THREE STUDIES OF 2-PYRIDONE PHOTOADDUCT REACTIVITY

2-Pyridones such as iii undergo efficient [4+4] photocycloaddition reactions, yielding strained tricyclic cyclooctadiene structures iv and v, with functionality at every carbon. As part of a program to develop the chemistry of these complex adducts, three studies have been conducted. Halogenation of trans iv give rearranged i. Cope rearrangement of cis v gives vi which can undergo retro-Mannich reaction to yield unsymmtrically coupled piperidines vii. Pyridones can also undergo photo-[4+4] reactions with furans. Cycloaddition of viii yields ix. Transannular closure of ix produces triquinane x, a model system for total synthesis of crinipellin A xi.Chemistr

Stability of linear lossless propagation systems Exact conditions via matrix pencil solutions

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Trends in incidence and mortality of colorectal cancer and related life loss in Haishu District， Ningbo of Zhejiang Province， 2017‒2022

ObjectiveTo analyze the trend of incidence, mortality rate and related life loss of colorectal cancer in Haishu District, Ningbo from 2017 to 2022, so as to provide a scientific basis for the prevention and treatment of colorectal cancer.MethodsThe incidence and death data of colorectal cancer among residents in Haishu District during 2017‒2022 were collected from the Ningbo Municipal Digital Disease Prevention and Control Platform. The incidence and mortality rate, the age-specific incidence and mortality rate, potential years of life lost (PYLL), potential years of life lost rate (PYLLR), and average years of life lost (AYLL) were calculated. The standardized rate was calculated based on the standardized population from the Sixth National Census in 2010, and the annual percentage change (APC) was calculated by Joinpoint Regression Program.ResultsA total of 2 595 cases of colorectal cancer were reported in Haishu District from 2017 to 2022, with a crude incidence rate of 68.23/100 000 and a standardized incidence rate of 39.72/100 000. There were no statistical differences in crude and standardized incidence rates(APC=2.288%, -0.160%,both P>0.05). In addition, a total of 898 colorectal cancer deaths were reported, with a crude mortality rate of 23.61/100 000 and a standardized mortality rate of 12.18/100 000, of which the crude mortality rate and standardized mortality rate of males showed an upward trend (APC=10.855%, 7.895%, both P<0.05). Furthermore, the crude incidence and mortality rate of colorectal cancer in males were higher than those in females (both P<0.05). The crude incidence and mortality rate of colorectal cancer in Haishu District showed an increasing trend by age (both P<0.05). PYLL caused by colorectal cancer was 7 818.52 person-years, and AYLL was 8.71 years, with a PYLLR of 2.06‰.ConclusionThe incidence and mortality rate of colorectal cancer in Haishu District are still at a high level. Colorectal cancer screening should be continued, relevant health knowledge should be facilitated and disseminated, awareness of early screening and diagnosis of colorectal cancer should be promoted, and ultimately improving the survival rate of the patients

Arecoline induces dual modulation of blood pressure in rat, including an initial downregulation and a subsequent upregulation

Purpose: To determine the role of arecoline in cardiovascular modulation in rats.Methods: After rats were anaesthetized with intraperitoneal urethane (1.4 g/kg body weight), saline or arecoline (at doses of 1.0, 3.0 and 10.0 mg/kg) was intraperitoneally administered, and blood pressure (BP) was continuously recorded using a physiological apparatus. Mean arterial pressure (MAP), maximum changes in MAP and reaction time due to arecoline stimulations were calculated and analyzed.Results: Arecoline induced biphasic modulation in BP, including an initial downregulation followed by a subsequent upregulation. The MAP and maximum change in MAP exhibited a concentration-dependent effect in the downregulation phase (p &lt; 0.001 within each group), but not in the upregulation phase (p &gt; 0.05 within each group), while BP reaction time showed a dose-dependent prolongation in both downregulation and upregulation phases (ps &lt; 0.01 within each group). Remarkably, arecoline-induced BP downregulation more rapidly and drastically than upregulation in each arecoline group.Conclusion: These results indicate that arecoline exerts a complex effect in cardiovascular modulation that should be considered as side effects in the clinical use of arecoline and/or with the habitual chewing of areca nuts. Keywords: Arecoline, Blood pressure, Downregulation, Upregulatio

Comprehensive analysis of mitogen-activated protein kinase cascades in chrysanthemum

Background Mitogen-activated protein kinase (MAPK) cascades, an important type of pathway in eukaryotic signaling networks, play a key role in plant defense responses, growth and development. Methods Phylogenetic analysis and conserved motif analysis of the MKK and MPK families in Arabidopsis thaliana, Helianthus annuus and Chrysanthemum morifolium classified MKK genes and MPK genes. qRT-PCR was used for the expression patterns of CmMPK and CmMKK genes, and yeast two-hybrid assay was applied to clear the interaction between CmMPKs and CmMKKs. Results We characterized six MKK genes and 11 MPK genes in chrysanthemum based on transcriptomic sequences and classified these genes into four groups. qRT-PCR analysis demonstrated that CmMKKs and CmMPKs exhibited various expression patterns in different organs of chrysanthemum and in response to abiotic stresses and phytohormone treatments. Furthermore, a yeast two-hybrid assay was applied to analyze the interaction between CmMKKs and CmMPKs and reveal the MAPK cascades in chrysanthemum. Discussion Our data led us to propose that CmMKK4-CmMPK13 and CmMKK2-CmMPK4 may be involved in regulating salt resistance and in the relationship between CmMKK9 and CmMPK6 and temperature stress

Soil-transmitted helminth infections and physical fitness in school-aged Bulang children in southwest China: results from a cross-sectional survey

BACKGROUND: Chronic soil-transmitted helminth (STH) infections have been associated with reduced physical fitness, but available evidence is limited. The aim of this cross-sectional survey was to assess the feasibility of measuring children's physical fitness and to relate it to STH infections. Our study was carried out among school-aged children of the Bulang ethnic group in rural southwest People's Republic of China (P.R. China). Standardized, quality-controlled methods were employed to determine STH infections (Kato-Katz technique), haemoglobin levels, anthropometry (body weight and height) and physical fitness (20-m shuttle run test). RESULTS: A compliance of 87% suggested good acceptance of the methods used. Among 69 children with complete data records, infection prevalence of Trichuris trichiura, Ascaris lumbricoides and hookworm were 81%, 44% and 6%, respectively. The maximum volume of oxygen that can be utilized within 1 min during exhaustive exercise (VO2 max estimate) of T. trichiura-infected children was 1.94 ml kg1 min1 lower than that of their non-infected counterparts (P = 0.005). Until exhaustion, T. trichiura-infected children had completed 6.14 20-m laps less (P = 0.004). Additionally, the mean VO2 max estimate of stunted children was lowered by 1.63 ml kg1 min1 (P = 0.002) and they completed 5.32 20-m laps less (P = 0.001) compared to children of normal stature. No significant association between stunting and infection with any STH species could be established. CONCLUSIONS: Implementation of physical fitness tests in rural, resource-constraint settings is feasible. The physical fitness of children who are stunted or infected with STHs, particularly T. trichiura, is significantly impaired. We have launched a larger study and will determine the dynamics of school-aged children's physical fitness over a 7-month period after administration of anthelminthic drugs

Deep-STP: a deep learning-based approach to predict snake toxin proteins by using word embeddings

Snake venom contains many toxic proteins that can destroy the circulatory system or nervous system of prey. Studies have found that these snake venom proteins have the potential to treat cardiovascular and nervous system diseases. Therefore, the study of snake venom protein is conducive to the development of related drugs. The research technologies based on traditional biochemistry can accurately identify these proteins, but the experimental cost is high and the time is long. Artificial intelligence technology provides a new means and strategy for large-scale screening of snake venom proteins from the perspective of computing. In this paper, we developed a sequence-based computational method to recognize snake toxin proteins. Specially, we utilized three different feature descriptors, namely g-gap, natural vector and word 2 vector, to encode snake toxin protein sequences. The analysis of variance (ANOVA), gradient-boost decision tree algorithm (GBDT) combined with incremental feature selection (IFS) were used to optimize the features, and then the optimized features were input into the deep learning model for model training. The results show that our model can achieve a prediction performance with an accuracy of 82.00% in 10-fold cross-validation. The model is further verified on independent data, and the accuracy rate reaches to 81.14%, which demonstrated that our model has excellent prediction performance and robustness

AITP-YOLO: improved tomato ripeness detection model based on multiple strategies

IntroductionThis paper offers a multi-scale AITP-YOLO model, based on the enhanced YOLOv10s model, to address the challenges of difficult identification and frequent misdetection of tomatoes, facilitating ripeness detection under realistic conditions.MethodsA four-head detector incorporates a small target detection layer, enhancing the model's capacity to identify small targets. Secondly, a multi-scale feature fusion technique employing cross-level features is implemented in the feature fusion layer to amalgamate convolutions of varying sizes, enhancing the model's fusion capacity and generalization proficiency for features of diverse scales. The bounding box loss function is modified to Shape-IoU, with the loss computed by emphasizing the shape and scale of the bounding box, hence enhancing the precision of bounding box regression, expediting model convergence, and augmenting model correctness. Ultimately, the model is compressed via Network Slimming puring,which removes redundant channels while mataining detection accuracy.ResultsThe experimental findings indicate that the enhanced model achieves average precision, accuracy, and recall of 92.6%, 89.7%, and 87.4%, respectively. In comparison to the baseline network YOLOv10s, the model weights are compressed by 7.64%, while average precision, accuracy, and recall are elevated by 4.6%, 5.8%, and 7.3%, respectively.DiscussionThe enhanced model features a reduced model size while exhibiting superior detection capabilities, enabling more efficient and precise recognition of tomato stages amidst complicated backgrounds, hence offering a valuable technical reference for automated tomato harvesting technology

The FilZ protein contains a single PilZ domain and facilitates the swarming motility of pseudoalteromonas sp. SM9913

Swarming regulation is complicated in flagellated bacteria, especially those possessing dual flagellar systems. It remains unclear whether and how the movement of the constitutive polar flagellum is regulated during swarming motility of these bacteria. Here, we report the downregulation of polar flagellar motility by the c-di-GMP effector FilZ in the marine sedimentary bacterium Pseudoalteromonas sp. SM9913. Strain SM9913 possesses two flagellar systems, and filZ is located in the lateral flagellar gene cluster. The function of FilZ is negatively controlled by intracellular c-di-GMP. Swarming in strain SM9913 consists of three periods. Deletion and overexpression of filZ revealed that, during the period when strain SM9913 expands quickly, FilZ facilitates swarming. In vitro pull-down and bacterial two-hybrid assays suggested that, in the absence of c-di-GMP, FilZ interacts with the CheW homolog A2230, which may be involved in the chemotactic signal transduction pathway to the polar flagellar motor protein FliMp, to interfere with polar flagellar motility. When bound to c-di-GMP, FilZ loses its ability to interact with A2230. Bioinformatic investigation indicated that filZ-like genes are present in many bacteria with dual flagellar systems. Our findings demonstrate a novel mode of regulation of bacterial swarming motility