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Efficient photosynthesis requires a balance of ATP and NADPH production/consumption in chloroplasts, and the exportation of reducing equivalents from chloroplasts is important for balancing stromal ATP/NADPH ratio. Here, we showed that the overexpression of purple acid phosphatase 2 on the outer membranes of chloroplasts and mitochondria can streamline the production and consumption of reducing equivalents in these two organelles, respectively. A higher capacity of consumption of reducing equivalents in mitochondria can indirectly help chloroplasts to balance the ATP/NADPH ratio in stroma and recycle NADP+, the electron acceptors of the linear electron flow (LEF). A higher rate of ATP and NADPH production from the LEF, a higher capacity of carbon fixation by the Calvin–Benson–Bassham (CBB) cycle and a greater consumption of NADH in mitochondria enhance photosynthesis in the chloroplasts, ATP production in the mitochondria and sucrose synthesis in the cytosol and eventually boost plant growth and seed yields in the overexpression lines.
The Dayao Paleolithic site, located in Inner Mongolia on the eastern margin of China's vast northwestern drylands, was a lithic quarry-workshop utilized by Pleistocene human migrants through the region. Determining the age of this activity has previously yielded controversial results. Our magnetostratigraphic and OSL dating results suggest the two artifact-bearing paleosols are correlated with MIS 5 and 7, respectively. Correlating paleoclimatic data with marine δ18O records leads us to conclude that two sandy gravel layers containing many artifacts in the lower part of the Dayao sequence were formed during MIS 9 and 11, if not earlier. Our results reveal that the earliest human occupation at the Dayao site occurred before ca. 400 ka during a relatively warm and moist interglacial period, similar to several subsequent occupations, documenting the earliest and northernmost archaeological assemblage yet reported in China's arid northwest. We conclude that the northward and southward displacements of the East Asian summer monsoon rain belt during past interglacial-glacial cycles were responsible for the discontinuous human occupation detected at the Dayao site. The penetration of this precipitation regime into dryland ecologies via the Huanghe (Yellow River) Valley effectively created a corridor for hominin migration into China's arid northwest.
Over recent decades, Chinese giant salamanders Andrias spp. have declined dramatically across much of their range. Overexploitation and habitat degradation have been widely cited as the cause of these declines. To investigate the relative contribution of each of these factors in driving the declines, we carried out standardized ecological and questionnaire surveys at 98 sites across the range of giant salamanders in China. We did not find any statistically significant differences between water parameters (temperature, dissolved oxygen, ammonia, nitrite, nitrate, salinity, alkalinity, hardness and flow rate) recorded at sites where giant salamanders were detected by survey teams and/or had been recently seen by local respondents, and sites where they were not detected and/or from which they had recently been extirpated. Additionally, we found direct and indirect evidence that the extraction of giant salamanders from the wild is ongoing, including within protected areas. Our results support the hypothesis that the decline of giant salamanders across China has been primarily driven by overexploitation. Data on water parameters may be informative for the establishment of conservation breeding programmes, an initiative recommended for the conservation of these species.
A multidisciplinary fieldwork and research project was recently begun at the Yangshang site (220–140 ka), a late Early Paleolithic locale in the western Chinese Loess Plateau. 1696 lithic artifacts and 337 faunal remains were recovered during the excavation. Sedimentological and paleoenvironmental investigations indicate the site preserves a relatively long and minimally disturbed archaeological sequence associated with paleoenvironmental changes during MIS 7–6. A detailed techno-typological analysis of Yangshang's lithic assemblages was undertaken to examine the influence of glacial cycles on late Middle Pleistocene hominin technological strategies in the western Chinese Loess Plateau. The results show that while the Yangshang site is dominated by quartz-based core/flake assemblages typical of most Early Paleolithic sites in North China, the lithic assemblages provide evidence that different provisioning systems existed during the penultimate glaciation. We argue that these shifts reflect changes in land use and mobility that were tied to climate change. Our results suggest that theoretically informed statistical analyses of so-called unchanging and crude lithic technology can yield meaningful evidence for behavioral shifts.
Modern electron microscopy permits scientists to study the fine detail of cells and tissues, using both two-dimensional and three-dimensional imaging modalities. However, achieving optimal preservation of ultrastructure for a variety of biological samples remains a challenge. Here, we describe practical methods to preserve the fine structure of mouse skeletal muscle and sciatic nerve and to obtain high-resolution images of mitochondria in cultured cells, flow-sorted T-cells, and mouse urothelium. We also propose an effective and economical workflow for three-dimensional electron microscopy in the context of a microscopy core facility.
The neuropeptide oxytocin is proposed as a promising therapy for social dysfunction by modulating amygdala-mediated social-emotional behavior. Although clinical trials report some benefits of chronic treatment, it is unclear whether efficacy may be influenced by dose frequency or genotype.
In a randomized, double-blind, placebo-controlled pharmaco-functional magnetic resonance imaging trial (150 male subjects), we investigated acute and different chronic (every day or on alternate days for 5 days) intranasal oxytocin (24 international units) effects and oxytocin receptor genotype-mediated treatment sensitivity on amygdala responses to face emotions. We also investigated similar effects on resting-state functional connectivity between the amygdala and prefrontal cortex.
A single dose of oxytocin-reduced amygdala responses to all face emotions but for threatening (fear and anger) and happy faces, this effect was abolished after daily doses for 5 days but maintained by doses given every other day. The latter dose regime also enhanced associated anxious-arousal attenuation for fear faces. Oxytocin effects on reducing amygdala responses to face emotions only occurred in AA homozygotes of rs53576 and A carriers of rs2254298. The effects of oxytocin on resting-state functional connectivity were not influenced by either dose-frequency or receptor genotype.
Infrequent chronic oxytocin administration may be therapeutically most efficient and its anxiolytic neural and behavioral actions are highly genotype-dependent in males.
In this paper, the generation of relativistic electron mirrors (REMs) and the reflection of an ultra-short laser off this mirrors are discussed, applying two-dimensional particle-in-cell (2D-PIC) simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapidly expanding. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads the resonance between laser and REM. The reflected radiation near this interval and the corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, certain part of the reflected field could be selectively amplified or depressed, leading to the selectively adjusting of the corresponding spectra.
Health behavior was conducive to control the coronavirus disease (COVID-19) epidemic. This study aimed to determine the differences in health behaviors and related factors among rural and urban residents in China.
From February 14 to 22, 2020, during the peak of the COVID-19 epidemic in China, a total of 2449 participants (1783 (72.81%) urban residents and 666 (27.19%) rural residents) were recruited by snowball sampling on WeChat and QQ social platforms, both owned by Tencent. Data were collected through the Web-questionnaire guided by an information–motivation–behavioral skills model. The multiple-group structural equation model was applied to analyze the factors.
Rural residents had lower health behavior scores than urban residents, even after adjusting demographic characteristics (33.86 vs 34.29, P = 0.042; total score was 40). Motivational, behavioral skills, and stress had direct positive and negative influences on health behaviors of urban and rural residents. Information and positive perception of interventions had direct effects on health behaviors in rural residents, but not in urban residents. All the factors were mediated by behavioral skills in rural and urban residents.
This study suggests that the government should pay attention to substantial rural and urban disparities and implement different COVID-19 prevention and intervention policies for health behaviors targeting rural and urban residents.
Reward dysfunction is a major dimension of depressive symptomatology, but it remains obscure if that dysfunction varies across different reward types. In this study, we focus on the abnormalities in anticipatory/consummatory processing of monetary and social reward associated with depressive symptoms.
Forty participants with depressive symptoms and forty normal controls completed the monetary incentive delay (MID) and social incentive delay (SID) tasks with event-related potential (ERP) recording.
In the SID but not the MID task, both the behavioral hit rate and the ERP component contingent negative variation (CNV; indicating reward anticipation) were sensitive to the interaction between the grouping factor and reward magnitude; that is, the depressive group showed a lower hit rate and a smaller CNV to large-magnitude (but not small-magnitude) social reward cues compared to the control group. Further, these two indexes were correlated with each other. Meanwhile, the ERP components feedback-related negativity and P3 (indicating reward consumption) were sensitive to the main effect of depression across the MID and SID tasks, though this effect was more prominent in the SID task.
Overall, we suggest that depressive symptoms are associated with deficits in both the reward anticipation and reward consumption stages, particularly for social rewards. These findings have a potential to characterize the profile of functional impairment that comprises and maintains depression.
The present study aimed to investigate the association of the Chinese visceral adiposity index (CVAI) and its 6-year change with hypertension risk and compare the ability of CVAI and other obesity indices to predict hypertension based on the Rural Chinese Cohort Study. Study participants were randomly recruited by a cluster sampling procedure, and 10 304 participants ≥18 years were included. Modified Poisson regression was used to derive adjusted relative risks (RR) and 95 % CI. We identified 2072 hypertension cases during a median of 6·03 years of follow-up. The RR for the highest v. lowest CVAI quartile were 1·29 (95 % CI 1·05, 1·59) for men and 1·53 (95 % CI 1·22, 1·91) for women. Per-sd increase in CVAI was associated with hypertension for both men (RR 1·09, 95 % CI 1·02, 1·16) and women (RR 1·14, 95 % CI 1·06, 1·22). Also, the area under the receiver operating characteristic curve value for hypertension was higher for CVAI than the four other obesity indices for both sexes (all P < 0·05). Finally, per-sd increase in CVAI change was associated with hypertension for both men (RR 1·26, 95 % CI 1·16, 1·36) and women (RR 1·23, 95 % CI 1·15, 1·30). Similar results were observed in sensitivity analyses. CVAI and its 6-year change are positively associated with hypertension risk. CVAI has better performance in predicting hypertension than other visceral obesity indices for both sexes. The current findings suggest CVAI as a reliable and applicable predictor of hypertension in rural Chinese adults.
The cellular accumulation of drug delivery systems (DDSs) is a critical parameter to determine the final outcome of cancer chemotherapy. Herein, we designed a red blood cells membrane-based vehicle (RV) and employed it to load both doxorubicin (Dox) and IR 780 (RV/I-D). The photothermal-assisted chemotherapy efficacy of RV/I-D on the treatment of cancer was tested on a prostate cancer model. Excitingly, the results showed that RV/I-D was stable and safe nanoparticles with size at about 100 nm. Moreover, upon the increase of system temperature using photothermal effects of IR780, the drug release of the DDS was accelerated. Above all, the DDS also increased the accumulation of drugs into the Dox-resistant prostate cancer cells (PC-3/Dox) both in vitro and in vivo and showed enhanced anticancer performance.
Iridium (Ir) has an extremely high melting point (2443 °C), high chemical stability and is one of the most promising high-temperature materials. However, Ir is more difficult to process compared with other face-centered cubic metals, such as Ni and Al, which limits its applications. To solve this problem, we study the effect of 32 alloying elements (X) on stacking fault energy of dilute Ir-based alloys generated by shear deformation using the first-principles calculations. The investigation reveals that there are many alloying elements studied herein decrease the stacking fault energy of face-centered cubic (fcc) Ir, and the most effective element in reducing stacking fault energy of fcc Ir is Zn. The microscopic mechanism is caused by electron redistribution in the local stacking fault area. These results are expected to provide valuable guidance for the further design and application of Ir-based alloys.
Early life stress has been associated with emotional dysregulations and altered architecture of limbic-prefrontal brain systems engaged in emotional processing. Serotonin regulates both, developmental and experience-dependent neuroplasticity in these circuits. Central serotonergic biosynthesis rates are regulated by Tryptophan hydroxylase 2 (TPH2) and transgenic animal models suggest that TPH2-gene associated differences in serotonergic signaling mediate the impact of aversive early life experiences on a phenotype characterized by anxious avoidance.
The present study employed an imaging genetics approach that capitalized on individual differences in a TPH2 polymorphism (703G/T; rs4570625) to determine whether differences in serotonergic signaling modulate the effects of early life stress on brain structure and function and punishment sensitivity in humans (n = 252).
Higher maltreatment exposure before the age of 16 was associated with increased gray matter volumes in a circuitry spanning thalamic-limbic-prefrontal regions and decreased intrinsic communication in limbic-prefrontal circuits selectively in TT carriers. In an independent replication sample, associations between higher early life stress and increased frontal volumes in TT carriers were confirmed. On the phenotype level, the genotype moderated the association between higher early life stress exposure and higher punishment sensitivity. In TT carriers, the association between higher early life stress exposure and punishment sensitivity was critically mediated by increased thalamic-limbic-prefrontal volumes.
The present findings suggest that early life stress shapes the neural organization of the limbic-prefrontal circuits in interaction with individual variations in the TPH2 gene to promote a phenotype characterized by facilitated threat avoidance, thus promoting early adaptation to an adverse environment.
In the current research, a 60-d experiment was conducted with the purpose of exploring the impacts of methionine (Met) on growth performance, muscle nutritive deposition, muscle fibre growth and type I collagen synthesis as well as the related signalling pathway. Six diets (iso-nitrogenous) differing in Met concentrations (2·54, 4·85, 7·43, 10·12, 12·40 and 15·11 g/kg diets) were fed to 540 grass carp (178·47 (SD 0·36) g). Results showed (P < 0·05) that compared with Met deficiency, optimal level of dietary Met (1) increased feed intake, feed efficiency, specific growth rate and percentage weight gain (PWG); (2) increased fish muscle protein, lipid and free amino acid contents and improved fish muscle fatty acid profile as well as increased protein content in part associated with the target of rapamycin complex 1 (TORC1)/S6K1 signalling pathway; (3) increased the frequency distribution of muscle fibre with >50 µm of diameter; (4) increased type I collagen synthesis partly related to the transforming growth factor-β1/Smads and CK2/TORC1 signalling pathways. In conclusion, dietary Met improved muscle growth, which might be due to the regulation of muscle nutritive deposition, muscle fibre growth and type I collagen synthesis-related signal molecules. Finally, according to PWG and muscle collagen content, the Met requirements for on-growing grass carp (178–626 g) were estimated to be 9·56 g/kg diet (33·26 g/kg protein of diet) and 9·28 g/kg diet (32·29 g/kg of dietary protein), respectively.
HfO2–Sm3TaO7 ceramics are prepared through a solid-state reaction method. The X-ray diffraction and structural refinement show that the phase structures of HfO2–Sm3TaO7 ceramics are an ordered orthorhombic phase and the space groups are belonging to Ccmm. The degree of the structural disorder increases with increasing HfO2 content. The solid solution mechanism reveals that Hf4+ exists in the form of interstitial ions that cause crystal expansion when the doping content is less than 4 mol%. When the doping concentration of HfO2 ≥ 4 mol%, the Hf4+ ions can substitute an equal number of Sm3+ and Ta5+ ions. The phase transition of Sm3TaO7 ceramics is removed with increasing HfO2 content, and the 8 mol% HfO2–Sm3TaO7 ceramics have a high thermal expansion coefficient of 10.2 × 10−6 K−1 at 1200 °C. The 2 mol% HfO2–Sm3TaO7 ceramics have the lowest thermal conductivity (1.03 W/m K at 900 °C), which is lower than previous research of the 7–8 YSZ. The outstanding thermophysical properties of HfO2–Sm3TaO7 ceramics indicate that they are potential thermal-barrier coating materials.
In this research communication, a cell model with elevated β-CASEIN synthesis was established by stimulating bovine mammary epithelial cells with 0.6 mM methionine, and the genome-wide gene expression profiles of methionine-stimulated cells and untreated cells were investigated by RNA sequencing. A total of 458 differentially expressed genes (DEGs; 219 upregulated and 239 downregulated) were identified between the two groups. Gene Ontology (GO) analysis showed that the two highest-ranked GO terms in ‘molecular function’ category were ‘binding’ and ‘catalytic activity’, suggesting that milk protein synthesis in methionine-stimulated cells requires induction of gene expression to increase metabolic activity. Kyoto Encyclopedia of Genes and Genomes analysis revealed that within the ‘environmental information processing’ category, the subcategory that is most highly enriched for DEGs was ‘signal transduction’. cGMP-PKG, Rap1, calcium, cAMP, PI3K-AKT, MAPK, and JAK-STAT are the pathways with the highest number of DEGs, suggesting that these signaling pathways have potential roles in mediating methionine-induced milk protein synthesis in bovine mammary epithelial cells. This study provides valuable insights into the physiological and metabolic adaptations in cells stimulated with methionine. Understanding the regulation of this transition is essential for effective intervention in the lactation process.
To explore the association between dietary Na intake and non-alcoholic fatty liver disease (NAFLD) in a nationally representative sample of the US population.
In this cross-sectional study, the associations between Na intake and NAFLD, defined by the hepatic steatosis index (HSI) and the fatty liver index (FLI), were assessed through multivariable logistic regression models.
Communities in the USA from 2007 to 2014.
Men and women aged 20 years and older.
A total of 11 022 participants were included in the HSI-defined NAFLD analysis, and a subsample of 5320 participants was included in the FLI-defined NAFLD analysis. Compared with the lowest quartile of Na intake, the highest quartile had a multivariate-adjusted OR and 95 % CI of 1·46 (1·29, 1·65) for NAFLD as defined by HSI, and 1·41 (1·18, 1·69) for NAFLD as defined by FLI. This association was, to some degree, attenuated but remained significant after adjusting for several related metabolic parameters, including BMI, hypertension, hypercholesterolaemia, and diabetes.
Findings from the current study indicate that dietary Na intake is positively associated with NAFLD in US adults.
Since the first report of the 2019 novel coronavirus disease (COVID-19) in December 2019 in Wuhan, China, the outbreak of the disease has been continuously evolving. Until March 17, 2020, 185, 178 cases had been confirmed, including 81,134 cases in China and 104,044 cases outside of China. In this comment, we report the unexpected beneficial effect of a deployable rapid-assembly shelter hospital on the prevention and treatment of COVID-19. We describe the shelter hospital maintenance, treatment mode and primary treatment methods, which will provide a valuable experience in dealing with public health emergencies, such as COVID-19, for other countries and areas.