63 research outputs found
The fourth-order single-switch improved super-boost converter with reduced input current ripple
This paper introduces a new single switch DC-DC fourth-order boost converter. The proposed converter is the improved version of an existing converter known as the super-boost converter. The improved super-boost ISP converter achieves a smaller input current ripple than the super-boost converter when the same parameters in passive components are used. Conversely, smaller components can be used to achieve the same input current ripple, which leads to a compact and cheaper design. A comparative evaluation showed a reduction of 37.3% of stored energy in inductors to comply with a required input current ripple in comparison with the super-boost converter for a particular design. Experimental results are provided to corroborate this benefit of the ISB proposed topology
Prevalencia de urticaria croÌnica y patologiÌas asociadas en el Centro Regional de Alergia e InmunologiÌa CliÌnica del Hospital Universitario âDr. JoseÌ Eleuterio GonzaÌlezâ, Universidad AutoÌnoma de Nuevo LeoÌn
La urticaria crónica (UC) afecta al 1% de la población general; se define por la presencia de ronchas o habones con o sin angioedema. La UC puede estar relacionada a otras enfermedades alérgicas de importancia.
ABSTRACT
Chronic urticaria (CU) affects 1% of the population and is defined as the presence of wheals with or without angioedema. It can also be associated to other allergy related pathologies
Conceptual design of the International Axion Observatory (IAXO)
The International Axion Observatory (IAXO) will be a forth generation axion
helioscope. As its primary physics goal, IAXO will look for axions or
axion-like particles (ALPs) originating in the Sun via the Primakoff conversion
of the solar plasma photons. In terms of signal-to-noise ratio, IAXO will be
about 4-5 orders of magnitude more sensitive than CAST, currently the most
powerful axion helioscope, reaching sensitivity to axion-photon couplings down
to a few GeV and thus probing a large fraction of the
currently unexplored axion and ALP parameter space. IAXO will also be sensitive
to solar axions produced by mechanisms mediated by the axion-electron coupling
with sensitivity for the first time to values of not
previously excluded by astrophysics. With several other possible physics cases,
IAXO has the potential to serve as a multi-purpose facility for generic axion
and ALP research in the next decade. In this paper we present the conceptual
design of IAXO, which follows the layout of an enhanced axion helioscope, based
on a purpose-built 20m-long 8-coils toroidal superconducting magnet. All the
eight 60cm-diameter magnet bores are equipped with focusing x-ray optics, able
to focus the signal photons into cm spots that are imaged by
ultra-low-background Micromegas x-ray detectors. The magnet is built into a
structure with elevation and azimuth drives that will allow for solar tracking
for 12 h each day.Comment: 47 pages, submitted to JINS
Compromising between European and US allergen immunotherapy schools: Discussions from GUIMIT, the Mexican immunotherapy guidelines
Background: Allergen immunotherapy (AIT) has a longstanding history and still remains the only disease-changing treatment for allergic rhinitis and asthma. Over the years 2 different schools have developed their strategies: the United States (US) and the European. Allergen extracts available in these regions are adapted to local practice. In other parts of the world, extracts from both regions
and local ones are commercialized, as in Mexico. Here, local experts developed a national AIT guideline (GUIMIT 2019) searching for compromises between both schools.
Methods: Using ADAPTE methodology for transculturizing guidelines and AGREE-II for evaluating guideline quality, GUIMIT selected 3 high-quality Main Reference Guidelines (MRGs): the European Academy of Allergy, Asthma and Immunology (EAACI) guideines, the S2k guideline of
various German-speaking medical societies (2014), and the US Practice Parameters on Allergen Immunotherapy 2011. We formulated clinical questions and based responses on the fused evidence available in the MRGs, combined with local possibilities, patient's preference, and costs. We
came across several issues on which the MRGs disagreed. These are presented here along with arguments of GUIMIT members to resolve them. GUIMIT (for a complete English version, see Supplementary data) concluded the following:
Results: Related to the diagnosis of IgE-mediated respiratory allergy, apart from skin prick testing
complementary tests (challenges, in vitro testing and molecular such as species-specific allergens) might be useful in selected cases to inform AIT composition. AIT is indicated in allergic rhinitis and suggested in allergic asthma (once controlled) and IgE-mediated atopic dermatitis. Concerning the correct subcutaneous AIT dose for compounding vials according to the US school: dosing tables and formula are given; up to 4 non-related allergens can be mixed, refraining from mixing high with low protease extracts. When using European extracts: the manufacturer's indications
should be followed; in multi-allergic patients 2 simultaneous injections can be given (100% consensus); mixing is discouraged. In Mexico only allergoid tablets are available; based on doses used in all sublingual immunotherapy (SLIT) publications referenced in MRGs, GUIMIT suggests a probable effective dose related to subcutaneous immunotherapy (SCIT) might be: 50â200% of the monthly SCIT dose given daily, maximum mixing 4 allergens. Also, a table with practical suggestions on non-evidence-existing issues, developed with a simplified Delphi method, is added.
Finally, dissemination and implementation of guidelines is briefly discussed, explaining how we used online tools for this in Mexico.
Conclusions: Countries where European and American AIT extracts are available should adjust AIT according to which school is followed
Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study
Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
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