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Objectives: Inflammatory mediators are associated with many chronic diseases; however, their role in metabolic syndrome (Met-S) is not well documented. We therefore aimed to compare the serum markers of inflammation including C-reactive protein (CRP), myeloperoxidase (MPO), interleukin-6 (IL-6), tumour necrosis factor alpha (TNF- α ), and TNF- β in young military recruits with and without Met-S. We hypothesized that any significant change in inflammatory markers between the two groups would indicate the role of inflammation in Met-S that would help in future directions for screening and treatment of Met-S. Design and Methods . A total of 2010 adult men, aged 18-30 years, were divided into two groups: with Met-S ( N = 488) and without Met-S ( N = 1522), according to the International Diabetes Federation definition. We compared the serum levels of inflammatory biomarkers between the two groups. We also studied the correlations between the inflammatory markers and the components of Met-S to explore the biomarker potential of inflammatory markers for screening of Met-S. Logistic regression analysis was performed to test the association between inflammatory markers and Met-S., Results: A large number of subjects in the Met-S group were suffering from obesity. Out of the 2010 total subjects, only 731 (36.4%) had normal fasting blood sugar (FBS), while the prevalence of prediabetes and diabetes was significantly higher in subjects with Met-S. We observed significant increases in serum levels of CRP, MPO, IL-6, and TNF- β but not TNF- α in subjects with Met-S as compared to subjects without Met-S. All the markers of inflammation showed significant correlations with Met-S, triglycerides (TG), blood pressure, body mass index (BMI), and age; however, none of these markers were correlated with HDL. Logistic regression analysis showed a significant association between Met-S and inflammatory markers., Conclusions: Serum levels of CRP, MPO, IL-6, and TNF- β are significantly increased in young adults with Met-S. This is probably the first study reporting TNF- β levels in Met-S. Since a proinflammatory cascade precedes many years before the onset of cardiovascular disease, these inflammatory biomarkers could help in the monitoring of high-risk individuals with Met-S who will be requiring therapeutic intervention., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Abdulrahman K. Al Asmari et al.)

The U-series dating of young and 'dirty' speleothems is challenging due to difficulties in assessing the isotopic composition of detrital contaminants and the low-abundance of 230 Th generated in situ. Here we propose a new dating approach based on the comparison of a speleothem's paleomagnetic directions to reference curves from global paleomagnetic reconstructions. This approach is demonstrated on a stalagmite collected from the Soprador do Carvalho cave in the Central Region of Portugal. A radioisotopic age model, built using four U-series ages and three 14 C, suggests relatively steady carbonate precipitation from ~ 5760 BCE until ~ 1920 CE. Forty-five 6 mm-thick subsamples were analyzed using alternating field and thermal demagnetization protocols, providing well-defined, primary magnetic directions. An age model of the stalagmite was obtained by fitting its paleomagnetic record with the reference paleosecular variation curves obtained by previous paleo-reconstruction models, applying statistical bootstrapping analysis to define their best fit. The resulting age models fit closely with the radioisotopic age model but provide a significantly higher time resolution. We reach the same conclusion when applying this approach to another stalagmite from the Algarve region of Portugal. Our approach thus appears a promising alternative to date young speleothems with high detrital contents., (© 2022. The Author(s).)

The risk factors associated with metabolic syndrome (Met-S) including hypertension, hyperglycemia, central obesity, and dyslipidemia are preventable, particularly at their early stage. There are limited data available on the association between Met-S and preventable risk factors in young adults. We randomly selected 2,010 Saudis aged 18-30 years, who applied to be recruited in military colleges. All the procedures followed the guidelines of International Diabetes Federation. The results showed that out of 2,010 subjects, 4088 were affected with Met-S. The commonest risk factors were high blood sugar (63.6%), high systolic and diastolic blood pressures (63.3 and 37.3%), and high body mass index (57.5%). The prevalence of prediabetes and diabetes were 55.2 and 8.4%, respectively. Obesity, diabetes, hypertension, and hypertriglyceridemia were significantly associated with Met-S. The frequency of smoking was significantly linked with the development of Met-S. The prevalence of Met-S was found to be significantly higher in individuals with sedentary lifestyle. In conclusion, the results of this study clearly indicate that military recruits, who represent healthy young adults, are also prone to Met-S. The findings of this study will help in designing preventive measures as well as public awareness programs for controlling the high prevalence of Met-S in young adults., Competing Interests: Conflict of interest: The authors declare that there are no conflicts of interest in this work., (© 2022 Hamoud A. Al Shehri et al., published by De Gruyter.)

Carbonate cave deposits (speleothems) have been used widely for paleoclimate reconstructions; however, few studies have examined the utility of other speleothem-forming minerals for this purpose. Here we demonstrate for the first time that stable isotopes (δ 17 O, δ 18 O and δD) of structurally-bound gypsum (CaSO 4 ·2H 2 O) hydration water (GHW) can be used to infer paleoclimate. Specifically, we used a 63 cm-long gypsum stalactite from Sima Blanca Cave to reconstruct the climate history of SE Spain from ~ 800 BCE to ~ 800 CE. The gypsum stalactite indicates wet conditions in the cave and humid climate from ~ 200 BCE to 100 CE, at the time of the Roman Empire apogee in Hispania. From ~ 100 CE to ~ 600 CE, evaporation in the cave increased in response to regional aridification that peaked at ~ 500-600 CE, roughly coinciding with the transition between the Iberian Roman Humid Period and the Migration Period. Our record agrees with most Mediterranean and Iberian paleoclimate archives, demonstrating that stable isotopes of GHW in subaerial gypsum speleothems are a useful tool for paleoclimate reconstructions.

Geißenklösterle Cave (Germany) is one of the most important Paleolithic sites in Europe, as it is characterized by human occupation during the Middle and early Upper Paleolithic. Aurignacian layers prior to 37-38 ka cal BP feature both musical and figurative art objects that are linked to the early arrival in Europe of Homo sapiens. Middle Paleolithic layers yielded lithic artifacts attributed to Homo neanderthalensis. Since human occupation at the site is attributed to both Neanderthals and modern humans, chronology is essential to clarify the issues of Neanderthal disappearance, modern human expansion in Europe, and the origin of the Aurignacian in Western Europe. Electron spin resonance (ESR) dating was performed on fossil tooth enamel collected from the Middle Paleolithic layers, which are beyond the radiocarbon dating range, and from the nearly sterile 'transitional' geological horizon (GH) 17 and the lower Aurignacian deposits, to cross-check ESR ages with previous radiocarbon, thermoluminescence and ESR age results. The Middle Paleolithic layers were dated between 94 ± 10 ka (GH 21) and 55 ± 6 ka (GH 18) by ESR on tooth enamel. Mean ages for GH 17, at 46 ± 3 ka, and for the lower Aurignacian layers, at 37 ± 3 ka, are in agreement with previous dating results, thus supporting the reliability of ESR chronology for the base of the sequence where dating comparisons are not possible. These results suggest that Neanderthals occupied the site from Marine Isotope Stage (MIS) 5 to the second half of MIS 3 and confirm the antiquity of early Aurignacian deposits. The presence of an almost sterile layer that separates Middle and Upper Paleolithic occupations could be related to the abandonment of the site by Neanderthals, possibly during Heinrich Stadial 5 (ca. 49-47 ka), thus before the arrival of H. sapiens in the area around 42 ka cal BP. These dates for the Middle Paleolithic of the Swabian Jura represent an important contribution to the prehistory of the region, where nearly all of the excavations were conducted decades ago and prior to the development of reliable radiometric dating beyond the range of radiocarbon., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

U-series disequilibrium measurements carried out on thermogenic travertine samples from a 12.6 m-long core and a 10 m-thick section from southeastern Morocco yielded finite ages ranging from 500 ka to the present-day, as well as two clusters determined to be older than 500 ka. The calculation of initial 234 U/ 238 U activity ratios in all samples younger than 500 ka shows high, reasonably constant values, with an average of 5.172 ± 0.520 (one standard deviation). Assuming that this value prevailed for periods older than 500 ka, we derived ages of up to approximately 1.2 Ma using the initial 234 U excess decay. Our results indicate that the two older clusters have ages of 776 ± 14 ka for samples from between 8 and 10.1 m and 1173 ± 22 ka for deeper samples respectively. The palaeomagnetic record of the core shows normal polarity inclinations from the surface to around 9 m followed by reverse polarity inclination and antipodal declinations. The inversion is attributed to the Brunhes-Matuyama transition. 234 U excess ages for the interval corresponding to the part of the core where the polarity inversion occurred are in the range of 735 ± 51 to 794 ± 54 ka, with an arithmetic mean value of 776 ± 14 ka for the B-M transition. This age is in good agreement with that determined previously using other dating methods.

Up to now, the most widely accepted idea of the periglacial environment is that of treeless ecosystems such as the arctic or the alpine tundra, also called the tabula rasa paradigm. However, several palaeoecological studies have recently challenged this idea, that is, treeless environments in periglacial areas where all organisms would have been exterminated near the glacier formed during the Last Glacial Maximum, notably in the Scandinavian mountains. In the Alps, the issue of glacial refugia of trees remains unanswered. Advances in glacier reconstructions show that ice domes did not cover all upper massifs, but glaciers filled valleys. Here, we used fossils of plant and malacofauna from a travertine formation located in a high mountain region to demonstrate that trees (Pinus, Betula) grew with grasses during the Lateglacial-Holocene transition, while the glacier fronts were 200-300 m lower. The geothermal travertine started to accumulate more than 14,500 years ago, but became progressively more meteogene about 11,500 years ago due to a change in groundwater circulation. With trees, land snails (gastropods) associated to woody or open habitats and aquatic mollusc were also present at the onset of the current interglacial, namely the Holocene. The geothermal spring, due to warm water and soil, probably favoured woody glacial ecosystems. This new finding of early tree growth, combined with other scattered proofs of the tree presence before 11,000 years ago in the western Alps, changes our view of the tree distribution in periglacial environments, supporting the notion of tree refugia on nunataks in an ocean of glaciers. Therefore, the tabula rasa paradigm must be revisited because it has important consequences on the global changes, including postglacial plant migrations and biogeochemical cycles., (© 2018 John Wiley & Sons Ltd.)

Valle de Bravo (VB) is the main water reservoir of the Cutzamala hydraulic system, which provides 40% of the drinking water consumed in the Mexico City Metropolitan Area and exhibits symptoms of eutrophication. Nutrient (C, N and P) concentrations were determined in two sediment cores to reconstruct the water column trophic evolution of the reservoir and C fluxes since its creation in 1947. Radiometric methods ((210)Pb and (137)Cs) were used to obtain sediment chronologies, using the presence of pre-reservoir soil layers in one of the cores as an independent chronological marker. Mass accumulation rates ranged from 0.12 to 0.56 g cm(-2) year(-1) and total organic carbon (TOC) fluxes from 122 to 380 g m(-2) year(-1). Total N ranged 4.9-48 g m(-2) year(-1), and total P 0.6-4.2 g m(-2) year(-1). The sedimentary record shows that all three (C, N and P) fluxes increased significantly after 1991, in good agreement with the assessed trophic evolution of VB and with historic and recent real-time measurements. In the recent years (1992-2006), the TOC flux to the bottom of VB (average 250 g m(-2) year(-1), peaks 323 g m(-2) year(-1)) is similar to that found in highly eutrophic reservoirs and impoundments. Over 1/3 of the total C burial since dam construction, circa 70,000 t, has occurred in this recent period. These results highlight the usefulness of the reconstruction of carbon and nutrient fluxes from the sedimentary record to assess carbon burial and its temporal evolution in freshwater ecosystems.

The Sierra de Atapuerca, northern Spain, is known from many prehistoric and palaeontological sites documenting human prehistory in Europe. Three major sites, Gran Dolina, Galería and Sima del Elefante, range in age from the oldest hominin of Western Europe dated to 1.1 to 1.3 Ma (millions of years ago) at Sima del Elefante to c.a. 0.2 Ma on the top of the Galería archaeological sequence. Recently, a chronology based on luminescence methods (Thermoluminescence [TL] and Infrared Stimulated Luminescence [IRSL]) applied to cave sediments was published for the Gran Dolina and Galería sites. The authors proposed for Galería an age of 450 ka (thousands of years ago) for the units lower GIII and GII, suggesting that the human occupation there is younger than the hominid remains of Sima de los Huesos (>530 ka) around 1 km away. In this paper, we present new results obtained by combined Electron Spin Resonance/Uranium-series (ESR/U-series) dating on 20 herbivorous teeth from different levels at the Galería site. They are in agreement with the TL results for the upper part of the stratigraphic sequence (GIV and GIIIb), in the range of between 200 and 250 ka. But for the GIIIa to GIIb levels, the TL ages become abruptly older by 200 ka while ESR ages remain relatively constant. Finally, the TL and ESR data agree in the lowest part of the section (GIIa); both fall in the range of around 350-450 ka. Our results suggest a different interpretation for the GII, GIII and GIV units of Galería and the upper part of Gran Dolina (TD10 and TD11) than obtained by TL. The ESR/U-series results are supported by a Bayesian analysis, which allows a better integration between stratigraphic information and radiometric data., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

(222)Rn has been increasingly used to identify groundwater contribution to surface water. Particular attention has been paid to analytical protocols and counting parameters used for liquid alpha scintillation measurements over a range of activities covering river and groundwater domains. Direct measurements and Rn-extraction protocols are optimized, and scintillometer efficiency is calibrated using international standards over the 0.5-35 Bq/L range. The interval of activities was performed in surface water and groundwater from a small Canadian watershed., (Copyright © 2013. Published by Elsevier Ltd.)

(210)Pb and (137)Cs dating techniques are used to characterise recent peat accumulation rates of two minerotrophic peatlands located in the La Grande Rivière hydrological watershed, in the James Bay region (Canada). Several cores were collected during the summer 2005 in different parts of the two selected peatlands. These minerotrophic patterned peatlands are presently affected by erosion processes, expressed by progressive mechanical destruction of their pools borders. This erosion process is related to a water table rise induced by a regional increase of humidity since the last century. The main objective of the present paper is to (1) evaluate if (210)Pb and (137)Cs dating techniques can be applied to build accurate chronologies in these environments and (2) detect changes in the peat accumulation rates in regard to this amplification of humidity. In both sites, unsupported (210)Pb shows an exponential decreasing according to the depth. Chronologies inferred from (210)Pb allow to reconstruct peat accumulation rates since ca. 1855 AD. The (137)Cs data displayed evident mobility and diffusion, preventing the establishment of any sustained chronology based on these measurements. In the two sites, peat accumulation rates inferred from (210)Pb chronologies fluctuate between 0.005 and 0.038 g cm(-2) yr(-1). As a result, the rise of the water table during the last decade has not yet affected peat accumulation rates.

This paper summarizes the geochemical investigations about the origin and loading history of some trace metals (Ag, Cu and Zn) and nutrients (N and P) in the coastal lagoon complex of Altata-Ensenada del Pabellón, Mexico, by using the radioactive chronometers 210Pb and 228Th and the stable isotopes of C and N. The examination of sediment cores collected at different locations in the lagoon system identified a slight enrichment in metals and nutrients in some points, which was mainly associated to organic matter accumulation. Stable C and N isotope ratios revealed wastewater inputs to the lagoon system and the 210Pb geochronology showed that anthropogenic impact started 50 years ago, with the beginning of the agriculture development and the associated urban growth of the surrounding area. Several atypical 210Pb and 228Th/232Th profiles demonstrated that biological and physical disturbances are common phenomena in these environments, that frequently mask the pollution records; and therefore, considering that the contaminated sediments at some locations in the lagoon system are frequently resuspended and re-oxygenated, the pollutants will continue to be easily remobilized in the food chain.

210Pb geochronology and sediment profiles of carbon, phosphorus and nitrogen were used to study time dependent changes in nutrients fluxes to Culiacan River Estuary. Results indicate that the release of urban sewage and agriculture wastes transported through Culiacan River has produced historically increased carbon, phosphorus and nitrogen fluxes to the study area. C:N:P elemental ratios showed that increments in the nutrients input begins simultaneously for C, N and P in 1948 with the clearing of the catchment for agriculture; although excess of nutrients input increased most importantly around the 1970s to roughly follow the rapidly growing population of Culiacan City. C/N ratios, delta13C and delta15N suggested that nutrient enrichment is mostly influenced by sewage delivered through Culiacan River.