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火炸药学报 2016年第2期39卷 16-21页

作者： LEMPERT david b. DALINGER Igor L. SHU Yuan-jie KAZAKOV Anatolii I. SHEREMETEV Aleksei b. Institute of Problems of Chemical Physics Russian Academy of Sciences(IPCP RAS) Moscow 142432 Russia Zelinsky Institute of Organic Chemistry Russian Academy of Sciences Moscow 119991 Russia Xi'an Modern Chemistry Research Institute Xi'an 710065 China

The experimental values of the enthalpy of formation of two isomeric 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles have been obtained(261.5±5.0and 246.4±6.7kJ/mol for crystalline 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles,respectively).The ballistic effectiveness of these potential oxidizers in composite solid propellants was *** is shown that these two oxidizers may be successfully applied in metal-free compositions or with a small content of *** the bottom stage 3,4-dinitro-1-(trinitromethyl)-1H-pyrazole is a bit better than 3,5-dinitro-1-(trinitromethyl)-1H-pyrazole,for the upper stage the both oxidizers show the equal ballistic *** oxidizers allow to create metal-free solid composite propellants with the binder percentage not lower than 19%(volume fraction),with I3spequal to 256.5-257.0sat density equal to 1.72-1.74g/cm^3.

关键词： composite solid propellants high-enthalpy oxidizer energetic parameters estimation specific impulse ballistic effectiveness

Secure data networks for electrical distribution applications

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Journal of Modern Power Systems and Clean Energy 2015年第3期3卷 447-455页

作者： david M.LAVERTY John b.O’RAW Kang LI D.John MORROW School of EEECS Queen’s University Belfast125 Stransmillis RoadBelfast BT95AHUK

Smart Grids are characterized by the application of information communication technology(ICT)to solve electrical energy *** power networks span large geographical areas,thus a necessary component of many Smart Grid applications is a wide area network(WAN).For the Smart Grid to be successful,utilities must be confident that the communications infrastructure is *** paper describes how a WAN can be deployed using WiMAX radio technology to provide high bandwidth communications to areas not commonly served by utility communications,such as generators embedded in the distribution network.A planning exercise is described,using Northern Ireland as a case *** suitability of the technology for real-time applications is assessed using experimentally obtained latency data.

关键词： Telecoms Latency WiMAX Security

Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution position and strength of the donors

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Science China Chemistry 2024年第5期67卷 1613-1623页

作者： Changfeng Si Dianming Sun Tomas Matulaitis david b.Cordes Alexandra M.Z.Slawin Eli Zysman-Colman Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2GCz bP, 2DPACz bP, 2FbP2GCz and 2FbP2DPACz. We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant(kRISC) of the emitters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(bP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DPACz bP, containing stronger donors than 2GCz bP, exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPACz bP doped in m CP emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4Cz IPN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DPACz bP HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrimers

A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health Science 2024年第1期13卷 61-71页

作者： Alex E.Mohr david b.Pyne Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and Exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and Exercise Sciences Liverpool John Moores UniversityLiverpool L33AFUK

background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public *** has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in English were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the Rob 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： Exercise Experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation

Inappropriate antibiotic dispensing and use:A public health threat in the Philippines

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Asian Pacific Journal of Tropical Medicine 2022年第8期15卷 341-342页

作者： Eric david b.Ornos Elgin Paul b.Quebral Jeremy A.Ceriales Ourlad Alzeus G.Tantengco College of Medicine University of the Philippines ManilaManilaPhilippines

A high rate of improper antibiotic dispensing was reported to patients with presumed viral infections even without a prescription from a physician in Vietnam[1]. Imprudent antibiotic dispensing and use were also observed in other countries, including the Philippines. A large number of patients experienced respiratory symptoms, such as cough and rhinorrhea during the COVID-19 pandemic, which exacerbated this problem with antibiotic use.

关键词： dis pens Vietnam

Metal-dielectric-metal plasmonic waveguide devices for manipulating light at the nanoscale

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Chinese Optics Letters 2009年第4期7卷 302-308页

作者： Georgios Veronis Zongfu Yu Sukru Ekin Kocaba david A. b. Miller Mark L. brongersma Shanhui Fan Department of Electrical and Computer Engineering and Center for Computation and Technology Louisiana State University Baton Rouge LA 70803 USA Ginzton LaSoratory Stanford University Stanford CA 94305 USA GeSalle LaSoratory of Advanced Materials Stanford University Stanford CA 94305 USA

We review some of the recent advances in the development of subwavelength plasmonic devices for manipulating light at the nanoseale, drawing examples from our own work in metal-dielectric-metal （MDM） plasmonic waveguide devices. We introduce bends, splitters, and mode converters for MDM waveguides with no additional loss. We also demonstrate that optical gain provides a mechanism for on/off switching in MDM plasmonic waveguides. Highly efficient compact couplers between dielectric waveguides and MDM waveguides are also introduced.

关键词： Metals Multiplexing Nanotechnology Optical waveguides Plasmons Waveguide components Waveguides

Predicting factors for the need of extracorporeal membrane oxygenation for suicide attempts by cardiac medication:a single-center cohort study

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World Journal of Emergency Medicine 2022年第4期13卷 283-289页

作者： david Vandroux Thomas Aujoulat bernard-Alex Gaüzère bérénice Puech bertrand Guihard Olivier Martinet Intensive Care Unit Félix Guyon HospitalUniversity Teaching Hospital of La Réunion97400 Saint DenisReunion IslandFrance Cardiosurgical Intensive Care Unit Dupuytren II HospitalUniversity Teaching Hospital of Limoges87042 LimogesFrance UMR 1094 Neuro-épidémiologie Tropicale University of Limoges87042 LimogesFrance Cardiovascular Anesthesia Department Félix Guyon HospitalUniversity Teaching Hospital of La Réunion97400 Saint DenisReunion IslandFrance Service d’Aide Médicale d’Urgence Félix Guyon HospitalUniversity Teaching Hospital of La Réunion97400 Saint DenisReunion IslandFrance

bACKGROUND:Severe poisoning due to the overdosing of cardiac drugs can lead to cardiovascular *** order to decrease the mortality rate,the most severe patients should be transferred as quickly as possible to an extracorporeal membrane oxygenation(ECMO)***,the predictive factors showing the need for venous-arterial ECMO(VA-ECMO)had never been ***:A retrospective,descriptive,and single-center cohort *** consecutive patients admitted in the largest ICU of Reunion Island(Indian Ocean)between January 2013 and September 2018 for beta-blockers(bb),calcium channel blockers(CCb),renin-angiotensin-aldosterone system blockers,digoxin or anti-arrythmic intentional poisonings were *** implementation was the primary ***:A total of 49 consecutive admissions were *** patients had ECMO,39 patients did not have *** patients in ECMO group died,while no patients in the conventional group *** most relevant ECMO-associated factors were pulse pressure and heart rate at first medical contact and pulse pressure,heart rate,arterial lactate concentration,liver enzymes and left ventricular ejection fraction(LVEF)at *** pulse pressure at first medical contact and LVEF were significant after logistic ***:A transfer to an ECMO center should be considered for a pulse pressure<35 mmHg at first medical contact or LVEF<20%on admission to ICU.

关键词： Extracorporeal membrane oxygenation Implementation Cardiac medication Overdose Predicting factor

Effect of glaucoma on identification of bottle cap color in ophthalmic medications

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International Journal of Ophthalmology(English edition) 2019年第1期12卷 169-171页

作者： Jonathan Paul Jon david Hammer Roozbeh Akhtari brede Skillings Daniel b.Moore Department of Ophthalmology University of Kentucky Northwell Health Department of Ophthalmology Krieger Eye Institute

A prospective, nonrandomized, observational trial of 60 glaucoma patients to correlate visual acuity and visual field with ability to distinguish bottle cap color of commonly used ophthalmic medications was conducted. A total of 103 eyes from 60 patients(30 women) were evaluated. The mean logMAR acuity was 0.34±0.54(approximately 20/45 Snellen acuity), average Humphrey Visual Field(HVF) mean deviation was-8.58±8.69 db, mean Ishihara plates(out of 14) were 11.78±4.15, and bottle cap color score(out of 10) was 8.56±2.51. Multiple linear regression analysis revealed an independent correlation of visual acuity(P=0.0137) and Ishihara score(Pbut no significant effect with visual field mean deviation(P>0.05). Glaucoma patients with poor visual acuity, but not necessarily advanced visual field loss, are likely to have difficultly identifying the color of their bottle caps. Physicians should be cognizant of this potential issue when reviewing medications with patients.

关键词： glaucoma color vision compliance medication patient communication

Microstructure and mechanical properties of Ti-6Al-4V-5% hydroxyapatite composite fabricated using electron beam powder bed fusion

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Journal of Materials Science & Technology 2019年第2期35卷 309-321页

作者： César A.Terrazas Lawrence E.Murr Diego bermudez Edel Arrieta david A.Roberson Ryan b.Wicker W.M.Keck Center for 3D Innovation The University of Texas at El PasoEl PasoTX 79968USA Department of Mechanical Engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

A novel, Ti-6 Al-4 V(Ti64)/Hydroxyapatite(HA at 5% by weight concentration) metal/ceramic composite has been fabricated using electron beam powder bed fusion(EPbF) additive manufacturing(AM): specifically, the commercial electron beam melting(EbM?) process. In addition to solid Ti64 and Ti64/5% HA samples, four different unit cell(model) open-cellular mesh structures for the Ti64/5% HA composite were fabricated having densities ranging from 0.68 to 1.12 g/cm^3, and corresponding Young's moduli ranging from 2.9 to 8.0 GPa, and compressive strengths ranging from ~3 to 11 MPa. The solid Ti64/5%HA composite exhibited an optimal tensile strength of 123 MPa, and elongation of 5.5% in contrast to a maximum compressive strength of 875 MPa. both the solid composite and mesh samples deformed primarily by brittle deformation, with the mesh samples exhibiting erratic, brittle crushing. Solid, EPbF-fabricated Ti64 samples had a Vickers microindentation hardness of 4.1 GPa while the Ti64/5%HA solid composite exhibited a Vickers microindentation hardness of 6.8 GPa. The lowest density Ti64/5%HA composite mesh strut sections had a Vickers microindentation hardness of 7.1 GPa. Optical metallography(OM) and scanning electron microscopy(SEM) analysis showed the HA dispersoids to be highly segregated along domain or grain boundaries, but homogeneously distributed along alpha(hcp) platelet boundaries within these domains in the Ti64 matrix for both the solid and mesh composites. The alpha platelet width varied from ~5 μm in the EPbF-fabricated Ti64 to ~1.1 m for the Ti64/5%HA mesh strut. The precursor HA powder diameter averaged 5 μm, in contrast to the dispersed HA particle diameters in the Ti64/5%HA composite which averaged 0.5 m. This work highlights the use of EPbF AM as a novel process for fabrication of a true composite structure, consisting of a Ti64 matrix and interspersed and exposed HA domains, which to the authors' knowledge has not been reported before. The results also illu

关键词： Hydroxyapatite (HA) Metal-matrix ceramic composites Open-cellular (mesh) structures Electron-beam powder bed fusion (EPbF) Additive manufacturing (AM) Mechanical properties Microstructure characterization

Proton-pump inhibitor use does not affect semen luality in subfertile men

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Asian Journal of Andrology 2018年第3期20卷 290-293页

作者： Sorena Keihani James R Craig Chong Zhang Angela P Presson Jeremy b.myers William O brant Kenneth I Aston benjamin R Emery Timothy G Jenkins Douglas T Carrell James M Hotaling Division of Urology Department of Surgery University of Utah Salt Lake City Utah 84132 USA Division of Epidemiology Department of Internal Medicine University of Utah Salt Lake City Utah 84132 USA Andrology and IVF Laboratory Department of Surgery (Urology) University of Utah Salt Lake City Utah 84108 USA

Proton-pump inhibitors （PPIs） are among the most widely used drugs worldwide. PPI use has recently been linked to adverse changes in semen quality in healthy men; however, the effects of PPI use on semen parameters remain largely unknown specifically in cases with male factor infertility. We examined whether PPI use was associated with detrimental effects on semen parameters in a large population of subfertile men. We retrospectively reviewed data from 12 257 subfertile men who had visited our fertility clinic from 2003 to 2013. Patients who reported using any PPIs for 〉3 months before semen sample collection were included; 7698 subfertile men taking no medication served as controls. Data were gathered on patient age, medication use, and conventional semen parameters; patients taking any known spermatotoxic medication were excluded. Linear mixed-effect regression models were used to test the effect of PPI use on semen parameters adjusting for age. A total of 248 patients （258 samples） used PPIs for at least 3 months before semen collection. In regression models, PPI use （either as the only medication or when used in combination with other nonspermatotoxic medications） was not associated with statistically significant changes in semen parameters. To our knowledge, this is the largest study to compare PPI use with semen parameters in subfertile men. Using PPIs was not associated with detrimental effects on semen quality in this retrospective study.

关键词： infertility proton-pump inhibitors semen analysis sperm quality spermatozoa