Optimizing Nav1.7-Targeted Analgesics: Revealing Off-Target Effects of Spider Venom-Derived Peptide Toxins and Engineering Strategies for Improvement.

The inhibition of Nav1.7 is a promising strategy for the development of analgesic treatments. Spider venom-derived peptide toxins are recognized as significant sources of Nav1.7 inhibitors. However, their development has been impeded by limited selectivity. In this study, eight peptide toxins from three distinct spider venom Nav channel families demonstrated robust inhibition of hNav1.7, rKv4.2, and rKv4.3 (rKv4.2/4.3) currents, exhibiting a similar mode of action. The analysis of structure and function relationship revealed a significant overlap in the pharmacophore responsible for inhibiting hNav1.7 and rKv4.2 by HNTX-III, although Lys25 seems to play a more pivotal role in the inhibition of rKv4.2/4.3. Pharmacophore-guided rational design is employed for the development of an mGpTx1 analogue, mGpTx1-SA, which retains its inhibition of hNav1.7 while significantly reducing its inhibition of rKv4.2/4.3 and eliminating cardiotoxicity. Moreover, mGpTx1-SA demonstrates potent analgesic effects in both inflammatory and neuropathic pain models, accompanied by an improved in vivo safety profile. The results suggest that off-target inhibition of rKv4.2/4.3 by specific spider peptide toxins targeting hNav1.7 may arise from a conserved binding motif. This insight promises to facilitate the design of hNav1.7-specific analgesics, aimed at minimizing rKv4.2/4.3 inhibition and associated toxicity, thereby enhancing their suitability for therapeutic applications.

Machine learning models for daily net radiation prediction across different climatic zones of China.

Net radiation (Rn), a critical component in land surface energy cycling, is calculated as the difference between net shortwave radiation and longwave radiation at the Earth's surface and holds significant importance in crop models for precision agriculture management. In this study, we examined the performance of four machine learning models, including extreme learning machine (ELM), hybrid artificial neural networks with genetic algorithm models (GANN), generalized regression neural networks (GRNN), and random forests (RF), in estimating daily Rn at four representative sites across different climatic zones of China. The input variables included common meteorological factors such as minimum and maximum temperature, relative humidity, sunshine duration, and shortwave solar radiation. Model performance was assessed and compared using statistical parameters such as the correlation coefficient (R2), root mean square errors (RMSE), mean absolute errors (MAE), and Nash-Sutcliffe coefficient (NS). The results indicated that all models slightly underestimated actual Rn, with linear regression slopes ranging from 0.810 to 0.870 across different zones. The estimated Rn was found to be comparable to observed values in terms of data distribution characteristics. Among the models, the ELM and GANN demonstrated higher consistency with observed values, exhibiting R2 values ranging from 0.838 to 0.963 and 0.836 to 0.963, respectively, across varying climatic zones. These values surpassed those of the RF (0.809-0.959) and GRNN (0.812-0.949) models. Additionally, the ELM and GANN models showed smaller simulation errors in terms of RMSE, MAE, and NS across the four climatic zones compared to the RF and GRNN models. Overall, the ELM and GANN models outperformed the RF and GRNN models. Notably, the ELM model's faster computational speed makes it a strong recommendation for Rn estimates across different climatic zones of China.

Dietary Rhythmicity and Mental Health Among Airline Personnel.

Importance: Misaligned dietary rhythmicity has been associated with metabolic diseases; however, its association with mental health remains largely unexplored. Objective: To examine the association between dietary rhythms and the mental health condition of shift workers, specifically airline crew members. Design, Setting, and Participants: This cross-sectional study analyzed data collected from the Civil Aviation Health Cohort of China, an ongoing large-scale health survey of pilots, flight attendants, and air security officers employed by major airline companies in China. Participants aged 18 to 60 years were invited through text messages to complete a web-based survey. The data collection period was December 2022 to March 2023. Statistical analysis was performed from July 24, 2023, to April 12, 2024. Exposure: Data on timing of breakfast and dinner on workdays and rest days, daily time windows for food intake, and meal and eating jet lags were collected and calculated. Main Outcomes and Measures: Anxiety and depressive symptoms were measured using the 7-item Generalized Anxiety Disorder Assessment and the 9-item Patient Health Questionnaire. Multivariate logistic regressions were performed to evaluate the associations of anxiety and depression with meal timing, eating window time, meal jet lag (ie, delayed meals), and eating jet lag (ie, delayed eating). All models were adjusted for individual socioeconomic, demographic, and lifestyle characteristics. Results: Of the 22 617 participants (median [IQR] age, 29.1 [26.3-33.7] years; 13 712 males [60.6%]), 1755 (7.8%) had anxiety and 2768 (12.2%) had depression. After controlling for confounding factors, having dinner after 8 pm on morning-shift days was associated with increased odds of anxiety (adjusted odds ratio [AOR], 1.78; 95% CI, 1.53-2.05) and depression (AOR, 2.01; 95% CI, 1.78-2.27), compared with consuming dinner before 8 pm. Similar results were observed on night-shift days and rest days. An eating window of less than 12 hours was associated with reduced odds of anxiety (AOR, 0.84; 95% CI, 0.75-0.93) and depression (AOR, 0.81; 95% CI, 0.75-0.89) on morning-shift days; the results remained significant on rest days. Delayed dinner on morning-shift days was associated with increased odds of anxiety (AOR, 1.32; 95% CI, 1.13-1.54) and depression (AOR, 1.39; 95% CI, 1.22-1.58). On night-shift days, delayed dinner was associated with higher odds of anxiety (AOR, 1.22; 95% CI, 1.06-1.39) and depression (AOR, 1.21; 95% CI, 1.08-1.36). On morning-shift days, delayed eating rhythms were associated with higher odds of depression (AOR, 1.35; 95% CI, 1.13-1.61), whereas advanced eating rhythms were associated with lower odds of anxiety (AOR, 0.78; 95% CI, 0.70-0.87). Conclusions and Relevance: This cross-sectional study found that meal timing, long eating window, and meal jet lags were associated with increased odds of depression and anxiety. These findings underscore the need for interventions and supportive policies that help mitigate the adverse implications of shift work and irregular working hours for the mental health of shift workers.

Directly Converting Bulk Wood into Branch Micro-Nano Fibers to Synergistically Enhance the Strength and Toughness via Interface Engineering.

Hierarchical biobased micro/nanomaterials offer great potential as the next-generation building blocks for robust films or macroscopic fibers with high strength, while their capability in suppressing crack propagation when subject to damage is hindered by their limited length. Herein, we employed an approach to directly convert bulk wood into fibers with a high aspect ratio and nanosized branching structures. Particularly, the length of microfibers surpassed 1 mm with that of the nanosized branches reaching up to 300 µm. The presence of both interwoven micro- and nanofibers endowed the product with substantially improved tensile strength (393.99 MPa) and toughness (19.07 MJ m-3). The unique mechanical properties arose from mutual filling and the hierarchical deformation facilitated by branched nanofibers, which collectively contributed to effective energy dissipation. Hence, the nanotransformation strategy opens the door toward a facial, scalable method for building high-strength film or macroscopic fibers available in various advanced applications.

Prevalence and network analysis of internet addiction, depression and their associations with sleep quality among commercial airline pilots: A national survey in China.

OBJECTIVE: Airline pilots are members of a unique occupational group that is often confronted with sleep routine disruptions, yet relatively few studies have examined their mental health status. This study assessed the prevalence and network structure of internet addiction, depression and sleep quality problems in commercial airline pilots. METHOD: A total of 7055 airline pilots were included in analyses. Internet addiction and depression were measured with the Internet Addiction Test (IAT) and 9-item Patient Health Questionnaire (PHQ-9), respectively. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). The network model was constructed based on an Ising model and its association with sleep quality was evaluated using a flow procedure. RESULTS: Internet addiction, depression and sleep quality were common among airline pilots. The prevalence of internet addiction was 8.0 % (95 % CI: 7.3-8.6 %), while the rates of depression and poor sleep quality were 23.3 % (95 % CI: 22.3-24.2 %) and 33.0 % (95 % CI: 31.9-34.1 %), respectively. In the depression and internet addiction network model, "Fatigue" (PHQ4; Expected Influence (EI): 2.04) and "Depressed/moody/nervous only while being offline" (IAT20; EI: 1.76) were most central symptoms while "Fatigue" (PHQ4; Bridge EI: 1.30) was also the most important bridge symptom. The flow network model of sleep quality with internet addiction and depression showed that "Appetite" (PHQ5) had the strongest positive association with poor sleep quality. CONCLUSION: Internet addiction, depression and sleep quality were common among airline pilots and warrant regular screening and timely treatment. Strategies to improve sleep hygiene may be useful in preventing onsets or exacerbations in depression and internet addiction among airline pilots.

Ultrastable halide perovskite CsPbBr3 photoanodes achieved with electrocatalytic glassy-carbon and boron-doped diamond sheets.

Halide perovskites exhibit exceptional optoelectronic properties for photoelectrochemical production of solar fuels and chemicals but their instability in aqueous electrolytes hampers their application. Here we present ultrastable perovskite CsPbBr3-based photoanodes achieved with both multifunctional glassy carbon and boron-doped diamond sheets coated with Ni nanopyramids and NiFeOOH. These perovskite photoanodes achieve record operational stability in aqueous electrolytes, preserving 95% of their initial photocurrent density for 168 h of continuous operation with the glassy carbon sheets and 97% for 210 h with the boron-doped diamond sheets, due to the excellent mechanical and chemical stability of glassy carbon, boron-doped diamond, and nickel metal. Moreover, these photoanodes reach a low water-oxidation onset potential close to +0.4 VRHE and photocurrent densities close to 8 mA cm-2 at 1.23 VRHE, owing to the high conductivity of glassy carbon and boron-doped diamond and the catalytic activity of NiFeOOH. The applied catalytic, protective sheets employ only earth-abundant elements and straightforward fabrication methods, engineering a solution for the success of halide perovskites in stable photoelectrochemical cells.

Comparison of biliary protein spectrum in gallstone patients with obesity and those with normal body weight.

BACKGROUND: Obesity is a common public health issue and is currently deemed a disease. Research has shown that the risk of gallstones in individuals with obesity is elevated. This study aimed to explore the bile proteomics differences between cholelithiasis patients with obesity and normal body weight. METHODS: Bile samples from 20 patients (10 with obesity and 10 with normal body weight) who underwent laparoscopic cholecystectomy at our center were subjected to tandem mass tag labeling (TMT) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), followed by further bioinformatic analysis. RESULTS: Among the differentially-expressed proteins, 23 were upregulated and 67 were downregulated. Bioinformatic analysis indicated that these differentially-expressed proteins were mainly involved in cell development, inflammatory responses, glycerolipid metabolic processes, and protein activation cascades. In addition, the activity of the peroxisome proliferator-activated receptor (PPAR, a subfamily of nuclear receptors) signaling pathway was decreased in the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Two downregulated proteins in the PPAR signaling pathway, APOA-I and APOA-II, were confirmed using enzyme-linked immunosorbent assay. CONCLUSIONS: The PPAR signaling pathway may play a crucial role in the development of cholelithiasis among patients with obesity. Furthermore, biliary proteomics profiling of gallstones patients with obesity is revealed, providing a reference for future research.

LmNaTx15, a novel scorpion toxin, enhances the activity of Nav channels and induces pain in mice.

Polypeptide toxins are major bioactive components found in venomous animals. Many polypeptide toxins can specifically act on targets, such as ion channels and voltage-gated sodium (Nav) channels, in the nervous, muscle, and cardiovascular systems of the recipient to increase defense and predation efficiency. In this study, a novel polypeptide toxin, LmNaTx15, was isolated from the venom of the scorpion Lychas mucronatus, and its activity was analyzed. LmNaTx15 slowed the fast inactivation of Nav1.2, Nav1.3, Nav1.4, Nav1.5, and Nav1.7 and inhibited the peak current of Nav1.5, but it did not affect Nav1.8. In addition, LmNaTx15 altered the voltage-dependent activation and inactivation of these Nav channel subtypes. Furthermore, like site 3 neurotoxins, LmNaTx15 induced pain in mice. These results show a novel scorpion toxin with a modulatory effect on specific Nav channel subtypes and pain induction in mice. Therefore, LmNaTx15 may be a key bioactive component for scorpion defense and predation. Besides, this study provides a basis for analyzing structure-function relationships of the scorpion toxins affecting Nav channel activity.

Shape and Stiffness Switchable Hydroplastic Wood with Programmability and Reproducibility.

Stiffness switchable materials (e.g., supramolecular polymers, metals) that alter their shape and mechanical properties in response to specific stimuli are potentially utilized in the structural engineering field but still limited due to the use of petroleum-based synthetic monomers and large energy consumption. Herein, a sustainable and facile solvent casting strategy is proposed to fabricate the "hydroplastic wood" with shape and stiffness switchable properties via cell wall wetting, cell wall softening and subsequent moisture evaporation. Therein, a wetting agent with low surface tension and low viscosity is utilized for covering the rough surface of solid wood to form a liquid lubricating layer, thereby increasing the interfacial wettability and achieving uniform softening of the cell walls. This interface wetting treatment can easily break through the hydro-plasticization process for thick wood (Balsa wood, Ochroma lagopus Swartz, density: 0.25 g/cm3; Pinewood, Pinus armandii, density: 0.38 g/cm3). Additionally, the capillary force arising from moisture evaporation induces the self-densification of oriented cellulose nanofibrils and achieves moisture-mediated shape design capabilities through periodic saturation-dehydration. This work makes hydroplastic wood a promising candidate for engineering materials because of its combined advantages of strong durability, formability, and load-carrying capacity.

Low-temperature strain-sensitive sensor based on cellulose-based ionic conductive hydrogels with moldable and self-healing properties.

Bioelectronics based on high-performance conductive ionic hydrogels, which can create novel technological interfaces with the human body, have attracted significant interest from both academia and industry. However, it is still a challenge to fabricate hydrogel sensor with integration of good mechanical properties, fast self-healing ability and flexible strain sensitivity below 0 °C. In this paper, we present a moldable, self-healing and adhesive cellulose-based ionic conductive hydrogel with strain-sensitivity, which was prepared by forming dual-crosslinked networks using poly(vinyl alcohol) (PVA) with borax, calcium chloride (CaCl2), zinc chloride (ZnCl2) and 2,2,6,6-tetramethylpiperidine-1-oxyl oxidized cellulose nanofibril (TCNF). The hydrogel exhibited fast self-healing within 10 s, moderate modulus of 5.13 kPa, high elongation rate of 1500 % and excellent adhesion behavior on various substrates. Due to multiple hydrogen bonding and the presence of CaCl2 and ZnCl2, the hydrogel presented a reduced freezing point as low as -41.1 °C, which enabled its application as a low-temperature strain sensor. The proposed hydrogel provides a simple and facile method for fabricating multi-functional hydrogels that can be used as suitable strain sensors for applications such as wearable electronic sensor, soft robotics and electronic skins in a wide temperature range.

Transcriptome analysis reveals the peptide toxins diversity of Macrothele palpator venom.

Spider venom is a large pharmacological repertoire of different bioactive peptide toxins. However, obtaining crude venom from some spiders is challenging. Thus, studying individual toxins through venom purification is a daunting task. In this study, we constructed the cDNA library and transcriptomic sequencing from the Macrothele palpator venom glands. Subsequently, 718 high-quality expressed sequence tags (ESTs) were identified, and grouped into three categories, including 449 toxin-like (62.53 %), 136 cellular component (18.94 %) and 133 non-matched (18.52 %) based on the gene function annotation. Additionally, 112 non-redundant toxin-like peptides were classified into 13 families (families A-M) based on their sequence homology and cysteine framework. Bioinformatics analysis revealed a high sequence similarity between families A-J and the toxins from Macrothele gigas in the NR database. In contrast, families K-M had a generally low sequence homology with known spider peptide toxins and unpredictable biological functions. Taken together, this study adds many new members to the spider toxin superfamily and provides a basis for identifying various potential biological tools in M. palpator venom.

Switch/Sucrose Non-Fermentable Complex-Deficient Rhabdoid Carcinoma of Stomach: A Rare Case Report and Literature Review.

Gastric undifferentiated/rhabdoid carcinoma is a rare highly invasive tumor of epithelial origin. Due to mutations in the switch/sucrose non-fermentable (SWI/SNF) complex, these tumor cells are usually dedifferentiated, presenting a characteristic rhabdoid profile. In this report, we present a gastric rhabdoid carcinoma in a 77-year-old man who presented with intermittent epigastric pain. Gastroscopy revealed a giant ulcer in the antrum, which proved to be a malignant tumor in the biopsy. Therefore, he was admitted to our hospital and underwent laparoscopic radical gastrectomy and D2 lymphadenectomy. The resected neoplasm contained a variety of rhabdoid cells that lacked well-differentiated elements. Immunohistochemical staining revealed that SMARCA4/BRG1 expression was absent in tumor cells. Finally, the patient was diagnosed with undifferentiated/rhabdoid carcinoma of the stomach. The patient was treated with tegafur-gimeracil-oteracil potassium capsules postoperatively. There were no signs of imaging changes observed at the 18-month follow-up. We reviewed similar cases in previous reports. These tumors are more likely to affect older male adults and usually lack typical symptoms. Histologically, most tumor cells are poorly cohesive and rhabdoid, and differentiated compositions of various degrees can occasionally be seen. Positive staining for vimentin was seen in all tumor cells. Epithelial markers are positive in the majority of tumors. SWI/SNF mutant tumors tend to be associated with a poor prognosis. In this review, more than half of the patients died within one year after surgery. The treatments for these diseases are still being explored.

Predictive value of NLR and PLR in missed miscarriage.

BACKGROUND: The aim of the study was to investigate the predictive value of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) in missed miscarriage. METHODS: In this retrospective cohort study, a total of 400 women (involving 200 with missed early miscarriage and 200 with normal pregnancy but terminate by artificial abortion) were included. General clinical data and complete blood count (CBC) such as white blood cells (WBC), red blood cells (RBC), platelet (PLT), red blood cell distribution width-standard deviation (RDW-SD), platelet distribution width (PDW), mean platelet volume (MPV), neutrophil count, and lymphocyte count were collected, and the NLR and PLR were calculated for both groups. Receiver operating characteristic curve (ROC) was used to calculate the predictive value. RESULTS: There was no significant difference in the WBC, RBC, PLT, RDW-SD, PDW, neutrophil, lymphocyte, NLR, and PLR between the two groups (p > 0.05).But MPV was lower in the missed early miscarriage group than in the control group (p < 0.05), and the area under the working curve (AUC) of ROC was 0.58, specificity and sensitivity was 69% and 47%, respectively. CONCLUSION: NLR and PLR were not the suitable indictor for missed miscarriage, but MPV should be a concern in the first trimester.

Synthesis of carbon dots with high photocatalytic reactivity by tailoring heteroatom doping.

The photocatalytic degradation of organic pollutant by carbon-based materials is still a challenge. Herein, xylose-derived carbon dots (X-CDs) and chitosan-derived CDs (C-CDs) were synthesized by heteroatoms-doping strategy. Although there is almost no difference in fluorescence emission behaviors, the two types of CDs demonstrated different advantages in photocatalysis and peroxymonosulfate (PMS) activation. Comparative research revealed that the X-CDs with doping of heteroatom S was superior in the separation of electron-hole pairs, resulting in a higher catalytic performance, while the S, N co-doped C-CDs can only exhibit high photocatalytic reactivity when they were coupled with PMS. The underlying reason is that the N-related functional groups with strong electron-donating property weakened the electron-trapping capacity of S-related energy level, but surface state resulting from this doping structures were conducive to promoting photo-generated electron transfer from C-CDs to PMS and played the primary role in organic oxidation. Thanks to the doping effect, both the X-CDs and C-CDs/PMS system displayed high photocatalytic performance for methylene blue removal under sunlight irradiation, showing almost 100% degradation efficiency in a 30 min period. The present study provides a valuable insight for the synthesis of CDs-based catalysts but also establishes a very promising catalytic oxidation system.

A Novel Spider Toxin Inhibits Fast Inactivation of the Nav1.9 Channel by Binding to Domain III and Domain IV Voltage Sensors.

Venomous animals have evolved to produce peptide toxins that modulate the activity of voltage-gated sodium (Nav) channels. These specific modulators are powerful probes for investigating the structural and functional features of Nav channels. Here, we report the isolation and characterization of δ-theraphotoxin-Gr4b (Gr4b), a novel peptide toxin from the venom of the spider Grammostola rosea. Gr4b contains 37-amino acid residues with six cysteines forming three disulfide bonds. Patch-clamp analysis confirmed that Gr4b markedly slows the fast inactivation of Nav1.9 and inhibits the currents of Nav1.4 and Nav1.7, but does not affect Nav1.8. It was also found that Gr4b significantly shifts the steady-state activation and inactivation curves of Nav1.9 to the depolarization direction and increases the window current, which is consistent with the change in the ramp current. Furthermore, analysis of Nav1.9/Nav1.8 chimeric channels revealed that Gr4b preferentially binds to the voltage-sensor of domain III (DIII VSD) and has additional interactions with the DIV VSD. The site-directed mutagenesis analysis indicated that N1139 and L1143 in DIII S3-S4 linker participate in toxin binding. In sum, this study reports a novel spider peptide toxin that may slow the fast inactivation of Nav1.9 by binding to the new neurotoxin receptor site-DIII VSD. Taken together, these findings provide insight into the functional role of the Nav channel DIII VSD in fast inactivation and activation.

Expression of Tspan8 in Patients with Intrahepatic Cholangiocarcinoma and Its Relationship with Clinicopathological Features and Prognosis.

The incidence and mortality of intrahepatic cholangiocarcinoma (ICC) are increasing worldwide. High invasion and metastasis are one of the main causes of death in patients. The selection of reasonable and effective molecular markers to evaluate the prognosis of patients with ICC has important clinical guiding significance. In this study, the expression of Tspan protein in ICC and normal tissues was compared, the correlation between Tspan expression and pathological features of patients was analyzed by the logistic regression model using multivariate analysis, and the relationship between Tspan8 expression and prognosis of ICC patients was analyzed by the Kaplan-Meier survival curve. The results showed that Tspan8 is highly positive in ICC tissues, TNM stage, degree of tumor differentiation, lymph node metastasis, and Tspan8 protein expression were independently correlated, and the overexpression of Tspan was associated with the prognosis of ICC invasion and metastasis. This provides a new idea for clinical treatment.

Cellulose nanocrystals concentration and oil-water ratio for solid-liquid controllable emulsion polymerization.

Stabilities of cellulose Pickering emulsions are of great importance to utilize them effectively, but influenced by their complex compositions, such as, colloidal particles, oil phases and water phases. In this work, solid-liquid controllable polymerization products could obtain by adjusting cellulose nanocrystals (CNCs) concentration and vinyl acetate (VAc)-water ratio. The emulsions in zone Ӏ (w/o) and II (o/w) of the three-phase diagram were selected for researching. The polymerization emulsions in zone II illustrated the o/w ratio played a more important role than CNCs concentration in the storage stability and practicality of the polymerized emulsion; The polymer in zone Ӏ showed a large number of porous structures. This is an innovative method that different forms of target products are obtained through the guidance of three-phase diagram, which not only broadens the application field, but also applies to other Pickering emulsion systems.

Boll-leaf system gas exchange and its application in the analysis of cotton photosynthetic function.

Estimating the boll development and boll yield from single-leaf photosynthesis is difficult as the source-sink relationship of cotton (Gossypium hirsutum L.) is complicated. As the boll-leaf system (BLS), which includes the main-stem leaf, sympodial leaf, and non-leaf organs, is the basic unit of the cotton source-sink relationship and yield formation, the concept of "BLS photosynthesis" is introduced in this study. We speculate that the characteristics of BLS gas exchange can more accurately reflect the photosynthetic function of the system, thus revealing the law of photosynthesis in the process of boll development. The results showed that the photosynthetic rate of single leaves measured by a BLS chamber was consistent with that measured by a standard single-leaf chamber. BLSs exhibited typical light response curves, and the shape of the curves was similar to those of single leaves. The light compensation point and respiration rate of BLSs were higher than those of single leaves, while the apparent quantum efficiency of BLSs was lower. Compared with single leaves, the duration of the photosynthetic function of BLSs was longer. Increasing plant density decreased the gas exchange rate per unit BLS more significantly under field conditions. There was a better linear correlation between the net CO2 assimilation rate, respiration rate of BLSs and boll biomass. Therefore, we think that the gas exchange of BLSs can better reveal the changes in photosynthetic function of BLSs and boll development. This provides a new basis for analyzing the mechanism and regulation of cotton yield formation.

Single boll weight depends on photosynthetic function of boll-leaf system in field-grown cotton plants under water stress.

Cotton has many leaves and even more bolls, which results in a complicated source-sink relationship. Under water stress, the single boll weight (SBW) of cotton remains relatively stable, while both the leaf area and leaf photosynthetic rate decrease greatly. It is therefore difficult to understand how the formation of SBW is regulated under water stress solely by considering single-leaf photosynthesis. Considering the cotton boll-leaf system (BLS: including the main-stem leaf, sympodial leaves, and non-leaf organs) as the basic unit of the cotton canopy, we speculated that the formation of SBW may depend on photosynthesis in the corresponding BLS under water stress. To verify this hypothesis, five water treatments were set up in the field. The results showed that with increasing water stress, the relative water content (RWC) of the main-stem and sympodial leaves decreased gradually, and the decrease in the sympodial leaves was more obvious. The SBW and the number of BLSs decreased slightly with increasing water stress, while the number of bolls per plant decreased significantly. The area of the BLS decreased gradually with increasing water stress, and the area of sympodial leaves decreased more than that of the main-stem leaves. Gas exchange showed that the photosynthetic rate of the BLS (Pn(BLS)) decreased gradually with increasing water stress. In addition, the single-leaf photosynthesis and carboxylation efficiency (CE) decreased progressively and rapidly with the increase of water stress. Compared with the main-stem leaf, the photosynthetic function of the sympodial leaf decreased more. Further analysis showed that compared with leaf photosynthetic rate, there was a better correlation between Pn(BLS) and SBW. Thus, the formation of SBW mainly depends on Pn(BLS) under water stress, and the increase of BLS to boll is also helpful to maintain SBW to some extent. In BLS, the photosynthesis of the main-stem leaf plays a very important role in maintaining the stability of SBW, while the photosynthetic performance in sympodial leaves may be regulated plastically to influence SBW.

Thirdhand smoke beliefs and behaviors among families of primary school children in Shanghai.

INTRODUCTION: There are few reports on the beliefs about thirdhand smoke in Chinese families with primary school children. This study aims to understand the beliefs about thirdhand smoke among parents or grandparents of primary school children in Shanghai and to provide an evidence base to incorporate thirdhand smoke preventative action into tobacco control interventions. METHODS: We performed a cross-sectional survey among parents and grandparents of children aged 6-13 years in the Changjiang Road Primary School and recruited 843 participants to make assessments on the 'beliefs about thirdhand smoke' (BATHS) scale. Sociodemographic details including age, gender, marital status, education level, personal income and type of home ownership (new house, secondhand house with or without redecoration) and health status of children (whether they suffered from respiratory diseases or not) were investigated. Scale assessment, univariate and multivariate analyses to explore the factors influencing the BATHS scale and subscale scores, were performed using SPSS version 22.0. RESULTS: Participants who were aged >65 years were more likely to get lower scores on the BATHS scale (OR=0.476; 95% CI: 0.311-0.728, p=0.001). Undergraduates (OR=1.190; 95% CI: 1.020-1.388, p=0.027) and graduates (OR=1.4490; 95% CI: 1.102-1.906, p=0.008) obtained higher scores. Moreover, the scores of residents living in a secondhand house with redecoration (OR=0.882; 95% CI: 0.782-0.995, p=0.041) and without redecoration (OR=0.801; 95% CI: 0.698-0.919, p=0.002) were lower compared with those of new-house owners. The scores for participants whose children suffered from respiratory diseases in the past six months (OR=1.104; 95% CI: 1.003-1.216, p=0.043) were higher than those whose children had no respiratory diseases. CONCLUSIONS: This study shows that younger people, females, those with higher incomes, and higher education levels, were more likely to believe the thirdhand smoke impacts on health and its persistence in the environment. Our findings can guide targeted actions for smoke-free home interventions.