Display omitted
•Precise biomass characterization requires analytical techniques combination.•Analytical tools concomitantly explore molecular-microstructural biomass level.•Instruments progress ...allows analytical complex samples advances.•Biomass composition affects the bioconversion yield and production economy.•PAT, real-time monitoring, ensures economical and mass-energy balance process.
The trend in the modern world is to replace fossil fuels with green energy sources in order to reduce their environmental impact. The biorefinery industry, within this premise, needs to establish quantitative and qualitative analytical methods to better understand lignocellulosic biomass composition and structure. This paper presents chemical techniques (chromatography, thermal analysis, HRMS, FTIR, NIR, and NMR) and physicochemical techniques (XRD, optical and electron microscopy techniques – Confocal fluorescence, Raman, SPM, AFM, SEM, and TEM) for the microstructural characterization of lignocellulosic biomass and its derivatives. Each of these tools provides different and complementary information regarding molecular and microstructural composition of lignocellulosic biomass. Understanding these properties is essential for the design and operation of associated biomass conversion processing facilities. PAT, monitored in real-time, ensures an economical and balanced mass-energy process. This review aimed to help researchers select the most suitable analytical technique with which to investigate biomass feedstocks with recalcitrant natures.
The Internet of Things (IoT) is based on interconnection of intelligent and addressable devices, allowing their autonomy and proactive behavior with Internet connectivity. Data dissemination in IoT ...usually depends on the application and requires context-aware routing protocols that must include auto-configuration features (which adapt the behavior of the network at runtime, based on context information). This paper proposes an approach for IoT route selection using fuzzy logic in order to attain the requirements of specific applications. In this case, fuzzy logic is used to translate in math terms the imprecise information expressed by a set of linguistic rules. For this purpose, four Objective Functions (OFs) are proposed for the Routing Protocol for Low Power and Loss Networks (RPL); such OFs are dynamically selected based on context information. The aforementioned OFs are generated from the fusion of the following metrics: Expected Transmission Count (ETX), Number of Hops (NH) and Energy Consumed (EC). The experiments performed through simulation, associated with the statistical data analysis, conclude that this proposal provides high reliability by successfully delivering nearly 100% of data packets, low delay for data delivery and increase in QoS. In addition, an 30% improvement is attained in the network life time when using one of proposed objective function, keeping the devices alive for longer duration.
Recent evidence suggests that the duration of protection by bacillus Calmette-Guérin (BCG) may exceed previous estimates with potential implications for estimating clinical and cost-efficacy.
To ...estimate the protection and duration of protection provided by BCG vaccination against tuberculosis, explore how this protection changes with time since vaccination, and examine the reasons behind the variation in protection and the rate of waning of protection.
Electronic databases including MEDLINE, Excerpta Medica Database (EMBASE), Cochrane Databases, NHS Economic Evaluation Database (NHS EED), Database of Abstracts of Reviews of Effects (DARE), Web of Knowledge, Biosciences Information Service (BIOSIS), Latin American and Caribbean Health Sciences Literature (LILACs), MEDCARIB Database, Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched from inception to May 2009. Index to Theses, System for Information on Grey Literature in Europe (SIGLE), Centre for Agricultural Bioscience International (CABI) Abstracts, Scopus, Article First, Academic Complete, Africa-Wide Information, Google Scholar, Global Health, British National Bibliography for Report Literature, and clinical trial registration websites were searched from inception to October 2009.
Electronic databases searches, screening of identified studies, data extraction and analysis were undertaken. Meta-analysis was used to present numerical and graphical summaries of clinical efficacy and efficacy by time since vaccination. Evidence of heterogeneity was assessed using the tau-squared statistic. Meta-regression allowed the investigation of observed heterogeneity. Factors investigated included BCG strain, latitude, stringency of pre-BCG vaccination tuberculin testing, age at vaccination, site of disease, study design and vulnerability to biases. Rate of waning of protection was estimated using the ratio of the measure of efficacy after 10 years compared with the efficacy in the first 10 years of a study.
Study selection. A total of 21,030 references were identified, providing data on 132 studies after abstract and full-text review. Efficacy. Protection against pulmonary tuberculosis in adults is variable, ranging from substantial protection in the UK MRC trial {rate ratio 0.22 95% confidence interval (CI) 0.16 to 0.31}, to absence of clinically important benefit, as in the large Chingleput trial rate ratio 1.05 (95% CI 0.88 to 1.25) and greater in latitudes further away from the equator. BCG vaccination efficacy was usually high, and varied little by form of disease (with higher protection against meningeal and miliary tuberculosis) or study design when BCG vaccination was given only to infants or to children after strict screening for tuberculin sensitivity. High levels of protection against death were observed from both trials and observational studies. The observed protective effect of BCG vaccination did not differ by the strain of BCG vaccine used in trials.
Reviewed studies showed that BCG vaccination protects against pulmonary and extrapulmonary tuberculosis for up to 10 years. Most studies either did not follow up participants for long enough or had very few cases after 15 years. This should not be taken to indicate an absence of effect: five studies (one trial and four observational studies) provided evidence of measurable protection at least 15 years after vaccination. Efficacy declined with time. The rate of decline was variable, with faster decline in latitudes further from the equator and in situations where BCG vaccination was given to tuberculin-sensitive participants after stringent tuberculin testing.
The main limitation of this review relates to quality of included trials, most of which were conducted before current standards for reporting were formulated. In addition, data were lacking in some areas and the review had to rely on evidence from observational studies.
BCG vaccination protection against tuberculosis varies between populations, to an extent that cannot be attributed to chance alone. Failure to exclude those already sensitised to mycobacteria and study latitude closer to the equator were associated with lower efficacy. These factors explained most of the observed variation. There is good evidence that BCG vaccination protection declines with time and that protection can last for up to 10 years. Data on protection beyond 15 years are limited; however, a small number of trials and observational studies suggest that BCG vaccination may protect for longer. Further studies are required to investigate the duration of protection by BCG vaccination.
The National Institute for Health Research Health Technology Assessment programme.
Is High Blood Pressure Self-Protection for the Brain? Warnert, Esther A.H; Rodrigues, Jonathan C.L; Burchell, Amy E ...
Circulation research,
2016-December-9, 2016-Dec-09, 2016-12-09, 20161209, Letnik:
119, Številka:
12
Journal Article
Recenzirano
Odprti dostop
RATIONALE:Data from animal models of hypertension indicate that high blood pressure may develop as a vital mechanism to maintain adequate blood flow to the brain. We propose that congenital vascular ...variants of the posterior cerebral circulation and cerebral hypoperfusion could partially explain the pathogenesis of essential hypertension, which remains enigmatic in 95% of patients.
OBJECTIVE:To evaluate the role of the cerebral circulation in the pathophysiology of hypertension.
METHODS AND RESULTS:We completed a series of retrospective and mechanistic case-control magnetic resonance imaging and physiological studies in normotensive and hypertensive humans (n=259). Interestingly, in humans with hypertension, we report a higher prevalence of congenital cerebrovascular variants; vertebral artery hypoplasia, and an incomplete posterior circle of Willis, which were coupled with increased cerebral vascular resistance, reduced cerebral blood flow, and a higher incidence of lacunar type infarcts. Causally, cerebral vascular resistance was elevated before the onset of hypertension and elevated sympathetic nerve activity (n=126). Interestingly, untreated hypertensive patients (n=20) had a cerebral blood flow similar to age-matched controls (n=28). However, participants receiving antihypertensive therapy (with blood pressure controlled below target levels) had reduced cerebral perfusion (n=19). Finally, elevated cerebral vascular resistance was a predictor of hypertension, suggesting that it may be a novel prognostic or diagnostic marker (n=126).
CONCLUSIONS:Our data indicate that congenital cerebrovascular variants in the posterior circulation and the associated cerebral hypoperfusion may be a factor in triggering hypertension. Therefore, lowering blood pressure may worsen cerebral perfusion in susceptible individuals.
Human mobility has a significant impact on several layers of society, from infrastructural planning and economics to the spread of diseases and crime. Representing the system as a complex network, in ...which nodes are assigned to regions (e.g., a city) and links indicate the flow of people between two of them, physics-inspired models have been proposed to quantify the number of people migrating from one city to the other. Despite the advances made by these models, our ability to predict the number of commuters and reconstruct mobility networks remains limited. Here, we propose an alternative approach using machine learning and 22 urban indicators to predict the flow of people and reconstruct the intercity commuters network. Our results reveal that predictions based on machine learning algorithms and urban indicators can reconstruct the commuters network with 90.4% of accuracy and describe 77.6% of the variance observed in the flow of people between cities. We also identify essential features to recover the network structure and the urban indicators mostly related to commuting patterns. As previously reported, distance plays a significant role in commuting, but other indicators, such as Gross Domestic Product (GDP) and unemployment rate, are also driven-forces for people to commute. We believe that our results shed new lights on the modeling of migration and reinforce the role of urban indicators on commuting patterns. Also, because link-prediction and network reconstruction are still open challenges in network science, our results have implications in other areas, like economics, social sciences, and biology, where node attributes can give us information about the existence of links connecting entities in the network.
Abstract
The left ventricular ejection fraction does not accurately predict exercise capacity or symptom severity and has a limited role in predicting prognosis in heart failure. A better method of ...assessing ventricular performance is needed to aid understanding of the pathophysiological mechanisms and guide management in conditions such as heart failure. In this study, we propose two novel measures to quantify myocardial performance, the global longitudinal active strain energy (GLASE) and its density (GLASED) and compare them to existing measures in normal and diseased left ventricles. GLASED calculates the work done per unit volume of muscle (energy density) by combining information from myocardial strain and wall stress (contractile force per unit cross sectional area). Magnetic resonance images were obtained from 183 individuals forming four cohorts (normal, hypertension, dilated cardiomyopathy, and cardiac amyloidosis). GLASE and GLASED were compared with the standard ejection fraction, the corrected ejection fraction, myocardial strains, stroke work and myocardial forces. Myocardial shortening was decreased in all disease cohorts. Longitudinal stress was normal in hypertension, increased in dilated cardiomyopathy and severely decreased in amyloid heart disease. GLASE was increased in hypertension. GLASED was mildly reduced in hypertension (1.39 ± 0.65 kJ/m
3
), moderately reduced in dilated cardiomyopathy (0.86 ± 0.45 kJ/m
3
) and severely reduced in amyloid heart disease (0.42 ± 0.28 kJ/m
3
) compared to the control cohort (1.94 ± 0.49 kJ/m
3
). GLASED progressively decreased in the hypertension, dilated cardiomyopathy and cardiac amyloid cohorts indicating that mechanical work done and systolic performance is severely reduced in cardiac amyloid despite the relatively preserved ejection fraction. GLASED provides a new technique for assessing left ventricular myocardial health and contractile function.
the COVID-19 pandemic poses a high risk to older people. The aim of this article is to provide a rapid overview of the COVID-19 literature, with a specific focus on older adults. We frame our ...findings within an overview of the disease and have also evaluated the inclusion of older people within forthcoming clinical trials.
we searched PubMed and bioRxiv/medRxiv to identify English language papers describing the testing, treatment and prognosis of COVID-19. PubMed and bioRxiv/medRxiv searches took place on 20 and 24 March 2020, respectively.
screening of over 1,100 peer-reviewed and pre-print papers yielded n = 22 on COVID-19 testing, n = 15 on treatment and n = 13 on prognosis. Viral polymerase chain reaction (PCR) and serology are the mainstays of testing, but a positive diagnosis may be increasingly supported by radiological findings. The current evidence for the effectiveness of antiviral, corticosteroid and immunotherapies is inconclusive, although trial data are largely based on younger people. In addition to age, male gender and comorbidities, specific laboratory and radiology findings are important prognostic factors. Evidence suggests that social distancing policies could have important negative consequences, particularly if in place for an extended period.
given the established association between increasing age and poor prognosis in COVID-19, we anticipate that this rapid review of the current and emergent evidence might form a basis on which future work can be established. Exclusion of older people, particularly those with comorbidities, from clinical trials is well recognised and is potentially being perpetuated in the field of current COVID-19 research.
•A double skin façade (DSF) applied in a test cell is designed and analyzed.•Thermocouples K type is used to measure the temperatures and hot wire anemometers for the air velocity.•Ansys CFX ...simulations are made to obtain a better analysis of heat transfer and airflow.•Results of an uninterrupted 3-day measurement sequence are presented.•Results show that DSF can contribute to the reduction of the temperature of the wall faces and contribute with the reducing of the heat gains in the indoor environment.
This paper investigates the efficiency of a naturally ventilated double-skin façade (DSF) built in a test cell focusing on the airflow and heat convection of the cavity formed by DSF. The study covers measurements of the test cell and their numerical simulation. DSFs have been widely researched worldwide, since they contribute to the thermal performance of the internal environment and to energy savings by eliminating mechanical conditioning systems. For data acquisition, type K surface thermocouples are installed on the wall faces of the test cell and the additional façade, that is, on the inner and outer face of the wall of the test cell and the inner face of the external one. Furthermore, hot wire anemometers are positioned so as to obtain the air velocity in the lower and upper openings of the cavity, which has an air layer thickness of 0.1 m. The results show that the DSF presence contributes to a decrease of the temperature inside the environment because it inhibits the direct solar radiation. Measurement of the faces shows that at 4:00 p.m. the temperature reaches their maximum values. These values are equal to 25.6 °C on the inner face of the façade and 23.6 °C on the inner face of the test cell, while the outdoor temperature presents values equal to 23.1 °C at this time.
PDF
