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Persistent humid climate favored the Qin and Western Han Dynasties in China around 2,200 y ago
The Qin and Western Han dynasties (221 BCE to 24 CE) represent an era of societal prosperity in China. However, due to a lack of high-resolution paleoclimate records it is still unclear whether the agricultural boost documented for this period was associated with more favorable climatic conditions. Here, multiparameter analysis of annually resolved tree-ring records and process-based physiological modeling provide evidence of stable and consistently humid climatic conditions during 270 to 77 BCE in northern China. Precipitation in the Asian summer monsoon region during the Qin–Western Han Dynasties was ~18 to 34% higher compared to present-day conditions. In shifting agricultural and pastoral boundaries ~60 to 100 km northwestward, possibility up to 200 km at times, persistently wetter conditions arguably increased food production, contributing to the socioeconomic prosperity around 2,200 y ago. A gradual wetting trend in the western part of arid northwestern China since the 1980s resembles the historical climate analogue, suggesting that similar benefits for regional environmental and agricultural systems may reoccur under current climate change, at least in the near term.
The effect of CO <sub>2</sub> ramping rate on the transient weakening of the Atlantic Meridional Overturning Circulation
The Atlantic Meridional Overturning Circulation (AMOC) is a key component of the global climate that is projected to weaken under future anthropogenic climate change. While many studies have investigated the AMOC’s response to different levels and types of forcing in climate models, relatively little attention has been paid to the AMOC’s sensitivity to the rate of forcing change, despite it also being highly uncertain in future emissions scenarios. In this study, I isolate the AMOC’s response to different rates of CO 2 increase in a state-of-the-art global climate model and find that the AMOC undergoes more severe weakening under faster rates of CO 2 change, even when the magnitude of CO 2 change is the same. I then propose an AMOC-ocean heat transport-sea ice feedback that enhances the decline of the circulation and explains the dependence on the rate of forcing change. The AMOC’s rate-sensitive behavior leads to qualitatively different climates (including differing Arctic sea ice evolution) at the same CO 2 concentration, highlighting how the rate of forcing change is itself a key driver of global climatic change.
Aerosol light absorption alleviates particulate pollution during wintertime haze events
Aerosol light absorption has been widely considered as a contributing factor to the worsening of particulate pollution in large urban areas, primarily through its role in stabilizing the planetary boundary layer (PBL). Here, we report that absorption-dominated aerosol–radiation interaction can decrease near-surface fine particulate matter concentrations ([PM 2.5 ]) at a large-scale during wintertime haze events. A “warm bubble” effect by the significant heating rate of absorbing aerosols above the PBL top generates a secondary circulation, enhancing the upward motion (downward motion) and the convergence (divergence) in polluted (relatively clean) areas, with a net effect of lowering near-surface [PM 2.5 ]. Furthermore, aerosol absorption of ultraviolet-wave light effectively reduces the photolysis of chemical species, i.e., aerosol–photolysis interaction, hindering ozone formation, reducing atmospheric oxidizing capability, and suppressing secondary aerosol concentrations. Our model assessment reveals that the synergetic two effects decrease near-surface [PM 2.5 ] by around 7.4%, so the presence of light-absorbing aerosols can considerably alleviate particulate pollution during wintertime haze events. Such negative feedbacks to the aerosol loading should be considered in weather/climate prediction and health assessment models.
Divergence time and environmental similarity predict the strength of morphological convergence in stick and leaf insects
Independent evolution of similar traits in lineages inhabiting similar environments (convergent or repeated evolution) is often taken as evidence for adaptation by natural selection, and used to illustrate the predictability of evolution. Yet convergence is rarely perfect for two reasons. First, environments may not be as similar as they appear. Second, responses to selection are contingent upon available genetic variation and independent lineages may differ in the alleles, genetic backgrounds, and even the developmental mechanisms responsible for the phenotypes in question. Both impediments to convergence are predicted to increase as the length of time separating two lineages increases, making it difficult to discern their relative importance. We quantified environmental similarity and the extent of convergence to show how habitat and divergence time each contribute to observed patterns of morphological evolution in 212 species of stick and leaf insects (order Phasmatodea). Dozens of phasmid lineages independently colonized similar habitats, repeatedly evolving in parallel directions on a 23-trait morphospace, though the magnitude and direction of these shifts varied. Lineages converging toward more similar environments ended up closer on the morphospace, as did closely related lineages, and closely related lineages followed more parallel evolutionary trajectories to arrive there than more distantly related ones. Remarkably, after accounting for habitat similarity, we show that divergence time reduced the extent of convergence at a constant rate across more than 100 My of separation, suggesting even the magnitude of contingency can be predictable, given sufficient spans of time.
The effect of job loss on risky financial decision-making
Job loss is a common and disruptive life event. It is known to have numerous long-term negative effects on financial, health, and social outcomes. While the negative effects of becoming unemployed on health and well-being are well understood, the influence of job loss on financial decisions has received little attention. Across a large-scale survey ( N = 37 , 854 ), spending data from a bank ( N = 404 , 470 ), and two online experiments (total N = 1 , 403 ), we find that job loss increases financial risk-taking. First, in survey data, job loss is associated with elevated levels of self-reported financial risk-taking and lottery ticket purchases. Next, using administrative data from a large bank, we find consistent causal evidence of the influence of job loss on gambling spending. Although total spending decreases after job loss, gambling spending is less affected than our control categories. Finally, we turn to two incentive-compatible manipulations of job loss operationalized in a lab setting. We find that this experimental manipulation increases the take-up of financial risks. The current finding that job loss increases financial risk-taking could accentuate long-term negative financial effects of job loss.
Fast-chargeable lithium-ion batteries by μ-Si anode-tailored full-cell design
Silicon (Si) anodes have long been recognized to significantly improve the energy density and fast-charging capability of lithium-ion batteries (LIBs). However, the implementation of these anodes in commercial LIB cells has progressed incrementally due to the immense volume change of Si across its full state-of-charge (SOC) range. Here, we report an anode-tailored full-cell design (ATFD), which incorporates micrometer-sized silicon (μ-Si) alone, for operation over a limited, prespecified SOC range identified as 30−70%. This range allows homogeneous (de)lithiation throughout the electrode, accompanied by an acceptable level of volume change. The ATFD-based cell exhibits 21.3% higher gravimetric energy density than that of its graphite-based counterpart in a commercial 18650 cylindrical cell and 84.6% capacity retention after 500 cycles even at a fast-charging rate of 3 C. This study indicates that the partial, intermediate SOC operation of the μ-Si anode can markedly increase the energy density and boost the fast-charging capability of a LIB cell, a challenging task in traditional cell engineering.
Personality differences between birth order categories and across sibship sizes
We examined associations of self-reports on the HEXACO Personality Inventory—Revised (HEXACO-PI-R) with birth order category and sibship size, controlling for participant sex and age. In a first sample ( N > 700,000 online adults, mainly from English-speaking countries), Honesty-Humility and Agreeableness both showed the highest means for middle-borns, followed in order by last-borns (youngests), firstborns (oldests), and only children, with differences between middles and onlys of d ≥ 0.20. The same result was replicated in a similar but smaller second sample ( N > 70,000) in which sibship size was also assessed, thereby allowing birth order differences to be separated from sibship size differences. In that sample, Honesty-Humility and Agreeableness showed higher means with larger sibship sizes, with differences between sibship sizes of 1 and 6+ of d = 0.30 and d = 0.36, respectively. Controls for upbringing religiousness and current religiousness reduced these differences by about 25%. Within sibship sizes, birth order differences in these dimensions were considerably smaller but oldests remained up to d = 0.10 lower than middles and youngests. Openness was d ≈ 0.10 higher for onlys than for non-onlys collectively, and within sibship sizes, Openness was d ≈ 0.10 higher for oldests than for middles and youngests.
Correction for Ritz et al., Social anxiety disorder-associated gut microbiota increases social fear
Correction for Bartesaghi et al., Inhibition of oxidative metabolism leads to p53 genetic inactivation and transformation in neural stem cells
Correction for Armstrong et al., Genetic differentiation and precolonial Indigenous cultivation of hazelnut ( <i>Corylus cornuta</i> , Betulaceae) in western North America
Correction for Yun et al., GPCR targeting of E3 ubiquitin ligase MDM2 by inactive β-arrestin
Correction for Zhou et al., A genome-wide microRNA screen identifies the microRNA-183/96/182 cluster as a modulator of circadian rhythms
Correction for Huo et al., Hierarchical behavior control by a single class of interneurons
Nocturnal camouflage through background matching against moonlight
Camouflage is often considered a daytime phenomenon based on light and shade. Nocturnal camouflage can also occur, but its mechanistic basis remains unclear. Here, we analyze the conditions for background matching (BM) of avian predators against the night sky. Such concealment is achieved when the contrast between the predator and the sky is smaller than the contrast detection threshold of prey. This condition cannot be fulfilled under isotropic skies, as in fully overcast or moonless nights. However, on clear moonlit nights, the isotropy of the sky radiance is broken due to the presence of the Moon, and the conditions for BM can be met for a wide range of sky directions. This effect is mainly dependent on the altitude of the Moon above the horizon, rather than on Moon phase. We have modeled the feasibility of concealment through BM of a typically white barn owl ( Tyto alba ) when hunting rodents, based on its contrast against the moonlit sky. We considered the radiometric quantities of the sky, the ground, and the bird’s undersides. Our results show that a barn owl with highly reflecting underparts may approach a rodent from broad regions of the moonlit sky while keeping itself below the contrast detection threshold of the mouse M-cones and rods. S-cones, in turn, remain below their excitation threshold for most of the lunar cycle. Our results demonstrate that the white color of barn owls serves as camouflage tailored to the moonlit sky background, providing a mechanistic basis for understanding nocturnal camouflage.
Mitochondrial DNA lineages determine tumor progression through T cell reactive oxygen signaling
Mitochondrial DNA (mtDNA) is highly polymorphic, and host mtDNA variation has been associated with altered cancer severity. To determine the basis of this mtDNA–cancer association, we analyzed conplastic mice with the C57BL/6J (B6) nucleus but two naturally occurring mtDNA lineages, mtDNA B6 and mtDNA NZB , where mtDNA NZB mitochondria generate more oxidative phosphorylation (OXPHOS)-derived reactive oxygen species (mROS). In a cardiac transplant model, mtDNA B6 Foxp3+ T regulatory (Treg) cells supported long-term allograft survival, whereas mtDNA NZB Treg cells failed to suppress host T effector (Teff) cells, leading to acute rejection. When challenged with melanoma or colon cancer cells, the mtDNA NZB mice exhibited strikingly impaired tumor growth while mtDNA B6 mice showed Treg-dependent inhibition of Teff cells and allowed rapid tumor growth. Transcriptional analysis showed that activation of mtDNA NZB Teff cells increased mitochondrial gene expression while activation of mtDNA NZB Treg cells impaired mitochondrial gene expression and resulted in mtDNA NZB Treg cell exhaustion. Induction of the mitochondrially targeted catalytic antioxidant, mCAT, in hematopoietic cells normalized mtDNA NZB Treg function in both transplant and tumor models, indicating a key role for mROS in promoting Treg dysfunction. Anti-PD-L1 therapy did not modulate these effects, indicating that modulation of host mitochondrial function provides an independent approach for enhancing tumor cell destruction.
Changing patterns of general practice services during a period of public sector investment in Britain
Introduction Given the importance of GP care to the public’s health, it is important that we understand how patterns of service use change as levels of investment change. This study investigated GP use in Britain in conjunction with use of outpatient services during a period of investment and during a period of austerity. Method The study used data from the British Household Panel Survey (BHPS) that included service use, morbidity (as an indicator of need) and socio-demographic characteristics (e.g., employment, age, education, and sex). Data for 2000, 2004, and 2008, were specifically chosen for comparison with data from 2015, 2016 and 2017. Service use and respondent characteristics were described using measures of central tendency and dispersion. Multivariable analyses were undertaken using recursive bivariate probit (RBVP) and probit analyses separately for each study year. All analyses were adjusted for cross-sectional weighting. Results BHPS respondents who used outpatient services or GP services had higher morbidity compared to survey participants who did not. Older people, people with lower educational attainment and employed people had higher mean morbidity indices in each study year as did females. Morbidity among service users tended to decline slightly over time. RBVP analyses revealed a significant positive correlation in residuals between outpatient and GP functions in 2000 and 2004 but not 2008. GP consultations and outpatient use remained largely unrelated to socio-economic factors in each year. Survey participants who reported hearing or vision impairment conditions were consistently less likely to use GP or outpatient services in 2000 and 2004, in 2008. Conclusion The results are broadly indicative of stable relationships in service use during a period of healthcare investment but change during austerity. Those who reported, vision, hearing, and skin conditions were consistently less likely to report use of GP or outpatient services, controlling for other aspects of health.
Association between serum uric acid, hyperuricemia and low muscle mass in middle-aged and elderly adults: A national health and nutrition examination study
Backgrounds Recent research suggests that uric acid, as a metabolite with antioxidant properties, may affect muscle function and health. However, the association between serum uric acid (SUA) and low muscle mass remains relatively obscure. This study focuses on the association between SUA and low muscle mass in a middle-aged and elderly population in the United States. Methods Utilizing data from the National Health and Nutrition Examination Survey (NHANES), a total of 12,106 patients aged ≥45 years, possessing complete analytical data, were incorporated. Low muscle mass in our study is defined as indices below 0.789 for males and 0.512 for females, according to the FNIH Biomarkers Consortium. Gender stratified analyses were conducted employing a multivariate weighted logistic regression model. When examining serum uric acid (SUA) levels, the SUA dataset was stratified into deciles, and odds ratios (ORs) were calculated across distinct subgroups of males and females. A restricted cubic spline (RCS) method was employed to investigate the potential nonlinear association between SUA levels and low muscle mass. A series of subgroup analyses stratified by demographic variables and clinical experience were conducted. Results A total of 2,185 participants (18.05%) were identified with low muscle mass, comprising 1,121 males and 1,064 females. Females with low muscle mass had higher SUA levels and an increased incidence of hyperuricemia compared to those without low muscle mass. In females, a fully adjusted multivariable weighted regression model revealed a positive association between hyperuricemia and low muscle mass (OR, 1.43; 95% CI, 1.06 to 1.92; P = 0.021). No significant association was observed in males. Additionally, RCS curves indicated a J-shaped relationship between increasing SUA levels and the risk of low muscle mass in females, and an inverse J-shaped relationship in males. Conclusions This study reveals a significant positive correlation between hyperuricemia and the risk of low muscle mass in middle-aged and older women in the United States, whereas the relationship between SUA levels and low muscle mass did not attain statistical significance. In the male cohort, neither SUA levels nor hyperuricemia demonstrated a significant association with low muscle mass.
Human brain dynamics are shaped by rare long-range connections over and above cortical geometry
A fundamental topological principle is that the container always shapes the content. In neuroscience, this translates into how the brain anatomy shapes brain dynamics. From neuroanatomy, the topology of the mammalian brain can be approximated by local connectivity, accurately described by an exponential distance rule (EDR). The compact, folded geometry of the cortex is shaped by this local connectivity, and the geometric harmonic modes can reconstruct much of the functional dynamics. However, this ignores the fundamental role of the rare long-range (LR) cortical connections, crucial for improving information processing in the mammalian brain, but not captured by local cortical folding and geometry. Here, we show the superiority of harmonic modes combining rare LR connectivity with EDR (EDR+LR) in capturing functional dynamics (specifically LR functional connectivity and task-evoked brain activity) compared to geometry and EDR representations. Importantly, the orchestration of dynamics is carried out by a more efficient manifold made up of a low number of fundamental EDR+LR modes. Our results show the importance of rare LR connectivity for capturing the complexity of functional brain activity through a low-dimensional manifold shaped by fundamental EDR+LR modes.
Child welfare worker perspectives on documentation and case recording practices in Canada: A mixed-methods study protocol
In health care and child welfare, clinical records and case notes serve multiple functions. When records are aggregated and processed to create administrative data, they can be analyzed and used to inform policy development and decision-making. To be useful, such data should be complete, accurate, and recorded in a standardized way. However, sources of bias and error can impact the quality of administrative data. During the development of national child welfare data in Canada, child welfare sector partners expressed concerns about the accuracy and completeness of data about children and families. This protocol describes a study that seeks to answer two questions: 1) What individual and institutional factors influence how client data is recorded by child welfare workers in Canada? 2) What data quality issues are created through documentation and case recording practices that may impact the use of clinical case management system data for public health statistics? In this protocol, we describe an exploratory mixed methods study that involves an online survey, interviews with a purposive sample of child welfare workers, and a document review of case recording guidelines. To be eligible for the study, participants must have worked at a child welfare agency or department with clinical documentation responsibilities as a part of their job. We will use descriptive statistics to analyze the survey data and thematic analysis to analyze the qualitative data. This study will help uncover strengths, limitations, and possible sources of bias created through case recording and documentation practices in child welfare. Study results will be shared through presentations to interest holders and will inform the further development of national child welfare data in Canada.