High-pressure calorimeter chamber tests for liquid oxygen/kerosene (LOX/RP-1) rocket combustion

An experimental program was conducted to investigate the rocket combustion and heat transfer characteristics of liquid oxygen/kerosene (LOX/RP-1) mixtures at high chamber pressures. Two water-cooled calorimeter chambers of different combustion lengths were tested using 37- and 61-element oxidizer-fuel-oxidizer triplet injectors. The tests were conducted at nominal chamber pressures of 4.1, 8.3, and 13.8 MPa abs (600, 1200, and 2000 psia). Heat flux Q/A data were obtained for the entire calorimeter length for oxygen/fuel mixture ratios of 1.8 to 3.3. Test data at 4.1 MPa abs compared favorably with previous test data from another source. Using an injector with a fuel-rich outer zone reduced the throat heat flux by 47 percent with only a 4.5 percent reduction in the characteristic exhaust velocity efficiency C* sub eff. The throat heat transfer coefficient was reduced approximately 40 percent because of carbon deposits on the chamber wall

Space station full-scale docking/berthing mechanisms development

One of the most critical operational functions for the space station is the orbital docking between the station and the STS orbiter. The program to design, fabricate, and test docking/berthing mechanisms for the space station is described. The design reflects space station overall requirements and consists of two mating docking mechanism halves. One half is designed for use on the shuttle orbiter and incorporates capture and energy attenuation systems using computer controlled electromechanical actuators and/or attenuators. The mating half incorporates a flexible feature to allow two degrees of freedom at the module-to-module interface of the space station pressurized habitat volumes. The design concepts developed for the prototype units may be used for the first space station flight hardware

Duverger, semi-presidentialism and the supposed French archetype

The concept of semi-presidentialism was first operationalised by Maurice Duverger. There are now 17 countries with semi-presidential constitutions in Europe. Within this set of countries France is usually considered to be the archetypal example of semi-presidentialism. This article maps the main institutional and political features of European semi-presidentialism on the basis of Duverger’s original three-fold schema. The most striking feature is the diversity of practice within this set of countries. This means that semi-presidentialism should not be operationalised as a discrete explanatory variable. However, there are ways of systematically capturing the variation within semi-presidentialism to allow cross-national comparisons. This diversity also means that France should not be considered as the archetypal semi-presidential country. At best, France is an archetypal example of a particular type of semi-presidentialism. Overall, Duverger’s main contribution to the study of semi-presidentialism was the original identification of the concept and his implicit insight that there are different types of semi-presidentialism. In the future, the study of semi-presidentialism would benefit from the development of theory-driven comparative work that avoids a reliance on France as the supposed semi-presidential archetype

Etiology of the Protein-Energy Wasting Syndrome in Chronic Kidney Disease: A Consensus Statement From the International Society of Renal Nutrition andMetabolism (ISRNM)

Protein-energy wasting (PEW), a term proposed by the International Society of Renal Nutrition and Metabolism (ISRNM), refers to the multiple nutritional and catabolic alterations that occur in chronic kidney disease (CKD) and associate with morbidity and mortality. To increase awareness, identify research needs, and provide the basis for future work to understand therapies and consequences of PEW, ISRNM provides this consensus statement of current knowledge on the etiology of PEW syndrome in CKD. Although insufficient food intake (true undernutrition) due to poor appetite and dietary restrictions contribute, other highly prevalent factors are required for the full syndrome to develop. These include uremia-induced alterations such as increased energy expenditure, persistent inflammation, acidosis, and multiple endocrine disorders that render a state of hypermetabolism leading to excess catabolism of muscle and fat. in addition, comorbid conditions associated with CKD, poor physical activity, frailty, and the dialysis procedure per se further contribute to PEW. Published by Elsevier Inc. on behalf of the National Kidney Foundation, Inc.Abbott NutritionShireAbbot Renal NutritionBaxter HealthcareKarolinska Inst, Div Renal Med, Dept Clin Sci Intervent & Technol, Solna, SwedenUniversidade Federal de São Paulo, Div Nephrol, Dept Med, São Paulo, BrazilVanderbilt Univ, Sch Med, Dept Med, Div Nephrol, Nashville, TN 37212 USAUniv Calif Irvine, Med Ctr, Harold Simmons Ctr, Div Nephrol & Hypertens, Orange, CA USAUniv Calif Davis, Dept Internal Med, Davis, CA 95616 USAUniv Calif Davis, Dept Biochem & Mol Med, Davis, CA 95616 USABaylor Coll Med, Dept Med, Div Nephrol, Houston, TX 77030 USAEmory Univ, Sch Med, Div Renal, Dept Med, Atlanta, GA 30306 USAAtlanta Dept Vet Affairs Med Ctr, Res Serv, Decatur, GA 30033 USAUniv Wurzburg, Div Nephrol, Dept Internal Med, D-97070 Wurzburg, GermanyUniv Hong Kong, Dept Med, Queen Mary Hosp, Hong Kong, Hong Kong, Peoples R ChinaVrije Univ Amsterdam Med Ctr, Dept Nephrol, Amsterdam, NetherlandsUniversidade Federal de São Paulo, Div Nephrol, Dept Med, São Paulo, BrazilWeb of Scienc

Introducing the national COPD resources and outcomes project

<p>Abstract</p> <p>Background</p> <p>We report baseline data on the organisation of COPD care in UK NHS hospitals participating in the National COPD Resources and Outcomes Project (NCROP).</p> <p>Methods</p> <p>We undertook an initial survey of participating hospitals in 2007, looking at organisation and performance indicators in relation to general aspects of care, provision of non-invasive ventilation (NIV), pulmonary rehabilitation, early discharge schemes, and oxygen. We compare, where possible, against the national 2003 audit.</p> <p>Results</p> <p>100 hospitals participated. These were typically larger sized Units. Many aspects of COPD care had improved since 2003. Areas for further improvement include organisation of acute care, staff training, end-of-life care, organisation of oxygen services and continuation of pulmonary rehabilitation.</p> <p>Conclusion</p> <p>Key Points: positive change occurs over time and repeated audit seems to deliver some improvement in services. It is necessary to assess interventions such as the Peer Review used in the NCROP to achieve more comprehensive and rapid change.</p

Uterotonic agents for preventing postpartum haemorrhage:a network meta-analysis (Protocol)

Brathys e Trigynobrathys (88 e 59 representantes, respectivamente) são as duas maiores seções do gênero Hypericum que são distribuídos principalmente na América Central e América do Sul. Das mais de 100 espécies sul-americanas de Hypericum quase 65 são endêmicas dos Páramos, ecossistemas de alta altitude, caracterizados por uma vegetação composta principalmente de plantas de roseta gigantes, arbustos e gramíneas, nos quais Hypericum é um componente importante. Tendo em vista o escasso conhecimento da fitoquímica destas espécies de Hypericum, o presente estudo teve como objetivo estudar a composição fitoquímica e algumas bioatividades de seis espécies de Hypericum nativas do Peru (H. aciculare, H. andinum, H. brevistylum, H. decandrum, H. laricifolium e H. silenoides). O material vegetal, seco ao ar, das seis espécies (partes aéreas, caules, folhas e flores), e material vegetal subterrâneo de H. andinum (raízes e caules), foram moídas e extraídas por maceração à temperatura ambiente com n-hexano. Além disso, foram obtidos extrato etanólicos a partir de quatro espécies (H. andinum, H. brevistylum, H. laricifolium e H. silenoides). Os extratos n-hexano foram fracionados e as frações foram sometidas a processos cromatográficos obtendo-se cinco derivados de floroglucinol diméricos conhecidos, uliginosina A, uliginosina B, isouliginosina B, hiperbrasilol B e isohiperbrasilol B. Além disso, foram identificadas duas estruturas monoméricas e duas diméricas inéditas em H. andinum (raízes) e em H. laricifolium, andinina A, hiperlaricifolina A, laricifolina A e laricifolina B. Andinina A mostrou potencial atividade antidepressiva no teste de natação forçada. Do mesmo modo, a atividade antidepressiva dos extratos etanólicos foi avaliada. Estes quatro extratos apresentaram potencial atividade antidepressiva. As análises fitoquímicas por TLC, HPLC-DAD e UPLC-DAD/Q-TOF-MS revelaram que estes extratos são ricos em flavonoides, principalmente hiperosídeo. Os extratos n-hexano foram também analisados por um novo método de HPLC-DAD associado a LC-MS e UPLC-Q-TOF-MS . A presença de homólogos superiores M + 14 e regioisómeros foi determinada. A ocorrência natural destes cinco floroglucinois homólogos superiores M + 14 é descrita e a presença de outros compostos identificados pelo padrão de fragmentação MS é apresentada. Estes extratos e o seu principal componente foram capazes de inibir potencialmente a quimiotaxia induzida por LPS. Estes resultados sugerem que os extratos de espécies de Hypericum das seções Brathys e Trigynobrathys são fontes potenciais de novos anti-inflamatórios e antidepressivos.Brathys and Trigynobrathys (88 and 59 representatives, respectively) are the two largest sections of the genus Hypericum that are principally distributed in Central and South America. Of the more than 100 South American species of Hypericum almost 65 are endemic to the Páramos, high-altitude grassland ecosystems characterized by vegetation composed mainly of giant rosette plants, shrubs and grasses, in which Hypericum is a prominent component. In view of the scare knowledge on the phytochemistry of these Hypericum species, the present research aimed to study the phytochemical composition and some bioactivities of six Peruvian Hypericum species (H. aciculare, H. andinum, H. brevistylum, H. decandrum, H. laricifolium and H. silenoides). The air-dried aerial plant material of those six species (stems, leaves and flowers), and underground plant material of H. andinum (roots and stems), were ground and extracted by maceration at room temperature with n-hexane. Additionally crude ethanolic extracts were obtained from four species (H. andinum, H. brevistylum, H. laricifolium and H. silenoides). The n-hexane extracts were fractionated, and fractions were further processed by chromatographic procedures to yield five known dimeric acylphloroglucinol derivatives uliginosin A, uliginosin B, isouliginosin B, hyperbrasilol B and isohyperbrasilol B. In addition, two monomeric and two dimeric acylphloroglucinol structures were identified in H. andinum (roots extract) and H. laricifolium for the first time, andinin A, hyperlaricifolin A, laricifolin A and laricifolin B. Andinin A showed potential antidepressant-like activity in the forced swimming test. Similarly, the antidepressant-like activity of the crude ethanolic extracts was assessed. These four extracts possessed a potential antidepressant-like activity. The phytochemical analyses by TLC, HPLC-DAD and UPLCDAD/Q-TOF-MS revealed that the extracts were rich in flavonoids, principally hyperoside. The n-hexane extracts were also analyzed by a new HPLC-DAD fingerprint method associated with LC-MS and UPLC-Q-TOF-MS. The presence of M + 14 higher homologues and regioisomers could be distinguished. The natural occurrence of these five M + 14 higher homologues is described and the presence of other compounds identified by their MS fragmentation pattern is presented. These extracts and their main dimeric acylphloroglucinol component were able to potently inhibit the LPS-induced chemotaxis on rat PMN. These results suggest that extracts of Hypericum species from sections Brathys and Trigynobrathys are potential sources of new anti-inflammatory and antidepressant molecules

CD33 Alzheimer’s disease locus: Altered monocyte function and amyloid biology

In our functional dissection of the CD33 Alzheimer’s disease susceptibility locus, we find that the rs3865444C risk allele is associated with greater cell surface expression of CD33 in monocytes (t50 = 10.06, pjoint=1.3×10–13) of young and older individuals. It is also associated with (1) diminished internalization of Aβ42) (2) accumulation of neuritic amyloid pathology and fibrillar amyloid on in vivo imaging and (3), increased numbers of activated human microglia