Orbital transfer vehicle oxygen turbopump technology. Volume 1: Design, fabrication, and hydrostatic bearing testing

The design, fabrication, and initial testing of a rocket engine turbopump (TPA) for the delivery of high pressure liquid oxygen using hot oxygen for the turbine drive fluid are described. This TPA is basic to the dual expander engine which uses both oxygen and hydrogen as working fluids. Separate tasks addressed the key issue of materials for this TPA. All materials selections emphasized compatibility with hot oxygen. The OX TPA design uses a two-stage centrifugal pump driven by a single-stage axial turbine on a common shaft. The design includes ports for three shaft displacement/speed sensors, various temperature measurements, and accelerometers

Critical points in strategies for the diagnosis and treatment of osteoporosis

Current treatment decisions for osteoporosis depend on the fracture risk calculated based on the results of comprehensive diagnostic procedures [clinical risk factors (CRF), densitometry (BMD), morphometry, and bone turnover markers (BTM)]. Recently developed fracture risk assessment tool (FRAXTM) represents an important new achievement as a 10-year fracture risk calculation based on femoral neck densitometry and age combined with independent clinical fracture risk factors. FRAXTM presents several options: FRAXTM BMI (body mass index) is advocated as a helpful screening tool to identify the group of patients with high fracture risk, independently of access to densitometry and FRAXTM, utilizing hip densitometry. In both cases, the probability of major fractures or hip fractures are calculated during performed diagnostic evaluations. Operating FRAXTM algorithm does not include spinal bone mineral density, which is its main limitation. With the aim of improvement of anti-fracture efficacy of therapeutic management of osteoporosis, we have extended our discussion to three integral elements of existent strategy: 1) screening outlines, 2) principles of drug selection, and 3) treatment benefit evaluation. Since osteoporosis is a chronic disease, long-term adherence to the treatment is important. The suitability of the drug, the patient’s preference, tolerability, and convenience should all be considered. Anti-catabolic drugs are most appropriate in patients with high bone turnover, while anabolic drugs demonstrate efficacy irrespective of bone turnover. BMD measurement is most widely used for long-term assessment of the efficacy of osteoporosis treatment. The measurements of bone turnover markers (BTMs) can be considered a useful shortterm (at 3 months) monitoring tool in selected patients. In both BTM and BMD, the least significant change (LSC) method should be used for interpretation of the results. Fractures are not a reliable clinical endpoint for evaluating the effectiveness of therapy in individual patients because of their stochastic nature. If fractures occur, however, the need for drug change and additional non-pharmacological treatment (fall prevention, balance training, muscle strengthening) should always be considered.Kryterium interwencji farmakoterapeutycznej w osteoporozie bez złamań stanowi ocena indywidualnego bezwzględnego 10-letniego ryzyka złamań, określonego na podstawie kompleksowej analizy czynników ryzyka złamań. Kompleksowa ocena ryzyka złamań w perspektywie 10-letniej integruje wyniki badań diagnostycznych (densytometria, ocena bezobjawowych złamań kręgów, ocena metabolizmu kostnego) oraz wybranych klinicznych czynników ryzyka złamań. Wprowadzony w 2008 roku kalkulator FRAXTM (WHO Fracture Risk Assessment Tool) pozwala na szybkie i proste obliczanie 10-letniego ryzyka złamań, które u indywidualnego pacjenta powinno być podstawą do podejmowania dalszych decyzji diagnostycznych i terapeutycznych. FRAXTM opracowany jako kalkulator obliczający 10-letnie ryzyko złamań może być stosowany z uwzględnieniem densytometrii bliższej nasady kości udowej wraz z innymi niezależnymi czynnikami ryzyka złamań. FRAXTM oparty na wskaźniku masy ciała (BMI, body mass index), gęstości mineralnej kości (BMI, bez uwzględnienia pomiaru BMD [bone mineral density]) może być przydatnym narzędziem przesiewowym dla lekarzy pierwszego kontaktu oceniających ryzyko złamań (case finding strategy), zwłaszcza w przypadku ograniczonego dostępu do densytometrii. W obu przypadkach FRAXTM może oceniać 10-letnie ryzyko złamania bliższej nasady kości udowej oraz wszystkich złamań osteoporotycznych. Głównym ograniczeniem algorytmu FRAXTM jest brak możliwości wykorzystania wyników badań densytometrycznych w lokalizacji kręgosłupa lędźwiowego. O ile decyzja, co do potrzeby leczenia farmakologicznego osteoporozy opiera się głównie na wielkości przewidywanego 10-letniego ryzyka złamania, to zasadniczymi kryteriami wyboru leku u indywidualnego pacjenta powinny być skuteczność przeciwzłamaniowa leku, oceniana w randomizowanych, kontrolowanych badaniach klinicznych, oraz potencjalne działania niepożądane, dostępność i łatwość stosowania. Na wybór leku wpływa także mechanizm jego działania: leki przeciwresorpcyjne są najbardziej skuteczne u chorych z zaawansowanym zanikiem kostnym i szybkim obrotem metabolicznym kości, podczas gdy leki anaboliczne lub podwójnym punkcie uchwytu (ranelinian strontu) działają niezależnie od wyjściowych wartości BMD czy aktywności obrotu kostnego. "Złotym standardem" leczenia osteoporozy pozostają bisfosfoniany. Ocena efektywności prowadzonej farmakoterapii jest jednym z ważniejszych elementów strategii w postępowaniu przeciwzłamaniowym. Pomiar BMD jest uznanym długoterminowym wskaźnikiem zastępczym oceny wytrzymałości mechanicznej kości. Wskaźnikiem krótkoterminowym oceny efektywności terapii (3 miesiące) jest pomiar poziomu markerów obrotu kostnego w surowicy. W obu przypadkach podstawowym kryterium interpretacyjnym powinna być najmniejsza znacząca zmiana (LSC, least significant change). Interpretacja znaczenia złamania kości w trakcie terapii antyzłamaniowej jest niejednoznaczna. Złamań nie należy interpretować jako bezwzględnego wskaźnika braku efektywności stosowanej farmakoterapii, należy jednak ponownie zanalizować dane pacjenta, wprowadzając zwłaszcza modyfikację postępowania niefarmakologicznego

CEP-stable Tunable THz-Emission Originating from Laser-Waveform-Controlled Sub-Cycle Plasma-Electron Bursts

We study THz-emission from a plasma driven by an incommensurate-frequency two-colour laser field. A semi-classical transient electron current model is derived from a fully quantum-mechanical description of the emission process in terms of sub-cycle field-ionization followed by continuum-continuum electron transitions. For the experiment, a CEP-locked laser and a near-degenerate optical parametric amplifier are used to produce two-colour pulses that consist of the fundamental and its near-half frequency. By choosing two incommensurate frequencies, the frequency of the CEP-stable THz-emission can be continuously tuned into the mid-IR range. This measured frequency dependence of the THz-emission is found to be consistent with the semi-classical transient electron current model, similar to the Brunel mechanism of harmonic generation

Mechanizmy działania leków antykatabolicznych stosowanych w osteoporozie

Bone remodeling is essential for skeletal and the whole body health. Imbalance in skeletal turnover, so that bone resorption exceeds bone formation, may lead to reduction in bone strength and increase fractures risk. The main target of anticatabolic therapy is to normalize increased osteoclasts activity and bone turnover. Molecular mechanisms of action of this class of drugs are related with different points in cellular signaling pathways that control osteoclasts differentiation and resorbing activity. These mechanisms are briefly described in our review.Procesy przebudowy tkanki kostnej leżą u podstawy prawidłowego funkcjonowania układu szkieletowego i całego organizmu. Zachwianie równowagi pomiędzy procesami kościotworzenia a resorpcją, na korzyść resorpcji kostnej, może prowadzić do obniżenia wytrzymałości mechanicznej kości i do złamań. Głównym celem działania leków antykatabolicznych jest normalizacja nadmiernej aktywności resorpcyjnej osteoklasta i podwyższonego obrotu kostnego. Molekularne mechanizmy działania leków z tej grupy wykorzystują różne punkty w sygnalizacji zewnątrz- i wewnątrzkomórkowej prowadzącej do różnicowania bądź aktywności resorpcyjnej osteoklastów. W niniejszej pracy krótko je opisano

Sex‑Specific Changes in Physical Performance Following Military Training: A Systematic Review

This is the final version of the article. Available from Springer Verlag via the DOI in this record.Introduction Men and women joining the military undergo the same training, often in mixed-sex platoons. Given the inherent physiological and physical performance differences between men and women, it is reasonable to question whether sex differences exist in the adaptation to military training and, therefore, whether sex-specific training should be employed to optimise training adaptations. Objective To systematically review the literature evaluating changes in the physical performance of men and women following military training. Methods Six database sources were searched in addition to extensive secondary searching. Primary prospective intervention studies (all designs) evaluating physical training interventions in military populations, reporting pre- to post-training changes in physical fitness outcomes for both women and men, were included. Results We screened 3966 unique records. Twenty-nine studies (n = 37 study reports) were included, most of which were conducted in the USA and evaluated initial training for military recruits. Positive changes were more consistently observed in aerobic fitness and muscle strength (whole body and upper body) outcomes than lower body strength, muscle power or muscle endurance outcomes, following physical training. Relative pre- to post-training changes for all outcome measures tended to be greater in women than men although few statistically significant sex by outcome/time interactions were observed. Conclusion Improvements in some, but not all, performance components were observed following a period of military training. Largely, these improvements were not significantly different between sexes. Further prospective research is needed to evaluate sex-specific differences in the response to physical training in controlled conditions to improve military physical training outcomes for both sexes.This work was commissioned through the Defence Human Capability Science and Technology Centre (DHCSTC, Grant number TIN 3.199). DHCSTC had no role in the design, analysis or writing of this article

What helps to support people affected by Adverse Childhood Experiences? A review of evidence

Adverse Childhood Experiences (ACEs) include physical, sexual or emotional abuse; neglect; domestic violence in the home; homelessness or living in care; parental mental health problems or substance abuse; and parents who are absent through imprisonment, separation or death. We sought to understand how people affected by ACEs can best be supported by conducting a review of evidence. The review involved three components: a qualitative synthesis of UK views studies; a systematic review of reviews which measured the effectiveness of interventions to support people affected by ACEs; and a stakeholder workshop with young people with lived experience of ACEs. The review was commissioned by the Department of Health and Social Care

Jakość badań densytometrycznych w Polsce : wyniki oceny wstępnej

Background: The quality of measurements is the main problem in clinical diagnostics. Only a well-designed and properly implemented quality control system ensures that real and precise measurement results are obtained. The aim of our study was to evaluate the quality of bone mineral density measurements in laboratories in Poland. Material/Methods: 15 laboratories from 9 cities participated in the study. The evaluation was performed on the basis of International Society for Clinical Densitometry recommendations and data from the literature. Part I of the evaluation comprised checking the calibration and stability of the densitometer, the safety of acquisition data, the documentation of services, and the reproducibility of measurements in patients. Part II comprised reproducibility, based on phantom testing, using European spine phantom and anthropomorphic spine phantom. Phantom measurements and analysis were done in a routine manner by native operators. Results: The only activity which was properly and regularly performed in all laboratories was calibration. The other activities were performed properly in less than half of the laboratories, and some of them only in single laboratories. In nearly half of the laboratories the reproducibility error exceeded the tolerance limit. Conclusions: The present study suggests that the quality of bone mineral density measurement in Poland is rather low. Introducing quality control in laboratories and training courses for operators is strongly recommended

New distribution data for two species of the Neotropical genus Lathecla Robbins, 2004 (Lepidoptera, Lycaenidae, Eumaeini)

Abstract. The species Lathecla carolyna Busby, 2015 described recently from Ecuador is reported to occur also in Venezuela and Colombia. An additional Peruvian occurrence of L. mimula (Draudt, 1920) is also documented