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Transonic Airfoil Design and Optimization for an Unmanned Air Vehicle Concept 被引量:1
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作者 Kasim Biber Trenton White 《Journal of Mechanics Engineering and Automation》 2019年第6期193-202,共10页
Design,optimization and analysis of a new energy efficient 16%thick transonic airfoil were completed for a notional air vehicle concept.The airfoil specifications included a range of Reynolds number per foot from 1.7 ... Design,optimization and analysis of a new energy efficient 16%thick transonic airfoil were completed for a notional air vehicle concept.The airfoil specifications included a range of Reynolds number per foot from 1.7 million to 2.5 million and Mach number from 0.4 to 0.8.Shape optimization in geometry and inverse design modules of the airfoil analysis program MSES were used to design a new 16%thick reference airfoil.The performance of the reference airfoil was then optimized with an objective of minimizing drag coefficient for 7 design points with conflicting requirements in Reynolds and Mach number by using the MSES/LINDOP optimizer.The optimization results in an upward shift of drag bucket in the direction of higher lift coefficient.Both surface pressure distribution and Mach contour plots show that supersonic compression waves on airfoil surface are terminated at Mach 0.78 with a normal shock wave and associated flow separation,which causes not only a decrease of the maximum suction pressure,but also a decrease in lift and increase in drag coefficient.The new optimized airfoil shows robust performance when operating within the specified design constraints. 展开更多
关键词 AIRFOIL optimization AIRFOIL design TRANSONIC AIRFOILS shock FLOWS compression waves.
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Success Rate of Dental Implants Placed in the Atrophic Posterior Maxilla with Intentional Sinus Floor Perforation in Lieu of Indirect Sinus Augmentation: A Retrospective Report of 26 Consecutive Patients and Literature Review
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作者 Khurram M.Shahzad Andrew Q.Madson +1 位作者 Evan M.Shipp Andrew W.Ellis 《Open Journal of Stomatology》 2017年第2期113-120,共8页
Purpose: To assess surgical success rate of placing dental implants in the atrophic posterior maxilla engaging the maxillary sinus floor in patients with inadequate posterior maxillary alveolar bone height (PMABH). Me... Purpose: To assess surgical success rate of placing dental implants in the atrophic posterior maxilla engaging the maxillary sinus floor in patients with inadequate posterior maxillary alveolar bone height (PMABH). Methods: 26 patients with PMABH of 7 - 10 mm had 39 implants placed between July 2012 and June 2014. These implants were placed protruding apically 1 - 3 mm into the maxillary sinus engaging the sinus floor. At stage one, implants and cover screws were placed, followed by stage two, 5 - 6 months later. The implants were considered osseo-integrated in the absence of symptoms, mobility and inflammation. Periapical radiographs were taken to rule out peri-implant radiolucency. Restorative treatment was completed 2 months thereafter. Patients were scheduled to have a dental exam (6 - 12 months after delivery of prosthesis) and the implants were evaluated clinically and radiographically. A retrospective review was conducted to assess the surgical success rate of this treatment modality. Clinic charts, radiographs and digital implant log were reviewed for all patients with PMABH of 7 - 10 mm who received dental implants in the posterior maxilla to determine the success rate of this treatment modality. Results: 26 patients who had 39 implants placed were included in the study. All implants (100%) were osseo-integrated at the time of uncovering (stage 2). None of the implants (0%) had mobility or inflammation around them. Stage 2 was successfully performed on all 39 implants (100%). All implants (100%) in these patients had been restored, and were in good condition without mobility or inflammation, and had been functioning well 6 - 12 months after restoration. Conclusion: This study suggests that a high success rate can be attained placing dental implants in the posterior maxilla while perforating and engaging the cortical maxillary sinus floor. A future prospective study that compares this technique with the internal sinus lift would likely help elucidate this suggestion. 展开更多
关键词 POSTERIOR MAXILLA Implants SINUS PERFORATION
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Impact of prehospital medical evacuation (MEDEVAC) transport time on combat mortality in patients with noncompressible torso injury and traumatic amputations: a retrospective study
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作者 Joseph K.Maddry Crystal A.Perez +3 位作者 Alejandra G.Mora Jill D.Lear Shelia C.Savell Vikhyat S.Bebarta 《Military Medical Research》 SCIE CAS CSCD 2019年第1期23-30,共8页
Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality... Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality. Limited data exist on the influence of transport time on patient outcomes with specific injury types. The objective of this study was to determine the impact of the duration of time from the initial request for medical evacuation to arrival at a medical treatment facility on morbidity and mortality in casualties with traumatic extremity amputation and noncompressible torso injury(NCTI).Methods: We completed a retrospective review of MEDEVAC patient care records for United States military personnel who sustained traumatic amputations and NCTI during Operation Enduring Freedom between January 2011 and March 2014. We grouped patients as traumatic amputation and NCTI(AMP+NCTI), traumatic amputation only(AMP),and neither AMP nor NCTI(Non-AMP/NCTI). Analysis was performed using chi-squared tests, Fisher's exact tests,Cochran-Armitage Trend tests, Shapiro-Wilks tests, Wilcoxon and Kruskal-Wallis techniques and Cox proportional hazards regression modeling.Results: We reviewed 1267 records, of which 669 had an injury severity score(ISS) of 10 or greater and were included in the analysis. In the study population, 15.5% sustained only amputation injuries(n=104, AMP only), 10.8% sustained amputation and NCTI(n=72, AMP+NCTI), and 73.7% did not sustain either an amputation or an NCTI(n=493,Non-AMP/NCTI). AMP+NCTI had the highest mortality(16.7%) with transport time greater than 60 min. While the AMP+NCTI group had decreasing survival with longer transport times, AMP and Non-AMP/NCTI did not exhibit the same trend.Conclusions: A decreased transport time from the point of injury to a medical treatment facility was associated with decreased mortality in patients who suffered a combination of amputation injury and NCTI. No significant association between transport time and outcomes was found in patients who did not sustain NCTI. Priority for rapid evacuation of combat casualties should be given to those with NCTI. 展开更多
关键词 TRANSPORT TIME Non-compressible TORSO INJURY Traumatic amputation COMBAT
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采用三进制脉冲压缩序列的扩谱雷达波形设计
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作者 LEMIEUX Jerome A INGELS Franklin M 吴敖大 《现代雷达》 CSCD 1990年第3期49-54,48,共7页
脉冲压缩可用来提高发射功率的利用率,并使雷达信号增加同有的电子抗干扰(ECCM)能力。本文研究周期基带相关条件下具有理想副瓣响应的某类三进制序列。利用离散雷达模糊函数来计算周期和非周期调相三进制脉冲压缩序列两者的匹配滤波器... 脉冲压缩可用来提高发射功率的利用率,并使雷达信号增加同有的电子抗干扰(ECCM)能力。本文研究周期基带相关条件下具有理想副瓣响应的某类三进制序列。利用离散雷达模糊函数来计算周期和非周期调相三进制脉冲压缩序列两者的匹配滤波器响应。列出了三进制脉冲压缩序列、二进制最长序列和弗兰克多相码根据离散模糊函数计算出的数值表,并对它们作了比较,以便说明三进制序列是脉冲压缩雷达的一种极好选择方案。 展开更多
关键词 脉冲压缩雷达 扩谱雷达 波形设计
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A 30% incidence of renal cysts with varying sizes and densities in biomedical research swine is not associated with renal dysfunction
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作者 Belinda I.Gómez Joshua S.Little +2 位作者 Alisa J.Leon Ian J.Stewart David M.Burmeister 《Animal Models and Experimental Medicine》 CSCD 2020年第3期273-281,共9页
Background:Renal cystic disease arising from various etiologies results in fluid-filled cavities within the kidneys.Moreover,preexisting renal dysfunction has been shown to exacerbate multiple pathologies.While swine ... Background:Renal cystic disease arising from various etiologies results in fluid-filled cavities within the kidneys.Moreover,preexisting renal dysfunction has been shown to exacerbate multiple pathologies.While swine bred for biomedical research are often clinically inspected for illness/parasites,more advanced diagnostics may aid in uncovering underlying renal abnormalities.Methods:Computed tomography was performed in 54 female prepubertal Yorkshire swine to characterize renal cysts;urine and blood chemistry,and histology of cysts were also performed.Results:Digital reconstruction of right and left kidneys demonstrated that roughly one-third of the animals(17/54;31%)had one or more renal cyst.Circulating biomarkers of renal function were not different between animals that had cysts and those that did not.Alternatively,urinary glucose(P=.03)was higher and sodium(P=.07)tended to be lower in animals with cysts compared to animals without,with no differences in protein(P=.14)or potassium(P=.20).Aspiration of cystic fluid was feasible in two animals,which revealed that the cystic fluid urea nitrogen(97.6±28.7 vs 911.3±468.2 mg/dL),potassium(29.8±14.4 vs 148.2±24.85 mmol/L),uric acid(2.55±1.35 vs 11.4±5.65 mg/dL),and creatinine(60.34±17.26 vs 268.99±95.79 mg/dL)were much lower than in the urine.Histology demonstrated a cyst that markedly compresses the adjacent cortex and is lined by a single layer of flattened epithelium,bounded by fibrous connective tissue which extends into the parenchyma.There is tubular atrophy and loss in these areas.Conclusion:This study provides valuable insight for future studies focusing on kidney function in swine bred for biomedical research. 展开更多
关键词 computed tomography CYST KIDNEY renal dysfunction SWINE
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Silk fibroin as an additive for cell-free protein synthesis 被引量:1
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作者 Marilyn S.Lee Chia-Suei Hung +3 位作者 Daniel A.Phillips Chelsea C.Buck Maneesh K.Gupta Matthew W.Lux 《Synthetic and Systems Biotechnology》 SCIE 2020年第3期145-154,共10页
Cell-free systems contain many proteins and metabolites required for complex functions such as transcription and translation or multi-step metabolic conversions.Research into expanding the delivery of these systems by... Cell-free systems contain many proteins and metabolites required for complex functions such as transcription and translation or multi-step metabolic conversions.Research into expanding the delivery of these systems by drying or by embedding into other materials is enabling new applications in sensing,point-of-need manufacturing,and responsive materials.Meanwhile,silk fibroin from the silk worm,Bombyx mori,has received attention as a protective additive for dried enzyme formulations and as a material to build biocompatible hydrogels for controlled localization or delivery of biomolecular cargoes.In this work,we explore the effects of silk fibroin as an additive in cell-free protein synthesis(CFPS)reactions.Impacts of silk fibroin on CFPS activity and stability after drying,as well as the potential for incorporation of CFPS into hydrogels of crosslinked silk fibroin are assessed.We find that simple addition of silk fibroin increased productivity of the CFPS reactions by up to 42%,which we attribute to macromolecular crowding effects.However,we did not find evidence that silk fibroin provides a protective effects after drying as previously described for purified enzymes.Further,the enzymatic crosslinking transformations of silk fibroin typically used to form hydrogels are inhibited in the presence of the CFPS reaction mixture.Crosslinking attempts did not impact CFPS activity,but did yield localized protein aggregates rather than a hydrogel.We discuss the mechanisms at play in these results and how the silk fibroin-CFPS system might be improved for the design of cell-free devices. 展开更多
关键词 Cell-free systems Cell-free protein synthesis CFPS Silk fibroin PRESERVATION
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Comparison of magnetic properties of DNA-cetyltrimethyl ammonium complex with those of natural DNA
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作者 KWON Young-Wan CHOI Dong Hoon +3 位作者 JIN Jung-Il LEE Chang Hoon KOH Eui Kwan GROTE James G. 《Science China Chemistry》 SCIE EI CAS 2012年第5期814-821,共8页
We prepared the DNA-cetyltrimethyl ammonium complex, as well as the same complex intercalated with stable organic free radicals, and studied their magnetic properties by electron magnetic resonance (EMR) spectroscopy ... We prepared the DNA-cetyltrimethyl ammonium complex, as well as the same complex intercalated with stable organic free radicals, and studied their magnetic properties by electron magnetic resonance (EMR) spectroscopy and by measuring the magnetization on a superconducting quantum interference device (SQUID). The UV-vis and CD spectra of DNA-quaternary alkyl ammonium complex (DNA--Q+) in organic solvent clearly demonstrated that it retained the double helical B-form conformation. The interhelical spacing of double strand DNA (dsDNA) increased when the counter ions (Na+) of phosphate groups of the natural DNA were replaced with the long alkyl quaternary ammonium groups. The inter-helical distance of DNA-cetyltrimethyl ammonium (CTMA) was 39.1 as confirmed by X-ray diffractometry. In general, the magnetization of the DNA-CTMA complex solid was found to be significantly lower than that of natural DNA. Moreover, intercalation of the complex with stable organic free radicals did not improve magnetization, which again was in marked contrast to natural DNA. EMR spectroscopic behavior of the complex in the solid state also was quite different from that of natural DNA: The unique broad EMR signal of natural DNA in the low field region with g-value greater than 10 disappeared in the DNA-CTMA complex. 展开更多
关键词 natural DNA DNA-CTMA DNA-CTMA-PTMI magnetic property electron magnetic resonance (EMR) superconducting quantum interference device (SQUID)
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