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The Visceral Adiposity Index (VAI) assesses visceral fat and related metabolic risks. However, its precise correlation with sarcopenia is unclear. This study aimed to examine this correlation. A cross-sectional analysis was conducted using NHANES data from 2011 to 2018. To correct VAI skewness, a logarithmic transformation was applied. Multiple covariates were included, and logistic regression was employed to explore the relationship between VAI and sarcopenia. Restricted cubic spline (RCS) and threshold saturation analyses were used to investigate the nonlinear relationship. Subgroup analyses evaluated the effects of various stratification factors. Sensitivity and additive analyses tested the robustness of the findings. The study included 4688 individuals. Participants with sarcopenia had significantly higher VAI values. Logistic regression revealed a significant positive connection between Log VAI and sarcopenia (OR 2.09, 95% CI 1.80–2.43) after adjusting for variables. RCS analysis showed a nonlinear correlation, identifying a breakpoint at VAI = 1.51. To the left of this breakpoint, each unit increase in VAI significantly correlated with a higher likelihood of sarcopenia (OR 2.54, 95% CI 1.74–3.79); to the right, increases in VAI did not significantly affect prevalence. Subgroup analyses suggested VAI as an independent risk factor. Sensitivity and additive analyses confirmed the main findings' robustness. Among American adults, the VAI is significantly associated with sarcopenia, with higher VAI values potentially increasing the prevalence of sarcopenia. Monitoring VAI is critical for early identification of high-risk individuals and interventions to delay or minimize the onset and progression of sarcopenia. [ABSTRACT FROM AUTHOR]

[Objective] This study examined the ecological and hydrological variability and regime shift during the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) in the middle reaches of the Yangtze River. This region is climatically governed by the Asian monsoon, with increased precipitation in summer and decreased in winter. Our study helps deepen our understanding of the history of the regional ecological and hydrological changes and their connections to the monsoon climate. [Methods] Based on two high-resolution stalagmite (YX262 and YX275) δ13C records from Yongxing cave, Hubei province in the middle reaches of the Yangtze River, we reconstructed the history of the local paleoclimate and environment from 1 044-1 954 A.D. by creating a composite of the two records using the iscam program. [Results] The δ13C records show two completely different states during the MCA and LIA, with the lower δ13C values characterizing the MCA period, and the higher δ13 C values the LIA. During the transition from MCA to LIA, δ13C shows an abrupt change. This phenomenon indicates a regime shift from a strong to weak state for the vegetation respiration activity and precipitation variation. This variation is consistent with many stalagmite δ13C records in southwest China and the middle reaches of the Yangtze River. Here, our stalagmite δ13C record shows that the shift of the vegetation cover was rapid from the MCA to LIA. A Rampfit analysis shows that the stalagmite δ13C shift occurred between 1 434-1 460 A.D., lasting 26 years, which is more rapid and significantly longer than the stalagmite δ18O shift. This variation is attributed to both climate deterioration and human activity influences, leading to a reduction of vegetation cover during this period. On the one hand, the rapid transformation of the stalagmite δ13C record in Yongxing cave may be related to the great migration event in the early Ming Dynasty. A large number of migrants swarmed into Hubei province, inevitably leading to large-scale deforestation and land reclamation and changing the ecological environment of the surface soil vegetation. Those behaviors cause positive stalagmite δ13C. On the other hand, the Yongxing δ13C record is correlated with changes in the total solar radiation, intertropical convergence zone (ITCZ), temperature in eastern China, and El Nino-Southern Oscillation (ENSO) on the MCA and LIA event scales. During the MCA period, the total solar irradiance was larger, and the ITCZ was farther north, with a high frequency of El Nino states. However, during the LIA period, the total solar irradiance was relatively small, and the position of ITCZ was more southerly, in the low frequency period of El Nino states. This correlation indicates that the changes of hydrological circulation and vegetation cover in the middle reaches of the Yangtze River had a dynamic relationship with the regional and global climate change during the past millennium, and the impacts of human activities on surface vegetation may be related to the background of regional or global climate change. [Conclusions] By studying the δ13 C record of stalagmites in Yongxing cave in the past millennium, the eco-hydrological characteristics of MCA and LIA were found to be significantly different, which may be related to global climate change and human activities. The study not only clearly establishes the time boundary between MCA and LIA in the middle reaches of the Yangtze River, but also deepens our understanding of the characteristics and causes of eco-hydrological environment changes in the region during the two periods. [ABSTRACT FROM AUTHOR]

In the Basilicata region, located in southern Italy and known for hosting among the first occurrences of the Acheulean culture in southwestern Europe, the Lower Paleolithic site of Loreto at Venosa is located less than a kilometer from the emblematic site of Notarchirico and less than 25 km from Cimitero di Atella. The Loreto site has not been studied as thoroughly as the two other sites and, although geological investigations have been carried out in the Venosa basin, no direct numerical dating has ever been published for the three archaeological levels brought to light during the excavation campaigns. We present a multi-method geochronological approach combining ESR/U-series, ESR, and 40Ar/39Ar permitting to refine the age of the most ancient archaeological level (A) of the Loreto site. These data allow us to propose an MIS 13 age for this level, in accordance with previous hypotheses based on geological and paleontological data. We also propose a technical review of the lithic tools preserved in the collection of the National Archaeological Museum of Venosa to integrate Loreto in the evolution scheme of the European Acheulean techno-complex emergence and diffusion. [ABSTRACT FROM AUTHOR]

The giant panda, currently restricted to a small region of central China, was once widely dispersed throughout southern China and even some parts of continental Southeast Asia during the Pleistocene epoch. However, the evolutionary process and intraspecific variation remain poorly understood in light of limited fossil records, which are usually isolated teeth and a few fragmentary skulls and mandibles. Here we report three skulls, two of which are nearly complete, of Ailuropoda melanoleuca baconi from Yanjinggou in China, which represent the best-preserved skull material ever recorded for this paleosubspecies. A. m. baconi, characterized by a large and robust body, extremely developed zygomatic arches, a moderately developed sagittal crest, and a medium-rough external surface of the supraoccipital, exoccipital, and ascending ramus compared with Ailuropoda microta and other paleosubspecies and living subspecies of A. melanoleuca, can be regarded as a valid paleosubspecies. Ailuropoda fovealis or Ailuropoda melanoleuca fovealis turns out to be a synonym of A. m. baconi. The intraspecific variation of A. m. baconi is far more complicated than generally accepted. Based on comparisons with A. microta, A. m. wulingshanensis, and modern Ailuropoda melanoleuca, we propose that the evolutionary tendency of the skull appears to be much clearer than that of the teeth and that the increase in body size and the enhancement of the masticatory system can be deemed as the main evolutionary changes in this part of the Ailuropoda lineage. Meanwhile, our study for the first time provides a numerical age (ca. 0.35–0.26 Ma) for the Yanjinggou fauna, which is generally considered as a mixture of the middle Early Pleistocene fauna and the Mid-Late Pleistocene fauna. [ABSTRACT FROM AUTHOR]

The rainfall changes in East Asian summer monsoon (EASM) regions on the orbital timescale remain controversial due to the lack of reliable rainfall records. Here, we present new multiproxy records (δ18O, δ13C, Sr/Ca and Mg/Ca) of a 230Th-dated stalagmite from Hulu Cave in central eastern China. Multiproxy records reconstruct a regional hydroclimate history from 340 to 261 kyr BP (thousand years before present), approximately covering the antepenultimate glacial period. The δ18O record is dominated by the precessional cycles, suggesting that EASM responds to changes in Northern Hemisphere summer insolation (NHSI) on the orbital timescale. Significant correlations amongst the δ13C, Sr/Ca and Mg/Ca suggest that a common factor, i.e., the local hydrological cycle, controlled their variability, and their leading principal component can be used as a proxy linked to regional rainfall. This composite record bears a good similarity to those from the Chinese Loess Plateau, showing a gradually decreasing rainfall during the antepenultimate glacial period, consistent with changes in global ice volume. Superimposed on the long-term trend, three relative wetter intervals were responding to the higher NHSI periods, suggesting that EASM rainfall variability was induced by integrated effects of global ice volume and NHSI. The increased ice sheets and lower NHSI resulted in an increased meridional temperature gradient and southward shift of the westerlies, which shortened the duration of Meiyu and midsummer rainfall. The differences between the rainfall record and the stalagmite δ18O record indicate that the latter represents the overall EASM intensity linked to monsoon circulation, but does not directly reflect the rainfall changes at the cave sites. [ABSTRACT FROM AUTHOR]

The age when the giant panda (Ailuropoda melanoleuca) transitioned to a bamboo dominant diet has not been well established due to the lack of fossil evidence. In particular, a radial sesamoid bone, which acts as a 'pseudo-thumb', has been used as evidence of giant pandas' adaptive evolution to bamboo specialised consumption, but no relevant fossil evidence has been reported thus far. Shuanghe Cave is the longest cave in Asia, and produced fossils of more than 20 giant pandas, including relatively intact fossil skeletons of two adult giant pandas. The uranium-series dating of the fossilised teeth of the two giant pandas indicates ages earlier than 102 ka and 49 ka. Tooth wear for both individuals is not apparent, indicating that they were young at the time of death. From the skeletal fossils, for the first time, a 'pseudo-thumb' fossil of a giant panda was discovered. Our morphological comparison indicated that as early as 100,000 years ago, giant pandas had evolved an enlarged radial sesamoid bone (pseudo-thumb) that is comparable to that of the modern pandas, suggesting that in the early Late Pleistocene at the latest, giant pandas possessed physical conditions allowing them to dexterously grab bamboo with their manuss. [ABSTRACT FROM AUTHOR]

North African coastal Middle Stone Age (MSA) sites are key to study the development and expansion of early H. sapiens. El Mnasra cave on the Atlantic coast of Morocco (Témara region) is a crucial site associated with MSA archaeological materials considered advanced cognitive hallmarks of behavioural innovation, such as numerous Nassariidae perforated shells, hematite pigments, bones industry and coastal resources exploitation. We provide new trapped-charges dates (OSL and combined US-ESR ages). Our Bayesian modelling strengthens the new lithostratigraphic interpretation of the cave stratigraphic units (US) and we propose an updated chronostratigraphic model for the Middle Stone Age archaeo-sequence of El Mnasra Cave. We confirm a human presence between 124–104 ka, earlier than what the previous OSL and US-ESR data showed. Our time range intervals allowed us to also extend the age of the MSA occupations considerably to the MIS 4/3 (~62–30 ka), marked by the disappearance of the Nassariidae perforated shells. Outstandingly, our model pushed back the age of the largest record of Nassariidae perforated shells and placed the age of their use by the Aterian groups at El Mnasra from the MIS 5d-5b (~115–94 ka). [ABSTRACT FROM AUTHOR]

The isotopic records of two 230Th-dated stalagmites from Longfugong Cave, Mt. Shennongjia, central China, reveal a highly resolved Asian summer monsoon (ASM) history from 29.5 to 14.5 ka BP. The two δ18O records are consistent with other Chinese cave δ18O records, suggesting that our new records are of regional significance. Due to the reservoir mixing of seepage water in the epikarst system, the stalagmite δ18O signals in this cave are more severely muted than those in other caves. Here, we observed that the amplitude of the δ13C variability is approximately twice that of the δ18O signal and can be used as a sensitive proxy of East Asian monsoon climates. First, the two stalagmite δ13C records are consistent with each other on decadal to centennial timescales. Second, there are high correlation coefficients between the δ13C and δ18O signals over shorter timescales. Third, from 25.2 to 19.6 ka BP, six peaks in the δ13C records were identified and are coincident with corresponding warming events in the Greenland ice-core δ18O records, suggesting that strong coupling occurred between the high- and low-latitude northern climates on centennial timescales. Therefore, we propose that atmospheric transmission mechanisms probably played an important role in linking the ASM and Greenland climates on short timescales. A shift in westerly winds associated with variability in the extent of temperature in the North Atlantic likely influenced changes in hydrological and thermal conditions at the cave site, leading to changes in vegetation cover and soil CO2 concentrations above the cave. Therefore, the calcite δ13C records probably had faster and more sensitive responses to rapid climate shifts compared with their related δ18O records. [ABSTRACT FROM AUTHOR]

To date, in Africa, evidence for animal processing and consumption in caves routinely used as living spaces is only documented in the late Middle Pleistocene of the North and South of the continent and postdates the Middle Pleistocene in East Africa. Here we report the earliest evidence in a North-African cave (Grotte des Rhinocéros at Casablanca, Morocco) of cut, percussion and human gnawing marks on faunal remains directly associated with lithic knapping activities in the same space and in a well-documented stratified context. Ages for this Acheulean site are provided by the dating of herbivorous teeth to 690–720 ka and 520–550 ka (lower and upper sets) by combined Electron Spin Resonance (ESR) and U-series techniques. Traces of butchery on gazelle, alcelaphin, and zebra bones demonstrate that hominins had primary access to herbivore carcasses. Hominins brought and consumed meat in the cave, as documented by herbivore bones bearing human tooth marks concentrated in a circumscribed area of the excavation. In Africa, this site provides the earliest evidence for in situ carcass processing and meat-eating in cave, directly associated with lithic production and demonstrates the recurrent use by early Middle Pleistocene hominins of a North African cave site 400 000 years before that by Homo sapiens at Jebel Irhoud (Morocco). [ABSTRACT FROM AUTHOR]

Variations of precipitation, also called the Meiyu rain, in the East Asian summer monsoon (EASM) domain during the last millennium could help enlighten the hydrological response to future global warming. Here we present a precisely dated and highly resolved stalagmite δ18O record from the Yongxing Cave, central China. Our new record, combined with a previously published one from the same cave, indicates that the Meiyu rain has changed dramatically in association with the global temperature change. In particular, our record shows that the Meiyu rain was weakened during the Medieval Climate Anomaly (MCA) but intensified during the Little Ice Age (LIA). During the Current Warm Period (CWP), our record indicates a similar weakening of the Meiyu rain. Furthermore, during the MCA and CWP, our records show that the atmospheric precipitation is similarly wet in northern China and similarly dry in central China, but relatively wet during the CWP in southern China. This spatial discrepancy indicates a complicated localized response of the regional precipitation to the anthropogenic forcing. The weakened (intensified) Meiyu rain during the MCA (LIA) matches well with the warm (cold) phases of Northern Hemisphere surface air temperature. This Meiyu rain pattern also corresponds well to the climatic conditions over the tropical Indo-Pacific warm pool. On the other hand, our record shows a strong association with the North Atlantic climate as well. The reduced (increased) Meiyu rain correlates well with positive (negative) phases of the North Atlantic Oscillation. In addition, our record links well to the strong (weak) Atlantic meridional overturning circulation during the MCA (LIA) period. All abovementioned localized correspondences and remote teleconnections on decadal to centennial timescales indicate that the Meiyu rain was coupled closely with oceanic processes in the tropical Pacific and North Atlantic oceans during the MCA and LIA. [ABSTRACT FROM AUTHOR]

A 230Th/U-dated stalagmite from Hulu Cave was analyzed for δ18O, δ13C, and trace elements. A ~10-yr-resolution δ18O record, spanning 51.7–42.6 ka, revealed Dansgaard-Oeschger (DO) events 14 to 11. A similar rapid transition and synchronous timing of the onset of DO 12 is evident between the Greenland and Hulu Cave records, which suggests a common forcing mechanism of DO cycles in the North Atlantic and monsoonal region of Asia. Centennial-scale monsoonal oscillations in the cave δ18O record are indicative of hydroclimatic instability during interstadials. After removing the signals of remote moisture sources, the proportion of moisture from nearby sources is found to be higher during stadials than during interstadials. To explain this, we propose that the movement of the westerly jet is an important control on the balance of nearby and distant moisture sources in East Asia. In addition, the records of δ13C and trace element ratios, which are proxies of local environmental changes, resemble the δ18O record on the scale of DO cycles, as well as on even shorter timescales. This suggests that hydrological processes and biological activity at the cave site respond sensitively to the monsoonal changes. [ABSTRACT FROM AUTHOR]

A precisely 230Th-dated stalagmite δ13C profile from Hulu Cave, China, is presented to characterize the frequency and pattern of millennial-scale Asian monsoon (AM) variability from 160.6 to 132.5 ka. Evidence for an antiphased relationship of the δ13C and δ18O on the millennial scale suggests that the δ13C is indicative of the local hydrological cycle associated with changes in AM strength. Owing to the δ13C responding to AM changes more sensitively than the δ18O, we could identify 15 strong AM events that correlate to cold intervals recorded in Antarctic ice cores within 230Th dating uncertainty. This result supports a dynamic link of AM strength and southern hemispheric climates via the cross-equatorial airflows. Power spectrum analysis shows a predominant periodicity of 1.5–2.5 ka for the δ13C profile, similar to the Dansgaard-Oeschger frequency during the last glacial period. Moreover, the AM events are characterized by rapid transitions at the onset, suggesting that the observed millennial-scale AM variability is likely forced by northern high-latitude climates via north–south shifts of the Intertropical Convergence Zone associated with the bipolar seesaw mechanism. As evidence for a common mechanism for ice age terminations, a strong AM event (~134 ka) surrounding Termination II is analogous to the Bølling-Allerød warming interval. [ABSTRACT FROM AUTHOR]

We present two isotopic (δ 18 O and δ 13 C) sequences of a twin-stalagmite from Zhuliuping Cave, southwestern China, with 230 Th dates from 14.6 to 4.6 ka. The stalagmite δ 18 O record characterizes orbital- to decadal-scale variability of Asian summer monsoon (ASM) intensity, with the Holocene optimum period (HOP) between 9.8 and 6.8 ka BP which is reinforced by its co-varying δ 13 C data. The large multi-decadal scale amplitude of the cave δ 18 O indicates its high sensitivity to climate change. Four centennial-scale weak ASM events during the early Holocene are centered at 11.2, 10.8, 9.1 and 8.2 ka. They can be correlated to cold periods in the northern high latitudes, possibly resulting from rapid dynamics of atmospheric circulation associated with North Atlantic cooling. The 8.2 ka event has an amplitude more than two-thirds that of the Younger Dryas (YD), and is significantly stronger than other cave records in the Asia monsoon region, likely indicating a more severe dry climate condition at the cave site. At the end of the YD event, the δ 13 C record lags the δ 18 O record by 300–500 yr, suggesting a multi-centennial slow response of vegetation and soil processes to monsoon enhancement. [ABSTRACT FROM AUTHOR]

Abstract: The combined U-series/electron spin resonance (ESR) dating method was applied to nine teeth from two Early Pleistocene archaeological sites located in the Orce area (Guadix-Baza Basin, Southern Spain): Fuente Nueva-3 (FN-3) and Barranco León (BL). The combination of biostratigraphy and magnetostratigraphy places both sites between the Olduvai and Jaramillo subchrons (1.78–1.07Ma). Our results highlight the difficulty of dating such old sites and point out the limits of the combined U-series/ESR dating method based on the US model. We identified several sources of uncertainties that may lead to inaccurate age estimates. Seven samples could not be dated because the dental tissues had (230Th/234U) activity ratios higher than equilibrium, indicating that uranium had probably leached from these tissues. It was however possible to calculate numerical estimates for two of the teeth, both from FN-3. One yielded a Middle Pleistocene age that seems to be strongly underestimated; the other provided an age of 1.19±0.21Ma, in agreement with data obtained from independent methods. The latter result gives encouragement that there are samples that can be used for routine dating of old sites. [Copyright &y& Elsevier]

The Mauer mandible, holotype of Homo heidelbergensis, was found in 1907 in fluvial sands deposited by the Neckar River 10 km southeast of Heidelberg, Germany. The fossil is an important key to understanding early human occupation of Europe north of the Alps. Given the associated mammal fauna and the geological context, the find layer has been placed in the early Middle Pleistocene, but confirmatory chronometric evidence has hitherto been missing. Here we show that two independent techniques, the combined electron spin resonance/U-series method used with mammal teeth and infrared radiofluorescence applied to sand grains, date the type-site of Homo heidelbergensis at Mauer to 60±40 ka. This result demonstrates that the mandible is the oldest hominin fossil reported to date from central and northern Europe and raises questions concerning the phyletic relationship of Homo heidelbergensis to more ancient populations documented from southern Europe and in Africa. We address the paleoanthropological significance of the Mauer jaw in light of this dating evidence. [ABSTRACT FROM AUTHOR]

The spotted hyena (Crocuta crocuta) is the only extant species of the genus Crocuta, which once occupied a much wider range during the Pliocene and Pleistocene. However, its origin and evolutionary history is somewhat contentious due to discordances between morphological, nuclear, and mitochondrial data. Due to the limited molecular data from east Asian Crocuta, also known as cave hyena, and the difficulty of extracting ancient DNA from this area, here we present proteomic analysis of cave hyenas from three locations in northern China. This marks the first proteomic data generated from cave hyenas, adding new molecular data to the east Asian populations. Phylogenetic analysis based on these protein sequences reveals two different groups of cave hyenas in east Asia, one of which could not be distinguished from modern spotted hyenas from northern Africa, tentatively the result of previously suggested gene flow between these lineages. With developments of instrumentation and analytical methods, proteomics holds promising potential for molecular phylogenetic reconstructions of ancient fauna previously thought to be unreachable using ancient DNA. [ABSTRACT FROM AUTHOR]

The study of geomagnetic excursions is key for understanding the behavior of the magnetic field of the Earth. In this paper, we present the geomagnetic record in a 2.29-m-long continuous core sampled in a flowstone in Liguria (Italy) and dated to the Lower Brunhes. The cored flowstone developed from Marine Isotopic Stage (MIS) 13 to MIS 7, according to 21 U-series dates. The mean growth rate is closely related to glacial and interglacial isotopic stages. Magnetic remanence was measured using u-channel and deconvolved. Four geomagnetic excursions were recorded at the same location, in a single flowstone, during interglacial MIS 11 and 13; Basura 1, 2, 3 and 4, at depths of 213 cm, 181, 160 and 92 cm, respectively. Due to the uncertainties of U-Th dating, the timing of the three events, namely Basura 1, 2 and 3 overlaps. The Basura 4 is well-dated to 417 + −7/8 ka and is clearly distinguishable from the others. It should therefore be considered as a possible excursion. [ABSTRACT FROM AUTHOR]