Sensitive Stage Research Articles

Crop Water Productivity and Crop Coefficients of Lentil (Lens Culinaris M.) Under Different Irrigation Regimes

This study was conducted for two consecutive winter seasons (2014/15 and 2015/16) at Hudeiba Research Station Farm to determine the effects of deficit irrigation imposed at different developmental stages and throughout the growing season on water use and water productivity of lentil (L. culinaris M.) and to derive the crop coefficient. Lentil Aribo cultivar wasgrown under six irrigation treatments in which one-irrigation was skipped at some of the growth stages, i.e. vegetative (W3), flowering (W4), pod setting (W5) and ripening stage (W6) and irrigation without skipping with intervalsof 10 days (full irrigation) (W1) and irrigation every 15 days (W2) (moderate water stress throughout the growing season). The experimental and/or high cost of irrigation water conditions, if only one irrigation is to be saved, the vegetative and ripening stages could be a safe option. design was randomized complete block design with three replications. Theaverage estimated values of crop coefficients during the initial, mid -season and late -season stages were 0.28, 1.06 and 0.48, respectively. The results revealed that the highest grain yield was recorded in full irrigation (1003 kgha-1) and significantly (p < 0.001) decreased by 13, 28 and 31% when deficit irrigation was applied throughout the growing season, at flowering and at pod setting stages, respectively. The highest and lowest values of crop waterproductivity resulted from deficit irrigation imposed at vegetative stage and at flowering stages, respectively. The most sensitive stages of lentil to water deficit were the flowering and pod setting. Therefore, under water shortage

Classification method of shale gas analytic stages and its application

China is rich in shale gas resources, and improving the oil recovery of shale gas wells is one of the hot issues in the current research. The production of shale gas wells releases shale gas by reducing formation pressure by repeated fracturing. In this paper, the curvature of shale desorption efficiency curve is analyzed to study the pressure suitable for formation shale gas release. According to the inflection point and stagnation point of the curvature curve, the starting pressure, sensitive pressure and turning pressure are obtained. the curvature curve can be divided into four stages: sensitive desorption, rapid desorption, slow desorption and inefficient desorption. In actual exploitation, shale desorption cannot go through all four desorption stages, and can be determined according to the ratio of V_{L} /P_{L}. When the ratio is greater than 2.59, there are four integral stages in shale desorption, and the larger the ratio is, the longer the sensitive desorption stage is. At 1.0–2.59, there are three stages of desorption; at 0.54–1, there are only two stages; below 0.54, there are only low efficiency stage. The isothermal adsorption study on the core samples of the Upper Paleozoic in Yulin area of Ordos Basin shows that the shale of the Upper Paleozoic in the study area has more starting pressure and turning pressure, and less sensitive pressure, and the ratio of V_{L} /P_{L} is between 0.5 and 2.0. Generally, the isotherm adsorption curve can be divided into three stages: fast desorption, slow desorption and low efficiency desorption. The low efficiency desorption stage contributes the most to the productivity of Upper Paleozoic shale in this area, and the slow desorption is supplementary. According to the desorption stage and pressure node in shale mining, the formation pressure can be appropriately reduced to improve shale gas recovery efficiency.

Stress Response of European Common Frog (Rana temporaria) Tadpoles to Bti Exposure in an Outdoor Pond Mesocosm

The biocide Bacillus thuringiensis var. israelensis (Bti) is applied to wetlands to control nuisance by mosquitoes. Amphibians inhabiting these wetlands can be exposed to Bti multiple times, potentially inducing oxidative stress in developing tadpoles. For biochemical stress responses, ambient water temperature plays a key role. Therefore, we exposed tadpoles of the European common frog (Rana temporaria) three times to field-relevant doses of Bti in outdoor floodplain pond mesocosms (FPM) under natural environmental conditions. We sampled tadpoles after each Bti application over the course of a 51-day experiment (April to June 2021) and investigated the activity of the glutathione-S-transferase (GST) and protein carbonyl content as a measure for detoxification activity and oxidative damage. GST activity increased over the course of the experiment likely due to a general increase of water temperature. We did not observe an effect of Bti on either of the investigated biomarkers under natural ambient temperatures. However, Bti-induced effects may be concealed by the generally low water temperatures in our FPMs, particularly at the first application in April, when we expected the highest effect on the most sensitive early stage tadpoles. In light of the global climate change, temperature-related effects of pesticides and biocides on tadpoles should be carefully monitored - in particular since they are known as one of the factors driving the worldwide decline of amphibian populations.

Rice yield penalty and quality deterioration is associated with failure of nitrogen uptake from regreening to panicle initiation stage under salinity.

In recent years, the development and utilization of saline land for rice cultivation have effectively expanded grain productivity. Rice is a salt-sensitive crop, and the increasing salinity problem threatens rice yield and quality. Therefore, we conducted open field experiments to study the effect of salinity on different growth stages of rice. Irrigating saline treatment was conducted at three different growth stages: irrigating saline from the regreening stage to the panicle initiation stage (S1), irrigating saline from the panicle initiation stage to the flowering stage (S2), and irrigating saline from the flowering stage to the maturity stage (S3). Each treatment period lasted for about 30 days. At the same time, irrigating saline water from the regreening stage to the maturity stage (S4) treatment was added in 2022 to explore the performance of salt stress during the whole growth period of rice. Based on the treatment of these different saline irrigation growth periods, three saline concentrations were incorporated, including salinity 0‰ (T1), 3‰ (T2), and 6‰ (T3) concentrations. No irrigating saline during the whole growth period was also used as a control (CK). The results indicated that rice grain yield and quality were most sensitive to saline treatment during S1 among the three stress periods. At the S1 stage, salinity mainly reduced the nitrogen uptake, resulting in stunted plant growth, reducing tillering, yield, and yield components, and deteriorating the rice quality. Compared to the control, IEN (grain yield over the total amount of N uptake in plants at maturity) was more sensitive at the S1 stage than S2 and S3 stages under salinity. Furthermore, the findings of our study suggest that under salinity, rice growth is not only directly affected by the higher sodium (Na+) content in plants, but the higher concentration of Na+ reduced the ability of plants to uptake nitrogen. Thus, more attention should be paid to the field management of the S1 stage, the most sensitive stage during rice cultivation in salinized areas. It is necessary to avoid salt damage to rice during this period and ensure irrigation with precious freshwater resources.

Impacts of heat shock on productivity and quality of Triticum aestivum L. at different growth stages

The transitional phase of climate change is becoming a threat worldwide. Fluctuations in temperature are frequently observed in the life cycles of field crops. The current study was intended to evaluate heat stress (HS) at sensitive stages on four wheat cultivars’ growth, grain yield, and quality traits during two consecutive seasons. The experiment included four spring wheat cultivars that were exposed to HS durations (i.e., 0, 48, 96 and 144 h) at booting and anthesis stages. Pots were kept in an open-air, and labeled pots were moved to the glasshouse at the respective growth stage. After HS treatments, pots were moved from the glasshouse to the original position in the open air. The results showed that the cultivars differed in yield and grain quality traits, but their collective mean effect was significantly expressed with HS and HS duration (HSd) on the measured traits. Spike length was significantly affected by HS at the anthesis in comparison to those obtained from the control. However, the increase in HSd did not cause a significant effect on spike length compared to other treatments. Spike weight was significantly decreased in plants exposed to HS at booting and anthesis as well as by increasing HSd. In addition, grain weight and numbers were decreased in plants exposed to HS at booting and anthesis stages with a similar pattern by increasing HSd. Moreover, a reduction in amylose content was observed in grains of plants exposed to HS at booting and anthesis stages or when plants as exposed to a longer period of HSd. Nonetheless, amylopectin, wet gluten (WG) and grain N (GN) showed an increase in plants exposed to HS at booting and anthesis stages and/or extending HSd. This study concludes that plants exposed to different HS treatments during the life cycle had lower values for spike length, grains weight, and grains number per spike including amylose content in comparison to those obtained from the control. The decrease was significantly noted in the yield and grain quality of wheat when plants were exposed to HS at the booting stage in comparison to those exposed to HS at anthesis.

High sensitivity to dietary imidacloprid exposure in early life stages of Folsomia quadrioculata (Collembola) populations from contrasting climates

Survival of early life stages is critical for population growth. Understanding the vulnerability of these sensitive stages can therefore improve ecological risk predictions. The globally-used neonicotinoid insecticide imidacloprid does not degrade easily in soil and occurs at concentrations potentially toxic to non-target soil organisms, such as Collembola. Here, we studied the effects of dietary exposure to imidacloprid on the survival of juveniles in an arctic and a temperate population of Folsomia quadrioculata (Collembola), a commonly-occurring litter-dwelling species in the Northern Hemisphere. The exposure lasted from <24 h to 30 days since hatching at 15 °C. We assessed whether (1) the arctic population of the test species with faster development rates could be more vulnerable than the temperate population, (2) cumulative mortality could increase substantially with exposure time, and (3) the mortality risk experienced during the juvenile stage could be greater than that experienced by the adults. We found a strong concentration-dependent decline in survival in both populations, with small but significantly different LC50s, despite large differences in multiple life-history traits. Applying a General Unified Threshold model for Survival (GUTS) showed a low threshold for effects, slow damage dynamics, a 6–11-fold decrease in LC50 from 14 to 30 days of exposure, and saturation of damage at the three highest concentrations. In addition, exposure starting soon after hatching caused much more mortality than that starting in the adult stages. Our findings suggest that toxicity tests not emphasizing the neonate stages or not lasting long enough can underestimate the implications for populations of naturally abundant non-target organisms.

Invited Perspective: PFAS in Breast Milk and Infant Formula-It's Time to Start Monitoring.

Invited Perspective: PFAS in Breast Milk and Infant Formula-It's Time to Start Monitoring.

Critical reflection to develop transformative consciousness of racial differences

ABSTRACT Aspiring educational leaders must understand their own culture and the cultures of others to lead schools effectively and realise equitable outcomes for traditionally marginalised students. To explore the potential for professional learning to affect students’ frames of reference regarding cultural interactions, we analysed self-reflection papers from graduate students within an educational leadership preparation programme at a US public university. We investigated sociocultural distortions of race and ethnicity when students reflected on their first-hand (direct contact and conversations) and second-hand (news reports and stories) encounters with people who are phenotypically different from themselves. The course included readings, discourse, and reflective journaling about racial interactions. We utilised Mezirow’s theory of transformative learning to understand how students developed self-awareness and progressed through stages of intercultural competence and sensitivity. Most participants progressed through developmental stages of intercultural sensitivity, and many moved from ethnocentric to ethnorelative stances. Findings indicate the importance of purposely designing learning experiences that allow aspiring leaders to critically self-reflect on topics of race and equity prior to assuming formal leadership positions.

Behavioral-play familiarization for non-sedated magnetic resonance imaging in young children with mild traumatic brain injury.

Mild traumatic brain injury (mTBI) sustained in early childhood affects the brain at a peak developmental period and may disrupt sensitive stages of skill acquisition, thereby compromising child functioning. However, due to the challenges of collecting non-sedated neuroimaging data in young children, the consequences of mTBI on young children's brains have not been systematically studied. In typically developing preschool children (of age 3-5years), a brief behavioral-play familiarization provides an effective alternative to sedation for acquiring awake magnetic resonance imaging (MRI) in a time- and resource-efficient manner. To date, no study has applied such an approach for acquiring non-sedated MRI in preschool children with mTBI who may present with additional MRI acquisition challenges such as agitation or anxiety. The present study aimed to compare the effectiveness of a brief behavioral-play familiarization for acquiring non-sedated MRI for research purposes between young children with and without mTBI, and to identify factors associated with successful MRI acquisition. Preschool children with mTBI (n=13) and typically developing children (n=24) underwent a 15-minutes behavioral-play MRI familiarization followed by a 35-minutes non-sedated MRI protocol. Success rate was compared between groups, MRI quality was assessed quantitatively, and factors predicting success were documented. Among the 37 participants, 15 typically developing children (63%) and 10 mTBI (77%) reached the MRI acquisition success criteria (i.e., completing the two first sequences). The success rate was not significantly different between groups (p=.48; 95% CI [-0.36 14.08]; Cramer's V=.15). The images acquired were of high-quality in 100% (for both groups) of the structural images, and 60% (for both groups) of the diffusion images. Factors associated with success included older child age (Β=0.73, p=.007, exp(B)=3.11, 95% CI [1.36 7.08]) and fewer parental concerns (Β=-1.56, p=.02, exp(Β)=0.21, 95% CI [0.05 0.82]) about the MRI procedure. Using brief behavioral-play familiarization allows acquisition of high-quality non-sedated MRI in young children with mTBI with success rates comparable to those of non-injured peers.

Chemical hazard of robotic hull in-water cleaning discharge on coastal embryonic fish

In-water cleaning (IWC) involves the removal of biofilms and foulants from the hull of a ship using brush or water jet. During IWC, several factors associated with the harmful chemical contaminants release to the marine environment, which can create “hotspots” of chemical contamination in coastal areas. To elucidate the potential toxic effects of IWC discharge, we investigated developmental toxicity in embryonic flounder, which are sensitive life stage to chemical exposure. Zinc and copper were the dominant metals, while zinc pyrithione was the most abundant biocide associated with IWC discharge in two remotely operated IWC. Discharge from IWC carried by both remotely operated vehicles (ROVs) produced developmental malformations including pericardial edema, spinal curvature, and tail-fin defects. In an analyses of differential gene expression profiles (fold-change of genes with a cutoff < 0.05) as assessed by high-throughput RNA sequencing, genes associated with muscle development were commonly and significantly changed. The gene ontology (GO) of embryos exposed to IWC discharge from ROV A activities highly enriched muscle and heart development, while cell signaling and transport were evident in embryos exposed to IWC discharge of ROV B. We analyzed the gene network by significant GO terms. In the network, TTN, MYOM1, CASP3, and CDH2 genes appeared to be key regulators of the toxic effects on muscle development. In embryos exposed to ROV B discharge, HSPG2, VEGFA, and TNF genes related to the nervous system pathway were affected. These results shed light on the potential impacts of muscle and nervous system development in non-target coastal organisms exposed to contaminants found in IWC discharge.

Unclonable fluorescence of MgO-ZrO2 :Tb3+ nanocomposite for versatile applications in data security, dermatoglyphics.

Latent fingerprints (LFPs) are one among the most important types of evidences at crime scenes because of the distinctiveness and tenacity of the friction ridges in fingerprints (FPs). Therefore, it is essential in forensic science to develop a reliable method to detect LFPs. Traditional detection methods still face a number of difficulties, such as limited sensitivity, low contrast, strong background, and complex processing stages. In this study, MgO-ZrO2 :Tb3+ (1-5mol%) (MZ:Tb) nanocomposites (NCs) were prepared via a simple solution combustion (SC) method at low temperature. The photoluminescence (PL) investigation demonstrates that when excited at 379 nm, the produced NCs emits distinctive emission peaks of terbium ions (Tb3+ ). According to the photometric results, the NCs can be employed as warm light NCs and emit light in the green portion of the colour spectrum. The estimated optical band gap from diffuse reflectance spectra is found to be in the range 4.84-4.97 eV. Regardless of the type of surface being used, the optimized MgO-ZrO2 :Tb3+ (4mol%) (MZ:4Tb) NCs has a strong ability to minimize background fluorescence interference. With high contrast LFP and I-V type of cheiloscopy, these NCs present a flexible fluorescent mark for the identification of levels 1-3 details in forensic investigation.

MANAGEMENT OF INSECT PEST IN RICE SEEDBED USING A NOVEL RECTANGULAR HAND NET (RHN) FOR INSECTICIDE FREE SEEDLINGS

Insect pest first attacks rice in seedbed generally 7-9 days after sprouted seed sowing. At this early sensitive stage, traditional sweep net (round hand net) is not suitable to collect insects because it injured tender rice seedlings and its insect catching efficiency is also lower than rectangular hand net. To alleviate this problem, developed a novel rectangular hand net and evaluated the efficacy for managing insect pest in rice seedbeds. Newly developed hand net consists of a rectangular frame that includes 4 mm GI wire, and the frame length and width 50 cm and 20 cm, respectively. It also consists of a plastic pipe that length 100 cm, radious 0.75 inch, and market available white colour mosquito net, which length from the frame is 80 cm. Methods of application is rapidly walking with RHN (Fig. 2) around the seedbed (model seedbed one-meter width and length depends on land condition). After sweeping full seedbed harmful insect has been destroyed and beneficial insect released back in the same field. RHN caught maximum number of major populations YSB, rice hispa, BPH, rice leaf folder, GH, etc., and remained under control. RHN caught beneficial insect (19.60 %) compare to harmful insect pest (80.39 %). In Aus season 2022, 20 m2 area BRRI dhan48, BRRI dhan98, BRRI dhan85 seedbed tenure caught insect pest (87.78 %) and natural enemy (12.22 %). Same year T. Aman season BRRI dhan76 and BRRI dhan52 seedbed period insect pest caught (71.18%) and natural enemy (28.82 %). Both seasons conducted this experiment at BRRI, Barishal Charbadna and Sagordi farm.

Selenium Application Improves Drought Tolerance during Reproductive Phase of Rice

Rice (Oryza sativa L.) grain yield is reduced by drought stress during reproductive stages. In this work, the effects of foliar selenium (Se) spray on the reduction of drought stress are measured and the most critical stage of rice is identified. Three field experiments were carried out. In experiments I and II, the sensitive stage was determined by imposing drought stress at the panicle initiation and flowering stages by withholding irrigation for 10, 15, 20, and 25 days. In experiment III, drought stress was induced by depriving plants of moisture for 20 or 25 days. Se spray was then applied at rates of 0, 10, and 20 mg L−1 to alleviate the drought, and its effects were evaluated. Overall, it was reported that the panicle initiation stage was more vulnerable to drought stress than the flowering stage, as evidenced by a larger reduction in grain yield. Employing Se as a foliar spray at a rate of 20 mg L−1 under drought stress enhanced the number of filled grains m−2, the total number of grains m−2, and grain yield ha−1 by 22.0, 4.3, and 11.0%, respectively, over water spray. This shows a positive interaction or synergistic interaction between drought tolerance and selenium application. These results demonstrate that foliage supplementation of Se at a dosage of 20 mg L−1 alleviate the adverse effects of drought stress at the panicle initiation stage in rice cultivation. Se mitigated the negative effects of drought by improving the membrane stability index, relative water content, and proline content.

Toxicity risks associated with trace metals call for conservation of threatened fish species in heavily sediment-laden Yellow River

Trace metals and metalloids in aquatic ecosystems may lead to adverse effects on the survival of fish, especially in the sensitive life stages of vulnerable species. It is still unknown whether threatened fish species in the heavily sediment-laden Yellow River are exposed to toxicity risks associated with multiple trace metals. Herein, we analyzed the concentrations of trace metals in aquatic environmental media and fish tissues across the Yellow River mainstream and assessed the level of metal toxicity to threatened fish. Significantly different concentrations of trace metals in fish tissues were measured between at least two categories among near-threatened, vulnerable, endangered, and critically endangered fish. No metal showed a higher concentration in demersal fish than in pelagic fish. Substantially low metal toxicity was observed for the gill of Rhinogobio nasutus (near-threatened) in the upper reaches, as well as for the gill and liver of Silurus lanzhouensis (endangered) in the middle reaches. High contents of suspended sediment in water and high metal concentrations in sediment and suspended matter could influence the survival and reproduction of fish, especially those already with threatened status.

Foliar application of potassium and restricted irrigation improved the growth and yield of wheat under rainfed condition of Bhal region

Foliar application of potassium increases the drought tolerance in the wheat crop with restricted irrigation, keeping in the view, a field experiment effect of foliar K application for improving wheat yield and water productivity under restricted irrigation condition was conducted at Agricultural Research station, Anand Agricultural University, Dhandhuka, Bhal region of Gujarat under conserved soil moisture condition with restricted irrigation in the Rabi season of 2021-22 with the objective to reduce moisture stress and to enhance the yield potential of wheat by using potash sprays. Inadequate moisture during the sensitive stages will cause substantial reduction in yield. The experiment was laid out in three replication with nine treatments in split plot design. They are (A). Irrigation levels, I1­: One irrigation at CRI stage, I2: Two Irrigation at CRI and flowering stage, I3: Three irrigation at CRI, late jointing and milking stage. (B). Foliar K application, F1: Control (Water spray), F2: 2% K foliar application at tillering (40-45) and jointing (60-65 DAS), and K3: 4% K foliar application at tillering (40-45) and jointing. The result indicated that due to irrigation management plant height at harvest (70.56 cm), length of ear (7.12), biological yield (7751 kg/ha) and grain yield (3367 kg/ha) was found significant with I3 treatment rest of parameters found non- significant with irrigation levels. Further data indicate from K foliar application, the plant height at harvest (71.51 cm), no of ear head sq. m. (295.44), length of ear (7.17), no, of grain per ear (32.68), test weight (44.03), biological yield (7112 kg/ha) and grain yield (3244 kg/ha) were recorded superior with K3 Treatment (4% K foliar application at tillering (40-45) and jointing) whereas, plant height, no of ear head (sq. m) no, of grain per ear, biological yield and grain yield found at par with F2 treatments Overall, it was observed that the foliar potassium fertilization and restricted irrigation increased the growth, yield attributes and grain yield.

Natural and synthetic microfibers alter growth and behavior in early life stages of estuarine organisms

Increasing shares of microfibers are being detected in environmental samples and a closer look to identify the risk associated with them using ecologically relevant endpoints, especially at sensitive early life stages, is needed. To assess exposure hazards, we used rope samples representative of fiber types ubiquitous in coastal systems, where microfibers are often the most common debris type found in the water column. To compare responses to natural vs. synthetic microfibers, we used rinsed “natural” cotton, polyester, and polypropylene microfibers (80-150 µm length, 8-20 µm width) created from the rope. Larval and juvenile estuarine indicator species Inland Silverside (Menidia beryllina) and mysid shrimp (Americamysis bahia), respectively, were exposed to these three microfiber types at three concentrations (3, 10, 30 particles/ml) along a 5-25 PSU salinity gradient to mimic estuarine conditions. Behavioral responses, growth, and ingestion were measured. The cotton microfibers were not detected in the digestive tracts of Silversides, however, both the polyester and polypropylene microfibers were detected in the Silversides’ stomach and gut lining. None of the fiber types were detected in mysid shrimps. Mysids exposed to cotton microfibers had fewer behavioral effects compared to Silversides, who responded more to cotton. Cotton exerted no effect on growth in Silversides but did cause reduced growth in the mysids at the two lower salinities. In contrast, polyester and polypropylene were identified to have a significant dose dependent effect on mysid and Silverside behavior as well as growth was affected in at least one of the three salinities at concentrations as low as 3 particles/ml. Cotton impacted both the organism’s behavior more at higher salinities, whereas polyester and polypropylene had more impacts at lower salinities. This raises concerns for microfiber impacts on estuarine ecosystems and the need for policies to limit microfiber production and outfall into the aquatic environment.

The Frequency of Pregnancy Complaints and the Effective Socio-demographic Factors Among Pregnant Women Referring to Neyshabur Health Centers in 2021

Background: Pregnancy is one of the most sensitive stages of a woman's life, and changes at this time can have physical and psychological complications for women. Objectives: This study aimed to assess the frequency of pregnancy complaints (PC) and the effective socio-demographic factors among pregnant women referred to Neyshabur health centers. Methods: This cross-sectional study was performed on 417 pregnant women referred to Neyshabur health centers in 2021. Data collection was carried out using demographic characteristics and PC questionnaires. Descriptive statistics (mean, standard deviation), analytical statistics (multiple linear regression). The software used for data analysis was SPSS software version 22. The significance level was considered at 0.05. Results: The mean age of pregnant women was 28.36 ± 5.96. The mean PC score was 37.76 ± 8.85. Fatigue (73.38%) and hemorrhoids (4.8%) were the most common and least common PC. Multiple linear regression results showed that maternal age (P &lt; 0.05) and sleep quality (P &lt; 0.001) were statistically significant variables related to PC. On this basis, as maternal age increases, the mean score for PC increases by 0.94. In addition, the average score of pregnancy-related complaints for those with a good sleep quality was 6.32 lower than for those with a bad sleep quality. Conclusions: Maternal age and bad sleep quality factors increase the possibility of a pregnancy-related complaint. So, it is recommended that healthcare providers develop and implement educational interventions to improve sleep quality and pregnancy awareness at older ages.

Digital Ethnic Enclaves: Mate Preferences and Platform Choices Among Chinese Immigrant Online Daters in Vancouver

In light of the growing racialized immigrant population in Canada and advances in dating technologies, this study examines Chinese immigrants' partner preferences and mate selection processes through the lens of online dating. We draw on in-depth interviews with 31 Chinese immigrants who have used online dating services in Metro Vancouver to search for different-sex partners. Chinese immigrant online daters show strong preferences for dating Chinese. They emphasize permanent residency status and similarity in age at arrival when evaluating potential partners. Given their preferences, Chinese immigrants strategically choose the dating platforms they primarily use. Men exhibit higher selectivity in their preferences and choices of platforms. Notably, platforms catering to Chinese users create "digital ethnic enclaves" where Chinese immigrant daters congregate. The findings illuminate the intersection of race, gender, immigrant status, and age at arrival in shaping divergent experiences of mate selection and immigrant assimilation in the digital era.

Next-generation PFAS 6:2 fluorotelomer sulfonate reduces plaque formation in exposed white-footed mice.

6:2 fluorotelomer sulfonate (6:2 FTS) has been used as a replacement for legacy per- and polyfluoroalkyl substances (PFAS). We assessed reproductive and developmental effects in a human-wildlife hybrid animal model based on the association of adverse effects linked to legacy PFAS with these sensitive life stages. In this study, white-footed mice were exposed orally to 0, 0.2, 1, 5, or 25 mg/kg-day 6:2 FTS for 112 days (4 weeks premating exposure plus at least 4 weeks mating exposure). Pregnancy and fertility indices were calculated, and litter production, total litter size, live litter size, stillbirths, litter loss, average pup weight, and pinna unfolding were assessed. Sex steroid and thyroid hormone serum levels were assessed. Body weight, histopathology, and immune function were also assessed in this study. Reproductive endpoints were not significantly altered in response to 6:2 FTS. Spleen weight increased in male mice dosed with 6:2 FTS. Immune function determined via a plaque-forming cell (PFC) assay was decreased in both male and female mice in the 2 highest doses. A low benchmark dose was calculated based on PFCs as the critical effect and was found to be 2.63 and 2.26 mg/kg-day 6:2 FTS in male and female mice, respectively. This study characterizes 6:2 FTS as being potentially immunotoxic with little evidence of effect on reproduction and development; furthermore, it models acceptable levels of exposure. These 2 pieces of information together will aid regulators in setting environmental exposure limits for this PFAS currently thought to be less toxic than other PFAS.

Field screening for heat-stress tolerance of floret fertility in wheat (Triticum aestivum and T. durum)

Context As global temperatures increase, heat waves of &gt;30°C for at least 3 days are projected to become more frequent during reproductive development of wheat, causing reductions in grain yield. Breeding for tolerance is difficult under field conditions owing to the unpredictable timing and intensity of natural heat events and the narrow developmental windows of sensitivity. Aims We report on a series of experiments designed to explore genetic variability for floret sterility induced by natural heat waves in the field by targeting a sensitive development stage. Methods Our method involved sowing late, and the use of auricle distance to identify main tillers exposed to heat events at a sensitive developmental stage (booting). Key results Substantial genetic variation was found for tolerance of grain set to natural heat waves, with a broad-sense heritability estimate of 0.94 for heat-exposed stems compared with 0.72 for non-stressed controls. An auricle distance of 1–3 cm was established as a phenotypic marker for tagging stems at the sensitive stage of development, and the optimal number of spikes to assess was determined as 10–15 per plot. A validation study with durum lines previously classified as tolerant/intolerant under glasshouse conditions showed agreement in ranking of genotypes at the extremes of tolerance. Conclusions We demonstrate that it is possible to screen wheat genotypes for stage-specific tolerance to natural heat waves in the field. Implications The protocol described could provide a low-cost method for evaluating heat tolerance in wheat, with relevance to commercial field production conditions. The approach allows tolerance to be assessed at a single stage of reproductive development, which should allow greater heritability in field assessments.