5,367 research outputs found

    On the Experimental Estimation of Surface Enhanced Raman Scattering (SERS) Cross Sections by Vibrational Pumping

    Get PDF
    We present an in-depth analysis of the experimental estimation of cross sections in Surface Enhanced Raman Scattering (SERS) by vibrational pumping. The paper highlights the advantages and disadvantages of the technique, pinpoints the main aspects and limitations, and provides the underlying physical concepts to interpret the experimental results. Examples for several commonly used SERS probes are given, and a discussion on future possible developments is also presented.Comment: To be submitted to J. Phys. Chem.

    Knowledge, attitudes, and practices of community pharmacists toward the management of acne vulgaris in Palestine: a cross-sectional study

    Get PDF
    Background Acne vulgaris (AV) is a common dermatological disease affecting almost 85% of teenagers. Patients with AV usually present at community pharmacies during the early stages of their disease. Aim The aim of this study was to assess community pharmacists’ knowledge, attitudes, and practice toward AV management in West Bank in Palestine. Methods This study was a cross-sectional questionnaire-based study. The questionnaire included four sections: 1) demographic, 2) knowledge, 3) attitude and practice items related causes, and 4) treatment options and counseling during management of patients with AV. A convenience sampling method was implemented in this study. Parametric and non-parametric tests were used to compare different issues as appropriate. P < 0.05 were considered significant. Result A total of 270 community pharmacists were interviewed, and more than half (54.1%) were males. The study revealed that community pharmacists had an inadequate level of knowledge on management of AV; only 7.7% had high levels of knowledge. Pharmacists have positive attitude regarding AV management, but inadequate knowledge was reflected on their treatment practices; only 10% of participants independently dealt with AV without referral. Pharmacists with a low level of knowledge showed five times more referrals than those with a high level of knowledge (OR: 5.3; P < 0.001), and those with a bachelor degree showed three times more referrals than postgraduates (OR: 3.3; P < 0.001). Conclusion There is a demand to update dermatological knowledge of community pharmacists and encourage them to attend structured training programs about the management of AV.Funding source: None

    Two-component model of the interaction of an interstellar cloud with surrounding hot plasma

    Full text link
    We present a two-component gasdynamic model of an interstellar cloud embedded in a hot plasma. It is assumed that the cloud consists of atomic hydrogen gas, interstellar plasma is quasineutral. Hydrogen atoms and plasma protons interact through a charge exchange process. Magnetic felds and radiative processes are ignored in the model. The influence of heat conduction within plasma on the interaction between a cloud and plasma is studied. We consider the extreme case and assume that hot plasma electrons instantly heat the plasma in the interaction region and that plasma flow can be described as isothermal. Using the two-component model of the interaction of cold neutral cloud and hot plasma, we estimate the lifetime of interstellar clouds. We focus on the clouds typical for the cluster of local interstellar clouds embedded in the hot Local Bubble and give an estimate of the lifetime of the Local interstellar cloud where the Sun currently travels. The charge transfer between highly charged plasma ions and neutral atoms generates X-ray emission. We assume typical abundance of heavy ions for the Local Bubble plasma and estimate the X-ray emissivity due to charge exchange from the interface between cold neutral cloud and hot plasma. Our results show that charge exchange X-ray emission from the neutral-plasma interfaces can be a non-negligible fraction of the observed X-ray emission.Comment: 9 pages, 7 figure

    The Explication Defence of Arguments from Reference

    Get PDF
    In a number of influential papers, Machery, Mallon, Nichols and Stich have presented a powerful critique of so-called arguments from reference, arguments that assume that a particular theory of reference is correct in order to establish a substantive conclusion. The critique is that, due to cross-cultural variation in semantic intuitions supposedly undermining the standard methodology for theorising about reference, the assumption that a theory of reference is correct is unjustified. I argue that the many extant responses to Machery et al.’s critique do little for the proponent of an argument from reference, as they do not show how to justify the problematic assumption. I then argue that it can in principle be justified by an appeal to Carnapian explication. I show how to apply the explication defence to arguments from reference given by Andreasen (for the biological reality of race) and by Churchland (against the existence of beliefs and desires)

    Research on health transition in Africa: time for action

    Get PDF
    With rapidly increasing globalization, trends towards unhealthy diets, obesity, sedentary lifestyles and unhealthy habits are resulting in an increased worldwide burden of chronic non-communicable diseases (NCDs). In Africa this means that health systems face the challenge of an increasing burden of NCDs and of continuing high morbidity and mortality from communicable diseases. This health transition represents an enormous challenge to Africa as the region with the least resources for an effective response. Whereas previous epidemics, including HIV, have caught Africa unprepared, the opportunity now arises to take the advancing wave of health transition in Africa seriously. Health research has a key role to play in meeting health and development goals, and must be responsive to changing disease patterns, such as health transition. There is an urgent need for research on health transition in Africa to enable countries to respond effectively to rapidly changing health needs
    corecore