The Physiological Response of Apricot Flowers to Low-Temperature Stress.

The growth and development of apricot flower organs are severely impacted by spring frosts. To better understand this process, apricot flowers were exposed to temperatures ranging from 0 °C to -8 °C, including a control at 18 °C, in artificial incubators to mimic diverse low-temperature environments. We aimed to examine their physiological reactions to cold stress, with an emphasis on changes in phenotype, membrane stability, osmotic substance levels, and antioxidant enzyme performance. Results reveal that cold stress induces significant browning and cellular damage, with a sharp increase in browning rate and membrane permeability below -5 °C. Soluble sugars and proteins initially rise as osmoprotectants, but their content decreases at lower temperatures. Proline content consistently increases, suggesting a protective role. Antioxidant enzyme activities, including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX), exhibit a complex pattern, with initial increases followed by declines at more severe cold conditions. Correlation and principal component analyses highlight the interplay between these responses, indicating a multifaceted adaptation strategy. The findings contribute to the understanding of apricot cold tolerance and inform breeding efforts for improved crop resilience.

Comparison of the bone mineral density status of patients with kidney stones stratified by stone composition.

PURPOSE: Bone loss has been found to occur frequently in patients with particular metabolic disorders that are likely associated with certain kidney stone composition. Thus, we compared the bone mineral density (BMD) of patients with different kidney stone compositions. PATIENTS AND METHODS: A total of 204 consecutive patients who exhibited stone formation with calcium oxalate (CaOx), calcium phosphate (CaP), uric acid (UA), and magnesium ammonium phosphate (MAP) underwent 24 h urine test and BMD measurement. BMD was measured by dual X-ray absorptiometry at the lumbar spine (LS) and femoral neck (FN). The Z-score was used to express BMD. A BMD Z-score ≤ - 2 was defined as a diagnostic threshold for bone loss. RESULTS: Amongst the patients, 38 had an LS BMD Z-score of ≤ - 2, but only 2 had FN BMD Z-score of ≤ - 2. The group with an LS BMD Z-score of ≤ - 2 exhibited significantly larger male - female ratio, higher frequency of hypercalciuria and CaP, and lower frequency of MAP than the group with an LS BMD Z-score of > - 2. Reduced LS BMD was most remarkable in the CaP group, followed by the CaOx, UA, and MAP groups. The LS BMD Z-score of hypercalciuric patients was significantly lower than that of normocalciuric patients only in the CaP group. CONCLUSION: Patients with different kidney stone compositions presented different BMD status. Using this information may facilitate medical decision-making in patients with kidney stone who should undergone BMD earlier.

Perfect Acoustic-Vortexes Constructed by the Fourier Transform of Quasi-Bessel Beams Based on the Simplified Ring Array of Sectorial Planar Transducers.

Benefiting from the independence of the vortex radius on the topological charge (TC), the perfect acoustic-vortex (PAV) with an angular phase gradient exhibits important perspectives in acoustic applications. However, the practical implementation is still restricted by the limited accuracy and flexibility of the phase control for large-scaled source arrays. An applicable scheme of constructing PAVs by the spatial Fourier transform of quasi-Bessel AV (QB-AV) beams is developed using the simplified ring array of sectorial transducers. The principle of PAV construction is derived based on the phase modulation of the Fourier and saw-tooth lenses. Numerical simulations and experimental measurements are carried out for the ring array with the continuous and discrete phase spirals. The construction of PAVs is demonstrated by the annuli at an almost identical peak pressure with the vortex radius independent of the TC. The vortex radius is proved to increase linearly with the increase of the rear focal length and the radial wavenumber, which are determined by the curvature radii and the acoustic refractive index of the Fourier lens and the bottom angle of the saw-tooth lens, respectively. The improved PAV with a more continuous high-pressure annulus and lower concentric disturbances can be constructed by the ring array of more sectorial sources and the Fourier lens of a bigger radius. The favorable results demonstrate the feasibility of constructing PAVs by the Fourier transform of QB-AV beams and provide an implementable technology in the fields of acoustic manipulation and communication.

Resequencing and transcriptomic analysis reveal differences in nitrite reductase in jujube fruit (Ziziphus jujuba Mill.).

BACKGROUND: Jujube is a typical fruit tree species from China. 'Muzao', a cracking-susceptible cultivar, and 'Linhuang No. 1', a cracking-resistant cultivar, were selected in a previous study as contrasting research materials. Whole-genome resequencing and transcriptomic analysis of 'Linhuang No. 1' and 'Muzao' allowed the identification of differentially expressed genes with different gene structures between the two cultivars and could be helpful in explaining the differences and similarities between the two cultivars. RESULTS: Resequencing identified 664,129 polymorphic variable sites between 'Linhuang No. 1' and 'Muzao'. To determine the genetic relationship among 'Linhuang No. 1', 'Muzao' and the jujube genome reference cultivar 'Dongzao', the characteristic polymorphic variable sites were analysed by principal component analysis. The genetic relationship between 'Linhuang No. 1' and 'Muzao' was closer than that of either variety and 'Dongzao'. Nineteen differentially expressed genes were identified by combining transcriptomic analysis with resequencing analysis. LOC107427052 (encoding a nitrite reductase) was identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis for further study. The identified insertion was not in the domain region of the LOC107427052 gene coding sequence (CDS) region and was verified by the finding that the insertion did not affect translation of the protein. The LOC107427052 gene expression levels, nitrite reductase activities and nitrite contents of 'Muzao' were significantly higher than the corresponding values of 'Linhuang No. 1' at the young fruit stage. There was no significant difference in the quantity of the product of nitrite reductase, namely, ammonia, between the two cultivars. CONCLUSIONS: The present study was the first to explore the differences between different jujube cultivars ('Linhuang No. 1' and 'Muzao') by combining genome resequencing and transcriptomics. LOC107427052 (encoding a nitrite reductase) was characterized by KEGG enrichment analysis. The insertion in the CDS region of the LOC107427052 gene provides a new direction for the study of nitrogen metabolism in jujube. Our study has laid a foundation for the comparative analysis of nitrite metabolism between the jujube cultivars 'Linhuang No. 1' and 'Muzao'.

Comparative analysis of transcriptomic profiling to identify genes involved in the bulged surface of pear fruit (Pyrus bretschneideri Rehd. cv. Yuluxiangli).

Pear (Pyrus spp.) belongs to the genus Pyrus, in the family Rosaceae. Some varieties of pear fruit exhibit bulged surface, which seriously affects the quality and commodity value of the pear fruit. In this study, we performed anatomical, physiological, and transcriptomic analysis to explore the mechanism of paclobutrazol (PBZ) on the bulged surface of pear fruit. The vascular bundles of flesh were more evenly distributed, and the fruit cells were more compactly arranged and smaller in size treated with PBZ. However, the auxin (IAA) content of flesh was decreased in the treated group. Furthermore, the GO and KEGG analysis of differentially expressed genes (DEGs) showed that auxin, phenylpropanoid metabolic pathways, and transcriptional factor genes were significantly enriched on the relieved bulged surface of pear fruit. And it was analyzed that some genes contained auxin responded cis-elements from the selected DEGs in the promoter region. We conclude that PBZ plays a negative role in cell division, cell elongation, and vascular bundle development on the bulged surface of pear fruit through the involvement of auxin-related genes. This study will provide a theoretical basis for the regulation of the bulged surface of pear fruit by a growth retardant agent. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s12298-021-00929-z) contains supplementary material, which is available to authorized users.

Systematic analysis of the OFP genes in six Rosaceae genomes and their roles in stress response in Chinese pear (Pyrus bretschneideri).

OVATE family proteins (OFPs) are the plant-specific transcription factors, and have significant functions in regulating plant growth, development and resistance. The OFP genes have been investigated in several plants, but they still lack a systematic analysis of OFP genes in Chinese pear and some other five Rosaceae genomes. Here, 28 PbrOFPs were identified within Chinese pear and compared them with those of other five Rosaceae genomes. Evolutionary tree revealed that all OFP genes from six Rosaceae genomes were divided into eight groups. Seventeen conserved microsynteny regions were detected in Chinese pear genome, suggested that these PbrOFP genes might be considered to have originated from the large-scale duplication events., indicating these PbrOFP genes might contain specialized regulatory mechanisms in these tissues, such as flower, ovary and fruit. Remarkably, two PbrOFP genes (Pbr010426.1 and Pbr010427.1) were up-regulated under Venturia nashicola treatment, and five PbrOFP genes were up-regulated under PEG treatment, suggesting that these genes might play crucial roles in defence to environmental stresses. Our data presented a systematic analysis and might aid in the selection of appropriate PbrOFPs for further functional studies in Chinese pear, especially in response to the mechanism of biotic and abiotic stresses.

Wax composition and concentration in jujube (Ziziphus jujuba Mill.) cultivars with differential resistance to fruit cracking.

Fruit cracking is a key problem restricting the development of the jujube (Ziziphus jujuba) industry, and is closely related to the distribution of the wax layer on the surface of the fruit. Three jujube cultivars with different levels of cracking resistance, namely 'Popozao', 'Banzao', and 'Hupingzao', were selected for comparison. Cracks on the cuticular membrane (CM) of 'Hupingzao' widened and deepened during the coloring period. The wax level of highly cracking-resistant 'Popozao' was significantly higher than that of 'Hupingzao' during the fruit coloring period. The fruit wax composition of the three jujube cultivars were quite similar, consisting mainly of alkanes, triterpenoids, aldehydes, amines, phenols, esters, ketones, fatty acids, primary alcohols, and other, unclassified compounds. Fatty acids, primary alcohols, and alkanes were the predominant fruit wax compounds of the three cultivars. We further analyzed the carbon chain length of aliphatic compounds and found that the concentration of fatty acids in 'Popozao' was significantly lower than that in 'Banzao' and 'Hupingzao' during the coloring period. Moreover, C28-30 were the most abundant primary alcohols during fruit development. Highly cracking-resistant cultivar 'Popozao' contains more very-long-chain alkanes and aldehydes (carbon atom >20) than 'Banzao' and 'Hupingzao' during the coloring period. In addition, we assessed the expression levels of 11 genes involved in fatty acid biosynthesis, elongation, and degradation, and in wax biosynthesis. Gene expression analysis indicated that KCS1, CER1, CYP86B1, and CYP86A play crucial roles in wax formation on jujube fruit. In conclusion, fruit cracking was correlated with whether wax synthesis is coordinated with fruit enlargement and'Popozao' has a stronger ability to synthesize very-long-chain alkanes and aldehydes. Understanding the diff ;erences in the cuticular wax and the activities of the corresponding genes in jujube cultivars with different sensitivities to cracking will provide a specific way to prevent fruit cracking.

Incidence and correlates of HIV and syphilis in a prospective cohort of men who have sex with men in Mianyang, China, over a 36-month period.

UNLABELLED: Background Estimates for the HIV/AIDS epidemic from the China Ministry of Health show that the epidemic is spreading rapidly among men who have sex with men (MSM). METHODS: Respondent-driven sampling (RDS) was adapted in 2009 and snowball sampling was adapted to supplement the number of participants in 2010 and 2011. Interviewer-administered questionnaires and blood tests were conducted to confirm enrolment eligibility of participants. RESULTS: A total of 725 HIV-negative participants were included into the cohort study. The cohort had a HIV incidence density of 5.6 (95% CI: 3.9-7.3)/100 person-years (PY) and a syphilis incidence density of 5.6 (95% CI:3.7-7.6)/100 PY. Age ≤20 years (21-25 years, hazard ratio (HR)=0.32, 95%CI: 0.11-0.95/≥26 years, HR=0.17, 95%CI: 0.05-0.66), having not participated in peer education in the past year (HR=2.96, 95%CI: 1.19-7.35), seeking male sexual partners in a public washroom/park (HR=3.61, 95%CI: 1.03-12.47), being currently infected with syphilis (HR=3.21, 95%CI: 1.31-7.91), having sex partners aged ≥30 years (HR=3.40, 95%CI: 1.11-10.39) and having more than four male sexual partners within the past 6 months (HR=3.34, 95%CI: 1.24-9.04) were found to be risk factors for HIV seroconversion (each P<0.05). Being married (HR=2.38, 95%CI: 1.04-5.46), having not participated in peer education in the past year (HR=2.28, 95%CI: 1.08-4.82), having limited HIV/AIDS knowledge (HR=4.28, 95%CI: 1.94-9.43) and having a sexually transmitted disease infection in the past 6 months (HR=4.74, 95%CI: 1.83-12.30) were identified as factors for syphilis infection (each P<0.05). CONCLUSION: The incidence rates of HIV and syphilis in Mianyang City reamained high in the cohort of MSM for 36 months. Increased attention should be given to this serious epidemic, and appropriate interventions should be implemented to address MSM-specific issues in order to prevent HIV and syphilis infection in China.

[Analysis on the intention of marriage and the influence factors among unmarried men who have sex with men].

OBJECTIVE: To understand the intention on marriage and the related influence factors among men who have sex with men (MSM). METHODS: Using the snowball sampling method, an anonymous questionnaire survey was achieved by recruiting MSM. RESULTS: A total number of 308 people were included in this survey, the numbers of 'planning to get married' was 34.4%, intended not to get married accounted for 65.6%; and the average age of intending to marry was (28.1 ± 3.3) years old. The intended marriage partners were ordinary women accounted for 83.8%, while another 16.2% were lesbians. Reasons for getting married were under social pressure (65.1%), under family pressure (12.3%), and under personal desire (22.6%). Those who intended to remain contact with gay after marriage accounted for 66.7%, with 16.2% did not and those were not sure accounted for 17.1%. Using the multivariate analysis method, results showed that the independent factors for intention of marriage were: age, sexual orientation, registration for residency, cumulative numbers of regular sexual partners, number of anal sex in the last week, proportion of intention to get married was relatively low among those who were over 35 years of age and their residence of registration were in the city. However those who were bisexual, with uncertain sexual orientation, and with low cumulative numbers of regular sexual partners as well as less anal sex in the past week, occupied higher proportions. CONCLUSION: MSM population under our current study showed a high percentage on marriage intention which posed serious challenges to the society and families. AIDS prevention on this population seemed to be impacted by demographic characteristics and sexual behavior.