Computational fluid dynamic and response surface methodology coupling: A new method for optimization of the duct to be used in ducted wind turbines.

Wind energy technology, particularly power generation by wind turbines, has received substantial attention due to resource depletion and global warming concerns. These concerns highlight the importance of conducting studies to enhance their efficiency by increasing their power output. The goal of this work was to combine the RSM (Response Surface Methodology (RSM) with CFD (Computational Fluid Dynamics) to discover the optimal design parameters and conditions for ducted wind turbines. To that purpose, twenty-seven runs were chosen using Central Composite Design (CCD) in the design phase. Duct simulation was performed by employing different dimensional parameters and feeding them into a third-order polynomial that fitted to an eight-order function. The analyzed runs discussed the maximum available wind velocity and power at the throat area of the various designed ducts. The wind-enhanced power and speed were studied under different design parameters, and their effects were discussed. The optimum design conditions to capture maximum power were 0.16 m, 2, and 1.5 for design parameters of the duct's throat diameter, contraction ratio, and length-to-throat diameter ratio, respectively. A good selection of design parameters can increase the outpour power up to six times as a general result. By modeling CFD simulations using the RSM method, it is possible to minimize the time and cost of calculation to find the optimized range for the design parameters of the ducts.

Kinetics, mechanism, and tautomerism in ametryn acid hydrolysis: From molecular structure to environmental impacts.

The excessive use of pesticides and the demand for environmentally friendly compounds have driven the focus to detailed studies of the environmental destination of these compounds. Degradation by hydrolysis of pesticides, when released into the soil, can result in the formation of metabolites with potentially adverse effects on the environment. Moving in this direction, we investigated the mechanism of acid hydrolysis of the herbicide ametryn (AMT) and predicted the toxicities of metabolites through experimental and theoretical approaches. The formation of ionized hydroxyatrazine (HA) occurs with the release of the SCH3- group and the addition of H3O+ to the triazine ring. The tautomerization reactions privileged the conversion of AMT into HA. Furthermore, the ionized HA is stabilized by an intramolecular reaction that provides the molecule in two tautomeric states. Experimentally, the hydrolysis of AMT was obtained under acidic conditions and at room temperature with HA as the main product. HA was isolated in a solid state through its crystallization as organic counterions. The mechanism of conversion of AMT to HA and the experimental investigation of the reaction kinetics allowed us to determine the dissociation of CH3SH as the rate-controlling step in the degradation process that culminates in a half-life between 7 and 24 months under typical acid soil conditions of the Brazilian Midwest - region with strong agricultural and livestock vocation. The keto and hydroxy metabolites showed substantial thermodynamic stability and a decrease in toxicity compared to AMT. We hope that this comprehensive study will support the understanding of the degradation of s-triazine-based pesticides.

Exercise Capacity and Biomarkers Among Children and Adolescents With Sickle Cell Disease.

BACKGROUND: Sickle cell disease is the most common genetic hemoglobinopathy globally and systemically affects body functioning, decreasing exercise capacity. OBJECTIVE: To assess exercise capacity through the 6-minute walk test (6MWT) and biomarkers in children and adolescents with sickle cell disease. MATERIALS AND METHODS: Cross-sectional study involving 20 children and adolescents from Brazil. Demographic and socioeconomic data were obtained. Baseline measurements included biomarkers (red blood cells, hemoglobin, hematocrit, white blood cells, platelets, reticulocytes, lactate dehydrogenase, creatine phosphokinase, C-reactive protein, interleukin 6, and fetal hemoglobin). The following data were obtained before, during, and after the 6MWT: heart rate, blood pressure, and peripheral oxygen saturation. RESULTS: Eighteen children and adolescents ages 5-14 years old were analyzed, 61.1% boys, 100% black or brown, and 61.1% in primary education, with low household income. The average distance walked in 6MWT was 463.8 (137.7) m, significantly less than the predicted value (P < .001). The distance of 6MWT was associated positively with age (P = .042) and inversely with reticulocyte count (P = .42) and interleukin 6 (P = .00). Age modified the effect of interleukin 6 in younger children (P = .038). CONCLUSION: Our findings suggest increased baseline levels of biomarkers of hemolysis and inflammation impact on 6MWT performance.

Insights into chalcone analogues with potential as antioxidant additives in diesel-biodiesel blends.

Biodiesel production is one of the promising strategies to reduce diesel consumption and an important contribution to climate change. However, biodiesel stability remains a challenging problem in biofuel use in the global energy matrix. In this context, organic additives have been investigated to minimize these problems and reduce harmful emissions to comply with fuel requirement standards. In this study, we discuss a comprehensive structural description, a behavior of B15 [85% volume of diesel and 15% volume of biodiesel (B100)] stability in the presence of antioxidants (chalcone analogues), and a theoretical calculation to pave the way for clarifying and expanding the potential of title compounds as an antioxidant additive for diesel-biodiesel blends. Finally, a systematic description of the oxidation stability was undertaken using a specialized machine learning computational pySIRC platform.

Assessment of the strength of recommendation and quality of evidence: GRADE checklist. A descriptive study

ABSTRACT BACKGROUND: Grading of Recommendations Assessment, Development and Evaluation (GRADE) is a tool for assessing evidence produced in synthesis reports. OBJECTIVES: To present the translation into Portuguese of the GRADE checklist, whose original version is in English, and to describe and explain each topic, in order to provide examples to researchers and professionals who will use the tool. DESIGN AND SETTING: Descriptive study developed at Centro Universitário Tiradentes, Maceió, Alagoas, Brazil. METHODS: This was a translation of the GRADE checklist, with the addition of the Risk Of Bias In Systematic Reviews (ROBIS) tool in the checklist, with examples of its use. RESULTS: Situations of practical use of the tool were presented in order to facilitate and expand the use of assessment of the quality and strength of evidence among Portuguese speakers. CONCLUSIONS: The GRADE checklist is valuable in helping to assess the strength and quality of evidence for synthesis reports for healthcare decision-making.

Assessment of the strength of recommendation and quality of evidence: GRADE checklist. A descriptive study.

BACKGROUND: Grading of Recommendations Assessment, Development and Evaluation (GRADE) is a tool for assessing evidence produced in synthesis reports. OBJECTIVES: To present the translation into Portuguese of the GRADE checklist, whose original version is in English, and to describe and explain each topic, in order to provide examples to researchers and professionals who will use the tool. DESIGN AND SETTING: Descriptive study developed at Centro Universitário Tiradentes, Maceió, Alagoas, Brazil. METHODS: This was a translation of the GRADE checklist, with the addition of the Risk Of Bias In Systematic Reviews (ROBIS) tool in the checklist, with examples of its use. RESULTS: Situations of practical use of the tool were presented in order to facilitate and expand the use of assessment of the quality and strength of evidence among Portuguese speakers. CONCLUSIONS: The GRADE checklist is valuable in helping to assess the strength and quality of evidence for synthesis reports for healthcare decision-making.

A Blockchain-Based End-to-End Data Protection Model for Personal Health Records Sharing: A Fully Homomorphic Encryption Approach.

Personal health records (PHR) represent health data managed by a specific individual. Traditional solutions rely on centralized architectures to store and distribute PHR, which are more vulnerable to security breaches. To address such problems, distributed network technologies, including blockchain and distributed hash tables (DHT) are used for processing, storing, and sharing health records. Furthermore, fully homomorphic encryption (FHE) is a set of techniques that allows the calculation of encrypted data, which can help to protect personal privacy in data sharing. In this context, we propose an architectural model that applies a DHT technique called the interplanetary protocol file system and blockchain networks to store and distribute data and metadata separately; two new elements, called data steward and shared data vault, are introduced in this regard. These new modules are responsible for segregating responsibilities from health institutions and promoting end-to-end encryption; therefore, a person can manage data encryption and requests for data sharing in addition to restricting access to data for a predefined period. In addition to supporting calculations on encrypted data, our contribution can be summarized as follows: (i) mitigation of risk to personal privacy by reducing the use of unencrypted data, and (ii) improvement of semantic interoperability among health institutions by using distributed networks for standardized PHR. We evaluated performance and storage occupation using a database with 1.3 million COVID-19 registries, which showed that combining FHE with distributed networks could redefine e-health paradigms.

Reply to the 'Comment on "Topography of the Free Energy Landscape on the Claisen-Schmidt Condensation: Solvent and Temperature Effect in the Rate-Controlling Step"' by N. D. Coutinho, H. G. Machado, V. H. Carvalho-Silva and W. A. da Silva, Phys. Chem. Chem. Phys., 2021, 23, 6738.

In the Comment on our paper on the description of the Gibbs Free energy profile of Claisen-Schmidt condensation, it is claimed that our calculations are flawed due to inconsistencies with experimental isotope effects in aqueous acetonitrile. In this Reply, we presented rigorous arguments, ambiguities in the Comment and new calculations confirming the consistency of our results: (i) small differences in the relative energetic barriers in both experimental and theoretical curves make the assignment of the rate-limiting step debatable, making the concept of RCS questionable; (ii) it is shown how the misinterpretation of the elementary steps and of the overall processes rate constants led the Comment to incorrect conclusions about the behavior of the inverse isotopic effect; (iii) neglect in the Comment of the inverse kinetic isotope effect in step R2 due to the hybridization conversion, and of the inverse equilibrium isotopic effect for step R1 to describe an overall iKIE > 1, (iv) an erroneous suggestion in the Comment that the disagreement between experimental kinetic parameters is due to the fact that acetonitrile is not used in previous experimental works, when contradictorily the literature recommends it as being indispensable to allow kinetic accuracy; and (v) new calculations improved by explicit-implicit hybrid treatment again ensure that step R4, and not step R5, can assume the role of RCS in protic solvents. Recognizing that questioning is an excellent path for promoting understanding, we hope that the answers provided here will help to clarify and expand the pertinent topics under discussion.

"pySiRC": Machine Learning Combined with Molecular Fingerprints to Predict the Reaction Rate Constant of the Radical-Based Oxidation Processes of Aqueous Organic Contaminants.

We developed a web application structured in a machine learning and molecular fingerprint algorithm for the automatic calculation of the reaction rate constant of the oxidative processes of organic pollutants by •OH and SO4•- radicals in the aqueous phase-the pySiRC platform. The model development followed the OECD principles: internal and external validation, applicability domain, and mechanistic interpretation. Three machine learning algorithms combined with molecular fingerprints were evaluated, and all the models resulted in high goodness-of-fit for the training set with R2 > 0.931 for the •OH radical and R2 > 0.916 for the SO4•- radical and good predictive capacity for the test set with Rext2 = Qext2 values in the range of 0.639-0.823 and 0.767-0.824 for the •OH and SO4•- radicals. The model was interpreted using the SHAP (SHapley Additive exPlanations) method: the results showed that the model developed made the prediction based on a reasonable understanding of how electron-withdrawing and -donating groups interfere with the reactivity of the •OH and SO4•- radicals. We hope that our models and web interface can stimulate and expand the application and interpretation of kinetic research on contaminants in water treatment units based on advanced oxidative technologies.

Efficiency of water treatment with crushed shell of jatobá-do-cerrado (Hymenaea stigonocarpa) fruit to adsorb Cu(II) and Ni(II) ions: experimental and quantum chemical assessment of the complexation process.

The shell surrounding fruits of the jatobá-do-cerrado tree, in its natural state, was modified by the addition of HNO3 and NaOH and used as an adsorbent in the removal of Cu(II) and Ni(II) from aqueous solutions. The untreated (JIN) and chemically modified (JCT) fruit shell samples were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-ray diffraction. Their efficiency as adsorbents in the removal of Cu(II) and Ni(II) ions from aqueous solutions was studied under different conditions of pH (2-9) and it was observed that the optimal pH for Cu (II) adsorption was 5.5 and for Ni (II) it was 6.0. The adsorption isotherms were obtained at different temperatures (298, 308, 318 K) and the qmax values ranged from 33.96 to 41.00 mg g-1. The adsorbents presented higher selectivity toward Cu ions (II). The thermodynamic analysis results suggest that the adsorption process studied is of a physical nature. Supported by quantum mechanical calculations, the interaction sites of the ion-cellulose and ion-lignin complexes were identified, evidencing the central role of water molecules in stabilization of the complexes. The experimental and theorical results indicate that JIN and JCT have good potential for the adsorption of Cu(II) and Ni(II) ions and are thus promising materials for the removal of other metal ions in aqueous systems.

Integrating multiple blockchains to support distributed personal health records.

Blockchain technologies have evolved in recent years, as have the use of personal health record (PHR) data. Initially, only the financial domain benefited from Blockchain technologies. Due to efficient distribution format and data integrity security, however, these technologies have demonstrated potential in other areas, such as PHR data in the healthcare domain. Applying Blockchain to PHR data faces different challenges than applying it to financial transactions via crypto-currency. To propose and discuss an architectural model of a Blockchain platform named "OmniPHR Multi-Blockchain" to address key challenges associated with geographical distribution of PHR data. We analyzed the current literature to identify critical barriers faced when applying Blockchain technologies to distribute PHR data. We propose an architecture model and describe a prototype developed to evaluate and address these challenges. The OmniPHR Multi-Blockchain architecture yielded promising results for scenarios involving distributed PHR data. The project demonstrated a viable and beneficial alternative for processing geographically distributed PHR data with performance comparable with conventional methods. Blockchain's implementation tools have evolved, but the domain of healthcare still faces many challenges concerning distribution and interoperability. This study empirically demonstrates an alternative architecture that enables the distributed processing of PHR data via Blockchain technologies.

Aqueous picloram degradation by hydroxyl radicals: Unveiling mechanism, kinetics, and ecotoxicity through experimental and theoretical approaches.

Pesticides are chemical compounds widely used to combat pests in crops, and they thus play a key role in agricultural production. However, due to their persistence in aquatic environments, even at low concentrations, their use has been considered an environmental problem and caused concern regarding the adverse effects on human health. This paper reports, for the first time, the mechanisms, kinetics, and an evaluation of the toxicity of picloram degradation initiated by OH radicals in the aqueous environment using quantum chemistry and computational toxicology calculations. The rate constants are calculated using a combination of formulations derived from the Transition State Theory in a realistic temperature range (250-310 K). The results indicate that the two favorable pathways (R1 and R5) of OH -based reactions occur by addition to the pyridine ring. The calculated rate constant at 298 K is compared with the overall second-order reaction rate constant, quantified herein experimentally via the competition kinetics method and data available in the literature showing an excellent agreement. The toxicity assessment and a photolysis study provide important information: i) picloram and the majority of degradation products are estimated as harmful; however, ii) these compounds can suffer photolysis in sunlight. The results of the present study can help understand the mechanism of picloram, also providing important clues regarding risk assessment in aquatic environments as well as novel experimental information.

Topography of the free energy landscape of Claisen-Schmidt condensation: solvent and temperature effects on the rate-controlling step.

Recent studies have found that hydroxide elimination and the C[double bond, length as m-dash]C bond formation step in base-promoted aldol condensation have a strong influence on the overall rate of the reaction, in contrast to the well-accepted first enolization or C-C bond formation step. Here, applying theoretical models to the prototypical reaction of chalcone formation, the complete free energy profile of Claisen-Schmidt condensation is assessed, revealing how a protic solvent and a slight increase in temperature can induce the second enolization as the rate-controlling step (RCS). It is also observed: i) the nonexistence of a step with a much higher energetic barrier than the others, making the concept of RCS debatable; and ii) that the overall inverse kinetic isotopic effect does not exclude second enolization as a RCS in protic continuum medium. We expect that these results can expand the understanding of the decisive role of physicochemical factors on the choose of the RCS in the aldol condensation.

Exercise for cancer cachexia in adults.

BACKGROUND: Cancer cachexia is a multifactorial syndrome characterised by an ongoing loss of skeletal muscle mass, with or without a loss of fat mass, leading to progressive functional impairment. Physical exercise may attenuate cancer cachexia and its impact on patient function. This is the first update of an original Cochrane Review published in Issue 11, 2014, which found no studies to include. OBJECTIVES: To determine the effectiveness, acceptability and safety of exercise, compared with usual care, no treatment or active control, for cancer cachexia in adults. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, and eight other databases to March 2020. We searched for ongoing studies in trial registries, checked reference lists and contacted experts to seek relevant studies. SELECTION CRITERIA: We sought randomised controlled trials in adults with cancer cachexia, that compared a programme of exercise alone or in combination with another intervention, with usual care, no treatment or an active control group. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed titles and abstracts for relevance and extracted data on study design, participants, interventions and outcomes from potentially relevant articles. We used standard methodological procedures expected by Cochrane. Our primary outcome was lean body mass and secondary outcomes were adherence to exercise programme, adverse events, muscle strength and endurance, exercise capacity, fatigue and health-related quality of life. We assessed the certainty of evidence using GRADE and included two Summary of findings tables. MAIN RESULTS: We included four new studies in this update which overall randomised 178 adults with a mean age of 58 (standard deviation (SD) 8.2) years. Study sample size ranged from 20 to 60 participants and in three studies the proportion of men ranged from 52% to 82% (the fourth study was only available in abstract form). Three studies were from Europe: one in the UK and Norway; one in Belgium and one in Germany. The remaining study was in Canada. The types of primary cancer were head and neck (two studies), lung and pancreas (one study), and mixed (one study). We found two comparisons: exercise alone (strength-based exercise) compared to usual care (one study; 20 participants); and exercise (strength-based exercise/endurance exercise) as a component of a multimodal intervention (pharmacological, nutritional or educational (or a combination) interventions) compared with usual care (three studies, 158 participants). Studies had unclear and high risk of bias for most domains. Exercise plus usual care compared with usual care We found one study (20 participants). There was no clear evidence of a difference for lean body mass (8 weeks: MD 6.40 kg, 95% CI -2.30 to 15.10; very low-certainty evidence). For our secondary outcomes, all participants adhered to the exercise programme and no participant reported any adverse event during the study. There were no data for muscle strength and endurance, or maximal and submaximal exercise capacity. There was no clear evidence of a difference for either fatigue (4 to 20 scale, lower score was better) (8 weeks: MD -0.10, 95% CI -4.00 to 3.80; very low-certainty evidence) or health-related quality of life (0 to 104 scale, higher score was better) (8 weeks: MD 4.90, 95% CI -15.10 to 24.90; very low-certainty evidence). Multimodal intervention (exercise plus other interventions) plus usual care compared with usual care We found three studies but outcome data were only available for two studies. There was no clear evidence of a difference for lean body mass (6 weeks: MD 7.89 kg, 95% CI -9.57 to 25.35; 1 study, 44 participants; very low-certainty evidence; 12 weeks: MD -2.00, 95% CI -8.00 to 4.00; one study, 60 participants; very low-certainty evidence). For our secondary outcomes, there were no data reported on adherence to the exercise programme, endurance, or maximal exercise capacity. In one study (44 participants) there was no clear evidence of a difference for adverse events (patient episode report) (6 weeks: risk ratio (RR) 1.18, 95% CI 0.67 to 2.07; very low-certainty evidence). Another study assessed adverse events but reported no data and the third study did not assess this outcome. There was no clear evidence of a difference in muscle strength (6 weeks: MD 3.80 kg, 95% CI -2.87 to 10.47; 1 study, 44 participants; very low-certainty evidence; 12 weeks MD -5.00 kg, 95% CI -14.00 to 4.00; 1 study, 60 participants; very low-certainty evidence), submaximal exercise capacity (6 weeks: MD -16.10 m walked, 95% CI -76.53 to 44.33; 1 study, 44 participants; very low-certainty evidence; 12 weeks: MD -62.60 m walked, 95% CI -145.87 to 20.67; 1 study, 60 participants; very low-certainty evidence), fatigue (0 to 10 scale, lower score better) (6 weeks: MD 0.12, 95% CI -1.00 to 1.24; 1 study, 44 participants; very low-certainty evidence) or health-related quality of life (0 to 104 scale, higher score better) (12 weeks: MD -2.20, 95% CI -13.99 to 9.59; 1 study, 60 participants; very low-certainty evidence). AUTHORS' CONCLUSIONS: The previous review identified no studies. For this update, our conclusions have changed with the inclusion of four studies. However, we are uncertain of the effectiveness, acceptability and safety of exercise for adults with cancer cachexia. Further high-quality randomised controlled trials are still required to test exercise alone or as part of a multimodal intervention to improve people's well-being throughout all phases of cancer care. We assessed the certainty of the body of evidence as very low, downgraded due to serious study limitations, imprecision and indirectness. We have very little confidence in the results and the true effect is likely to be substantially different from these. The findings of at least three more studies (one awaiting classification and two ongoing) are expected in the next review update.

Deciphering the Dynamics of Organic Nanoaggregates with AIEE Effect and Excited States: Lipophilic Benzothiadiazole Derivatives as Selective Cell Imaging Probes.

An aggregation-induced emission enhancement (AIEE) effect in fluorescent lipophilic 2,1,3-benzothiadiazole (BTD) derivatives and their organic nanoaggregates were studied. A set of techniques such as single-crystal X-ray, dynamic light scattering (DLS), electron paramagnetic resonance (EPR), UV-vis, fluorescence, and density functional theory (DFT) calculations have been used to decipher the formation/break (kinetics), properties, and dynamics of the organic nanoaggregates of three BTD small organic molecules. An in-depth study of the excited-state also revealed the preferential relaxation emissive pathways for the BTD derivatives and the dynamics associated with it. The results described herein, for the first time, explain the formation of fluorescent BTD nanoaggregate derivatives and allow for the understanding of their dynamics in solution as well as the ruling forces of both aggregation and break processes along with the involved equilibrium. One of the developed dyes could be used at a nanomolar concentration to selectively stain lipid droplets emitting an intense and bright fluorescence at the red channel. The other two BTDs could also stain lipid droplets at very low concentrations and were visualized preferentially at the blue channel.

Excessive Screen Media Use in Preschoolers Is Associated with Poor Motor Skills.

Excessive screen media use exposure is a robust childhood predictor of sedentary behavior. The association between excessive exposure to sedentary behaviors (e.g., screen media use) and motor skills and how this association differs across sociodemographic strata is an important knowledge gap that needs to be addressed. The study aims to investigate the association of motor skills and screen media use in preschool children, taking into account sociodemographic variables, physical activity, and sleep profile. A cross-sectional survey of 926 children from 27 preschools was performed. The main outcome was defined as motor skills assessed using the general motor quotient (GMQ). Independent variables included sociodemographic variables, screen media use, screen habits, physical activity, and sleep duration. Logistic regression models were used to estimate the associations between the children's motor skills and each exposure factor. More than 55 percent of the children ate while watching television and 28 percent spent a long time watching television, playing video games, or using a computer, tablet, or cell phone. Excessive screen media use increased the risk of a low GMQ by 72 percent and inactivity in children increased the odds by 90 percent; sleep duration at night decreased the odds of a low GMQ by 51 percent and daytime sleep decreased the odds by 33 percent. Excessive screen media use has been associated with poor motor skills and increased physical inactivity in children, especially among those with prolonged exposure. Our findings can alert parents to the consequences of excessive screen media use and can motivate policymakers to encourage sports and other health-promotion strategies.

From the Kinetic Theory of Gases to the Kinetics of Rate Processes: On the Verge of the Thermodynamic and Kinetic Limits.

A variety of current experiments and molecular dynamics computations are expanding our understanding of rate processes occurring in extreme environments, especially at low temperatures, where deviations from linearity of Arrhenius plots are revealed. The thermodynamic behavior of molecular systems is determined at a specific temperature within conditions on large volume and number of particles at a given density (the thermodynamic limit): on the other side, kinetic features are intuitively perceived as defined in a range between the extreme temperatures, which limit the existence of each specific phase. In this paper, extending the statistical mechanics approach due to Fowler and collaborators, ensembles and partition functions are defined to evaluate initial state averages and activation energies involved in the kinetics of rate processes. A key step is delayed access to the thermodynamic limit when conditions on a large volume and number of particles are not fulfilled: the involved mathematical analysis requires consideration of the role of the succession for the exponential function due to Euler, precursor to the Poisson and Boltzmann classical distributions, recently discussed. Arguments are presented to demonstrate that a universal feature emerges: Convex Arrhenius plots (super-Arrhenius behavior) as temperature decreases are amply documented in progressively wider contexts, such as viscosity and glass transitions, biological processes, enzymatic catalysis, plasma catalysis, geochemical fluidity, and chemical reactions involving collective phenomena. The treatment expands the classical Tolman's theorem formulated quantally by Fowler and Guggenheim: the activation energy of processes is related to the averages of microscopic energies. We previously introduced the concept of "transitivity", a function that compactly accounts for the development of heuristic formulas and suggests the search for universal behavior. The velocity distribution function far from the thermodynamic limit is illustrated; the fraction of molecules with energy in excess of a certain threshold for the description of the kinetics of low-temperature transitions and of non-equilibrium reaction rates is derived. Uniform extension beyond the classical case to include quantum tunneling (leading to the concavity of plots, sub-Arrhenius behavior) and to Fermi and Bose statistics has been considered elsewhere. A companion paper presents a computational code permitting applications to a variety of phenomena and provides further examples.

Exercise versus no exercise for the occurrence, severity, and duration of acute respiratory infections.

BACKGROUND: Acute respiratory infections (ARIs) last for less than 30 days and are the most common acute diseases affecting people. Exercise has been shown to improve health generally, but it is uncertain whether exercise may be effective in reducing the occurrence, severity, and duration of ARIs. This is an update of our review published in 2015. OBJECTIVES: To evaluate the effectiveness of exercise for altering the occurrence, severity, or duration of acute respiratory infections. SEARCH METHODS: We searched CENTRAL (2020, Issue 2), MEDLINE (1948 to March week 1, 2020), Embase (1974 to 05 March 2020), CINAHL (1981 to 05 March 2020), LILACS (1982 to 05 March 2020), SPORTDiscus (1985 to 05 March 2020), PEDro (searched 05 March 2020), OTseeker (searched 05 March 2020), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov (searched 05 March 2020). SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs (method of allocation that is not truly random, e.g. based on date of birth, medical record number) of exercise for ARIs in the general population. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data from the included trials using a standard form. One review author entered data, which a second review author checked. We contacted trial authors to request missing data. There were sufficient differences in the populations trialed and in the nature of the interventions to use the random-effects model (which makes fewer assumptions than the fixed-effect model) in the analysis. MAIN RESULTS: We included three new trials for this update (473 participants) for a total of 14 trials involving 1377 adults, published between 1990 and 2018. Nine trials were conducted in the USA, and one each in Brazil, Canada, Portugal, Spain, and Turkey. Sample sizes ranged from 16 to 419 participants, aged from 18 to 85 years. The proportion of female participants ranged from 52% to 100%. Follow-up duration ranged from 1 to 36 weeks (median = 12 weeks). Moderate-intensity aerobic exercise (walking, bicycling, treadmill, or a combination) was evaluated in 11 trials, and was most commonly prescribed at least three times a week for 30 to 45 minutes. There was no difference between exercise and no exercise in the number of ARI episodes per person per year (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.77 to 1.30; 4 trials; 514 participants; low-certainty evidence); proportion of participants who experienced at least one ARI over the study period (RR 0.88, 95% CI 0.72 to 1.08; 5 trials; 520 participants; low-certainty evidence); and the number of symptom days per episode of illness (mean difference (MD) -0.44 day, 95% CI -2.33 to 1.46; 6 trials; 557 participants; low-certainty evidence). Exercise reduced the severity of ARI symptoms measured on the Wisconsin Upper Respiratory Symptom Survey (WURSS-24) (MD -103.57, 95% CI -198.28 to -8.87; 2 trials; 373 participants; moderate-certainty evidence) and the number of symptom days during follow-up period (MD -2.24 days, 95% CI -3.50 to -0.98; 4 trials; 483 participants; low-certainty evidence). Excercise did not have a significant effect on laboratory parameters (blood lymphocytes, salivary secretory immunoglobulin, and neutrophils), quality of life outcomes, cost-effectiveness, and exercise-related injuries. There was no difference in participant dropout between the intervention and control groups. Overall, the certainty of the evidence was low, downgraded mainly due to limitations in study design and implementation, imprecision, and inconsistency. Seven trials were funded by public agencies; five trials did not report funding; and two trials were funded by private companies. AUTHORS' CONCLUSIONS: Exercise did not reduce the number of ARI episodes, proportion of participants experiencing at least one ARI during the study, or the number of symptom days per episode of illness. However, exercise reduced the severity of ARI symptoms (two studies) and the number of symptom days during the study follow-up period (four studies). Small study size, risk of bias, and heterogeneity in the populations studied contributed to the uncertainty of the findings. Larger trials that are designed to avoid risk of bias associated with participant selection, blinding of outcomes assessors, and with adequate reporting of all outcomes proposed for measurement in trials, would help to provide more robust evidence.

Virulence of Streptococcus mutans: An intrafamilial cohort study on transmission of genotypes.

BACKGROUND: The main aims of this cohort study were to measure the intrafamilial risk of transmission, sharing and stability of the most virulent S. mutans genotypes. MATERIAL AND METHODS: A total of 392 clinical isolates of S. mutans obtained from caries-active adults and genotyped to evaluate their transmissibility over time. After extraction of the chromosomal DNA, PCR were performed to detect the genes involved in the production of GbpA (gbpA) and mutacin types I, II, III and IV (mutAI, mutAII, mutAIII and mutAIV). RESULTS: The gbpA, mutAI, mutAII, mutAIII and mutAIV genes were detected in 77.3, 12.5, 51, 16.6 and 89.8% of S. mutans isolates, respectively. The virulence of S. mutans was associated with its transmission (P< 0.01) and stability (P = 0.01), with the most virulent genotypes having higher transmissibility (RR = 1.83, 95% CI 1.44 to 2.32) and higher stability in the oral cavity (RR = 1.52, 95% CI 1.06 to 2.19). CONCLUSIONS: Genotypes with the genetic information to synthesize GbpA and mutacins present an important ecological advantage in the process of colonization by S. mutans; they remain stable among the oral microbiota of the host and favor intrafamilial transmission. Key words:Streptococcus mutans, virulence factors, transmission, dental caries.

Effective/cost effective interventions of child mental health problems in low- and middle-income countries (LAMIC): Systematic review.

BACKGROUND: This systematic review protocol aims to examine the evidence of effectiveness and cost-effectiveness of interventions for children and adolescents with, or at risk of developing mental disorders in low- and middle-income countries (LAMICs). METHODS: We will search Medline Ovid, EMBASE Ovid, PsycINFO Ovid, CINAHL, LILACS, BDENF and IBECS. We will include randomised and non-randomised controlled trials, economic modelling studies and economic evaluations. Participants are 6 to 18 year-old children and adolescents who live in a LAMIC and who present with, or are at high risk of developing, one or more of the conditions: depression, anxiety, behavioural disorders, eating disorders, psychosis, substance abuse, autism and intellectual disabilities as defined by the DSM-V. Interventions which address suicide, self-harm will also be included, if identified during the extraction process. We will include in person or e-health interventions which have some evidence of effectiveness (in relation to clinical and/or functional outcomes) and which have been delivered to young people in LAMICs. We will consider a wide range of delivery channels (e.g., in person, web-based or virtual, phone), different practitioners (healthcare practitioners, teachers, lay health care providers) and sectors (i.e., primary, secondary and tertiary health care, education, guardianship councils). In the pilot of screening procedures, 5% of all references will be screened by two reviewers. Divergences will be resolved by one expert in mental health research. Reviewers will be retrained afterwards to ensure reliability. The remaining 95% will be screened by one reviewer. Covidence web-based tool will be used to perform screening of references and full text paper, and data extraction. RESULTS: The protocol of this systematic review will be disseminated in a peer-reviewed journal and presented at relevant conferences. The results will be presented descriptively and, if possible, meta-analysis will be conducted. Ethical approval is not needed for anonymised secondary data. CONCLUSION: the systematic review could help health specialists and other professionals to identify evidence-based strategies to deal with child and adolescents with mental health conditions.