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Plastic injection molding technology is one of the important technologies for the manufacturing industry. In this paper, a numerical dynamic injection molding technology (DIMT) is presented, which is based on the finite element (FE) method. This numerical simulation method introduces a vibrational force into the conventional injection molding technology (CIMT). Some meaningful work has been executed for investigating the mechanical evolution behavior of DIMT. As the basis for illustrating the mechanism in warpage optimization results, dynamic parameter analysis on the rule of pressure response is performed in detail. In the warpage optimization work, three kinds of structure with different molding materials are selected as the comparison. The final warpage of each product is efficiently minimized by using a Gaussian process-based sequential optimization method. From the further discussions, the features of DIMT in improving the molding quality are revealed, indicating that it may not be appropriate for geometrically large structures. This study has significant meaning for the actual injection molding industry.

Shale gas plays a crucial role in the national energy supply. However, fast pressure drop, production decline, and water resources pollution caused by well interference and fracture hits become more severe in multi‐layer mining shale gas fields. Such as, it is urgent to evaluate the interference of multi‐stage fracturing horizontal wells (MFHWs) between the upper and lower gas layers in Chinese Jiaoshiba shale gas field. Therefore, we put forward a comprehensive method to analyze the MFHW interference in this paper. The method contains bottom‐hole pressure response analysis (BHPRA) during neighboring well fracturing, BHPRA of well interference test, and production dynamic analysis. Our study indicates that longitudinal pressure interference exists between the Jiaoshiba upper and lower gas layers upon the apparent interference pressure response in a multi‐well test. However, MFHW interferences occur in the corresponding fracturing stages with shorter distance, and the interference strength is related to both well distance and fracturing scales. The Jiaoshiba upper gas layers can be developed to increase the gas production performance, but it is necessary to maintain a reasonable well spacing to avoid severe interference during the development. We put forward a comprehensive method to analyze the MFHWs interference in this paper. The method contains bottom‐hole pressure response analysis (BHPRA) during neighboring well fracturing, BHPRA of well interference test, and production dynamic analysis. Our study indicates that longitudinal pressure interference exists between the Jiaoshiba upper and lower gas layers upon the apparent interference pressure response in a multi‐well test.

This chapter contains sections titled: Introduction Coupled and Uncoupled Solutions Uncoupled Undrained Loading Derivation of Pore Pressure Parameters Drained and Undrained Loading Solutions of Pore Pressure Equations and Comparisons with Experimental Results Rheological Model to Represent Relative Compressibilities of Unsaturated Soil

Evapotranspiration (ET), a crucial component of water consumption in the hydrological process, is directly controlled by soil moisture (SM) and vapor pressure deficit (VPD) from the perspectives of water supply and demand. However, SM and VPD are strongly coupled through multiple physical processes, confounding their effects on ET. Here, we decouple the interaction between SM and VPD and then analyze the spatiotemporal pattern of their individual effects on ET based on multiple observation‐based data sets. The results show that ET is limited by SM rather than VPD in approximately 63% of global land areas (60°S–60°N), defined as water supply‐limited regions. From 1982 to 2014, the effect of SM on ET enhances significantly in 43% of the water supply‐limited regions. The trends can be attributed to changes in SM and VPD themselves as well as to changes in vegetation conditions. Using the findings from the observation‐based data sets as the benchmark, we show that Earth System Models (ESMs) can overall reproduce the spatial pattern of SM and VPD effects on ET but fail to capture their temporal trends. Our results highlight that the water supply and demand control on ET varies with changing environments, which should be explicitly considered when analyzing the terrestrial water cycle and land‐atmosphere interaction. Plain Language Summary Evapotranspiration (ET) plays a crucial role in the global water cycle and is directly affected by water supply (e.g., soil moisture, SM) and atmospheric evaporative demand (e.g., vapor pressure deficit, VPD). In this study, we disentangle the effects of SM and VPD on ET and analyze their spatiotemporal patterns using multiple observation‐based data and Earth System Models (ESMs). Our findings suggest that the significant increasing trend in SM control on ET is widespread in water supply‐limited regions from 1982 to 2014. However, ESMs can not reproduce the trends derived from observation‐based data. Our research enhances the understanding of how ET responds to water supply and demand in a changing environment, aiding in predicting water resource availability. This work also underscores the need to improve the capability of ESMs to better simulate the dynamic response of ET to its influencing factors. Key Points The controls of water supply (soil moisture, SM) and water demand (vapor pressure deficit, VPD) on evapotranspiration (ET) are disentangled A significant increase in the effect of SM on ET is observed in 43% of water supply‐limited regions Earth System Models cannot capture the trends of SM and VPD effects on ET

Barley (Hordeum vulgare) is more drought tolerant than other cereals, thus making it an excellent model for the study of the chemical, transcriptomic and physiological effects of water deficit. Roots are the first organ to sense soil water deficit. Therefore, we studied the response of barley seminal roots to different water potentials induced by polyethylene glycol (PEG) 8000. We investigated changes in anatomical parameters by histochemistry and microscopy, quantitative and qualitative changes in suberin composition by analytical chemistry, transcript changes by RNA-sequencing (RNA-Seq), and the radial water and solute movement of roots using a root pressure probe. In response to osmotic stress, genes in the suberin biosynthesis pathway were upregulated that correlated with increased suberin amounts in the endodermis and an overall reduction in hydraulic conductivity (Lpr). In parallel, transcriptomic data indicated no or only weak effects of osmotic stress on aquaporin expression. These results indicate that osmotic stress enhances cell wall suberization and markedly reduces Lpr of the apoplastic pathway, whereas Lpr of the cell-to-cell pathway is not altered. Thus, the sealed apoplast markedly reduces the uncontrolled backflow of water from the root to the medium, whilst keeping constant water flow through the highly regulated cell-to-cell path.

In the present study, pond ash from Panki thermal power plant, India (seismic zone III), has been reinforced with geogrid layers and the influence of reinforcement on dynamic shear modulus, material damping ratio, degradation index and resistance to liquefaction of pond ash samples has been investigated. The static and dynamic properties of ash samples without and with geogrid reinforcement have been determined by laboratory experiments. Further, these properties have been used in the dynamic response analysis of the two-dimensional domain of the Panki pond ash deposit that is pond ash column reinforced without and with geogrid. The OpenSees (Open System for earthquake engineering simulation) software is used to perform the analysis. Three moderate magnitude earthquakes (Chamba, Chamoli and Uttarkashi) of Himalayan origin have been considered to study the variations of acceleration, displacement and excess pore water pressure ratio with time for different layers of pond ash columns without and with geogrid reinforcement. Cyclic triaxial experiments show that due to the provision of geogrid reinforcement, the dynamic shear modulus increases about 13% to 81.6% and the liquefaction resistance increases about 91–162%. The dynamic response analysis shows that for geogrid-reinforced pond ash column, the peak ground acceleration (PGA) value decreases about 32–33%, 17–22% and 13.5–18% and the peak ground displacement (PGD) value decreases about 23.5–39%, 18.5–20% and 13–17% as compared to unreinforced pond ash column for Chamba, Chamoli and Uttarkashi earthquakes, respectively.

AbstractObjectiveTo examine the dose-response relation between reduction in dietary sodium and blood pressure change and to explore the impact of intervention duration.DesignSystematic review and meta-analysis following PRISMA guidelines.Data sourcesOvid MEDLINE(R), EMBASE, and Cochrane Central Register of Controlled Trials (Wiley) and reference lists of relevant articles up to 21 January 2019.Inclusion criteriaRandomised trials comparing different levels of sodium intake undertaken among adult populations with estimates of intake made using 24 hour urinary sodium excretion.Data extraction and analysisTwo of three reviewers screened the records independently for eligibility. One reviewer extracted all data and the other two reviewed the data for accuracy. Reviewers performed random effects meta-analyses, subgroup analyses, and meta-regression.Results133 studies with 12 197 participants were included. The mean reductions (reduced sodium v usual sodium) of 24 hour urinary sodium, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were 130 mmol (95% confidence interval 115 to 145, P<0.001), 4.26 mm Hg (3.62 to 4.89, P<0.001), and 2.07 mm Hg (1.67 to 2.48, P<0.001), respectively. Each 50 mmol reduction in 24 hour sodium excretion was associated with a 1.10 mm Hg (0.66 to 1.54; P<0.001) reduction in SBP and a 0.33 mm Hg (0.04 to 0.63; P=0.03) reduction in DBP. Reductions in blood pressure were observed in diverse population subsets examined, including hypertensive and non-hypertensive individuals. For the same reduction in 24 hour urinary sodium there was greater SBP reduction in older people, non-white populations, and those with higher baseline SBP levels. In trials of less than 15 days’ duration, each 50 mmol reduction in 24 hour urinary sodium excretion was associated with a 1.05 mm Hg (0.40 to 1.70; P=0.002) SBP fall, less than half the effect observed in studies of longer duration (2.13 mm Hg; 0.85 to 3.40; P=0.002). Otherwise, there was no association between trial duration and SBP reduction.ConclusionsThe magnitude of blood pressure lowering achieved with sodium reduction showed a dose-response relation and was greater for older populations, non-white populations, and those with higher blood pressure. Short term studies underestimate the effect of sodium reduction on blood pressure.Systematic review registrationPROSPERO CRD42019140812.

Species-specific responses of plant intrinsic water-use efficiency (iWUE) to multiple environmental drivers associated with climate change, including soil moisture (θ), vapor pressure deficit (D), and atmospheric CO2 concentration (c a), are poorly understood. We assessed how the iWUE and growth of several species of deciduous trees that span a gradient of isohydric to anisohydric water-use strategies respond to key environmental drivers (θ, D and c a). iWUE was calculated for individual tree species using leaf-level gas exchange and tree-ring δ13C in wood measurements, and for the whole forest using the eddy covariance method. The iWUE of the isohydric species was generally more sensitive to environmental change than the anisohydric species was, and increased significantly with rising D during the periods of water stress. At longer timescales, the influence of c a was pronounced for isohydric tulip poplar but not for others. Trees’ physiological responses to changing environmental drivers can be interpreted differently depending on the observational scale. Care should be also taken in interpreting observed or modeled trends in iWUE that do not explicitly account for the influence of D.

One effective technique for mitigating the earthquake-induced liquefaction potential is the installation of stone columns. The permeability coefficients of stone columns are high enough to cause a high seepage velocity or expedited drainage. Under such conditions, the fluid flow law in porous media is not linear. Nevertheless, this nonlinear behavior in stone columns has not been evaluated in dynamic numerical analyses. This study proposes a dynamic finite element method that integrates nonlinear fluid flow law to evaluate the response of liquefiable ground improved by stone columns during seismic events. The impact of non-Darcy flow on the excess pore pressure and stress path compared to conventional Darcy law has been investigated numerically in stone columns. Furthermore, the effects of different permeability coefficients and stone column depths have been studied under near and far field strong ground motions. The results indicate that the non-Darcy flow increases the excess pore water pressure as high as 100% in comparison to the Darcy flow.

AbstractObjectiveTo compare established associations between risk factors and mortality in UK Biobank, a study with an exceptionally low rate of response to its baseline survey, against those from representative studies that have conventional response rates.DesignProspective cohort study alongside individual participant meta-analysis of other cohort studies.SettingUnited Kingdom.ParticipantsAnalytical sample of 499 701 people (response rate 5.5%) in analyses in UK Biobank; pooled data from the Health Surveys for England (HSE) and the Scottish Health Surveys (SHS), including 18 studies and 89 895 people (mean response rate 68%). Both study populations were linked to the same nationwide mortality registries, and the baseline age range was aligned at 40-69 years.Main outcome measureDeath from cardiovascular disease, selected malignancies, and suicide. To quantify the difference between hazard ratios in the two studies, a ratio of the hazard ratios was used with HSE-SHS as the referent.ResultsRisk factor levels and mortality rates were typically more favourable in UK Biobank participants relative to the HSE-SHS consortium. For the associations between risk factors and mortality endpoints, however, close agreement was seen between studies. Based on 14 288 deaths during an average of 7.0 years of follow-up in UK Biobank and 7861 deaths over 10 years of mortality surveillance in HSE-SHS, for cardiovascular disease mortality, for instance, the age and sex adjusted hazard ratio for ever having smoked cigarettes (versus never) was 2.04 (95% confidence interval 1.87 to 2.24) in UK Biobank and 1.99 (1.78 to 2.23) in HSE-SHS, yielding a ratio of hazard ratios close to unity (1.02, 0.88 to 1.19). The overall pattern of agreement between studies was essentially unchanged when results were compared separately by sex and when baseline years and censoring dates were aligned.ConclusionDespite a very low response rate, risk factor associations in the UK Biobank seem to be generalisable.