4,342 research outputs found

    Nondeterminstic ultrafast ground state cooling of a mechanical resonator

    Full text link
    We present an ultrafast feasible scheme for ground state cooling of a mechanical resonator via repeated random time-interval measurements on an auxiliary flux qubit. We find that the ground state cooling can be achieved with \emph{several} such measurements. The cooling efficiency hardly depends on the time-intervals between any two consecutive measurements. The scheme is also robust against environmental noises.Comment: 4 pages, 3 figure

    Analysis of nanoprobe penetration through a lipid bilayer

    Get PDF
    AbstractWith the rapid development of nanotechnology and biotechnology, nanoscale structures are increasingly used in cellular biology. However, the interface between artificial materials and a biological membrane is not well understood, and the harm caused by the interaction is poorly controlled. Here, we utilize the dissipative particle dynamics simulation method to study the interface when a nanoscale probe penetrates the cell membrane, and propose that an appropriate surface architecture can reduce the harm experienced by a cell membrane. The simulation shows that a hydrophilic probe generates a hydrophilic hole around the probe while a hydrophobic probe leads to a ‘T-junction’ state as some lipid molecules move toward the two ends of the probe. Both types of probe significantly disrupt lipid bilayer organization as reflected by the large variations in free energy associated with penetration of the membrane. Considering the hydrophilic/hydrophobic nature of the lipid bilayer, three other hydrophilic/hydrophobic patterns – band pattern, axial pattern and random pattern – are discussed to reduce the damage to the lipid membrane. Both the free energy analysis and simulation studies show that the axial pattern and the random pattern can both minimize the variations in free energy with correspondingly smaller adverse effects on membrane function. These results suggest that the axial pattern or random pattern nanoprobe generates a mild interaction with the biological membrane, which should be considered when designing nondestructive nanoscale structures

    Crowdsourcing to Improve HIV and Sexual Health Outcomes: a Scoping Review.

    Get PDF
    PURPOSE OF REVIEW: This review synthesizes evidence on the use of crowdsourcing to improve HIV/sexual health outcomes. RECENT FINDINGS: We identified 15 studies, including four completed randomized controlled trials (RCTs), one planned RCT, nine completed observational studies, and one planned observational study. Three of the four RCTs suggested that crowdsourcing is an effective, low-cost approach for improving HIV testing and condom use among key populations. Results from the observational studies revealed diverse applications of crowdsourcing to inform policy, research, and intervention development related to HIV/sexual health services. Crowdsourcing can be an effective tool for informing the design and implementation of HIV/sexual health interventions, spurring innovation in sexual health research, and increasing community engagement in sexual health campaigns. More research is needed to examine the feasibility, acceptability, and effectiveness of crowdsourcing interventions, particularly in low- and middle-income countries

    Social innovation in diagnostics: three case studies.

    Get PDF
    BACKGROUND: Diagnostics are essential for identifying and controlling diseases. However, limited access to diagnostics hinders public health efforts in many settings. Social innovation may provide a framework for expanding access to diagnostics in the global south. Here social innovation is defined as implementing a known public health tool via a novel, community-driven technique. MAIN BODY: In this article, we discuss three diverse cases that show the potential for using social innovation in diagnostics. The cases chosen for inclusion here demonstrate the importance of social innovation in diagnostics across different geographic, cultural, and health system contexts. They include malaria testing via schools in Malawi, cervical human papillomavirus (HPV) sample self-collection in Peru, and crowdsourcing human immunodeficiency virus (HIV) testing in China. For each case, we present the public health problem and the impact of using social innovation to increase accessibility of diagnostics. We discuss implications of each diagnostic approach and the importance of social innovation in creating these potential solutions. We argue that social innovation is useful in improving the delivery of essential diagnostic tools in low- and middle-income countries. CONCLUSIONS: Interventions in Malawi, Peru, and China suggest social innovation increases uptake of diagnostics. The same tools and principles utilized in these cases can be adapted for use in other contexts. Such diagnostic innovations may help improve identification of and linkage to care for many diseases. The approach presents a unique opportunity to better address public health issues and increase accessibility in LMIC health systems

    Expansion of specialized epidermis induced by hormonal state and mechanical strain

    Get PDF
    In mammals, some sites of specialized skin such as the palms, soles, and lips grow proportionally with the animal. However, other types of specialized skin such as the nipple and anal/genital region are dramatically altered with changes of reproductive status. The specific cell types that mediate the growth of these sites have not been identified. In the mouse, we observed a dramatic expansion of the specialized epidermis of the nipple, coupled to changes in connective tissue and hair shaft density, which we designate as areola formation. During this process thymidine analog uptake was elevated in the epidermis and hair follicles. Although there were no changes in connective tissue cell proliferation, we did observe an altered expression of extracellular matrix genes. In addition, the fibroblasts of the virgin nipple areola and region showed increased transcript and protein levels for estrogen, progesterone, relaxin, and oxytocin relative to those of ventral skin. To determine the role of pregnancy, lactation hormonal milieu, and localized mechanical strain on areola formation, we created models that separated these stimuli and evaluated changes in gross structure, proliferation and protein expression. While modest increases of epidermal proliferation and remodeling of connective tissue occurred as a result of individual stimuli, areola formation required exposure to pregnancy hormones, as well as mechanical strain

    Higgs particle detection using jets

    Full text link
    We study the possibility of detecting the Higgs boson in the intermediate mass range via its two jet channel. We consider only Higgs bosons produced in association with a ttˉt \bar{t} pair. Both tt and tˉ\bar{t} are required to decay semileptonically to reduce the QCD background. The signal is compared with the main background, ttˉ+2t \bar{t} + 2 jets, after appropriate cuts. A sizable signal above background is seen in our simulation at the parton level. Use of the ttˉZt\bar{t}Z channel with Z Z decaying to l+l−l^+ l^- is suggested for eliminating theoretical uncertainties in determining the ttˉHt \bar{t}H signal.Comment: 10 pages, Fig.1 a,b,c,d(surve on request), plain tex, PVAM-HEP-93-

    Impact of reactor configurations on the performance of a granular anaerobic membrane bioreactor for municipal wastewater treatment

    Full text link
    © 2017 Elsevier Ltd This study compared overall performance of an external granular anaerobic membrane bioreactor and a submerged granular anaerobic membrane bioreactor (EG-AnMBR and SG-AnMBR, respectively), to determine which type of G-AnMBRs is more preferred for municipal wastewater treatment. Both systems presented similar COD removal efficiencies (over 91%) and methane yield of 160 mL CH4 (STP) (g COD removed)−1 although volatile fatty acids (VFA) accumulation was found in the SG-AnMBR. Membrane direct incorporation into the SG-AnMBR significantly affected the concentration and properties of microbial products (e.g. soluble microbial products (SMP) and extracellular polymeric substances (EPS)) in the cake layer, mixed liquor and granular sludge, as well as granular sludge size and settleability. The EG-AnMBR demonstrated less SMP and EPS in the mixed liquor and cake layer, which might reduce the cake layer resistance and lower the fouling rate. Liquid chromatography-organic carbon detection (LC-OCD) analysis of foulant revealed that biopolymers along with low molecular weight neutrals and acids and building blocks were responsible for higher fouling propensity in the SG-AnMBR. It is evident that compared to the SG-AnMBR, the EG-AnMBR serves as a better G-AnMBR configuration for municipal wastewater treatment due to less fouling propensity and superior granule quality
    • …
    corecore