Measuring fluence distribution of intense short laser based on the radiochromic effect.

This Letter demonstrates a novel, to the best of our knowledge, method to measure the fluence distribution of an intense short laser pulse based on the radiochromic effect. We discovered that an intense short laser pulse can induce the color reaction with a radiochromic film (RCF). Further, the net optical density of an irradiated RCF is proportional to the fluence of the incident laser pulse in a large range (${2 {-} 120}\;{{{\rm mJ}/{\rm cm}}^2}$). This method supports a large detection area up to near square-meter scale by splicing multi-pieces of RCFs (${8} \times 10\;{{\rm inch}^2}$ each). The spatial resolution reaches as high as 60 lines/mm. It offers a thin-film (${\sim}{100}\;{\unicode{x00B5}{\rm m}}$ thick), flexible, vacuum-compatible solution to intense short laser measurements, especially to laser facilities above petawatt, with beam sizes up to near square-meter scale, e.g., extreme light infrastructure.

Measurements of the Growth and Saturation of Electron Weibel Instability in Optical-Field Ionized Plasmas.

The temporal evolution of the magnetic field associated with electron thermal Weibel instability in optical-field ionized plasmas is measured using ultrashort (1.8 ps), relativistic (45 MeV) electron bunches from a linear accelerator. The self-generated magnetic fields are found to self-organize into a quasistatic structure consistent with a helicoid topology within a few picoseconds and such a structure lasts for tens of picoseconds in underdense plasmas. The measured growth rate agrees well with that predicted by the kinetic theory of plasmas taking into account collisions. Magnetic trapping is identified as the dominant saturation mechanism.

Forest gaps influence fungal community assembly in a weeping cypress forest.

The forest gap crucially influences forest environments, but its effects on local fungal community assembly are not fully understood. In this study, the fungal community in a weeping cypress forest was investigated as a function of forest gap locations based on forest clearing, using amplicon sequencing of the ITS2 region. The results showed that the fungal community significantly varied with the variations in soil properties related to gap location. Deterministic processes played pivotal roles in fungal community assembly, which was mainly driven by the temperature, moisture, available nitrogen, and microbial carbon in soil. Beta diversity of the fungal community increased from the gap center to the closed canopy. The relative abundances of dominant orders such as Microascales, Sordariales, and Chaetothyriales regularly varied as a function of gap location, and they were potential indicators for different gap locations. Based on network analysis, gap locations caused distinct co-occurrence patterns of fungal communities. This study shed light on the roles of forest gaps in the assembly of local fungal communities and provided additional strategies to manage forest ecosystems.

Physiological response and phytoremediation potential of dioecious Hippophae rhamnoides inoculated with arbuscular mycorrhizal fungi to Pb and Zn pollution.

Plant-microorganism combined remediation of heavy metal pollution has been reported, but little attention has been paid to the effect of arbuscular mycorrhizal (AM) fungi on phytoremediation of dioecious plants under heavy metal pollution. In this study, the growth, physiological responses and phytoremediation traits of Hippophae rhamnoides were determined to evaluate whether sex-specific ecophysiological responses and phytoremediation capacities of females and males are affected by additional AM fungi (Glomus mosseae) under heavy metal treatments. The results showed that excess Pb and Zn stresses inhibited photosynthetic capacities of both sexes. However, inoculated AM fungi treatment increased the activity of photosynthesis, content of photosynthetic pigment, activity of superoxide dismutase, the content of proline and root Pb content and enrichment coefficient of males while decreased root Pb content of females under Pb stress. On the other hand, inoculated AM fungi treatment increased the photosynthetic activities and Pro accumulation of females, and activity of superoxide dismutase and transport coefficient of males under Zn stress. These results demonstrate that H. rhamnoides inoculated AM fungi showed significant sex-specific responses on the growth, physiological traits and phytoremediation potential to Pb and Zn stress. AM fungi significantly improved the tolerance of males to Pb stress and both sexes to Zn stress, which indicates H. rhamnoides and AM fungi can be used as a plant-microbial combined remediation method for Pb and Zn contaminated soil. More attention should be paid on sexual-specific responses and phytoremediation of dioecious plants to heavy metals in the future.

Sex-specific competition differently regulates the response of the rhizosphere fungal community of Hippophae rhamnoides-A dioecious plant, under Mn stress.

In this study, we investigated the soil physicochemical parameters and responses of rhizospheric fungal communities of Hippophae rhamnoides to Mn stress under different sexual competition patterns. The results showed that competition significantly affects soil physicochemical properties, enzyme activity, and rhizosphere-associated fungal community structures. Under Mn stress, soils with intersexual competition had higher levels of N supply than those with the intrasexual competition. Moreover, fungal communities under intersexual interaction were more positive to Mn stress than intrasexual interaction. Under intrasexual competition, female plants had higher total phosphorus content, neutral phosphatase activity, and relative abundance of symbiotic fungi in soils to obtain phosphorus nutrients to alleviate Mn stress. In contrast, male plants had relatively stable fungal communities in soils. In the intersexual competition, rhizosphere fungal diversity and relative abundance of saprophytic fungi in male plants were significantly higher than in female plants under Mn stress. In addition, female plants showed greater plasticity in the response of rhizosphere microorganisms to their neighbors of different sexes. The microbial composition in soils of female plants varied more than male plants between intrasexual and intersexual competition. These results indicated that sex-specific competition and neighbor effects regulate the microbial community structure and function of dioecious plants under heavy metal stress, which might affect nutrient cycling and phytoremediation potential in heavy metal-contaminated soils.

O,O'-Diisopropyl S-[2-(benzene-sulfon-amido)-eth-yl]phospho-rodithio-ate.

The mol-ecular conformation of the title compound, C(14)H(24)NO(4)PS(3), the selective herbicide bensulide, is stabilized by a weak intra-molecular C-H⋯S inter-action. In the crystal, chains are formed through inter-molecular N-H⋯S hydrogen bonds.

Photon deceleration in plasma wakes generates single-cycle relativistic tunable infrared pulses.

Availability of relativistically intense, single-cycle, tunable infrared sources will open up new areas of relativistic nonlinear optics of plasmas, impulse IR spectroscopy and pump-probe experiments in the molecular fingerprint region. However, generation of such pulses is still a challenge by current methods. Recently, it has been proposed that time dependent refractive index associated with laser-produced nonlinear wakes in a suitably designed plasma density structure rapidly frequency down-converts photons. The longest wavelength photons slip backwards relative to the evolving laser pulse to form a single-cycle pulse within the nearly evacuated wake cavity. This process is called photon deceleration. Here, we demonstrate this scheme for generating high-power (~100 GW), near single-cycle, wavelength tunable (3-20 µm), infrared pulses using an 810 nm drive laser by tuning the density profile of the plasma. We also demonstrate that these pulses can be used to in-situ probe the transient and nonlinear wakes themselves.

Variable Selection with Prior Information for Generalized Linear Models via the Prior LASSO Method.

LASSO is a popular statistical tool often used in conjunction with generalized linear models that can simultaneously select variables and estimate parameters. When there are many variables of interest, as in current biological and biomedical studies, the power of LASSO can be limited. Fortunately, so much biological and biomedical data have been collected and they may contain useful information about the importance of certain variables. This paper proposes an extension of LASSO, namely, prior LASSO (pLASSO), to incorporate that prior information into penalized generalized linear models. The goal is achieved by adding in the LASSO criterion function an additional measure of the discrepancy between the prior information and the model. For linear regression, the whole solution path of the pLASSO estimator can be found with a procedure similar to the Least Angle Regression (LARS). Asymptotic theories and simulation results show that pLASSO provides significant improvement over LASSO when the prior information is relatively accurate. When the prior information is less reliable, pLASSO shows great robustness to the misspecification. We illustrate the application of pLASSO using a real data set from a genome-wide association study.

Self-reported menopausal symptoms, coronary artery calcification, and carotid intima-media thickness in recently menopausal women screened for the Kronos early estrogen prevention study (KEEPS).

OBJECTIVE: To determine whether self-reported menopausal symptoms are associated with measures of subclinical atherosclerosis. DESIGN: Cross-sectional analysis. SETTING: Multicenter, randomized controlled trial. PATIENT(S): Recently menopausal women (n = 868) screened for the Kronos Early Estrogen Prevention Study (KEEPS). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Baseline menopausal symptoms (hot flashes, dyspareunia, vaginal dryness, night sweats, palpitations, mood swings, depression, insomnia, irritability), serum E2 levels, and measures of atherosclerosis were assessed. Atherosclerosis was quantified using coronary artery calcium (CAC) Agatston scores (n = 771) and carotid intima-media thickness (CIMT). Logistic regression model of menopausal symptoms and E2 was used to predict CAC. Linear regression model of menopausal symptoms and E2 was used to predict CIMT. Correlation between length of time in menopause with menopausal symptoms, E2, CAC, and CIMT were assessed. RESULT(S): In early menopausal women screened for KEEPS, neither E2 nor climacteric symptoms predicted the extent of subclinical atherosclerosis. Palpitations and depression approached significance as predictors of CAC. Other symptoms of insomnia, irritability, dyspareunia, hot flashes, mood swings, night sweats, and vaginal dryness were not associated with CAC. Women with significantly elevated CAC scores were excluded from further participation in KEEPS; in women meeting inclusion criteria, neither baseline menopausal symptoms nor E2 predicted CIMT. Years since menopause onset correlated with CIMT, dyspareunia, vaginal dryness, and E2. CONCLUSION(S): Self-reported symptoms in recently menopausal women are not strong predictors of subclinical atherosclerosis. Continued follow-up of this population will be performed to determine whether baseline or persistent symptoms in the early menopause are associated with progression of cardiovascular disease. CLINICAL TRIAL REGISTRATION NUMBER: NCT00154180.

A LASSO-based approach to analyzing rare variants in genetic association studies.

Genetic markers with rare variants are spread out in the genome, making it necessary and difficult to consider them in genetic association studies. Consequently, wisely combining rare variants into "composite" markers may facilitate meaningful analyses. In this paper, we propose a novel approach of analyzing rare variant data by incorporating the least absolute shrinkage and selection operator technique. We applied this method to the Genetic Analysis Workshop 17 data, and our results suggest that this new approach is promising. In addition, we took advantage of having 200 phenotype replications and assessed the performance of our approach by means of repeated classification tree analyses. Our method and analyses were performed without knowledge of the underlying simulating model. Our method identified 38 markers (in 65 genes) that are significantly associated with the phenotype Affected and correctly identified two causal genes, SIRT1 and PDGFD.

Novel tree-based method to generate markers from rare variant data.

Existing methods for analyzing rare variant data focus on collapsing a group of rare variants into a single common variant; collapsing is based on an intuitive function of the rare variant genotype information, such as an indicator function or a weighted sum. It is more natural, however, to take into account the single-nucleotide polymorphism (SNP) interactions informed directly by the data. We propose a novel tree-based method that automatically detects SNP interactions and generates candidate markers from the original pool of rare variants. In addition, we utilize the advantage of having 200 phenotype replications in the Genetic Analysis Workshop 17 data to assess the candidate markers by means of repeated logistic regressions. This new approach shows potential in the rare variant analysis. We correctly identify the association between gene FLT1 and phenotype Affect, although there exist other false positives in our results. Our analyses are performed without knowledge of the underlying simulating model.