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Abstract Background One of the challenges of physical training in extreme condition is frostbite, especially in Northeast China. In this study, we aimed to construct a risk prediction model for frostbite among soldiers in Northeast China, and verify its effect. Methods 698 participants were selected via convenience sampling from Northeast China from December 2021 to January 2022 (winter). They were randomly divided into a training set (N = 479) and a testing set (N = 202) in a ratio of 7:3. All participants completed a researcher-made questionnaire on frostbite. The prediction model was constructed through the use of Logistic regression analysis, which was used to predict the independent risk factors for frostbite formation and screen significant indicators. The model’s performance was assessed using the receiver operating characteristic (ROC) curve and decision curve analysis (DCA) to evaluate the prediction efficiency and goodness of fit. Results The incidence of frostbite in the training set was 19.83% (95 people), all of which were first-degree frostbite. Among them, frostbite in multiple parts was the most common (58.95%), followed by singular body parts like hands (24.21%), ears (11.58%) and feet (5.26%). Single factor logistic regression analyses showed that ambient temperature, ambient wind speed, outdoor stationary time, stationary status, and history of frostbite are independent risk factors that affect the occurrence of frostbite. Furthermore, we constructed the frostbite risk prediction model for soldiers in the northeastern region of China. The area under the receiver operating characteristic curve (AUC) for the risk of frostbite in the training set and testing set was 0.816 (95% CI, 0.770 ~ 0.862) and 0.787 (95% CI, 0.713 ~ 0.860), respectively. The Hosmer-Lemeshow test of the model showed χ 2 = 11.328 and P = 0.184 (> 0.05). The DCA curve indicated that most of the clinical net benefits of the model are greater than 0, demonstrating good clinical usefulness. Conclusion The constructed frostbite prediction model can effectively identify soldiers with a higher risk of frostbite. It provided theoretical support for commanders to take preventive measures to reduce the incidence of frostbite among soldiers and was of great clinical guiding significance.

BackgroundMyopia, strabismus, and ptosis are common pediatric eye diseases, which have a negative impact on children and adolescents in terms of visual function, mental health, and health-related quality of life (HRQoL). Therefore, this study focused on those pediatric eye diseases by analyzing their risk factors and HRQoL for the comprehensive management of myopia, strabismus, and ptosis.MethodsA total of 363 participants (2–18 years old) were included in this study for risk factors analysis of myopia, strabismus, and ptosis. We collected demographic characteristics, lifestyle habits and eye care habits of these children and analyzed them by using univariable and multivariable logistic regression. In addition, we applied the Chinese version of Pediatric Quality of Life Inventory-Version 4.0 (PedsQL 4.0) to assess HRQoL in 256 children with strabismus and ptosis. Univariable and multivariable linear regression models were applied to evaluate potential influencing factors of HRQoL.ResultsOf all the participants, 140 had myopia, 127 had strabismus, and 145 had ptosis. Based on the multivariable logistic regression analysis model, we found that the history of parental myopia and daily average near-distance eye usage time were risk factors for myopia, and increased body mass index (BMI) was identified as a risk factor for strabismus and ptosis. Individuals with ptosis possessed decreased HRQoL. The multivariable linear regression model suggested that daily average near-distance eye usage time, light intensity during visual tasks, and daily average sleep duration had potential influences on HRQoL.ConclusionThis is the first study to assess the risk factors and HRQoL of myopia, strabismus, and ptosis together. We identified risk factors for these common pediatric eye diseases to help doctors, parents, and teachers better manage them. Our study discovered that children with eye disorders exhibit a notably diminished HRQoL. Consequently, it emphasizes the necessity for increased social attention and mental health assistance for these children.

In this study, different proportions of curcumin (CUR) and alizarin (ALI) were added to konjac glucomannan (KG)/ polyvinyl alcohol (PVA) to prepare an active intelligent packaging film and evaluate its potential to indicate pork freshness. The mixed indicator had a richer color hierarchy in the buffer solution with pH = 2–12. The surface of the KG-2C2A and KG-1C3A films is smoother and has fewer cross-section faults. With the increase of CUR content in the film, the crystal structure becomes more prominent, leading to poor compatibility with KG. The WAC of KG-3C1A and KG-1C3A films was significantly higher than that of the other groups, and they had better hydrophobicity. With the increase of CUR content in the films, the thermal stability of the films was enhanced, and the KG-C films showed the highest thermal stability. Among them, the KG-2A2C and KG-1C3A films showed the most significant color change during pork spoiling and could be used to monitor the freshness of pork. As a pH colorimetric indicator, CUR and ALI-coated KG films might be of great potential in fresh meat monitoring.

Choroidal neovascularization (CNV), characterized as a prominent feature of wet age-related macular degeneration (AMD), is a primary contributor to visual impairment and severe vision loss globally, while the prevailing treatments are often unsatisfactory. The development of conventional treatment strategies has largely been based on the understanding that the angiogenic switch of endothelial cells is dictated by angiogenic growth factors alone. Even though treatments targeting vascular endothelial growth factor (VEGF), like Ranibizumab, are widely administered, more than half of the patients still exhibit inadequate or null responses, emphasizing the imperative need for solutions to this problem. Here, aiming to explore therapeutic strategies from a novel perspective of endothelial cell metabolism, a biocompatible nanomedicine delivery system is constructed by loading RGD peptide-modified liposomes with 2-deoxy-D-glucose (RGD@LP-2-DG). RGD@LP-2-DG displayed good targeting performance towards endothelial cells and excellent in vitro and in vivo inhibitory effects on neovascularization were demonstrated. Moreover, our mechanistic studies revealed that 2-DG interfered with N-glycosylation, leading to the inhibition of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream signaling. Notably, the remarkable inhibitory effect on neovascularization and biocompatibility of RGD@LP-2-DG render it a highly promising and clinically translatable therapeutic candidate for the treatment of wet AMD and other angiogenic diseases, particularly in patients who are unresponsive to currently available treatments.

Harmonic amplification phenomena could appear at the point of common connection (PCC) of the cable line terminal. However, the distributed parameter model of the cable line contains hyperbolic functions with plural variables, which makes it challenging to obtain the harmonic amplification factor (HAF). Hence, a time-domain method combining the Kalman filter and convolution inversion (KFCI) methods is proposed to address this problem. First, the Kalman filter method optimizes the square wave pulse response (SWPR) with measurement error. Then, the optimized SWPR data are used to get the HAF by the convolution inversion method. Next, the harmonic amplification characteristics of cable lines are explored. Finally, an experimental simulation model is built on the PSCAD software, verifying the optimization effectiveness of Kalman filter for the SWPR with error and the accuracy of the HAF calculated by the proposed method. The analysis rationality of harmonic amplification properties is also demonstrated.

Abstract Estimation of harmonic impedances and harmonic contributions is beneficial to harmonic control, and harmonic phasors data is necessary for the existing estimation methods. However, the phase angles of harmonic phasors are not recorded in some of current power quality measuring instruments (such as Fluke 1760 etc.), which makes the existing methods unavailable. To solve this problem, the Norton equivalent circuit model under harmonic frequency is improved and a new model composed of harmonic complex power sources and harmonic impedances is proposed. Based on the model, the harmonic impedance and harmonic contribution can be estimated by using independent component analysis algorithm, and the harmonic phasor data is no longer required. The superiority of the proposed model is verified through simulation and field cases.

It is well-known that thermocapillary-buoyancy flow instability can be affected by several dimensionless control parameters. The general relationships among them are helpful for actively controlling flow instability but were not clear. This work reported some experiments in the annular pool with a radius ratio of 0.25, and proposed the general relationships among these dimensionless control parameters, especially for the critical Marangoni number of the flow destabilization and the dimensionless oscillatory frequency of pulsating pattern. Combined with previous studies, these general relationships are achieved within no more than 15% relative deviations, whose applicability is for the thermocapillary-buoyancy flow of medium Prandtl number fluids in side-heated annular pools. Based on the experimental findings, we can confirm that the flow destabilization can be suppressed by buoyancy. The steady multicellular flow appears before flow destabilization. When the flow is destabilized, the pulsating pattern first appears, and then a superimposition of the pulsating pattern and the flower-like wave.

Background: Core training can enhance athletic performance by enhancing core strength and stability. To achieve this outcome, however, a tailored training program is required; the normal military training curriculum is inadequate. The connection between cumulative weekly extracurricular training time, cumulative weekly extracurricular core training time and cadet performance is unknown. Methods: The association between cumulative weekly extracurricular training time, cumulative weekly extracurricular core training time and performance has been discovered using a descriptive epidemiological study methodology. Questionnaires were used to collect information on personal characteristics and weekly cumulative extracurricular (core) training time, as well as the results of the Chinese Army Physical Fitness Test (C-APFT), which included 100-m dash, 5000-m run, 3000-m armed training run, 400-m steeplechase, 800 m breaststroke, horizontal bar pull-ups, 2-min sit-ups, 2-min push-ups, and hand grenade throwing. This study recruited two hundred and twenty male cadets (aged 18 to 23 years, 19.68 ± 0.91) from a military medical university. Results: (a) The correlation between cumulative weekly extracurricular training time and C-APFT score is significant. The 100-m dash, 5000-m run, 3000-m armed training run, 400-m steeplechase, and 2-min push-ups performed the best when participants exercised for 5 to 10 h per week. (b) The number of cadets scoring good or excellent on the C-APFT improves with cumulative weekly extracurricular core training time. The recommended amount of core training for cadets per week is 120 min. (c) The average cumulative weekly extracurricular core training time was a effective predictor of performance on the 400-m steeplechase (R2 = 0.470, F = 10.641, P＜0.01), horizontal bar pull-ups (R2 = 0.238, F = 68.191, P＜0.01), 2-min sit-ups (R2 = 0.280, F = 84.710, P＜0.01), 100-m run (R2 = 0.031, F = 6.920, P＜0.01), 3000-m armed training run (R2 = 0.025, F = 5.603, P＜0.05), 2-min push-ups (R2 = 0.019, F = 4.295, P＜0.05), and hand grenade tossing (R2 = 0.025, F = 5.603, P＜0.05). Conclusions: Active participation in extracurricular core training can improve cadets' C-APFT scores. An average cumulative weekly extracurricular training duration of 5–10 h showed the most progress, and more than 120 min per week was ideal for extracurricular core training. The amount of extracurricular time spent on core training exercises each week can be used as a predictor of the C-APFT.

Abstract On‐line partial discharge (PD) monitoring is related to the safe and stable operation of power grid. However, the measured signal is inevitably affected by noise. Among a variety of noises, white noise is the most difficult to suppress and ubiquitous. It mainly determines the Cramer–Rao lower bound that cannot be crossed by all methods. This article proposes the Prony time‐series energy spectrum method to suppress white noise in a low signal‐to‐noise ratio environment. This method is divided into two parts: First, Prony time series energy spectrum is used to detect whether there is PD signals in the measured signal. Then, based on the least square method, the PD signal is estimated with the Prony model. In data analysis, this method can suppress ‐10dB white noise, while other methods have performed poorly or even failed under the same conditions. In general, this method has excellent anti‐noise performance compared to several other algorithms.

The ornamental gourd Cucurbita pepo L. is a ubiquitous crop native to North America, exhibiting highly diverse fruit characteristics. Studying the genetic diversity of ornamental gourds can help identify and evaluate the curated germplasm resources, understand the phylogenetic relationships among them, and highlight ways in which the germplasm resources can be used to address gaps in the understanding. In this study, a set of 85 of 323 previously identified polymorphic expressed sequence tag-simple sequence repeat (EST-SSR) genetic markers were selected to evaluate the genetic relationships among 47 C. pepo accessions and one C. foetidissima accession. This collection consisted of accessions from the subspecies pepo, texana, and the hybrid texana × pepo. Our analyses yielded a total of 271 alleles, with an average of 3.2 alleles per genetic locus. The dendrogram construction, principal coordinate analyses, and genetic value calculation revealed several robust subclusters in the texana subspecies accessions. From these results, we propose five new distinct morphotypes based on our construction of a concise SSR fingerprint. Moreover, our study confirms that the fruit shape similarity among accessions is a fair reflection of genetic relatedness.

Abstract For the communication systems, no‐hit‐zone (NHZ) frequency hopping sequences have good anti‐interference performance. However, the system's time delay may be out of the NHZ. In this situation, the maximum Hamming correlation is needed to be taken into consideration. When the maximum Hamming correlation of an optimal NHZ‐FHS set is minimal, the NHZ‐FHSs will be called strong NHZ‐FHSs. It is also hoped that FHSs have a wide gap property to resist the enemy's intentional interferences. In this letter, a tighter bound for optimal NHZ‐FHSs' maximum Hamming correlation is proposed and an optimal strong NHZ‐FHS set is constructed with widegap.

Abstract This study evaluated the water resource utilization efficiency and resource consumption for planting, forestry, animal husbandry, and fishery in various regions of China. Using the super-efficiency Slacks-Based Measure (SBM) analysis method, the main agricultural pollution emissions (Chemical Oxygen Demand, ammonia nitrogen, and agricultural carbon emissions) were proposed as environmental constraints for the first time. The threshold regression model was used to measure the impact of agricultural water use efficiency on agricultural water consumption by constructing seven different explanatory variables. The results show that the overall utilization efficiency of agricultural water resources in China presents a fluctuating downward trend, and the regional differences are significant. A single threshold effect on agricultural water consumption was found in five variables: per capita water resources, disposable income, dependence on foreign trade, industrial structure, and Gross Domestic Product. The increase in each parameter will have a positive effect on agricultural water consumption. The relationship between agricultural water use efficiency and agricultural water use was non-linear when the government's attention and the rural labor force were used as threshold variables.

In this paper, the Cauchy mixture distribution is used for rigid and affine registration. The Cauchy function has a wider effective range than the general window function, so it has a greater information utilization ratio than most registration algorithms. This means that the method can quickly match point clouds without initial registration and corresponding points. On the other hand, the computational complexity of Cauchy mixture model is lower than that of widely used Gaussian mixture model. This means that the introduction of Cauchy mixture model will save computing resources. However, the log-likelihood function of the Cauchy mixture distribution is a nonlinear function that is difficult to solve. This paper proposes an optimization method for the Cauchy mixture model, and discusses the advantages of the Cauchy mixture model in rigid and affine registration. In the experiment, compared with several other algorithms, our method quickly and accurately registers point clouds.

The detection process of partial discharge (PD) ultra-high frequency (UHF) signal is easily affected by white noise and periodic narrowband noise, which hinder the fault diagnosis of high-voltage electrical appliances. In order to extract PD UHF signal and suppress noise effectively, this paper provides a new method to detect PD UHF signal by EDSSV and low rank RBF neural network. Firstly, the singular value decomposition (SVD) is performed on the mixed noises of PD signal. Secondly, the peak index of energy difference spectrum of singular value (EDSSV) is selected as optimal singular value threshold, and then the periodic narrowband noise is eliminated by reconstructing the effective rank order. Finally, radial basis function (RBF) neural network is used to approximate the denoised PD signal, and Gaussian window filter is used to extract the PD signal. To verify the performance of the proposed method, we compared it with other three algorithms in simulation and field detection, including adaptive singular value decomposition (ASVD), singular value decomposition based on S-transform and MTFM (S-SVD) and EMD-WT algorithms. Particularly, four evaluation indices are designed for the detection data, which consider both the noise suppression and feature preservation. The results demonstrate the validity of the proposed method with higher signal-to-noise ratio and less waveform distortion.

Registering point clouds quickly and accurately has always been a challenging task. A lot of research based on Gaussian mixture model is widely used in recent years. However, few people use other models for point cloud matching. Therefore, this paper proposes a point cloud registration algorithm based on the Laplace mixture model. In this paper, sampling variance is used to replace the variance of the likelihood estimation to successfully overcome the nonlinear problem. In addition, the Laplace model has strong robustness, which is very suitable for point cloud matching of 3D laser scanning. In the experiment, compared with several other algorithms, proposed method quickly and accurately registers point clouds.

ABSTRACT Listeria monocytogenes is a major pathogen contributing to foodborne outbreaks with high mortality. Nisin, a natural antimicrobial, has been widely used as a food preservative. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. A mariner transposon library was constructed in L. monocytogenes, leading to the identification of 99 genes associated with the innate resistance to nisin via Transposon sequencing (Tn-seq) analysis. To validate the accuracy of the Tn-seq results, we constructed five mutants (ΔyqgS, ΔlafA, ΔvirR, ΔgtcA, and Δlmo1464) in L. monocytogenes. The results revealed that yqgS and lafA, the lipoteichoic acid-related genes, were essential for resistance to nisin, while the gtcA and lmo1464 mutants showed substantially enhanced nisin resistance. Densely wrinkled, collapsed surface and membrane breakdown were shown on ΔyqgS and ΔlafA mutants under nisin treatment. Deletion of yqgS and lafA altered the surface charge, and decreased the resistance to general stress conditions and cell envelope-acting antimicrobials. Furthermore, YqgS and LafA are required for biofilm formation and cell invasion of L. monocytogenes. Collectively, these results reveal novel mechanisms of nisin resistance in L. monocytogenes and may provide unique targets for the development of food-grade inhibitors for nisin-resistant foodborne pathogens. IMPORTANCE Listeria monocytogenes is an opportunistic Gram-positive pathogen responsible for listeriosis, and is widely present in a variety of foods including ready-to-eat foods, meat, and dairy products. Nisin is the only licensed lantibiotic by the FDA for use as a food-grade inhibitor in over 50 countries. A prior study suggests that L. monocytogenes are more resistant than other Gram-positive pathogens in nisin-mediated bactericidal effects. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. Here, we used a mariner transposon library to identify nisin-resistance-related genes on a genome-wide scale via transposon sequencing. We found, for the first time, that YqgS and LafA (Lipoteichoic acid-related proteins) are required for resistance to nisin. Subsequently, we investigated the roles of YqgS and LafA in L. monocytogenes stress resistance, antimicrobial resistance, biofilm formation, and virulence in mammalian cells.

The accurate estimation of harmonic impedance on the utility side of a point of common coupling (PCC) is much important to harmonic control, harmonic emission level, and harmonic responsibility analysis. In this study, a novel estimation method for the utility harmonic impedance is proposed, which employs the Gaussian mixed model (GMM) to fit the measured data at a PCC, because the authors find that the statistical distribution of the measured data at a PCC is close to the Gaussian distribution. Also, in theory, GMM can approach the probability distribution of any data. In this method, the Norton equivalent circuit model at a PCC is first expressed as a GMM, and the utility harmonic impedance in the GMM is estimated by expectation maximisation iterative method. Compared to the existing estimation methods, an outstanding advantage of this method is that it is less affected by background harmonics; therefore, higher accuracy can be acquired in this method. The effectiveness and accuracy of this method are verified by simulation experiments and field data.

Abstract Background Poor sleep quality negatively affects the readiness of military operations and is also associated with the development of mental health disorders and decreased quality of life. The purpose of this study was to investigate the sleep quality of military personnel from remote boundaries of China and its relationship with coping strategies, anxiety, and health-related quality of life (HRQoL). Methods A cross-sectional survey was performed among military officers and soldiers from a frontier defence department and an extreme cold environment. The participants were surveyed using the Pittsburgh Sleep Quality Index (PSQI), Trait Coping Style Questionnaire (TCSQ), Self-rating Anxiety Scale (SAS), and Short Form Health Survey (SF-36). Results A total of 489 military officers and soldiers were included. The participants had a mean age of 22.29 years. The median overall PSQI score was 7.0 (IQR, 4.0 ~ 9.0), with 40.9% (200/489) of the subjects reporting poor sleep quality. The difficulties with sleep were mainly related to daytime dysfunction due to disrupted sleep, sleep latency, and subjective sleep quality. The median score of the SF-36 physical component was 83.5 (IQR, 73.0 ~ 90.5), and the median score of the mental component was 74.1 (IQR, 60.4 ~ 85.1). Significant correlations were found between the PSQI and SF-36 (r = − 0.435, P

The existing methods for estimating harmonic impedance usually assume that harmonic impedance is constant in a measurement period. However, for a variety of practical reasons, such as the load change of power grid, utility harmonic impedance may be changed. So a reasonable hypothesis is that utility harmonic impedance is time-varying, but the variation of the impedance is not large at adjacent sampling time. Thus, this paper proposes a novel method to estimate utility harmonic impedance by taking the criterion of minimum norm of impedance differences at adjacent sampling times with a measurement period. According to the proposed criterion, an objective function is built with the norm of the harmonic impedance differences and utility harmonic voltage differences of adjacent moments. And then, the utility harmonic impedance can be obtained by minimizing the objective function. The proposed method has high accuracy even while background harmonic emission level is high and harmonic impedance of customer side is not much larger than that of utility side. The effectiveness is verified by the simulation and field cases. In the simulation, the estimation errors of most cases are within 10% and the maximum error is not exceed 16%.

With the large increase of the wide-frequency and high-order harmonic in power electronic based systems as well as the wide use of cables with large distributed capacitance in modern power grids especially renewable energy generations, the harmonic amplification in cables becomes a serious problem. Some researchers have paid attention to this problem, but the quantitative relationship between harmonic amplification and cable length has not been determined, which is studied in this paper to cover the shortage. First, the influence factors of harmonic amplification are converted into two rotation phasors. These factors, including cable parameters, harmonic frequency and equivalent harmonic impedance of power system, are converted into the initial amplitude, phase and angular frequency of the rotation phasors. Then, the solution of harmonic amplification factor (HAF) is converted to solve the reciprocal of the amplitude of the sum of the two rotation phasors. With the cosines law, HAF and the cable length segments where harmonic exceeds the limit can be figured out quantitatively. The analysis method and conclusions proposed can help to guide cable length planning for avoiding harmonic exceeding the limit or to analyze the cause of harmonic exceeding the limit. Correctness and effectiveness are verified by the simulation and field cases.

To enhance the nutritional value of highland barley (HB), this work investigated the effects of solid-state fermentation (SSF) by Agaricus sinodeliciosus var. Chaidam ZJU-TP-08 on nutrient content, phenolic components, antioxidant activities, and physicochemical characteristics of HB upon different pretreatments (germination, ultrasound and soaking). The results showed that germinated highland barley (GHB) exhibited higher levels of ergosterol (0.19 ± 0.01 mg/g) in all fermentation groups. The content of β-glucan was higher in the SSF-GHB, with an increase of 24.21% compared to the control. The content of total amino acids, dietary fiber, total phenols and flavonoids were higher in the fermentation HB pretreated by ultrasound, increasing respectively by 5.60%, 61.50%, 25.10% and 65.32% compared to the control group. In addition, the colonized HB exhibited excellent physicochemical characteristics, including increased water solubility index and decreased pasting characteristics. Herein, the nutritional value and the biological activities were enriched in the pretreated HB through SSF, indicating its potential application for nutrition-enriched functional foods.

Methicillin-resistant Staphylococcus aureus (MRSA) is drug-resistant and biofilm-forming pathogenic bacteria with severe morbidity and mortality, and has been continuously detected in food products in recent years. Mannosylerythritol lipids (MELs) are novel biosurfactants and perform antibacterial property against gram-positive bacteria. Ultrasound has been applied into food sterilization as non-thermal techniques and has advantage of maintaining food nutrition and flavor over heat pasteurization. In this work, the synergistic treatment of ultrasound and MEL-A was used to combat planktonic cells and biofilm of MRSA. As a result, the combined treatment has exhibited remarkable antibacterial effect proved by enumeration of viable microbes. Furthermore, flow cytometry, scanning electron microscopy and transmission electron microscopy revealed ultrasound has enhanced the inhibitory effect of MEL-A through exacerbating cell membrane damage. On the other hand, the collaborating working modes to eradicate MRSA biofilm were disturbing cell adhesion to surface by MEL-A and destructing mature biofilm mechanically by ultrasound, reaching to over 90% of clearance rate. The findings of this study illustrated the synergistic antimicrobial mechanism of ultrasound and MEL-A treatments, and offered theoretical basis for their potential applications in food preservation.

For a quasi-synchronous frequency/time hopping (FH/TH) code-division multiple-access (CDMA) system which involves many users, the low-hit-zone (LHZ) FH/TH sequence set with large family size is necessary. In this paper, an upper bound on the family size of LHZ FH/TH sequence sets is derived. The new bound includes the Singleton bound on FH sequence sets as a special case. Further, three constructions of LHZ FH/TH sequence sets are presented, which have optimal/near optimal family size and also optimal maximum Hamming correlation (MHC) with respect to the new bound. They have very large family size compared with the known LHZ FH/TH sequence sets in the literature.

A novel phosphaphenanthrene oxide PN-DOPO, based on bridged 9,10-dihrdro-9-oxa-10-phosphaphenamhrene-10-oxide (DOPO) and acetophenone was synthesized and the structure of product was characterized by FT-IR,1H-NMR,31P-NMR and MS. Glass fiber reinforced high temperature polyamide (GFPA6T/FR) composites, was prepared by incorporating the product (PN-DOPO) and aluminum diethyl-hypophosphite (OP1230) incorporated as flame retardant additives, GFPA6T/FR samples were characterized and analyzed by vertical burning test (UL-94), cone calorimeter, TGA, SEM and dynamic mechanical analysis (DMA) test. The results show that the addition of PN-DOPO and OP1230 can reduce the combustion level. GFPA6T/PN-DOPO reaches FV-0 level when the amount of PN-DOPO is 17.5%(mass fraction). HRR and THR of GFPA6T/PN-DOPO decrease more significantly than those of GFPA6T/OP1230, residual amount of thermal degradation is higher and char forming is more obvious. The results of DMA show that FR promotes micro cross-linking with PA6T molecular chain, leading to the increase of the rigidity of matrix. The results show that PN-DOPO is more significant than OP1230 in improving the flame retardancy and maintaining mechanical properties of GFPA6T.

Background/Aims: Chronic renal failure (CRF) is often accompanied by increased oxidative stress and euthyroid sick syndrome (ESS). The cause of ESS is unknown, and it is unknown whether there exists a link between oxidant stress and ESS in CRF patients. Therefore, we aim to investigate oxidative stress and type 1 deiodinase (DIO1) expression, which plays the key role in the ESS in CRF patients. Methods: In-patients with CRF were divided into the two group: Group 1 is ESS patients consisting of 60 patients with low free triiodothyronine (FT3) and Group 2 consisting of 60 patients with normal FT3. Group 3 consisted of 60 healthy volunteers recruited as controls. The baseline clinical parameters of patients were evaluated with standard routine methods in a clinical laboratory. Serum levels of 8-isoprostane and DIO1 were measured by enzyme-linked immunosorbent assay (ELISA). Multiple regression analysis was used to analyze the relationship between oxidative stress, DIO1 and FT3. Results: The concentrations of serum 8-Isoprostane in Group 1 and Group 2 were substantially higher than that of Group 3 (p< 0.05), however there was no significant difference between Group 1 and Group 2 (p=0.516). The serum DIO1 level was higher in Group 2 than in Group 1 and Group 3 (p< 0.001). Multivariate linear regression analysis revealed that the DIO1 concentration and FT3 level were not associated with the concentration of serum 8-Isoprostane. Conclusions: CRF patients showed elevated oxidative stress. The CRF patients without ESS showed higher expression of DIO1 than patients with ESS and the control group. The concentration of serum 8-Isoprostane was not correlated with FT3 and DIO1 levels.

Point clouds scanned by three-dimensional lasers may be multidirectional affine transformed when the specifications for the products, laser scanners, and thermal expansion are incompatible. If a point cloud is out of order in such a case, many existing algorithms may not be suitable to solve the problem. Therefore, this paper proposes a multidirectional affine registration (MDAR) algorithm based on the statistical characteristics and shape features of point clouds. First, we transform the problem into a problem of finding certain matrix eigenvalues. In addition, the similarity of the global vector features is introduced, and the scaling factor is calculated by maximizing the similarity. Finally, using the estimated affine factors, the multidirectional affine registration is transformed into a rigid registration. Simulation results show that the MDAR algorithm has better accuracy and less time consumption than several existing algorithms.

Seed coat color is an important agronomic trait of edible seed pumpkin in Cucurbita maxima. In this study, the development pattern of seed coat was detected in yellow and white seed coat accessions Wuminglv and Agol. Genetic analysis suggested that a single recessive gene white seed coat (wsc) is involved in seed coat color regulation in Cucurbita maxima. An F2 segregating population including 2798 plants was used for fine mapping and a candidate region containing nine genes was identified. Analysis of 54 inbred accessions revealed four main Insertion/Deletion sites in the promoter of CmaCh15G005270 encoding an MYB transcription factor were co-segregated with the phenotype of seed coat color. RNA-seq analysis and qRT-PCR revealed that some genes involved in phenylpropanoid/flavonoid metabolism pathway displayed remarkable distinction in Wuminglv and Agol during the seed coat development. The flanking InDel marker S1548 was developed to predict the seed coat color in the MAS breeding with an accuracy of 100%. The results may provide valuable information for further studies in seed coat color formation and structure development in Cucurbitaceae crops and help the molecular breeding of Cucurbita maxima.

Glycolipid biosurfactants are natural amphiphiles and have gained particular interest recently in their biodegradability, diversity, and bioactivity. Microbial infection has caused severe morbidity and mortality and threatened public health security worldwide. Glycolipids have played an important role in combating many diseases as therapeutic agents depending on the self-assembly property, the anticancer and anti-inflammatory properties, and the antimicrobial properties, including antibacterial, antifungal, and antiviral effects. Besides, their role has been highlighted as scavengers in impeding the biofilm formation and rupturing mature biofilm, indicating their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction in vast hospital infections. Notably, glycolipids have been widely applied to the synthesis of novel antimicrobial materials due to their excellent amphipathicity, such as nanoparticles and liposomes. Accordingly, this review will provide various antimicrobial applications of glycolipids as functional ingredients in medical therapy.

Foreign object debris (FOD) on airport runways can cause serious accidents and huge economic losses. FOD detection systems based on millimeter-wave (MMW) radar sensors have the advantages of higher range resolution and lower power consumption. However, it is difficult for traditional FOD detection methods to detect and distinguish weak signals of targets from strong ground clutter. To solve this problem, this paper proposes a new FOD detection approach based on optimized variational mode decomposition (VMD) and support vector data description (SVDD). This approach utilizes SVDD as a classifier to distinguish FOD signals from clutter signals. More importantly, the VMD optimized by whale optimization algorithm (WOA) is used to improve the accuracy and stability of the classifier. The results from both the simulation and field case show the excellent FOD detection performance of the proposed VMD-SVDD method.

Mannosylerythritol lipids-A (MEL-A) is a novel biosurfactant with excellent surface activity and potential biomedical applications. In this study, we explored the antibacterial activity and the underlying mechanisms of MEL-A against the important food-borne pathogen Listeria monocytogenes. The bacterial growth and survival assays revealed a remarkable antibacterial activity of MEL-A. Since MEL-A is a biosurfactant, we examined the cell membrane integrity and morphological changes of MEL-A-treated bacteria by biochemical assays and flow cytometry analysis and electron microscopes. The results showed obvious damaging effects of MEL-A on the cell membrane and morphology. To further explore the antibacterial mechanism of MEL-A, a transcriptome analysis was performed, which identified 528 differentially expressed genes (DEGs). Gene ontology (GO) analysis revealed that the gene categories of membrane, localization and transport were enriched among the DEGs, and the analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways demonstrated significant changes in the maltodextrin ABC transporter system and stress response system. Furthermore, the growth of L. monocytogenes could also be significantly inhibited by MEL-A in milk, a model of a real food system, suggesting that MEL-A could be potentially applied as an natural antimicrobial agent to control food-borne pathogens in the food industry.

ABSTRACT Curli amyloid fibers are produced as part of the extracellular biofilm matrix and are composed primarily of the major structural subunit CsgA. The CsgE chaperone facilitates the secretion of CsgA through CsgG by forming a cap at the base of the nonameric CsgG outer membrane pore. We elucidated a series of finely tuned nonpolar and charge-charge interactions that facilitate the oligomerization of CsgE and its ability to transport unfolded CsgA to CsgG for translocation. CsgE oligomerization in vitro is temperature dependent and is disrupted by mutations in the W48 and F79 residues. Using nuclear magnetic resonance (NMR), we identified two regions of CsgE involved in the CsgE-CsgA interaction: a head comprising a positively charged patch centered around R47 and a stem comprising a negatively charged patch containing E31 and E85. Negatively charged residues in the intrinsically disordered N- and C-terminal “tails” were not implicated in this interaction. Head and stem residues were mutated and interrogated using in vivo measurements of curli production and in vitro amyloid polymerization assays. The R47 head residue of CsgE is required for stabilization of CsgA- and CsgE-mediated curli fiber formation. Mutation of the E31 and E85 stem residues to positively charged side chains decreased CsgE-mediated curli fiber formation but increased CsgE-mediated stabilization of CsgA. No single-amino-acid substitutions in the head, stem, or tail regions affected the ability of CsgE to cap the CsgG pore as determined by a bile salt sensitivity assay. These mechanistic insights into the directed assembly of functional amyloids in extracellular biofilms elucidate possible targets for biofilm-associated bacterial infections. IMPORTANCE Curli represent a class of functional amyloid fibers produced by Escherichia coli and other Gram-negative bacteria that serve as protein scaffolds in the extracellular biofilm matrix. Despite the lack of sequence conservation among different amyloidogenic proteins, the structural and biophysical properties of functional amyloids such as curli closely resemble those of amyloids associated with several common neurodegenerative diseases. These parallels are underscored by the observation that certain proteins and chemicals can prevent amyloid formation by the major curli subunit CsgA and by alpha-synuclein, the amyloid-forming protein found in Lewy bodies during Parkinson’s disease. CsgA subunits are targeted to the CsgG outer membrane pore by CsgE prior to secretion and assembly into fibers. Here, we use biophysical, biochemical, and genetic approaches to elucidate a mechanistic understanding of CsgE function in curli biogenesis.

In this work, using Saccharomyces cerevisiae as a model, we showed that BetA could inhibitcell proliferation and lead to lethal cytotoxicity accompanying programmed cell death (PCD).Interestingly, it was found that vacuolar protease Pep4p played a pivotal role in BetA‐induced S.cerevisiae PCD. The presence of Pep4p reduced the damage of BetA‐induced cells. This work impliedthat BetA may induce cell death of S. cerevisiae through mitochondria‐mediated PCD, and thedeletion of Pep4 gene possibly accelerated the effect of PCD. The present investigation provided thepreliminary research for the complicated mechanism of BetA‐induced cell PCD regulated by vacularprotease Pep4p and lay the foundation for understanding of the Pep4p protein in an animal model.

As a novel natural compound delivery system, liposomes are capable of incorporating lipophilic bioactive compounds with enhanced compound solubility, stability and bioavailability, and have been successfully translated into real-time clinical applications. To construct the soy phosphatidylcholine (SPC)−cholesterol (Chol) liposome system, the optimal formulation was investigated as 3:1 of SPC to Chol, 10% mannosylerythritol lipid-A (MEL-A) and 1% betulinic acid. Results show that liposomes with or without betulinic acid or MEL-A are able to inhibit the proliferation of HepG2 cells with a dose-effect relation remarkably. In addition, the modification of MEL-A in liposomes can significantly promote cell apoptosis and strengthen the destruction of mitochondrial membrane potential in HepG2 cells. Liposomes containing MEL-A and betulinic acid have exhibited excellent anticancer activity, which provide factual basis for the development of MEL-A in the anti-cancer applications. These results provide a design thought to develop delivery liposome systems carrying betulinic acid with enhanced functional and pharmaceutical attributes.

Vacuolar proteinase A (Pep4p) is required for the post-translational precursor maturation of vacuolar proteinases in Saccharomyces cerevisiae, and important for protein turnover after oxidative damage. The presence of proteinase A in brewing yeast leads to the decline of beer foam stability, thus the deletion or inhibition of Pep4p is generally used. However, the influence of Pep4p deletion on cell metabolism in Saccharomyces cerevisiae is still unclear. Herein, we report the identification of differentially down-regulated metabolic proteins in the absence of Pep4p by a comparative proteomics approach. 2D-PAGE (two-dimensional polyacrylamide gel electrophoresis) presented that the number of significantly up-regulated spots (the Pep4p-deficient species versus the wild type) was 183, whereas the down-regulated spots numbered 111. Among them, 35 identified proteins were differentially down-regulated more than 10-fold in the Pep4p-deficient compared to the wild-type species. The data revealed that Pep4p was required for the synthesis and maturation of several glycolytic enzymes and stress proteins, including Eno2p, Fba1p, Pdc1p, Tpi1p, Ssa1, Hsp82p, and Trr1p. The transcription and post-translational modifications of glycolytic enzymes like Eno2p and Fba1p were sensitive to the absence of Pep4p; whereas the depletion of the pep4 gene had a negative impact on mitochondrial and other physiological functions. The finding of this study provides a systematic understanding that Pep4p may serve as a regulating factor for cell physiology and metabolic processes in S. cerevisiae under a nitrogen stress environment.

Myopia in human and animals is caused by the axial elongation of the eye and is closely linked to the thinning of the sclera which supports the eye tissue. This thinning has been correlated with the overproduction of matrix metalloproteinase (MMP-2), an enzyme that degrades the collagen structure of the sclera. In this short paper, we propose a descriptive model of a regulatory network with hysteresis, which seems necessary for creating oscillatory behavior in the hybrid model between MMP-2, MT1-MMP and TIMP-2. Numerical results provide insight on the type of equilibria present in the system.