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Human behavior in cyber space is extremely complex. Change is the only constant as technologies and social contexts evolve rapidly. This leads to new behaviors in cybersecurity, Facebook use, smartphone habits, social networking, and many more. Scientific research in this area is becoming an established field and has already generated a broad range of social impacts. Alongside the four key elements (users, technologies, activities, and effects), the text covers cyber law, business, health, governance, education, and many other fields. Written by international scholars from a wide range of disciplines, this handbook brings all these aspects together in a clear, user-friendly format. After introducing the history and development of the field, each chapter synthesizes the most recent advances in key topics, highlights leading scholars and their major achievements, and identifies core future directions. It is the ideal overview of the field for researchers, scholars, and students alike.
A new nonlinear Schrödinger equation (NLSE) is presented for ocean surface waves. Earlier derivations of NLSEs that describe the evolution of deep-water waves have been limited to a narrow bandwidth, for which the bound waves at second order in wave steepness are described in leading-order approximations. This work generalizes these earlier works to allow for deep-water waves of a broad bandwidth with large directional spreading. The new NLSE permits simple numerical implementations and can be extended in a straightforward manner in order to account for waves on water of finite depth. For the description of second-order waves, this paper proposes a semianalytical approach that can provide accurate and computationally efficient predictions. With a leading-order approximation to the new NLSE, the instability region and energy growth rate of Stokes waves are investigated. Compared with the exact results based on McLean (J. Fluid Mech., vol. 511, 1982, p. 135), predictions by the new NLSE show better agreement than by Trulsen et al. (Phys. Fluids, vol. 12, 2000, pp. 2432–2437). With numerical implementations of the new NLSE, the effects of wave directionality are investigated by examining the evolution of a directionally spread focused wave group. A downward shift of the spectral peak is observed, owing to the asymmetry in the change rate of energy in a more complex manner than that for uniform Stokes waves. Rapid oblique energy transfers near the group at linear focus are observed, likely arising from the instability of uniform Stokes waves appearing in a narrow spectrum subject to oblique sideband disturbances.
The present work was performed to analyze the association of dietary patterns with glycemic control (hemoglobin(Hb)A1c<7%) in a large group of Chinese adults aged between 45 and 59 years.
Habitual dietary intakes in the preceding 12 months were assessed by well-trained interviewers using a validated semi-quantitative food frequency questionnaire(FFQ). Factor analysis with principal component method was used to obtain the dietary patterns, and the associations between dietary patterns and glycemic control were determined using multivariable logistic regression models. Poor glycemic control was defined as HbA1c≥7.0.
Despite decades of research, data on the relationship between dietary patterns and glycemic control(HbA1c<7%) in China are sparse.
A total of 1739 participants aged 45-59 years from Hangzhou were included in the final analysis.
Three dietary patterns were ascertained and labeled as traditional southern Chinese, Western, and grains-vegetables patterns. After controlling of the possible confounders, participants in the highest quartile of Western pattern scores had greater odds ratio(OR) for HbA1c≥7.0(OR=1.05; 95% confidence interval(CI):1.000-1.095; P=0.048) than did those in the lowest quartile. Compared with those in the lowest quartile of grains-vegetables pattern, participants in the highest quartile had lower OR for HbA1c≥7.0(OR=0.82; 95% CI:0.720-0.949; P=0.038). Besides, no significant relationship between the traditional southern Chinese pattern and HbA1c≥7.0 was observed(P>0.05).
This study indicated that the Western pattern was associated with a higher risk, and the grains-vegetables pattern was associated with a lower risk for HbA1c≥7.0. Future prospective studies are needed to confirm our findings.
Existing studies have examined the demand elasticities for organic products only in select categories, and their results for consumers' sensitivity to price changes are inconsistent. Evidence regarding the effects of price promotions on the demand for organic foods vs non-organic foods is scarce. This study aims to (1) examine the own-price elasticities of organic foods vs non-organic counterparts both with and without a promotion in a variety of product categories, and (2) investigate how the distinctive promotion effects between organic and non-organic counterparts depend on food category features. Using purchase data for 36 food categories from the 2015 Nielsen Consumer Panel, we find differential own-price elasticities for organic and non-organic foods, regardless of whether the product is purchased with a promotion. When the products are purchased with a promotion, we find stronger price promotion effects of organic virtues than non-organic virtues and weaker price promotion effects of organic vices than conventional vices. Price promotions of organic foods are more likely to induce health-conscious consumers to switch from conventional purchases to organic purchases in virtues.
This paper investigates the issue of stochastic comparison of multi-active redundancies at the component level versus the system level. Based on the assumption that all components are statistically dependent, in the case of complete matching and nonmatching spares, we present some interesting comparison results in the sense of the hazard rate, reversed hazard rate and likelihood ratio orders, respectively. And we also obtain two comparison results between relative agings of resulting systems at the component level and the system level. Several numerical examples are provided to illustrate the theoretical results.
The modelling of natural convection in porous media is receiving increased interest due to its significance in environmental and engineering problems. State-of-the-art simulations are based on the classic macroscopic Darcy–Oberbeck–Boussinesq (DOB) equations, which are widely accepted to capture the underlying physics of convection in porous media provided the Darcy number, $Da$, is small. In this paper we analyse and extend the recent pore-resolved direct numerical simulations (DNS) of Gasow et al. (J. Fluid Mech, vol. 891, 2020, p. A25) and show that the macroscopic diffusion, which is neglected in DOB, is of the same order (with respect to $Da$) as the buoyancy force and the Darcy drag. Consequently, the macroscopic diffusion must be modelled even if the value of $Da$ is small. We propose a ‘two-length-scale diffusion’ model, in which the effect of the pore scale on the momentum transport is approximated with a macroscopic diffusion term. This term is determined by both the macroscopic length scale and the pore scale. It includes a transport coefficient that solely depends on the pore-scale geometry. Simulations of our model render a more accurate Sherwood number, root mean square (r.m.s.) of the mass concentration and r.m.s. of the velocity than simulations that employ the DOB equations. In particular, we find that the Sherwood number $Sh$ increases with decreasing porosity and with increasing Schmidt number $(Sc)$. In addition, for high values of $Ra$ and high porosities, $Sh$ scales nonlinearly. These trends agree with the DNS, but are not captured in the DOB simulations.
To explore the characteristics of the mitochondrial genome (mitogenome) of the squeaking silkmoths Rhodinia, a genus of wild silkmoths in the family Saturniidae of Lepidoptera, and reveal phylogenetic relationships, the mitogenome of Rhodinia fugax Butler was determined. This wild silkmoth spins a green cocoon that has potential significance in sericulture, and exhibits a unique feature that its larvae can squeak loudly when touched. The mitogenome of R. fugax is a circular molecule of 15,334 bp long and comprises 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and an A + T-rich region, consistent with previous observations of Saturniidae species. The 370-bp A + T-rich region of R. fugax contains no tandem repeat elements and harbors several features common to the Bombycidea insects, but microsatellite AT repeat sequence preceded by the ATTTA motif is not present. Mitogenome-based phylogenetic analysis shows that R. fugax belongs to Attacini, instead of Saturniini. This study presents the first mitogenome for Rhodinia genus.
The commercial Computational Fluid Dynamics (CFD) software STAR-CCM+ was used to simulate the flow and breakup characteristics of a Liquid Jet Injected into the gaseous Crossflow (LJIC) under real engine operating conditions. The reasonable calculation domain geometry and flow boundary conditions were obtained based on a civil aviation engine performance model similar to the Leap-1B engine which was developed using the GasTurb software and the preliminary design results of its low-emission combustor. The Volume of Fluid (VOF) model was applied to simulate the breakup feature of the near field of LJIC. The numerical method was validated and calibrated through comparison with the public test data at atmospheric conditions. The results showed that the numerical method can capture most of the jet breakup structure and predict the jet trajectory with an error not exceeding ±5%. The verified numerical method was applied to simulate the breakup of LJIC at the real engine operating condition. The breakup mode of LJIC was shown to be surface shear breakup at elevated condition. The trajectory of the liquid jet showed good agreement with Ragucci’s empirical correlation.
Parasitoid wasps are key agents for controlling insect pests in integrated pest management programs. Although many studies have revealed that the behavior of parasitic wasps can be influenced by insecticides, the strategies of patch time allocation and oviposition have received less attention. In the present study, we forced the endoparasitoid Meteorus pulchricornis to phoxim exposure at the LC30 and tested the foraging behavior within patches with different densities of the host, the larvae of the tobacco cutworm Spodoptera litura. The results showed that phoxim treatment can significantly increase the patch-leaving tendency of female wasps, while host density had no impact. The number of oviposition and the number of previous patch visits also significantly influenced the patch time allocation decisions. The occurrence of oviposition behavior was negatively affected by phoxim exposure; however, progeny production was similar among patches with different host densities. Phoxim exposure shaped the offspring fitness correlates, including longer durations from cocoon to adult wasps, smaller body size, and shorter longevity. The findings of the present study highlight the sublethal effects that reduce the patch residence time and the fitness of parasitoid offspring, suggesting that the application of phoxim in association with M. pulchricornis should be carefully schemed in agroecosystems.
During technology transitions, incumbents are frequently faced with the ambidextrous challenge of exploiting existing capabilities and exploring new ones. While extant studies focus on radical changes in the product domain, we notice radical changes can happen in both product and market domains. Pioneering studies indicate that cross-functional ambidexterity addresses this challenge at the business-unit level by juxtaposing exploration and exploitation across different functional domains (particularly in product and market domains) and that complementary assets address this challenge at the organizational level. However, how efforts at two levels can be combined to build cross-functional ambidexterity and what roles complementary assets play remain unclear. Therefore, this study conducts an in-depth case study of Huawei Mobile, which managed to achieve superior performance during a technology transition that triggers radical changes in both product and market domains. We find that multi-level synergies contribute to the transition process. Specifically, cross-functional ambidexterity is constructed by prioritizing exploration in the product domain ahead of that in the market domain, and that it generates learning, brand and channel extension, matching, and brand alliance benefits at the business-unit level. Complementary assets help to reduce the uncertainty of exploration and resolve functional conflicts at the organizational level.
Lagenochitina esthonica is a globally distributed chitinozoan in Early to Middle Ordovician rocks. It is regarded as an index species for the early Floian in North America and has a stratigraphically constrained range in other regions. Lagenochitina esthonica is distinguished from other chitinozoans by a distinct flexure, a nearly rounded-square chamber, and a cylindrical neck with a flaring collar. However, since the first description of the species in the 1950s, it has included two varieties: a relatively short form with a test length ~400 μm, and a slender form usually longer than 600 μm. In order to revise the taxonomy of the L. esthonica group, we carried out a statistical morphometric study of a large collection of well-preserved specimens from the Baltic region where the taxon was first established. Additionally, the stratigraphic and geographic distribution of both forms was analyzed based on available occurrence data. The results show that the short form occurs in the upper Tremadocian to lower Dapingian, whereas the slender form is mostly reported from the lower and middle Darriwilian. Both forms are identified on Baltica; the short form has also been reported from Laurentia and South China, whereas the other is known also from Avalonia and Gondwana. The morphological distinction, together with differences in stratigraphic and spatial ranges, suggest that the two forms represent separate species: the original stout L. esthonica, based on the morphology of the holotype, and the slender L. megaesthonica n. sp., described herein. The updated taxonomy enhances the stratigraphic and biogeographic usefulness of lagenochitinids globally.
Nutritional Risk Screening index is a standard tool to assess nutritional risk, but epidemiological data are scarce on Controlling Nutritional Status (CONUT) as a prognostic marker in acute hemorrhagic stroke (AHS). We aimed to explore whether the CONUT may predict a 3-month functional outcome in AHS. In total, 349 Chinese patients with incident AHS were consecutively recruited, and their malnutrition risks were determined using a high CONUT score of ≥ 2. The cohort patients were divided into high-CONUT (≥ 2) and low-CONUT (< 2) groups, and primary outcomes were a poor functional prognosis defined as the modified Rankin Scale (mRS) score of ≥ 3 at post-discharge for 3 months. Odds ratios (OR) with 95% confidence intervals (CI) for the poor functional prognosis at post-discharge were estimated by using a logistic analysis with additional adjustments for unbalanced variables between the high-CONUT and low-CONUT groups. A total of 328 patients (60.4 ± 12.83 years; 66.8% male) completed the mRS assessment at post-discharge for 3 months, with 172 patients at malnutrition risk at admission and 104 patients with a poor prognosis. The levels of total cholesterol and total lymphocyte counts were significantly lower in high-CONUT patients than low-CONUT patients (p = 0.012 and < 0.001, respectively). At 3-month post discharge, there was a greater risk for the poor outcome in the high-CONUT compared with the low-CONUT patients at admission (OR: 2.32, 95% CI: 1.28-4.17). High-CONUT scores independently predict a 3-month poor prognosis in AHS, which helps identify those who need additional nutritional managements.
The effects of early thiamine use on clinical outcomes in critically ill patients with acute kidney injury (AKI) are unclear. The purpose of this study was to investigate the associations between early thiamine administration and clinical outcomes in critically ill patients with AKI.
The data of critically ill patients with AKI within 48 hours after ICU admission were extracted from the Medical Information Mart for Intensive Care III (MIMIC III) database. Propensity score matching (PSM) was used to match patients early receiving thiamine treatment to those not early receiving thiamine treatment. The association between early thiamine use and in-hospital mortality due to AKI was determined using a logistic regression model.
A total of 15,066 AKI patients were eligible for study inclusion. After PSM, 734 pairs of patients who did and did not receive thiamine treatment in the early stage were established. Early thiamine use was associated with lower in-hospital mortality (OR 0.65; 95% CI 0.49-0.87; P < 0.001) and 90-day mortality (OR 0.58; 95% CI 0.45-0.74; P < 0.001), and it was also associated with the recovery of renal function (OR 1.26; 95% CI 1.17-1.36; P < 0.001). In the subgroup analysis, early thiamine administration was associated with lower in-hospital mortality in patients with stage 1 to 2 AKI.
Early thiamine use was associated with improved short-term survival in critically ill patients with AKI. It was possible beneficial role in patients with stage 1 to 2 AKI according to the KDIGO criteria.
To explore the accuracy of estimated 24-h urinary iodine excretion (24-h UIEest) in assessing iodine nutritional status.
Fasting venous blood, 24-h and spot urine samples were collected during the day. The urinary iodine concentration (UIC) and urinary creatinine concentration (UCrC) were measured, and the urinary iodine-to-creatinine ratio (UI/Cr), 24-h UIEest, and 24-h urinary iodine excretion (24-h UIE) were calculated. At the population level, correlation and consistency between UIC, UI/Cr, 24-h UIEest and 24-h UIE were assessed using correlation analysis and Bland–Altman plots. At the individual level, receiver operating characteristic (ROC) curves were used to analyse the accuracy of the above indicators for evaluating insufficient and excessive iodine intake. The reference interval of 24-h UIEest was established based on percentile values.
Indicator can accurately evaluate individual iodine nutrition during pregnancy remains controversial.
Pregnant women (n 788).
Using 24-h UIE as standard, the correlation coefficients of 24-h UIEest from different periods of the day ranged from 0·409 to 0·531, and the relative average differences ranged from 4·4 % to 10·9 %. For diagnosis of insufficient iodine intake, the area under the ROC curve of 24-h UIEest was 0·754, sensitivity and specificity were 79·6 % and 65·4 %, respectively. For diagnosis of excessive iodine intake, the area of 24-h UIEest was 0·771, sensitivity and specificity were 66·7 % and 82·0 %, respectively. The reference interval of 24-h UIEest was 58·43–597·65 μg.
Twenty-four-hour UIEest can better indicate iodine nutritional status at a relatively large sample size in a given population of pregnant women. It can be used for early screening at the individual level to obtain more lead time for pregnant women.
Self-efficacy is a pivotal factor in the etiology and prognosis of major depression. However, longitudinal studies on the relationship between self-efficacy and major depressive disorder (MDD) are scarce. The objectives were to investigate: (1) the associations between self-efficacy and the 1-year and 2-year risks of first onset of MDD and (2) the associations between self-efficacy and the 1-year and 2-year risks of the persistence/recurrence of MDD, in a sample of first-year university students.
We followed 8079 first-year university students for 2 years from April 2018 to October 2020. MDD was ascertained by the Chinese version of the Composite International Diagnostic Interview (CIDI-3.0) based on self-report. Self-efficacy was measured by the 10-item General Self-efficacy (GSE) scale. Random effect logistic regression modeling was used to estimate the associations.
Among participants without a lifetime MDD, the data showed that participants with high baseline GSE scores were associated with a higher risk of first onset of MDD over 2 years [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01–1.08]. Among those with a lifetime MDD, participants with high baseline GSE scores were less likely to have had a MDD over 2 years (OR 0.93, 95% CI 0.88–0.99) compared to others.
A high level of GSE may be protective of the risk of persistent or recurrent MDD. More longitudinal studies in university students are needed to further investigate the impact of GSE on the first onset of MDD.
The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case-control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a 78-item semi-quantitative food frequency questionnaire. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography–tandem mass spectrometry. Multivariate conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic splines (RCS) were plotted to evaluate the dose-response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the ORs of the highest quartile were 0.45 (95%CI: 0.29-0.71, Ptrend = 0.001) for VD dietary intake and 0.26 (95%CI: 0.11-0.60, Ptrend = 0.003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0.02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0.02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women.
Residual negative symptoms and cognitive impairment are common for chronic schizophrenia patients. The aim of this study was to investigate the efficacy of a mindfulness-based intervention (MBI) on negative and cognitive symptoms of schizophrenia patients with residual negative symptoms.
In this 6-week, randomized, single-blind, controlled study, a total of 100 schizophrenia patients with residual negative symptoms were randomly assigned to the MBI or control group. The 6-week MBI group and the control group with general rehabilitation programs maintained their original antipsychotic treatments. The scores for the Positive and Negative Syndrome Scale (PANSS), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and the Symptom Checklist 90 (SCL-90) were recorded at baseline and week 6 to assess psychotic symptoms, cognitive performance, and emotional state, respectively.
Compared with general rehabilitation programs, MBI alleviated the PANSS-negative subscore, general psychopathology subscore, and PANSS total score in schizophrenia patients with residual negative symptoms (F = 33.77, pBonferroni < 0.001; F = 42.01, pBonferroni < 0.001; F = 52.41, pBonferroni < 0.001, respectively). Furthermore, MBI improved RBANS total score and immediate memory subscore (F = 8.80, pBonferroni = 0.024; F = 11.37, pBonferroni = 0.006), as well as SCL-90 total score in schizophrenia patients with residual negative symptoms (F = 18.39, pBonferroni < 0.001).
Our results demonstrate that MBI helps schizophrenia patients with residual negative symptoms improve clinical symptoms including negative symptom, general psychopathology symptom, and cognitive impairment.