471 research outputs found

    Development of climate-based thermal comfort ranges from existing data: Analysis of the Smart Controls and thermal comfort (SCATS) database

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    Despite the multifaceted nature of notion of thermal comfort, designers have embraced a very strict definition of it, which consists of very tight and static environments, were transition and stimuli are not admitted, and with very narrow ranges of microclimatic parameters required equally for all the subjects. This neglects all the potential implications related to different users. However, when it comes to thermal comfort, the long-term history of subjects and their climatic background play a pivotal role towards their own thermal sensations and preferences. In this work, to address these diversities, the authors analysed the existing database of the Smart Controls and Thermal Comfort (SCATS) project, which was built from monitoring and survey campaigns conducted in the late 90s in five different European countries. Data were studied by means of statistical techniques to grasp and define the potential combined influence of climatic location, seasonal variations, subjective variables and ventilation modes on the occupants’ thermal feeling and preference. Different scenarios recommended by standard EN 16798 were tested to address the differences in the thermal feelings of users living in different European countries. Finally, country-based operative temperatures that optimize users’ thermal feeling and preference were determined. Results highlight that users in different countries differently evaluate indoor thermal parameters both in terms of thermal feeling and thermal preferences. This results in differences among countries for acceptability levels associated with standardised indoor conditions. Furthermore, the results highlight the importance of air movement to improve acceptability at higher indoor temperatures for all the countries

    Naturalness and theoretical constraints on the Higgs boson mass

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    Arbitrary regularization dependent parameters in Quantum Field Theory are usually fixed on symmetry or phenomenology grounds. We verify that the quadratically divergent behavior responsible for the lack of naturalness in the Standard Model (SM) is intrinsically arbitrary and regularization dependent. While quadratic divergences are welcome for instance in effective models of low energy QCD, they pose a problem in the SM treated as an effective theory in the Higgs sector. Being the very existence of quadratic divergences a matter of debate, a plausible scenario is to search for a symmetry requirement that could fix the arbitrary coefficient of the leading quadratic behavior to the Higgs boson mass to zero. We show that this is possible employing consistency of scale symmetry breaking by quantum corrections. Besides eliminating a fine-tuning problem and restoring validity of perturbation theory, this requirement allows to construct bounds for the Higgs boson mass in terms of δm2/mH2\delta m^2/m^2_H (where mHm_H is the renormalized Higgs mass and δm2\delta m^2 is the 1-loop Higgs mass correction). Whereas δm2/mH2<1\delta m^2/m^2_H<1 (perturbative regime) in this scenario allows the Higgs boson mass around the current accepted value, the inclusion of the quadratic divergence demands δm2/mH2\delta m^2/m^2_H arbitrarily large to reach that experimental value.Comment: 6 pages, 4 figure

    Variability in black carbon mass concentration in surface snow at Svalbard

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    Black carbon (BC) is a significant forcing agent in the Arctic, but substantial uncertainty remains to quantify its climate effects due to the complexity of the different mechanisms involved, in particular related to processes in the snowpack after deposition. In this study, we provide detailed and unique information on the evolution and variability in BC content in the upper surface snow layer during the spring period in Svalbard (Ny-Ålesund). A total of two different snow-sampling strategies were adopted during spring 2014 (from 1 April to 24 June) and during a specific period in 2015 (28 April to 1 May), providing the refractory BC (rBC) mass concentration variability on a seasonal variability with a daily resolution (hereafter seasonal/daily) and daily variability with an hourly sampling resolution (hereafter daily/hourly) timescales. The present work aims to identify which atmospheric variables could interact with and modify the mass concentration of BC in the upper snowpack, which is the snow layer where BC particles affects the snow albedo. Atmospheric, meteorological and snow-related physico-chemical parameters were considered in a multiple linear regression model to identify the factors that could explain the variations in BC mass concentrations during the observation period. Precipitation events were the main drivers of the BC variability during the seasonal experiment; however, in the high-resolution sampling, a negative association has been found. Snow metamorphism and the activation of local sources (Ny-Ålesund was a coal mine settlement) during the snowmelt periods appeared to play a non-negligible role. The statistical analysis suggests that the BC content in the snow is not directly associated to the atmospheric BC load

    Symmetry preserving regularization with a cutoff

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    A Lorentz and gauge symmetry preserving regularization method is proposed in 4 dimension based on momentum cutoff. We use the conditions of gauge invariance or freedom of shift of the loop-momentum to define the evaluation of the terms carrying Lorentz indices, e.g. proportional to k_{\mu}k_{\nu}. The remaining scalar integrals are calculated with a four dimensional momentum cutoff. The finite terms (independent of the cutoff) are unambiguous and agree with the result of dimensional regularization.Comment: 12 pages, 1 figure, v2 references adde

    The Making of a Mobile Caliphate State in the African Sahel

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    The goal of this chapter is to thoroughly understand the context of the dominant jihadist narratives and the nature of their appeal in the Sahelian region. All these jihadist ideologies are based on a peculiar Salafi Radicalism that aimed to transform the state and society by methods of preaching and violence. Therefore, studying and analyzing the principles of the Salafist discourse as a political project helps us to understand its points of strengths and weaknesses. In addition, we can be better look at the future trends and prospects of violent jihadist groups in the African Sahel. The roots of this Islamic discourse as a political project may be attributed to what Lunay and Suarez call the “Islamic domain.” The rise of violent radical Islamism represents drive from the internal political and socioeconomic dynamics evolving in each Sahelian state. However, the struggle and rivalry of jihadist ideologies after the military defeat of Daesh in Mosul is important at a time when thousands of fighters who have survived the civil wars in Iraq, Syria, and Libya are looking for new jihadist fields

    To the problem of doctor’s tactics in patients with pleuritis of uncertain genesis

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    Polyetiologic features of pleuritis lesions, doctors' particular speciality and the lack of standards give rise to inevitable difficulties in making diagnosis, while the introduction of modern research innovations solves only specific problems. All above mentioned issues require the introduction of new organizational technologies. Retrospective analysis of medical records of 968 patients performed at the centre of the Novokuznetsk State Clinical Tuberculous Hospital showed the efficacy of algorithm usage in specialized medical care and doctor's tactics. In 91% of patients the period for diagnosis verification was 10,4+2,0 days, and idiopathic pleuritis shared 4% of patients.Полиэтиологичность поражений плевры, узкая специализация врачей и отсутствие стандартов порождают неизбежные трудности диагностики, а внедрение наукоемких исследований решает лишь частные проблемы. Необходим пересмотр ситуации, использование новых организационных технологий. Данные ретроспективного анализа историй болезни 968 пациентов плеврального центра при ГУЗ «НКТБ», показали эффективность специализированной помощи и врачебной тактики, формализованной в виде алгоритма. Для 91% больных время верификации диагноза в среднем составляет 10,4+2,0 дней, а доля идиопатических плевритов — 4%

    A Review of Multi- Compartment Infectious Disease Models

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156488/2/insr12402.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156488/1/insr12402_am.pd

    Clinical features of current, diagnostics of tuberculous and malignant pleurisies

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    Clinical current, features of semiology and efficacy of diagnostic methods were studied on an example of 626 patients with a pleural pathology (401 - tuberculous, 225 - malignant pleurisies), examined at the specialized pleural department of Clinical Tuberculosis Hospital of Novokuznetsk. Typical cases of malignancies had the following characteristics: absence of inflammation symptoms, progressing dyspnoea and-or chest pain, inexhaustibility and haemorrhagic character of pleural effusion. In this group sensitivity and specificity of cytologic examination of pleural effusion was 51,9% and 98,0%, pleural needle biopsy (PNB) - 60,8% and 100% accordingly. 65% of tuberculous pleurisies were verified by PNB. Sensitivity PNB was accounted 80,8% at specificity 99,2%. Non-specific results of PNB in the cases high evidence of ТВ etiology pleurisy, using of another methods is necessary (test-therapy of a tuberculosis, organizational methods: algorithm, supervision).Клиническое течение, особенности симптоматики и эффективность диагностических методов рассмотрены на примере 626 больных с плевральной патологией (401 - туберкулезные, 225 - злокачественные плевриты), обследованных в специализированном плевральном отделении клинической туберкулезной больницы г. Новокузнецка. В типичных случаях злокачественность поражения плевры отличает отсутствие симптомов воспалительной интоксикации, прогрессирующая одышка и/или торакалгии, неиссякаемость и геморрагический характер экссудата. В этой группе отмечается высокая чувствительность и специфичность цитологического исследования плеврального выпота - 51,9% и 98,0%, игловой биопсии плевры (ПБ) - 60,8% и 100% соответственно. У 65% больных туберкулезом основным методом верификации плеврита является ПБ. Чувствительность ПБ составила 80,8% при специфичности 99,2%. Неспецифический результат ПБ при высокой вероятности туберкулезной этиологии плеврита предполагает использование других методов: тест-терапия туберкулеза, организационные (алгоритм, наблюдение)

    The Hepatokine TSK does not affect brown fat thermogenic capacity, body weight gain, and glucose homeostasis

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    Objectives Hepatokines are proteins secreted by the liver that impact the functions of the liver and various tissues through autocrine, paracrine, and endocrine signaling. Recently, Tsukushi (TSK) was identified as a new hepatokine that is induced by obesity and cold exposure. It was proposed that TSK controls sympathetic innervation and thermogenesis in brown adipose tissue (BAT) and that loss of TSK protects against diet-induced obesity and improves glucose homeostasis. Here we report the impact of deleting and/or overexpressing TSK on BAT thermogenic capacity, body weight regulation, and glucose homeostasis. Methods We measured the expression of thermogenic genes and markers of BAT innervation and activation in TSK-null and TSK-overexpressing mice. Body weight, body temperature, and parameters of glucose homeostasis were also assessed in the context of TSK loss and overexpression. Results The loss of TSK did not affect the thermogenic activation of BAT. We found that TSK-null mice were not protected against the development of obesity and did not show improvement in glucose tolerance. The overexpression of TSK also failed to modulate thermogenesis, body weight gain, and glucose homeostasis in mice
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