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Energy–poverty–inequality SDGs: A large-scale household analysis and forecasting in China

Affordable and clean energy, eliminating poverty, and reducing inequality are important goals of the United Nations Sustainable Development Goals (SDGs). This paper examines the role of access to clean cooking fuels in promoting income growth and reducing income inequality. Using data from Chinese households, we show that a 10% increase in the adoption of clean cooking fuels would result in an increase in total annual household income of US$37 billion nationwide. Income growth from access to clean cooking fuels is greater for lower-income groups due to a shift to higher household income and reduced downward household income mobility, which contributes to a reduction in income inequality. The effect of access to clean cooking fuels on household income growth is primarily driven by improved health and increased labor supply. The use of clean cooking fuels also saves fuel collection time and cooking time, reducing time spent on household chores by about 0.4 h per day, thereby increasing labor supply in the job market and improving wage income. Improvements in income due to clean cooking fuels are influenced by external conditions, urbanization, education, employment opportunities, and good market conditions. With further promotion of clean cooking fuels, household income and inequality in China are expected to improve further by 2030 and contribute more widely to human well-being and achievement of the SDGs.

The unequal adoption of ChatGPT exacerbates existing inequalities among workers

We study the adoption of ChatGPT, the icon of Generative AI, using a large-scale survey linked to comprehensive register data in Denmark. Surveying 18,000 workers from 11 exposed occupations, we document that ChatGPT is widespread, especially among younger and less-experienced workers. However, substantial inequalities have emerged. Women are 16 percentage points less likely to have used the tool for work. Furthermore, despite its potential to lift workers with less expertise, users of ChatGPT earned slightly more already before its arrival, even given their lower tenure. Workers see a substantial productivity potential in ChatGPT but are often hindered by employer restrictions and a perceived need for training.

Gonadal sex and temperature independently influence germ cell differentiation and meiotic progression in <i>Trachemys scripta</i>

In species with genetic sex determination (GSD), the sex identity of the soma determines germ cell fate. For example, in mice, XY germ cells that enter an ovary differentiate as oogonia, whereas XX germ cells that enter a testis initiate differentiation as spermatogonia. However, numerous species lack a GSD system and instead display temperature-dependent sex determination (TSD). In the red-eared slider turtle, Trachemys scripta , a TSD model species with a warm female promoting temperature (FPT) and cool male promoting temperature (MPT) system, temperature directly affects germ cell number. In this study, we examined whether temperature directly affects other aspects of germ cell differentiation/sex identity. We uncoupled temperature and the sexual fate of the gonad by incubating eggs at MPT and treating with 17β-estradiol, a scheme that invariably produces ovaries. Through analysis of meiotic spreads, we showed that germ cells in FPT ovaries follow the typical pattern of initiating meiosis and progress through prophase I. However, in E2-induced ovaries that incubated at MPT, germ cells entered prophase I yet fail to exhibit synapsis. These results, combined with our single-cell transcriptome analysis, reveal a direct effect of temperature on germ cell sexual differentiation independent of its effect on the gonadal soma. These results imply that not all events of meiosis are under somatic control, at least not in this TSD species.

The changing relationship between racial identity and skin color in Brazil

In recent years, Brazil’s non-White (Brown and Black) population became a numerical majority for the first time since the 19th century. Although we know this change was mostly due to racial reclassification, we do not know how such changes are related to skin color, the primary marker of race in Brazil. Using data from six Latin American Public Opinion Project (LAPOP), or America’s Barometer, surveys from 2010 to 2023, we examine how changes in racial self-identification (White, Brown, or Black) are related to respondent skin color (light, medium, or dark). We ask how the association between self-identified race and skin color changed over the 13-y period and to what extent these trends varied by educational level. We found a “darkening” of racial identification over time, especially among those with medium and dark skin, who increasingly identified as Black. Brazilians with light skin increasingly identified as Brown, but this was partly explained by changes in interviewer reporting of skin color in the same period. We found only minor evidence that education level was related to changing racial classification over time. Our findings further understanding of recent trends in racial reclassification, which may reflect growing Black consciousness and the extension of racial quotas to both Brown and Black Brazilians in federal universities and public sector jobs.

Deletion of metal transporter Zip14 reduces major histocompatibility complex II expression in murine small intestinal epithelial cells

Documented worldwide, impaired immunity is a cardinal signature resulting from loss of dietary zinc, an essential micronutrient. A steady supply of zinc to meet cellular requirements is regulated by an array of zinc transporters. Deletion of the transporter Zip14 (Slc39a14) in mice produced intestinal inflammation. Elevated fecal lipocalin-2, calprotectin, IgG levels, and dysbiosis support the inflammatory phenotype. Here, we show through RNA-sequencing, using purified intestinal epithelial cells (IECs), that Zip14 deletion produces markedly reduced expression of major histocompatibility complex class II (MHCII) molecules and the master MHCII transactivator ( Ciita ). qPCR, western analysis, and immunohistochemistry confirmed loss of MHCII. Spectrofluorimetry with zinc probe FluoZin-3 showed reduced labile zinc in IECs from knockout mice. Chromatin immunoprecipitation assays, using Ciita antibody and IEC chromatin, suggest decreased transcription accounts for depressed expression of specific MHCII genes. Assay for Transposase-Accessible Chromatin (ATAC) sequencing (ATAC-seq) demonstrated that H2-Aa , H2-Ab1 and other MHCII genes result from chromatin remodeling yielding closed chromatin at regulatory regions of these genes. In agreement, ATAC-seq showed peak density of the chromosomal regulatory region of Ciita is consistent with down regulation of specific MHCII genes in IECs with Zip14 loss. Finally, dietary zinc supplementation of knockout mice and zinc supplementation of intestinal organoids with Zip14 deletion restored transcript levels. Taken together, our data suggest that cellular zinc delivery, via Zip14, is necessary for proper chromatin occupancy, required for normal MHCII expression and effective immune functions, and to preclude inflammatory disorders of the small intestine.

Reply to Zhang et al.: Parallel vector memories are required to explain all behavioral data in navigating bumblebees

Zoos must embrace animal death for education and conservation

Confined cell migration along extracellular matrix space in vivo

Collective migration of cancer cells is often interpreted using concepts derived from the physics of active matter, but the experimental evidence is mostly restricted to observations made in vitro. Here, we study collective invasion of metastatic cancer cells injected into the mouse deep dermis using intravital multiphoton microscopy combined with a skin window technique and three-dimensional quantitative image analysis. We observe a multicellular but low-cohesive migration mode characterized by rotational patterns which self-organize into antiparallel persistent tracks with orientational nematic order. We analyze the deformations induced by the cells in the extracellular matrix and find broadly distributed strain bands with a prevalence of compression. A model of active nematic hydrodynamics is able to describe several statistical features of the experimentally observed flow, suggesting that collective cancer cell invasion can be interpreted as a nematic active fluid in the turbulent regime. Our results help elucidate the migration patterns of cancer cells in vivo and provide quantitative guidance for the development of realistic in vitro and in silico models for collective cell migration.

Efficacy of GABA aminotransferase inactivator OV329 in models of neuropathic and inflammatory pain without tolerance or addiction

Dysregulation of GABAergic inhibition is associated with pathological pain. Consequently, enhancement of GABAergic transmission represents a potential analgesic strategy. However, therapeutic potential of current GABA agonists and modulators is limited by unwanted side effects. We postulated that inhibition of GABA’s degradation enzyme, GABA aminotransferase (GABA-AT), would increase endogenous GABA levels and produce analgesia. We evaluated antinociceptive efficacy of the potent GABA-AT inhibitor OV329 in rodent models of neuropathic and inflammatory pain and assessed possible side effects (i.e., reward and motor impairment). OV329 attenuated the development and maintenance of mechanical and cold hypersensitivities induced by the chemotherapeutic agent paclitaxel. Prophylactic OV329, administered systemically, normalized paclitaxel-induced increases in glutamate levels and suppressed neuropathic nociception. Intrathecal OV329 suppressed paclitaxel-induced mechanical hypersensitivity, elevating GABA, and reducing glutamate levels in the lumbar spinal cord, consistent with a spinal site of action. Furthermore, OV329 largely synergized with paclitaxel to enhance 4T1 tumor cell line cytotoxicity without altering viability of nontumor cells. OV329 also attenuated inflammation-induced mechanical hypersensitivity induced by intraplanar injection of complete Freund’s adjuvant (CFA) with efficacy comparable to morphine. Unlike morphine, OV329 did not produce reward in a conditioned place preference assay in mice and was not self-administered intravenously by rats. Antinociceptive efficacy of OV329 was observed at doses that did not impair motor function or produce tolerance following chronic dosing. Thus, inhibition of GABA-AT with OV329 represents a unique therapeutic strategy to alleviate neuropathic and inflammatory pain with no apparent abuse liability, potentially producing a beneficial spectrum of pharmacological effects through enzymatic regulation.

Retinal ganglion cells encode the direction of motion outside their classical receptive field

Retinal ganglion cells (RGCs) typically respond to light stimulation over their spatially restricted receptive field. Using large-scale recordings in the mouse retina, we show that a subset of non- direction-selective (DS) RGCs exhibit asymmetric activity, selective to motion direction, in response to a stimulus crossing an area far beyond the classic receptive field. The extraclassical response arises via inputs from an asymmetric distal zone and is enhanced by desensitization mechanisms and an inherent DS component, creating a network of neurons responding to motion toward the optic disc. Pharmacological manipulations revealed the necessity of glycinergic amacrine cells for this response. Using in vivo recordings, we identified similar extraclassical responses in lateral geniculate nucleus neurons, suggesting such non conventional DS information is transferred to downstream structures. Our results suggest a complex integration of motion direction processing across the visual field, which arises beyond the classical receptive field boundaries.

Chromatin enables precise and scalable gene regulation with factors of limited specificity

Biophysical constraints limit the specificity with which transcription factors (TFs) can target regulatory DNA. While individual nontarget binding events may be low affinity, the sheer number of such interactions could present a challenge for gene regulation by degrading its precision or possibly leading to an erroneous induction state. Chromatin can prevent nontarget binding by rendering DNA physically inaccessible to TFs, at the cost of energy-consuming remodeling orchestrated by pioneer factors (PFs). Under what conditions and by how much can chromatin reduce regulatory errors on a global scale? We use a theoretical approach to compare two scenarios for gene regulation: one that relies on TF binding to free DNA alone and one that uses a combination of TFs and chromatin-regulating PFs to achieve desired gene expression patterns. We find, first, that chromatin effectively silences groups of genes that should be simultaneously OFF, thereby allowing more accurate graded control of expression for the remaining ON genes. Second, chromatin buffers the deleterious consequences of nontarget binding as the number of OFF genes grows, permitting a substantial expansion in regulatory complexity. Third, chromatin-based regulation productively co-opts nontarget TF binding for ON genes in order to establish a “leaky” baseline expression level, which targeted activator or repressor binding subsequently up- or down-modulates. Thus, on a global scale, using chromatin simultaneously alleviates pressure for high specificity of regulatory interactions and enables an increase in genome size with minimal impact on global expression error.

Electrochemical NAD+ regeneration in bacterial organelles

The 1831 CE mystery eruption identified as Zavaritskii caldera, Simushir Island (Kurils)

Polar ice cores and historical records evidence a large-magnitude volcanic eruption in 1831 CE. This event was estimated to have injected ~13 Tg of sulfur (S) into the stratosphere which produced various atmospheric optical phenomena and led to Northern Hemisphere climate cooling of ~1 °C. The source of this volcanic event remains enigmatic, though one hypothesis has linked it to a modest phreatomagmatic eruption of Ferdinandea in the Strait of Sicily, which may have emitted additional S through magma–crust interactions with evaporite rocks. Here, we undertake a high-resolution multiproxy geochemical analysis of ice-core archives spanning the 1831 CE volcanic event. S isotopes confirm a major Northern Hemisphere stratospheric eruption but, importantly, rule out significant contributions from external evaporite S. In multiple ice cores, we identify cryptotephra layers of low K andesite-dacite glass shards occurring in summer 1831 CE and immediately prior to the stratospheric S fallout. This tephra matches the chemistry of the youngest Plinian eruption of Zavaritskii, a remote nested caldera on Simushir Island (Kurils). Radiocarbon ages confirm a recent (&lt;300 y) eruption of Zavaritskii, and erupted volume estimates are consistent with a magnitude 5 to 6 event. The reconstructed radiative forcing of Zavaritskii (−2 ± 1 W m −2 ) is comparable to the 1991 CE Pinatubo eruption and can readily account for the climate cooling in 1831–1833 CE. These data provide compelling evidence that Zavaritskii was the source of the 1831 CE mystery eruption and solve a confounding case of multiple closely spaced observed and unobserved volcanic eruptions.

A detailed spatiotemporal atlas of the white matter tracts for the fetal brain

This study presents the construction of a comprehensive spatiotemporal atlas of white matter tracts in the fetal brain for every gestational week between 23 and 36 wk using diffusion MRI (dMRI). Our research leverages data collected from fetal MRI scans, capturing the dynamic changes in the brain’s architecture and microstructure during this critical period. The atlas includes 60 distinct white matter tracts, including commissural, projection, and association fibers. We employed advanced fetal dMRI processing techniques and tractography to map and characterize the developmental trajectories of these tracts. Our findings reveal that the development of these tracts is characterized by complex patterns of fractional anisotropy (FA) and mean diffusivity (MD), coinciding with the intensity of histogenic processes such as axonal growth, involution of the radial-glial scaffolding, and synaptic pruning. This atlas can serve as a useful resource for neuroscience research and clinical practice, improving our understanding of the fetal brain and potentially aiding in the early diagnosis of neurodevelopmental disorders. By detailing the normal progression of white matter tract development, the atlas can be used as a benchmark for identifying deviations that may indicate neurological anomalies or predispositions to disorders.

Integrin-activating <i>Yersinia</i> protein Invasin sustains long-term expansion of primary epithelial cells as 2D organoid sheets

Matrigel ® /BME ® , a basement membrane-like preparation, supports long-term growth of epithelial 3D organoids from adult stem cells [T. Sato et al. , Nature 459 , 262–265 (2009); T. Sato et al. , Gastroenterology 141 , 1762–1772 (2011)]. Here, we show that interaction between Matrigel’s major component laminin-111 with epithelial α6β1-integrin is crucial for this process. The outer membrane protein Invasin of Yersinia is known to activate multiple integrin–β1 complexes, including integrin α6β1. A C-terminal integrin-binding fragment of Invasin, coated on culture plates, mediated gut epithelial cell adhesion. Addition of organoid growth factors allowed multipassage expansion in 2D. Polarization, junction formation, and generation of enterocytes, goblet cells, Paneth cells, and enteroendocrine cells were stable over time. Sustained expansion of other human, mouse, and even snake epithelia was accomplished under comparable conditions. The 2D “organoid sheet” format holds advantages over the 3D “in gel” format in terms of imaging, accessibility of basal and apical domains, and automation for high-throughput screening. Invasin represents a fully defined, affordable, versatile, and animal-free complement to Matrigel ® /BME ® .

Moisture-driven carbonation kinetics for ultrafast CO ₂ mineralization

CO 2 mineralization, a process where CO 2 reacts with minerals to form stable carbonates, presents a sustainable approach for CO 2 sequestration and mitigation of global warming. While the crucial role of water in regulating CO 2 mineralization efficiency is widely acknowledged, a comprehensive understanding of the underlying mechanisms remains elusive. This study employs a combined experimental and atomistic simulation approach to elucidate the intricate mechanisms governing moisture-driven carbonation kinetics of calcium-bearing minerals. A self-designed carbonation reactor equipped with an ultrasonic atomizer is used to meticulously control the water content during carbonation experiments. Grand Canonical Monte Carlo simulations reveal that maximum CO 2 uptake occurs at a critical water content where the initiation of capillary condensation significantly enhanced liquid–gas interactions. This phenomenon leads to CO 2 adsorption–driven ultrafast carbonation at an optimal moisture content (0.1 to 0.2 g/g, water mass ratio to total wet mass of the mineral). A higher moisture content decimates the carbonation rate by crippling CO 2 intake within mineral pores. However, at exceptionally high moisture levels, the carbonation reaction sites shift from internal mesopores to the grain surface. This results in surface dissolution–driven ultrafast carbonation, attributed to the monotonically decreasing free energy of dissolution with increasing surface water thickness, as revealed by metadynamics simulations. This study provides a fundamental and unified understanding of the multifaceted role of water in mineral carbonation, paving the way for optimizing ultrafast CO 2 mineralization strategies for global decarbonization efforts.

RNAi of the elastomeric protein resilin reduces jump velocity and resilience to damage in locusts

Resilin, an elastomeric protein with remarkable physical properties that outperforms synthetic rubbers, is a near-ubiquitous feature of the power amplification mechanisms used by jumping insects. Catapult-like mechanisms, which incorporate elastic energy stores formed from a composite of stiff cuticle and resilin, are frequently used by insects to translate slow muscle contractions into rapid-release recoil movements. The precise role of resilin in these jumping mechanisms remains unclear, however. We used RNAi to reduce resilin deposition in the principal energy-storing springs of the desert locust ( Schistocerca gregaria ) before measuring jumping performance. Knockdown reduced the amount of resilin-associated fluorescence in the semilunar processes (SLPs) by 44% and reduced the cross-sectional area of the tendons of the hind leg extensor-tibiae muscle by 31%. This affected jumping in three ways: First, take-off velocity was reduced by 15% in knockdown animals, which could be explained by a change in the extrinsic stiffness of the extensor-tibiae tendon caused by the decrease in its cross-sectional area. Second, knockdown resulted in permanent breakages in the hind legs of 29% of knockdown locusts as tested by electrical stimulation of the extensor muscle, but none in controls. Third, knockdown locusts exhibited a greater decline in distance jumped when made to jump in rapid succession than did controls. We conclude that stiff cuticle acts as the principal elastic energy store for insect jumping, while resilin protects these more brittle structures against breakage from repeated use.

Earliest evidence of sedentism in the Antilles: Multiple isotope data from Canímar Abajo, Cuba

The early populations that inhabited the Antilles were traditionally understood as highly mobile groups of hunters/fishers and gatherers. Although more recent data have demonstrated that some populations engaged in the production of domestic plants and cultivars, questions remain about other aspects of their lifeways, including whether the adoption of domesticates was accompanied by a decrease in residential mobility. The level of sedentism in a population is an instrumental variable to understand community social relations and complexity, adaptations, and lifeways. Here, we combined enamel strontium ( 87 Sr/ 86 Sr), oxygen (δ 18 O en ), and carbon (δ 13 C en ) isotopes of 44 human teeth from the site of Canímar Abajo—where the oldest human remains from the insular Caribbean have been reported—to examine the mobility patterns of early Antillean groups. In contrast with traditional narratives, the homogeneous strontium isotope values observed in most individuals from the older funerary area of the site (cal. BC 2237–790) were consistent with the pattern expected for a sedentary population subsisting primarily on local resources obtained close to the coast. The isotopic evidence reveals that between cal. AD 403–1282, the mound was reused for funerary practices by both local communities and nonlocal individuals. The evidence suggests that this period saw higher population mobility, with influxes of individuals from more distant locations and diverse dietary and burial traditions. The isotope results from Canímar Abajo provide the earliest isotopic evidence of populations with low-level residential mobility in the Antilles.

Family relations of Moche elite burials on the North Coast of Peru (~500 CE): Analyses of the Señora de Cao and relatives

The Moche archaeological culture flourished along Peru’s North Coast between the 4th and 10th centuries CE and was characterized by a complex social hierarchy dominated by political and religious elites. Previous archaeological evidence suggests kinship was a key factor in maintaining political authority within Moche society. To test this hypothesis, we applied archaeological, genetic, and isotopic methods to examine familial relationships between six individuals, including the prominent Señora de Cao ( ~500 CE ), buried together in a pyramid-like, painted temple, Huaca Cao Viejo, in the Chicama Valley, Peru. Our findings reveal that all six individuals were biologically related, with varying degrees of kinship. The Señora de Cao was interred with a sacrificed juvenile, identified as a possible niece, and at least one, and potentially two siblings and a grandparent in separate tombs nearby. One of the male siblings was accompanied in death by his sacrificed son. Isotopic analysis indicates that while most individuals had diets rich in maize and animal protein and spent their childhoods in or near the Chicama Valley, the sacrificed juvenile accompanying the Señora had a distinct diet and geographic origin. These results demonstrate that Moche elites were interred with family members, including some raised far from their parental homes. This supports the hypothesis that kinship was central to transmitting status and authority. Moreover, sacrificing family members to accompany deceased elites underscores the significance of ritual sacrifice in reinforcing familial ties and linking the deceased to both ancestors and the divine.

Comparing cooperative geometric puzzle solving in ants versus humans

Biological ensembles use collective intelligence to tackle challenges together, but suboptimal coordination can undermine the effectiveness of group cognition. Testing whether collective cognition exceeds that of the individual is often impractical since different organizational scales tend to face disjoint problems. One exception is the problem of navigating large loads through complex environments and toward a given target. People and ants stand out in their ability to efficiently perform this task not just individually but also as a group. This provides a rare opportunity to empirically compare problem-solving skills and cognitive traits across species and group sizes. Here, we challenge people and ants with the same “piano-movers” load maneuvering puzzle and show that while ants perform more efficiently in larger groups, the opposite is true for humans. We find that although individual ants cannot grasp the global nature of the puzzle, their collective motion translates into emergent cognitive skills. They encode short-term memory in their internally ordered state and this allows for enhanced group performance. People comprehend the puzzle in a way that allows them to explore a reduced search space and, on average, outperform ants. However, when communication is restricted, groups of people resort to the most obvious maneuvers to facilitate consensus. This is reminiscent of ant behavior, and negatively impacts their performance. Our results exemplify how simple minds can easily enjoy scalability while complex brains require extensive communication to cooperate efficiently.