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The future of computer-aided sperm analysis

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Asian Journal of Andrology 2015年第4期17卷 545-553页

作者： Sharon T Mortimer Gerhard van der horst david Mortimer Oozoa Biomedical West Vancouver BC Canada Department of Medical Biosciences University ofthe Western Cape Bellville South Africa 0ozoaBiomedical West Vancouver BC Canada.

Computer-aided sperm analysis （CASA） technology was developed in the late 1980s for analyzing sperm movement characteristics or kinematics and has been highly successful in enabling this field of research. CASA has also been used with great success for measuring semen characteristics such as sperm concentration and proportions of progressive motility in many animal species, including wide application in domesticated animal production laboratories and reproductive toxicology. However, attempts to use CASA for human clinical semen analysis have largely met with poor success due to the inherent difficulties presented by many human semen samples caused by sperm clumping and heavy background debris that, until now, have precluded accurate digital image analysis. The authors review the improved capabilities of two modern CASA platforms （Hamilton Thorne CASA-II and Microptic SCA6） and consider their current and future applications with particular reference to directing our focus towards using this technology to assess functional rather than simple descriptive characteristics of spermatozoa. Specific requirements for validating CASA technology as a semi-automated system for human semen analysis are also provided, with particular reference to the accuracy and uncertainty of measurement expected of a robust medical laboratory test for implementation in clinical laboratories operating according to modern accreditation standards.

关键词： HISTORICAL INTRODUCTION

Ineffective oesophageal motility:Manometric subsets exhibit different symptom profiles

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World Journal of Gastroenterology 2008年第23期14卷 3719-3724页

作者： horst Gunter Haack Ross david Hansen Allison Malcolm John Edward Kellow Department of Gastroenterology Gastrointestinal Investigation UnitRoyal North Shore HospitalUniversity of SydneyAustralia

AIM:To compare the demographic and clinical features of different manometric subsets of ineffective oesophageal motility(IOM;defined as ≥ 30% wet swallows with distal contractile amplitude < 30 mmHg) ,and to determine whether the prevalence of gastro-oesophageal reflux differs between IOM subsets. METHODS:Clinical characteristics of manometric subsets were determined in 100 IOM patients(73 female,median age 58 years) and compared to those of 100 age-and gender-matched patient controls with oesophageal symptoms,but normal manometry. Supine oesophageal manometry was performed with an eight-channel DentSleeve water-perfused catheter,and an ambulatory pH study assessed gastro-oesophageal reflux. RESULTS:Patients in the IOM subset featuring a majority of low-amplitude simultaneous contractions(LASC) experienced less heartburn(prevalence 26%) ,but more dysphagia(57%) than those in the IOM subset featuring low-amplitude propagated contractions(LAP;heartburn 70%,dysphagia 24%;both P ≤ 0.01) . LASC patients also experienced less heartburn and more dysphagia than patient controls(heartburn 68%,dysphagia 11%;both P < 0.001) . The prevalence of heartburn and dysphagia in IOM patients featuring a majority of non-transmitted sequences(NT) was 54%(P = 0.04 vs LASC) and 36%(P < 0.01 vs controls) ,respectively. No differences inage and gender distribution,chest pain prevalence,acid exposure time(AET) and symptom/reflux association existed between IOM subsets,or between subsets and controls. CONCLUSION:IOM patients with LASC exhibit a different symptom profile to those with LAP,but do not differ in gastro-oesophageal reflux prevalence. These findings raise the possibility of different pathophysiological mechanisms in IOM subsets,which warrants further investigation.

关键词： Age Dysphagia Heartburn Ineffective oesophageal motility Oesophageal manometry Simultaneous contractions

Principles of Physical Chemistry 2nd ed.

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Extreme biomimetics： A carbonized 3D spongin scaffold as a novel support for nanostructured manganese oxide（IV） and its electrochemical applications

2009年

作者： Kuhn, Hans/ Forsterling, horst-Dieter/ Waldeck, david H.

ISBN: (纸本)9780470089644

Principles of Physical Chemistry, Second Edition uniquely uses simple physical models as well as rigorous treatments for understanding molecular and supramolecular systems and processes. In this way the presentation assists students in developing an intuitive understanding of the subjects as well as skill in quantitative manipulations. The unifying nature of physical chemistry is emphasized in the book by its organization - beginning with atoms and molecules, and proceeding to molecular assemblies of increasing complexity, ending with the emergence of matter that carries information, i.e. the origin of life, a physicochemical process of unique importance. The aim is to show the broad scope and coherence of physical chemistry.

关键词： Chemistry Physical and theoretical.

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Nano Research 2018年第8期11卷 4199-4214页

作者： Tomasz Szatkowski Kacper Kopczynski Mykhailo Motylenko horst Borrmann Beata Mania Matgorzata Gras Grzegorz Lota Vasilii V. Bazhenov david Rafaja Friedrich Roth Juliane Weise Enrico Langer Marcin Wysokowski Sonia Zoltowska-Aksamitowska laroslav Petrenko Serguei L, Molodtsov Jana Hubalkova Christos G. Aneziris Yvonne Joseph Allison L. Stelling Hermann Ehrlich Teofil Jesionowski Institute of Chemical Technology and Engineering Faculty of Chemical Technology Poznan University of Technology Poznan60965 Poland Institute of Chemistry and Technical Electrochemistry Poznan University of Technology Poznan 60965 Poland Institute of Materials Science TU Bergakademie Freiberg Freiberg 09599 Germany Max Planck Institute for Chemical Physics of Solids Dresden 01187 Germany Institute of Experimental Physics TU Bergakademie Freiberg Freiberg 09599 Germany European X-Ray Free-Electron Laser Facility (XFEL) GmbH Schenefeld 22869 Germany Institute of Semiconductors and Microsystems Polymere Mikrosysteme TU Dresden Dresden 01062 Germany Saint-Petersburg National Research University of Information Technologies Mechanics and Optics ITMO University St. Petersburg197101 Russia Institute of Ceramic Glass and Constructions Materials TU Bergakademie Freiberg 09599 Germany Institute of Electronics and Sensor Materials TU. Be.rga.kad. emeFreberg Freib. erg 09599 Germany Department of Biochemistry Duke University MedicaI School Durham North Carolina 27708 USA

Composites containing biological materials with nanostructured architecture have become of great interest in modem materials science, yielding both interesting chemical properties and inspiration for biomimetic research. Herein, we describe the preparation of a novel three-dimensional （3D） nanostructured MnO2-based com- posite developed using a carbonized proteinaceous spongin template by an extreme biomimetics approach. The thermal stability of the spongin-based scaffold fadlitated the formation of both carbonized material （at 650 ℃ with exclusion of oxygen） and manganese oxide with a defined nanoscale structure under 150 ℃. Remarkably, the unique network of spongin fibers was maintained after pyrolysis and hydro^ermal processing, yielding a novel porous support. The MnO2-spongin composite shows a bimodal pore distribution, with macropores originating from the spongin network and mesopores from the nanostructured oxidic coating. Interestingl3~ the composites also showed improved electrochemical properties compared to those of Mno2. Voltammetry cycling demonstrated the good stability of the material over more than 3,000 charging/discharging cydes. Additionally, electrochemical impedance spectroscopy revealed lower charge transfer resistance in the prepared materials. We demonstrate the potential of extreme biomimetics for developing a new generation of nanostructred materials with 3D centimeter-scale architecture for the storage and conversion of energy generated from renewable natural sources.

关键词： nanostructuredcomposite extreme biomimetics spongin scaffold manganese oxide electrochemistry supercapacitor

Comparing dietary determinants of serum vitamin D status among African-Americans and Caucasians

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Open Journal of Epidemiology 2012年第1期2卷 14-21页

作者： Sameer Murali Lenore Arab Alfonso Ang Casey Nelson Katherine Wessling-Perry Patricia Jardack Ronald L. horst General Internal Medicine David Geffen School of Medicine at UCLA Los Angeles USA

African-Americans (AAs) maintain a high prevalence of vitamin D insufficiency compared to Caucasians. The relationship between dietary sources of vitamin D and serum 25-hydroxyvitamin D (25(OH)D) among AAs remains poorly understood. This research examines the dietary determinants of 25(OH)D levels in AAs and Caucasians, controlling for demographic characteristics. 121 Caucasians and 119 AAs participated in a biomarker based study, comparing the correlation of serum 25(OH) D with dietary sources of vitamin D. Diet was assessed by multiple 24-hour (24-hr) recall and Food Frequency Questionnaire (FFQ). Parallel multiple linear and logistic regression models stratified by race were then used to regress 25(OH)D level and sufficiency (25(OH)D > 20 ng/mL) on major dietary sources of vitamin D—multivitamins (MV), milk, and fish—controlling for age, gender, and BMI. Results show that AAs are sensitive to the method of dietary assessment, with multiple 24 hr recall demonstrating highest correlation (0.4) with 25 (OH)D levels. MV’s association with 25(OH)D levels was highest in both groups, 25% higher in AAs vs. Caucasians (8.6 vs. 6.5 ng/mL per 400 IU). Milk’s impact on serum was similar in both groups but fish was only significant among Caucasians. MV consumption significantly increased odds of vitamin D sufficiency in both groups. Given the high prevalence of vitamin D insufficiency and the strong contribution as compared to milk or fish, MV supplementation is recommended. Additionally, future studies aimed at measuring vitamin D intake should consider the use of multiple 24 hr recall instead of a single measure of FFQ or 24 hr recall since the multiple 24 hr recalls have a stronger correlation to serum 25(OH)D.

关键词： Vitamin D Dietary Determinants Fish Vitamin Supplements

Endoscopic hemostasis makes the difference:Angiographic treatment in patients with lower gastrointestinal bleeding

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World Journal of Gastrointestinal Endoscopy 2021年第7期13卷 221-232页

作者： david John Werner Till Baar Ralf Kiesslich Nicolai Wenzel Nael Abusalim Achim Tresch Johannes Wilhelm Rey Radiologie Rhein-Nahe Krankenhaus am St.MarienwörthBad Kreuznach 55543RLPGermany Department of Radiology Helios Dr.Horst-Schmidt-ClinicGermanyWiesbaden 65199HessenGermany Institute for Medical Statistics and Computational Biology Faculty of MedicineUniversity of CologneGermanyCologne 50923NRWGermany Department of Internal Medicine II Helios Dr.Horst-Schmidt-ClinicWiesbadenGermanyWiesbaden 65199HessenGermany Department of Diagnostic and Interventional Radiology Medical Center HanauGermanyHanau 63450HessenGermany CECAD University of CologneGermanyCologne 50923NRWGermany Center for Data and Simulation Science University of CologneGermanyCologne 50923NRWGermany Department of Gastroenterology and Endoscopy Medical Center OsnabrueckGermanyOsnabrueck 49076NiedersachsenGermany

BACKGROUND The large majority of gastrointestinal bleedings subside on their own or after endoscopic ***,a small number of these may pose a challenge in terms of therapy because the patients develop hemodynamic instability,and endoscopy does not achieve adequate *** radiology supplemented with catheter angiography(CA)and transarterial embolization have gained importance in recent *** To evaluate clinical predictors for angiography in patients with lower gastrointestinal bleeding(LGIB).METHODS We compared two groups of patients in a retrospective *** group had been treated for more than 10 years with CA for LGIB(n=41).The control group had undergone non-endoscopic or endoscopic treatment for two years and been registered in a bleeding registry(n=92).The differences between the two groups were analyzed using decision trees with the goal of defining clear rules for optimal *** Patients in the CA group had a higher shock index,a higher Glasgow-Blatchford bleeding score(GBS),lower serum hemoglobin levels,and more rarely achieved hemostasis in primary *** patients needed more transfusions,had longer hospital stays,and had to undergo subsequent surgery more frequently(P<0.001).CONCLUSION Endoscopic hemostasis proved to be the crucial difference between the two patient *** endoscopic hemostasis,along with GBS and the number of transfusions,would permit a stratification of *** prospective confirmation of the present findings,the use of decision trees would permit the identification of patients at risk for subsequent diagnosis and treatment based on interventional radiology.

关键词： Lower gastrointestinal bleeding Endoscopy Angiography Embolization Computed tomography angiography Intervention

Unmasking lower gastrointestinal bleeding under administration of norepinephrine

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World Journal of Radiology 2022年第12期14卷 375-383页

作者： david John Werner Nicolai Wenzel Nael Abusalim Ralf Kiesslich Till Baar Achim Tresch Johannes Wilhelm Rey Department of Radiology Helios Dr.Horst-Schmidt-ClinicWiesbaden 65199HessenGermany Radiologie Rhein-Nahe Krankenhaus St.MarienwörthBad Kreuznach 55543Rheinland-PfalzGermany Department of Diagnostic and Interventional Radiology Medical Center HanauHanau 63450HessenGermany Department of Internal Medicine II Helios Dr.Horst-Schmidt-ClinicWiesbaden 65199HessenGermany Institute for Medical Statistics and Computational Biology Faculty of MedicineUniversity of CologneCologne 50923Nordrhein-WestfalenGermany Department of Gastroenterology and Endoscopy Medical Center OsnabrueckOsnabrueck 49076NiedersachsenGermany

BACKGROUND Bleeding in the gastrointestinal tract is common and transarterial embolization enables the clinician to control gastrointestinal *** extravasation is a prerequisite for successful *** angiography is helpful in the detection of elusive *** We performed a retrospective analysis of angiographic treatment in patients with lower gastrointestinal hemorrhage and initially negative angiographies,as well as the role of norepinephrine(NE)in unmasking *** We analyzed 41 patients with lower gastrointestinal bleeding after angiography who had undergone treatment over a period of 10 *** patients had a positive shock index and needed intensive *** In three of four patients,angiography disclosed the site of bleeding when NE was used during the procedure for hemodynamic *** We suggest that angiography performed after the administration of NE in unstable patients with gastrointestinal bleeding and an initially negative angiography has the potential to unmask bleeding sites for successful ***,this statement must be confirmed in prospective studies.

关键词： Lower gastrointestinal bleeding Endoscopy Provocative angiography Norepinephrine Radiology Gastrointestinal bleeding