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Kinetic study of organic reactions, especially multistep catalytic reactions, is crucial to in-depth understanding of reaction mechanisms. Here we report our kinetic study on the chiral disulfonimide-catalyzed cyanosilylation of an aldehyde, which revealed that two molecules of TMSCN are involved in the rate-determining C–C bond-forming step. In addition, the apparent activation energy, enthalpy of activation, and entropy of activation were deduced through a study of the temperature dependence of the reaction rates. More importantly, a novel and efficient method that makes use of the progress rates was developed to treat kinetic data obtained by continuous monitoring of the progress of a reaction by in situ FTIR. [ABSTRACT FROM AUTHOR]

With the aim of efficiently estimating the upper bound of time-dependent failure probability for the time-dependent reliability problem involving random and interval inputs (RI-TDFP), an extended crossing rate method is proposed. The proposed method first converts the time-dependent hybrid reliability analysis into a temporal and spatial multi-parameter problem. Then, it uses the extended crossing rate strategy to estimate the RI-TDFP. The proposed strategy is a single-loop strategy, which is more efficient than the nested double-loop strategies. The proposed method avoids using discretization or optimization strategies to estimate the global minimum of the time-dependent performance function with respect to the time parameter and interval inputs, and thus the computational cost is further reduced. Finally, the proposed method avoids using the first order reliability method (FORM) for reliability analysis with respect to the random inputs, and thus the proposed method is more accurate than the FORM. [ABSTRACT FROM AUTHOR]

When using discontinuous assay of reactions, initial rates are often estimated from a limited number of time points. There has been no detailed study of how best to do this. In this work, time courses were simulated by different theoretical equations (including strong product inhibition, first order, Michaelis–Menten and truly linear), but with random error addition to each data point. Various methods were tested to fit an initial rate to the data, and the result compared with the known "true" value. Fitting a simple quadratic generally gives initial rates as accurate as any other curve, and is better than a linear fit if there are about 8 or more time points. For fewer points a linear fit gives less variable and often more accurate rates. The absolute contribution to data point error has a major impact on rate accuracy, and often dominates that due to curvature, so that sampling to at least 10% conversion is preferred. The accuracy of a linear fit can be improved by methods that reject some later points based on curvature tests. Awareness of these effects can help avoid rate inaccuracies of 10% or more due to poor methods of data analysis. [ABSTRACT FROM AUTHOR]

Aim: It has long been recognized that tropical bird species demonstrate a wide range of traits characteristic for slow life histories, as indicated by lower investment in reproduction, slower senescence or slower physiological pace of life. Nevertheless, evidence for latitudinal variation in avian developmental rates has, so far, been inconclusive and based on limited geographic or phylogenetic sampling. The aim of this study was to test for global associations of avian developmental rates with latitude and migratoriness. Location: Global. Taxon: Birds. Methods: We compiled data on developmental (incubation and fledging) periods of 3,500 passerine and non‐passerine bird species distributed worldwide, which represented nearly all extant avian orders and families. Associations of developmental periods with latitude and migratoriness were analysed with phylogenetically informed comparative models that controlled for major sources of variation in developmental rates (body mass, clutch size, and developmental mode across altricial‐precocial spectrum). Results: Our analyses provided support for a negative latitudinal gradient in the duration of fledging, but not incubation period. After controlling for latitude, we also found that migratory birds showed faster developmental rates than resident species. Finally, we found that developmental rates were nonlinearly associated with clutch size (fastest developmental rates at intermediate clutch size) and that duration of fledging period had higher evolutionary lability than incubation period. Main conclusions: Our global comparative analysis provided convincing and phylogenetically robust evidence for a long‐held hypothesis on latitudinal variation in avian developmental rates, although the pattern was apparent only at the post‐embryonic stage of development (fledging period). This challenges a common belief on longer incubation periods in tropics and indicates that incubation and fledging periods may differently respond to external environmental factors, which can possibly be driven by their different evolutionary lability. The results may contribute to our understanding of biogeographic variation in species diversity. [ABSTRACT FROM AUTHOR]

In the Middle Danube Basin, Quaternary deposits are widely distributed in the Vojvodina region where they cover about 95% of the area. Major research during the last two decades has been focused on loess deposits in the Vojvodina region. During this period, loess in the Vojvodina region has become one of the most important Pleistocene European continental climatic and environmental records. Here we present the dating results of 15 samples taken from the Nosak loess‐palaeosol sequence in northeastern Serbia in order to establish a chronology over the last three glacial–interglacial cycles. We use the pIRIR290 signal of the 4–11 μm polymineral grains. The calculated ages are within the error limits partially consistent with the proposed multi‐millennial chronostratigraphy for Serbian loess. The average mass accumulation rate for the last three glacial–interglacial cycles is 265 g m−2 a−1, which is in agreement with the values of most sites in the Carpathian Basin. Our results indicate a highly variable deposition rate of loess, especially during the MIS 3 and MIS 6 stages, which is contrary to most studies conducted in Serbia where linear sedimentation rates were assumed. [ABSTRACT FROM AUTHOR]

We analyze the rate of convergence of the proximal method of multipliers for non-convex nonlinear programming problems. First, we prove, under the strict complementarity condition, that the rate of convergence of the proximal method of multipliers is linear and the ratio constant is proportional to 1/c when the ratio ‖ (μ 0 , λ 0) − (μ ¯ , λ ¯) ‖ / c is small enough, which implies that the rate of convergence of the proximal method of multipliers is superlinear when the parameter c increases to + ∞. Second, we prove that, without strict complementarity condition, the rate of convergence of the proximal method of multipliers is proportional to 1/c when c exceeds a threshold. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the potential impact of the Pediatric Emergency Care Applied Research Network (PECARN) rules on the CT rate in a large paediatric minor traumatic head injury (MTHI) cohort and compare this with current national Dutch guidelines. This was a planned sub-study of a prospective multicentre observational study that enrolled 1006 children younger than 18 years with MTHI. We calculated the number of recommended CT scans and described trauma-related CT scan abnormalities. The PECARN rules recommended a significantly lower percentage of CT scans in all age categories, namely 101/357 (28.3%) versus 164/357 (45.9%) (p < 0.001) in patients under 2 years of age and 148/623 (23.8%) versus 394/623 (63.2%) (p < 0,001) versus in patients 2 years and older.Conclusion: The projected CT rate can significantly be reduced if the PECARN rules are applied. We therefore advocate that the PECARN guidelines are also implemented in The Netherlands. What is Known: • To guide clinicians whether to perform a CT scan in children with a minor traumatic head injury (MTHI) clinical decision rules has been developed. • The overall CT scan rate in adherence with the Dutch MTHI guidelines is 44%. What is New: • The projected CT rate can significantly be reduced in a Dutch cohort of MTHI if the PECARN rules are applied. • The Dutch national guidelines for MTHI can safely be replaced by the PECARN rules. [ABSTRACT FROM AUTHOR]

The slip rate predicted from geodetic and geomorphological measurements is quite uniform on ~800–1,000 km length of the Altyn Tagh and the Kunlun faults. GPS velocity field documents that tectonic loading on the two active faults changes greatly along their strikes. To explore the mechanical relationship between far‐field tectonic loading and fault slip‐rate accumulation, we built a 3D viscoelastic finite‐element model with fault motion governed by frictional strength of contact interfaces. Based on numerical experiments, it is found that the observed uniform slip rate could reflect lateral variation of frictional strength along fault strike. Variation of predicted frictional coefficient ranges from ~0.13 to ~0.02, verifying that the two active faults must be weak for their mechanical strength. In addition, the good fitness between the relatively weak segment of faults and the location of strong earthquakes suggests that seismic activity along the two faults could be related to their frictional strength. [ABSTRACT FROM AUTHOR]

Transcription bursting creates variation among the individuals of a given population. Bursting emerges as the consequence of turning on and off the transcription process randomly. There are at least three sub-processes involved in the bursting phenomenon with different timescale regimes viz. flipping across the on–off state channels, microscopic transcription elongation events and the mesoscopic transcription dynamics along with the mRNA recycling. We demonstrate that when the flipping dynamics is coupled with the microscopic elongation events, then the distribution of the resultant transcription rates will be over-dispersed. This in turn reflects as the transcription bursting with over-dispersed non-Poisson type distribution of mRNA numbers. We further show that there exist optimum flipping rates (αC, βC) at which the stationary state Fano factor and variance associated with the mRNA numbers attain maxima. These optimum points are connected via α C = β C β C + γ r . Here α is the rate of flipping from the on-state to the off-state, β is the rate of flipping from the off-state to the on-state and γr is the decay rate of mRNA. When α = β = χ with zero rate in the off-state channel, then there exist optimum flipping rates at which the non-stationary Fano factor and variance attain maxima. Here χ C , v ≃ 3 k r + / 2 1 + k r + t (here k r + is the rate of transcription purely through the on-state elongation channel) is the optimum flipping rate at which the variance of mRNA attains a maximum and χ C , κ ≃ 1.72 / t is the optimum flipping rate at which the Fano factor attains a maximum. Close observation of the transcription mechanism reveals that the RNA polymerase performs several rounds of stall-continue type dynamics before generating a complete mRNA. Based on this observation, we model the transcription event as a stochastic trajectory of the transcription machinery across these on–off state elongation channels. Each mRNA transcript follows different trajectory. The total time taken by a given trajectory is the first passage time (FPT). Inverse of this FPT is the resultant transcription rate associated with the particular mRNA. Therefore, the time required to generate a given mRNA transcript will be a random variable. For a stall-continue type dynamics of RNA polymerase, we show that the overall average transcription rate can be expressed as k r ≃ h ∞ + k r + where k r + ≃ λ r + / L , λr+ is the microscopic transcription elongation rate in the on-state channel and L is the length of a complete mRNA transcript and h∞+ = [β/(α + β)] is the stationary state probability of finding the transcription machinery in the on-state channel. [ABSTRACT FROM AUTHOR]

In this paper, we study and simulate the effect of individual social responses, as a collective factor, on the epidemic spreading processes. We formally define the problem based on the traditional S I and S I R compartmental models considering the time-varying infection probability dependent on the social responses. In this study, models of generic and special case scenarios are developed. While in the generic case the effective parameter of behavioral response is demonstrated as one collective factor, in the special case the behavioral response is assumed as the combination of two collective factors: social cost and transfer rate of social awareness. With social cost, we refer to the costs incurred by a certain population to prevent or mitigate an epidemic. With transfer rate of social awareness, we describe the averaged rate of received information and knowledge regarding a disease that individuals hold and make use to avoid negative consequences. We show that, while in both S I and S I R models the density of infected agents grows exponentially during the initial time steps, the inclusion of our models of social responses, either generic or special one, leads to mitigation of the spreading. As a result of both generic and special cases, the density of infected agents in the stationary state and the maximum number of infected agents decrease according to power-law functions for different values of collective factors. In the special case results, we also witnessed significant changes in the slope of decreasing trends of stationary density of states happening for a critical value of transfer rate of social awareness, approximately at about the inverse of the time interval of transmission rate update. With this result, we point out that increasing the transfer rate of social awareness to about this critical point outperforms any slight increase in social cost in reducing the number of infected agents. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to examine the discharging process with insertion of wavy surface and changing shape of nanoparticles. Contours were presented in the form of contours and profiles of energy and temperatures. To get the acceptable accuracy, adaptive grid is employed and time steps for each iteration are variable. The outputs indicate that augmenting A and selection of platelet shape lead to a faster solidification. With augment of A , 14% reduction has been reported for (m = 3). Such percentage augments with the rise of m and 14.03% reduction were reported for (m = 5. 7). At m = 5. 7 , augmenting A from 0.1 to 0.3 makes the time to reduce from 44.16 s to 37.96 s. Lower level of energy was reported for platelet shapes, which means higher liquid fraction of domain. Temperature declines with augment of A and A = 0. 1 prolongs process of about 14.03% in the existence of platelet shape. [ABSTRACT FROM AUTHOR]

The Marginal Value Theorem (MVT) is an integral supplement to Optimal Foraging Theory (OFT) as it seeks to explain an animal's decision of when to leave a patch when food is still available. MVT predicts that a forager capable of depleting a patch, in a habitat where food is patchily distributed, will leave the patch when the intake rate within it decreases to the average intake rate for the habitat. MVT relies on the critical assumption that the feeding rate in the patch will decrease over time. We tested this assumption using feeding data from a population of wild Bornean orangutans (Pongo pygmaeus wurmbii) from Gunung Palung National Park. We hypothesized that the feeding rate within orangutan food patches would decrease over time. Data included feeding bouts from continuous focal follows between 2014 and 2016. We recorded the average feeding rate over each tertile of the bout, as well as the first, midpoint, and last feeding rates collected. We did not find evidence of a decrease between first and last feeding rates (Linear Mixed Effects Model, n = 63), between a mid‐point and last rate (Linear Mixed Effects Model, n = 63), between the tertiles (Linear Mixed Effects Model, n = 63), nor a decrease in feeding rate overall (Linear Mixed Effects Model, n = 146). These findings, thus, do not support the MVT assumption of decreased patch feeding rates over time in this large generalist frugivore. Research Highlights: Wild Bornean orangutan feeding rates do not decrease during a feeding bout.The critical assumption of Marginal Value Theorem, that feeding rates decrease as patch residence, and thus patch depletion, increases, is not upheld in this population of wild Bornean orangutans. [ABSTRACT FROM AUTHOR]

This paper describes radon mass exhalation rate ( J m) and thoron surface exhalation rate ( J s ) of 46 soil samples of district Faridabad, Southern Haryana, India. Scintillation detector based SMART RnDuo (AQTEK System, India) coupled with exhalation chamber was used. Outdoor gamma exposure rate was measured by GM counter based survey meter. J m of one sample and J s of 95% samples were found higher than world average values of 57 mBq kg−1 h−1 and 3600 Bq m−2 h−1 for J m and J s respectively reported by UNSCEAR 2000. No significant correlation was observed between radon/thoron exhalation rates with outdoor gamma exposure rate. [ABSTRACT FROM AUTHOR]

In this paper, the results of ambient dose equivalent rate measurements at different locations are presented. At every location measurements were performed twice a day, in the morning and afternoon. One of the aim of this study was to determine the impact of weather conditions on the ambient dose equivalent rate. Correlation between ambient dose equivalent rate values and the meteorological parameters such as temperature, pressure and relative humidity are analyzed. A moderate positive correlation was found between the ambient dose rate and pressure in the morning measurements. The average annual effective dose is calculated to be 0.105 mSv. [ABSTRACT FROM AUTHOR]

We study a 1-dimensional chain of N weakly anharmonic classical oscillators coupled at its ends to heat baths at different temperatures. Each oscillator is subject to pinning potential and it also interacts with its nearest neighbors. In our set up both potentials are homogeneous and bounded (with N dependent bounds) perturbations of the harmonic ones. We show how a generalised version of Bakry–Emery theory can be adapted to this case of a hypoelliptic generator which is inspired by Baudoin (J Funct Anal 273(7):2275-2291, 2017). By that we prove exponential convergence to non-equilibrium steady state in Wasserstein–Kantorovich distance and in relative entropy with quantitative rates. We estimate the constants in the rate by solving a Lyapunov-type matrix equation and we obtain that the exponential rate, for the homogeneous chain, has order bigger than N - 3 . For the purely harmonic chain the order of the rate is in [ N - 3 , N - 1 ] . This shows that, in this set up, the spectral gap decays at most polynomially with N. [ABSTRACT FROM AUTHOR]

We consider a general monotone regression estimation where we allow for independent and dependent regressors. We propose a modification of the classical isotonic least squares estimator and establish its rate of convergence for the integrated $L^{1}$ -loss function. The methodology captures the shape of the data without assuming additivity or a parametric form for the regression function. Furthermore, the degree of smoothing is chosen automatically and no auxiliary tuning is required for the theoretical analysis. Some simulations and two real data illustrations complement the study of the proposed estimator. [ABSTRACT FROM AUTHOR]

Focusing on the problem that the traditional tracking method is susceptible to occlusion of similar objects, this paper proposed a similarity matching tracking method which based on weighted model. According to weighted theory, it divided the target region into local feature blocks, assigned different weights to them, therefore it established the local weighted model of target. Then it used the target color and location characteristics to calculate the similarity between the test images and the target model. In order to avoid the interference of complex background, the method divided the foreground area before model matching, which could get more accurate matching results. Finally, it proposed a novel method of updating occlusion decision model, which ensured the robustness of the model matching by judging the serious occlusion of the target. The experimental results show that the proposed method can achieve high tracking accuracy by using weighted model and multi-feature similarity matching. And the average center error ( ACE) of this tracker is only 13. 21. The overlap rate is 0. 71. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the forwarding layer interface status was outdated or invalid, this paper proposed a network layer forwarding strategy based on real-time status. Aiming at the information failure phenomenon existing in the adaptive forwarding layer of the content center network, the slow convergence problem and the detection swing problem caused by the SRTI, it enhanced the real-time performance of acquiring network information by improving the periodic detection and triggering top-N detection mechanism in the adaptive forwarding strategy. Theoretical analysis and experimental simulations show that this strategy can effectively reduce the slow convergence time of SRTI and greatly reduce the packet loss rate caused by the detection swing problem. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the influence of the geometric shape on the dissolution rate of the domperidone, a drug model for immediate release dosage form. In this regard, a lack of sufficient information about the effective dissolution rate of the drugs regarding their shapes has made this issue an interesting subject for researchers. Methods: For this purpose, three tablet shapes, namely flat and biconvex both in a round and oblong shapes, with different four sizes were modelled for the preparation of domperidone tablet. In vitro dissolution test was accomplished using a USP dissolution apparatus II. The drug dissolution rate was assessed by calculating various dissolution parameters; e.g., dissolution efficiency (DE), mean dissolution rate (MDR), mean dissolution time (MDT), and difference and similarity factors (f1 and f2). Results: Regarding the disintegration time, the larger tablets showed a faster disintegration time. When the size of the tablets was smaller, the amount of released drug was significantly decreased. In addition, #9 tablets with a flat or biconvex geometry had obvious effects on the DE values. Generally, biconvex tablets had higher DE percentage than the flat tablets. Conclusion: Noticeable differences in dissolution parameters by considering the different geometric shapes play an important role in the drug release kinetics which makes a significant effect on quick onset of action in oral administration. [ABSTRACT FROM AUTHOR]

Consider a rank-ordering problem, ranking a group of subjects by the conditional probability from a Bayesian network (BN) model of binary variables. The conditional probability is the probability that a subject is in a certain state given an outcome of some other variables. The classification is based on the rank order and the class levels are assigned with equal proportions. Two BN models are said to be similar to each other if they are of the same model structure but with different probability distributions each of which satisfies the positive association condition. Let ℳ be a set of BN models which are similar to each other. We constructed a BN model M∗, which is similar to all the models in ℳ and the best with regard to ℳ in the sense of the Kullback-Leibler divergence measure. It is found by numerical experiments that, on average, the agreement rate of classifications between a model in ℳ and the similar model M∗ is far larger than that by a random classification and the difference in agreement rate becomes more apparent as the class number increases. [ABSTRACT FROM AUTHOR]

During the past few decades, response rates have declined across social science research. Although some researchers are willing to accept this state of affairs, in this comment, we argue that low response rates weaken the value of social science research, thereby jeopardizing science research and associated knowledge. We describe the case of a Hong Kong-based multi-site study of addiction treatment seekers to examine approaches to stimulating clinical research and response rates. For this case of addiction treatment seekers, the overall response rate was acceptable (69.7%), despite variation among the three study sites. We discuss factors that likely contributed to this response rate variation to illustrate practical steps that investigators can undertake to improve response rates instead of capitulating to the status quo. [ABSTRACT FROM AUTHOR]

The control performance can be worsened by actuator rate limit, which can result in amplitude attenuation and phase delay in process control. In some extreme situations, actuator rate limit may bring about the system non-convergence. This paper focuses on the control difficulties and solutions of first-order plus time-delay (FOPTD) systems caused by rate limit. The influence of rate limit on stability regions of proportional–integral (PI) controller is analysed. Results show that a small rate limit value can reduce stability regions of PI parameters greatly. The negative correlation between the integral gain and the onset frequency, and the positive correlation between the proportional gain and the onset frequency are conducted. Moreover, the control performance of different PI tuning rules such as Skogestad internal model control, integral gain maximization, delay robustness-constrained optimization and Tyreus–Luyben​ tuning rules is evidently affected by rate limit. Simulation and experiment results verify that the PI controller tuned by Skogestad internal model control (SIMC) method is less sensitive to the rate limit variation and is more suitable for processes (the normalized dead-time is from 0.03 to 1) which have severe actuator rate limit. Tyreus–Luyben tuning rule is another optional method. In addition, the reasons why SIMC is not sensitive to rate limit variation are analysed. These analytical results can offer a guideline for practical applications. • Influence of different parameters on the onset frequency is analysed. • Influence of different PI tuning rules on the closed-loop system is analysed. • SIMC method is less sensitive to the rate limit variation for processes (0. 03 ≤ L ∕ T ≤ 1). • The conclusions are verified by comparative experiments. [ABSTRACT FROM AUTHOR]

To clarify the reinfection profile associated with risk factors of opisthorchiasis, we conducted an epidemiological study on the chemotherapeutic effects on reinfection with O. viverrini in the endemic areas of Northeastern Thailand for 3 years. A total of 3,674 fecal samples were collected from participants in villages of 5 provinces. They were examined microscopically using a modified technique of formalin ethyl-acetate concentration. Egg-positive residents were reexamined year (2018) by year (2019) after treatment with a single dose (40 mg/kg) of praziquantel. Health education was provided to the participants yearly. The egg-positive rate of O. viverrini was 14.3%, and was highest (22.2%) in the 20-30 year-old group in 2017. The egg positive rate was 15.3% in dogs and 11.4% cats. Human reinfection rate was 15.5% and 6.3% in next 2 years, and was highest (23.2%) among the fishermen. Relative risk factors of reinfection were significantly higher for males, over 40-year-old age, or working as fishermen or farmers, and eating uncooked fish within the preceding year. A significant difference resulting from a health education program was observed in the third year. Therefore, health education and sustainable surveillance for opisthorchiasis should be maintained to decrease the risk of reinfection. [ABSTRACT FROM AUTHOR]

PurposeNomograms are tools used in clinical practice to predict cancer outcomes and to help make decisions regarding management of disease. Since its conception, utility of the prostate cancer nomogram has more than tripled. Limited information is available on the relation between the nomograms' predicted probabilities and obesity. The purpose of this study was to examine whether the predictions from a validated postoperative prostate cancer nomogram were associated with obesity.MethodsWe carried out a cross-sectional analysis of 1220 patients who underwent radical prostatectomy (RP) in southern California from 2000 to 2008. Progression-free probabilities (PFPs) were ascertained from the 10-year Kattan postoperative nomogram. Multivariable logistic regression models estimated odds ratios (ORs) and 95% confidence intervals (CIs).ResultsIn the present study, aggressive prostate cancer (Gleason ≥7), but not advanced stage, was associated with obesity (p = 0.01). After adjusting for age, black race, family history of prostate cancer and current smoking, an inverse association was observed for 10-year progression-free predictions (OR = 0.50; 95% CI = 0.28–0.90) and positive associations were observed for preoperative PSA levels (OR = 1.23; 95% CI = 1.01–1.50) and Gleason >7 (OR = 1.45; 95% CI = 1.11–1.90).ConclusionObese RP patients were more likely to have lower PFP values than non-obese patients, suggesting a higher risk of experiencing prostate cancer progression. Identifying men with potentially higher risks due to obesity may improve disease prognosis and treatment decision-making.

Background: Studies report varying rates and predictors of mild cognitive impairment (MCI) progression and reversion. Methods: We determined MCI reversion and progression among 473 community-living adults aged ≥55 years in the Singapore Longitudinal Ageing Study with an average of 6 years of follow-up and estimated association with baseline variables. Results: A total of 208 MCI participants reverted to normal cognition (44.0%) and 19 progressed to dementia (4.0%). In a model adjusted for age, gender, education, ethnicity, cardiovascular risk factors/diseases, APOE ε4 status, depressive symptoms, leisure-time activities (LTA), and baseline Mini-Mental State Examination (MMSE), we found that LTA score (OR = 1.07, 95% CI 1.02–1.13), MMSE score (OR = 1.21, 95% CI 1.11–1.31), and subjective memory complaint (OR = 1.83, 95% CI 1.16–2.90) significantly predicted MCI reversion. Controlling for all variables, age (OR = 1.09, 95% CI 1.02–1.17), lower education (OR = 3.26, 95% CI 1.01–10.49), and the metabolic syndrome (OR = 3.13, 95% CI 1.12–8.77) significantly predicted MCI progression. Controlling for age, sex, ethnicity, and education, diabetes significantly predicted MCI progression (OR = 3.19, 95% CI 1.23–8.26), but the presence of other cardiometabolic factors reduced this association to an OR of 2.18 (95% CI 0.72–6.60). Conclusion: In this relatively younger population, there were higher rates of MCI reversion and lower rates of MCI progression which were predicted by the positive effects of LTA and a higher MMSE score as well as by the deleterious effect of the metabolic syndrome and diabetes.

Abstract Background Unplanned returns to hospital are common, costly, and potentially avoidable. We aimed to investigate and characterize reasons for all-cause readmissions to hospital as in-patients (IPs) and visits to the Emergency Department (ED) within 30-days following patient discharge post head and neck surgery (HNS). Methods Retrospective case series with chart review. All patients within the Department of Otolaryngology – Head and Neck Surgery who underwent HNS for benign and malignant disease from January 1, 2010 to May 31, 2015 were identified. The electronic medical records of readmitted patients were reviewed for reasons of readmission, demographic data, and comorbidities. Results Following 1281 surgical cases, there were 41 (3.20%) IP readmissions and 109 (8.43%) ED visits within 30-days after discharge for HNS. For IP readmissions, most common causes included infection (26.8%), respiratory symptoms (17.1%), and pain (17.1%). Most common reasons for ED visits were for pain (31.5%), bleeding (17.6%), and infection (14.8%). Readmitted IPs had significantly higher health burden at pre-operative baseline as compared to patients who visited the ED when assessed with the American Society of Anesthesiology scores (p = 0.002) and the Cumulative Illness Rating Scale (p = 0.004). Conclusion Rate of 30-day IP readmission and ED utilization was 3.20 and 8.43%, respectively. Pain and infection were common causes for returns to hospital. Discharge planning may be improved to target common causes for post-surgical hospital visits in order to decrease readmission rates.

Tariff policy outline and the formation of prices for services in freight transport currently lie in the competencies of individual carriers. Price formation in freight transport is fully liberalized and it has contributed mainly to a fair competition and a more effective acquisition activity of railway undertakings. In EU countries, tariffs in railway freight transport are still important today and are applicable in the form of commercial tariffs for individual railway carriers. The aim of this paper is to propose a methodology for the tariff formation in railway freight transport, taking into account the specific technical and technological requirements for transport and costs. The proposed methodology represents the scientific procedures for the efficient design of tariffs for rail freight. The scientific methods used in the methodology are focused on demand analysis, identification of the vehicle fleet, determination of employees, technology of individual shipments, cost calculation and calculation of rates, establishment of price-lists and setting the price of transportation.

Given X ∈ R p and Y ∈ R two random variables, assume the model Y = ψ (X) + ε where ψ (·) is an unknown function and ε is a random error. We estimate the conditional covariance matrix Cov (E [ X | Y ]) applying a plug-in kernel-based algorithm to its entries. Next, we investigate the estimators rate of convergence under smoothness hypotheses on the density function of (X , Y). In a high-dimensional context, we improve the consistency the whole matrix estimator by providing a decreasing structure over the Cov (E [ X | Y ]) entries. We illustrate a sliced inverse regression setting with a simulation study. [ABSTRACT FROM AUTHOR]

The population-level case-fatality rate (CFR) associated with COVID-19 varies substantially, both across countries at any given time and within countries over time. We analyze the contribution of two key determinants of the variation in the observed CFR: the age-structure of diagnosed infection cases and age-specific case-fatality rates. We use data on diagnosed COVID-19 cases and death counts attributable to COVID-19 by age for China, Germany, Italy, South Korea, Spain, the United States, and New York City. We calculate the CFR for each population at the latest data point and also for Italy, Germany, Spain, and New York City over time. We use demographic decomposition to break the difference between CFRs into unique contributions arising from the age-structure of confirmed cases and the age-specific case-fatality. In late June 2020, CFRs varied from 2.2% in South Korea to 14.0% in Italy. The age-structure of detected cases often explains more than two-thirds of cross-country variation in the CFR. In Italy, the CFR increased from 4.2% to 14.0% between March 9 and June 30, 2020, and more than 90% of the change was due to increasing age-specific case-fatality rates. The importance of the age-structure of confirmed cases likely reflects several factors, including different testing regimes and differences in transmission trajectories; while increasing age-specific case-fatality rates in Italy could indicate other factors, such as the worsening health outcomes of those infected with COVID-19. Our findings lend support to recommendations for data to be disaggregated by age, and potentially other variables, to facilitate a better understanding of population-level differences in CFRs. They also show the need for well-designed seroprevalence studies to ascertain the extent to which differences in testing regimes drive differences in the age-structure of detected cases. [ABSTRACT FROM AUTHOR]

In this paper, we are interested in the decay properties of the axisymmetric solutions to the stationary Navier-Stokes equations in R 3 with finite Dirichlet integral. We establish some new a priori decay rates for the second order derivatives of the velocity. The result is obtained by combining the weighted energy estimates, the Brezis-Galleout inequality and the scaling argument. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to study the effect of flow rate (0.42∼2.09 m/s) on the corrosion behavior of WB36CN1 steel pipe in the simulated secondary circuit water environment (170°C, 6 mg/L ethanolamine + 100 µg/L NaCl), for which an autoclave was used to simulate the secondary circuit environment for carrying out related experiments. Design/methodology/approach: The corrosion behaviors were studied by electrochemical methods, morphological observations and elemental analysis. Findings: As flow rate increases, the amplitude of the current noise fluctuates increased, noise resistance Rn and spectral noise resistance Rsn decreased, the shear stress on the surface of WB36CN1 steel increases, the oxygen content on the surface decreases, the roughness becomes smaller. Meanwhile, the energy of energy distribution plot is concentrated at high frequencies under the three flow conditions, the slopes of current power spectral density curve approach 0 db/decade. This means that the oxide on the surface becomes less and corrosion rate increases with increasing flow rate. The corrosion type of WB36CN1 steel was uniform corrosion; the degree of uniform corrosion is higher at high flow rate. Originality/value: The effect of flow rate on the corrosion behavior of WB36CN1 steel pipe in the secondary circuit water environment was studied by using electrochemical methods in the laboratory. The effect mechanism of flow rate for corrosion behavior was obtained. [ABSTRACT FROM AUTHOR]

Background: Delirium in advanced cancer inpatient ranges between 13% and 85%. Reasons for this variability on the reported data could be related to the setting where they are admitted. Methods: This is an observational, comparative, prospective study on delirium diagnosis and delirium course of advanced cancer inpatients in two different palliative care settings. Hospice (C1) versus palliative care supportive team (C2). Differences between delirium precipitants, delirium treatment, and delirium survival were observed. Results: From 582 consecutive admissions, 494 from C1 and 88 from C2, finally 227 patients met inclusion criteria, were entered in the study. Total population delirium rate at admission, if we add both centers, was 57 patients (25%), 46 (26%) from C1 and 11 (22%) from C2; no statistically significant differences between delirium rate at admission between the two centers were found (χ2). When delirium course between delirious patients admitted in C1 and C2 was analyzed, a significantly higher rate of delirium reversibility was found in C2 [11/14 (78%)] versus [9/65 (14%)] in C1 (χ2p ≤ 0.001). Conclusion: The frequency of delirium at admission and during the hospitalization in advanced cancer patients does not seem to be related to the setting, what seems to be related is the delirium course. [ABSTRACT FROM AUTHOR]

In an IEEE 802.11 Distributed Coordination Function–based wireless network with multiple hops, a node operates on its own with several predefined data rates (i.e. following modulation and coding schemes). Moreover, the IEEE 802.11 Distributed Coordination Function node's communication is characterized by transmission and carrier-sensing distances. The transmission one is, in general, reverse proportional to the data rate. Meanwhile, the carrier distance keeps constant regardless of the modulation and coding scheme. Therefore, when a node has a high transmission rate, within its carrier-sensing range, the number of nodes may increase. The previous works have not yet extensively investigated the impact of data rates on such a scenario. This article addresses that issue aiming to quantify the network performance of the multi-hop IEEE 802.11 networks. As a solution, we propose the mathematical expressions, which consider data rates, for end-to-end throughputs, as well as delays in the network with string topology. We confirm the expressions' correctness by presenting the quantitative agreements between the analytical and simulation results. [ABSTRACT FROM AUTHOR]

Background: Colonoscopies are effective means of detecting and removing precancerous adenomatous polyps. The adenoma detection rate (ADR) is a marker of colonoscopy quality and an independent predictor of colorectal cancer incidence. Focused training interventions may improve an endoscopist's ADR, but the supporting research is limited. This systematic review and meta-analysis identified, critically appraised, and meta-analyzed data from randomized trials (RCTs) evaluating the effect of training interventions on ADRs.Methods: Ovid Medline, EMBASE, CENTRAL, Eric, CINAHL, Scopus, Web of Science, and ClinicalTrials.gov were searched for RCTs investigating the effect of an educational intervention on ADRs. Two reviewers independently screened, identified, and extracted trial-level data. Internal validity was assessed in duplicate using the Risk of Bias tool. Our primary outcome was the ADR. Secondary outcomes were advanced ADR, adenocarcinoma detection rate, polyp detection rate, and withdrawal times. Safety outcomes were post-polypectomy bleeding rate and colonoscopy-related perforation rate.Results: From 2837 screened citations, we identified 3 trials (119 endoscopists) meeting our inclusion criteria. Training interventions were associated with a trend toward increased ADRs (odds ratio 1.16, 95% confidence interval (CI) 1.00-1.34; I2 83%; 3 trials; 119 endoscopists). When limited to screening colonoscopies, the odds ratio for ADRs associated with training interventions was 1.17 (95% CI 1.00-1.36; I2 80%; 3 trials; 119 endoscopists). There was a high level of heterogeneity between the trials' training interventions. Training intervention improved the advanced ADR, adenocarcinoma detection rate, polyp detection rate, and withdrawal times. Safety outcomes were not reported.Conclusions: A focused training intervention was associated with a strong trend toward increased ADRs among certified endoscopists. While the described training interventions definitely show promise, further efforts around continuing professional developments activities are needed to more consistently improve ADRS among certified endoscopists. [ABSTRACT FROM AUTHOR]

We consider the time decay rates of smooth solutions to the Cauchy problem for the compressible Navier-Stokes system with and without a Yukawa- type potential. We prove the existence and uniqueness of global solutions by the standard energy method under small initial data assumptions. Further- more, if the initial data belong to L¹(R³), we establish the optimal time decay rates of the solution as well as its higher-order spatial derivatives. In particu- lar, we obtain the optimal decay rates of the highest-order spatial derivatives of the velocity. Finally, we derive the lower bound time decay rates for the solution and its spacial derivatives. [ABSTRACT FROM AUTHOR]

We give a rational approximation to Euler's constant at a geometric rate of convergence, which is easy to compute. Moreover, such an approximation is completely monotonic. The approximants are built up in terms of expectations of the harmonic numbers acting on the standard Poisson process. [ABSTRACT FROM AUTHOR]

A growing body of evidence suggests that mutation rates exhibit intra-species specific variation. We estimated genome-wide loss of heterozygosity (LOH), gross chromosomal changes, and single nucleotide mutation rates to determine intra-species specific differences in hybrid and homozygous strains of Saccharomyces cerevisiae. The mutation accumulation lines of the S. cerevisiae hybrid backgrounds - S288c/YJM789 (S/Y) and S288c/RM11-1a (S/R) were analyzed along with the homozygous diploids RM11, S288c, and YJM145. LOH was extensive in both S/Y and S/R hybrid backgrounds. The S/Y background also showed longer LOH tracts, gross chromosomal changes, and aneuploidy. Short copy number aberrations were observed in the S/R background. LOH data from the S/Y and S/R hybrids were used to construct a LOH map for S288c to identify hotspots. Further, we observe up to a sixfold difference in single nucleotide mutation rates among the S. cerevisiae S/Y and S/R genetic backgrounds. Our results demonstrate LOH is common during mitotic divisions in S. cerevisiae hybrids and also highlight genome-wide differences in LOH patterns and rates of single nucleotide mutations between commonly used S. cerevisiae hybrid genetic backgrounds. [ABSTRACT FROM AUTHOR]

Background: Treatment of palmar and axillary primary focal hyperhidrosis (PFH) in children up to 16 years using thoracoscopic sympathicotomy is supported by scarce evidence. Therefore, this study aimed to summarize the results of our standardized bilateral, one‐stage, single‐port sympathicotomy (BOSS) in children up to 16 years of age. Methods: Consecutive children (n = 14) up to 16 years of age undergoing BOSS between October 2011 and June 2015 in our institution were included in this retrospective study. Results: Recurrence of primary hyperhidrosis was noted in seven patients (50.0%), of whom five patients (35.7%) underwent reoperation. Reoperations were associated with placement of additional thoracoscopic ports (n = 1; 12.5%), intraoperative placement of pleural drains (n = 2; 25%), and prolonged air leak (n = 1; 12.5%). Despite the high recurrence and reoperation rates, overall patient satisfaction was high with a median satisfaction score of 7.5 (interquartile range of 1.75; range: 4‐9). Conclusion: Although the overall patient satisfaction score in our cohort was good, BOSS for the treatment of intolerable palmar and axillary PFH in children up to 16 years of age is associated with a high recurrence and reoperation rate. [ABSTRACT FROM AUTHOR]