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The added value of candidate predictors for risk modeling is routinely evaluated by comparing the performance of models with or without including candidate predictors. Such comparison is most meaningful when the estimated risk by the two models are both unbiased in the target population. Very often data for candidate predictors are sourced from nonrepresentative convenience samples. Updating the base model using the study data without acknowledging the discrepancy between the underlying distribution of the study data and that in the target population can lead to biased risk estimates and therefore an unfair evaluation of candidate predictors. To address this issue assuming access to a well-calibrated base model, we propose a semiparametric method for model fitting that enforces good calibration. The central idea is to calibrate the fitted model against the base model by enforcing suitable constraints in maximizing the likelihood function. This approach enables unbiased assessment of model improvement offered by candidate predictors without requiring a representative sample from the target population, thus overcoming a significant practical challenge. We study theoretical properties for model parameter estimates, and demonstrate improvement in model calibration via extensive simulation studies. Finally, we apply the proposed method to data extracted from Penn Medicine Biobank to inform the added value of breast density for breast cancer risk assessment in the Caucasian woman population. [ABSTRACT FROM AUTHOR]

Object detection can be formulated as a point matching problem when objects are modeled by point sets. Moments, which have been widely used for point matching, are limited to affine transformations as their support point sets cannot keep invariant. To address this problem, we developed an affine invariant centroid tree (AICT) to obtain a rigorous affine invariant support point set (SPS). The algorithm is constructed by a recursive process: the point set is first divided by the vector from the certain point to the centroid of the point set, and the centroids of subsets are used to generate vectors for renewed partitions. In addition, the centroids of the subsets are stored to form an AICT. The AICT represents the inherent structure of the point set. It is highly tolerant to noise and outliers due to the partitions on the whole point set. More importantly, it is affine invariant owing to the affine invariance of partition. Therefore, we can get rigorous affine invariant descriptors while moments are combined with AICT. The experimental results on synthesized and real data verify that our proposed algorithm outperforms the state-of-the-art point matching methods including shape context, iterative closet point, and the method adopting thin plate spline for rigid robust point matching (TPS-RPM). [ABSTRACT FROM AUTHOR]

In this work, the bio-based epoxy nanocomposites (GER/DOPO-POSS) were prepared, and AE-POSS was synthesized and used as compatibilizer for GER/DOPO-POSS nanocomposites. The effects of AE-POSS content on mechanical properties, thermal stability, compatibility and flame retardancy of GER/DOPO-POSS nanocomposites were discussed. The results showed that the addition of AE-POSS significantly improved the dispersity of DOPO-POSS in gallic epoxy matrix. AE-POSS can improve both the thermal stability and flame retardancy of GER/DOPO-POSS nanocomposites. When 6.0 wt % AE-POSS was added in GER/DOPO-POSS, the limiting oxygen index of it was 25.6%, and the initial thermal degradation temperature of it was 36 °C higher than that without AE-POSS. [ABSTRACT FROM AUTHOR]

Cortical information has great importance to reflect the deep brain stimulation (DBS) effects for Parkinson's disease patients. Using cortical activities to feedback is an available closed-loop idea for DBS. Previous studies have demonstrated the pathological beta (12–35 Hz) cortical oscillations can be suppressed by appropriate DBS settings. Thus, here we propose to close the loop of DBS based on the beta oscillations in cortex. By modify the cortico-basal ganglia-thalamic neural loop model, more biologically realistic underlying the Parkinsonian phenomenon is approached. Stimulation results show the proposed closed-loop DBS strategy using cortical beta oscillation as feedback information has more profound roles in alleviating the pathological neural abnormality than the traditional open-loop DBS. Additionally, we compare the stimulation effects with subthalamic nucleus feedback strategy. It is shown that using cortical beta information as the feedback signals can further enlarge the control parameter space based on proportional-integral control structure with a lower energy expenditure. This work may pave the way to optimizing the DBS effects in a closed-loop arrangement. [ABSTRACT FROM AUTHOR]

A cross-region transfer learning method is proposed to identify community (e.g. car parks, public spaces and shopping centers) fire hazards based on text input provided by community members. The key component of the method, which also accounts for data imbalance, is an improved transfer component analysis that is embedded with a local discriminant analysis to transfer non-local rich knowledge to the fire hazard identification of local communities with an insufficient number of samples. In addition, a fire hazard knowledge map is established and applied to supplement the missing key features for fire hazard identification, and ontology modeling is applied to standardize the text features and reduce the effect of semantic ambiguity brought by cross-region knowledge transfer. The proposed method is verified based on the text data of nine fire hazard classes from Lanzhou and Beidaihe in China. Machine learning experiments show that fire hazard identification performance of all nine classes were improved with the overall accuracy, precision, recall, F1 score and AUC increased by 12%, 15%, 16%, 15% and 15%, respectively. Under data imbalance scenarios, the proposed method outperforms the state of the art methods, such as sampling-based methods, FastText and ULMFiT. The results also show that the proposed method can achieve desired performance with only half of the training samples. These findings illustrate that the proposed method can assist regions by improving fire identification results significantly through knowledge transfer. The proposed approach can be followed to build smart systems for community fire risk management with reasonable performance and high efficiency. [ABSTRACT FROM AUTHOR]

In community emergency management, it is crucial to generate evacuation task plans (ETPs) to help reduce risks in complex disaster situations. Case-driven and model-driven approaches have their respective advantages in generating ETPs, which can complement each other. With case-driven approach, historical experience can be fully used to establish the relationship between typhoon scenarios and historical ETPs. Through model-driven approach, the continuity of ETPs can be guaranteed when required information to operate the plans is missing. This study aims at proposing an integrated approach that can combine the benefits of both case-driven approaches and model-driven approaches. Based on the structural modeling of evacuation tasks, this paper proposes an integrated approach to generate ETPs for community typhoon emergencies. Finally, a case that is based on actual problems is provided to verify the reasonability and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

An infrared image-based feedback control system for intelligent fire monitor was proposed in this paper, whose aims are to realize automatic aiming of the fire site and continuous fire tracking in the process of fire extinguishing through adjusting of the yaw angle of the fire monitor. Firstly, infrared camera was used to capture images of the fire site, and under high temperatures, the fire would be easily observed. An improved adaptive image threshold segmentation scheme was developed for image background segmentation and fire acquisition. The fire region in the captured image was considered as region of interest (ROI) and the geometric center of which was calculated. Due to the special advantageous structural design of the proposed system, the geometric center of ROI representing the actual fire was considered as the direction which the fire monitor should aim at. Furthermore, a fuzzy control scheme simulating the operating mode of firefighters was proposed, and the ROI center position deviation and deviation rate were considered as inputs of the control system. Experimental results show that, after the fire was detected by the system, the fire monitor could be yawed to the direction of the fire within 2000 ms, and the deviation of image position is less than 1.6 pixels. Similarly, the proposed system could be well adapted to the changing position of the fire caused by combustion. And after no more than image iteration of three frames, the controller realizes aiming of the fire by the fire monitor, and the final deviation is less than 0.1 pixels. In general, the proposed infrared image feedback control system for fire horizontal position aiming of intelligent fire monitor has great potential for intelligent fire extinguishing by fire-fighting robots. [ABSTRACT FROM AUTHOR]

Chemical design of SiO2-based glasses with high elastic moduli and low weight is of great interest. However, it is difficult to find a universal expression to predict the elastic moduli according to the glass composition before synthesis since the elastic moduli are a complex function of interatomic bonds and their ordering at different length scales. Here we show that the densities and elastic moduli of SiO2-based glasses can be efficiently predicted by machine learning (ML) techniques across a complex compositional space with multiple (>10) types of additive oxides besides SiO2. Our machine learning approach relies on a training set generated by high-throughput molecular dynamic (MD) simulations, a set of elaborately constructed descriptors that bridges the empirical statistical modeling with the fundamental physics of interatomic bonding, and a statistical learning/predicting model developed by implementing least absolute shrinkage and selection operator with a gradient boost machine (GBM-LASSO). The predictions of the ML model are comprehensively compared and validated with a large amount of both simulation and experimental data. By just training with a dataset only composed of binary and ternary glass samples, our model shows very promising capabilities to predict the density and elastic moduli for k-nary SiO2-based glasses beyond the training set. As an example of its potential applications, our GBM-LASSO model was used to perform a rapid and low-cost screening of many (~105) compositions of a multicomponent glass system to construct a compositional-property database that allows for a fruitful overview on the glass density and elastic properties. [ABSTRACT FROM AUTHOR]

Water is required to reach the ignition location accurately to ensure rapid fire extinguishing in the process of automatic fire suppression. In this paper, a water jet trajectory model was established based on the Moving Particle Semi-implicit (MPS) method, the experimental trajectory data were also collected through the experimental platform system and compared with the simulation trajectory data. Under low initial velocity, the results of simulation matched well with the experimental data while there were large errors under high velocity. It was found that air resistance was the main reason for deviation, the longer flight time caused by the high initial velocity and the bigger stressed area after the water jet break-up were main causes for the greater impact from air resistance. The binary function interpolation compensation method was used for error compensation and the jet angle and initial velocity were selected as error factors. The trajectory model was corrected based on existing simulation and experimental data and verified through unused data. The results showed that the revised trajectory model can accurately predict the position of the jet trajectory and provide data support for automatic fire suppression systems. [ABSTRACT FROM AUTHOR]

MAS1 is a lipase isolated from Streptomyces sp. strain W007 with potential application in biotechnology. Structural analysis of MAS1 lipase showed that eight amino acids with bulkier side located in the substrate-binding pocket may be involved in affecting catalytic performance. Alanine substitutions of those residues were conducted to reduce steric clash of catalyzed pocket and probe their functional roles. The kcat/Km of mutants H108A, F153A, and V233A increased to 2.3-, 2.1-, and 1.4-fold, respectively. Interestingly, the half-life (60 °C) of F153A had shifted to 523 min after mutagenesis, which was fivefold enhancement toward that of MAS1 wide-type. Furthermore, higher hydrolysis ability of mutants H108A and F153A toward palm stearin of high melting temperature made them potentially applicable in oil/fat modification. Our work provided an example to obtain biocatalysts with desired catalytic behaviors by protein engineering. [ABSTRACT FROM AUTHOR]

Background: Membrane sweeping (MS) could increase the likelihood of spontaneous labor within 48 h. However, the rationale for performing routinely an intervention with the potential to induce labor in women with an uneventful pregnancy at 38 weeks of gestation is, at least, questionable. We conducted a meta-analysis of randomized controlled trial (RCT) studies to assess evaluated the effect of MS added to formal induction method on the spontaneous vaginal delivery, compared with formal induction alone.Methods: PubMed, Embase, Cochrane Library databases, Web of Science, and Clinical Trials were searched from their inception to March 8, 2017. We estimate summarized relative risk (RR) and 95% confidence intervals (CIs) for dichotomous outcomes. The primary outcome was vaginal delivery, and second outcomes (side effects of MS) included meconium-stained liquor, admission to the neonatal unit, instrumental delivery.Results: Four RCTs with a total of 1377 participants were identified. The summary RR in the overall group was 1.12 (95% CI 1.05-1.18), with moderate heterogeneity (P = 0.22, I2 = 33%). The summary RR in the nulliparas' subgroup was 1.32 (95% CI 1.18-1.48), with no heterogeneity (P = 0.79, I2 = 0%). MS did not increase the risk of side effects.Conclusions: MS added to formal induction significantly increased vaginal delivery rates, especially in nulliparas compared with formal induction alone. Notably, there are no obvious side effects of MS. Meanwhile, more RCTs studies are needed to investigate the side effects of MS on instrumental delivery, postpartum hemorrhage, and cervical laceration. [ABSTRACT FROM AUTHOR]

HD-ZIP IV proteins belong to the homeodomain-leucine zipper (HD-ZIP) transcription factor family and are involved in trichome development and drought stress in plants. Although some functions of the HD-ZIP IV group are well understood in Arabidopsis, little is known about their function in cotton. In this study, HD-ZIP genes were identified from three Gossypium species ( G. arboreum, G. raimondii and G. hirsutum) and clustered into four families (HD-ZIP I, II, III and IV) to separate HD-ZIP IV from the other three families. Systematic analyses of phylogeny, gene structure, conserved domains, and expression profiles in different plant tissues and the expression patterns under osmotic stress in leaves were further conducted in G. arboreum. More importantly, ectopic overexpression of GaHDG11, a representative of the HD-ZIP IV family, confers enhanced osmotic tolerance in transgenic Arabidopsis plants, possibly due to elongated primary root length, lower water loss rates, high osmoprotectant proline levels, significant levels of antioxidants CAT, and/or SOD enzyme activity with reduced levels of MDA. Taken together, these observations may lay the foundation for future functional analysis of cotton HD-ZIP IV genes to unravel their biological roles in cotton. [ABSTRACT FROM AUTHOR]

8-Oxoguanosine (8-oxoGuo), 8-oxo-2′-deoxyguanosine (8-oxo-dG) and 8-iso-prostaglandin F2α (8-iso-PGF2α) are widely used noninvasive and effective biomarkers of oxidative damage to RNA, DNA and lipids. These three compounds are usually analyzed with different methods because of their different polarity and MS detection modes. In this paper, a sensitive and rapid UHPLC-MS/MS method to determine 8-oxoGuo, 8-oxo-dG and 8-iso-PGF2α in human urine was developed in order to evaluate the oxidative damage of DNA, RNA and lipid peroxidation. With this method, 8-oxoGuo, 8-oxo-dG and 8-iso-PGF2α could be conveniently and separately eluted with different elution solvent on the same Agilent Bond C18 solid-phase column; the two obtained eluates are detected through two injections using the same HPLC column and mobile phase for the determination of 8-oxoGuo, 8-oxo-dG and 8-iso-PGF2α in positive and negative ESI mode, respectively. The limits of detection and quantitation of the three biomarkers approached to 0.04-0.17 ng mL and 0.13-0.57 ng mL, respectively. The intraday and interday precisions of all compounds were at most 10%. The method was applied to analyze urine samples from 40 smokers and 20 nonsmokers to evaluate the effect of cigarette smoking on oxidative stress. The results showed that concentrations of the three compounds in the urine of smokers are higher than those in nonsmokers, indicating the increased oxidative stress effect of smoking. [ABSTRACT FROM AUTHOR]

Jasmonates control many aspects of plant biological processes. They are important for regulating plant responses to various biotic and abiotic stresses, including drought, which is one of the most serious threats to sustainable agricultural production. However, little is known regarding how jasmonate ZIM-domain (JAZ) proteins mediate jasmonic acid signals to improve stress tolerance in cotton. This represents the first comprehensive comparative study of TIFY transcription factors in both diploid A, D and tetraploid AD cotton species. In this study, we identified 21 TIFY family members in the genome of Gossypium arboretum, 28 members from Gossypium raimondii and 50 TIFY genes in Gossypium hirsutum. The phylogenetic analyses indicated the TIFY gene family could be divided into the following four subfamilies: TIFY, PPD, ZML, and JAZ subfamilies. The cotton TIFY genes have expanded through tandem duplications and segmental duplications compared with other plant species. Gene expression profile revealed temporal and tissue specificities for TIFY genes under simulated drought conditions in Gossypium arboretum. The JAZ subfamily members were the most highly expressed genes, suggesting that they have a vital role in responses to drought stress. Over-expression of GaJAZ5 gene decreased water loss, stomatal openings, and the accumulation of HO in Arabidopsis thaliana. Additionally, the results of drought tolerance assays suggested that this subfamily might be involved in increasing drought tolerance. Our study provides new data regarding the genome-wide analysis of TIFY gene families and their important roles in drought tolerance in cotton species. These data may form the basis of future studies regarding the relationship between drought and jasmonic acid. [ABSTRACT FROM AUTHOR]

In this paper, a sensitive accurate method for the determination of heterocyclic aromatic amines (HAAs) in cigarette smoke has been developed and validated using solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry. A calibration curve was obtained with representative cigarette smoke using the standard addition method to compensate for matrix effects because the smoke of different cigarettes shows similar matrix effects. With this method, the accuracy of the method can be improved using a common analog of HAAs, which will greatly reduce the expense of using an isotope-labeled internal standard. Validation results showed that the method has high sensitivity (quantification limits of 0.08-0.56 ng cig), good reproducibility (RSD 6.37-9.31 %) and satisfactory recoveries (81.0-111 %). With this method, the emissions of HAAs in 30 commercial cigarette samples were analyzed and compared. [ABSTRACT FROM AUTHOR]

A high quality cDNA library was constructed from the brown alga Laminaria japonica, with the titer of 1.2×10 pfu/ml. The average insert size of the cDNA library is about 1.6 kb. From the cDNA library, 591 cDNA clones were randomly selected and sequenced. As a result, 574 EST (expressed sequence tag) sequences were generated. All of the 574 ESTs were submitted to the dbEST database section of GenBank with the accession numbers from CX942625 to CX943198. The cDNA library was screened with a α-p labeled 453 bp TPS gene probe, which is a partial sequence yielded from Porphyra yezoensis. Four positive cDNA clones were screened and the sequencing data showed that these four cDNA clones covered majority of L. japonica TPS cDNA sequence. After PCR amplification, sequencing and assembling, the entire ORF (open reading frame) sequence of the TPS gene was obtained, which was named LjTPS. LjTPS encodes a protein containing 908 amino acids with a calculated molecular mass of 101 674 Daltons. The LjTPS gene was successfully expressed in E. coli and rice. The LjTPS gene has potential application both in plant breeding to stress tolerance and in deciphering the TPS gene function and mechanism to stress tolerance. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the therapeutic effect of deep anterior lamellar keratoplasty (DALK) in patients with herpetic stromal keratitis (HSK). Methods: Forty-three eyes belonging to 42 patients with HSK, including 22 eyes in the active phase and 21 eyes in the quiescent phase, underwent DALK at the Shandong Eye Institute from January 2006 to December 2009. All patients with active disease had received intravenous acyclovir and amniotic membrane implants prior to DALK. Herpes simplex virus type 1 (HSV-1) antigens from excised corneal buttons were detected by immunohistochemistry. Results: The follow-up ranged from 1 to 4 years (mean, 29.1 months). Graft rejection occurred in one eye (2.3%) and was reversed. Among the other 42 survived grafts (97.7%), 37 remained clear at the last visit. The best spectacle-corrected visual acuity was 20/200 or better in 95.2% of eyes and 20/40 or better in 38.1% of eyes. Six eyes (14.0%) developed recurrent HSK, one of which received a second keratoplasty due to ineffective antiviral medication. There were no significant differences in endothelial cell density between 6 months and 12 months after the surgery. By immunohistochemistry, HSV-1 antigens were observed in the stroma of 18 of 32 corneal buttons. Conclusions: DALK can not only remove the corneal lesions of HSK but also reduce latent or persistent viral loads in the cornea. In eyes with active or quiescent HSK but otherwise healthy endothelia, DALK seems to be safe and promising for its favorable visual outcome, graft survival rate, and low endothelial cell loss. [ABSTRACT FROM AUTHOR]

It has been reported that exposure to infrasound causes cardiac dysfunction. Allowing for the key role of apoptosis in the pathogenesis of cardiovascular diseases, the objective of this study was to investigate the apoptotic effects of infrasound. Cardiac myocytes cultured from neonatal rats were exposed to infrasound of 5 Hz at 130 dB. The apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. Also, the expression levels of a series of apoptosis-related proteins were detected. As a result, infrasound induced apoptosis of cultured rat cardiac myocytes in a time-dependant manner. The expression of proapoptotic proteins such as Bax, caspase-3, caspase-8, caspase-9, and FAS was significantly up-regulated, with concomitant down-regulated expression of antiapoptotic proteins such as Bcl-x, and the inhibitory apoptosis proteins family proteins including XIAP, cIAP-1, and cIAP-2. The expression of poly (ADP-ribose) polymerase and β-catenin, which are the substrate proteins of caspase-3, was significantly decreased. In conclusion, infrasound is an apoptotic inducer of cardiac myocytes. [ABSTRACT FROM AUTHOR]

The interactions between solute atoms and crystalline defects such as vacancies, dislocations, and grain boundaries are essential in determining alloy properties. Here we present a general linear correlation between two descriptors of local electronic structures and the solute-defect interaction energies in binary alloys of body-centered-cubic (bcc) refractory metals (such as W and Ta) with transition-metal substitutional solutes. One electronic descriptor is the bimodality of the d-orbital local density of states for a matrix atom at the substitutional site, and the other is related to the hybridization strength between the valance sp- and d-bands for the same matrix atom. For a particular pair of solute-matrix elements, this linear correlation is valid independent of types of defects and the locations of substitutional sites. These results provide the possibility to apply local electronic descriptors for quantitative and efficient predictions on the solute-defect interactions and defect properties in alloys. Understanding the interactions between solute atoms and crystalline defects is essential for determining alloy properties. Here the authors use a linear regression model to propose a quantitative correlation between local electronic structure descriptors and the solute-defect interaction energies in bcc refractory alloys. [ABSTRACT FROM AUTHOR]

Target of rapamycin (TOR) acts as an important regulator of cell growth, development and stress responses in most examined diploid eukaryotes. However, little is known about TOR in tetraploid species such as cotton. Here, we show that TORC1-S6K-RPS6, the major signaling components, are conserved and further expanded in cotton genome. Though the cotton seedlings are insensitive to rapamycin, AZD8055, the second-generation inhibitor of TOR, can significantly suppress the growth in cotton. Global transcriptome analysis revealed that genes associated with jasmonic acid (JA) biosynthesis and transduction were significantly altered in AZD8055 treated cotton seedlings, suggesting the potential crosstalk between TOR and JA signaling. Pharmacological and genetic approaches have been employed to get further insights into the molecular mechanism of the crosstalk between TOR and JA. Combination of AZD8055 with methyl jasmonate can synergistically inhibit cotton growth, and additionally JA levels were significantly increased when cotton seedlings were subjected to AZD8055. JA biosynthetic and signaling mutants including jar1, coi1-2 and myc2-2 displayed TOR inhibitor-resistant phenotypes, whereas COI1 overexpression transgenic lines and jaz10 exhibited sensitivity to AZD8055. Consistently, cotton JAZ can partially rescue TOR-suppressed phenotypes in Arabidopsis. These evidences revealed that the crosstalk between TOR and JA pathway operates in cotton and Arabidopsis. [ABSTRACT FROM AUTHOR]