831 research outputs found

    How the Biden Administration Can Reinvigorate Global Health Security, Institutions, and Governance

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    The tragedy of COVID-19 can be fertile soil for deep structural reforms. President Biden can both bolster the immediate responses to COVID-19 and its vast ramifications, and spearhead lasting changes to create a healthier and safer world, from which the United States would richly benefit. The agenda we propose for President Biden is ambitious, yet US. bold leadership on global health will benefit all people, including Americans, and is in the U.S. national interest Along with responding to the COVID-19 domestically, the Biden administration should enhance U.S.-initiatives home, expanding the Global Health Security Agenda and restoring and reinvigorating the PREDICT animal virus identification and tracking project, while ensuring that the U.S. Strategic National Stockpile is fully stocked with critical medical supplies and expanding research and development of antimicrobials. To enable the world to benefit from U.S. science – and to benefit from it – the administration should support the Open Science movement. And the administration should work with Congress to use devote 2% of past and future U.S. domestic COVID-19 spending to the global response, extend a debt moratorium, and enhance debt cancellation. The United States should lead strengthened global governance for health security, beginning with proposing a doubling of mandatory WHO contributions, WHO reform including enhanced civil society participation, and strengthening the International Health Regulations (2005). Meanwhile, along with joining and funding the global vaccine distribution mechanism, COVAX, the Biden administration should propose creating a permanent facility for distributing PPE and other medical supplies and equipment, diagnostics, therapies, and vaccines during epidemics and pandemics. And by supporting use of TRIPS-flexibilities and, going further, supporting suspending intellectual property rights related to COVID-19 technologies, expanding production and increasing access, the administration would enable expanded global production, enhanced access, and lower prices. Finally, the Biden administration should lead a collaborative global effort to ensure that the global health architecture is firmly based in human rights, which would enhance equity and accountability and elevate the voices and priorities of marginalized populations. At its foundation would be the Framework Convention on Global Health, a proposed treaty that, if adopted, would strengthen implementation of the right to health and promote global health equity, while a Right to Health Capacity Fund could support right-to-health advocacy, accountability, and participation mechanisms

    Radiation hardness of Ga0.5In0.5 P/GaAs tandem solar cells

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    The radiation hardness of a two-junction monolithic Ga sub 0.5 In sub 0.5 P/GaAs cell with tunnel junction interconnect was investigated. Related single junction cells were also studied to identify the origins of the radiation losses. The optimal design of the cell is discussed. The air mass efficiency of an optimized tandem cell after irradiation with 10(exp 15) cm (-2) 1 MeV electrons is estimated to be 20 percent using currently available technology

    Experimental and modeling analysis of internal luminescence in III-V solar cells

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    In high quality solar cells, the internal luminescence can be harnessed to enhance the overall performance. Internal confinement of the photons can lead to an increased open-circuit voltage and short-circuit current. Alternatively, in multijunction solar cells the photons can be coupled from a higher bandgap junction to a lower bandgap junction for enhanced performance. We model the solar cell as an optical cavity and compare calculated performance characteristics with measurements. We also describe how very high luminescent coupling alleviates the need for top-cell thinning to achieve current-matching

    The Living Together Arrangement: Social Work and the Lost Client

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    A recent research study suggests that persons living together outside of marriage do not view social work services as a potential source of help for problems brought into the living together arrangement, those common to all intimate long-range dyadic relationships or those directly related to choice of lifestyle. A multi-faceted approach is suggested which would aim at reaching this potential client group in a climate which will neither stigmatize or judge the alternate lifestyle or the persons who practice it

    The Global Health and Care Worker Compact: Evidence Base and Policy Considerations

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    Background During the COVID-19 pandemic, and recognising the sacrifice of health and care workers alongside discrimination, violence, poor working conditions and other violations of their rights, health and safety, in 2021 the World Health Assembly requested WHO to develop a global health and care worker compact, building on existing normative documentation, to provide guidance to ‘protect health and care workers and safeguard their rights’. Methods A review of existing international law and other normative documents was conducted. We manually searched five main sets of international instruments: (1) International Labour Organization conventions and recommendations; (2) WHO documents; (3) United Nations (UN) human rights treaties and related documents; (4) UN Security Council and General Assembly resolutions and (5) the Geneva Conventions and Additional Protocols. We included only legal or other normative documents with a global or regional focus directly addressing or relevant to health and care workers or workers overall. Results More than 70 documents met our search criteria. Collectively, they fell into four domains, within which we identified 10 distinct areas: (1) preventing harm, encompassing (A) occupational hazards, (B) violence and harassment and (C) attacks in situations of fragility, conflict and violence; (2) inclusivity, encompassing (A) non-discrimination and equality; (3) providing support, encompassing (A) fair and equitable remuneration, (B) social protection and (C) enabling work environments and (4) safeguarding rights, encompassing (A) freedom of association and collective bargaining and (B) whistle-blower protections and freedom from retaliation. Discussion A robust legal and policy framework exists for supporting health and care workers and safeguarding their rights. Specific human rights, the right to health overall, and other binding and non-binding legal documents provide firm grounding for the compact. However, these existing commitments are not being fully met. Implementing the compact will require more effective governance mechanisms and new policies, in partnership with health and care workers themselves

    Effects of internal luminescence and internal optics on V-oc and J(sc) of III-V solar cells

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    For solar cells dominated by radiative recombination, the performance can be significantly enhanced by improving the internal optics. Internally radiated photons can be directly emitted from the cell, but if confined by good internal reflectors at the front and back of the cell they can also be re-absorbed with a significant probability. This so-called photon recycling leads to an increase in the equilibrium minority carrier concentration and therefore the open-circuit voltage, Voc. In multijunction cells, the internal luminescence from a particular junction can also be coupled into a lower bandgap junction where it generates photocurrent in addition to the externally generated photocurrent, and affects the overall performance of the tandem. We demonstrate and discuss the implications of a detailed model that we have developed for real, non-idealized solar cells that calculates the external luminescent efficiency, accounting for wavelength-dependent optical properties in each layer, parasitic optical and electrical losses, multiple reflections within the cell and isotropic internal emission. The calculation leads to Voc, and we show data on high quality GaAs cells that agree with the trends in the model as the optics are systematically varied. For multijunction cells the calculation also leads to the luminescent coupling efficiency, and we show data on GaInP/GaAs tandems where the trends also agree as the coupling is systematically varied. In both cases, the effects of the optics are most prominent in cells with good material quality. The model is applicable to any solar cell for which the optical properties of each layer are well-characterized, and can be used to explore a wide phase space of design for single junction and multijunction solar cells

    Sex Differences in Left Ventricular Electrical Dyssynchrony and Outcomes with Cardiac Resynchronization Therapy

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    BACKGROUND: Women seem to derive more benefit from cardiac resynchronization therapy (CRT) than men, even after accounting for the higher burden of risk factors for nonresponse often observed in men. OBJECTIVE: To assess for sex-specific differences in left ventricular (LV) electrical dyssynchrony as a contributing electrophysiological explanation for the greater degree of CRT benefit among women. METHODS: We compared the extent of baseline LV electrical dyssynchrony, as measured by the QRS area (QRSA), among men and women with left bundle branch block (LBBB) undergoing CRT at Duke University (n = 492, 35% women) overall and in relation to baseline QRS characteristics using independent sample t tests and Pearson correlation coefficients. Cox regression analyses were used to relate sex, QRSA, and QRS characteristics to the risk of cardiac transplantation, LV assist device implant, or death. RESULTS: Although the mean QRS duration (QRSd) did not differ by sex, QRSA was greater for women vs men (113.8 μVs vs 98.2 μVs, P < .001), owing to differences in the QRSd <150 ms subgroup (92.3 ± 28.7 μVs vs 67.6 ± 26.2 μVs, P < .001). Among those with nonstrict LBBB, mean QRSd was similar but QRSA was significantly greater among women than men (96.0 ± 25.0 μVs vs 63.6 ± 26.2 μVs, P < .001). QRSA was similar among men and women with strict LBBB (P = .533). Female sex was associated with better long-term outcomes in an unadjusted model (hazard ratio 0.623, confidence interval 0.454–0.857, P = .004) but sex no longer predicted outcomes after accounting for differences in QRSA. CONCLUSIONS: Our study suggests that sex-specific differences in LV dyssynchrony contribute to greater CRT benefit among women. Standard QRSd and morphology assessments seem to underestimate the extent of LV electrical dyssynchrony among women with LBBB

    Management and Outcome of Permanent Pacemaker and Implantable Cardioverter-Defibrillator Infections

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    ObjectivesWe describe the management and outcome of permanent pacemaker (PPM) and implantable cardioverter-defibrillator (ICD) infections in a large cohort of patients seen at a tertiary care facility with expertise in device lead extraction.BackgroundInfection is a serious complication of PPM and ICD implantation. Optimal care of patients with these cardiac device infections (CDI) is not well defined.MethodsA retrospective review of all patients with CDI admitted to Mayo Clinic Rochester between January 1, 1991, and December 31, 2003, was conducted. Demographic and clinical data were collected, and descriptive analysis was performed.ResultsA total of 189 patients met the criteria for CDI (138 PPM, 51 ICD). The median age of the patients was 71.2 years. Generator pocket infection (69%) and device-related endocarditis (23%) were the most common clinical presentations. Coagulase-negative staphylococci and Staphylococcus aureus, in 42% and 29% of cases, respectively, were the leading pathogens for CDI. Most patients (98%) underwent complete device removal. Duration of antibiotic therapy after device removal was based on clinical presentation and causative organism (median duration of 18 days for pocket infection vs. 28 days for endocarditis; 28 days for S. aureusinfection vs. 14 days for coagulase-negative staphylococci infection [p < 0.001]). Median follow-up after hospital discharge was 175 days. Ninety-six percent of patients were cured with both complete device removal and antibiotic administration.ConclusionsCure of CDI is achievable in the large majority of patients treated with an aggressive approach of combined antimicrobial treatment and complete device removal. Based on findings of our large retrospective institutional survey and previously published data, we submit proposed management guidelines of CDI

    Mice That Express Human Interleukin-8 Have Increased Mobilization of Immature Myeloid Cells, Which Exacerbates Inflammation and Accelerates Colon Carcinogenesis

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    Background & Aims Interleukin (IL)-8 has an important role in initiating inflammation in humans, attracting immune cells such as neutrophils through their receptors CXCR1 and CXCR2. IL-8 has been proposed to contribute to chronic inflammation and cancer. However, mice do not have the IL-8 gene, so human cancer cell lines and xenograft studies have been used to study the role of IL-8 in colon and gastric carcinogenesis. We generated mice that carry a bacterial artificial chromosome that encompasses the entire human IL-8 gene, including its regulatory elements (IL-8Tg mice). Methods We studied the effects of IL-8 expression in APCmin[superscript +/−] mice and IL-8Tg mice given azoxymethane and dextran sodium sulfate (DSS). We also examined the effects of IL-8 expression in gastric cancer in INS-GAS mice that overexpress gastrin and IL-8Tg mice infected with Helicobacter felis. Results In IL-8Tg mice, expression of human IL-8 was controlled by its own regulatory elements, with virtually no messenger RNA or protein detectable under basal conditions. IL-8 was strongly up-regulated on systemic or local inflammatory stimulation, increasing mobilization of immature CD11b[superscript +]Gr-1[superscript +] myeloid cells (IMCs) with thioglycolate-induced peritonitis, DSS-induced colitis, and H. felis–induced gastritis. IL-8 was increased in colorectal tumors from patients and IL-8Tg mice compared with nontumor tissues. IL-8Tg mice developed more tumors than wild-type mice following administration of azoxymethane and DSS. Expression of IL-8 increased tumorigenesis in APCmin[superscript +/−] mice compared with APCmin[superscript +/−] mice that lack IL-8; this was associated with increased numbers of IMCs and angiogenesis in the tumors. Conclusions IL-8 contributes to gastrointestinal carcinogenesis by mobilizing IMCs and might be a therapeutic target for gastrointestinal cancers

    Mice that express human interleukin-8 have increased mobilization of immature myeloid cells, which exacerbates inflammation and accelerates colon carcinogenesis

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    Background & Aims: Interleukin (IL)-8 has an important role in initiating inflammation in humans, attracting immune cells such as neutrophils through their receptors CXCR1 and CXCR2. IL-8 has been proposed to contribute to chronic inflammation and cancer. However, mice do not have the IL-8 gene, so human cancer cell lines and xenograft studies have been used to study the role of IL-8 in colon and gastric carcinogenesis. We generated mice that carry a bacterial artificial chromosome that encompasses the entire human IL-8 gene, including its regulatory elements (IL-8Tg mice). Methods: We studied the effects of IL-8 expression in APCmin+/- mice and IL-8Tg mice given azoxymethane and dextran sodium sulfate (DSS). We also examined the effects of IL-8 expression in gastric cancer in INS-GAS mice that overexpress gastrin and IL-8Tg mice infected with Helicobacter felis. Results: In IL-8Tg mice, expression of human IL-8 was controlled by its own regulatory elements, with virtually no messenger RNA or protein detectable under basal conditions. IL-8 was strongly up-regulated on systemic or local inflammatory stimulation, increasing mobilization of immature CD11b+Gr-1+ myeloid cells (IMCs) with thioglycolate-induced peritonitis, DSS-induced colitis, and H. felis-induced gastritis. IL-8 was increased in colorectal tumors from patients and IL-8Tg mice compared with nontumor tissues. IL-8Tg mice developed more tumors than wild-type mice following administration of azoxymethane and DSS. Expression of IL-8 increased tumorigenesis in APCmin+/- mice compared with APCmin+/- mice that lack IL-8; this was associated with increased numbers of IMCs and angiogenesis in the tumors. Conclusions: IL-8 contributes to gastrointestinal carcinogenesis by mobilizing IMCs and might be a therapeutic target for gastrointestinal cancers. © 2013 AGA Institute
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