Search Results (73)

Since 2014, the Paleoanthropology Group of the National Museum of Natural Sciences (CSIC), in collaboration with Equatoguinean researchers, has been conducting archeo-paleontological fieldwork in Equatorial Guinea, continuing a longstanding Spanish naturalist tradition in this region of West Central Africa. These multidisciplinary investigations, framed within an archeo-paleo-anthropological approach, aim primarily to identify early human occupation in the Central African rainforests. To date, robust evidence of Pleistocene human presence has been documented, particularly through lithic assemblages. Although the scarcity and fragmentation of well-dated sites in Central Africa complicate chronological placement, technological traits observed in the lithic industries recorded in Equatorial Guinea show clear affinities with the African Middle Stone Age (MSA). Complementary taphonomic analyses of faunal remains have been undertaken to better understand bone preservation and fossilization processes under tropical rainforest conditions, thereby contributing to the interpretation of archeological contexts. In parallel, ongoing primatological research within the project—focused on extant primates in their natural habitats—seeks to provide ethological models relevant to the study of hominin locomotor evolution. Notably, the project has led to the ecogeographic characterization of the Engong chimpanzee group in Monte Alén National Park, one of the country’s most pristine protected areas. Full article

Background: Adolescents with a chronological age of less than 15 years or a gynecological age of less than 2 years may have a higher probability of complications because they are more likely to conceive within 1 to 2 years of menarche and, therefore, are still growing and maturing. This could impair their ability to adapt to the physiological demands of pregnancy. Objective: To evaluate the relationship between chronological age and gynecological age with low birth weight and small for gestational age among adolescent mothers in Mexico City. Methods: A retrospective cohort design of adolescent mother–child dyads was conducted. The study followed 1242 adolescents under 19 years of age and their children, collecting data on physical, socioeconomic, and clinical characteristics, including hemoglobin levels. Low birth weight was assessed using the Intergrowth-21st project standards and categorized as above or below 2500 g. The mothers were grouped by chronological age (<15 years and ≥15 years) and gynecological age (<3 years and ≥3 years). Adjusted odds ratios were calculated using binary logistic regression models. The outcome variables were low birth weight and small for gestational age. The independent variables included gynecological age, chronological age, age at menarche, hemoglobin concentration, and gestational weight gain, among others. All independent variables were converted to dummy variables for analysis. Calculations were adjusted for the following variables: marital status, maternal education, occupation, educational lag, family structure, socioeconomic level, pre-pregnancy body mass index, and initiation of prenatal care. Results: The average age of the participants was 15.7 ± 1 years. The frequency of small for gestational age and low birth weight was 20% and 15.3%, respectively. Factors associated with small for gestational age included gynecological age < 3 years [aOR = 2.462, CI 95%; 1.081–5.605 (p = 0.032)], hemoglobin < 11.5 g/dL [aOR = 2.164, CI 95%; 1.08–605 (p = 0.019)], insufficient gestational weight gain [aOR = 1.858, CI 95%; 1.059–3.260 (p = 0.031)], preterm birth [aOR = 1.689, CI 95%; 1.133–2.519 p = 0.01], and living more than 50 km from the care center [aOR = 2.256, CI 95%; 1.263–4.031 (p = 0.006)]. An early age of menarche [aOR = 0.367, CI 95%; 0.182–0.744 (p = 0.005)] showed a protective effect against small for gestational age. Factors associated with low birth weight included gynecological age < 3 years [aOR = 3.799, CI 95%; 1.458–9.725 (p = 0.006)], maternal age < 15 years [aOR = 5.740, CI 95%; 1.343–26.369 (p = 0.019)], preterm birth [aOR = 54.401, CI 95%; 33.887–87.335, p = 0.001], living more than 50 km from the care center [aOR = 1.930, CI 95%; 1.053–3.536 (p = 0.033)], and early age of menarche [aOR = 0.382, CI 95%; 0.173–0.841 (p = 0.017), which demonstrated a protective effect, respectively. Conclusions: The study concludes that biological immaturity, particularly early gynecological age, significantly contributes to adverse birth outcomes during adolescent pregnancies. Interestingly, early menarche appeared to have a protective effect, whereas chronological age was not a significant predictor of small for gestational age. Chronological age has an even greater impact: women younger than 15 years are 5.7 times more likely to have low birth weight infants. However, chronological age did not increase the likelihood of having an SGA newborn. Full article

Background: Human immunodeficiency virus (HIV) remains a global health challenge despite significant advancements in antiretroviral therapy and prevention strategies. Developing a safe and effective vaccine that protects people worldwide has been a major goal, yet the genetic variability and rapid mutation rate of the virus continue to pose substantial challenges. Methods: In this review paper, we aim to provide a comprehensive review of previous vaccine candidates and the progress made in HIV vaccine clinical trials, spanning from the late 1990s to 2025. PubMed and ClinicalTrials.gov were searched for English-language Phase 1–3 HIV vaccine trials published from 1990 to March 2025. After de-duplication, titles/abstracts and then full texts were screened; trial phase, regimen, immunogenicity, efficacy, and correlates were extracted into a structured spreadsheet. Owing to platform heterogeneity, findings were synthesized narratively and arranged chronologically to trace the evolution of vaccine strategies. Results: Early vaccine trials demonstrated that a protein subunit vaccine failed to protect against infection, revealing the complexity of HIV evasion strategies and shifting the focus to a comprehensive immune response, including both antibody and T-cell responses. Trials evaluating the role of viral vectors in generating cell-mediated immunity were also insufficient, and suggested that targeting T cell response alone was not enough. In 2009, the RV144 trial made a breakthrough by showing partial protection against HIV infection and providing the first indication of efficacy. This partial success influenced subsequent trials, prompting researchers to further explore the complex immune response required for protection and consider combinations of vaccine technologies to achieve robust, long-lasting immunity. Conclusion: Despite setbacks, decades of rigorous efforts have provided significant contributions to HIV vaccine discovery and development, offering hope for preventing and protecting against HIV infection. The field remains active by continuing to advance our understanding of the virus, refining vaccine strategies, and employing novel technologies. Full article

This study employs a multidisciplinary approach, integrating geoarchaeology, geomorphology, archaeometry, and palynology to analyze settlement patterns and land use in the surroundings of Capua (southern Italy) during the medieval transition. Borehole sampling and stratigraphic studies indicate significant landscape transformations due to human activity, particularly deforestation and agricultural expansion. Radiocarbon dating confirms settlement activity from antiquity through the early medieval period. Results suggest that Capua’s elevated position provided natural flood protection, influencing its continuous habitation. Pollen analysis reveals a shift from forested landscapes to open pastures, indicating intensive land use. Future research will focus on refining the chronology and archeological context of this transition, further clarifying Capua’s historical and environmental development. Full article

Traditional villages face many difficulties in the era of globalization, especially in light of fast industrialization and urbanization. The breakdown of settlement patterns and the erosion of local characteristics and cultural identities pose critical issues for the sustainable development of these communities. While research on traditional villages and dwellings in core cultural areas is relatively advanced, there remains a significant gap in studies focusing on traditional villages and dwellings in multicultural intermingling regions. By clarifying the characteristics of traditional villages and the cultural landscapes of dwellings under the influence of multiple cultures, as well as their differentiation and underlying mechanisms, this research aims to provide theoretical support for the protective planning of world cultural heritage, which is increasingly characterized by clustering and regionalization. Taking the traditional villages and dwellings in the Jiangxi and Anhui junction area as a case study, we developed a cultural landscape factor system for traditional villages and dwellings across four dimensions: natural environment, spatial configuration, dwelling typology, and historical and cultural context. Using geographic information systems (GIS) zoning methods and statistical spatial analysis, we divided the area into three distinct cultural landscape zones. The findings indicate that the cultural landscapes within each zone exhibit unique regional characteristics at both the village and dwelling levels, particularly in site selection, settlement patterns, and architectural aesthetics. Differentiation across zones is shaped by natural factors, such as topography and water systems, as well as by regional culture, historical migration, the chronological sequence of regional development, commerce and trade growth, and the evolution of administrative systems, alongside broader cultural, economic, and social factors, showing consistent patterns. This study demonstrates that utilizing a scientific and objective zoning approach to accurately identify the cultural landscape characteristics and differentiation patterns across various cultural zones, while clarifying the historical evolution of villages and the transformation of dwelling forms, provides practical insights for cultural landscape zoning in other multicultural regions. Furthermore, it provides scientific guidance to advance China’s rural revitalization strategy and supports the regional protection and sustainable development of world cultural heritage. Full article

Coastal zones, as transition areas for sea/land interaction, have substantial carbon sequestration potential while also being particularly vulnerable to extreme climate. Consequently, it has become essential to evaluate the vegetation carbon sinks in coastal zone areas under extreme climate conditions. In this study, we evaluated the vegetation net ecosystem productivity (NEP) in typical regions within the Yangtze River Delta coastal zone from 2000 to 2020. We studied the regional and chronological properties of NEP and its response to extreme climate. The results revealed the following: (1) Vegetation NEP demonstrated a fluctuating rising trend over the past 21 years, with an interannual change rate of 1.96 gC·m⁻²·a⁻¹, and the 21-year average was 249.22 gC·m⁻²·a⁻¹. Spatially, the southern part of the region had a higher NEP than the northern part, and the northern part had a higher NEP than the central part. (2) The overall area showed characteristics of a vegetation carbon sink, with carbon sink areas accounting for 82.41%. Among the ecosystems, forest ecosystems exhibited the strongest carbon sink capacity, followed by cropland ecosystems, while wetland ecosystems, urban ecosystems, and grassland ecosystems had relatively weaker carbon sink capacities. (3) The overall spatial change trend showed an upward trend, consistent with the temporal trend. There is also a high risk of vegetation NEP degradation in the future. (4) The NEP’s response to extreme temperature was more pronounced. The largest explanatory power was observed with SU25 and TMAX during single-factor analysis. The strongest explanatory power in the interaction analysis was found in the following three factor groups: R99p∩TMAX, SU25∩TNx, and TXx∩LST. The results highlight a complex synergistic interplay among these influences on NEP. The findings offer a scientific basis for ecological protection and the attainment of dual-carbon goals in the coastal zone of the Yangtze River Delta. Full article

The response of trees to climate is crucial for the health assessment and protection of forests in alpine regions. Based on samples of Pinus tabuliformis and Abies fargesii, two typical evergreen coniferous species with distinct elevation differences in the vertical vegetation zones of the Qinling Mountains, we have developed two tree-ring width chronologies for the southern slope of the central Qinling Mountains in central China. The correlation analysis results showed that the radial growth of P. tabuliformis and A. fargesii responded to different climatic factors. Water stress caused by temperature in May of the current year was the main limiting factor for radial growth of P. tabuliformis, while precipitation in September of the previous year and the current year had a negative impact on A. fargesii, with lag effects of temperature and precipitation during the previous growing season. Spatial correlation and comparative analysis indicated that the P. tabuliformis chronology responded to extreme dry and wet events on a regional scale. Interannual and multidecadal periodic signals recorded by tree rings suggested that the hydrological and climatic changes on the southern slope of the central Qinling Mountains were teleconnected with the Pacific and Atlantic Oceans, including El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO). Our results provide new evidence for a hydroclimatical response study inferred from tree rings on the southern slope of the central Qinling Mountains. Full article

Polyphenols are powerful natural antioxidants with numerous biological activities. They change cell membrane permeability, interact with receptors, intracellular enzymes, and cell membrane transporters, and quench reactive oxygen species (ROS). Yarrowia lipolytica yeast, being similar to mammalian cells, can be used as a model to study their survival ability upon long-lasting cultivation, assaying the effect of dihydroquercetin polyphenol (DHQ). The complex assessment of the physiological features of the population assaying cell respiration, survival, ROS detection, and flow cytometry was used. Y. lipolytica showed signs of chronological aging by eight weeks of growth, namely a decrease in the cell number, and size, increased ROS generation, a decrease in colony-forming unit (CFU) and metabolic activity, and decreased respiratory rate and membrane potential. An amount of 150 µM DHQ decreased ROS generation at the 6-week growth stage upon adding an oxidant of 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH). Moreover, it decreased CFU at 1–4 weeks of cultivation, inhibited cell metabolic activity of the 24-h-old culture and stimulated that on 14–56 days of growth, induced the cell respiration rate in the 24-h-old culture, and blocked alternative mitochondrial oxidase at growth late stages. DHQ serves as a mild pro-oxidant on the first day of age-stimulating anti-stress protection. In the deep stationary stage, it can act as a powerful antioxidant, stabilizing cell redox status and reducing free radical oxidation in mitochondria. It provides a stable state of population. The hormetic effects of DHQ using lower eukaryotes of Y. lipolytica have been previously discussed, which can be used as a model organism for screening geroprotective compounds of natural origin. Full article

The present study contributes to the morphogenesis of the Miresii Cave, located in Cheia Mare of Dâmbovița in the area of the Bran—Dragoslavele Corridor, an important tourist axis in Romania. The main aim of the research is the proposal to the Scientific Council of Piatra Craiului National Park to bring to the attention of the national decision-making commissions that the cave be declared a natural monument. The inventory of this speleological geomorphosite suggested its inclusion in a thematic geotouristic circuit integrated into national and EU-protected natural areas. The novelty of the present research lies in the fact that the cave has never been studied before, being difficult to access. This cave, spatially found in the strict protection zone of the national park, is not included in its management plan. When being integrated into other nature protection areas, it is necessary to exclude any form of recreational tourism so that the cave can be exploited as a geotouristic resource strictly for research and educational purposes. The morphogenetic analysis of the cave, based on the information synthesized from geomorphological and geological literature, allowed us to decipher the morphological individualization of Miresii Cave in the local and regional geocronomorphological context, in accordance with the chronological separation of the karstification phenomenon manifested first in phreatic and later in vadose karst. The diversified typology of speleothems has been rendered according to the geomorphologic generating processes. The identification of the Rhinolophus ferrumequinum chiropteran colony and observations of its biotope highlighted the ecological significance of the cave. The inventory of the individuals of the colony led to the conclusion that the cave harbors one of the first two largest bat communities of this species in the national park and the adjacent depressional corridor. The present study may allow the documentation of the photographs and description of the geomorphosite integrated into the proposed thematic circuit to be included on billboards and in promotional brochures. Thus, it could also be useful for the decision-making authorities of Rucar and Podu Dâmboviței villages, which are interested in making decisions related to the promotion of geotourism, especially due to the existence of numerous geological and geomorphological tourist resources in the administrative territories. Full article

This study presents a comprehensive palaeoenvironmental reconstruction of the southern part of the Danube–Tisza interfluve in the Carpathian Basin from the Late Pleistocene to Early Holocene, addressing the region’s response to global climate forcings and local environmental factors based on multi-proxy analyses of two key protected areas: the Katymár brickyard and the hay meadows and loess banks of Hajós. By integrating radiocarbon-dated malacological, macrobotanical, pollen, phytolith, geochemical, and sedimentological analyses, it was possible to provide a picture of past climate–ecosystem interactions. The Katymár North sequence provides an extended chronology from Marine Isotope Stage 3 (MIS3, ca. 36,000 cal BP) through the Last Glacial Maximum (LGM) and into the Early Holocene, while the Hajós sequence offers high-resolution data for the LGM–Holocene transition. By the late Ice Age, humidity and surface moisture superseded temperature as primary palaeoecological limiting factors, promoting ecotone-like forest–steppe environments during cooling periods. Full article

In recent years, increasing urbanization has profoundly impacted the quality of regional habitats, presenting a severe risk to the ability of a region to develop in a high-quality manner. Therefore, the scientific assessment of the features of habitat quality (HQ) evolution over time and space and the prediction of future trends in changes in the HQ are of great significance for the formulation of effective ecological protection policies. Based on five periods of land use and land cover (LULC) data from 2000 to 2020, InVEST model was used to estimate both geographical and chronological trends in the HQ in the Tuha region, China. Spatial autocorrelation analysis methods were used to assess HQ and spatial aggregation of habitat degradation, and ecological zoning was delineated in conjunction with the Human Footprint Index (HFI). Based on the results of ecological zoning, the study predicted changes in habitat quality (HQ) in 2040 under three scenarios: natural development (ND), ecological preservation (EP), and urban development (UD) by applying the Patch-Generating Land Use Simulation (PLUS) model. The results demonstrated that (1) from 2000 to 2020, the habitat quality in the Tuha region exhibited a downward trend, with the proportion of low HQ increasing from 83.63% to 84.24%. Spatially, high habitat quality (HQ) is mainly concentrated in the Tianshan Mountains. From 2000 to 2020, the Moran index for habitat quality (HQ) decreased from 0.967 to 0.959, while the Moran index for habitat degradation declined from 0.805 to 0.780. The habitat quality (HQ) and degradation exhibit significant spatial aggregation, and the degree of degradation has increased incrementally. (2) From 2000 to 2020, human activities in the Tuha area increased continuously and were mainly concentrated in Tuha district and counties. The proportion of high Human Footprint Index (HFI) increased from 0.66% to 1.32%, while the proportion of medium HFI increased from 3.13% to 7.46%. (3) The expansion of urbanized land has exacerbated habitat degradation. The proportion of high HQ in the EP scenario is higher than that in ND and UD scenario. The results show that the ecological protection scenario is more conducive to the sustainable development of habitat quality in the Tuha region. The results can provide a scientific basis for ecological management and protection in the Tuha area. Full article

Tinospora Miers is considered a valuable medicinal herb that is suffering from severe habitat degradation due to climate change and human activities, but the variations in its suitable habitats and ecological service values remain unclear, especially in the context of accelerating global warming. In this study, we employed the MaxEnt model to estimate the suitable habitat changes and ecological service values of three rare Tinospora (T. craveniana, T. yunnanensis, and T. sinensis) species in China under four climate change scenarios (SSP126, SSP245, SSP370, and SSP585) from 2041 to 2100. The results show that the suitable habitats of T. craveniana, T. yunnanensis, and T. sinensis are mainly distributed in Sichuan, Yunnan, and Guangxi, respectively. Under the future climate scenarios, the suitable habitat of T. craveniana and T. sinensis is projected to expand toward the northeast and north, while that of T. yunnanensis will contract toward the northeast. The mean diurnal temperature range is the main environmental factor affecting T. craveniana and T. yunnanensis, while the annual mean temperature is a more important factor affecting T. sinensis. In the SSP245 scenario, T. craveniana and T. yunnanensis are expected to have the highest ecological service values from 2081 to 2100, while they will be relatively consistent in other climate scenarios and chronologies. The case of water protection accounts for the highest proportion of the total ecosystem service values, except for the economic value. This study provides a scientific reference for the diversity conservation of these rare species. Full article

Historical lime mortars provide valuable information on the construction phases of buildings and allow reconstruction of the chronology of the historical structures. The City Wall of Burgos and the Mudejar Arch of San Martin were declared an Asset of Cultural Interest and have been protected since 1949. Several restorations at the end of the 20th century altered the original appearance of the wall and the current gate, making it difficult to establish stratigraphic relationships between the two structures. Given the scarcity of information on the construction phases of the wall and the uncertainty of the historical dates, a mineralogical and chemical characterization of the mortars was carried out, and the suitability of the binder for radiocarbon dating was assessed. The petrographic, mineralogical and chemical analyses of the lime mortars from the Arc of San Matin show distinctive characteristics, suggesting different construction periods and production processes, where the selection of raw materials and production methods was conducted according to the construction requirements. Moreover, the presence of contaminant phases and microparticles of charcoal in the binder fraction led to discard all the samples for mortar radiocarbon dating. Full article

As a consequence of the spacetime structure, defined by the tetrad field instead of the metric tensor alone, $f\left(T\right)$ gravity seems to harbor its own chronology protection agency. When Gott’s pair of moving cosmic strings is considered, it is shown that the requirement of having a global parallelization—i.e., a global smooth field of tetrads– drastically restricts the form of the tetrads on the junction surface between the two strings. The junction conditions on the tetrad field are satisfied only if the corresponding boosts needed to put the strings in motion are null on the matching surface. This seems to throw overboard Gott’s construction from the outset without the need for analyzing the divergence of the expectation value of the energy–momentum tensor on the Cauchy horizon, evading in this way bothersome quarrels concerning the choice of vacuum. Full article

Underwater cultural heritage (UCH) is a diverse and valuable resource that includes shipwrecks, sunken cities, and other submerged archaeological sites. It is an important part of human history and culture and can significantly benefit society. However, various factors often neglect and threaten UCH, including climate change, pollution, and human activities. Several factors, including technological advances, the development of international law, and the growing awareness of the importance of cultural heritage, have influenced the evolution of the concept of UCH. In the early days of underwater archaeology, the focus was on recovering artifacts and treasures from shipwrecks. However, over time, there has been a shift towards a more holistic approach to the management of UCH, which emphasizes the importance of in situ preservation and the involvement of local communities. This review provides a chronological analysis of the evolution of the concept of UCH over the past 70 years and examines the main international conventions and charters developed to protect UCH. The review also discusses the relationship between UCH and marine protected areas (MPAs), the marine environment, and the coastal landscape. Full article