Independent age estimates resolve the controversy of ancient human footprints at White Sands.

Human footprints at White Sands National Park, New Mexico, USA, reportedly date to between ~23,000 and 21,000 years ago according to radiocarbon dating of seeds from the aquatic plant Ruppia cirrhosa. These ages remain controversial because of potential old carbon reservoir effects that could compromise their accuracy. We present new calibrated 14C ages of terrestrial pollen collected from the same stratigraphic horizons as those of the Ruppia seeds, along with optically stimulated luminescence ages of sediments from within the human footprint-bearing sequence, to evaluate the veracity of the seed ages. The results show that the chronologic framework originally established for the White Sands footprints is robust and reaffirm that humans were present in North America during the Last Glacial Maximum.

Albertania and Egbenema gen. nov. from Nigeria and the United States, expanding biodiversity in the Oculatellaceae (cyanobacteria).

Knowledge of the tropical terrestrial cyanobacterial flora from the African continent is still limited. Of 31 strains isolated from soil and subaerial samples collected in Lagos State, Nigeria, three were found to be in the Oculatellaceae, including two species in a new genus. Subsequently, isolates from microbial mats in White Sands National Park in New Mexico, United States, and from a rock near the ocean in Puerto Rico, United States, were found to belong to the new genus as well. Cyanobacterial isolates were characterized microscopically, sequenced for the 16S rRNA gene and associated ITS region, and phylogenetically analyzed. Egbenema gen. nov., with three new species, as well as two new species of Albertania were differentiated from all other Oculatellaceae. Both genera belong to a supported clade within the Oculatellaceae that includes Trichotorquatus and Komarkovaea. The two new species of Albertania, A. egbensis and A. latericola, were from the same sample, but were evolutionarily separate based on 16S rRNA gene phylogenies, percent identity below the 98.7% threshold, and ITS rRNA percent dissimilarity >7.0%. Egbenema aeruginosum gen. et sp. nov. was phylogenetically separated from Trichotorquatus and Albertania but was in a clade with other strains belonging to Egbenema. The two Egbenema strains from the United States are here named Egbenema epilithicum sp. nov. and Egbenema gypsiphilum sp. nov. Our results support the hypothesis that further species discoveries of novel cyanobacteria will likely be made in soils and subaerial habitats, as these habitats continue to be studied, both in tropical and temperate biomes.

Biocrust carbon exchange varies with crust type and time on Chihuahuan Desert gypsum soils.

Introduction: In dryland systems, biological soil crusts (biocrusts) can occupy large areas of plant interspaces, where they fix carbon following rain. Although distinct biocrust types contain different dominant photoautotrophs, few studies to date have documented carbon exchange over time from various biocrust types. This is especially true for gypsum soils. Our objective was to assess the carbon exchange of biocrust types established at the world's largest gypsum dune field at White Sands National Park. Methods: We sampled five different biocrust types from a sand sheet location in three different years and seasons (summer 2020, fall 2021, and winter 2022) for carbon exchange measurements in controlled lab conditions. Biocrusts were rehydrated to full saturation and light incubated for 30 min, 2, 6, 12, 24, and 36 h. Samples were then subject to a 12-point light regime with a LI-6400XT photosynthesis system to determine carbon exchange. Results: Biocrust carbon exchange values differed by biocrust type, by incubation time since wetting, and by date of field sampling. Lichens and mosses had higher gross and net carbon fixation rates than dark and light cyanobacterial crusts. High respiration rates were found after 0.5 h and 2 h incubation times as communities recovered from desiccation, leveling off after 6 h incubation. Net carbon fixation of all types increased with longer incubation time, primarily as a result of decreasing respiration, which suggests rapid recovery of biocrust photosynthesis across types. However, net carbon fixation rates varied from year to year, likely as a product of time since the last rain event and environmental conditions preceding collection, with moss crusts being most sensitive to environmental stress at our study sites. Discussion: Given the complexity of patterns discovered in our study, it is especially important to consider a multitude of factors when comparing biocrust carbon exchange rates across studies. Understanding the dynamics of biocrust carbon fixation in distinct crust types will enable greater precision of carbon cycling models and improved forecasting of impacts of global climate change on dryland carbon cycling and ecosystem functioning.

Response to Comment on "Evidence of humans in North America during the Last Glacial Maximum".

Madsen et al. question the reliability of calibrated radiocarbon ages associated with human footprints discovered recently in White Sands National Park, New Mexico, USA. On the basis of the geologic, hydrologic, stratigraphic, and chronologic evidence, we maintain that the ages are robust and conclude that the footprints date to between ~23,000 and 21,000 years ago.Madsen et al. (1) question the veracity of calibrated radiocarbon ages used to constrain the antiquity of human trackways discovered recently at White Sands National Park (WHSA) Locality 2, New Mexico, USA (2). The ages were derived from seeds of the aquatic plant Ruppia cirrhosa, which they suggest may suffer from hard-water (or reservoir) effects, making them too old, potentially by thousands of years. We were well aware of this possibility, investigated it, and presented several lines of evidence that argued against such a problem. Here we respond to each of their four primary points.

Chronic wound healing by controlled release of chitosan hydrogels loaded with silver nanoparticles and calendula extract.

As the skin is the main protective organ of the body, it is exposed to wounds or injuries which carry out a healing process during a period of approximately 15 days depending on the severity of the injury. In the present research, the development of chitosan-based hydrogels loaded with silver nanoparticles and calendula extract (Ch-AgNPs-Ce) was proposed. This can be used to fulfill the hemostatic, anti-infective, antibacterial, healing and anti-inflammatory functions through controlled release of the nanoparticles and calendula extract in substitution of commonly used drugs. The physical properties of the silver nanoparticles were analyzed by UV-visible spectroscopy, scanning and transmission electron microscopy, showing a size between 50 and 100 nm. The antibacterial properties were evaluated by the agar well diffusion method. Antimicrobial testing of the hydrogels showed that the inclusion of silver nanoparticles provides concentration-dependent antibacterial behavior against E. coli and S. aureus. The healing properties of the system were tested in two diabetic patients to whom said hydrogels were placed, obtaining a positive curative result after a few weeks. Therefore, it can be concluded that Ch-AgNPs-Ce hydrogels can achieve healing in chronic or exposed wounds after a period of time which can be used in alternative treatments in patients with poor healing capacity.

Evidence of humans in North America during the Last Glacial Maximum.

Archaeologists and researchers in allied fields have long sought to understand human colonization of North America. Questions remain about when and how people migrated, where they originated, and how their arrival affected the established fauna and landscape. Here, we present evidence from excavated surfaces in White Sands National Park (New Mexico, United States), where multiple in situ human footprints are stratigraphically constrained and bracketed by seed layers that yield calibrated radiocarbon ages between ~23 and 21 thousand years ago. These findings confirm the presence of humans in North America during the Last Glacial Maximum, adding evidence to the antiquity of human colonization of the Americas and providing a temporal range extension for the coexistence of early inhabitants and Pleistocene megafauna.

3-D radar imaging unlocks the untapped behavioral and biomechanical archive of Pleistocene ghost tracks.

Footprint evidence of human-megafauna interactions remains extremely rare in the archaeological and palaeontological records. Recent work suggests ancient playa environments may hold such evidence, though the prints may not be visible. These so-called "ghost tracks" comprise a rich archive of biomechanical and behavioral data that remains mostly unexplored. Here we present evidence for the successful detection and 3-D imaging of such footprints via ground-penetrating radar (GPR), including co-associated mammoth and human prints. Using GPR we have found that track density and faunal diversity may be much greater than realized by the unaided human eye. Our data further suggests that detectable subsurface consolidation below mammoth tracks correlates with typical plantar pressure patterns from extant elephants. This opens future potential for more sophisticated biomechanical studies on the footprints of other extinct land vertebrates. Our approach allows rapid detection and documentation of footprints while enhancing the data available from these fossil archives.

Footprints preserve terminal Pleistocene hunt? Human-sloth interactions in North America.

Predator-prey interactions revealed by vertebrate trace fossils are extremely rare. We present footprint evidence from White Sands National Monument in New Mexico for the association of sloth and human trackways. Geologically, the sloth and human trackways were made contemporaneously, and the sloth trackways show evidence of evasion and defensive behavior when associated with human tracks. Behavioral inferences from these trackways indicate prey selection and suggest that humans were harassing, stalking, and/or hunting the now-extinct giant ground sloth in the terminal Pleistocene.

Latino church leaders' perspectives on childhood obesity prevention.

BACKGROUND: The prevalence of obesity among Latino children is an increasing concern. Churches are settings that a majority of Latino families frequent on a regular basis. In addition to religious worship, churches supply social, emotional, and material support. Therefore, churches may be promising venues for obesity-prevention interventions engaging families and communities. PURPOSE: To qualitatively examine Latino church leaders' perspectives on childhood obesity and insights on obesity-prevention programming in faith-based community settings in South Texas. METHODS: In-depth interviews were conducted between 2009 and 2011 with a purposive sample of 35 Latino church leaders from 18 churches in San Antonio, Texas. Interviews were audiotaped and transcribed verbatim. Inductive analysis was performed to identify themes. RESULTS: The results revealed that participants were knowledgeable about the severity and health consequences of childhood obesity, and the extent to which it was affecting members of their congregations. Participants discussed the interconnection between one's faith and health (i.e., one's body as "God's Temple"). They suggested that churches could serve as a conduit for obesity-prevention programs that offer faith-oriented health education, cooking classes, and fun physical activity opportunities for both parents and children. CONCLUSIONS: This study reveals the strong potential of faith-based communities to serve as an intervention setting with the needed infrastructure for implementing effective obesity-prevention strategies.

Efecto de suplementar cerdas con vitaminas y aminoácidos en gestación y lactancia sobre los parámetros productivos de la granja porcícola la Mejorana / The effect of supplementing sows with aminoacids in their gestation and lactation period under productive parameters at

En este estudio se suplementaron cerdas con aminoácidos y vitaminas durante el último tercio de gestación y la lactancia para evaluar la respuesta sobre algunos parámetros reproductivos de la cerda. El estudio se realizó en una granja porcina localizada en el municipio de San Antonio del Tequendama con cerdas de la línea Dekalb. Se trabajó con dos grupos de animales cada uno compuesto por 30 cerdas seleccionadas y tratadas de la siguiente forma: Grupo experimental 1, al día 85 de gestación se le administró 3ml de Vitacalier vía intramuscular, al mismo tiempo que se le comenzó la administración de 5 gr diarios de Promocalier en el concentrado hasta el destete y 5ml de Robavit vía intramuscular al comienzo del parto; el grupo control 2, no recibió tratamiento. Se evaluaron los siguientes parámetros: a. Peso de la camada al nacimiento, b. Peso de la camada al destete, c. Nacidos muertos, d. Ganancia de pesos, e. Días de lactancia. En lo que respecta a los parámetros a, b, c, y d, no hubo diferencias significativas entre grupos; los resultados fueron: a. Con un peso de 1.52 y 1.40 Kg para los grupos 1 y 2 respectivamente; el parámetro b. Con valores de 5.97 Kg (grupo1) y (6.27 Kg (grupo2); el parámetro c. Nacidos muertos 1.83 lechones (grupo1) y 2.17 lechones (grupo 2); en lo que respecta al parámetro d. Los resultados obtenidos fueron de 0.2441 Kg (grupo 1) y 0.2399 Kg (grupo 2); a diferencia de los parámetros anteriores el parámetro e. reveló una diferencia significativa (p<0.05) entre grupos (18.6 días grupo 1 y 20.2 días grupo 2.) A diferencia del análisis estadístico el estudio representa ganancias económicas para el productor por el aumento de los kilogramos producidos y disminución de los días de lactancia, siendo rentable el uso de suplementos en granjas con estas características...