Development of an Imaging Spectrometer with a High Signal-to-Noise Ratio Based on High Energy Transmission Efficiency for Soil Organic Matter Detection.

Hyperspectral detection of the change rate of organic matter content in agricultural remote sensing requires a high signal-to-noise ratio (SNR). However, due to the large number and efficiency limitation of the components, it is difficult to improve the SNR. This study uses high-efficiency convex grating with a diffraction efficiency exceeding 50% across the 360-850 nm range, a back-illuminated Complementary Metal Oxide Semiconductor (CMOS) detector with a 95% efficiency in peak wavelength, and silver-coated mirrors to develop an imaging spectrometer for detecting soil organic matter (SOM). The designed system meets the spectral resolution of 10 nm in the 360-850 nm range and achieves a swath of 100 km and a spatial resolution of 100 m at an orbital height of 648.2 km. This study also uses the basic structure of Offner with fewer components in the design and sets the mirrors of the Offner structure to have the same sphere, which can achieve the rapid adjustment of the co-standard. This study performs a theoretical analysis of the developed Offner imaging spectrometer based on the classical Rowland circular structure, with a 21.8 mm slit length; simulates its capacity for suppressing the +2nd-order diffraction stray light with the filter; and analyzes the imaging quality after meeting the tolerance requirements, which is combined with the surface shape characteristics of the high-efficiency grating. After this test, the grating has a diffraction efficiency above 50%, and the silver-coated mirrors have a reflection value above 95% on average. Finally, the laboratory tests show that the SNR over the waveband exceeds 300 and reaches 800 at 550 nm, which is higher than some current instruments in orbit for soil observation. The proposed imaging spectrometer has a spectral resolution of 10 nm, and its modulation transfer function (MTF) is greater than 0.23 at the Nyquist frequency, making it suitable for remote sensing observation of SOM change rate. The manufacture of such a high-efficiency broadband grating and the development of the proposed instrument with high energy transmission efficiency can provide a feasible technical solution for observing faint targets with a high SNR.

Characteristics and contraceptive practices among Chinese women seeking abortion: a multicentre, descriptive study from 2019 to 2021.

INTRODUCTION: Despite the widespread provision of free contraceptives and post-abortion care (PAC) services, China grapples with a high rate of unintended pregnancies and subsequent abortions. We aimed to study the evolving characteristics of women seeking abortion and their contraceptive practices before and after abortions, to shed light on the optimisation of Chinese PAC services. METHODS: This study utilised data from an abortion cohort between 2019 and 2021. We studied their demographic features, contraception and abortion histories, reasons and choices using chi-square or linear-by-linear tests. We also explored the potential impact of receiving services at PAC facilities on post-abortion contraception use and repeat abortions using logistic regression models. RESULTS: Among the 9005 participants, 43.4% experienced repeat abortion, without a discernible trend over the 3 years. Noteworthy increases were observed in the percentages of college students (from 1.7% to 6.6%, p<0.01) and middle-aged women (from 23.2% to 26.8%, p<0.01) seeking abortions. Surgical abortion was chosen by nearly 90% of participants with a continuously increasing trend (p trend <0.01). Nearly half of the participants experienced unintended pregnancies due to non-use of contraception. Of the remainder, the majority preferred less or the least effective methods both before and after abortion. Women residing in moderate-gross domestic product (GDP) regions faced a higher risk of repeat abortions (OR 1.33, 95% CI 1.16 to 1.54). Despite this, high-quality PAC services may encourage the use of reliable contraceptive methods, with 86.8% of women changing from least effective or no methods to (most) effective methods post-abortion, and prevent repeat abortions (OR 0.65, 95% CI 0.56 to 0.75). CONCLUSIONS: Increased proportions of college students and middle-aged multiparous women seeking abortions were observed, together with inappropriate preferences for less effective contraception and increasing choice of surgical abortions. Future research should extend the focus to cover the entire abortion period, advocate the rational selection of contraceptive methods, and emphasise the specified PAC services tailored to different socioeconomic groups.

Strategies for Improving Postpartum Contraception Compared With Routine Maternal Care: A Systematic Review and Meta-Analysis.

Objectives: This study aimed to systematically review the effectiveness of service interventions for improving postpartum contraception, including contraceptive use, prevention of repeat pregnancies and induced abortions. Methods: A systematic literature search was conducted in three databases until June 2022 (PROSPERO registration CRD42022328349). Estimates of intervention effects from meta-analyses were represented as odds ratios (OR) with 95% confidence intervals (CI). Results: 16 studies with 14,289 participants were included, with four kinds of interventions recognized. Interventions effect in increasing use of contraceptives and decreasing rates of repeated pregnancy for up to 6 months postpartum (OR = 2.24, 0.06, 95% CI = 1.46-3.44, 0.02-0.22, respectively), with no significant associations with contraceptive use at 12 months postpartum, prevention of postpartum repeat pregnancies and induced abortions during 1 year after childbirth. Conclusion: We concluded that interventions impact the initiation of postpartum contraceptive use and prevention of repeat pregnancy with an overall certainty from low to moderate. These findings highlight the need for additional studies to integrate the beneficial effect of several interventions and then design more feasible strategies, which is important for the maternal and child healthcare systems.

Freeform reflector light source used for space traceable spectral radiance calibration on the solar reflected band.

For purpose of improving the accuracy of in-orbit radiometric calibration of Chinese Space-based Radiometric Benchmark (CSRB) reference payload on the reflected solar band and reduce resource consumption, this paper proposed a freeform reflector radiometric calibration light source system based on the beam shaping characteristics of the freeform surface. The design method of initial structure discretization based on Chebyshev points was used to design and solve the freeform surface, and the feasibility of the design method was verified by optical simulation. The designed freeform surface is machined and tested, and the test results show that the surface roughness root mean square (RMS) of the freeform reflector is 0.61 µm, which indicates that the continuity of the machined surface is good. The optical characteristics of the calibration light source system are measured, the results show that the irradiance uniformity and radiance uniformity are better than 98% in the effective illumination area of 100 mm × 100 mm on the target plane. The constructed freeform reflector calibration light source system can meet the requirements of large area, high uniformity and light weight for onboard calibration of the payload of the radiometric benchmark, improving the measurement accuracy of spectral radiance on the reflected solar band.

Stage-Specific Genetic Interaction between FgYCK1 and FgBNI4 during Vegetative Growth and Conidiation in Fusarium graminearum.

CK1 casein kinases are well conserved in filamentous fungi. However, their functions are not well characterized in plant pathogens. In Fusarium graminearum, deletion of FgYCK1 caused severe growth defects and loss of conidiation, fertility, and pathogenicity. Interestingly, the Fgyck1 mutant was not stable and often produced fast-growing spontaneous suppressors. Suppressor mutations were frequently identified in the FgBNI4 gene by sequencing analyses. Deletion of the entire FgBNI4 or disruptions of its conserved C-terminal region could suppress the defects of Fgyck1 in hyphal growth and conidiation, indicating the genetic relationship between FgYCK1 and FgBNI4. Furthermore, the Fgyck1 mutant showed defects in polarized growth, cell wall integrity, internalization of FgRho1 and vacuole fusion, which were all partially suppressed by deletion of FgBNI4. Overall, our results indicate a stage-specific functional relationship between FgYCK1 and FgBNI4, possibly via FgRho1 signaling for regulating polarized hyphal growth and cell wall integrity.

How Parenting and Family Characteristics Predict the Use of Feeding Practices among Parents of Preschoolers: A Cross-Sectional Study in Beijing, China.

Parental coercive and structured feeding practices are linked with children's weight gain. Thus, identifying their predictors will assist in childhood obesity prevention. We explored how parents' concerns and perceptions of children's weight, parenting stress, parenting competence, parents' family roles, and only child status (of both parent and child) predict the use of restriction, pressure to eat, and monitoring practices among parents of preschoolers. Parent-child dyads (n = 2990) were recruited in Beijing in 2019. Parenting competence, parents' weight perceptions and feeding practices were assessed using the Chinese version of Parenting Sense of Competence Scale and Child Feeding Questionnaire (CFQ), respectively. Parenting stress and other variables were collected through self-administered questionnaires. Multivariate linear associations between parents' weight perceptions and feeding practices were significant among normal-weight children. Parents' concerns about children being overweight were positively associated with restriction and monitoring, and negatively associated with pressure to eat. Higher levels of parenting stress and parenting competence significantly improved the adoption of restriction and pressure to eat. Parents' only child status and that of children had an impact on parents' feeding practices. The fathers' feeding preferences were substantially different from what mothers preferred. In conclusion, such parenting and family characteristics significantly influenced feeding practices of preschoolers' parents. These were long neglected in China.

Impact of Obesogenic Environments on Sugar-Sweetened Beverage Consumption among Preschoolers: Findings from a Cross-Sectional Survey in Beijing.

The excessive consumption of sugar-sweetened beverages (SSBs) has been proven to be critical for obesity among preschoolers. This study aimed to describe the SSB consumption rates among preschoolers in the Dongcheng District of Beijing, China, and to explore the association between obesogenic environmental determinants and consumption. We applied a stratified cluster sampling method and recruited 3057 primary caregivers of preschoolers in June 2019 to participate in the survey. The caregivers reported their children's consumption rates of six categories of SSBs and their exposure rates to SSB-related obesogenic environments. The associations between them were tested using multivariate logistic regression models. The mean (SD) age of the children was 5.6 (0.6) years and nearly half (48.3%) were girls. About 84.5% of the children had consumed SSBs over the past three months, and sugar-sweetened milk beverages had the highest consumption rate. Higher exposure to advertisements for the corresponding SSB categories in children, higher frequency rates of consuming SSBs and of taking children to fast-food restaurants in caregivers, and lower frequency rates of reading the Nutrition Facts Panels by caregivers were associated with higher SSB consumption rates among children (p < 0.05 in all of the SSB categories investigated, except for the Nutrition Facts Panel reading behaviors for the sports and energy beverages). SSB consumption among preschoolers is of concern, and comprehensive policy actions and education are urgently needed.

Viral Characteristics of the Warm Atlantic and Cold Arctic Water Masses in the Nordic Seas.

Nordic Seas are the subarctic seas connecting the Arctic Ocean and North Atlantic Ocean with complex water masses, experiencing an abrupt climate change. Though knowledge of the marine virosphere has expanded rapidly, the diversity of viruses and their relationships with host cells and water masses in the Nordic Seas remain to be fully revealed. Here, we establish the Nordic Sea DNA virome (NSV) data set of 55,315 viral contigs including 1,478 unique viral populations from seven stations influenced by both the warm Atlantic and cold Arctic water masses. Caudovirales dominated in the seven NSVs, especially in the warm Atlantic waters. The major giant nucleocytoplasmic large DNA viruses (NCLDVs) contributed a significant proportion of the classified viral contigs in the NSVs (32.2%), especially in the cold Arctic waters (44.9%). The distribution patterns of Caudovirales and NCLDVs were a reflection of the community structure of their hosts in the corresponding water masses and currents. Latitude, pH, and flow speed were found to be key factors influencing the microbial communities and coinfluencing the variation of viral communities. Network analysis illustrated the tight coupling between the variation of viral communities and microbial communities in the Nordic Seas. This study suggests a probable linkage between viromes, host cells, and surface water masses from both the cool Arctic and warm Atlantic Oceans. IMPORTANCE This is a systematic study of Nordic Sea viromes using metagenomic analysis. The viral diversity, community structure, and their relationships with host cells and the complex water masses from both the cool Arctic and the warm Atlantic oceans were illustrated. The NCLDVs and Caudovirales are proposed as the viral characteristics of the cold Arctic and warm Atlantic waters, respectively. This study provides an important background for the viromes in the subarctic seas connecting the Arctic Ocean and North Atlantic Ocean and sheds light on their responses to abrupt climate change in the future.