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Resistance seam welding additive manufacturing (RSAM) is a new solid-state additive manufacturing technique that utilizes pulsed current and pressure to welding powders layer by layer. In this study, Al1060 powder was employed as the raw material to prepare R0 and R10 samples through RSAM technology and subsequent repeated welding processes, respectively. The results showed that, compared to R0, the grain size of the R10 sample decreased from 34.3 μm to 8.7 μm, and the dislocation density increased from 4.355 × 1014 to 9.436 × 1014 m−2. Additionally, due to the additional heat and pressure from repeated welding, the porosity decreased from 0.998% to 0.017%, the ultimate tensile strength and elongation improved from 63.5 ± 0.5 MPa and 4.5 ± 0.1% in R0 to 93.3 ± 0.5 MPa and 34.3 ± 0.1% in R10. The improvement in mechanical properties is primarily due to the combined effects of grain refinement, dislocation strengthening, and pore self-healing. This study introduces a feasible new approach for additive manufacturing of aluminum alloys and other materials that is difficult to be additively manufactured by other methods.

Tropospheric and ground-level levels of nitrogen dioxide (NO2) may have changed due to environmental policies and technological changes. Here, multiyear ground-based measurement (2014–2022) and satellite-derived retrieval (October 2004 to May 2023) datasets of NO2 concentrations are used to study the long-term ground-level and tropospheric NO2 patterns and trends at four time scales (interannual, quarterly, monthly, and hourly) over the three regions with the highest global NO2 concentrations. Several tropospheric NO2 hotspots are observed over industrialized and highly populated coastal zone areas. Over the past 18 years, these hotpots have generally decreased due to the implementation of strong and effective environmental protection policies. A significant trend reversal was observed in 2011 in East-central China. The maximum values of tropospheric NO2 occurred in winter over East-central China, Western Europe and East-central USA, with concentrations of 13.010, 4.243 and 4.149 × 1015 molecules cm−2, respectively. The Bohai Sea exhibited disproportionately high tropospheric NO2 levels, suggesting it as a significant contributor to regional nitrogen pollution. Ground-level NO2 shows similar temporal patterns to tropospheric concentrations, with over 82.8 % of sites in East-central China exceeding 30 μg m−3, compared to 12.8 % in Western Europe and 3.8 % in East-central USA. The analysis of diurnal variations in ground-level NO2 concentrations shows a significantly decrease during the daytime compared to nighttime, reflecting that the peak occurs at approximately 08:00 and 20:00 LT, while the lowest concentrations at around 12:00 LT. These insights clarify the impacts of environmental policies on NO2 levels and identify critical areas for targeted pollution control, enhancing our understanding of NO2 dynamics in high-pollution regions globally.

ObjectivesThe present study analyzed the impact of the COVID-19 pandemic on the prevalence and incidence of new leprosy cases, as well as the diversity, distribution, and temporal transmission of Mycobacterium leprae strains at the county level in leprae-endemic provinces in Southwest China.MethodsA total of 219 new leprosy cases during two periods, 2018–2019 and 2020–2021, were compared. We genetically characterized 83 clinical isolates of M. leprae in Guizhou using variable number tandem repeats (VNTRs) and single nucleotide polymorphisms (SNPs). The obtained genetic profiles and cluster consequences of M. leprae were compared between the two periods.ResultsThere was an 18.97% decrease in the number of counties and districts reporting cases. Considering the initial months (January–March) of virus emergence, the number of new cases in 2021 increased by 167% compared to 2020. The number of patients with a delay of >12 months before COVID-19 (63.56%) was significantly higher than that during COVID-19 (48.51%). Eighty-one clinical isolates (97.60%) were positive for all 17 VNTR types, whereas two (2.40%) clinical isolates were positive for 16 VNTR types. The (GTA)9, (TA)18, (TTC)21 and (TA)10 loci showed higher polymorphism than the other loci. The VNTR profile of these clinical isolates generated five clusters, among which the counties where the patients were located were adjacent or relatively close to each other. SNP typing revealed that all clinical isolates possessed the single SNP3K.ConclusionCOVID-19 may have a negative/imbalanced impact on the prevention and control measures of leprosy, which could be a considerable fact for official health departments. Isolates formed clusters among counties in Guizhou, indicating that the transmission chain remained during the epidemic and was less influenced by COVID-19 preventative policies.

Low temperatures during the grain-filling phase have a detrimental effect on both the yield and quality of rice grains. However, the specific repercussions of low temperatures during this critical growth stage on grain quality and mineral nutrient composition in high-quality hybrid indica rice varieties have remained largely unexplored. The present study address this knowledge gap by subjecting eight high-quality indica rice varieties to two distinct temperature regimes: low temperature (19°C/15°C, day/night) and control temperature (28°C/22°C) during their grain-filling phase, and a comprehensive analysis of various quality traits, with a particular focus on mineral nutrients and their interrelationships were explored. Exposure of rice plants to low temperatures during early grain filling significantly impacts the physicochemical and nutritional properties. Specifically, low temperature increases the chalkiness rate and chalkiness degree, while decreases starch and amylopectin content, with varying effects on amylose, protein, and gelatinization temperature among rice varieties. Furthermore, crucial parameters like gelatinization enthalpy (ΔH), gelatinization temperature range (R), and peak height index (PHI) all significantly declined in response to low temperature. These detrimental effects extend to rice flour pasting properties, resulting in reduced breakdown, peak, trough, and final viscosities, along with increased setback. Notably, low temperature also had a significant impact on the mineral nutrient contents of brown rice, although the extent of this impact varied among different elements and rice varieties. A positive correlation is observed between brown rice mineral nutrient content and factors such as chalkiness, gelatinization temperature, peak viscosity, and breakdown, while a negative correlation is established with amylose content and setback. Moreover, positive correlations emerge among the mineral nutrient contents themselves, and these relationships are further accentuated in the context of low-temperature conditions. Therefore, enhancing mineral nutrient content and increasing rice plant resistance to chilling stress should be the focus of breeding efforts to improve rice quality.

Accurately assessing future land use/cover change (LUCC) and habitat quality (HQ) is vital for ensuring sustainable use of coastal ecosystem services, but most studies ignore the effects of seawater inundation. This study developed a framework based on the PLUS model and InVEST-HQ model that considers seawater inundation due to sea level rise (SLR) and land subsidence. We used this framework to simulate future LUCC and HQ under different scenarios in the Yellow River Delta (YRD). The results showed: (1) From 1991 to 2020, natural wetlands decreased by 39.87 %, non-wetlands decreased by 3.06 %, and artificial wetlands increased by 730.71 %. The overall HQ showed a decreasing trend, with the largest decrease in non-wetlands. (2) Land subsidence occurred in 93.26 % of the YRD, with a subsidence rate of −36.55 mm/year. Underground brine mining is the most important driving factor. About 6.81 %∼11.16 % of the area will be inundated in 2035, and about 9.39 %∼19.27 % of the area will be inundated in 2050. (3) Future multi-scenario simulations show that the Ecological-Protection scenario can minimize the ecological losses caused by seawater inundation. The simulation of future HQ will be underestimated when seawater inundation is not considered. Our study shows that seawater inundation caused by land subsidence and SLR must be taken into account when simulating LUCC and HQ in coastal areas.

Rice grain yield and quality are negatively impacted by high temperature stress. Irrigation water temperature significantly affects rice growth and development, thus influencing yield and quality. The role of cooler irrigation water in counteracting high temperature induced damages in rice grain yield and quality are not explored. Hence, in the present study two rice hybrids, Liangyoupeijiu (LYPJ) and IIyou 602 (IIY602) were exposed to heat stress and irrigated with water having different temperatures in a split-split plot experimental design. The stress was imposed starting from heading until maturity under field-based heat tents, over two consecutive years. The maximum day temperature inside the heat tents was set at 38 °C. For the irrigation treatments, two different water sources were used including belowground water with cooler water temperature and pond water with relatively higher water temperature. Daytime mean temperatures in the heat tents were increased by 1.2–2.0 °C across two years, while night-time temperature remained similar at both within and outside the heat tents. Cooler belowground water irrigation did have little effect on air temperature at the canopy level but decreased soil temperature (0.2–1.4 °C) especially under control. Heat stress significantly reduced grain yield (33% to 43%), panicles m−2 (9% to 10%), spikelets m−2 (15% to 22%), grain-filling percentage (13% to 26%) and 1000-grain weight (3% to 5%). Heat stress significantly increased chalkiness and protein content and decreased grain length and amylose content. Grain yield was negatively related to air temperature at the canopy level and soil temperature. Whereas grain quality parameters like chalkiness recorded a significantly positive association with both air and soil temperatures. Irrigating with cooler belowground water reduced the negative effect of heat stress on grain yield by 8.8% in LYPJ, while the same effect was not seen in IIY602, indicating cultivar differences in their response to irrigation water temperature. Our findings reveal that irrigating with cooler belowground water would not significantly mitigate yield loss or improve grain quality under realistic field condition. The outcome of this study adds to the scientific knowledge in understanding the interaction between heat stress and irrigation as a mitigation tool. Irrigation water temperature regulation at the rhizosphere was unable to counteract heat stress damages in rice and hence a more integrated management and genetic options at canopy levels should be explored in the future.

Salmonella is a foodborne pathogen that poses a serious threat to both human and animal health and food safety. Flaxseed is rich in unsaturated fatty acids; has anti-metabolic syndrome, anti-inflammatory, and neuroprotective properties; and may be a potential source of feed additives. To investigate the impact of flaxseed on Salmonella-infected laying hens, we administered Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) after adding flaxseed to the feed of laying hens (15% [750 mg/kg]). S. Enteritidis colonization was reduced and its clearance was accelerated from the laying hens. Furthermore, flaxseed supplementation mitigated the damage to the ileum caused by S. Enteritidis. We analyzed alterations in intestinal flora through 16S rRNA amplicon sequencing. S. Enteritidis infection increased the abundance of Akkermansia and triggered the host inflammatory response. Conversely, the addition of flaxseed to the feed increased the abundance of beneficial intestinal bacteria, such as Lactobacilli and Bacteroides. Ovarian health is important for egg production performance in laying hens and our findings indicate that S. Enteritidis can persist in the ovaries for an extended period. Therefore, we further performed transcriptome sequencing analysis of ovarian tissues on day seven after S. Enteritidis infection. S. Enteritidis infection leads to altered ovarian gene expression, including the downregulation of lipid metabolism and growth and development genes and the upregulation of host immune response genes in laying hens. The upregulation of genes associated with growth and development may have stimulated ovarian growth and development.

In recent years, major cities around the world such as New York in UAS, Melbourne in Australia, and Shanghai in China, have planned to boost their nighttime urban vibrancy levels to spur the economy and achieve cultural diversity. The study of nighttime urban vibrancy from the perspective of spatiotemporal characteristics is increasingly being recognized as part of the essential work in the field of urban planning and geography. This research used mobile phone signaling records to measure urban vibrancy in central Shanghai and revealed its spatiotemporal patterns during nighttime. Specifically, this research explored the changes of urban vibrancy within a day, studied the distribution of urban vibrancy during the nighttime, and visually presented the spatiotemporal changes of nighttime urban vibrancy in central Shanghai. Moreover, on the basis of the behavior pattern of each mobile user, we classified nighttime urban vibrancy into three different types: nighttime working vibrancy, nighttime leisure vibrancy, and nighttime floating vibrancy. We then tried to determine how land use affected nighttime leisure vibrancy. The results showed that urban vibrancy in central Shanghai exhibits a periodic pattern over one-day period. A high-level nighttime urban vibrancy belt is present within central Shanghai. Business offices, hotels, entertainment and recreational districts, wholesale markets, and express services contribute most to the vibrancy at nighttime. In addition, the correlation analysis shows that public and commercial facilities generate high levels of nighttime leisure vibrancy than residential facilities. The mixed land use of public and commercial facilities and residential facilities within 500 ​m is more critical than the mixed use of a single land lot. The research can be a basis for supporting land use planning and providing evidence for policy-making to improve the level of nighttime urban vibrancy in cities.

Assessing ecosystem services (ESs) is vital for the environment development. This study explored the variation characteristics of ESs under the restoring vegetation since the Grain for Green Project (GFGP) in Jinghe Watershed, which is a typical watershed experiencing severe soil erosion in the Loess Plateau of China. Herein, the fractional vegetation cover (FVC) is selected as an indicator of the changes in vegetation restoration from 2000 to 2020. Simulations of ESs are based on the Soil and Water Assessment Tool (SWAT), Carnegie Ames-Stanford Approach (CASA) model, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). This paper analyzed the spatiotemporal heterogeneity in vegetation coverage and the response of vegetation coverage to ESs in the Jinghe Watershed with Mann-Kendall test, Pearson correlation coeffificient R and the gray relational analysis (GRA). The results showed that: (1) Since the implementation of the GFGP, the area of forests and grassland has increased significantly. The proportion of vegetation restoration area was 95.15 %; (2) At the whole watershed scale, vegetation restoration and soil conservation (SC), water yied (WY), net primary production (NPP) and habitat quality (HQ) were synergistic relationships, while focusing on the sub-watershed scale, vegetation restoration and SC and HQ were transformed into trade-off relationships in some sub-watershed. (3) Vegetation restoration in the Jinghe Watershed had positive effects on SC, WY, NPP, and HQ. The order of relevance with vegetation restoration was: SC > HQ > NPP > WY, indicating that vegetation restoration in the Jinghe Watershed has the highest closeness to SC. This study showed that since the implementation of the GFGP, vegetation coverage in the Jinghe Watershed has significantly restored, which has promoted the improvement of ESs.

Objectives: Understanding the nature of Mycobacterium leprae transmission is vital to implement better control strategies for leprosy elimination. The present study expands the knowledge of county-level strain diversity, distribution, and transmission patterns of leprosy in endemic provinces of China. Methods: We genetically characterized 290 clinical isolates of M. leprae from four endemic provinces using variable number tandem repeats (VNTR) and single nucleotide polymorphisms (SNPs). Attained genetic profiles and cluster consequences were contrasted with geographical and migration features of leprosy at county levels. Results: Considering the allelic variability of 17 VNTR loci by the discriminatory index, (GTA)9, (AT)17, (AT)15, (TA)18, (TTC)21, and (TA)10 are reported to be more highly polymorphic than other loci. The VNTR profile generated the low-density clustering pattern in the counties of Sichuan and Yunnan, whereas clusters have been observed from the isolates from Huayuan (N = 6), Yongding (N = 3), Zixing (N = 3), Chenxi (N = 2) and Zhongfang (N = 2) counties of Hunan, and Zhijin (N = 3), Anlong (N = 2), Zhenning (N = 2), and Xixiu (N = 2) counties of Guizhou. In some clusters, people’s social relations have been observed between villages. From the 290 clinical isolates, the most predominantly reported SNP was 3K (278, 95.8%), followed by SNP 1D (10, 3.4%), which are typically observed to be predominant in China. We also detected the novel SNP 3J (2, 0.8%), which has not yet been reported in China. Conclusion: The clustering pattern of M. leprae indicates the transmission of leprosy still persists at county levels, suggesting that there is a need to implement better approaches for tracing the close contacts of leprosy patients.

AimsVarious kinds of surgical strategies and prostheses have been advocated to improve short-term and long-term outcomes in type A aortic dissection (TAAD). Large-scale repair of the pathological aorta is hard to generalize due to complex procedures. We aimed to investigate the performance, effectiveness and safety of a novel Sutureless Integrated Stented (SIS) graft prosthesis in TAAD patients undergoing total arch replacement (TAR) and frozen elephant trunk (FET) implantation surgery.MethodsAll patients admitted to Fuwai Hospital were prospectively screened. Urgent or scheduled surgery was arranged for eligible patients. The primary endpoint was operative mortality. Key secondary endpoints included stroke, spinal cord injury, unexpected aortic reoperation, and 1-year survival. Discharged patients were followed up with computed tomography angiography and transthoracic echocardiography at 3 months, 6 months, and 1 year after surgery. Performance, effectiveness and safety analyses were performed in those patients.ResultsBetween August 1 and September 3, 2020, ten TAAD patients were enrolled in this study and successfully implanted with the SIS graft prosthesis. The median (IQR) age was 56.50 (43.75, 66.75) years (range from 31 to 75), and seven patients were male (70.0%). All patients underwent ascending aorta replacement + TAR + FET and additional procedures when necessary. The median (IQR) operation time, cardiopulmonary bypass time and cross clamp time were 270.50 (218.50, 312.50), 110.00 (88.00, 125.75), 69.50 (51.25, 82.75) min, respectively. Of note, the median (IQR) circulatory arrest time was 9.00 (8.00, 9.00) min (range from 4 to 12). The median (IQR) lowest nasopharyngeal temperature was 26.75 (25.98, 27.67) °C. Follow-up was 100% completed. During the 1-year follow-up, no patients died, no severe adverse events occurred, and rate of freedom from aortic reintervention was 100%.ConclusionsThe SIS graft prosthesis was implanted in a novel sutureless way, which simplified the surgical procedure, shortened the circulatory arrest time and avoided deep hypothermia. The preliminary clinical outcomes and follow-up outcomes demonstrated the effectiveness and safety of this prosthesis. A large-scale trial is being conducted to further assess these findings.

Objective: The duration of hypothermic circulatory arrest (HCA) is one of the important factors affecting the prognosis of arch surgery, which is still controversial. The purpose of this study was to investigate the effect of HCA duration on early prognosis in type A aortic dissection (TAAD) patients who underwent arch surgery in our center.Methods: All consecutive patients who underwent surgical treatment for TAAD in Fuwai Hospital from January 2013 to December 2018 were included in this study and divided into four quartile groups based on HCA time. Baseline characteristics, perioperative indicators, and early mortality were statistically analyzed by propensity score matching (PSM) and restricted cubic spline (RCS) method. Perioperative adverse events were confirmed according to the American STS database and Penn classification.Results: About 1,018 consecutive patients (mean age 49.11 ± 1.4 years, male 74.7%) with TAAD treated surgically were eventually included in this study. After PSM, with the prolongation of HCA time, the surgical mortality rates of group [2,15], (15,18], (18,22], and (22,73] were 4.1, 6.6, 7.8, and 10.9% with p = 0.041, respectively. As shown in RCS, the mortality rate increased sharply after the HCA time exceeded 22 min. And from the subgroup analysis, the HCA time of 22 min or less was associated with better clinical outcomes (OR 2.09, 95%CI 1.25–3.45, p = 0.004).Conclusions: The early mortality increases significantly with the duration of HCA time when arch surgery was performed. And multiple systems throughout the body can be adversely affected.

ABSTRACTReports on antimicrobial resistance (AMR) of Mycobacterium leprae, relationship with bacteriological index (BI), and transmission in China are limited. We investigated the emergence of AMR mutations, the relationship between BI and AMR in complete, moderate and lack of BI decline cases, and molecular epidemiological features of AMR cases by enrolling 290 leprosy cases from four endemic provinces. Seven (2.41%), one (0.34%), five (1.72%), one (0.34%), and one (0.34%) strains had single mutations in folP1, rpoC, gyrA, gyrB, and 23S rRNA, respectively. Double mutations in folP1 and gyrA, rpoB and gyrA, and gyrA and 23S rRNA were observed in one (0.34%) strain each. Mutated strains occurred in three out of 81 (95% CI−0.005-0.079, p = 0.083) cases with complete BI decline, in seven out of 103 (95% CI 0.018-0.117, p = 0.008) cases with moderate BI decline, and in four out of 34 (95% CI 0.003-0.231, p = 0.044) cases with lack of BI decline. Most of these mutated strains were geographically separated and diverged genotypically. AMR mutations may not be the main cause of the lack of BI decline. The low transmission of AMR strains at the county level indicates an ongoing transmission at close contact levels.

In recent years, the structure of selenium-enriched polysaccharides and their application in immunomodulation have attracted much attention. In previous studies, we extracted and purified a novel selenium-enriched Pleurotus ostreatus polysaccharide called Se-POP-21, but its structure and immunomodulatory activity were still unclear. In this study, the main structural unit formula of Se-POP-21 was characterized by methylation analysis and an NMR experiment. The results showed that the backbone of Se-POP-21 was →[2,6)-α-D-Galp-(1→6)-α-D-Galp-(1]4→2,4)-β-L-Arap-(1→[2,6)-α-D-Galp-(1→6)-α-D-Galp-(1]4→, branched chain of β-D-Manp-(1→ and β-D-Manp-(1→4)-β-L-Arap-(1→ connected with →2,6)-α-D-Galp-(1→ and →2,4)-β-L-Arap-(1→,respectively, through the O-2 bond. In vitro cell experiments indicated that Se-POP-21 could significantly enhance the proliferation and phagocytosis of RAW264.7 cells, upregulate the expression of costimulatory molecules CD80/CD86, and promote RAW264.7 cells to secrete NO, ROS, TNF-α, IL-1β, and IL-6 by activating the NF-κB protein. The results of this study indicate that Se-POP-21 can effectively activate RAW264.7 cells. Thus, it has the potential to be used in immunomodulatory drugs or functional foods.

Physical activity brings multiple health benefits to seniors. Neighborhood parks provide seniors with accessible spaces and opportunities to engage in physical activity. This study investigated the associations between neighborhood park design characteristics and seniors' total walking step and energy expenditure during the park visit. Seniors' total step was measured by pedometer, and energy expenditure was calculated based on self-reported activities in the park. The study was conducted in 15 neighborhood parks with an area

Artificial intelligence: Algorithm predicts clinical outcomes for hospital inpatients Artificial intelligence outperforms traditional statistical models at predicting a range of clinical outcomes from a patient’s entire raw electronic health record (EHR). A team led by Alvin Rajkomar and Eyal Oren from Google in Mountain View, California, USA, developed a data processing pipeline for transforming EHR files into a standardized format. They then applied deep learning models to data from 216,221 adult patients hospitalized for at least 24 h each at two academic medical centers, and showed that their algorithm could accurately predict risk of mortality, hospital readmission, prolonged hospital stay and discharge diagnosis. In all cases, the method proved more accurate than previously published models. The authors provide a case study to serve as a proof-of-concept of how such an algorithm could be used in routine clinical practice in the future.

Due to better postoperative convalescence and quality of life, experienced centers focus on minimally invasive surgical techniques and approaches, but this approach is not routinely performed for valve-sparing root replacement procedures. The purpose of this study was to assess the safety and feasibility of valve-sparing root replacement via partial upper sternotomy. Between January 2016 and April 2021, 269 patients underwent a valve-sparing root replacement procedure, and partial upper sternotomy was performed in 52 patients. The clinical outcomes of the partial upper sternotomy (PUS) and complete sternotomy (CS) groups, including mortality, degree of aortic insufficiency, blood loss and consumption of blood products, postoperative complications, and hospitalization expenses, were compared. The Kaplan–Meier method was used to assess the degree of aortic regurgitation. Propensity score matching was performed as a sensitivity analysis. There was only one in-hospital death (in the CS group, p = 1) and no postoperative moderate to severe aortic insufficiency in either group. The blood loss and consumption of blood products in the PUS group were also lower than in the CS group, especially for plasma use. Regarding the need for re-exploration because of bleeding, acute kidney injury, pericardial pleural effusion, drainage volume within the first 24 h, mechanical ventilation time, and arrhythmia, the two groups were comparable. Patients in the CS group showed a longer ICU time (74.20 ± 47.21 vs. 50.9 30.16 h, p = 0.001) and higher hospitalization expenses (135,649.52 ± 29,992.21 vs. 123,380.15 ± 27,062.82 yuan, p < 0.001). None of the patients died or reoperated during the follow-up. Freedom from moderate or severe aortic insufficiency remained comparable after matching (p = 0.97). Minimally invasive valve-sparing aortic replacement via partial upper sternotomy can be safely performed in selected patients.

As modern electronics are developed towards miniaturisation, high-degree integration and intelligentisation, a large amount of heat will be generated during the operation of devices. How to efficiently remove needless heat is becoming more and more crucial for the lifetime and performance of electronic devices. Many efforts have been made to improve the thermal conductivity of polymer composites, which is an important component of electronics. Herein, the authors report on preparation of boron nitride micosphere/epoxy composites. The cross-plane thermal conductivity of the resultant composites is up to 1.03 Wm^‒1K^‒1. This is attributed to the thermally conductive network formed by the peeled hexagonal boron nitride flakes. Thanks to the superior thermal stability of boron nitride micosphere, the boron nitride micosphere/epoxy composite shows a decreased coefficient of thermal expansion (53.47 ppm/K) and an increased glass transition temperature (147.2°C) compared with the pure epoxy resin. In addition, the boron nitride micosphere/epoxy composite exhibits a lower dielectric constant compared with that of the hexagonal boron nitride/epoxy composite. This strategy can potentially pave the way for the design and fabrication of materials with high cross-plane thermal conductivity and lower dielectric properties.

With the increasing dedication and sophistication of spammers, email spam is a persistent problem even today. Popular social network sites such as Facebook, Twitter, and Google+ are not exempt from email spam as they all interface with email systems. While some report predicts that email spam business is dying due to the decreasing volume of email spam. Whether email spam business is really dying is an interesting question. In this paper, we analyze email spam trends on Spam Archive dataset, which contains 5.5 million spam emails over 15 years (1998 – 2013). We statistically analyze emails contents including header information (e.g. content type) and embedded items (e.g. URL links). Also, we investigate topic drift using topic modeling technique. Moreover, we perform network analysis on sender-to-receiver IP routing networks. Our study shows the dynamic nature of email spam over one and a half decades and demonstrate that the email spam business is not dying but more capricious.

We have developed a multifunctional thiourea-phosphine catalyzed asymmetric [3 + 2] annulation of Morita–Baylis–Hillman (MBH) carbonates with maleimides, which can efficiently construct functionalized cyclopentenes bearing three contiguous stereocenters in moderate to excellent yields and excellent diastereo- and enantioselectivities. A plausible mechanism has been also proposed on the basis of control experiments and previous literature.

The tidal flat is one of the important components of coastal wetland systems in the Yellow River Delta (YRD). It can stabilize shorelines and protect coastal biodiversity. The erosion risk in tidal flats in coastal wetlands was seldom been studied. Characterizing changes of soil particle size distribution (PSD) is an important way to quantity soil erosion in tidal flats.Based on the fractal scale theory and network analysis, we determined the fractal characterizations (singular fractal dimension and multifractal dimension) soil PSD in a successional series of tidal flats in a coastal wetland in the YRD in eastern China. The results showed that the major soil texture was from silt loam to sandy loam. The values of fractal dimensions, ranging from 2.35 to 2.55, decreased from the low tidal flat to the high tidal flat. We also found that the percent of particles with size ranging between 0.4 and 126 μm was related with fractal dimensions. Tide played a great effort on soil PSD than vegetation by increasing soil organic matter (SOM) content and salinity in the coastal wetland in the YRD.Tidal flats in coastal wetlands in the YRD, especially low tidal flats, are facing the risk of soil erosion. This study will be essential to provide a firm basis for the coast erosion control and assessment, as well as wetland ecosystem restoration.

Background: The association between body mass index (BMI) and rapid eye-movement (REM) sleep-related behavioral disorder (RBD) in Parkinson's disease (PD) remains unknown. Our study was to investigate the association of BMI with RBD in PD patients. Methods: In this cross-sectional study, a total of 1,115 PD participants were enrolled from Parkinson's Progression Markers Initiative (PPMI) database. BMI was calculated as weight divided by height squared. RBD was defined as the RBD questionnaire (RBDSQ) score with the cutoff of 5 or more assessed. Univariable and multivariable logistic regression models were performed to examine the associations between BMI and the prevalence of RBD. Non-linear correlations were explored with use of restricted cubic spline (RCS) analysis. And the inflection point was determined by the two-line piecewise linear models. Results: We identified 426 (38.2%) RBD. The proportion of underweight, normal, overweight and obese was 2.61, 36.59, 40.36, and 20.44%, respectively. In the multivariate logistic regression model with full adjustment for confounding variables, obese individuals had an odds ratio of 1.77 (95% confidence interval: 1.21 to 2.59) with RBD compared with those of normal weight. In the RCS models with three knots, BMI showed a non-linear association with RBD. The turning points of BMI estimated from piecewise linear models were of 28.16 kg/m², 28.10 kg/m², and 28.23 kg/m² derived from univariable and multivariable adjusted logistic regression models. The effect modification by depression on the association between BMI and RBD in PD was also found in this study. Furthermore, the sensitivity analyses linked with cognition, education, and ethnic groups indicated the robustness of our results. Conclusion: The current study found a significant dose-response association between BMI and RBD with a depression-based difference in the impact of BMI on RBD in PD patients. [ABSTRACT FROM AUTHOR]

Biofortification of crops with exogenous iodine is a novel strategy to control iodine deficiency disorders (IDD). The bioaccessibility of iodine (BI) in the biofortified vegetables in the course of soaking, cooking and digestion, were examined. Under hydroponics, the concentration of iodine in leafstalks of the celery and pakchoi increased with increasing exogenous iodine concentration, 54.8-63.9% of the iodine absorbed by pakchoi was stored in the soluble cellular substance. Being soaked in water within 8 h, the iodine loss rate of the biofortified celery was 3.5-10.4% only. More than 80% of the iodine in the biofortified celery was retained after cooking under high temperature. The highest BI of the biofortified vegetables after digestion in simulated gastric and intestinal juice amounted to 74.08 and 68.28%, respectively. Factors influencing BI included pH, digestion duration, and liquid-to-solid ratio. The high BI of the biofortified vegetables provided a sound reference for the promotion of iodine biofortification as a tool to eliminate the IDD.