3,484 research outputs found
Underwater space suit pressure control regulator
A device is reported for regulating the pneumatic pressure in a ventilated space suit relative to the pressure imposed on the suit when being worn by a person underwater to simulate space environment for testing and experimentation. A box unit located on the chest area of the suit comprises connections for suit air supply and return lines and carries a regulator valve that stabilizes the air pressure differential between the inside and outside of the suit. The valve and suit pressure is controlled by the suit occupant and the valve includes a mechanism for quickly dumping the suit pressure in case of emergency. Pressure monitoring and relief devices are also included in the box unit
The effective mass of two--dimensional 3He
We use structural information from diffusion Monte Carlo calculations for
two--dimensional 3He to calculate the effective mass. Static effective
interactions are constructed from the density-- and spin structure functions
using sumrules. We find that both spin-- and density-- fluctuations contribute
about equally to the effective mass. Our results show, in agreement with recent
experiments, a flattening of the single--particle self--energy with increasing
density, which eventually leads to a divergent effective mass.Comment: 4 pages, accepted in PR
Attractant Pheromone of the Neotropical Species Neomegalotomus parvus (Westwood) (Heteroptera: Alydidae).
The Neotropical broad-headed bug, Neomegalotomus parvus (Westwood), is adapted to various leguminous crops and is considered a pest in common bean and soybean. The chemical communication of this species was studied in order to identify an attractant pheromone. Males and females of N. parvus produce several short-chain esters and acids, and their antennae showed electrophysiological responses to ?ve of these compounds, three common to both sexes (hexyl butanoate, 4-methylhexyl butanoate, and hexyl hexanoate), and two female-speci?c compounds (4-methylhexyl pentanoate and hexyl pentanoate). Both aeration extracts of females and a solution containing ?ve synthetic compounds mimicking the natural blend were attractive to males and females N. parvus in a laboratory bioassay. Aspects of the chemical ecology of the broad-headed bugs and the possibility to use pheromone-baited traps in the ?eld for monitoring are discussed
Volatile Chemicals of Adults and Nymphs of the Eucalyptus
Thaumastocoris peregrinus is an introduced “true bug” that is now a severe pest in Eucalyptus plantations of various Southern Hemisphere countries. The semiochemicals of thaumastocorids are completely unknown. Therefore, volatile chemicals from T. peregrinus nymphs and adults were identified as possible leads for pheromones potentially useful for control. The contents of nymphal exocrine glands, which are shed at molting, were identified from extracts of exuviae. Adults lack functional metathoracic scent glands that are characteristic of most heteropterans; however, both males and females possess a glandular-appearing hold-fast organ that they quickly extrude posteriorly when disturbed. Whole body hexane extracts from males and females were prepared by freezing the insects in a flask so that they extruded the hold-fast organ, and then they were extracted with hexane. Volatiles from nymphal exuviae included benzaldehyde, octanol, (E)-2-octenol, octanoic acid, decanal, and hexanoic acid. Adult volatiles included 3-methylbut-2-en-1-yl butyrate and 3-methylbut-3-en-1-yl butyrate
Vaccines and Immunotherapeutics for the Treatment of Malignant Disease
The employment of the immune system to treat malignant disease represents an active area of biomedical research. The specificity of the immune response and potential for establishing long-term tumor immunity compels researchers to continue investigations into immunotherapeutic approaches for cancer. A number of immunotherapeutic strategies have arisen for the treatment of malignant disease, including various vaccination schemes, cytokine therapy, adoptive cellular therapy, and monoclonal antibody therapy. This paper describes each of these strategies and discusses some of the associated successes and limitations. Emphasis is placed on the integration of techniques to promote optimal scenarios for eliminating cancer
Plasma Cytokines/Chemokines as Predictive Biomarkers For Lymphedema in Breast Cancer Patients
Breast cancer-related lymphedema (BCRL) occurs in ~ 40% of patients after axillary lymph node dissection (ALND), radiation therapy (RT), or chemotherapy. First-line palliative treatment utilizes compression garments and specialized massage. Reparative microsurgeries have emerged as a second-line treatment, yet both compression and surgical therapy are most effective at early stages of LE development. Identifying patients at the highest risk for BCRL would allow earlier, more effective treatment. Perometric arm volume measurements, near-infrared fluorescent lymphatic imaging (NIRF-LI) data, and blood were collected between 2016 and 2021 for 40 study subjects undergoing treatment for breast cancer. Plasma samples were evaluated using MILLIPLEX human cytokine/chemokine panels at pre-ALND and at 12 months post-RT. A Mann-Whitne
A Paradigmatic Analysis of Digital Application Marketplaces
This paper offers a paradigmatic analysis of digital application marketplaces for advancing information systems (IS) research on digital platforms and ecosystems. We refer to the notion of digital application marketplace, colloquially called “appstores,” as a platform component that offers a venue for exchanging applications between developers and end-users belonging to a single or multiple ecosystems. Such marketplaces exhibit diversity in features and assumptions, and we propose that examining this diversity, and its ideal types, will help us to further understand the relationship between application marketplaces, platforms, and platform ecosystems. To this end, we generate a typology that distinguishes four kinds of digital application marketplaces: closed, censored, focused, and open marketplaces. The paper also offers implications for actors wishing to make informed decisions about their relationship to a particular digital application marketplace
Sustaining entrepreneurial business: a complexity perspective on processes that produce emergent practice
This article examines the management practices in an entrepreneurial small firm which sustain the business. Using a longitudinal qualitative case study, four general processes are identified (experimentation, reflexivity, organising and sensing), that together provide a mechanism to sustain the enterprise. The analysis draws on concepts from entrepreneurship and complexity science. We suggest that an entrepreneur’s awareness of the role of these parallel processes will facilitate their approaches to sustaining and developing enterprises. We also suggest that these processes operate in parallel at multiple levels, including the self, the business and inter-firm networks. This finding contributes to a general theory of entrepreneurship. A number of areas for further research are discussed arising from this result
- …