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Magnetic reconnection is a fundamental mechanism for energy conversion in the realms of space physics, astrophysics, and plasma physics. Over the past few decades, obtaining analytical solutions for three-dimensional (3D) magnetic reconnection has remained a challenging endeavor. Due to the complexity and nonlinearity of the equations, analytical solutions can only be obtained when specific spatiotemporal distributions of magnetic fields or plasma flows are provided. Particularly, the evolution of reconnection flows in time-dependent 3D reconnection has not been analytically discussed. Additionally, quasi-steady magnetic reconnection persisting for several hours can be observed in the turbulent solar wind, which raises an important question: can steady reconnection flows theoretically exist in a time-dependent 3D magnetic reconnection model? In this study, a generalized analytical model for time-dependent kinematic 3D magnetic reconnection has been constructed. In the framework of pure analytical approach, it is firstly demonstrated that steady reconnection outflows can theoretically exist within a time-varying magnetic field. We have also analytically discussed the possibility of the existence of quasi-steady reconnection flows in 3D magnetic reconnection for turbulent magnetic fields in the solar wind. These findings broaden our understanding of the stability and necessary conditions for time-dependent 3D magnetic reconnection, offering new insights into quasi-steady reconnection phenomena in real cosmic environments. [ABSTRACT FROM AUTHOR]

Background: To evaluate the value of six tumor markers including squamous cell carcinoma antigen (SCCA), cytokeratin 19 fragment (CYFRA21-1), carcinoembryonic antigen (CEA), glycoconjugate antigen 125 (CA125), neuron-specific enolase (NSE), along with gastrin-releasing peptide precursor (ProGRP) in the diagnosis and pathological staging of lung cancer (LC) alone or in combination. Materials and Methods: A retrospective analysis was performed on 300 patients of which 62 cases were diagnosed as small cell lung cancer (SCLC), 105 adenocarcinoma (LUAD), 41 squamous cell carcinoma (LUSC) and 92 large cell lung cancer (LCLC) by histopathology. Another 364 patients with benign lung disease in the same period were chosen for the benign lung disease group. Results: The detection results of 6 tumor markers in serum of LC, SCCA, NSE and ProGP patients with different pathological types were higher compared with lung benign lesions group (P<0.01). LC can be separated into SCLC along with non-Small cell lung cancer (NSCLC) by NSE+ProGRP combination. The detection rate of lung squamous cell carcinoma by SCCA+ cytokeratin 19 fragment (CYFRA21-1) was higher than that by CEA+CA125 combination for adenocarcinoma. The combined determination of NSE and ProGRP was highly sensitive to SCLC. In NSCLC, the combined detection of SCC-Ag and CYFRA21-1 showed high sensitivity to LUSC. CEA+CA125 combined detection was highly sensitive to LUAD. Conclusion: The combined determination of NSE and ProGRP was highly sensitive to SCLC. CEA+CA125 combined detection was highly sensitive to LUAD, and SCCA+CYFR21-1+CEA+CA125 was the best combined detection analysis of multiple indexes. [ABSTRACT FROM AUTHOR]

The last two decades have witnessed two large-scale pandemics caused by coronaviruses, including severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS). At the end of 2019, another novel coronavirus, designated as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), hit Wuhan, a city in the center of China, and subsequently spread rapidly to the whole world. Latest reports revealed that more than 800 thousand people in over 200 countries are involved in the epidemic disease by SARS-CoV-2. Due to the high mortality rate and the lack of optimum therapeutics, it is crucial to understand the biological characteristics of the virus and its possible pathogenesis to respond to the SARS-CoV-2. Rapid diagnostics and effective therapeutics are also important interventions for the management of infection control. However, the rapid evolution of SARS-CoV-2 exerted tremendous challenges on its diagnostics and therapeutics. Therefore, there is an urgent need to summarize the existing research results to guide decision-making on the prioritization of resources for research and development. In this review, we focus on our current understanding of epidemiology, pathogenesis, diagnostics and therapeutics of coronavirus disease 2019 (COVID-19). [ABSTRACT FROM AUTHOR]

Femoral head necrosis (FHN) is a metabolic cartilage disease of rapidly growing broilers. The aim of the present study was to investigate the role of basic fibroblast growth factor (bFGF) in the apoptotic processes associated with FHN. Broilers were selected and categorized based on clinical examination in 3 groups: healthy, femoral head separation, or femoral head separation with growth plate lacerations. Hematoxylin and eosin staining showed fewer chondrocytes in the resting zone of the growth plates when FHN occurred. Moreover, the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay revealed a significant increase in chondrocyte apoptosis. Further-more, immunohistochemical assays and real-time quantitative PCR analysis demonstrated a decline in bFGF expression. In addition, reduced Bcl-2 mRNA expression was observed along with a corresponding increase in Bax and caspase-3 mRNA expression in FHN samples. There was a correlation between bFGF protein expression and the proportion of TUNEL-positive cells and a correlation between bFGF mRNA expression and expression of Bax, and caspase-3. The results of the study suggested that the expression of bFGF was reduced in the process of chondrocyte apoptosis, which could play an important role in the pathogenesis of FHN in chickens. [ABSTRACT FROM AUTHOR]

Femoral head necrosis (FHN) is a common disorder in fast-growing broilers in the poultry industry, but the pathogenesis of FHN has not been clarified completely. In the present study, glucocorticoid (GC) administration was used to induce FHN in broilers. Compared with normal birds, histopathology showed that the length of the articular cartilage of GC-induced FHN broilers was thicker while the proliferative zone and prehypertrophic zone were obviously thinner. Moreover, hematoxylin and eosin (HE) staining showed the apoptotic chondrocyte in the growth plate of the femoral head in FHN-affected birds. Bone parameters also decreased significantly in GC-induced FHN broilers. In addition, as for the mRNA expression, GC-induced FHN broilers had an apparent reduction in Col-II, Col-X, and Bcl-2 but a significant promotion of Caspase-3, Caspase-9, ASK-1, and JNK-1 when compared with the normal birds. It showed glucocorticoid induced FHN in broilers by affecting the proliferation, differentiation, and apoptosis of chondrocytes accompanying the retarding of bone growth. [ABSTRACT FROM AUTHOR]

Objectives: The Chinese Government claims that China's health policy is primarily focused on prevention. However, this does not appear to be the case. Researchers with an interest in China's health policy may be aware that the Chinese Government launched a health reform in 2009 to improve the health status of the entire population by 2020. This health reform has been in place for 7 years, and only 4 years now remain to achieve the overall objectives by 2020. This study analyzed the main inputs and outputs of China's health reform in order to identify the main problems and highlight the major challenges. It is hoped that this study will provide some reference for health reform in China and other developing countries. Study design: This study focused on health, with human resources and healthcare costs as the main input indicators, and 2-week prevalence of illness and prevalence of non-communicable diseases as the main output indicators. By longitudinal comparison of real data from 2009 to 2014, the effects of China's health reform were analyzed to identify the main challenges, enabling suggestions to be made for future reference. Methods: This was a retrospective analysis of empirical data. Data were collected between 2009 and 2014 as follows: (1) data on the distribution of healthcare professionals were collected from the Statistical Bulletin of China's Health Development, issued by the National Health and Family Planning Commission every year between 2009 and 2014; (2) data on government health expenditure were obtained from the Annual National Public Fiscal Expenditure Data, released by the Financial Ministry of the People's Republic of China from 2009 to 2014; (3) data on the prevalence of chronic diseases, 2-week prevalence of illness, residents' medical service demands, and utilization of health services were obtained from the Fourth and Fifth National Health Care Surveys in 2008 and 2013; and (4) data on total healthcare expenditure, medical expenditure and out-of-pocket payments were obtained from the 2015 China Statistical Yearbook. Results: From 2009 to 2014, China's healthcare human resources were distributed primarily in hospitals that focus on providing treatment. By 2014, 62.5% of the health professionals and technical personnel were distributed in hospitals. From 2009, the Chinese Government spent more money on health care than previously, with approximately 67% spent on disease treatment and 14.19% spent on disease prevention. However, the 2-week prevalence of illness increased by 5.2 percentage points, and the prevalence of chronic diseases increased by 9 percentage points. Meanwhile, residents' out-of-pocket payments for health care were as high as 50.61% of the total healthcare expenditure and were particularly high in rural areas. Conclusion: China should adjust the direction of its health reform as soon as possible to focus on improving health status rather than treatment of disease. In the future, as China's population ageing trend intensifies, China must take effective measures or the country's non-communicable disease rates will continue to increase. To meet this challenge, China's health reform should take effective measures to control the rising trend of the incidence of non-communicable diseases. First, China should focus on the core goal of its health reform policy, which is disease prevention. Second, China should focus on strengthening public health systems to effectively prevent and control key epidemic diseases. Third, China should increase the number of public health personnel, improve the level of education and training of public health personnel and increase the input of funds into the field of public health as soon as possible. [ABSTRACT FROM AUTHOR]

Hepatic encephalopathy (HE) is one of the severe complications of decompensated stage cirrhosis that causes cerebral dysfunction due to hepatic insufficiency and/or portosystemic shunts, and it usually manifests as a wide spectrum of neurological or psychiatric abnormalities ranging from subclinical alterations to coma. The pathogenesis of HE is complex, although ammonia toxicity, oxidative stress, inflammation, intestinal dysbiosis, and others among them mainly play an important role. The treatment for HE lacks specific drugs, and the current available drugs include non-absorbable disaccharides (lactulose), antibiotics (rifaximin), and other therapies (oral branched-chain amino acids, intravenous injection of L-ornithine-L-aspartic acid, probiotics). Recent research has shown that human albumin is a safe and effective treatment for HE, improving not only cognitive function but also enhancing patients' quality of life.

Objective: The objective of this study was to assess the incidence of tuberculosis (TB) and find the risk factors of TB patients with a high burden of TB in socioeconomic level, the high level of TB incidence and the great changes of economic and social factors, explore the possible factors, construct scientific and robust prediction model, and analyse whether the task of stopping TB can be accomplished by the expected global deadline., Study Design: This was an ecological study., Methods: Descriptive analysis, spatial and space-time scan, correlation analysis, and regression analysis were carried out, based on cases of TB in Sichuan Province and ecological data from 2006 to 2017, to explore the characters of TB and ecological factors, using the transfer function-noise model to forecast the trend of TB until 2035., Results: Factors affecting the incidence of TB, increasing per capita green area, reporting status of TB among Tibetans and Yi minorities, comprehensive treatment management, total cost of TB per capita for urban residents, proportion of males with high school education, 20 to 20 h of 24-h accumulated precipitation, reducing HIV at the same time as AIDS deaths, the increase in the proportion of males in junior high school education, and the increase in the number of registered TB cases can reduce the incidence of TB., Conclusions: There was concentration mainly on enhanced control of the environment and society measures, helpful in guiding government planning to control TB. Reinforcement is required to reduce the TB of population aged 15-24 and aged 25-64 in socioeconomic level by 2035., (Copyright © 2023. Published by Elsevier Ltd.)

Importance: Of 123 identified isolates from the fruit surface, C. tropicalis was the most frequently found species, followed by Meyerozyma caribbica and Candida krusei . All three fluconazole-resistant C. tropicalis were non-susceptible to voriconazole and belonged to the same predominant genotype of azole-resistant C. tropicalis causing candidemia in patients in Taiwan. Our findings provide evidence that fruit should be washed before eaten not only to remove chemicals but also potential drug-resistant pathogenic microbes, especially for immunocompromised individuals. To keep precious treatment options in patients, we not only continuously implement antimicrobial stewardship in hospitals but also reducing/stopping the use of agricultural fungicide classes used in human medicine., Competing Interests: The authors declare no conflict of interest.

Objective: To investigate the safety and efficacy of total pelvic exenteration (TPE) for treating late complications of radiation-induced pelvic injury. Methods: This was a descriptive case series study. The inclusion criteria were as follows: (1) confirmed radiation-induced pelvic injury after radiotherapy for pelvic malignancies; (2) late complications of radiation-induced pelvic injury, such as bleeding, perforation, fistula, and obstruction, involving multiple pelvic organs; (3) TPE recommended by a multidisciplinary team; (4) patient in good preoperative condition and considered fit enough to tolerate TPE; and (5) patient extremely willing to undergo the procedure and accept the associated risks. The exclusion criteria were as follows: (1) preoperative or intraoperative diagnosis of tumor recurrence or metastasis; (2) had only undergone diversion or bypass surgery after laparoscopic exploration; and (3) incomplete medical records. Clinical and follow-up data of patients who had undergone TPE for late complications of radiation-induced pelvic injury between March 2020 and September 2022 at the Sixth Affiliated Hospital of Sun Yat-sen University were analyzed. Perioperative recovery, postoperative complications, perioperative deaths, and quality of life 1 year postoperatively were recorded. Results: The study cohort comprised 14 women, nine of whom had recto-vagino-vesical fistulas, two vesicovaginal fistulas, one ileo-vesical fistula and rectal necrosis, one ileo-vesical and rectovaginal fistulas, and one rectal ulcer and bilateral ureteral stenosis. The mean duration of surgery was 592.1±167.6 minutes and the median blood loss 550 (100-6000) mL. Ten patients underwent intestinal reconstruction, and four the Hartmann procedure. Ten patients underwent urinary reconstruction using Bricker's procedure and 7 underwent pelvic floor reconstruction. The mean postoperative hospital stay was 23.6±14.9 days. Seven patients (7/14) had serious postoperative complications (Clavien-Dindo IIIa to IVb), including surgical site infections in eight, abdominopelvic abscesses in five, pulmonary infections in five, intestinal obstruction in four, and urinary leakage in two. Empty pelvis syndrome (EPS) was diagnosed in five patients, none of whom had undergone pelvic floor reconstruction. Five of the seven patients who had not undergone pelvic floor reconstruction developed EPS, compared with none of those who had undergone pelvic floor reconstruction. One patient with EPS underwent reoperation because of a pelvic abscess, pelvic hemorrhage, and intestinal obstruction. There were no perioperative deaths. During 18.9±10.1 months of follow-up, three patients died, two of renal failure, which was a preoperative comorbidity, and one of COVID-19. The remaining patients had gradual and significant relief of symptoms during follow-up. QLQ-C30 assessment of postoperative quality of life showed gradual improvement in all functional domains and general health at 1, 3, and 6 months postoperatively (all P <0.05). Conclusions: TPE is a feasible procedure for treating late complications of radiation-induced pelvic injury combined with complex pelvic fistulas. TPE is effective in alleviating symptoms and improving quality of life. However, the indications for this procedure should be strictly controlled and the surgery carried out only by experienced surgeons.

Pelvic radiation injury can potentially involve multiple pelvic organs, and due to its progressive and irreversible nature, its late stage can be complicated by fistulas, perforations, obstructions and other complications involved multiple pelvic organs, which seriously affect the long-term survival and the quality of life of patients. As a multidisciplinary surgical approach, pelvic exenteration has potential application in the treatment of late complications of pelvic radiation injury by completely removing the irradiated lesion, relieving symptoms and avoiding recurrence of symptoms. In clinical practice, we should advocate the concept of "pelvic radiation injury", emphasize multidisciplinary collaboration, fully evaluate the overall status of patients, primary tumor and pelvic radiation injury. We should follow the principles of "damage-control" and "extended resection", and follow the principle of enhanced recovery after surgery to achieve the goal of ensuring the surgical safety, relieving patients' symptoms and improving patients' quality of life and long-term survival.

For elective surgery of colorectal cancer, current evidence supports preoperative mechanical bowel preparation combined with oral antibiotics. Meanwhile, for patients with varied degrees of intestinal stenosis, individualized protocol is required to avoid adverse events. We hereby summarize recent high-quality evidences and updates of guidelines and consensus, and recommend stratified bowel preparation based on the clinical practice of our institute as follows. (1) For patients with unimpaired oral intake, whose tumor can be passed by colonoscopy, mechanical bowel preparation and oral antibiotics are given. (2) For patients without symptoms of bowel obstruction but with impaired oral intake or incomplete colonoscopy due to tumor-related stenosis, small-dosage laxative is given for several days before surgery, and oral antibiotics the day before surgery. (3) For patients with bowel obstruction, mechanical bowel preparation or enema is not indicated. We proposed this evidence-based, individualized protocol for preoperative bowel preparation for the reference of our colleagues, in the hope of improving perioperative outcomes and reducing adverse events.

We used Bayesian modeling to aggregate experiments investigating infants' sensitivity to native language phonotactics. Our findings were based on data from 83 experiments on about 2000 infants learning 8 languages, tested using 4 different methods. Our results showed that, unlike with artificial languages, infants do exhibit sensitivity to native language phonotactic patterns in a lab setting. However, the exact developmental trajectory depends on the phonotactic pattern being tested. Before 8 months, infants tuned into non-local dependencies between vowels: specifically, vowel harmony. Between 8- and 10-months, infants demonstrated a consistent sensitivity to both local dependencies and non-local consonant dependencies. Sensitivity to non-local vowel dependencies that are not based on harmony emerged only after 10-months. These findings provide a benchmark for future experimental and computational research on the acquisition of phonotactics., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: To investigate the efficacy and safety of diseased bowel resection and diversion enterostomy in the treatment of late severe complications of chronic radiation-induced late rectal injury (RLRI). Methods: Studies about comparison of diseased bowel resection and diversion enterostomy in the treatment of late severe complications of chronic RLRI were screened and retrieved from databases, including PubMed, EMBASE, Scopus, Web of Science, Cochrane Library, CNKI, VIP, CBM and Wanfang. The following terms in Chinese were used to search [Title/Abstract]: radiation-induced intestinal injury, radiation proctitis, surgery. The following English terms were used to search: Radiation-induced intestinal injury, Bowel injury from radiation, Radiation proctitis, Surgery, Colostomy. Literature inclusion criteria: (1) studies with control groups, published at home and abroad publicly, about the postoperative effects of diseased bowel resection vs. diversion enterostomy on RLRI patients with late severe complications; (2) the period of the study performed in the literatures must be clear; (3) patients at the preoperative diagnosis for RLRI with refractory bleeding, narrow, obstruction, perforation or fistula, etc.; (4) diseased bowel resection included Hartmann, Dixon, Bacon and Parks; diversion enterostomy included colostomy and ileostomy; (5) if the studies were published by the same institution or authors at the same time, the study with the biggest sample size was chosen; studies conducted in different time with different subjects were simultaneously included; (6) at least one prognostic indicator of the following parameters should be included: the improvement of symptoms, postoperative complications, mortality, and reversed stomas rate. The stoma reduction rate was defined as the ratio of successful closure of colostomy after diseased bowel resection and diversion enterostomy. The method of direct calculation or the method of convert into direct calculation were used for stoma reduction rate. Exclusion criteria: (1) a single-arm study without control group; (2) RLRI patients did not undergo diseased bowel resection or diversion enterostomy at the first time; (3) RLRI patients with distant metastasis; (4) the statistical method in the study was not appropriate; (5) the information was not complete, such as a lack of prognosis in the observational indexes. After screening literatures according to criteria, data retrieval and quality evaluation were carried out. Review Manager 5.3 software was used for Meta-analysis. Sensitivity analysis was used to exam the stability of results. Funnel diagram was used to analyze the bias of publication. Results: A total of 11 literatures were enrolled, including 426 RLRI patients with late severe complications, of whom 174 underwent diseased bowel resection (resection group) and 252 underwent diversion enterostomy (diversion group), respectively. Compared with diversion group, although resection group had a higher morbidity of complication (35.1% vs. 15.9%, OR=2.67, 95% CI: 1.58 to 4.53, P <0.001), but it was more advantageous in symptom improvement (94.2% vs. 64.1%, OR=6.19, 95% CI: 2.47 to 15.52, P <0.001) and stoma reductions (62.8% vs. 5.1%, OR=15.17, 95% CI: 1.21 to 189.74, P =0.030), and the differences were significant (both P <0.05). No significant difference in postoperative mortality was found between the two groups (10.1% vs. 18.8%, OR=0.74, 95% CI: 0.21 to 2.59, P =0.640). There were no obvious changes between the two groups after sensitivity analysis for the prognostic indicators (the symptoms improved, postoperative complications, mortality, and reversed stomas rate) compared with the meta-analysis results before exclusion, suggesting that the results were robust and credible. Funnel diagram analysis suggested a small published bias. Conclusions: Chronic RLRI patients with late severe complications undergoing diseased bowel resection have higher risk of complication, while their long-term mortality is comparable to those undergoing diversion enterostomy. Diseased bowel resection is better in postoperative improvement of symptoms and stoma reduction rate.

Recent studies have indicated that the nanoindentation measured stiffness of carcinoma adherent cells is in general lower than normal cells, thus suggesting that cell stiffness may serve as a bio-marker for carcinoma. However, the proper establishment of such a conclusion would require biophysical understanding of the underlying mechanism of the cell stiffness. In this work, we compared the elastic moduli of the actin cytoskeletons of Hey A8 ovarian carcinoma cells with and without metastasis (HM and NM), as measured by 2D atomic force microscopy (AFM) with low-depth nanoindentation via a rate-jump method. The results indicate clearly that HM cells showed lower actin cytoskeleton stiffness atop of their nucleus position and higher actin cytoskeleton stiffness at their rims, compared to NM cells, suggesting that the local stiffness on the cytoskeleton can reflect actin filament distribution. Immunofluorescence staining and scanning electron microscopy (SEM) also indicated that the difference in stiffness in Hey A8 cells with different metastasis is associated with their F-actin rearrangement. Finite-element modelling (FEM) shows that a migrating cell would have its actin filaments bundled together to form stress fibers, which would exhibit lower indentation stiffness than the less aligned arrangement of filaments in a non-migrating cell. The results here indicate that the actin cytoskeleton stiffness can serve as a reliable marker for grading the metastasis of adherent carcinoma cells due to their cytoskeleton change and potentially predicting the migration direction of the cells., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A drug-free procedure for killing malignant cells in a cell-type specific manner would represent a significant breakthrough for leukemia treatment. Here, we show that mechanically vibrating a cell in a specific oscillation condition can significantly promote necrosis. Specifically, oscillating the cell by a low-power laser trap at specific frequencies of a few Hz was found to result in increased death rate of 50% or above in different types of myelogenous leukemia cells, while normal leukocytes showed very little response to similar laser manipulations. The alteration of cell membrane permeability and cell volume, detected from ethidium bromide staining and measurement of intracellular sodium ion concentration, together with the observed membrane blebbing within 10min, suggest cell necrosis. Mechanics modelling reveals severe distortion of the cytoskeleton cortex at frequencies in the same range for peaked cell death. The disruption of cell membrane leading to cell death is therefore due to the cortex distortion, and the frequency at which this becomes significant is cell-type specific. Our findings lay down a new concept for treating leukemia based on vibration induced disruption of membrane in targeted malignant cells., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Gossypium tomentosum and G. darwinii are wild allotetraploid cotton species, characterized by many excellent traits, including fiber fineness, drought tolerance, and Fusarium and Verticillium wilt resistance. Based on the construction of F2 linkage groups of G. hirsutum x G. tomentosum and G. hirsutum x G. darwinii, two genetic linkage maps were compared. As a result, we found a total of seven inverted fragments on chr02, chr05, chr08, chr12, chr14, chr16, and chr25, and three translocated fragments on chr05, chr14, and chr26. In addition, comparison of the inverted and translocated fragments revealed that the orientation of four of seven markers in G. tomentosum were consistent with G. hirsutum or G. raimondii. The orientation of one of seven inverted markers of G. darwinii was consistent with G. hirsutum, and the orientation of one of three translocated markers of G. tomentosum was consistent with G. raimondii. These results indicate that, in comparison to G. darwinii, G. tomentosum has a closer genetic relationship to G. hirsutum. These findings will be important for our understanding on the genome structure of G. tomentosum and G. darwinii, and set the scene for further in-depth genome research such as fine mapping, tagging genes of interest from wild relatives, and evolutionary study., Competing Interests: The authors declare no conflict of interests.

Cotton is one of the most important natural fiber crops in the world. Its growth and yield is greatly limited by drought. A quantitative trait locus (QTL) analysis was therefore conducted to investigate the genetic basis of drought tolerance in cotton (Gossypium spp) using 188 F2:3 lines developed from an inter-specific cross between a wild cotton species, G. tomentosum, and an upland cotton, G. hirsutum (CRI-12). A genetic map was constructed using 1295 simple sequence repeat markers, which amplified 1342 loci, distributed on 26 chromosomes, covering 3328.24 cM. A field experiment was conducted in two consecutive years (2014 and 2015) and 11 morphological and physiological traits were recorded under water-limited (W1)/well-watered (W2) regimes at three growth stages (bud, flowering, and full boll). The traits measured included chlorophyll content, plant height, leaf area, leaf number, leaf fresh weight, leaf dry weight, boll weight, number of bolls per plant, and the number of fruiting branches. Sixty-seven and 35 QTLs were found under the W1 and W2 conditions, respectively. Of these, the majority exhibited partial dominance or over-dominance genetic effects for increasing the trait values. Four consistent QTLs were found under the W1 treatment on chromosomes 5, 8, 9, and 16, whereas no consistent QTL was found in W2. Thirteen QTL clusters were also identified on nine chromosomes (2, 3, 5, 6, 9, 14, 15, 16, and 21). These results will help to elucidate the genetic basis of drought tolerance in cotton.

Gossypium tomentosum is a wild allotetraploid species with the (AD)5 genome. It is characterized by many useful traits including finer fiber fineness, drought tolerance, and Fusarium and Verticillium resistance. We constructed the first bacterial artificial chromosome library for Gossypium tomentosum. With high quality and broad coverage, this library includes 200,832 clones, with an average insert size of about 122 kb and fewer than 3% empty clones. Our library is approximately 10-fold the size of the (AD)5-genome (2400 Mb) and provides a 99.7% probability of isolating genes of interest or their sequences. Seven of eight simple sequence repeats markers that are located on five different chromosomes and linked with resistance to Verticillium wilt could amplify the 50 superpools and obtained one to five hits. This high capacity library will be an important genomic resource for classifying and analyzing the evolution of allotetraploid cotton species as well as for isolating disease-resistance and drought-tolerance genes.

Simple sequence repeat techniques were used to identify the genetic diversity of 101 Gossypium arboreum accessions collected from India, Vietnam, and the southwest of China (Guizhou, Guangxi, and Yunnan provinces). Twenty-six pairs of SSR primers produced a total of 103 polymorphic loci with an average of 3.96 polymorphic loci per primer. The average of the effective number of alleles, Nei's gene diversity, and Shannon's information index were 0.59, 0.2835, and 0.4361, respectively. The diversity varied among different geographic regions. The result of principal component analysis was consistent with that of unweighted pair group method with arithmetic mean clustering analysis. The 101 G. arboreum accessions were clustered into 2 groups.

Cotton is an important economic crop worldwide; its fiber, commonly known as cotton lint, is the main natural source for the textile industry. Sixty chloroplast microsatellites were identified and characterized from the complete sequence of the Gossypium hirsutum chloroplast genome using a bioinformatic approach. Twenty chloroplast microsatellite loci were polymorphic in the 66 Gossypium germplasm accessions. A total of 85 alleles were detected, with allele numbers varying from 2-7 per locus. Polymorphism information content varied from 0.02-0.66, with a mean of 0.48. Additionally, transferability of the 20 polymorphic chloroplast microsatellite primers was evaluated in other 31 Gossypium species. Sixteen markers were successfully amplified across all species tested, while the remaining 4 markers cross-amplified in most species tested. These polymorphic chloroplast microsatellite markers may be useful tool for studies of individual identification, genetic diversity, evolution, conservation genetics, and molecular breeding in Gossypium.