini-SEM and AMR 1000 scanning electron microscopes.
Fractographic Studies of the Honey Bee Sensilla Coeloconica and Sensilla Amupullacea Campaniformia by SEM
Authors: Dietz Alfred , Anderson Leroy M. , Sanford Malcolm T.
Published: June 2020

The antennal sensory organs of honey bees have been studied by many researchers in the past. In most instances their work was confined to readily identifiable cuticular sensory structures such as the pore plate organ (Figs. 1, 3) and several types of hair-like sensilla (Fig. 1). The total number of receptors on a honey bee antennae is roughly 13,000 of which about 8,200 belong to the hair-like receptors or s. trichodea group (Fig. 1). The pore plate organs or s. placodea comprise the next largest group with 3,000 receptors. The pit peg sense organs or s. ampullacea (Figs. 3, 5), and s. coeloconica (Figs. 1, 2) are present in considerably smaller number (approximately 300) and have received little attention since they cannot be readily identified on the basis of their surface structure. Thus, little is known about the fine structure of these pit peg organs. In this study, pit peg organs of plastic embedded antennae were examined by scanning electron microscopy.
Chondriosphere Formation and Their Degeneration in Alcoholic Myocardiopathy
Authors: Sekhri K.K. , Alexander C.S. , Nagasawa H.T.
Published: June 2020

Previously, we reported the formation of giant mitochondria or chondriospheres 1n the myocardium of rats fed alcohol diet and 15% ethanol ad lib. For the present report, twenty-four C57BL male mice were randomly divided into three groups: Group I was fed sweetened semisynthetic liquid alcohol diet in which 36 per cent of the calories were derived from alcohol; Group II was maintained on a similar diet but alcohol was isocalorically substituted by sucrose, and Group III was fed regular Guilford mouse chow diet and distilled water ad 11b for 25 weeks.
Scanning Electron Microscopy of Murine Oncornavirus Infected Cells
Authors: Panem S. , Lin P.S.D. , Crewe A. V. , Kirsten W. H.
Published: June 2020

Although oncornaviruses have been the subject of numerous transmission electron microscopic studies, questions concerning virion structure and the maturation of virus at the infected cell membrane remain unanswered. We have begun to study viral morphogenesis with particular emphasis on the distribution of viral budding sites and the appearance of virus during maturation using scanning electron microscopy.
Biophysical Measurement of Molecular Weight of Foot-and-Mouth Disease RNA Fragments
Authors: Breese Sydney S. , Bachrach Howard L.
Published: June 2020

Continuing studies on the physical and chemical properties of foot-and-mouth disease virus (FMDV) have included electron microscopy of RNA strands released when highly purified virus (1) was dialyzed against demlneralized distilled water. The RNA strands were dried on formvar-carbon coated electron microscope screens pretreated with 0.1% bovine plasma albumin in distilled water. At this low salt concentration the RNA strands were extended and were stained with 1% phosphotungstic acid. Random dispersions of strands were recorded on electron micrographs, enlarged to 30,000 or 40,000 X and the lengths measured with a map-measuring wheel. Figure 1 is a typical micrograph and Fig. 2 shows the distributions of strand lengths for the three major types of FMDV (A119 of 6/9/72; C3-Rezende of 1/5/73; and O1-Brugge of 8/24/73.
Two New Cell Types in the Retina of a Snail Helix aspersa
Authors: Brandenburger Jean L. , Eakin Richard M.
Published: June 2020

Previous studies have described the retina of the common garden snail Helix aspersa to be composed of two cell types: sensory and pigmented. We have now found a third, a ganglion cell, and another kind of sensory cell, both heretofore undescribed.

Ganglion cells (Fig. 1) are large (11-16 fan in diameter), ovoid, and few in number. We estimate about 12 per eye. They occur only along the periphery of the retina. Each possesses a large spherical nucleus centrally situated in an electron lucent cytoplasm which contains numerous organelles and in clusions: mitochondria, Golgi bodies, EH, lysosomes, glycogen granules, microtubules, ribosomes, fine filaments and clusters of irregular vesicles. These vesicles (insert, Fig. 1) vary in size (500 A to 1200 A in diameter) and density (clear, granular or dense-cored).
Hard Palate Ultrastructure
Authors: Dockum Norman L. , Dockum John G.
Published: June 2020

Ultrastructural characteristics of the hard palate of six New Zealand white rabbits were investigated utilizing normal fixation with 2.0% osmium tetraoxide followed by staining with uranyl acetate and lead citrate.

Basal epithelial cells from the palatal mucous membrane were observed to have hemidesmosomes at points of attachment to the basal lamina with apparent fibrillar structures from the lamina propria entering the lamina densa. The lamina lucida appears to have extensions of similar filaments which enter it from the lamina densa. The lamina propria is for the greatest part composed of collagen fibers, blood vessels, nerves, fibroblasts and histiocytes.
The High Resolution Scanning Transmission Electron Microscope
Authors: Crewe A. V.
Published: June 2020

The high resolution STEM is now a fact of life. I think that we have, in the last few years, demonstrated that this instrument is capable of the same resolving power as a CEM but is sufficiently different in its imaging characteristics to offer some real advantages.

It seems possible to prove in a quite general way that only a field emission source can give adequate intensity for the highest resolution^ and at the moment this means operating at ultra high vacuum levels. Our experience, however, is that neither the source nor the vacuum are difficult to manage and indeed are simpler than many other systems and substantially trouble-free.
Non-Conventional Electron Microscopy in Small Defect Characterization
Authors: Seshan K.
Published: June 2020

The conventional bright field (Fig. 1a) and dark-field images of small (<200Å) def ects are beset with several disadvantages: The image sizes (≃300Å) are two or three times the defect size; the image shift from core position may be larger than the defects; (Table 1a); the images are dominated by strain field effects and give no clue to defect shape and habit. Conventional images are therefore unsuitable for the size, nature and habit plane determination of small defects.
Development of 200 kV Scanning-Transmission Electron Microscope
Authors: Koike H. , Sakurai S. , Ueno K. , Watanabe M.
Published: June 2020

In recent years, there has been increasing demand for higher voltage SEMs, in the field of surface observation, especially that of magnetic domains, dislocations, and electron channeling patterns by backscattered electron microscopy. On the other hand, the resolution of the CTEM has now reached 1 ∼ 2Å, and several reports have recently been made on the observation of atom images, indicating that the ultimate goal of morphological observation has beem nearly achieved.
Combined Analytical Techniques for the ELMISKOP 101 and 102
Authors: Thieringer H.M. , Weichan C.
Published: June 2020

The high performance transmission electron microscopes ELMISKOP 101 and 102 are increasingly used in the analytical field. This is especially favoured by the fact that five different analysis and imaging modes can be adopted by optional accessories: for wavelength dispersive X-ray microanalysis, energy dispersive X-ray microanalysis, scanning transmission electron microscopy (STEM), scanning electron microscopy (SEM) by secondary electrons, and image current measurement.
Some Precision Electronics for a Scanning Transmission Electron Miscroscope
Authors: Zubin J. A. , Woodruff D. C. , Wiggins J. W.
Published: June 2020

A one ppm stability 100 KV power supply has been built using a commercial oil-insulated power supply inside a wide bandwidth feedback loop assembled from readily available commercial components. Several one ppm stability current sources for magnetic lenses and eight deflection coil drivers have also been assembled from commercial components. The following approach was used for all of the power supplies. A precision variable reference was made by buffering a 10.83 V, type R mercury battery. A wide bandwidth, high gain preamplifier was made using the full capabilities of the Fairchild 725 integrated circuit instrumentation amplifier. Precision main feedback and current sampling resistors were used.
A Low Magnification-Large Sample Holder for the SEM
Authors: Ballard David B.
Published: June 2020

The ability of the SEM to obtain low-magnification images (2 to 50x), low barrel distortion (2 to 5%), stereo imaging, comparison microscopy and a large depth of focus exceeding the optical microscope has been demonstrated0) and the related electron optics have been discussed.(2) in most instances, the sample for observation was placed within the specimen chamber at a convenient height and location, and a blank plate used as a substitute for the standard stage.
In situ Chemical Vapor Deposition of Silicon
Authors: Kenty J. L.
Published: June 2020

An AEI EM6 electron microscope was modified for the in situ chemical vapor deposition (CVD) of Si films by pyrolysis of SiH4 gas. The environmental cell was so constructed that 100 μm dia. apertures placed 1.6 mm apart formed the top and bottom of the CVD microchamber and permitted a gas flow of up to 0.4 cm3 (STP)/min at up to 10 torr. A current of 2 amps through a single 200 mesh Ti grid of 0.003 mm2 net cross sectional area is sufficient to heat the sample to ~1200°C. Some temperature-heater power calibration experiments were performed by observing the melting point of evaporated metal films.
Grain Refinement in Titanium-Erbium Alloys
Authors: Rath B. B. , O'Neal J. E. , Lederich R. J.
Published: June 2020

Addition of small amounts of erbium has a profound effect on recrystallization and grain growth in titanium. Erbium, because of its negligible solubility in titanium, precipitates in the titanium matrix as a finely dispersed second phase. The presence of this phase, depending on its average size, distribution, and volume fraction in titanium, strongly inhibits the migration of grain boundaries during recrystallization and grain growth, and thus produces ultimate grains of sub-micrometer dimensions. A systematic investigation has been conducted to study the isothermal grain growth in electrolytically pure titanium and titanium-erbium alloys (Er concentration ranging from 0-0.3 at.%) over the temperature range of 450 to 850°C by electron microscopy.
Enumeration and Identification of Asbestos Fibres in Water
Authors: Mudroch O. , Kramer J. R.
Published: June 2020

Approximately 60,000 tons per day of waste from taconite mining, tailing, are added to the west arm of Lake Superior at Silver Bay. Tailings contain nearly the same amount of quartz and amphibole asbestos, cummingtonite and actinolite in fibrous form. Cummingtonite fibres from 0.01μm in length have been found in the water supply for Minnesota municipalities.

The purpose of the research work was to develop a method for asbestos fibre counts and identification in water and apply it for the enumeration of fibres in water samples collected

(a) at various stations in Lake Superior at two depth: lm and at the bottom.

(b) from various rivers in Lake Superior Drainage Basin.
The Use of Thick Specimens in a STEM
Authors: Groves T. , Crewe A. V.
Published: June 2020

The scanning transmission microscope can be used in a wide variety of different contrast modes by careful choice of detector systems. Many of these contrast modes have already been demonstrated, and their characteristics are fairly well understood when the microscope is used with thin specimens. However, little work has been done on the use of the STEM with thick specimens, and this will become particularly important when our million volt machine is completed.
A Study of Contamination Caused by a Very Narrow Election Beam
Authors: Knox Warren A.
Published: June 2020

Our study of contamination spots was done using the JEM-100B microscope in both the scanning and conventional modes. A very narrow scanning beam known to give a resolution of better than 35Å was focused, with scanning coils deactivated, onto the surface of a thin carbon film for various periods of time. The resulting contamination spots were then shadowed with gold at an angle of 30°, and imaged conventionally. The diameters of the spots were measured directly while the heights were calculated from the shadow lengths. The volumes were then calculated considering the spot to be the frustum of a right circular cone with minor diameter the known resolution of the beam, and major diameter the measured diameter.