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Yiyang Dahegu rice (YyDHG) is an important agricultural specialty of Yiyang County, Jiangxi Province, and it is also a significant component of the local cultural and economic development. In this experiment, 89 samples of Dahegu rice (DHG) were collected from Jiangxi Province, including 52 samples of YyDHG and 37 samples of DHG from other regions within Jiangxi Province (oDHG). Comprehensive analysis was conducted using polyacrylamide gel electrophoresis, field phenotypic observation, population structure analysis and quality analysis. The results of variety identification indicated that the 89 samples actually comprised 52 distinct varieties, including 19 varieties of YyDHG. Population analysis has revealed rich genetic diversity among DHG varieties within Jiangxi Province, yet no significant subpopulation differentiation was observed between YyDHG and oDHG. Quality experiments demonstrated that YyDHG exhibits significant differences in appearance quality from oDHG, but no notable differences in milling quality or cooked taste and flavour. This suggests that the competitiveness of YyDHG in the market may not entirely depend on its unique quality characteristics, but rather more on its cultural value and brand effect. This experiment conducted a comprehensive analysis of the variety characteristics, genetic diversity and quality traits of YyDHG. Not only does it provide a scientific basis for the breeding and germplasm resource conservation of YyDHG, but it also holds positive implications for promoting the development of its industry.
Globally, numerous infertile couples have been assisted by extensive research on mammalian fertilization and the rapid development of Assisted Reproductive Technology (ART). However, 5%–15% of the couples that are selected for in vitro fertilization (IVF) experience a total fertilization failure (TFF), where no zygotes develop despite oocytes and semen parameters appear to be normal. Notably, an essential early event in fertilization is the binding of spermatozoa to the oocyte’s external envelope, which followed by the spermatozoa-oocyte fusion. Meanwhile, oocyte activation is a crucial cellular process necessary to block polyspermy and start the development of the zygote. Improper membrane fusion of gametes has been demonstrated to be one of the mechanisms of TFF. Moreover, considering the large amount of research on sperm proteins in recent years, thus in this review, we characterize the role and molecular mechanisms of sperm proteins in the three key processes of gamete adhesion and fusion and oocyte activation, which would provide a comprehensive understanding of the role of sperm proteins in fertilization in mammals and a favourable reference for future studies in assisted reproduction due to FF.
Research on the association between the Chinese visceral adiposity index (CVAI) and hyperuricaemia (HUA) is scarce, and whether the association differs by sex is unclear. This research aimed to explore sex-specific associations between CVAI and HUA and to compare CVAI’s predictive performance with other adiposity indices using data from 22 171 adults (30–79 years) in the China Multi-Ethnic Cohort study (Chongqing region). The prevalence of HUA was 20·9 % in men and 9·7 % in women. Multivariable logistic regression analyses were utilised to assess the adjusted OR and 95 % CI. After multivariable adjustment, CVAI was associated with HUA in men (OR Q4 v. Q1 = 3·31, 95 % CI 2·73, 4·03) and women (OR Q4 v. Q1 = 7·20, 95 % CI 5·12, 10·12). Moreover, significant interactions were observed between BMI and CVAI on HUA in both sexes (all Pinteraction < 0·001), with the strongest associations in those with BMI < 24·0 kg/m2. The OR (95 % CI) across different BMI groups (< 24·0, 24·0–27·9, ≥ 28·0 kg/m²) were 1·87 (1·63, 2·13), 1·65 (1·48, 1·85) and 1·30 (1·14, 1·49) for men and 2·76 (2·18, 3·51), 2·46 (1·98, 3·07) and 1·87 (1·47, 2·39) for women, respectively. Additionally, CVAI showed satisfactory predictive performance for HUA in women, with the largest area under the receiver operating characteristic curve of 0·735, but not in men (0·660). These findings suggest a close association between CVAI and HUA, particularly pronounced in those with BMI < 24·0 kg/m², and a stronger association in women than in men.
Gentiana straminea Maxim. (Gentianaceae) is an important traditional Tibetan herb that is mainly distributed on the Qinghai-Tibetan Plateau. Despite its agricultural and pharmacological importance, there remains a paucity of microsatellite markers, particularly expressed sequence tag-simple sequence repeat (EST-SSR) markers, available for this local endemic species. In this study, based on previous Illumina transcriptome data of G. straminea, a total of 96 EST-SSR markers were initially designed and tested. Thirty-two of 96 loci (33.33%) were successfully amplified and verified for validation. Among them, 10 were polymorphic and had clear bands. The polymorphism information content values were 0.09–0.799, the number of alleles per locus ranged from 3 to 14, and the levels of observed and expected heterozygosity were 0.078–0.722 and 0.238–0.884, respectively, which suggested a high level of information. Moreover, cross-amplification was successful for 10 loci in two other related species, Gentiana macrophylla Pallas and Gentiana dahurica Fischer. These EST-SSR markers provide a valuable tool for investigating the genetic diversity related to quantitative traits and population genetic studies on G. straminea and related species in sect. Cruciata Gaudin.
In this paper, we have experimentally demonstrated a high-power and high-brightness narrow-linewidth fiber amplifier seeded by an optimized fiber oscillator. In order to improve the temporal stability, the fiber oscillator consists of a composite fiber Bragg grating-based cavity with an external feedback structure. By optimizing the forward and backward pumping ratio, the nonlinear effects and stimulated Raman scattering-induced mode distortion of the fiber amplifier are suppressed comprehensively, accompanied with the simultaneous improvement of beam quality and output power. The laser brightness is enhanced further by raising the threshold of transverse mode instability by approximately 1.0 kW by coiling the gain fiber with a novel curvature shape. Finally, a 6 kW narrow-linewidth laser is achieved with beam quality (M2) of approximately 1.4. The laser brightness doubled compared to the results before optimization. To the best of our knowledge, it is the highest brightness narrow-linewidth fiber laser based on a one-stage master oscillator power amplification structure.
A dense particle suspension under shear may lose its uniform state to large local density and stress fluctuations, which challenge the mean-field description of the system. Here, we explore the novel dynamics of a non-Brownian suspension under orbital oscillations, where localized density waves along the flow direction appear beyond an excitation frequency threshold and self-organize into a hexagonal pattern across the system. The spontaneous occurrence of the inhomogeneity pattern arises from a coupling between particle advection and the shear-thickening nature of the suspension. Through linear stability analysis, we show that they overcome the stabilizing effects of particle pressure at sufficient particle volume fraction and oscillation frequency. In addition, the long-standing density waves degenerate into random fluctuations when replacing the free surface with rigid confinement. It indicates that the shear-thickened state is intrinsically heterogeneous, and the boundary conditions are crucial for developing local disturbance.
Bidirectional transformations (BXs) are a mechanism for maintaining consistency between multiple representations of related data. The lens framework, which usually constructs BXs from lens combinators, has become the mainstream approach to BX programming because of its modularity and correctness by construction. However, the involved bidirectional behaviors of lenses make the equational reasoning and optimization of them much harder than unidirectional programs. We propose a novel approach to deriving efficient lenses from clear specifications via program calculation, a correct-by-construction approach to reasoning about functional programs by algebraic laws. To support bidirectional program calculation, we propose contract lenses, which extend conventional lenses with a pair of predicates to enable safe and modular composition of partial lenses. We define several contract-lens combinators capturing common computation patterns including $\textit{fold}, \textit{filter},\textit{map}$, and $\textit{scan}$, and develop several bidirectional calculation laws to reason about and optimize contract lenses. We demonstrate the effectiveness of our new calculation framework based on contract lenses with nontrivial examples.
Maternal syphilis not only seriously affects the quality of life of pregnant women themselves but also may cause various adverse pregnancy outcomes (APOs). This study aimed to analyse the association between the related factors and APOs in maternal syphilis. 7,030 pregnant women infected with syphilis in Henan Province between January 2016 and December 2022 were selected as participants. Information on their demographic and clinical characteristics, treatment status, and pregnancy outcomes was collected. Multivariate logistic regression models and chi-squared automatic interaction detector (CHAID) decision tree models were used to analyse the factors associated with APOs. The multivariate logistic regression results showed that the syphilis infection history (OR = 1.207, 95% CI, 1.035–1.409), the occurrence of abnormality during pregnancy (OR = 5.001, 95% CI, 4.203–5.951), not receiving standard treatment (OR = 1.370, 95% CI, 1.095–1.716), not receiving any treatment (OR = 1.313, 95% CI, 1.105–1.559), and a titre ≥1:8 at diagnosis (OR = 1.350, 95%CI, 1.079–1.690) and before delivery (OR = 1.985, 95%CI, 1.463–2.694) were risk factors. A total of six influencing factors of APOs in syphilis-infected women were screened using the CHAID decision tree model. Integrated prevention measures such as early screening, scientific eugenics assessment, and standard syphilis treatment are of great significance in reducing the incidence of APOs for pregnant women infected with syphilis.
Aphids exhibit seasonally alternating asexual and sexual reproductive modes. Different morphs are produced throughout the life cycle. To evaluate morph-specific fitness during reproductive switching, holocyclic Sitobion avenae were induced continuously under short light conditions, and development and reproduction were compared in each morph. Seven morphs, including apterous and alate virginoparae, apterous and alate sexuparae, oviparae, males, and fundatrices, were produced during the life cycle. The greatest proportions of sexuparae, oviparae, males, and virginoparae were in the G1, G2, G3, and G4 generations, respectively. Regardless of asexual or sexual morphs, alate morphs exhibited a marked delay in age at maturity compared with that of apterous morphs. Among the alate morphs, males had the longest age at maturity, followed by sexuparae and virginoparae. Among the apterous morphs, sexuparae were older at maturity than the fundatrices, virginoparae, and oviparae. The nymphs of each morph had equal survival potentials. For the same wing morphs, apterous sexuparae and oviparae exhibited substantial delays in the pre-reproductive period and considerable reductions in fecundity, compared with those of apterous virginoparae and fundatrices, whereas alate sexuparae and alate virginoparae had similar fecundity. The seven morphs exhibited Deevey I survivorship throughout the life cycle. These results suggest that sexual production, particularly in males, has short-term development and reproduction costs. The coexistence of sexual and asexual morphs in sexuparae offspring may be regarded as an adaptive strategy for limiting the risk of low fitness in winter.
Many microorganisms use cilia to propel themselves in low Reynolds number ($Re$) environments. In this work, we study the dynamics of a composite cilium consisting of an elastic filament and a spherical particle attached at the filament tip driven by an external time-periodic force acting on the particle. The elastic filament is modelled numerically using a slender body theory with hydrodynamic interactions. When tilted at a large angle from the normal direction of the wall, the filament buckles, and the induced velocity field by the cilium shows a large net flux. By varying the tilt angle or the force amplitude, the particle trajectory and the net flux display abrupt changes along with a reversal of the buckling direction. We further demonstrate through a segmental model that the abrupt changes arise from the deviation of the cilium orientation at the start of the recovery stroke from the natural orientation. Our results suggest a simple approach to engineering particle motions and designing artificial cilia for fluid pumping in low $Re$ environments.
Menaquinone-7 (MK-7), a multipotent vitamin K2, possesses a wide range of biological activities, a precise curative effect and excellent safety. A simple and rapid LC-APCI-MS/MS method for the determination of MK-7 in human plasma with single liquid–liquid extraction (LLE) extraction and 4·5-min analysis time has been developed and validated. Four per cent bovine serum albumin (BSA) was used as surrogate matrix for standard curves and endogenous baseline subtraction. This method was reproducible and reliable and was used to analyse of MK-7 in human plasma. The endogenous circadian rhythm and bioavailability of MK-7 were investigated in two randomised single-dose, open, one-way clinical trials (Study I and Study II). A total of five healthy male subjects were enrolled in Study I and 12 healthy male subjects in Study II. Single-dose (1 mg) of MK-7 was given to each subject under fasting condition, and all eligible subjects were given a restricting VK2 diet for 4 d prior to drug administration and during the trial. The experiment results of Study I demonstrated that endogenous MK-7 has no circadian rhythm in individuals. Both studies showed MK-7 are absorbed with peak plasma concentrations at about 6 h after intake and has a very long half-life time.
We presented the first photometric and orbital period investigations for four W Ursae Majoris-type binaries: V473 And, V805 And, LQ Com, and EG CVn. The photometric solutions suggested that V805 And and LQ Com are two total-eclipse contact binaries, while V473 And and EG CVn are partial-eclipse ones. V473 And and LQ Com belong to the A-subtype contact binaries, while V805 And and EG CVn belong to the W subtype. The O’Connell effects found in the light curves of V805 And, LQ Com, and EG CVn can be interpreted as a result of a cool spot on the surface of their less massive and hotter primary components. Based on two different methods, the absolute physical parameters were properly determined. Combining the eclipse timings derived from our observations and survey’s data with those collected from literature, we investigated their orbital period variations. The results show that the orbital periods of V473 And, V805 And, and EG CVn are undergoing a secular decrease/increase superposed a periodic variation, while LQ Com exhibits a possible cyclic period variation with a small amplitude. The secular period changes are caused mainly by the mass transfer between two components, while the cyclic period oscillations may be interpreted as the results of either the light-time effect due to the third body or the cyclic magnetic activity. Finally, we made a statistical investigation for nearly 200 contact binaries with reliable physical parameters. The statistical results suggested that the W-subtype systems are more evolved than the A-subtype ones. Furthermore, the evolutionary direction of A-subtype into W-subtype systems is also discussed. The opposite evolutionary direction seems to be unlikely because it requires an increase of the total mass, the orbital angular momentum, and the temperature differences between two components of a binary system.
Accumulating evidence suggests that supplementation of n-3 PUFA was associated with reduction in risk of major cardiovascular events. This meta-analysis was to systematically evaluate whether daily supplementation and accumulated intake of n-3 PUFA are associated with improved left ventricular (LV) remodelling in patients with chronic heart failure (CHF). Articles were obtained from Pubmed, Clinical key and Web of Science from inception to January 1 in 2021, and a total of twelve trials involving 2162 participants were eligible for inclusion. The sources of study heterogeneity were explained by I2 statistic and subgroup analysis. Compared with placebo groups, n-3 PUFA supplementation improved LV ejection fraction (LVEF) (eleven trials, 2112 participants, weighted mean difference (WMD) = 2·52, 95 % CI 1·25, 3·80, I2 = 87·8 %) and decreased LV end systolic volume (five studies, 905 participants, WMD = –3·22, 95 % CI 3·67, −2·77, I2 = 0·0 %) using the continuous variables analysis. Notably, the high accumulated n-3 PUFA dosage groups (≥ 600 g) presented a prominent improvement in LVEF, while the low and middle accumulated dosage (≤ 300 and 300–600 g) showed no effects on LVEF. In addition, n-3 PUFA supplementation decreased the levels of pro-inflammatory mediators including TNF-α, IL-6 (IL-6) and hypersensitive c-reactive protein. Therefore, the present meta-analysis demonstrated that n-3 PUFA consumption was associated with a substantial improvement of LV function and remodelling in patients subjected to CHF. The accumulated dosage of n-3 PUFA intake is vital for its cardiac protective role.
The article aims to estimate and forecast the transmissibility of shigellosis and explore the association of meteorological factors with shigellosis. The mathematical model named Susceptible–Exposed–Symptomatic/Asymptomatic–Recovered–Water/Food (SEIARW) was used to explore the feature of shigellosis transmission based on the data of Wuhan City, China, from 2005 to 2017. The study applied effective reproduction number (Reff) to estimate the transmissibility. Daily meteorological data from 2008 to 2017 were used to determine Spearman's correlation with reported new cases and Reff. The SEIARW model fit the data well (χ2 = 0.00046, p > 0.999). The simulation results showed that the reservoir-to-person transmission of the shigellosis route has been interrupted. The Reff would be reduced to a transmission threshold of 1.00 (95% confidence interval (CI) 0.82–1.19) in 2035. Reducing the infectious period to 11.25 days would also decrease the value of Reff to 0.99. There was a significant correlation between new cases of shigellosis and atmospheric pressure, temperature, wind speed and sun hours per day. The correlation coefficients, although statistically significant, were very low (<0.3). In Wuhan, China, the main transmission pattern of shigellosis is person-to-person. Meteorological factors, especially daily atmospheric pressure and temperature, may influence the epidemic of shigellosis.
Under the national guidance of Internet Plus Healthcare, Internet hospital was officially recognized in 2018 by the Chinese government, however, how to innovate the business models of Internet hospitals remains controversial. This study sought to explore key stakeholders’ perspectives on key dilemmas about innovative business models of Internet hospitals in China.
Methods
A focus group study of key stakeholders was performed. Twelve key stakeholders (six senior officials from related ministries, two industry practitioners of Internet medicine, one hospital leader, two healthcare researchers (financing and policy), and one venture capital manager) participated in the focus group, in 2019. Thematic content analysis was applied for data analysis.
Results
Themes highlighted six key dilemmas when developing a business model of Internet hospitals, including (i) value proposition (medical treatment versus entire health management); (ii) leading party (hospitals versus third parties such as Internet companies); (iii) level of healthcare (tertiary versus primary); (iv) scope of service (provide full range versus part of traditional hospital service); (v) primary source of revenue (medical services versus drug sales); and (vi) legal liability (web-based unit versus physical hospital).
Conclusions
The healthcare industry is currently in search of innovative business models of Internet hospitals in response to the unprecedented form of healthcare in China. However, the core aspects of the model design still remain debatable. At this revolutionary stage, policies are important to allow the implementation of different model designs that support the successful transformation of the entire health care system in China.
This study aimed at estimating the transmissibility of hepatitis C. The data for hepatitis C cases were collected in six districts in Xiamen City, China from 2004 to 2018. A population-mixed susceptible-infectious-chronic-recovered (SICR) model was used to fit the data and the parameters of the model were calculated. The basic reproduction number (R0) and the number of newly transmitted cases by a primary case per month (MNI) were adopted to quantitatively assess the transmissibility of hepatitis C virus (HCV). Eleven curve estimation models were employed to predict the trends of R0 and MNI in the city. The SICR model fits the reported HCV data well (P < 0.01). The median R0 of each district in Xiamen is 0.4059. R0 follows the cubic model curve, the compound curve and the power function curve. The median MNI of each district in Xiamen is 0.0020. MNI follows the cubic model curve, the compound curve and the power function curve. The transmissibility of HCV follows a decreasing trend, which reveals that under the current policy for prevention and control, there would be a high feasibility to eliminate the transmission of HCV in the city.
In the laser plasma interaction of quantum electrodynamics (QED)-dominated regime, γ-rays are generated due to synchrotron radiation from high-energy electrons traveling in a strong background electromagnetic field. With the aid of 2D particle-in-cell code including QED physics, we investigate the preplasma effect on the γ-ray generation during the interaction between an ultraintense laser pulse and solid targets. We found that with the increasing preplasma scale length, the γ-ray emission is enhanced significantly and finally reaches a steady state. Meanwhile, the γ-ray beam becomes collimated. This shows that, in some cases, the preplasmas will be piled up acting as a plasma mirror in the underdense preplasma region, where the γ-rays are produced by the collision between the forward electrons and the reflected laser fields from the piled plasma. The piled plasma plays the same role as the usual reflection mirror made from a solid target. Thus, a single solid target with proper scale length preplasma can serve as a manufactural and robust γ-ray source.
The ablation and acceleration of diamond-like high-density carbon foils irradiated by thermal X-ray radiations are investigated with radiation hydrodynamics simulations. The time-dependent front of the ablation wave is given numerically for radiation temperatures in the range of 100–300 eV. The mass ablation rates and ablation pressures can be derived or implied from the coordinates of ablation fronts, which agree well with reported experiment results of high-density carbon with radiation temperatures Trad in the range of 160–260 eV. It is also found that the $T_{{\rm rad}}^3$ scaling law for ablation rates does not apply to Trad above 260 eV. The trajectories of targets and hydrodynamic efficiencies for different target thicknesses can be derived from the coordinates of ablation fronts using a rocket model and the results agree well with simulations. The peak hydrodynamic efficiencies of the acceleration process are investigated for different foil thicknesses and radiation temperatures. Higher radiation temperatures and target thicknesses result in higher hydrodynamic efficiencies. The simulation results are useful for the design of fusion capsules.