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Abstract Background Progressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation. However, studies on the effects of processive oxidative stress on nutrient transport in the placenta have received little attention. The present study was conducted on sows at 85 days of gestation to study the effects of pterostilbene (PTE) on maternal oxidative stress status and placental nutrient transport. Results PTE increased the antioxidant capacity and immunoglobulin content in mothers’ blood and milk, reduced the level of inflammatory factors, and improved the nutrient content of milk. PTE also reduced sow backfat loss and the number of weak sons, and increased piglet weaning weight and total weaning litter weight. We subsequently found that PTE enhanced placental glucose and fatty acid transport and further affected glycolipid metabolism by increasing the expression of LAL, PYGM, and Gbe-1, which activated the PI3K phosphorylation pathway. Moreover, PTE addition altered the relative abundance of the Firmicutes, Proteobacteria, Parabacillus, and Bacteroidetes-like RF16 groups in sow faeces. PTE increased the levels of acetate, propionate, butyrate and isovalerate in the faeces. Conclusions These findings reveal that the addition of PTE during pregnancy and lactation mitigates the effects of processive oxidative stress on offspring development by altering maternal microbial and placental nutrient transport capacity. Graphical Abstract

IntroductionCold stress is the primary factor that limits the growth and development of Kobresia pygmaea in the Tibetan Plateau, China. Chitosan (CTS) has been recognized for its ability to enhance agricultural production and tolerance to stress.MethodsThis study examined the effect of treating seedlings under cold stress with chitosan.Results and DiscussionThe results demonstrated that cold stress inhibited the growth of seedlings and adversely affected the photosynthetic capacity [net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), maximum efficiency of photosystem II (Fv/Fm), quantum yield of photosystem II (φPSII), electron transport rate (ETR), and non-light-induced non-photochemical fluorescence quenching Y(NPQ)] and destroyed PSII and the chloroplast structure. Under regular temperatures, low concentrations of CTS (0.005% and 0.01%) inhibited the soluble protein content, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) activity, and photosynthetic capacity. However, the application of 0.015% CTS increased the levels of soluble sugar, fructose, and protein, as well as those of the levels of ions, such as iron and magnesium, chlorophyll, photosynthetic capacity, and the activities of Rubisco, superoxide dismutase, and phenylalanine amino-lyase (PAL). Under cold stress, treatment with CTS decreased the contents of starch and sucrose; improved the contents of fructose, soluble protein, and antioxidants, such as ascorbic acid and glutathione; and enhanced the photosynthesis capacity and the activities of Rubisco, chitinase, and PAL. Exogenous CTS accelerated the development of the vascular bundle, mitigated the damage to chloroplast structure induced by cold, and promoted the formation of well-organized thylakoids and grana lamellae. Additionally, CTS upregulated the expression of genes related to cold tolerance in K. pygmaea, such as KpBSK2/KpERF/KpDRE326. These findings indicate that CTS enhances the cold tolerance in K. pygmaea by improving development of the vascular bundle, increasing the accumulation of solutes and antioxidants, regulating the transformation of carbohydrates, repairing the chloroplast structure, and maintaining the photosynthetic capacity and Rubisco activity.

Introduction Successful reperfusion does not always lead to good neurological outcomes and impaired microcirculation can be one of the underlying causes. Intra-arterial alteplase after mechanical thrombectomy (MT) may improve microcirculation contributing to neurological recovery, but prospective randomised studies are still needed to validate its efficacy and safety. We aim to assess the efficacy and safety of intra-arterial alteplase after MT for acute ischaemic stroke (AIS) with large-vessel occlusion (LVO).Methods and analysis The Intra-arterial Alteplase for Acute Ischaemic Stroke After Mechanical Thrombectomy (PEARL) study is a multicentre, prospective, open-label, blinded-endpoint, randomised controlled trial. We consecutively screen AIS patients with anterior circulation LVO and National Institute of Health Stroke Scale of 6–25, who reach stable expanded Thrombolysis in Cerebral Infarction scores of 2b50-3 on angiography after MT. Eligible participants are 1:1 randomly assigned to the experimental group and the control group. Participants in the experimental group will receive intra-arterial alteplase (0.225 mg/kg and a maximum dose of 20 mg) after MT and standard medical treatment, while those in the control group will receive standard medical treatment alone after the procedure. The primary outcome is the proportion of patients with a 90-day modified Rankin scale of 0–1. A total of 324 participants are required to test the superiority hypothesis with 80% power at a two-tailed significance level of 0.05.Ethics and dissemination This study has been approved by the Ethics Committee of Sun Yat-sen Memorial Hospital, Sun Yat-sen University (SYSKY-2023-390-02) and will be conducted following the Declaration of Helsinki. Ethical approvals have been obtained separately for all centres participating in the study. Study results will be published in peer-reviewed academic journals.Trial registration number NCT05856851.

Abstract Background Kobreisa littledalei, belonging to the Cyperaceae family is the first Kobresia species with a reference genome and the most dominant species in Qinghai-Tibet Plateau alpine meadows. It has several resistance genes which could be used to breed improved crop varieties. Reverse Transcription Quantitative Real-Time Polymerase Chain Reaction (RT-qPCR) is a popular and accurate gene expression analysis method. Its reliability depends on the expression levels of reference genes, which vary by species, tissues and environments. However, K.littledalei lacks a stable and normalized reference gene for RT-qPCR analysis. Results The stability of 13 potential reference genes was tested and the stable reference genes were selected for RT-qPCR normalization for the expression analysis in the different tissues of K. littledalei under two abiotic stresses (salt and drought) and two hormonal treatments (abscisic acid (ABA) and gibberellin (GA)). Five algorithms were used to assess the stability of putative reference genes. The results showed a variation amongst the methods, and the same reference genes showed tissue expression differences under the same conditions. The stability of combining two reference genes was better than a single one. The expression levels of ACTIN were stable in leaves and stems under normal conditions, in leaves under drought stress and in roots under ABA treatment. The expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression was stable in the roots under the control conditions and salt stress and in stems exposed to drought stress. Expression levels of superoxide dismutase (SOD) were stable in stems of ABA-treated plants and in the roots under drought stress. Moreover, RPL6 expression was stable in the leaves and stems under salt stress and in the stems of the GA-treated plants. EF1-alpha expression was stable in leaves under ABA and GA treatments. The expression levels of 28 S were stable in the roots under GA treatment. In general, ACTIN and GAPDH could be employed as housekeeping genes for K. littledalei under different treatments. Conclusion This study identified the best RT-qPCR reference genes for different K. littledalei tissues under five experimental conditions. ACTIN and GAPDH genes can be employed as the ideal housekeeping genes for expression analysis under different conditions. This is the first study to investigate the stable reference genes for normalized gene expression analysis of K. littledalei under different conditions. The results could aid molecular biology and gene function research on Kobresia and other related species.

Abstract Background Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy metabolism, and the mechanisms by which it regulates host energy metabolism at cold temperatures have rarely been illustrated. In this study, we evaluated the status of glycolipid metabolism and oxidative stress in pigs based on the gut-liver axis and propose that AMP-activated protein kinase (AMPK) is a key target for alleviating energy stress at cold temperatures by dietary fat supplementation. Results Dietary fat supplementation alleviated the negative effects of cold temperatures on growth performance and digestive enzymes, while hormonal homeostasis was also restored. Moreover, cold temperature exposure increased glucose transport in the jejunum. In contrast, we observed abnormalities in lipid metabolism, which was characterized by the accumulation of bile acids in the ileum and plasma. In addition, the results of the ileal metabolomic analysis were consistent with the energy metabolism measurements in the jejunum, and dietary fat supplementation increased the activity of the mitochondrial respiratory chain and lipid metabolism. As the central nexus of energy metabolism, the state of glycolipid metabolism and oxidative stress in the liver are inconsistent with that in the small intestine. Specifically, we found that cold temperature exposure increased glucose transport in the liver, which fully validates the idea that hormones can act on the liver to regulate glucose output. Additionally, dietary fat supplementation inhibited glucose transport and glycolysis, but increased gluconeogenesis, bile acid cycling, and lipid metabolism. Sustained activation of AMPK, which an energy receptor and regulator, leads to oxidative stress and apoptosis in the liver; dietary fat supplementation alleviates energy stress by reducing AMPK phosphorylation. Conclusions Cold stress reduced the growth performance and aggravated glycolipid metabolism disorders and oxidative stress damage in pigs. Dietary fat supplementation improved growth performance and alleviated cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis. In this study, we highlight the importance of AMPK in dietary fat supplementation-mediated alleviation of host energy stress in response to environmental changes.

Black soldier fly larvae (BSFL) convert kitchen waste into high-quality insect feed. However, the optimal amount of auxiliary materials needed to improve the physical and chemical properties of kitchen waste and enhance BSFL bioconversion efficiency remains unresolved. In this study, maize stover and BSFL frass were added to kitchen waste (in groups G2 and G3, respectively) to explore their effects on the growth performance and bioconversion efficiency of BSFL. The group with only kitchen waste, without the addition of maize stover or BSF frass, was used as the control group and labeled as G1. On the 5th day, the body length of the BSFL in the G2 group was significantly greater than that in G1 and G3 (p < 0.05). The dry matter weight loss rate in the G3 group was significantly lower compared to that of G1 and G2 (p < 0.05), and the feed conversion rate (FCR) of G1 was significantly lower than that of G2 and G3 (p < 0.01). In summary, adding maize stover and BSFL frass increased BSFL feed intake and improved body weight gain. However, these additives did not significantly enhance BSFL bioconversion efficiency. The organic matter in maize stover and BSFL frass was utilized by the BSFL, and the heavy metal levels in each group of BSFL did not exceed standard limits.

Objectives: Angiogenic T cells (Tang) are crucial in promoting angiogenesis, with the loss of CD28 serving as a marker for highly differentiated and senescent T cells. This study aims to investigate the characteristics and potential roles of CD8+CD28null Tang in patients with ANCA-associated vasculitis (AAV). Methods: A cohort of AAV patients and matched healthy controls (HCs) were analyzed. Flow cytometry was used to assess the profiles of circulating CD8+CD28null Tang. In vitro functional assays were performed to evaluate the pathogenic properties of CD8+CD28null Tang. Results: CD8+CD28null Tang levels were significantly higher in the peripheral blood of AAV patients compared to HCs, and their levels were further increased in AAV patients with MPO⁺, p-ANCA⁺, or interstitial lung disease compared to their respective control groups. Additionally, there was a positive correlation between both the percentage and absolute count of CD8+CD28null Tang and the Birmingham Vasculitis Activity Score (BVAS). In patients with a good treatment response, both the percentage and absolute count of CD8+CD28null Tang were significantly reduced, and this reduction was positively correlated with the decrease in BVAS scores. In vitro studies revealed that CD8+CD28null Tang displayed enhanced chemotactic properties, induced apoptosis in human umbilical vein endothelial cells (HUVECs), and inhibited their proliferation, migration, and tube formation. Conclusions: AAV patients exhibit increased levels of circulating CD8+CD28null Tang, which can be reduced following effective treatment. Furthermore, CD8+CD28null Tang may contribute to the pathogenesis of AAV by promoting apoptosis and inhibiting the proliferation, migration, and tube formation of HUVECs.

Abstract Alfalfa, an essential forage crop known for its high yield, nutritional value, and strong adaptability, has been widely cultivated worldwide. The yield and quality of alfalfa are frequently jeopardized due to environmental degradation. Lignin, a constituent of the cell wall, enhances plant resistance to abiotic stress, which often causes osmotic stress in plant cells. However, how lignin responds to osmotic stress in leaves remains unclear. This study explored the effects of osmotic stress on lignin accumulation and the contents of intermediate metabolites involved in lignin synthesis in alfalfa leaves. Osmotic stress caused an increase in lignin accumulation and the alteration of core enzyme activities and gene expression in the phenylpropanoid pathway. We identified five hub genes (CSE, CCR, CADa, CADb, and POD) and thirty edge genes (including WRKYs, MYBs, and UBPs) by integrating transcriptome and metabolome analyses. In addition, ABA and ethylene signaling induced by osmotic stress regulated lignin biosynthesis in a contradictory way. These findings contribute to a new theoretical foundation for the breeding of high-quality and resistant alfalfa varieties.

Flexible hafnia-based ferroelectric memories are arousing much interest with the ever-growing demands for nonvolatile data storage in wearable electronic devices. Here, high-quality flexible Hf0.5Zr0.5O2 membranes with robust ferroelectricity were fabricated on inorganic pliable mica substrates via an atomic layer deposition technique. The flexible Hf0.5Zr0.5O2 thin membranes with a thickness of ∼8 nm exhibit a high remanent polarization of ∼16 μC/cm2, which possess very robust polarization switching endurance (>1010 cycles, two orders of magnitude better than reported flexible HfO2-based films) and superior retention ability (expected >10 years). In particular, stable ferroelectric polarization as well as excellent endurance and retention performance show negligible degradations under 6 mm radius bending conditions or after 104 bending cycles with a 6 mm bending radius. These results mark a crucial step in the development of flexible hafnium oxide-based ferroelectric memories for wearable electronic devices.

Screening genotypes with optimal root traits presents a promising breeding strategy for enhancing adaptability to abiotic stresses and improving resource use efficiency. This study evaluated root traits of 100 winter wheat genotypes under four treatments: control (C), low phosphorus (LP), PEG-induced drought (D), and a combination of LP and drought (DLP), using a semi-hydroponic phenotyping platform. Significant variations in root traits were observed 65 days after transplanting, with over 80% of traits being significantly affected by drought, phosphorus, or their interactions. Biomass and phosphorus content decreased under LP and drought, while root length and diameter in deeper layers increased, especially under drought stress. Combined stress led to the most severe reductions in biomass, P-content, and leaf number. Phosphorus acquisition efficiency was positively correlated with root length but inversely related to stress tolerance. High heritability traits, such as root number, root length, maximum root depth, leaf number, and biomass, hold potential for breeding programs focused on environmental adaptation, resource efficiency, and yield improvement. The substantial genotypic variation in root morphology under stress conditions highlights the potential for breeding stress-resilient wheat genotypes. This finding lays a foundation for wheat-breeding initiatives aimed at developing genotypes better suited to prevailing environmental conditions.

This study aimed to investigate the effects of different defatting methods of black soldier fly (Hermetia illucens) larvae meal (BSFM) on the metabolic energy and nutrient digestibility in laying hens. Sixty young laying hens (Hy-Line W-36) aged 63 days were randomly divided into two groups (G1 and G2), each with five replicates of six hens housed in individual cages. Group G1 was fed 25% pressed black soldier fly meal (BSFMp) and 75% basal diet, and Group G2 was fed 25% extracted black soldier fly meal (BSFMe) and a 75% basal diet. Both diets included 5 g/kg chromium oxide as an external marker. A 7-day preliminary trial was followed by a 4-day experimental period. The results indicate that pressing and extracting significantly affected the digestibility of crude fat and total energy in BSFM, with BSFMp showing significantly higher crude fat digestibility than BSFMe. Similarly, total energy digestibility was also significantly higher in BSFMp. However, there were no significant differences in dry matter, organic matter, and crude protein digestibility between the two processing methods. The apparent metabolic energy values of BSFMp and BSFMe were 16.34 and 12.41 MJ/kg, respectively, showing a significant difference. The nitrogen-corrected metabolic energy values were 15.89 MJ/kg in BSFMp and 11.93 MJ/kg in BSFMe, indicating a highly significant difference. The digestibility of arginine and leucine in BSFMp was significantly higher than in BSFMe, while differences in lysine, cystine, threonine, tryptophan, and isoleucine were not significant. In conclusion, both defatting methods of BSFM had no adverse effects on the metabolic energy and nutrient digestibility in young laying hens, but BSFMp demonstrated better effects on the digestibility of metabolic energy and nutrients in the feed for young laying hens.

Medicago truncatula is a key model plant for studying legume plants, particularly alfalfa (Medicago sativa), due to its well-defined genetic background. Plant-specific GASA (Gibberellic Acid Stimulated Arabidopsis) genes play various roles in plant growth and development, abiotic stress, and hormone responses. However, limited information is available on GASA research in Medicago. In this study, 26 MtGASAs were identified and analyzed for its structure, evolution, and expressions. Sequence alignments and phylogeny revealed that 26 MtGASAs containing conserved GASA domains were classified into three clades. The chromosomal locations and gene synteny revealed segmental and tandem repetition evolution. Analysis of cis-regulatory elements indicates that family members likely influence various hormone signaling pathways and stress-related mechanisms. Moreover, the RNA-seq and qRT-PCR analyses revealed that 26 MtGASAs were extensively involved in abiotic stresses and hormone responses. Notably, seven MtGASA genes (MtGASA1, 10, 12, 17, 23, 25 and 26) were all dramatically activated by NaCl and Mannitol treatments, and four MtGASAs (MtGASA7, 10, 23 and 24) were significant activated by GA3, PBZ, ABA, and MeJA treatments. Collectively, this study is the first to identify and describe GASA genes in Medicago on a genome-wide scale. The results establish a basis for functional characterization, showing that these proteins are essential in responding to various abiotic stresses and hormonal signals.

Mammals in northern regions chronically suffer from low temperatures during autumn-winter seasons. The aim of this study was to investigate the response of intestinal amino acid transport and the amino acid pool in muscle to chronic cold exposure via Min pig models (cold adaptation) and Yorkshire pig models (non-cold adaptation). Furthermore, this study explored the beneficial effects of glucose supplementation on small intestinal amino acid transport and amino acid pool in muscle of cold-exposed Yorkshire pigs. Min pigs (Exp. 1) and Yorkshire pigs (Exp. 2) were divided into a control group (17 °C, n = 6) and chronic cold exposure group (7 °C, n = 6), respectively. Twelve Yorkshire pigs (Exp. 3) were divided into a cold control group and cold glucose supplementation group (8 °C). The results showed that chronic cold exposure inhibited peptide transporter protein 1 (PepT1) and excitatory amino acid transporter 3 (EAAT3) expression in ileal mucosa and cationic amino acid transporter-1 (CAT-1) in the jejunal mucosa of Yorkshire pigs (P

Room temperature electric field controlled magnetism is extremely promising for the next-generation high-performance spintronic devices. Here, based on the ferroelectric switching driven oxygen ion migration in the Ta/Co/BiFeO3/SrRuO3 heterostructures, the magnetic moment, magnetic coercive field, exchange bias field, and junction resistance are reversibly manipulated by tuning the ferroelectric polarization of the BiFeO3 layer. All these phenomena are consistently explained by the oxygen ion migration induced CoOx/Co redox effect, which is evidenced by the synchrotron X-ray absorption spectroscopy measurements. Interestingly, owing to the controllable ferroelectric switching dynamics of the BiFeO3 thin film, the magnetic coercive field of the Co thin film can be continuously and precisely tuned by controlling the ferroelectric polarization of the BiFeO3 thin film, and the manipulating speed of the voltage control of magnetism can be fast to 100 ns. This nonvolatile, stable, reversible, fast, and reproducible voltage control of magnetism shows great potential for designing low-power and high-speed spintronics.

Abstract The application of nanotechnology in agriculture can remarkably improve the cultivation and growth of crop plants. Many studies showed that nanoparticles (NPs) made plants grow more vigorously. Light can make NPs aggregated, leading to the reduction of the NPs toxicity. In addition, treatment with NPs had a “hormesis effect” on plants. In this study, light-induced silver nanoparticles (AgNPs) were synthesized by using the alfalfa (Medicago sativa L.) extracts, and then the optimal synthetic condition was determined. Light-induced AgNPs were aggregated, spherical and pink, and they were coated with esters, phenols, acids, terpenes, amino acids and sugars, which were the compositions of alfalfa extracts. The concentration of free Ag+ was less than 2 % of the AgNPs concentration. Through nanopriming, Ag+ got into the seedlings and caused the impact of AgNPs on alfalfa. Compared with the control group, low concentration of light-induced AgNPs had a positive effect on the photosynthesis. It was also harmless to the leaf cells, and there was no elongation effect on shoots. Although high concentration of AgNPs was especially beneficial to root elongation, it had a slight toxic effect on seedlings due to the accumulation of silver. With the increase of AgNPs concentration, the content of silver in the seedlings increased and the silver enriched in plants was at the mg/kg level. Just as available research reported the toxicity of NPs can be reduced by using suitable synthesis and application methods, the present light induction, active material encapsulation and nanopriming minimized the toxicity of AgNPs to plants, enhancing the antioxidant enzyme system. Graphical Abstract

Amidst the outbreak of the Corona Virus Disease 2019 (COVID-19), there has been a pivotal shift in nutritional focus towards adopting healthier lifestyles to enhance immune function. The successive resurgence of COVID-19 serves as a stark reminder that prioritizing the enhancement of our own immune systems is of paramount importance. Eggs are nutritious, productive, cost-effective, and affordable for consumption. Likewise, eggs are exclusive among the numerous ways consumers can obtain high-quality animal protein. Egg proteins and their peptide derivatives are abundant and biologically active and have significant therapeutic effects on chronic diseases induced by a variety of factors, including metabolic syndrome, making eggs an important raw material for the study of proteins and peptide-active substances. This paper reviewed methods for the isolation and purification of avian egg proteins and their derived peptides; the effects of the proteins and peptides in enhancing the body’s immunity, lowering blood pressure and expression levels of inflammatory factors; as well as the potential of the proteins and peptides in reducing the risk of chronic diseases such as osteoporosis and cardiovascular disease. This review was written with the expectation that it would provide a comprehensive understanding of the potential value of poultry egg proteins for maintaining health.

Background: Severe acute respiratory syndrome coronavirus (SARS-CoVs) have emerged as a global health threat, which had caused a high rate of mortality. There is an urgent need to find effective drugs against these viruses.Objective: This study aims to predict the activity of unsymmetrical aromatic disulfides by constructing a QSAR model, and to design new compounds according to the structural and physicochemical attributes responsible for higher activity towards SARS-CoVs main protease.Methods: All molecules were constructed in ChemOffice software and molecular descriptors were calculated by CODESSA software. A regression-based linear heuristic method was established by changing descriptors datasets and calculating predicted IC50 values of compounds. Then, some new compounds were designed according to molecular descriptors from the heuristic method model. The compounds with predicted values smaller than a set point were constantly screened out. Finally, the properties analysis and molecular docking were conducted to further understand the structure-activity relationships of these finalized compounds.Results: The heuristic method explored the various descriptors responsible for bioactivity and gained the best linear model with R2 0.87. The success of the model fully passed the testing set validation, proving that the model has both high statistical significance and excellent predictive ability. A total of 5 compounds with ideal predicted IC50 were found from the 96 newly designed derivatives and their properties analyze was carried out. Molecular docking experiments were conducted for the optimal compound 31a, which has the best compound activity with good target protein binding capability.Conclusion: The heuristic method was quite reliable for predicting IC50 values of unsymmetrical aromatic disulfides. The present research provides meaningful guidance for further exploration of the highly active inhibitors for SARS-CoVs.

Brain-inspired computing demands high-performance synapses. Here, the authors report a subnanosecond ferroelectric tunnel junction with 256 conductance states, 109 endurance, and 5.3 fJ/bit energy consumption, satisfactory to build synaptic devices.

Aedes aegypti abundance in residential estates is hypothesized to contribute to localised outbreaks of dengue in Singapore. Knowing the factors in the urban environment underlying high Ae. aegypti abundance could guide intervention efforts to reduce Ae. aegypti breeding and the incidence of dengue. In this study, objective data on Ae. aegypti abundance in public apartment blocks estimated by Singapore's nationally representative Gravitrap surveillance system was obtained from the National Environmental Agency. Low and high abundance status public apartment blocks were classified based on the Gravitrap Aegypti Index, corresponding to the lowest and highest quartiles respectively. An environmental case-control study was conducted, wherein a blinded assessment of urban features hypothesised to form breeding habitats was conducted in 50 randomly sampled public apartment blocks with low and high abundance statuses each. Logistic regression was performed to identify features that correlated with abundance status. A multivariable logistic model was created to determine key urban features found in corridors and void decks which were predictive of the Ae. aegypti abundance status of the public apartment block. At a statistical level of significance of 0.20, the presence of gully traps [Odds Ratio (OR): 1.34, 95% Confidence Interval (CI): 1.10, 1.66], age of the public apartment block [OR: 2.23, 95% CI: 1.48, 3.60], housing price [OR: 0.33, 95% CI: 0.16, 0.61] and corridor cleanliness [OR: 0.67, 95% CI: 0.40, 1.07] were identified as important predictors of abundance status. To reduce Ae. aegypti abundance around public apartment blocks and potential onward dengue transmission, gully traps could be remodelled or replaced by other drainage types. Routine inspections of Ae. aegypti breeding should be targeted at older and low-income neighbourhoods. Campaigns for cleaner corridors should be promoted.

Glyphosate-based herbicides (GBHs) are the most widely used pesticide worldwide and can provoke placental injury. However, whether and how GBHs damage angiogenesis in the placenta is not yet known. This work evaluated the safety of glyphosate on pregnant sows based on the limit level by governments and investigated the effects and mechanism of Low-GBHs (20 mg/kg) and High-GBHs (100 mg/kg) exposure on placental angiogenesis. Results showed that gestational exposure to GBHs decreased placental vessel density and cell multiplication by interfering with the expression of VEGFA, PLGF, VEGFr2 and Hand2 (indicators of angiogenesis), which may be in relation to oxidative stress-induced disorders of mitochondrial fission and fusion as well as the impaired function of the mitochondrial respiratory chain. Additionally, GBHs destroyed barrier function and nutrient transport in the placenta, and was accompanied by jejunum oxidative stress in newborn piglets. However, GBHs exposure had no significant differences on sow reproductive performance. As a natural antioxidant, betaine treatment protected placenta and newborn piglets against GBHs-induced damage. In conclusion, GBHs impaired placental angiogenesis and function and further damaged the health of postnatal progeny, these effects may be linked to mitochondrial dysfunction. Betaine treatment following glyphosate exposure provided modest relief.

Spectrometers are key instruments in diverse fields, notably in medical and biosensing applications. Recent advancements in nanophotonics and computational techniques have contributed to new spectrometer designs characterized by miniaturization and enhanced performance. This paper presents a comprehensive review of miniaturized computational spectrometers (MCS). We examine major MCS designs based on waveguides, random structures, nanowires, photonic crystals, and more. Additionally, we delve into computational methodologies that facilitate their operation, including compressive sensing and deep learning. We also compare various structural models and highlight their unique features. This review also emphasizes the growing applications of MCS in biosensing and consumer electronics and provides a thoughtful perspective on their future potential. Lastly, we discuss potential avenues for future research and applications.

With the development and popularization of the Beidou-3 navigation satellite system (BDS-3), to ensure its unique short message function, it is necessary to integrate a radio frequency (RF) transmitting circuit with high performance in the BDS-3 terminal. As the key device in an RF transmitting circuit, the RF power amplifier (PA) largely determines the comprehensive performance of the circuit with its transmission power, efficiency, linearity, and integration. Therefore, in this paper, an L-band highly integrated PA chip compatible with 3 W and 5 W output power is designed in InGaP/GaAs heterojunction bipolar transistor (HBT) technology combined with temperature-insensitive adaptive bias technology, class-F harmonic suppression technology, analog pre-distortion technology, temperature-insensitive adaptive power detection technology, and land grid array (LGA) packaging technology. Additionally, three auxiliary platforms are proposed, dedicated to the simulation and optimization of the same type of PA designs. The simulation results show that at the supply voltage of 5 V and 3.5 V, the linear gain of the PA chip reaches 39.4 dB and 38.7 dB, respectively; the output power at 1 dB compression point (P1dB) reaches 37.5 dBm and 35.1 dBm, respectively; the saturated output power (Psat) reaches 38.2 dBm and 36.2 dBm, respectively; the power added efficiency (PAE) reaches 51.7% and 48.2%, respectively; and the higher harmonic suppression ratios are less than −62 dBc and −65 dBc, respectively. The size of the PA chip is only 6 × 4 × 1 mm3. The results also show that the PA chip has high gain, high efficiency, and high linearity under both output power conditions, which has obvious advantages over similar PA chip designs and can meet the short message function of the BDS-3 terminal in various application scenarios.

This work provides a mechanistic insight into the effects of different type of N-doped carbon-supported catalysts on the synthesis of VAc by the acetylene method. The introduction of N-doping can enhance the adsorption of acetylene and acetic acid molecules onto the catalyst supports. The N6–3 surface which with three pyridinic-N shows the most adsorption stability for both acetylene and acetic acid molecules, and facilitates the synthesis of VAc efficiently. While the N6 surface which with the pyridinic-N is obstructive to the VAc formation.

In the long-term growth process, alfalfa rhizosphere forms specific microbiome to provide nutrition for its growth and development. However, the effects of different perennial alfalfa cultivars on changes in the rhizosphere soil characteristics and microbiome are not well understood. In this study, 12 perennial alfalfa cultivars were grown continuously for eight years. Rhizosphere samples were tested using Illumina sequencing of the 16S rRNA gene coupled with co-occurrence network analysis to explore the relationship between alfalfa (biomass and crude protein content), soil properties, and the microbial composition and diversity. Redundancy analysis showed SOC and pH had the greatest impact on the composition of the rhizosphere microbial community. Moreover, microbial diversity also contributes to microbial composition. Soil properties (AP, EC, SOC and pH) exhibited a significant positive correlation with soil bacterial communities, which was attributed to the differences between plant cultivars. Partial least squares path modeling (PLS-PM) revealed that microbial biomass and community composition rather than diversity, are the dominant determinants in the rhizosphere soil nitrogen content of perennial alfalfa. Our findings demonstrate that the soil microbial biomass and composition of rhizosphere bacterial communities are strongly affected by cultivar, driving the changes in soil nitrogen content, and variances in the selective capacities of plants.

ObjectivesThis study aimed at establishing a mouse model of immune-related adverse in humanized BALB/c-hPD1/hCTLA4 mice to investigate their potential pathogenesis and explore therapeutic targets for immune-related arthritis and pneumonitis.MethodsHumanized BALB/c-hPD1/hCTLA4 mice were injected with vehicle or collagen-specific antibodies (CA) and immune checkpoint inhibitors (ICI, ipilimumab, anti-human CTLA-4; and nivolumab, anti-human PD-1), and some mice were treated with anti-TNF-α antibody, leading to the control, collagen antibody-induced arthritis (CAIA), CAIA+ICI and treatment groups. The severity of clinical arthritis and pneumonitis in mice was monitored longitudinally and the pathological changes in the joints and lungs were histologically analyzed and the contents of lung hydroxyproline were measured. The frequency of different subsets of T cells was analyzed by flow cytometry and multiplex immunofluorescency.ResultsCompared with the control, the ICI group of mice developed the delayed onset of moderate degrees of arthritis while the CAIA+ICI group of mice exhibited the early onset of severe arthritis. Treatment with ICI caused severe pneumonitis, especially in the mice with CA. Flow cytometry analysis indicated a significantly higher frequency of splenic TNF-α+CD4+ and TNF-α+CD8+ T cells, but not other subsets of T cells tested, in the CAIA+ICI group of mice, relative to that in other groups of mice. Treatment with anti-TNF-α significantly mitigated the severity of arthritis and pneumonitis as well as deposition of collagen in lung of mice. The treatment also decreased the frequency of TNF-α+CD4+ and TNF-α+CD8+ T cells as well as effector memory T cells in the periphery lymph orangs and lungs of mice.ConclusionsWe successfully established a humanized mouse model of ICI-related severe arthritis and pneumonitis with a higher frequency of TNF-α+ T cells, which were significantly mitigated by anti-TNF-α treatment. Conceptually, ICI treatment can induce multiple autoimmune-like diseases in autoimmune-prone individuals and TNF-α+ T cells may be therapeutic targets for intervention of immune-related arthritis and pneumonitis.

Abstract Background Despite the licensure of the world’s first dengue vaccine and the current development of additional vaccine candidates, successful Aedes control remains critical to the reduction of dengue virus transmission. To date, there is still limited literature that attempts to explain the spatio-temporal population dynamics of Aedes mosquitoes within a single city, which hinders the development of more effective citywide vector control strategies. Narrowing this knowledge gap requires consistent and longitudinal measurement of Aedes abundance across the city as well as examination of relationships between variables on a much finer scale. Methods We utilized a high-resolution longitudinal dataset generated from Singapore’s islandwide Gravitrap surveillance system over a 2-year period and built a Bayesian hierarchical model to explain the spatio-temporal dynamics of Aedes aegypti and Aedes albopictus in relation to a wide range of environmental and anthropogenic variables. We also created a baseline during our model assessment to serve as a benchmark to be compared with the model’s out-of-sample prediction/forecast accuracy as measured by the mean absolute error. Results For both Aedes species, building age and nearby managed vegetation cover were found to have a significant positive association with the mean mosquito abundance, with the former being the strongest predictor. We also observed substantial evidence of a nonlinear effect of weekly maximum temperature on the Aedes abundance. Our models generally yielded modest but statistically significant reductions in the out-of-sample prediction/forecast error relative to the baseline. Conclusions Our findings suggest that public residential estates with older buildings and more nearby managed vegetation should be prioritized for vector control inspections and community advocacy to reduce the abundance of Aedes mosquitoes and the risk of dengue transmission.

Abstract Background Zika virus (ZIKV) emerged as a global epidemic in 2015–2016 from Latin America with its true geographical extent remaining unclear due to widely presumed underreporting. The identification of locations with potential and unknown spread of ZIKV is a key yet understudied component for outbreak preparedness. Here, we aim to identify locations at a high risk of cryptic ZIKV spread during 2015–2016 to further the understanding of the global ZIKV epidemiology, which is critical for the mitigation of the risk of future epidemics. Methods We developed an importation simulation model to estimate the weekly number of ZIKV infections imported in each susceptible spatial unit (i.e. location that did not report any autochthonous Zika cases during 2015–2016), integrating epidemiological, demographic, and travel data as model inputs. Thereafter, a global risk model was applied to estimate the weekly ZIKV transmissibility during 2015–2016 for each location. Finally, we assessed the risk of onward ZIKV spread following importation in each susceptible spatial unit to identify locations with a high potential for cryptic ZIKV spread during 2015–2016. Results We have found 24 susceptible spatial units that were likely to have experienced cryptic ZIKV spread during 2015–2016, of which 10 continue to have a high risk estimate within a highly conservative scenario, namely, Luanda in Angola, Banten in Indonesia, Maharashtra in India, Lagos in Nigeria, Taiwan and Guangdong in China, Dakar in Senegal, Maputo in Mozambique, Kinshasa in Congo DRC, and Pool in Congo. Notably, among the 24 susceptible spatial units identified, some have reported their first ZIKV outbreaks since 2017, thus adding to the credibility of our results (derived using 2015–2016 data only). Conclusion Our study has provided valuable insights into the potentially high-risk locations for cryptic ZIKV circulation during the 2015–2016 pandemic and has also laid a foundation for future studies that attempt to further narrow this key knowledge gap. Our modelling framework can be adapted to identify areas with likely unknown spread of other emerging vector-borne diseases, which has important implications for public health readiness especially in resource-limited settings.

Abstract Background The emergence of a novel coronavirus (SARS-CoV-2) in Wuhan, China, at the end of 2019 has caused widespread transmission around the world. As new epicentres in Europe and America have arisen, of particular concern is the increased number of imported coronavirus disease 2019 (COVID-19) cases in Africa, where the impact of the pandemic could be more severe. We aim to estimate the number of COVID-19 cases imported from 12 major epicentres in Europe and America to each African country, as well as the probability of reaching 10,000 cases in total by the end of March, April, May, and June following viral introduction. Methods We used the reported number of cases imported from the 12 major epicentres in Europe and America to Singapore, as well as flight data, to estimate the number of imported cases in each African country. Under the assumption that Singapore has detected all the imported cases, the estimates for Africa were thus conservative. We then propagated the uncertainty in the imported case count estimates to simulate the onward spread of the virus, until 10,000 cases are reached or the end of June, whichever is earlier. Specifically, 1,000 simulations were run separately under four different combinations of parameter values to test the sensitivity of our results. Results We estimated Morocco, Algeria, South Africa, Egypt, Tunisia, and Nigeria as having the largest number of COVID-19 cases imported from the 12 major epicentres. Based on our 1,000 simulation runs, Morocco and Algeria’s estimated probability of reaching 10,000 cases by end of March was close to 100% under all scenarios. In particular, we identified countries with less than 1,000 cases in total reported by end of June whilst the estimated probability of reaching 10,000 cases by then was higher than 50% even under the most optimistic scenario. Conclusions Our study highlights particular countries that are likely to reach (or have reached) 10,000 cases far earlier than the reported data suggest, calling for the prioritization of resources to mitigate the further spread of the epidemic.

Modern electronics and electric power grids require high performance polymer-based dielectric nanocomposites. To realize large-scale applications, the energy density of nanocomposites needs to be further increased. Here, we demonstrate a remarkable improvement in energy density of poly(vinylidene fluoride) (PVDF) matrix upon the incorporation of high-κ Bi4.2K0.8Fe2O9+δ (BKFO) nanobelts. High aspect ratio BKFO nanobelts can enhance the Young's moduli of the nanocomposites and increase the path tortuosity of electrical trees, which are favorable for increasing the breakdown strength of the system. Thus, the dielectric constant and breakdown strength increase simultaneously at a low volume fraction (0.35 vol%) of BKFO nanobelts, and an ultrahigh recoverable energy density of 25.4 J/cm3 is achieved. These results provide a strategy to develop high performance flexible high-energy-density devices. Keywords: Dielectric nanocomposite, Energy storage, Nanobelt, Breakdown strength

Memristor devices based on ferroelectric tunnel junctions are promising, but suffer from quite slow switching times. Here, the authors report on ultrafast switching times at and above room temperature of 600ps in Ag/BaTiO3/Nb:SrTiO3 based ferroelectric tunnel junctions.

ObjectivesThis study aimed to investigate the changes in quantity and function of T helper (Th)-like T regulatory (Treg) cell subsets in peripheral blood (PB) and synovial fluid (SF) of rheumatoid arthritis (RA) patients and to understand their relationship with disease activity.MethodsA total of 86 RA patients and 76 gender and age-matched healthy controls (HC) were enrolled in this study. Th-like Treg frequency and function were determined using flow cytometry. The inhibitory function of Th-like Treg cells was detected using an in vitro co-culture suppression assay.ResultsThe proportion and absolute number of Th1-like Treg cells from RA PB and RA SF were significantly higher than those of HC PB. In RA SF, the proportions of Treg cells and Th1-like Treg cells were significantly lower in the elevated erythrocyte sedimentation rate or the C-Reactive Protein group, and in the positive groups of anti-CCP antibody and anti-MCV antibody. Additionally, the proportions of Treg cells and Th1-like Treg cells from RA SF were negatively correlated with disease activity. However, the expression levels of CD73 and TGF-β1 in Th1-like Treg cells were decreased, and these Treg cells could not effectively inhibit the proliferation of effector T (Teff) cells.ConclusionOur data indicate that Th1-like Treg cells are the predominant Treg cell subset in RA SF, but their suppressive function is defective. Improving the function of Th1-like Treg cells may control inflammation in joints and provide new strategies for Treg-targeted therapies in RA.

As the most widespread viral infection transmitted by the Aedes mosquitoes, dengue has been estimated to cause 51 million febrile disease cases globally each year. Although sustained vector control remains key to reducing the burden of dengue, current understanding of the key factors that explain the observed variation in the short- and long-term vector control effectiveness across different transmission settings remains limited. We used a detailed individual-based model to simulate dengue transmission with and without sustained vector control over a 30-year time frame, under different transmission scenarios. Vector control effectiveness was derived for different time windows within the 30-year intervention period. We then used the extreme gradient boosting algorithm to predict the effectiveness of vector control given the simulation parameters, and the resulting machine learning model was interpreted using Shapley Additive Explanations. According to our simulation outputs, dengue transmission would be nearly eliminated during the early stage of sustained and intensive vector control, but over time incidence would gradually bounce back to the pre-intervention level unless the intervention is implemented at a very high level of intensity. The time point at which intervention ceases to be effective is strongly influenced not only by the intensity of vector control, but also by the pre-intervention transmission intensity and the individual-level heterogeneity in biting risk. Moreover, the impact of many transmission model parameters on the intervention effectiveness is shown to be modified by the intensity of vector control, as well as to vary over time. Our study has identified some of the critical drivers for the difference in the time-varying effectiveness of sustained vector control across different dengue endemic settings, and the insights obtained will be useful to inform future model-based studies that seek to predict the impact of dengue vector control in their local contexts.

A commonly used method of gesture recognition is the use of sensor technology. Typically, technology detecting Earth’s magnetic field is used in indoor positioning, and magnetic detection technology serves as a redundant method for gesture recognition devices. In this paper, we propose a novel system that utilizes multiple sensors measuring Earth’s magnetic field to collect data and perform gesture recognition through a one-dimensional convolutional neural network algorithm. By applying the detection of Earth’s magnetic field to gesture recognition, our system significantly improves the accuracy of recognition through a one-dimensional (1D) neural network algorithm. We conducted experiments where we collected and recognized American Sign Language standard letters, and achieved an accuracy rate close to 97%. Our experimental results demonstrate that this gesture recognition system using magnetic field sensors and a one-dimensional neural network algorithm is feasible for practical applications. Furthermore, our approach reduces the complexity of the device compared to the gesture recognition method based on artificial magnetic fields, while maintaining high recognition accuracy and not limiting the user’s hand movements. This technology holds great promise for the field of human–computer interaction.

Rare earth elements (REEs) of low concentration are usually beneficial to plant growth, while they are toxic at high concentrations. The effects of treatment with lanthanum (La) (10 and 20 μM), cerium (Ce) (10 and 20 μM), and terbium (Tb) (10 and 20 μM) on seedling growth of alfalfa (Medicago sativa L.), which is one of the most important perennial leguminous forages in the world, were studied. The results showed that all three REE treatments quickened the germination of seeds. The length of shoot under La (20 μM) treatment was significantly shortened (P < 0.05). In addition, treatment with La, Ce, and Tb had a “hormesis effect” on root length. There was a significant decrease in chlorophyll content on treatment with the three REEs, and the degree of decline was in the order of La < Ce < Tb, under the same concentration. In vitro experiments and quantum chemical calculations were further performed to explain why the treatments with REEs reduced the chlorophyll content. In vitro experiments showed that La, Ce, and Tb treatments reduced the absorbance of chlorophyll, and the decrease followed in the order of La > Ce > Tb. Quantum chemical calculations predicted that the decrease in absorption intensity was caused by the reactions between La, Ce, Tb, and chlorophyll, which formed lanthanides-chlorophyll; and there were five types of stable lanthanides-chlorophyll. In conclusion, the decrease in chlorophyll content on treatment with REEs was caused by the change in chlorophyll structure.

Background: Nicaragua experienced a large Zika epidemic in 2016, with up to 50% of the population in Managua infected. With the domesticated Aedes aegypti mosquito as its vector, it is widely assumed that Zika virus transmission occurs within the household and/or via human mobility. We investigated these assumptions by using viral genomes to trace Zika transmission spatially. Methods: We analysed serum samples from 119 paediatric Zika cases participating in the long-standing Paediatric Dengue Cohort Study in Managua, which was expanded to include Zika in 2015. An optimal spanning directed tree was constructed by minimizing the differences in viral sequence diversity composition between patient nodes, where low-frequency variants were used to increase the resolution of the inferred Zika outbreak dynamics. Findings: Out of the 18 houses where pairwise difference in sample collection dates among all the household members was within 30 days, we only found two where viruses from individuals within the same household were up to 10th-most closely linked to each other genetically. We also identified a substantial number of transmission events involving long geographical distances (n=30), as well as potential super-spreading events in the estimated transmission tree. Interpretation: Our finding highlights that community transmission, often involving long geographical distances, played a much more important role in epidemic spread than within-household transmission. Funding: This study was supported by an NUS startup grant (OMS) and grants R01 AI099631 (AB), P01 AI106695 (EH), P01 AI106695-03S1 (FB), and U19 AI118610 (EH) from the US National Institutes of Health.

Abstract Inorganic nanomaterials exhibit superior friction-reduction and anti-wear properties in oils. In this study, 2D layered α-zirconium phosphate (α-ZrP) nanosheets intercalated with different amines have been synthesized to study their dispersion stabilities in lubricating oil and tribological applications. The intercalated amines should be sufficiently long and lipophilic to provide stabilization to α-ZrP nanosheets in mineral oil. The results of tribological tests illustrate that with the addition of well-dispersed nanosheets, the coefficient of friction (COF) and pin volume loss reduce by ~47% and 75%, respectively. The excellent dispersion stability enables the nanosheets to flow into the contact area at the beginning, and thereby protect the rubbing surface. A reduction in the van der Waals forces between the adjacent layers induced by the intercalated amines transforms the friction between adjacent layers from pin disk to sliding, leading to a decrease in the COF under hydrodynamic lubrication. The study provides a new method to enhance the tribological properties via tuning the dispersion stabilities of nanomaterials in oils.

With the development of silicon photonics, dense photonic integrated circuits play a significant role in applications such as light detection and ranging systems, photonic computing accelerators, miniaturized spectrometers, and so on. Recently, extensive research work has been carried out on the phase shifter, which acts as the fundamental building block in the photonic integrated circuit. In this review, we overview different types of silicon photonic phase shifters, including micro-electro-mechanical systems (MEMS), thermo-optics, and free-carrier depletion types, highlighting the MEMS-based ones. The major working principles of these phase shifters are introduced and analyzed. Additionally, the related works are summarized and compared. Moreover, some emerging applications utilizing phase shifters are introduced, such as neuromorphic computing systems, photonic accelerators, multi-purpose processing cores, etc. Finally, a discussion on each kind of phase shifter is given based on the figures of merit.

Mass gathering events have been identified as high-risk environments for community transmission of coronavirus disease 2019 (COVID-19). Empirical estimates of their direct and spill-over effects however remain challenging to identify. In this study, we propose the use of a novel synthetic control framework to obtain causal estimates for direct and spill-over impacts of these events. The Sabah state elections in Malaysia were used as an example for our proposed methodology and we investigate the event's spatial and temporal impacts on COVID-19 transmission. Results indicate an estimated (i) 70.0% of COVID-19 case counts within Sabah post-state election were attributable to the election's direct effect; (ii) 64.4% of COVID-19 cases in the rest of Malaysia post-state election were attributable to the election's spill-over effects. Sensitivity analysis was further conducted by examining epidemiological pre-trends, surveillance efforts, varying synthetic control matching characteristics and spill-over specifications. We demonstrate that our estimates are not due to pre-existing epidemiological trends, surveillance efforts, and/or preventive policies. These estimates highlight the potential of mass gatherings in one region to spill-over into an outbreak of national scale. Relaxations of mass gathering restrictions must therefore be carefully considered, even in the context of low community transmission and enforcement of safe distancing guidelines.

Polylactic acid (PLA) is a promising biodegradable polyester, however, the brittle nature of PLA restricts its applications. In this study, PLA is reinforced by artificially cultured diatom frustules (DFs) to prepare high-performance and biodegradable polymer composites via melt blending. Interpenetrating structure can be observed between DFs and PLA by scanning electron microscope (SEM) due to the porous nature of diatom. Both X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis reveal that well-dispersed DFs can act as a nucleating agent to increase the crystallinity of the α-crystal in PLA, but decrease its cold crystallization temperature (Tcc). Tensile tests show that both strength and ductility of PLA can be enhanced simultaneously by incorporation of a few percent of DFs. Dynamic mechanical analysis (DMA) indicates that DFs can increase the storage modulus and maintain the glass transition temperature of PLA. Our study illustrates the promise of utilizing artificially cultured diatom frustules as biomass-based reinforcing fillers for preparing high-performance fully-biodegraded polymeric materials for green and sustainable applications.

Background: With at least 94 countries undergoing or exiting lockdowns for contact suppression to control the COVID-19 outbreak, sustainable and public health-driven exit strategies are required. Here we explore the impact of lockdown and exit strategies in Singapore for immediate planning. Methods: We use an agent-based model to examine the impacts of epidemic control over 480 days. A limited control baseline of case isolation and household member quarantining is used. We measure the impact of lockdown duration and start date on final infection attack sizes. We then apply a 3-month gradual exit strategy, immediately re-opening schools and easing workplace distancing measures, and compare this to long-term social distancing measures. Findings: At baseline, we estimated 815 400 total infections (21.6% of the population). Early lockdown at 5 weeks with no exit strategy averted 18 500 (2.27% of baseline averted), 21 300 (2.61%) and 22 400 (2.75%) infections for 6, 8 and 9-week lockdown durations. Using the exit strategy averted a corresponding 114 700, 121 700 and 126 000 total cases, representing 12.07–13.06% of the total epidemic size under baseline. This diminishes to 9 900–11 300 for a late 8-week start time. Long-term social distancing at 6 and 8-week durations are viable but less effective. Interpretation: Gradual release exit strategies are critical to maintain epidemic suppression under a new normal. We present final infection attack sizes assuming the ongoing importation of cases, which require preparation for a potential second epidemic wave due to ongoing epidemics elsewhere. Funding: Singapore Ministry of Health, Singapore Population Health Improvement Centre.

Solar–thermal conversion and migration characteristics of nanofluids have attracted intensive attention recently. Due to the strong absorption of solar energy, solar collectors with nanofluids have wide applications in many areas including desalination and power generation. Researchers have mainly focused on the macroscopic performance of nanofluids in solar collectors, but the nanoparticles’ migration characteristics with vapor during phase transformation have not been further investigated. Therefore, an experimental investigation on solar–thermal conversion characteristics of nanofluids and migration characteristics with vapor during phase transformation was conducted in this work, in order to verify the enhancement effect of nanoparticles on solar energy absorption and explore the nanoparticles’ migration behavior with vapor. It was found that part of Ag nanoparticles migrate out of the nanofluids with generated vapor by boiling nanofluids, and most of the nanoparticles remained in the nanofluids. In addition, more Ag nanoparticles migrated with vapor with the increased heating power. The concentration of migrated nanofluids was 20.58 ppm with a power of 16.2 W and 31.39 ppm with a power of 20 W. The investigation pointed out the potential danger of nanofluids in the process of utility and provided a reference for the standardized application of nanofluids.

As low-cost, widely distributed and easily accessible renewable clean energy, solar energy has attracted more and more attention. Direct absorption solar collectors can convert solar energy into heat, but their efficiency is closely related to the absorption performance of the working fluid. In order to improve the absorption efficiency of direct absorption solar collectors, an experimental study on the selective absorption of solar energy by hybrid nanofluids was carried out. Five hybrid nanofluids were prepared and characterized, and the energy transfer advantages of hybrid nanofluid over single nanofluid were carefully studied. Experiments have found that the light-to-heat conversion properties of hybrid nanofluids show no obvious advantages or disadvantages compared with single nanofluid, and their performance is closely related to the types of nanoparticles. In addition, the hybrid nanofluid generally has two peaks, exactly the same as the single nanofluid in the mixed component, but the absorption curve is flatter than that of the single nanofluid. Further research of more types of hybrid nanofluids can provide new insights into the use of solar energy.

Mid-infrared (MIR) photonics are generating considerable interest because of the potential applications in spectroscopic sensing, thermal imaging, and remote sensing. Silicon photonics is believed to be a promising solution to realize MIR photonic integrated circuits (PICs). The past decade has seen a huge growth in MIR PIC building blocks. However, there is still a need for the development of MIR reconfigurable photonics to enable powerful on-chip optical systems and new functionalities. In this paper, we present an MIR (3.7~4.1 μm wavelength range) MEMS reconfiguration approach using the suspended silicon waveguide platform on the silicon-on-insulator. With the sub-wavelength grating claddings, the photonic waveguide can be well integrated with the MEMS actuator, thus offering low-loss, energy-efficient, and effective reconfiguration. We present a simulation study on the waveguide design and depict the MEMS-integration approach. Moreover, we experimentally report the suspended waveguide with propagation loss (−2.9 dB/cm) and bending loss (−0.076 dB each). The suspended waveguide coupler is experimentally investigated. In addition, we validate the proposed optical MEMS approach using a reconfigurable ring resonator design. In conclusion, we experimentally demonstrate the proposed waveguide platform’s capability for MIR MEMS-reconfigurable photonics, which empowers the MIR on-chip optical systems for various applications.

Zearalenone (ZEN) is a kind of nonsteroidal mycotoxin that is considered a risk affecting the safety of human food and livestock feed that causes oxidative damages in mammalian cells. Selenomethionine (SeMet) was indicated to have antioxidant activity and received great interest in investigating the role of SeMet as a therapeutic agent in oxidation. Therefore, the aim of this study was to investigate the hormetic role of DL-SeMet in porcine intestinal epithelial J2 (IPEC-J2) cells against ZEN-induced oxidative stress injury. As a result of this experiment, 30 μg/mL of ZEN was observed with significantly statistical effects in cell viability. Following the dose-dependent manner, 20 μg/mL was chosen for the subsequent experiments. Then, further results in the current study showed that the ZENinduced oxidative stress with subsequent suppression of the expression of antioxidant stress pathway-related genes species. Moreover, SeMet reversed the oxidative damage and cell death of ZEN toxins to some extent, by a Nrf2/Keap1-ARE pathway. The finding of this experiment provided a foundation for further research on the ZEN-caused cell oxidative damage and the cure technology.

Background: Agricultural expansion is a leading driver of deforestation, yet malnutrition remains a significant cause of morbidity. Understanding trade-offs and synergies between forest protection and agricultural expansion, and how they vary between groups across time, could help guide socially equitable sustainable development. Forests have important roles in supporting dietary diversity and micronutrient intake, but limited empirical evidence links forests and broad nutritional outcomes. Our research explores the associations between key indicators of malnutrition and forest cover and deforestation, the mediating role of socioeconomic factors, and underlying temporal trends. Methods: In this observational study, we explored associations between nutritional outcomes (underweightness, stunting, wasting, and overweightness) in children younger than 5 years and forest cover and loss gradients (in 10 km buffers around communities) in 61 032 African households. These households were surveyed by the Demographic and Health Surveys (DHS) Program from nine countries (Burkina Faso, Cameroon, Democratic Republic of the Congo, Ethiopia, Ghana, Guinea, Kenya, Lesotho, and Liberia) between 2003 and 2014. DHS data were combined with spatially explicit data on forest cover and loss, climate, infrastructure, economy, and demography in a series of generalised linear mixed-effects models. Findings: In urban areas, children in communities surrounded by 1 SD higher forest cover had 10·8% (95% CI 3·0–18·0; p=0·0073) lower incidence of underweightness and 11·7% (1·9–20·6; p=0·0212) lower incidence of wasting than did children in areas with the mean amount of forest cover. In rural areas, the relationship was reversed, with 6·0% (1·6–10·6; p=0·0074) higher incidence of underweightness among children in areas of 1 SD higher forest cover than among children in areas with the mean amount of forest cover. These relationships became marginally non-significant when analysing the urban and rural datasets together. Additionally, children in areas of 1 SD higher deforestation had 6·7% (1·4–12·3; p=0·0124) and 2·6% (0·04–5·2; p=0·0460) higher incidence of underweightness in urban and rural areas, respectively, than did children in areas with the mean amount of deforestation. This positive relationship between deforestation and underweightness appeared to diminish over time. Interpretation: Our results provide evidence that forest cover is associated with worse nutritional outcomes in rural areas, but better outcomes in urban areas of Africa. We did not explicitly measure the contribution of forests to dietary diversity. Yet, the nutritional trade-offs between rural African forests and agriculture should be assessed alongside potential micronutrient benefits from forest foods. Furthermore, forest loss appears to be associated with worse nutrition in the short term, although unmeasured frontier migration might have a role. These results might indicate a farm–forest frontier effect, with short-term declines in nutrition during deforestation events, potentially followed by long-term improvements, although further research is required to substantiate this hypothesis. These nutritional effects should be recognised and accounted for in efforts to meet sustainable development objectives relating to health and forest protection. Funding: Ministry of Education of Singapore.

Background: Potential synergies between public health and environmental protection that offer new opportunities for achieving health and sustainable development targets have been postulated. However, empirical evidence of the effect of ecosystem degradation and protection on public health outcomes is scarce, which restricts policy makers' ability to assess the net health effects of land-use change. Methods: We used generalised linear mixed-effects models to analyse data for 35 547 households in 1766 communities from the Cambodian Demographic Health Surveys to investigate the relation between health and protected areas across deforestation gradients in Cambodia between Feb 1, 2005, and April 30, 2014. Diarrhoea, acute respiratory infection, and fever in children younger than 5 years were used as population health indicators. Dense and mixed forest coverage were derived from Open Development Cambodia, and forest loss was calculated from 2000 to 2004, 2004 to 2009, and 2009 to 2014. The incidence of non-specific illness and injury in people older than 15 years was used as a negative control. Our analyses included rich pseudo-panel data (combining cross-sectional datasets from 2005, 2010, and 2014) that accounted for socioeconomic, demographic, and behavioural characteristics, and had a negative control, approximating a quasi-experimental study design. Findings: Deforestation of dense forest was associated with an increased incidence of diarrhoea (p=0·007), fever (p=0·0495), and acute respiratory infection in children (p=0·003). For example, a 10 percentage point increase in loss of dense forest was estimated to be associated with an increase of 14·1% (95% CI 2·6–35·8) in the incidence of diarrhoea in children younger than 5 years per household in the 2 weeks before the Cambodian Demographic Health Surveys. Protected area coverage, but not type, was associated with decreased incidences of diarrhoea (p=0·028) and acute respiratory infection (p=0·030). Apart from an association between mixed forest coverage and increased incidence of diarrhoea, forest coverage was not associated with any health outcomes. Interpretation: Deforestation is associated with increased risk of several major sources of global childhood morbidity and mortality. Although causal mechanisms are unclear, our findings suggest that protected areas could help to alleviate the global health burden, presenting new possibilities for simultaneous achievement of public health and conservation goals. Funding: Ministry of Education of Singapore.