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The house mouse is a common indoor pest found in the urban environment. Low-income communities often have the highest house mouse infestation rates due to inadequate pest management practices. We conducted an 18-month long study evaluating the effectiveness of three house mouse management strategies in a low-income community in New Jersey, U.S. Six buildings containing 156 apartments were divided into three groups, T&B, T&B+E, and control. The T&B treatment included the installment of traps and rodenticide baits. The T&B+E treatment included using traps and rodenticide baits, plus interior and exterior exclusion of the buildings. Researchers applied baits and traps inside apartments, crawl spaces, and basements and followed up until no mouse activity was found. Exclusion was completed by contracted vendors with oversight from researchers. The apartments in the control group were serviced by an existing contractor which used rodenticides and glue boards for mouse control and their treatment was offered only to residents who complained about mouse infestations. Building-wide inspections were conducted at 0, 6, 12, and 18 months to evaluate the effectiveness of the programs. T&B and T&B+E were more effective than the control in reducing house mouse infestations. The infestation rate in T&B, T&B+E, and control at 12 months (May 2023) was 2, 2, and 44%, respectively. The infestation rate rebounded in all groups from 12 to 18 months, which was probably related to lower temperatures in winter. T&B+E treatment caused faster reduction of mouse infestations than T&B treatment, but did not result in lower new infestations than T&B. The palatability of different rodenticides varied significantly. Kitchens had a higher amount of mouse activity than living rooms. A median number of three mice were caught by snap traps per infested apartment. Additional studies are suggested to determine the benefit of rodent exclusion.

This study investigated high-throughput screening of inhibitors for the key enzyme CitE in the synthesis of red yeast citrinin through computer simulation. First, Alphafold 2 was used to build the homology model of CitE. and it was aligned with similar sequences to predict the ligand binding region. Subsequently, a ligand library of 20 000 compounds was constructed by searching for natural ligands and flavonoid skeleton analogues in the Arthur database. Afterwards, molecular docking of the CitE protein to the library of small molecule compounds was performed using Maestro to select potential CitE ligands. Gromacs kinetic simulation was used to evaluate the binding stability, and the binding free energy was calculated using MM/PBSA. The protein-ligand binding mode was analyzed, confirming that six small molecule ligands including quercetin, luteolin, apigenin, genistein, 5,4’-dihydroxyflavone, and fisetin had strong CitE binding activities. The results from solid and liquid state fermentation showed that the above compounds exhibited significant inhibitory activity against Monascus citrinin production. Specifically, the addition of these compounds in solid state fermentation (20 mg/28 g of dry material) resulted in a reduction of Monascus citrinin production by 42.52%, 48.81%, 32.54%, 32.57%, 21.02%, and 13.67%, respectively, while their addition in liquid state fermentation (0.1 g/L) led to a reduction by 33.77%, 15.58%, 33.33%, 62.34%, 58.87%, and 50.22%, respectively. In summary, this study is of reference significance for establishing an efficient and safe Monasucs fermentation system.

In this study, the genomes of 19 Latilactobacillus curvatus and 40 L. sakei strains were comparatively analyzed. Average nucleic acid identity (ANI) and genome-wide colinearity indicated that the genomes of L. curvatus and L. sakei had weak nucleotide sequence homology, allowing them to be used as indicators to distinguish the two species. Pangenomes for these species were constructed, whose core gene functions were annotated. The results showed that the core genomes of L. curvatus and L. sakei were mainly involved in their basic metabolism. Analysis of individual genomes of the strains revealed that 1) both L. curvatus and L. sakei contained a wide range of genes encoding glycoside hydrolases, which are abundant genetic resources for catabolizing and metabolizing dietary fiber such as polysaccharides, lactose utilization, and lignocellulose; 2) antibiotic resistance genes were annotated in the genomes of three strains, which originate from horizontal gene transfer; 3) the unique arginine deiminase pathway of L. sakei, the serine dehydratase and guanine deaminase pathways of L. curvatus, and the glutamate decarboxylase pathway of several strains were identified, revealing that the acid tolerance mechanisms of these two species are different; and 4) genes encoding cold stress proteins were discovered, which endow the two species with good cold processing properties. Moreover, the genomes of some L. sakei strains contained gene clusters related to the biosynthesis of lactocin S and condensin. In conclusion, this study established taxonomic criteria for the two species and information on individual differences between their strains, which will provide a basis for the study of the physiological, biochemical, molecular genetic mechanisms of L. curvatus and L. sakei and their industrial applications.

Predicting cracking radius is a prerequisite for determining the holes spacing of gas extraction technology by liquid CO2 phase transition cracking and permeability improvement, which directly affects the gas extraction effect. Most existing prediction methods are based on single factor analysis. In order to grasp the influence of multiple factors on the radius of liquid CO2 phase transition cracking and effectively predict the spacing between holes, ANSYS/LS-DYNA numerical simulation software is used to carry out the research on predicting the radius of coal seam liquid CO2 phase transition cracking combing with orthogonal experiments. The numerical simulation results indicate that the order of factors affecting the radius of liquid CO2 phase transition cracking is ground stress>gas pressure>coal solidity coefficient. The cracking radius decreases with the increase of stress, and increases with the increase of gas pressure and coal solidity coefficient with a linear relationship. A multiple regression analysis is conducted on the numerical simulation results. A prediction model for the radius of liquid CO2 phase transition cracking is established based on three different coupling conditions of ground stress, gas pressure, and coal solidity coefficient. Industrial experiments are conducted on the coal mine site. Extraction boreholes are set up based on the predicted model calculation results. The pressure index method is used to test and analyze the gas extraction effect. The results show the following points. The gas pressure in the observation holes on both sides of the liquid CO2 phase transition cracking hole shows a decreasing trend with time. The farther away from the cracking hole in the initial stage of extraction, the greater the gas pressure. It is consistent with theoretical analysis and numerical simulation results. The effective cracking range of liquid CO2 phase transition is basically consistent with the predicted results. The gas volume fraction in the observation hole is 73.4% higher than that in the natural extraction hole, and the gas extraction efficiency is significantly improved.

Background and purpose: More and more patients with multiple primary early-stage lung cancer are choosing to receive stereotactic body radiation therapy (SBRT), and this study aimed to retrospectively analyze the efficacy and prognostic factors of SBRT. Methods: In this study, patients who underwent SBRT at Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine from August 2014 to December 2020 and who met the inclusion criteria were included. Patients with multiple primary early-stage lung cancer were examined for efficacy and prognostic factors. After using propensity score matching (PSM), the difference in efficacy of SBRT between single and multiple primary early-stage lung cancer was observed. Results: This study included 241 early-stage lung cancer patients with SBRT, including 94 patients with multiple primary early-stage lung cancer. The 3- and 5-year local control rate (LC), progression-free survival (PFS) and overall survival (OS) were 87.1% and 71.3%, 84.0% and 66.9%, 93.3% and 79.3% in multiple primary early-stage lung cancer, respectively. Patients with multiple primary early-stage lung cancer did not experience any grade 3 or higher pulmonary toxicity with an overall toxicity incidence of 54.3%, and grade 2 toxicity occurred in 24 patients (25.5%). There was a total of 18 (19.1%) recurrences, and there were 3 (3.2%), 1 (1.1%), 12 (12.7%) and 2 (2.1%) patients with multiple primary early-stage lung cancers who experienced local recurrence, regional recurrence, distant metastasis and uncertain death, respectively. Patients with multiple primary early-stage lung cancer and those with single primary early-stage lung cancer had significant differences in clinical features prior to PSM. After PSM, there were 56 patients with multiple primary early-stage lung cancer and 56 patients with single primary early-stage lung cancer, and there was no statistically significant difference in LC (P = 0.291), PFS (P = 0.954) and OS (P = 0.880). Age≥70 years was an independent risk factor for OS of multiple primary early-stage lung cancer, according to an analysis of the prognostic variables of SBRT in 94 patients with multiple primary early-stage lung cancer. Regarding synchronous (≤180 d) and metachronous (>180 d) multiple primary early-stage lung cancer, there was no discernible difference between the two groups (P = 0.440). There was no significant difference in the total number of treatments for multiple primary early-stage lung cancer (P = 0.232) and no significant difference in the type of treatment for multiple primary early-stage lung cancer (P = 0.225) among 59 patients with synchronous multiple primary early-stage lung cancer within 5 years of the first-to-last treatment interval. Conclusion: SBRT has a strong and comparable efficacy for multiple primary early-stage lung cancer compared with single primary early-stage lung cancer, making it a viable treatment choice. Based on age and tumor biological behavior of the lesion, future strategies and procedures for local intervention of multiple primary early-stage lung cancer need to be investigated.

Purpose: To compare the structure and antioxidant activity of arabinoxylan (AX) extracted from wheat bran of different varieties by different methods. Methods: AX was extracted from wheat bran from the cultivars ‘Bainong 207’, ‘Baihan 207’, ‘Guanmai 1’, ‘Huayu 198’ and ‘Huayu 166’ by alkali extraction, ultrasonic-assisted xylanase extraction or ultrasonic-assisted cellulase extraction, and its chemical composition, relative molecular mass, molecular structure, thermal stability and antioxidant activity were determined. Results: Among the three extraction methods, alkali extraction gave higher levels of AX yield and total sugar content, while enzymatic extraction retained polyphenols to a greater extent, which may contribute to the better antioxidant capacity of the AX-rich extract, but reduced the relative molecular mass of AX to a certain extent. The monosaccharide composition of enzymatically extracted AX was significantly different from that of alkali extracted AX, and the glycosidic linkage types in enzymatically extracted AX were more complex. Compared with ultrasonic-assisted cellulase extraction, higher AX yield and total sugar content were obtained using ultrasound-assisted xylanase, while the polyphenol content of AX obtained by ultrasound-assisted cellulase extraction was higher, and monosaccharide composition and glycosidic linkage types were also different between AXs extracted by the two enzymatic methods. In addition, the relative molecular mass, the monosaccharide composition, and the types and proportions of glycosidic linkage of AX extracted from wheat bran of different varieties were different. Conclusion: The structure and activity of AX extracted from wheat bran by alkali extraction, ultrasonic-assisted xylanase extraction and ultrasonic-assisted cellulase extraction were obviously different. Compared with alkali extraction, AX obtained by enzymatic extraction had lower yield and molecular mass, but higher polyphenol content and better antioxidant performance. Compared with ultrasound-assisted cellulase extraction, AX obtained by ultrasound-assisted xylanase extraction had higher yield and total sugar content, but lower polyphenol content. The structure of wheat bran AX varied with different extraction methods and varieties.

With the progress of technology, the high-speed gear transmission device, which is widely used in energy, petrochemical and other fields, develops towards the direction of high power, high line speed, high efficiency and lightweight. The herringbone gear is usually used in this kind of transmission device, and its dynamic particularity under high speed conditions has an important influence on the reliable operation of the equipment. Therefore, the model of herringbone gear transmission is established, the dynamic characteristics of various herringbone gear transmission are analyzed under the conditions of driving and load excitation, the dynamic simulation is carried out, and the product is tested. The results show that when the load is constant, the greater the angular speed of the gear, the greater the contact force on the gear and the higher the collision frequency. When the input speed increases from 500 r/min to 1 000 r/min and 1 488 r/min, the difference of velocity fluctuation amplitude is 2.27 rad/s, 4.76 rad/s and 9.37 rad/s respectively, and the maximum contact force is 1.87 times and 2.44 times of that under 500 r/min, respectively. The number of angular velocity fluctuation increases to 1.94 times and 2.94 times of the case of 500 r/min, respectively. When the load increases, the angular velocity fluctuation of driven gears decreases and the contact force increases. This study provides reference for the design of this kind of high speed transmission devices.

The flexspline features several modal characteristics that are related to its structural parameters, which could impose an impact on the stability and reliability of the system of harmonic gear transmission. In this article, we have integrated the method of orthogonal design with the approach of finite element, so as to study the modal characteristics of flexspline under varying structural parameters. Furthermore, we have analyzed the ways of how varying structural parameters could impose an impact on the first eight-order natural frequencies of flexspline. In addition, by adopting the method of range and variance analysis for the obtained data, we have examined the influence imposed by varying structural parameters on the modal characteristics of flexspline, which could lay a foundation for the optimal design of the structural parameters of flexspline.

BACKGROUND: The bites and blood sucking of bed bugs (Cimex spp.) (Hemiptera: Cimicidae) pose a serious threat to human physical and mental health. Application of an effective repellent can prevent or reduce bed bug bites. Previous studies on repellent screening mainly focused on Cimex lectularius L. In this study, we investigated the repellent effect of two safe food additives, ethyl anthranilate (EA) and butyl anthranilate (BA), against Cimex hemipterus (F.), and also explored the role of antennae and mouthparts on C. hemipterus perception of repellents. RESULTS: Both EA and BA had a strong repellent effect against tropical bed bugs and their repellency was similar or lower than that of N,N‐diethyl‐3‐methyl benzoyl amide, depending on whether or not a CO2 source was present. EA had higher repellency than BA and exhibited repellency to C. hemipterus for 3 days when a CO2 source was present. C. hemipterus avoided resting on 20% EA‐ and BA‐treated harborages. Applying 20% EA and BA on rabbit skin significantly reduced the blood intake of C. hemipterus within 2 h. C. hemipterus could perceive EA and BA after their antennae or mouthparts or both antennae and mouthparts were removed. CONCLUSION: Both EA and BA had strong repellency against C. hemipterus, with EA being more repellent. Ablation of antennae and mouthparts did not affect the perception of EA and BA by C. hemipterus. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Precision speed reducer is one of the key parts of industrial robot. For a long time,its Core Technology has been monopolized by the several foreign developed countries,which seriously restricting the development of China robot industry.Technology development and its status of RV reducer at home and abroad were described in paper. Then,the main causes of restricting the development of our countries’ RV reducer have been detailed analyzed. Relevant documents and policies were sketched,which play an active role in promoting the RV reducer. Finally,some personal opinions and suggestions on how to improve the situation of our countries’ precision speed reducer were submitted.

With the development of industry,harmonic gear drive technology has been more and more applied with its special advantages. The principle,characteristics and application of harmonic gear drive are briefly introduced,the domestic and foreign development situation of it is briefly summarized,a detailed analysis of the research focus and development trend,and general discussion are carried out.

The model of rotor vector (RV) reducer was established by 3D software, and was imported into ANSYS Workbench for transient dynamic analysis. The stress distribution diagram and total deformation diagram of the gear tooth surface during the meshing process of the cycloidal wheel and the pin wheel were obtained, and the stress distribution law of the cycloidal wheel in the process was also obtained. Comparing the calculation results of Hertz formula with the results of finite-element analysis showed that the deviation are smaller and within the allowable range, which provides the theoretical reference for the optimisation of the cycloidal wheel.