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Oil shale, as an unconventional energy source, has attracted much attention in countries worldwide. The traditional way of extracting oil shale from the open pit is not only costly but also polluting to the environment. Sufficient understanding of the relationship between subsurface fractures and temperature fields is important for the extraction of oil shale and is of great significance for the actual in-situ extraction of oil shale. The study of fracture initiation and expansion in oil shale formations is based on the effect of fractures on convective heating efficiency in oil shale in situ conversion technology. In view of the objective situation that hydraulic fracturing can enhance the rate of the permeability and heating efficiency of oil shale formations, and hence the oil yield, the effect of single fractures with different fracture heights (2 mm, 4 mm, 8 mm) on the temperature field of oil shale; and the effect of multiple fractures (two, three and four fractures) on the temperature field of oil shale are investigated under convective heating methods. [ABSTRACT FROM AUTHOR]

Plant fiber reinforced polymer matrix composites have attracted much attention in many industries due to their abundant resources, low cost, biodegradability, and lightweight properties. Compared with synthetic fibers, various plant fibers are easy to obtain and have different characteristics, making them a substitute for synthetic fiber composite materials. However, the aging phenomenon of composite materials has been a key issue that hinders development. In natural environments, moisture absorption performance leads to serious degradation of the mechanical properties of composite materials, which delays the use of composite materials in humid environments. Therefore, the effects of moisture absorption performance of plant fiber composite materials on their mechanical properties have been summarized in this article, as well as various treatment methods to reduce the water absorption of composite materials. [ABSTRACT FROM AUTHOR]

Soundless chemical demolition agents (SCDA), also known as expansive cement, represent a potentially viable method for fracturing rock without explosives. Traditionally, expansive cement is used for surface applications, such as block splitting in dimension stone quarries and demolition of concrete foundations. For deep underground applications, the major challenge with the use of expansive cement in an excavation face has been the presence of high biaxial stress field that would hinder the development of fractures in a mining face. This study aims to explore how expansive cement can be potentially used for rock fragmentation in deep underground environments. To do so, large-scale tests on 1 m × 1 m × 0.25 m concrete and granite panels with a novel drilling pattern are prepared, instrumented, and tested under biaxial confinement conditions. Test results show that the proposed drill pattern for expansive cement boreholes is capable of fracturing both panels under biaxial stresses. A 3D finite-difference modelling code FLAC3D 7.0 was developed and validated with observed panel breakage process and failure mechanisms. Both large-scale tests and numerical modelling show that expansive cement induces significant fracturing parallel to the loading plane. These findings should lay the groundwork and provide guidelines for the future application of expansive cement to underground hard rock excavations. [ABSTRACT FROM AUTHOR]

The temperature is a critical factor that determines the unfrozen water content and ice content in the frozen soil. In view of mechanical properties of the frozen soil depend on the volume of components of the four-phase systems, thus the temperature has a significant impact on the mechanical behaviors and deformation properties. The thermal state of the embankment in permafrost regions has a significant seasonal difference, then the seismic performance of the embankment alters with the season. In addition, the seismic performance is highly influenced by the properties of the earthquake motion, especially the seismic intensity. Combining these factors, a numerical simulation was conducted in this study. In this study, taking a typical section of Qinghai-Tibet Railway as an example, a numerical case study on the seismic behavior of embankment was carried out using the dynamic explicit FEM code ABAQUS/Explicit. The El Centro excitation with different intensities was performed in numerical analysis and two distinct thermal states of the embankment in extreme cold and warm days were considered as well. The seismic behaviors of the embankment, including the acceleration responses, the strain response, and the displacement response, were studied effectively. This paper proposes approaches and methods to study the seismic failure mechanism of the infrastructures, and the results can serve as a scientific basis for resisting earthquakes and preventing disasters in cold regions. [ABSTRACT FROM AUTHOR]

While drilling and blasting with explosives is widely used for rock fragmentation in mining and civil engineering, its use is associated with rigorous safety and environmental constraints as blasting creates toxic fumes, vibrations and dust. In recent years, there has been a growing interest in transitioning from blasting with explosives to rock fragmentation without explosives. In this study, the potential of expansive cement (EC), aka soundless chemical demolition agent (SCDA), as an alternative to explosives to break hard rock under confinement is explored through a comprehensive experimental and numerical modelling study. To do so, two large-scale tests have been designed and carried out on 1 m × 1 m × 0.25 m panels made from high-strength concrete and subjected to planar, biaxial loading conditions. Such test configuration is designed to mimic a mining front subjected to biaxial stresses. Different EC drill hole patterns were tested and compared. The fragmentation behaviour due to EC was first examined with five particle flow code (PFC2D) models simulating different EC drill hole patterns. Two panel designs were retained for the large-scale experiment. It is found that rock breakage with EC under confinement is feasible and promising, especially when the optimized drill pattern from numerical modelling is adopted. It is demonstrated that discrete element modeling with PFC2D can be used effectively to design and optimize the EC drill hole pattern under biaxial confinement. The findings of this study could set the stage for numerous future applications of EC for rock fragmentation of subsurface hard rock excavations such as shafts, tunnels, and mine openings. Highlights: PFC2D models are developed to examine the efficiency of expansive cement to fragment a panel under biaxial loading. Both modelling and large-scale test results indicate that panel breaks more effectively when relief holes are employed in both loading directions. Concrete panel #2 is successfully fractured using expansive cement while both in-plane and bulging failure mechanisms are observed during the test. [ABSTRACT FROM AUTHOR]

Secoisolariciresinol diglucoside (SDG) is the main component of lignans with various biological activities, including anticancer activity. However, whether SDG has obvious anticancer effects on colorectal cancer (CRC) is unclear. Pyroptosis, a form of programmed cell death, has received increasing attention in cancer‐related research. In this study, we aimed to test the anticancer properties and relatecd functional mechanisms of SDG. we found that SDG not only inhibited the cell viability of HCT116 cells, but also induced HCT116 cells to swell with apparent large bubbles, which are typical signs of pyroptosis. Furthermore, SDG induced cell pyroptosis by enhancing cleavage of the N‐terminal fragment of gasdermin D (GSDMD) in CRC cells, accompanied by increased caspase‐1 cleavage. Consistent with this, SDG‐induced GSDMD‐N‐terminal fragment cleavage and pyroptosis were reduced by siRNA‐mediated silencing of caspase‐1 or treatment with the specific caspase‐1 inhibitor VX‐765 treatment, suggesting that active caspase‐1 further induces pyroptosis. A mechanistic study showed that SDG induced reactive oxygen species (ROS) accumulation and inhibits phosphatidylinositol 3‐kinase (PI3K) phosphorylation and increases pyroptosis, while increasing GSDMD and caspase‐1 cleavage and enhancing expression of BCL2‐associated X (BAX), which could be rescued by the ROS scavenger (NAC), suggesting that SDG‐induced GSDME‐dependent pyroptosis is related to the ROS/PI3K/AKT/BAX‐mitochondrial apoptotic pathway. In vivo results showed that SDG significantly inhibited tumor growth and induced pyroptosis in the HCT116‐CRC nude mouse model. In conclusion, our findings suggest that the anticancer activity of SDG in CRC is associated with the induction of GSDMD‐dependent pyroptosis by SDG through the generation of ROS/P13K/AKT/BAK‐mitochondrail apoptosis pathway, providing insights into SDG in its potential new application in cancer treatment. [ABSTRACT FROM AUTHOR]

Training set optimization is a crucial factor affecting the probability of success for plant breeding programs using genomic selection. Conventionally, the training set optimization is developed to maximize Pearson’s correlation between true breeding values and genomic estimated breeding values for a testing population, because it is an essential component of genetic gain in plant breeding. However, many practical breeding programs aim to identify the best genotypes for target traits in a breeding population. A modified Bayesian optimization approach is therefore developed in this study to construct training sets for tackling such an interesting problem. The proposed approach is based on Monte Carlo simulation and data cross-validation, which is shown to be competitive with the existing methods developed to achieve the maximal Pearson’s correlation. Four real genome datasets, including two rice, one wheat, and one soybean, are analyzed in this study. An R package is generated to facilitate the application of the proposed approach. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Falls among older adults can lead to severe physical and psychological consequences. However, whether leisure participation changes after falling is not clear. We investigated whether falls resulted in reduced leisure participation in terms of duration, number, and intensity among older adults. Secondary data from the Health and Retirement Study and the Consumption and Activities Mail Survey (n = 1163) were analyzed. The results showed falls did not predict future leisure participation. Female, white, higher education, fewer functional limitations, and good balance were significant predictors of leisure participation at follow-up. Being white also predicted a significant decline in total number of leisure activities from baseline to follow-up, whereas higher education protected older adults from a significant reduction in total intensity of leisure activity. Our findings suggest falls may not directly affect leisure participation, but its risk factors, such as demographics, functional limitations, and balance, have a direct impact on leisure participation. [ABSTRACT FROM AUTHOR]

Simple Summary: Radiation-resistant extremophiles have frequently been found in the Taklimakan Desert, which is known for its harsh conditions. However, there is no systemic study investigating the diversity and proportion of radiation-resistant strains among culturable bacteria. The results of this study revealed the distribution of culturable bacteria in the Taklimakan Desert and indicated high proportions of radiation-resistant strains in the culturable bacteria. The study helps to better understand the ecological origin of radio-resistance and to quantitatively describe the desert as a common habitat for radiation-resistant extremophiles. The Taklimakan Desert located in China is the second-largest shifting sand desert in the world and is known for its harsh conditions. Types of γ-rays or UV radiation-resistant bacterial strains have been isolated from this desert. However, there is no information regarding the proportions of the radiation-resistant strains in the total culturable microbes. We isolated 352 bacterial strains from nine sites across the Taklimakan Desert from north to south. They belong to Actinobacteria, Firmicutes, Proteobacteria, and Bacteroidetes. The phylum Actinobacteria was the most predominant in abundance and Firmicutes had the highest species richness. Bacteroidetes had the lowest abundance and was found in four sites only, while the other three phyla were found in every site but with different distribution profiles. After irradiating with 1000 J/m2 and 6000 J/m2 UV-C, the strains with survival rates higher than 10% occupied 72.3% and 36.9% of all culturable bacteria, respectively. The members from Proteobacteria had the highest proportions, with survival rates higher than 10%. After radiation with 10 kGy γ-rays, Kocuria sp. TKL1057 and Planococcus sp. TKL1152 showed higher radiation-resistant capabilities than Deinococcus radiodurans R1. Besides obtaining several radiation-resistant extremophiles, this study measured the proportions of the radiation-resistant strains in the total culturable microbes for the first time. This study may help to better understand the origin of radioresistance, especially by quantitatively comparing proportions of radiation-resistant extremophiles from different environments in the future. [ABSTRACT FROM AUTHOR]

von Neumann [(1951). Various techniques used in connection with random digits. National Bureau of Standards Applied Math Series 12: 36–38] introduced a simple algorithm for generating independent unbiased random bits by tossing a (possibly) biased coin with unknown bias. While his algorithm fails to attain the entropy bound, Peres [(1992). Iterating von Neumann's procedure for extracting random bits. The Annals of Statistics 20(1): 590–597] showed that the entropy bound can be attained asymptotically by iterating von Neumann's algorithm. Let $b(n,p)$ denote the expected number of unbiased bits generated when Peres' algorithm is applied to an input sequence consisting of the outcomes of $n$ tosses of the coin with bias $p$. With $p=1/2$ , the coin is unbiased and the input sequence consists of $n$ unbiased bits, so that $n-b(n,1/2)$ may be referred to as the cost incurred by Peres' algorithm when not knowing $p=1/2$. We show that $\lim _{n\to \infty }\log [n-b(n,1/2)]/\log n =\theta =\log [(1+\sqrt {5})/2]$ (where $\log$ is the logarithm to base $2$), which together with limited numerical results suggests that $n-b(n,1/2)$ may be a regularly varying sequence of index $\theta$. (A positive sequence $\{L(n)\}$ is said to be regularly varying of index $\theta$ if $\lim _{n\to \infty }L(\lfloor \lambda n\rfloor)/L(n)=\lambda ^\theta$ for all $\lambda > 0$ , where $\lfloor x\rfloor$ denotes the largest integer not exceeding $x$.) Some open problems on the asymptotic behavior of $nh(p)-b(n,p)$ are briefly discussed where $h(p)=-p\log p- (1-p)\log (1-p)$ denotes the Shannon entropy of a random bit with bias $p$. [ABSTRACT FROM AUTHOR]

In a recent work, the authors demonstrated the merits of the diametrical core deformation technique (DCDT) for stress determination at an excavation face. An analytical model was developed and verified with laboratory tests. This paper aims to validate the DCDT in the field using a well-documented case study from a Canadian underground mine. Rock cores are extracted from the floor of a footwall drive 1000 m below surface for the purpose of estimating stress magnitude and orientation. The DCDT is applied to the extracted cores and the state of stress in the drift floor is estimated. On the other hand, a mine wide FLAC3D model was developed using the geomechanical data and in situ stress regime obtained from a previous study. The model is a pared-down version of a comprehensive FLAC3D mine wide model that simulates past mine-and-fill sequence and was calibrated with various burst criteria and recorded mining-induced seismic events. A comparison of FLAC3D and DCDT in terms of floor stress estimates and orientation shows good agreement. The DCDT could be used as a ground control tool to help detect stress-related ground control issues. [ABSTRACT FROM AUTHOR]

• The prevalence of falls among community-dwelling older adults was 17.7 % in the Philippines and 7.3 % in Viet Nam. • In the Philippines, factors significantly related to falls were education, living situation, functional status, pain locations, and strength. • In Viet Nam, chronic conditions, functional status, and pain were significantly associated with higher odds of falls. Falls are a significant public health issue globally. However, studies with nationally representative samples have yet to be done to understand falls among older adults in the Philippines and Viet Nam. Using a biopsychosocial perspective, this study investigated the prevalence of falls and their associated factors among community-dwelling older adults in these countries. Cross-sectional data were drawn from the baseline survey of the Longitudinal Study of Ageing and Health in the Philippines (2018, N = 4,606) and the Longitudinal Study of Ageing and Health in Viet Nam (2018, N = 4,378). The outcome variables were any falls in the past year. Independent variables included sociodemographic factors (age, sex, education, living in urban areas, living alone, social network size), biophysical factors (vision, chronic conditions, functional impairments, pain locations, insomnia symptoms, sleep medications, grip strength, walking speed, postural control), and psychological factors (depressive symptoms). Descriptive analysis and logistic regression analysis were used to analyze the data. The results showed that 17.7 % and 7.3 % of older Filipino and Vietnamese adults fell in the year before the study. Significant factors associated with the odds of any falls among Filipino older adults were having a higher level of education, living in urban areas, living with others, experiencing more functional impairments, reporting one or more pain locations, and having poor grip strength. In Viet Nam, having more chronic conditions, experiencing more functional impairments, and reporting two or more pain locations were found to be associated with higher odds of any falls. The population in the Philippines and Viet Nam is aging rapidly. Findings from this study are timely in identifying at-risk individuals and preparing for effective fall prevention strategies. [ABSTRACT FROM AUTHOR]

In this paper, considering the far-field seismic input, an accelerogram recorded in the bedrock at Wuquan Mountain in Lanzhou city during the 2008 Wenchuan Ms8.0 earthquake was selected, and numerical dynamic analyses were conducted. The one-dimensional equivalent linear method was implemented to estimate the ground motion effects in the loess regions. Thereafter, slope topographic effects on ground motion were studied by applying the dynamic finite-element method. The results revealed the relationship between the PGA amplification coefficients and the soil layer thickness, which confirmed that the dynamic response of the sites had obvious nonlinear characteristics. The results also showed that there was an obvious difference in the dynamic magnification factor between the short-period and long-period structures. Moreover, it was found that the amplification coefficient of the observation point at the free surface was greater than the point inside the soil at the same depth, which mainly occurred in the upper slope. Through this study, the quantitative assessment of ground motion effects in loess regions can be approximately estimated, and the amplification mechanism of the far-field ground motion mechanism can be further explained. In addition to the refraction and reflection theory of seismic waves, the resonance phenomenon may help explain the slope topographic effect through spectrum analysis. [ABSTRACT FROM AUTHOR]

Introduction: Recent evidence suggests that the effects of fear of falling on falls may differ by race/ethnicity. This study investigated whether race/ethnicity (white, black, and Hispanic) moderated the longitudinal effects of fear of falling on the incidence of falling and having a repeated fall among community-dwelling older adults. Methods: We used data from 2011 to 2018 of the National Health and Aging Trends Study (NHATS). These included a total of 19,516 person-intervals from 5,113 respondents. Any self-reported fall in the past year was the outcome variable with baseline fear of falling as the predictor and race/ethnicity as the moderator. Covariates included self-reported sociodemographic information, probable depression, chronic conditions, functional impairment, pain, insomnia symptoms, the Clock Drawing Test, the Short Physical Performance Battery, and grip strength. Results: Among respondents who had no experience of falling at baseline, baseline fear of falling increased the odds of having a new onset of fall at 1-year follow-up significantly among blacks, compared to whites (odds ratio [OR] = 1.85, 95% confidence interval [CI] = 1.44–2.38). No significant difference was found for Hispanics. Among respondents who already fell at baseline, baseline fear of falling increased the odds of having a repeated fall at 1-year follow-up significantly among Hispanics, compared to whites (OR = 1.91, 95% CI = 1.06–3.44). No significant difference was found for blacks. Conclusions: Clear evidence of racial/ethnic differences was found in the relationship between fear of falling and falls among community-dwelling older adults in the USA. Special attention should be paid to black older adults with a fear of falling but have not fallen down recently and Hispanics with fear of falling and have fallen in the past year. Readily available educational programs should be actively advertised to older adults to reduce the fear of falling, and at the same time, culturally tailored educational programs should be developed for older adults from racial/ethnic minority backgrounds. [ABSTRACT FROM AUTHOR]

Due to the unique conditions of the Wudong subvertical coal seam, damage to the underground roadway occurs frequently during the coal mining process. With the increase in mining depth, the energy and incidence of microseismic events increase significantly, showing characteristics of zoning and grading along the strike. Therefore, the damage to the underground roadway of the Wudong coal seam was studied with a focus on dynamic load disturbance. The results showed that the underground roadway damage exhibits asymmetric characteristics, with significant sinking on the north shoulder and various degrees of bulging on both sides of the roadway. The existing support scheme in the mine could not effectively control the deformation and damage to the rock surrounding the underground roadway under the action of dynamic loads. Therefore, the asymmetric support scheme with the high prestressed anchoring long and short anchor cable network was proposed to provide targeted reinforcement for the underground roadway, which has been shown to effectively mitigate the deformation of the surrounding rock. Eventually, considering the characteristics of microseismic event distribution and the observed increase in the rock damage with the increase of the seismic source energy, a segmented and asymmetric support scheme was suggested to tactically support the underground roadway. The findings of this study could potentially improve the ground safety of underground roadways under similar mining conditions. [ABSTRACT FROM AUTHOR]

Objective: The relationships between different insomnia symptom subtypes and the onset of depression among older adults are inconsistent. It may be that each subtype has a distinct temporal effect on depression not easily captured by the different follow-up intervals used in past studies. We systemically investigated the temporal effects by examining the links between subtypes and the onset of depression at different follow-up intervals among community-dwelling older adults.Methods: We used the 2006 wave of the Health and Retirement Study as baseline (n = 9151). The outcome was the onset of depression at 2-year (2008 wave), 4-year (2010 wave), and 6-year (2012 wave) follow-ups. The independent variables were difficulty with falling asleep (initial insomnia), waking up during the night (middle insomnia), waking up too early and being unable to fall asleep again (late insomnia), and nonrestorative sleep at baseline. Factors known to be related to depression among older adults were included as covariates.Results: Our findings showed that each insomnia symptom subtype had distinct temporal effects on the onset of depression. It appeared that the effects of initial insomnia may take longer to emerge than indicated in previous studies. Middle insomnia and late insomnia had weak relationships with depression. Nonrestorative sleep predicted the onset of depression at every follow-up period.Conclusions: We found that documenting the temporal effects of insomnia symptom subtypes helps both to classify individuals' insomnia symptoms and predict the onset of depression. We recommend taking temporal effects of insomnia symptom subtypes into account in future investigations and clinical practice. [ABSTRACT FROM AUTHOR]

A parental selection approach based on genomic prediction has been developed to help plant breeders identify a set of superior parental lines from a candidate population before conducting field trials. A classical parental selection approach based on genomic prediction usually involves truncation selection, i.e., selecting the top fraction of accessions on the basis of their genomic estimated breeding values (GEBVs). However, truncation selection inevitably results in the loss of genomic diversity during the breeding process. To preserve genomic diversity, the selection of closely related accessions should be avoided during parental selection. We thus propose a new index to quantify the genomic diversity for a set of candidate accessions, and analyze two real rice (Oryza sativa L.) genome datasets to compare several selection strategies. Our results showed that the pure truncation selection strategy produced the best starting breeding value but the least genomic diversity in the base population, leading to less genetic gain. On the other hand, strategies that considered only genomic diversity resulted in greater genomic diversity but less favorable starting breeding values, leading to more genetic gain but unsatisfactorily performing recombination inbred lines (RILs) in progeny populations. Among all strategies investigated in this study, compromised strategies, which considered both GEBVs and genomic diversity, produced the best or second-best performing RILs mainly because these strategies balance the starting breeding value with the maintenance of genomic diversity. [ABSTRACT FROM AUTHOR]

Rockbursts are some of the most dangerous phenomena encountered in underground mines. They can be triggered by an abrupt ground disturbance from a remote seismic source. In this paper, the mechanism of remotely triggered rockbursts around a coal mine drift is analyzed using the synchro-squeezing transform (SST) method and dynamic modeling. Based on seismic monitoring data, the seismic waveform at the source is estimated through empirical scaling law and calibrated in the model. Then, with the SST seismic waveform decomposition codes, the P and S waves are separated and filtered, and then applied in orthogonal oscillating directions at the source simulating their inherently diverse radiation mechanism. A three-dimensional numerical model was constructed with FLAC3D for a case study rockburst of a mine drift at Wudong Coal Mine. The static simulation results show that stress concentration occurs in the roof and rock pillar near the production level, and that the rock mass around the drift is already damaged due to the upper unloading effect and the bending deformation of the roof and pillar. Dynamic modeling confirmed that weak materials cause greater attenuation of particle vibration than hard materials. The rock mass around the drift experienced a significant strain energy release of 2.1 × 108 J and maximum displacements in the working face of 129 mm. The P wave showed a larger contribution to the dynamic disturbance in the horizontal direction than in vertical direction, while the S wave has a predominant proportion in the vertical direction. As expected, particle vibration velocity and displacement on the north side of the drift are greater than those on the south side—under incidents waves propagating from the north side. Based on model results and peak particle velocity (PPV), it was deemed that the computed released energy is large enough to threaten the drift integrity, resulting in drift damage for up to 200 m from the working face. The predicted failure characteristics and potential damage range are consistent with field observations. The proposed approach of synchro-squeezing transform (SST) and dynamic modeling could prove useful in the assessment of damage in rockburst-prone areas—it could further help assess the need for and design of dynamic rock supports. [ABSTRACT FROM AUTHOR]

The Loess Plateau is one of the most tectonically and seismically active areas in the world. Observations from past strong earthquakes, particularly the Minxian–Zhangxian and Wenchuan earthquakes, have shown distinctive evidence of seismic site effects in the mountainous area of southeastern Gansu province. In this study, seismic damage in the loess areas of southeastern Gansu province induced by these earthquakes was investigated and briefly described. Different types of ground motion were selected, and the one-dimensional equivalent linear method was used for numerical analysis of the ground motion effects in the loess regions. Moreover, seismic response analysis of a typical loess tableland was conducted. The results showed that the seismic responses of a typical loess tableland under different seismic excitations have totally different dynamic characteristics. Moreover, the seismic damage in loess regions was more serious under far-field seismic excitation compared with near-field seismic excitation with the same peak acceleration. Through this study, the quantitative assessment of ground motion effects can be approximately estimated and the mechanism of site amplification effects on ground motion is further explained. [ABSTRACT FROM AUTHOR]

In clinical trials, the efficacy of treatment might be dependent on the value of a covariate variable. Therefore, it might be possible to detect the region over the covariate variable where the two treatments under investigation do not have significantly different efficacy or the region of superiority of one treatment. The non-significant region can be verified to be a confidence interval for the abscissa of the intersection point of two regression lines, and each of the complementary regions of the confidence interval corresponds to a region of superiority. In this study, we develop a method of constructing the confidence interval based on the concept of a generalized pivotal quantity, so as to perform the task of detecting the possible three regions for a clinical trial. Two real-world examples are given to illustrate the application of our proposed method, and a simulation study is conducted to evaluate its performance. [ABSTRACT FROM AUTHOR]

Air pollution is one of the most important global environmental issues. Taiwan Environmental Protection Agency (EPA) is currently using an Air Quality Index (AQI) to measure and monitor its national air quality. The main objective of this study is to assess the air quality per hour every month in Taichung City of Taiwan from 2014 to 2016 based on the nonconformance probability of the AQI index. The nonconformance probability is defined as the probability that a characteristic of interest falls outside of an acceptance region. A lower confidence bound for the nonconformance probability is applied to test whether the AQI index value exceeds a warning threshold, and then the government could issue warnings according to the decision made by such statistical inference. An unbalanced two-way random effects model is presented for fitting the AQI index values. We evaluate three different lower confidence bound construction methods, including a t-based, an adjusted t-based and a generalized pivotal quantity (GPQ) based methods, through a detailed simulation study. Finally, a hybrid method of the t-based and the adjusted t-based estimators is recommended for practical use. [ABSTRACT FROM AUTHOR]

Background: Many studies have been conducted to investigate risk factors of falls in older people, but little is known about falls among centenarians. We analyzed the cross-sectional data from the Five-Country Oldest Old Project (5-COOP) to investigate the prevalence and correlates of falls among centenarians.Methods: Data collection was carried out in 2011-2014 in Japan, France, Switzerland, Sweden, and Denmark. The sample consisted of 1,165 centenarians who were at least 100 years old in 2011. The outcome variable was falls in the past 6 months. Demographics, chronic conditions, pain, visual impairment, global cognitive function, dizziness and syncope, number of medications, functional limitation (ie, dressing, bathing, toileting, transferring, incontinence, and feeding), mobility difficulty, poor strength, and assistive device usage were included in the analysis.Results: The prevalence of falls within the last 6 months was 33.7%, ranging from 21.6% (Japan) to 40.9% (France). Being male, experiencing dizziness, syncope, incontinence, and using assistive devices indoors were associated with an increased risk of falls among centenarians. Significant cross-country differences in the relationships between some risk factors (ie, gender, difficulty with bathing, toileting, transferring, and feeding, and using assistive devices for walking indoors and outdoors) and falls were observed. Subsample analysis using data from each country also showed that factors related to falls were different.Conclusions: The prevalence of falls among centenarians is high and fall-related factors may be different than those for their younger counterparts. Given that centenarians is an emerging population, more studies investigating risk factors are needed to better understand falls among centenarians. [ABSTRACT FROM AUTHOR]

Key message: A new optimality criterion is proposed to determine a training set for genomic selection, which is derived from Pearson's correlation between GEBVs and phenotypic values of a test set. R functions are provided to generate the optimal training set. For a specified test set, we develop a highly efficient algorithm to determine an optimal subset from a large candidate set in which the individuals have been genotyped but not phenotyped yet. The chosen subset serves as a training set to be phenotyped, and then a genomic selection (GS) model is built based on its phenotype and genotype data. In this study, we consider the additive effects whole-genome regression model and adopt ridge regression estimation for marker effects in the GS model. The resulting GS model is then employed to predict genomic estimated breeding values (GEBVs) for the individuals of the test set, which have been genotyped only. We propose a new optimality criterion to determine the required training set, which is derived directly from Pearson's correlation between GEBVs and phenotypic values of the test set. Pearson's correlation is the standard measure for prediction accuracy of a GS model. Our proposed methods can be applied to data with the varying degree of population structure. All the R functions for implementing our training set determination algorithms are available from the R package TSDFGS. The algorithms are illustrated with two datasets which have strong (rice genome dataset) and mild (wheat genome dataset) population structures. Our methods are shown to be advantageous over existing ones, mainly because they fully use the genomic relationship between the test set and the training set by taking into account both the variance and bias for predicting GEBVs. [ABSTRACT FROM AUTHOR]

Objectives Maintaining offline social participation (i.e. face-to-face social interaction) is key for healthy aging, but older adults who experience pain tend to restrict their social activity outside of the home. The onset of pain may set off a downward spiral where lowered social participation increases the risk of depression and vice versa. This study thus assesses whether online social participation (i.e. the use of online social network sites) moderates the effect of pain on depression, possibly functioning as a compensatory mechanism for reduced offline social participation for those in pain. Method Logistic regression models with a lagged dependent variable were used with panel data from the National Health and Aging Trends Study. An interaction term was included to assess the moderating effect of online social participation. Results We find that online social participation buffers the detrimental effect of pain on depression. However, the effect of pain on online social participation was not statistically significant. Discussion Findings show that online social participation can alleviate the negative effects of pain on mental well-being, and suggest that online social participation can supplement attempts to maintain offline social participation in later life, especially for those whose social activity may be limited by pain. [ABSTRACT FROM AUTHOR]

The N losses via denitrification and the N2/N2O emission ratio are highly uncertain, mainly due to methodological difficulties concerning measurement of N2 emissions. Here, we report on seasonal measurements of N2O and N2 emissions from the top soil of a winter wheat–summer maize double-cropping system in the North China Plain. A novel double cylinder soil core method was used to measure N2O and N2 fluxes in situ from a 20-year field experiment with four N fertilizer treatments (0, 200, 400, and 600 kg N ha−1 year−1) and 16 sampling occasions over a 1-year period. The N2-free helium-oxygen atmosphere in the inter-layer between the two cylinders acted as a buffer against N2 diffusion from the atmosphere into the soil core. Total N2O emissions were 0.44, 1.31, 2.19, and 2.23 kg N ha−1 year−1, and total N2 emissions were 8.3, 20.0, 22.5, and 24.7 kg N ha−1 year−1 from the N0, N200, N400, and N600 treatments, respectively. The N2/N2O emission ratio ranged from 2 to 136, indicating that N2 was the dominant gas. The N2/N2O ratio was much higher in summer than in winter, and was inversely related to fertilizer N application. Fluxes of N2 were statistically related to soil temperature and concentrations of NO3−-N and DOC in soil extracts, while N2O fluxes were related to soil water content and concentrations of NO3−-N and exchangeable NH4+ in soil extracts. The N2/N2O ratio was related to soil temperature and exchangeable NH4+ and NO3−-N concentrations. Our study provides new insights on variations of the N2/N2O emission ratio in agroecosystems, and shows the importance of seasonal measurements. [ABSTRACT FROM AUTHOR]

In this paper, the high-speed photography technique was used to study the high-speed oblique water entry of truncated cone projectiles, and the effects of nose shape, projectile velocity and entry angle on the cavity and ballistic characteristics of oblique water entry were discussed. The experimental results show that the influence of nose shape on the oblique water entry cavity and ballistic characteristics is related to the nose wetted area. For the same type of projectile, with the increase of projectile velocity, the cavity size becomes larger at the same penetration displacement and the surface closure time gets longer. Moreover, with the increase of entry angle, the surface closure time decreases, the velocity attenuation gets faster, at the same penetration displacement the cavity opening length becomes shorter and the cavity asymmetry weakens. Additionally, the results indicate that the trajectory stability of the truncated cone projectile varies under different water entry velocities and attitude angles. • The methods of experimental date processing for oblique water-entry are proposed. • The effect of nose wet area on cavity and trajectory characteristics is studied. • The effects of entry velocity and angle on oblique water-entry are analyzed. • The trajectory stability of the two truncated cone projectiles is compared. [ABSTRACT FROM AUTHOR]

Abstract Trajectory stability of high-speed water-entry projectiles is investigated experimentally in the present paper. The effects of nose shape, impact velocity, and water-entry attitude angle on the trajectory stability of the slender projectiles are identified and quantified respectively. Particular attention is related to the deviation of the centroid trajectory, and the deflection of the attitude angle. To better understand the mechanism of the stability of the trajectory, the evolution of the cavity and velocity attenuation of projectile are performed subsequently during the stage of cavitating sailing. The high-speed projectile is fired with different impact velocities and attitude angles by a light gas gun system, and a dynamic-photographic method is employed to provide digital photographic data in detail. The results show that the peak pressure generated by the flat projectile is the largest, and it exhibits a perfect trajectory stability. In contrast, the ogival projectile with the largest nose shape coefficient shows significant instability of trajectory and attitude deflection. For the same type of projectile, the trajectory instability increases with the increasing impact velocity and water-entry attitude angle. The drag coefficient of the cavitating flat projectile undergoes a prominent drop as the penetration increases. Highlights • Trajectory stability of high-speed water entry slender projectiles is identified and quantified experimentally. • Effects of nose shape, impact velocity, and water-entry attitude on trajectory are studied. • Mechanism of trajectory stability of the projectile is discussed. • A dynamic-photographic method is employed to provide digital photographic data. [ABSTRACT FROM AUTHOR]

Using real-time strong-motion observation tests of a crushed-rock embankment and a plain-fill embankment in a permafrost region of the Beiluhe River section along Qinghai-Tibet Railway (QTR), we collected the real-time acceleration data when trains were passing. We used field test data and dynamic finite element analysis software (two-dimensional, nonlinear) to analyze the characteristics of dynamic transmission, displacement response, and the stress-strain relationship of both types of embankments bearing the load of a train. By comparing the dynamic response characteristics of the plain-fill embankment, we analyzed the dynamic transmission mechanism of the crushed-rock embankment of QTR. The results showed that vibration acceleration transmission was decreased through the crushed-rock layer, which could improve the stability of the embankment. Also, the vibration settlement caused by train loading was decreased obviously in the crushed-rock layer, in which the maximum settlement displacement was only 0.81 mm, while that of the plain-fill embankment reached 1.87 mm. Thus, the crushed-rock layer changed the state of stress-strain within the embankment, which helped increase the maximum principal stress of the embankment and decrease the amplitude and range of the maximum shear strain. [ABSTRACT FROM AUTHOR]

A study was conducted to investigate the potential use of Clostridium autoethanogenum protein (CAP) replacing fish meal (FM) in the diet of red swamp crayfish (Procambarus clarkia). Crayfish were fed with FM-based diet and diets with graded levels of CAP replacing FM at 25%, 50%, 75%, and 100%, respectively. Compared to the FM group, the growth performance and feed utilization of crayfish were not significantly influenced by CAP inclusion. The best weight gain of crayfish was observed in the 25% CAP replacement group. The content of arginine, histidine, tyrosine, cysteine, and hydroxyproline of muscle increased at first and then decreased, showing a quadratic relationship with CAP level. The activity of serum aspartate aminotransferase (AST) linearly increased, while alanine aminotransferase (ALT) firstly decreased and then increased with the increase of CAP level. The activity of serum phenoloxidase, gene expression of cyclophilin A (cypa), hemocyanin A chain-like (hem B), and hemocyanin B chain-like (hem B) in hepatopancreas of crayfish were increased in the 25 and 50% CAP replacement group, but were decreased at 100% replacement level. Enteritis was not observed among all the diet groups. The average length of longitudinal ridges was linearly decreased with the increment of CAP level, although it was highest in the 25% CAP replacement group. The overall structure of intestinal microbial community was similar among different experiment conditions, but Shannon and Simpson diversity indexes were quadratically influenced by CAP inclusion. Tyzzerella , Sphingomonas , and Weissella were enriched in the intestine of crayfish fed CAP diets. In conclusion, CAP replacing FM at tested levels did not impact growth performance of crayfish. CAP replacing FM at 25% and 50% improved immune response and muscle amino acid composition but depressed immunity at 100% replacement level. CAP tend to compromise intestinal histology and hepatopancreas health, change the α-diversity and genus composition of intestinal microbiota. It is recommended that CAP replacing 25% FM in a diet containing 10% fish meal could achieve the optimal growth performance, immune response, amino acid composition, and intestinal histology for 6 g crayfish. • Clostridium autoethanogenum protein (CAP) replacing fish meal (FM) did not affect growth performance and feed utilization of crayfish (Procambarus clarkii). • CAP replacing FM at 25% and 50% increased the immune response and amino acid profile, but depressed immunity of crayfish at 100%. • CAP replacing FM at the test levels tended to depress intestinal morphology and hepatopancreatic health of crayfish. • The overall intestinal microbial community structure of crayfish was not altered by CAP inclusion. • CAP changed α-diversity and abundance of intestinal bacteria genera of crayfish. [ABSTRACT FROM AUTHOR]

Prestressed anchored cables have been widely used in slope reinforcement engineering, but prestress variations in these cables are not fully understood, particularly for anchored cables bolted into strata that have undergone time-dependent excavation unloading destruction (EUD). In this paper, we investigate the factors that influence variations in anchored cable prestess in EUD strata, and proposed a variation prediction model based on the equal-strain assumption for the anchored cable and the rock mass. The new model is validated with field data from a real case study, demonstrating the model's improved prediction capability and potential for wider applications. One direct application of the new method is to predict the long-term variations in anchored cable prestress and evaluate the anchoring conditions, which can provide theoretical guidance for the safe operation and management of prestressed anchor engineering projects. [ABSTRACT FROM AUTHOR]

Due to the vulnerability of permafrost environment to climate changes, permafrost in the Qinghai-Tibet Plateau (QTP) is experiencing thickening of the active layer and warming ground temperatures that together have a significant influence on the ground motion characteristics. A series of in situ wave velocity tests were carried out in permafrost regions along the Qinghai-Tibet Railway (QTR) and the characteristics of shear wave velocity of frozen soil were summarized. Then, the ground motion responses in permafrost regions were simulated, and the impact of permafrost change on the seismic site response was discussed. Moreover, the dynamic response of the traditional embankment at the Beiluhe site in permafrost regions was studied. The changes of ground motion parameters were significantly impacted and showed reproducible changes with different active layer thicknesses and permafrost thicknesses. The ground motion amplification coefficients increased with the increase of active layer thickness, and the amplification coefficients were greater in a warm season than that in a cold season. Furthermore, the active layer thickness had little influence on the characteristic site period, and the variation of the characteristic site period with the permafrost thickness showed the logarithmic variation characteristic. Compared with the soil profile away from the center of the railway subgrade, the acceleration under the embankment showed a significant increase due to the overlying subgrade embankment. The increase in amplitude was about 29%, which illustrated that the deformation of the soil under the embankment became greater and may be more prone to damage during the seismic loading. [ABSTRACT FROM AUTHOR]

Ongoing climate changes posed significant threats to forest growth, structure and ecological functions. However, in our field survey in the east Qilian Mountains, we found that growth condition of Qinghai spruce under climate changes was better in anthropogenic management forest than disturbance-free stands. Accordingly, we suggested a hypothesis that the environmental change induced suppression in Qinghai spruce growth could be mitigated by anthropogenic management. Such a hypothesis was tested by comparing Qinghai spruce growth and population dynamic patterns between anthropogenic-managed forests and disturbance-free ones. We found that Qinghai spruce radial growth persistently declined since the late 1950s in the disturbance-free forests, while the radial growth of anthropogenic-managed trees almost kept steady-going trends since the 1970s in which anthropogenic-management appeared. Besides, some anomalous growth-declining years occurred in disturbance-free forests did not appear in anthropogenic-managed forests in the same year after anthropogenic-management emerged. Moreover, missing ring and tree mortality took place in disturbance-free stands and became increasingly frequent after the mid-1980s. The frequencies and proportions of missing rings and tree die-off were much lower in anthropogenic-managed forests than disturbance-free ones. Additionally, the occurrence of Qinghai spruce radial growth decline and increased mortality in recent time in our disturbance-free forests could be well explained by global-change-type drought in conjunction with elevated temperature and warming-related pest outbreaks. These results would be of fundamental significance for the further understanding of the changing forests, which could provide new clues for forest management and conservation in the future. [ABSTRACT FROM AUTHOR]

Under the assumption of random block effects, a new class of two-level factorial block designs with partial replication is proposed for estimating the user-specified requirement sets and variance components. A noteworthy feature of the proposed designs is that the within-block and between-block replicates are both conducted, such that the components of variance can be unbiasedly estimated. Under the framework of parallel-flats block designs, a set of sufficient conditions is presented for design characterization, and an algorithm is developed for systematically constructing the proposed designs. Using the proposed algorithm, a design catalogue is generated as a reference for experimentation. Some examples are given to demonstrate that the proposed designs are promising alternatives for practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The present study examined whether ethnicity independently predicted future falls among community‐dwelling older Singaporeans, and whether ethnicity moderated the relationships between falls risk factors at baseline and falls at follow up. Methods: Data from a longitudinal survey of older Singaporeans were used. Baseline assessment included handgrip strength, global cognitive function, mobility difficulties, health and psychosocial status. One‐year retrospective falls information at follow up was the primary outcome. Results: Final analysis included 1975 participants (mean age 73.6 ± 6.2 years, 53% women). Indians, followed by Malays, had a higher risk of falling compared with Chinese at follow up. This association remained after controlling for falls risk factors. Self‐reported pain and poor global cognitive function imposed a substantial increment in the risk of falling among Malays compared with Chinese, but not Indians. Conclusion: Ethnicity was a significant predictor of future falls among older Singaporeans. Falls screening and intervention should take ethnicity into account to reach and support the appropriate target population. Geriatr Gerontol Int 2018; 18: 72–79. [ABSTRACT FROM AUTHOR]

Shielding against spatial high-energy electron radiation is essential to the success of space exploration. Honeycomb and foam systems, combined with a magnetic field, were proposed to shield against spatial high-energy electrons given the immense mass and large amount of secondary X-rays of a passive shield and the demand for a high-intensity magnetic field of an active method. The shielding capabilities of several structures were investigated using the Monte Carlo method. The influences of magnetic flux density and hollow cube size on shielding property were studied by simulating energy deposition in a Chinese male reference phantom. Results showed that the honeycomb and foam systems enhanced the shielding capability against high-energy electrons and reduced the penetration of secondary X-rays. The effective dose in the male phantom decreased with increasing magnetic flux density. The proposed structures exhibited excellent shielding capabilities with a small hollow cube. In addition, the foam structure performed better than the honeycomb structure. Thus, the presented systems may be used for space radiation protection in a high-energy electron environment. [ABSTRACT FROM AUTHOR]

Loess is widely distributed in the western part of China and its area comprises 6.6% of Chinese territory. Because of the characteristics of high porosity, low strength, and weak cementation, the loess is characterized by high seismic vulnerability which has been observed and confirmed by many researchers at home and abroad. The postquake field investigation and the laboratory study have shown that the ground motion effects, including the amplification effects and slope effects, were obvious in loess sites. Moreover, the causes of landslides, seismic subsidence, and liquefaction were mainly attributed to this special soil structure and properties. In this paper, based on the data of shear wave velocity of typical loess in Lanzhou region, combining the results of dynamic triaxial tests, the numerical analysis of ground motion effects in the loess regions is analyzed. The results reveal how the ground motion effects are checked and demonstrated the important role of numerical simulations while studying the characteristics of ground motions. [ABSTRACT FROM AUTHOR]

• A novel hybrid deep model is proposed for multi-step-ahead wind energy forecasting. • An encoder-decoder framework is designed to extract comprehensive features. • A teacher-forcing strategy is introduced to train the model and make forecasts. • The superiority of the proposed model is verified on datasets from diverse areas. Accurate multi-step-ahead wind speed (WS) and wind power (WP) forecasting are critical to the scheduling, planning, and maintenance of wind farms. Previous forecasting methods tend to focus on improving forecast accuracy by integrating different models and disaggregating data while neglecting the forecasting ability of basic models. In addition, traditional multi-step-ahead output strategies have limitations that constrain the forecasting capability of models. To overcome the above challenges, this study proposes a novel forecasting model called ED-Wavenet-TF. It adopts two Wavenet networks as Encoder and Decoder connected by the multi-head self-attention mechanism. And, teacher forcing is used as the multi-step-ahead output strategy for WS and WP forecasting. In the training phase, ED-Wavenet-TF uses a portion of the actual data to correct the errors at the intermediate forecasting steps, while in the forecasting phase, it runs through an inference loop to make forecasts. In this study, two WS datasets and two WP datasets are used to validate the performance of ED-Wavenet-TF with univariate input. The results show that compared with Wavenet, the symmetric mean absolute percentage error of ED-Wavenet-TF at four forecasting steps is lower by at least 4.8577% on average for the WS datasets and 8.9463% on average for the WP datasets. The advantages of ED-Wavenert-TF over ten comparable models are confirmed by four evaluation indicators and the Harvey, Leybourne, and Newbold statistical hypothesis test. Moreover, ED-Wavenet-TF is extended to make multi-step-ahead forecasts with multivariate inputs, whose effectiveness is demonstrated on another open WS dataset. [ABSTRACT FROM AUTHOR]

ABSTRACT Owing to a lack of available long-term climatic records, data related to past climatic variability throughout the Tibetan Plateau remains limited. In this study, we found that Qilian juniper tree growth was significantly and positively correlated ( p < 0.001) to yearly mean temperatures in the northeastern margin of the Tibetan Plateau. We developed an annual mean temperature reconstruction from year 1740 CE based on growth-climate relationships in the study area. Our reconstruction accounted for 53.9% of total variance from 1956 to 2012 (the calibration period). Through this reconstruction, we were successfully able to capture recent abrupt climate change events that generally agreed with other temperature-sensitive tree-ring reconstructions on both regional and hemisphere scales under a decadal timescale. Periods from 1820 to 1830, 1855 to 1890, and 1960 to 1985 CE corresponded to cold periods in the reconstruction, while the 1740s and periods from 1795 to 1815 and from 1990 to 2012 CE corresponded to relatively warm periods. We also detected increased interannual change variability in annual mean temperatures since the 1980s, which could be related to increasing variability in the East Asian winter monsoon as well as the rapid climate warming that has occurred since this time. From these reconstructed temperatures, we were successfully able to capture the occurrences of large volcanic events in China as well as five historic volcanic events outside China that had global implications on climate variability and that resulted in planetary cooling during the period from 1740 to 2012 CE. This in turn suggested that these volcanic events would have had short-lived impacts (approximately from 1 to 3 years) on temperature variation in the study area. The aim of this study was to provide a perspective in which to explore the mechanisms that simultaneously influence tree rings and climate. [ABSTRACT FROM AUTHOR]

Alpine forest population dynamics are sensitive to climate change. Response patterns are complex, and it is still unclear as to whether or not population dynamics are species-dependent. In this study, population dynamic patterns for alpine timberline Qilian juniper and Qinghai spruce tree species in the mid Qilian Mountains were determined from approximately 1500 C.E. by applying dendrochronological methods. The results showed that these tree species have different forest population dynamics. The Qinghai spruce recruitment rate was clearly higher than that of Qilian juniper. Furthermore, the temporal population dynamic patterns of Qinghai spruce samples taken at different sites were consistent whereas those of the Qilian juniper samples were not. Qinghai spruce population dynamics were primarily affected by temperature, with positive correlations between temperature and recruitment. By contrast, with the exception of a positive to negative shift in the relationship between temperature and Qilian juniper population dynamics, Qilian juniper recruitment significantly decreased when its density reached a relatively high level. Moreover, a shift in the temperature-recruitment relationship and a decrease in recruitment occurred simultaneously, indicating that Qilian juniper population dynamics were affected by both temperature and density. Species to species differences were also observed when compared with previous studies within the mid Qilian Mountains, confirming the existence of species-dependent population dynamic patterns. Forest recruitment dynamic patterns and tree recruitment-climate relationships may help to provide clues for future studies on forest management, conservation and utilization. [ABSTRACT FROM AUTHOR]

Objective. We aimed to systematically assess the efficacy of Chinese herbal medicine (CHM) as an adjunctive therapy on in-hospital mortality in patients with acute kidney injury (AKI). Methods. We did a systematic review of articles published in any language up until Jun 23, 2015, by searching PubMed, Embase, the Cochrane Library, CBM, and CNKI. We included all RCTs that compared outcomes of patients with AKI taking CHM plus Western treatment (WT) with those taking WT alone. We applied Cochrane risk-of-bias tool to assess the methodological quality of the included trials. Results. Of 832 citations, 15 studies involving 966 patients met inclusion criteria. The methodological quality was assessed with unclear risk of bias. In the primary outcome of meta-analysis, pooled outcome of in-hospital mortality showed that patients randomly assigned to CHM treatment group were associated with low risk of in-hospital mortality compared with those randomly assigned to WT alone (RR = 0.41; 95% CI = 0.24 to 0.71; P=0.001). Conclusions. CHM as an adjunctive therapy is associated with a decreased risk of in-hospital mortality compared with WT in patients with AKI. Further studies with high quality and large sample size are needed to verify our conclusions. [ABSTRACT FROM AUTHOR]

Dynamic disturbance from far-field seismic events is one of the main causes for triggering rockbursts in underground excavations. In this study, a comprehensive methodology for the simulation of a remote seismic source is proposed. The methodology encompasses the processing of raw seismic waveform based on the synchro-squeezing transform (SST) method and numerical modelling using finite-difference code FLAC3D. The main contributions of this study are as follows. First, the raw waveform is processed and reconstructed into P- and S- waveforms using the SST method, which is superior to applying synthetic waveforms in seismic modelling. Secondly, an innovative source waveform and material damping calibration procedure is put forward based on the empirical scaling law, producing a generalized seismic source waveform with input level of energy. Furthermore, a seismic loading scheme in numerical modelling is proposed; a spherical point source is created for applying P- and S- waveforms in different theoretical directions. Numerical modelling results show that the theoretical directionalities of P- and S- waves are well differentiated and reflected using the proposed dynamic loading method. The peak particle velocity (PPV) and peak kinetic energy density distributions around openings are interpreted, demonstrating that the proposed methodology could assist in rockburst risk assessment and dynamic rock support design • Rockburst trigger by a remote seismic source is simulated in numerical modelling. • Raw seismic waveform is processed using synchrosqueezing transform (SST) method. • Innovative source waveform and damping calibration procedure is presented. • The proposed methodology can assist in rockburst prediction and support design. [ABSTRACT FROM AUTHOR]

Hydrodynamic ram (HRAM) is a phenomenon that occurs when a high-speed projectile penetrates a fluid-filled tank, where the energy transferred to the liquid could result in a catastrophic failure and excessive structural damage. It is essential to take physical comprehension of the hydrodynamic effects that occur during an HRAM event in the civilian domain as well as for the military aircraft design, which would in fact contribute to design better structures with respect to this particular threat. For this present work, the HRAM due to cavity evolution in confined vessels under ballistic impact by projectiles was investigated through theoretical analysis combined with experimental results. Taking the confinement effects due to the limited size of the fluid-filled vessel and corresponding structure deformation into account, a model is proposed to describe the pressure between the liquid and vessel wall along the penetration trajectory based on cavity dynamics analysis. By studying relevant parameters, changes of wall pressure, non-dimensional disturbance range and energy of two extreme containers, (namely, non-pressure resistance containers and rigid containers without deformation) were examined. The results show that the cavitation pressure has less intense peak but much greater temporal extent compared with the pressure generated during the shock stage, thereby the cavity pressure impulse induced by cavity evolution is a non-negligible factor affecting the deformation and failure of a fluid-filled vessel. The aim of the present work is to reveal the mechanism of the pressure acting on the container wall caused by cavity evolution rather than the initial shock wave in an HRAM event, which will help to study the nature of hydrodynamic ram and understand the role of the cavitation pressure in the damage or deformation of liquid-filled vessels under projectile impact. • Considering the vessel deformation, an energy conservation equation is built. • A model is proposed to describe the wall pressure induced by cavity evolution. • The cavitation pressure distribution along the penetration trajectory is studied. • Energy distribution along the penetration trajectory is studied. • Vessel size confinement effect on cavity evolution is analyzed. [ABSTRACT FROM AUTHOR]

In practice, the variance of the response variable may change as some specific factors change from one setting to another in a factorial experiment. These factors affecting the variation of the response are called dispersion factors, which can violate the usual assumption of variance homogeneity. In this study, we modify the conventional minimum aberration criterion to take the impact of dispersion factors into account. The situations of one or two dispersion factors are investigated. As a result, we present regular 2n − pdesigns with run sizes equal to 16 and 32 using the modified minimum aberration criterion. [ABSTRACT FROM AUTHOR]

A new class of robust designs against missing data, called the minimum breakdown designs, is proposed for two-level orthogonal main-effect plans. The minimum breakdown designs provide the highest probability to derive a non-singular residual design for estimating the grand mean and all the main effects, when a fraction of experimental data is unavailable. Some theoretical and computational results for characterizing the minimum breakdown designs are developed. In addition, a catalogue of the proposed designs with practical run-sizes is presented for multifactorial experiments. [ABSTRACT FROM AUTHOR]

To provide a general view of how the shock waves propagate and multi-reflect in a water-filled tank, a discrete method for the propagation of shock waves produced by high-speed projectile water entry was proposed based on the law of reflection in this present study. This method was employed to analyze the composition of shock wave fronts at typical moments, the reflection history of any point on the reflected wave front, and the reflection history of points on the arc of a continuous reflected wave front without inflection. Meanwhile, a shadowgraph visualization system for shock waves induced by high-speed projectile water entry was designed and used to capture the shock wave front propagation in the water-filled tank. So that, the images and the wave fronts obtained by the discrete method were combined to analyze the propagation characteristics of the shock wave produced by projectile water entry. Good agreements were found between the theoretical predictions and experimental results. • A discrete method for shock wave propagation in a water-filled tank was proposed. • The composition and reflection history of shock wave fronts were analyzed. • A shadowgraph visualization system for shock waves was designed. • Good agreements were found between the theoretical and experimental results. [ABSTRACT FROM AUTHOR]

Key message: A practical approach is developed to determine a cost-effective optimal training set for selective phenotyping in a genomic prediction study. An R function is provided to facilitate the application of the approach. Genomic prediction (GP) is a statistical method used to select quantitative traits in animal or plant breeding. For this purpose, a statistical prediction model is first built that uses phenotypic and genotypic data in a training set. The trained model is then used to predict genomic estimated breeding values (GEBVs) for individuals within a breeding population. Setting the sample size of the training set usually takes into account time and space constraints that are inevitable in an agricultural experiment. However, the determination of the sample size remains an unresolved issue for a GP study. By applying the logistic growth curve to identify prediction accuracy for the GEBVs and the training set size, a practical approach was developed to determine a cost-effective optimal training set for a given genome dataset with known genotypic data. Three real genome datasets were used to illustrate the proposed approach. An R function is provided to facilitate widespread application of this approach to sample size determination, which can help breeders to identify a set of genotypes with an economical sample size for selective phenotyping. [ABSTRACT FROM AUTHOR]

Conformance proportion is the proportion of a performance characteristic of interest that falls within a prespecified acceptance region, which has been used in various applications. In this article, a simple closed-form interval estimation, based on Student's t statistic, is proposed for unilateral conformance proportions in balanced and unbalanced random-effects models. Two real datasets are analyzed to illustrate the proposed method, whose performance is also evaluated through detailed simulation studies. The simulation results reveal that the empirical coverage probabilities for upper confidence limits of the method are sufficiently close to the nominal values, but those for lower confidence limits appear to be slightly less than the nominal level. Furthermore, a bootstrap-based calibration for both upper and lower confidence limits is provided to have empirical coverage probabilities closer to the nominal level. This article has supplementary material online. [ABSTRACT FROM AUTHOR]

Magnetocardiography (MCG) has been investigated as a tool for noninvasive detection of coronary artery disease (CAD). In this study, the area ratio of positive and negative magnetic induction extracted from an extrema circle in the magnetocardiogram was analyzed at specific time points in the cardiac cycle: P maximum, R peak, J point, T onset, T peak and T end. The area of the positive proportion of the magnetic field relative to the total area within a circle encompassing the field extrema was determined and proposed for fast-speed CAD diagnosis. MCG was performed with a 61-channel biomagnetometer in a shielded environment in 38 healthy subjects and 15 CAD patients. A notable difference in area ratio was found between healthy and CAD subjects at the peak time of T wave: 0.416 ± 0.090 versus 0.465 ± 0.065 ( p = 0.013). Using a cutoff value of 0.4506 resulted in a sensitivity and specificity of 86.7 % and 73.8 %, respectively. This approach may enable a fast-speed CAD diagnosis in a clinical setting. [ABSTRACT FROM AUTHOR]

Highlights: [•] We developed a swab-SERS method for thiabendazole detection on apple surfaces. [•] A partial least square model was built for quantitative measurement. [•] This swab-SERS method is simple, sensitive, rapid, and fairly quantitative. [•] This method can be extended to detect other pesticides on thick skinned surfaces. [Copyright &y& Elsevier]

Due to the lack of a replication-based estimate for the experimental error variance, unreplicated orthogonal main-effect plans (OMEPs) usually appear to be unsatisfactory in screening active factors, when there are certain interactions likely to be non-negligible. In this study, partially replicated designs constructed through two-level orthogonal arrays are recommended to compensate for this deficiency. A compound criterion called the extended minimum aberration (EMA) is proposed for choosing the twice-replicated fractions. According to the EMA criterion, sufficient conditions for constructing the minimal two-level OMEPs with partial replication are proposed, and a series of EMA designs with practical run-sizes is provided for practical applications. The Canadian Journal of Statistics 42: 168-183; 2014 © 2014 Statistical Society of Canada [ABSTRACT FROM AUTHOR]