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With advances in commercial space launch capabilities and reduced costs to orbit, humans may arrive on Mars within a decade. Both to preserve any signs of past (and extant) martian life and to protect the health of human crews (and Earth's biosphere), it will be necessary to assess the risk of cross-contamination on the surface, in blown dust, and into the near-subsurface (where exploration and resource-harvesting can be reasonably anticipated). Thus, evaluating for the presence of life and biosignatures may become a critical-path Mars exploration precursor in the not-so-far future, circa 2030. This Special Collection of papers from the Atacama Rover Astrobiology Drilling Studies (ARADS) project describes many of the scientific, technological, and operational issues associated with searching for and identifying biosignatures in an extreme hyperarid region in Chile's Atacama Desert, a well-studied terrestrial Mars analog environment. This paper provides an overview of the ARADS project and discusses in context the five other papers in the ARADS Special Collection, as well as prior ARADS project results.

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Understanding how tropical systems have responded to large-scale climate change, such as glacial-interglacial oscillations, and how human impacts have altered those responses is key to current and future ecology. A sedimentary record recovered from Lake Junín, in the Peruvian Andes (4085 m elevation) spans the last 670,000 years and represents the longest continuous and empirically-dated record of tropical vegetation change to date. Spanning seven glacial-interglacial oscillations, fossil pollen and charcoal recovered from the core showed the general dominance of grasslands, although during the warmest times some Andean forest trees grew above their modern limits near the lake. Fire was very rare until the last 12,000 years, when humans were in the landscape. Here we show that, due to human activity, our present interglacial, the Holocene, has a distinctive vegetation composition and ecological trajectory compared with six previous interglacials. Our data reinforce the view that modern vegetation assemblages of high Andean grasslands and the presence of a defined tree line are aspects of a human-modified landscape.

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Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial-interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles.

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The use of technological means in the process of neuropsychological assessment has been proposed as a technique with promising results in the field of detection of neurocognitive disorders for community-dwelling older adults. Especially during the pandemic period due to COVID-19, telemedicine assumed to be vital in the field of early diagnosis of cognitive disorders and highlighted the clinical utility of remote methods of neuropsychological assessmentby video-conference. This descriptive study presents the development of a remote neuropsychological assessment protocol by selecting appropriate validated tests as part of a more comprehensive evaluation for older adults dwelling in the community. We recruited participants from the Athens Alzheimer's Association center in collaboration with the Hellenic Neuropsychological Society, in Athens, Greece, regarding the period between April 2020 and October 2021. 90 individuals, tested for the first time, were categorized into three groups according to their diagnosis which included: (a) Mild Cognitive Impairment (MCI), (b) Alzheimer's disease, (c) cognitively healthy older adults. The presented protocol outlines the main considerations of a framework about remote neuropsychological assessment, which can maximize the effectiveness of interventions and continuity regarding the care of older adults. The recommendations outlined in the presented protocol highlight strengths and limitations that should be taken into account in remote control procedures. Although the protocol was created in response to pandemic restrictions, tele-neuropsychology shows promise as a way to improve access opportunity to neurodiagnostic services for rural aging and underserved populations, which lack specialized healthcare services. Further application to different populations will add validity to the presented descriptive protocol.

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Palaeoecological records suggest that humans have been in the Andes since at least 14 000 years ago. Early human impacts on Andean ecosystems included an increase in fire activity and the extinction of the Pleistocene megafauna. These changes in Andean ecosystems coincided with rapid climate change as species were migrating upslope in response to deglacial warming. Microrefugia probably played a vital role in the speed and genetic composition of that migration. The period from ca 14 500 to 12 500 years ago was when novel combinations of plant species appeared to form no-analogue assemblages in the Andes. By 12 000 years ago most areas in what are today the Andean grasslands were being burned and modified by human activity. As the vegetation of these highland settings has been modified by human activity for the entirety of the Holocene, they should be regarded as long-term manufactutred landscapes. The sharp tree lines separating Andean forests from grasslands that we see today were probably also created by repeated burning and owe their position more to human-induced fire than climatic constraints. In areas that were readly penetrated by humans on the forested slopes of the Andes, substantial modification and settlement had occurred by the mid-Holocene. In hard-to-reach areas, however, the amount of human modification may always have been minimal, and these slopes can be considered as being close to natural in their vegetation. This article is part of the theme issue 'Tropical forests in the deep human past'.

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ABSTRACT: In Brazil, contamination of raw milk with Mycobacterium tuberculosis complex (MTC) has been reported in several states. The highest rate of consumption of raw milk and its derivatives in Brazil occurs in Amazonas. This state also has the highest prevalence of tuberculosis in both humans and livestock. We assessed the contamination of cow's milk and buffalo's milk with MTC in Amazonas, focusing on Mycobacterium bovis, the species most commonly found in cattle and buffalo. In 2019, 250 samples of raw milk (91 from cattle, 159 from buffalo) were collected before processing from three milk plants in the state of Amazonas. The samples were placed into 21 pools and analyzed using shotgun metagenomic sequencing and taxonomic classification with Kraken 2 and MegaBLAST. To confirm the identity of mycobacterial species found, BLASTN was used to identify specific genomic positions in the TbD1 and RD1 regions and flanking RD4 region. MTC genetic material was identified in all pools of raw milk. Genetic material consistent with M. bovis was identified in seven pools of raw milk (1 from cattle, 6 from buffalo). Buffalo's milk had significantly higher MTC reads than did cow's milk. The common practice of consumption of raw milk and its derivatives in Amazonas presents a risk to public health. Urgent measures to prevent transmission of foodborne tuberculosis are needed in the Amazon region. Greater efforts and resources also should be directed toward elimination of bovine tuberculosis in cattle and buffalo herds in Amazonas and the rest of Brazil.

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In profilometry systems, the conventional optical configuration of fringe projection with the oblique projection and camera axis perpendicular to the field of view requires complicated calculus and exact ray trace designs to get the 3D shape under question accurately. Moreover, when the optical components of the camera and projector and their internal placement are unknown, as is the case with commercial digital video projectors, the correct alignment of these components is uncertain, needing complex methods of calibration to correct the measured shape. In this work, we re-introduce a parallel-optical-axes configuration for a DIY profilometer that simplifies the calibration by a simple trigonometric relationship obtaining the topography with a resolution and accuracy similar to conventional arrangements that require non-simple relationships among phase and height. Furthermore, an experimental method is presented to locate the divergence point within the projector, which allows optimizing the projection and observation distances. The proposed calibration procedure allows proper compensation for the apparent scale change caused by perspective. The performance of the proposed method is tested in an optimized configuration and a non-optimized one, comparing the measurements with a Coordinate-measuring machine. The optimized optical system using simple spatial phase unwrapping shows an improved RMS error of 53µm versus 203µm of the non-optimized.

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Objetivo: Actualizar los resultados del registro BIOBADASAR sobre seguridad, duración y causas de interrupción del tratamiento luego de 8 años de seguimiento. Métodos: BIOBADASAR es un registro de seguridad de terapias biológicas establecido por la Sociedad Argentina de Reumatología. Se presenta la descripción de BIOBADASAR 3.0, una cohorte compuesta por 53 centros de Argentina seguidos prospectivamente desde agosto de 2010 hasta enero de 2018. Resultados: Se registraron 4656 pacientes, 6234 tratamientos [3765 casos (terapia con biológicos) y 2469 controles (terapia no biológicos)]. Se interrumpió el tratamiento en el 44,6% en los casos vs. 27,9% en los controles. Causa principal de discontinuación fue por ineficacia (40% casos vs. 32% controles). Se presentaron 3154 eventos adversos (2230 en casos vs. 924 en controles), de los cuales el 13,6% fueron graves (9,8% en casos y 3,7% en controles). El evento adverso (EA) más frecuente en ambos grupos fueron las infecciones (43,56% en casos vs. 34,31% en los controles, RR: 3,42; IC 95%: 3,02-3,88), y de ellas las de vías aéreas superiores (14,5%). Las neoplasias se presentaron en 78 casos vs. 45 en controles (RR: 1,98; IC 95%: 1,37-2,86). Conclusiones: En este sexto reporte no se observan tendencias diferentes sobre seguridad, duración y causas de interrupción del tratamiento respecto a informes previos. Las infecciones fueron el principal EA y la ineficacia, seguido por EA y la pérdida de pacientes las principales causas de suspensión del tratamiento. El advenimiento de nuevos agentes biológicos y la necesidad de control en seguridad a largo plazo, fortalece el uso de este tipo de registro.

Objective: Update the results of the BIOBADASAR registry on safety, duration and causes of treatment interruption after 8 years of follow-up. Methods: BIOBADASAR is a safety record of biological therapies established by the Argentine Society of Rheumatology. The description of BIOBADASAR 3.0 is presented, a cohort of 53 centers in Argentina followed prospectively from August 2010 to January 2018. Results: 4656 patients were registered, 6234 treatments [3765 cases (therapy with biologicals) and 2469 controls (non-biological therapy)]. Treatment was interrupted in 44.6% in cases vs. 27.9% in controls. Main cause of discontinuation was due to inefficiency (40% cases vs. 32% controls). There were 3154 adverse events (2230 in cases vs. 924 in controls), of which 13.6% were tombs (9.8% in cases and 3.7% in controls). The most frequent adverse event (AE) in both groups were infections (43.56% in cases vs. 34.31% in controls, RR: 3.42, 95% CI: 3.02-3.88), and the upper airway pathways (14.5%). Neoplasms were published in 78 cases versus 45 controls (RR: 1.98, 95% CI: 1.37-2.86). Conclusions: In this article, there are no different trends regarding safety, duration and causes of interruption of treatment compared to previous reports. Infections were the main causes of treatment discontinuation. The advent of new biological agents and the need for control over long-term security, strengthens the use of this type of registration.

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The aims of the present study were to investigate (1) the risk factors that influence the occurrence of clinical ketosis (CK; blood ß-hydroxybutyrate > 3.0 mmol/L) and (2) to determine the influence of subclinical ketosis (SCK; 1.2 ≤ ß-hydroxybutyrate ≤ 2.9 mmol/L) and CK on reproductive performance and milk yield in high-yielding Holstein cows in a hot environment. Cows (n = 345) were blood sampled from 6 to 15 days postpartum for ß-hydroxybutyrate (BHB) determination with a hand-held meter. Cows calving in spring had 3.7 increased odds of having CK (20.7% incidence) than cows calving in summer (3.9% incidence) and autumn (9.4% incidence). Temperature-humidity index < 83 was associated with 1.6 times higher risk for CK compared with cows calving in warmer days. First-service conception rate was 12 and 16 percentage point higher (P < 0.05) in nonketotic cows compared with cows with SCK and CK, respectively. Actual 305-day milk yields for healthy, SCK, and CK cows were 9991 ± 1411, 10,123 ± 1442, and 10,386 ± 1435 kg (mean ± SD), respectively, with no difference (P > 0.05) between groups. In conclusion, this study documented that ketosis was seasonal with lower incidence of this metabolic disease during hot seasons and with increased ambient temperature at calving. Also, 305-day milk yield of Holstein cows was not related to blood BHB content early in lactation in this hot environment. However, elevated circulating BHB was negatively associated with conception rate at first service and fetal losses.

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Oxidation of pyrite (FeS2) plays a significant role in the redox cycling of iron and sulfur on Earth and is the primary cause of acid mine drainage (AMD). It has been established that this process involves multi-step electron-transfer reactions between surface defects and adsorbed O2 and H2O, releasing sulfoxy species (e.g., S2O32-, SO42-) and ferrous iron (Fe2+) to the solution and also producing intermediate by-products, such as hydrogen peroxide (H2O2) and other reactive oxygen species (ROS), however, our understanding of the kinetics of these transient species is still limited. We investigated the kinetics of H2O2 formation in aqueous suspensions of FeS2 microparticles by monitoring, in real time, the H2O2 and dissolved O2 concentration under oxic and anoxic conditions using amperometric microsensors. Additional spectroscopic and structural analyses were done to track the dependencies between the process of FeS2 dissolution and the degradation of H2O2 through the Fenton reaction. Based on our experimental results, we built a kinetic model which explains the observed trend of H2O2, showing that FeS2 dissolution can act as a natural Fenton reagent, influencing the oxidation of third-party species during the long term evolution of geochemical systems, even in oxygen-limited environments.

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El angiomiolipoma renal es un tumor benigno poco frecuente y constituye menos del 2% de todos los tumores renales, teniendo una incidencia de 0.3-3% aproximadamente a nivel mundial. En Venezuela solo existe un reporte de angiomiolipoma, publicado en el 2015. Aunque estos tumores se asocian en un 20% con el complejo de esclerosis tuberosa y la linfangioleiomiomatosis esporádica, pueden presentarse aisladamente con una relación mujer-hombre de 2:1 y más en la 4ª y 5a década de la vida. Presentamos el caso de una mujer de 32 años de edad, quien consultó en 2006 por hematuria macroscópica, dolor en hipogastrio, sin relación con la menstruación; concomitante polaquiuria, astenia y palpitaciones; tuvo episodios recurrentes 3-4 veces/año con transfusión de hemoderivados por anemia severa. En el año 2015 la tomografía mostró "síndrome de cascanueces". La uretrocistoscopia mostró hemorragia activa por uréter derecho, y se realizó nefrectomía parcial derecha cuya biopsia reportó angiomiolipoma renal, con buena evolución y egreso a las 72 horas(AU)

Renal angiomyolipoma is a benign, rare tumor present in less than 2% of all renal tumors; it´s world incidence is 0.3-3%. In Venezuela only one case was reported in 2015. Although these tumors are associated with 20% of the Tuberous Sclerosis, they can present with a gender proportion of 2:1, more often in the 4th and 5th decade. We present here the case of a 32 year- old woman who in 2006 had consulted for hematuria, pelvic pain, weakness and palpitations not related with her menses. These episodes recurred several times per year and she received red blood cell transfusions. In the year 2015 a computerized tomography showed Nutcracker Syndrome and the urethrocystoscopy showed an active bleeding originating in the right urether. A right partial nephrectomy was done and the biopsy was reported as Renal angiomyolipoma. She was discharged 72 hours after her operation(AU)

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Novel chalcone derivatives with different substituents attached to A and B-rings: hydroxyl, methoxyl, geranyl, and prenyl groups were synthesized. The obtained compounds were characterized by NMR, HRMS, UV-Vis, IR, and MS. The theoretical analysis was carried out in all the compounds using density functional theory (DFT) with the B3LYP, PBE0, and M06-2X functionals in combination with the 6-311G(d,p) Pople-type basis set. The excited state properties were calculated by time dependent density functional theory (TD-DFT) using the same methodology applied for the ground state properties. The calculated vertical absorption wavelengths (λmax) in gas phase and in ethanol as a solvent are consistent with the experimental ones, being the TD-DFT:B3LYP/6-311G(d,p) and PCM-TD-DFT:PBE0/6-311G(d,p) the best methodologies for these calculations with good approximation to the experimental values. The calculated reorganization energies indicated that, the four chalcone derivatives present an electron transfer character due to the smaller registered values. From these parameters it is proposed that these show an n-type semiconductor character. The localization of the frontier orbitals (HOMO and LUMO) shows that only the compound containing a hydroxyl group on the A-ring displays a marked delocalization favoring the charge-transfer process in this system. The HOMO-LUMO gap energies indicate that the inclusion of different donor groups in the rings does not improve the obtained values for this property. Graphical Abstract Relationship between spectroscopic and geometrical properties of chalcones were carried out using quantum-chemical calculations and compared with experimental values.

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A novel sensing method is proposed for wavelength scanning interferometry using multiple tunable light sources. As it is well known, a deterioration of depth resolution usually occurs when multiple phase intervals, corresponding to the multiple tunable light sources, are used for distance measurement purposes. It is shown here, that it is possible to regain depth resolution characteristics of a complete scan by means of a temporal phase unwrapping extrapolation method. With the proposed method, the resulting phase differences among multiple phase intervals can be successfully unwrapped to find out the intermediate phase. This effectively allows the application of whole-scan phase sensing for distance measurement using reduced scanning intervals, increased speed, and improved depth detection.

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