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One of the most important current challenges for ecologists is to evaluate how human-induced changes in ecosystems would impact viability of populations. Demographic response to anthropogenic impact could help us to understand how to manage those impacts. Using demographic techniques and population projection models, here we assess if demography and population dynamics of the tree Prosopis flexuosa change in cattle grazed areas compared to ungrazed areas in the Central Monte desert, Mendoza, Argentina. To this end, we quantified vital rates and constructed a population projection matrix model to compare the deterministic population growth rate ( λ ) between grazed and ungrazed areas. We also estimated elasticities of vital rates to evaluate their potential importance for future changes in λ and performed a life table response experiment (LTRE) to identify the life cycle transitions that contribute the most to the observed differences in λ between the two treatments. Although we found differences in demographic processes, such as lower seed production and higher probability of reversion to smaller size classes in young individuals when cattle were present, our results indicate that cattle grazing had no significant effect on λ for this species. According to the elasticity analysis, survival of large trees is the main driver of the population growth rate ( λ ) of P. flexuosa , and the vital rates related to tree reproduction, such as seed production and germination, have a poor contribution to λ . Therefore, limitations of activities that can affect survival of large trees should be considered as part of the conservation strategy for this species. Our study provides a compilation of demographic information that can be useful to set policies connecting the conservation objectives for this woodlands with that of ranch managers of the area. [ABSTRACT FROM AUTHOR]

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Abstract: The correlation dimension D 2 yields good results in several biomedical fields. Nonetheless, no clinical application to electromyography has been developed yet. One reason is the high electromagnetic noise typical of clinical environments. This noise is characterized by sharp spectral lines of variable intensity and frequency. The filtering techniques commonly implemented in electromyographs can efficiently deal with this kind of noise. They allow a safe estimate of linear quantities like the root mean square (r.m.s.) or the median frequency (MF). Their performance is not as good for nonlinear purposes. The filters may modify the nonlinear properties of the signal, leading to unacceptable estimates of D 2. We consider a simple procedure based on a modified Wiener filter. Its performance is compared with that from a bandpass followed by multiple notch filters. Our procedure leads to a gain in precision and accuracy when estimating D 2. The two filtering approaches are also compared with respect to a biomedical application proposed by others. Using data from 12 healthy subjects, the modified Wiener procedure raises the percentage of successes in that application from 17% to 83%. New experimental data suggest D 2 carries information not carried by r.m.s. or MF. [Copyright &y& Elsevier]

Objectif discuter et illustrer les signes de torsion d’annexe en IRM dans la population pédiatrique. Evaluer son intérêt. Matériels et méthodes étude rétrospective de 19 cas, d’âge moyen 13 ans, opérés après diagnostic de torsion d’annexe à l’IRM. Relecture des données cliniques, échographiques, des IRM, des comptes-rendus opératoires, histologiques et comparaison des deux groupes. Résultats le diagnostic de torsion à l’IRM a été confirmé en chirurgie dans 13 cas, dont 2 étaient des torsions tubaires isolées. 6 cas étaient des faux positifs de torsion en IRM dont 4 kystes hémorragiques de l’ovaire, une péritonite appendiculaire associée à un kyste ovarien, et un ovaire normal. L’IRM a redressé le diagnostic de torsion, non vu en échographie dans 8 cas dont 3 ovaires ont pu être sauvés par détorsion. Les signes IRM les plus fréquents en cas de torsion étaient les signes tubaires (oedème, tour de spire) et les signes d’ischémie. L’hémorragie intraovarienne en cas de torsion était corrélée en anatomopathologie à de l’infarcissement hémorragique. 38% des torsions étaient associées à une masse ovarienne. Conclusion l’IRM réalisée en urgence présente un intérêt diagnostic et pronostic dans les suspicions de torsion d’annexe en pratique pédiatrique. [ABSTRACT FROM AUTHOR]

The reconstruction of glacial paleolake formation and evolution allows the understanding of glacier advance and retreat behavior for longer periods of time. New datings obtained from paleolacustrine deposits in the Argentinian Patagonian Andes (Northwestern region of Santa Cruz Province) reveal that glacial lakes formed before the Last Glacial Maximum, they being as old as 31,278 cal yr BP, and evolved until 6900 cal yr BP. The interpretation of stratigraphic profiles described in different sectors of the Perito Moreno National Park (PMNP) allows reconstructing lacustrine, glaciolacustrine, glacial till and delta paleoenvironments. In each sector, organic-rich sediments were also sampled to obtain four absolute ages through AMS methodology. Thus, the paleogeographic reconstructions proposed are based on paleobathymetries performed from digital elevation models, datings and facies distribution of lacustrine deposits (mainly composed of laminated silts with subordinated sands and muds). Based on these new data, the paleogeography of this area is characterized by two lakes at 880 m.a.s.l at 31,200 ca yr BP, one directly related to modern Belgrano lake, while the other is probably related to the Burmeister lake but more than 10 km toward the East as respect to its current position. The paleogeography reconstruction shows, between 11,731 cal yr BP and 10,819 cal yr BP, the existence of a major paleolake at 900-920 m.a.s.l. which was connected to several modern lakes. Finally, a decrease of the paleolake level between 900 and 890 m.a.s.l. was recorded at 6900 cal yr BP which produced two major lacustrine systems separated by moraine deposits. [ABSTRACT FROM AUTHOR]

We discuss the use of obsidian as a tool to understand the mobility range of hunter-gatherers living in a high-elevation desert in the Salt Puna, specifically in the area of Antofagasta de la Sierra, Catamarca, between ca. 9000 and 6000 BP. XRF analyses of a vertical sample of obsidian artifacts pertaining to Early and Middle Holocene contexts from three archaeological sites show the use of various sources within a range of 40–95 km respectively from the study area. Our analyses suggest that mobility patterns during the early colonization phase (Early Holocene) of this high elevation region included two sources located in the eastern and northwestern areas of the Salt Puna and reveal a process of landscape learning. By contrast, during the phase of effective occupation (Middle Holocene) —a period coinciding with climatic fluctuations and decreasing rainfall—a greater number of obsidian sources were used suggesting increased knowledge of the landscape as well as a pattern of territorial range shifting. [ABSTRACT FROM AUTHOR]

The Pueyrredón-Posadas-Salitroso lacustrine system (PPS-LS) is located in the Andean Patagonia region of Argentina (47°22′28″S – 71°55′34″W) and represents a series of lakes formed as glaciers retreated during the late Pleistocene and early Holocene. These lakes began as proglacial lakes and later evolved into periglacial lakes. This research presents the chronological evolution of the PPS-LS bathymetric variations based on the analysis of stratigraphic profiles surveyed at different locations and the dates obtained from lake sediments. Four paleogeographic sketches representing the chronological evolution of the PPS-LS between 23,580 BP and 5208 BP have been developed based on the integration of these data. [ABSTRACT FROM AUTHOR]

Paleoenvironmental records in the eastern Andes (16–26° S), broadly indicate a gradual trend towards aridity from the Early to the Middle Holocene with certain chronological discrepancies. Even under this adverse climatic scenario, the archaeological record suggests the presence of hunter-gatherers in the southern Argentinian Puna associated with the availability of resources for their subsistence, even during drier than present periods. Herbivore coprolites contain multiple proxies that provide independent records of paleovegetation and paleoenvironments. Among them, plant tissue fragments and pollen grains, offer a powerful and complementary insight on past vegetation changes and their relationship with climatic conditions during the Holocene, particularly in the southern Argentine Puna. Thus, in this work camelid coprolites recovered from the archaeological site Quebrada Seca 3 (QS3) were analyzed using microhistological and palynological techniques to reconstruct the diet of these herbivores but also to infer vegetation and environmental changes from the Early to Middle Holocene (ca. 9600–6100 cal yrs BP) in the southern Argentine Puna (26°S). Results of both records show similar patterns in the percentages and species richness (especially those growing in wetlands) within and between coprolites dating to the Early Holocene (9600-8000 cal yrs BP) which suggest an environmental stability during this period. Around 8000 cal yrs BP, an increased variability in the richness of grasses, shrubs, dwarf shrubs, annual herbs and sedges species shows the gradual establishment of dry conditions, peaking around 6100 cal yrs BP. By this time, variability in the plant content of coprolites reflects seasonality in the assemblages due to the presence/absence of annual herbs either in the pollen or microfragment records. Therefore, it is likely that coprolites were from different animals that were hunted at different times of the year, supporting the evidence that QS3 has been occupied for short intervals of time after 7200 cal yrs BP when environmental conditions were extremely arid. The complementary analysis of the microfragments and pollen records preserved in coprolites provide valuable, complementary and alternative archive for herbivorous diet and for vegetation and environmental reconstructions, reinforcing that multiproxy approaches are necessary to obtain maximum information from coprolite studies. • Microhistological and palynological analysis of coprolites show paleovegetation changes. • Changes in the record were evidenced at ca. 8000 cal yrs BP when dry conditions began. • Palynological record indicate seasonal assemblages at ca. 6100 cal yrs BP. • During the extreme dry period of the Middle Holocene, QS3 was temporarily occupied. • Paleoenvironmental inferences from coprolites improve records at local and regional scales. [ABSTRACT FROM AUTHOR]

Abstract: Management of cystic lymphangioma necessitate for optimal diagnosis and treatment the expertise of a trained multidisciplinary team including dermatologists, radiologists, plastic and vascular surgeons. An initial imaging work-up of these lesions by ultrasound Doppler examination and MR imaging are necessary before treatment planning. Depending of the size, the location, the risk for the adjacent organs, a therapeutic decision may be mandatory. Percutaneous sclerotherapy is a safe and efficient treatment. It is the treatment of choice that must be proposed in first intention. [Copyright &y& Elsevier]

[Display omitted] Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) shows potent preclinical anticancer activity in pediatric solid tumors such as Ewing sarcoma, rhabdomyosarcoma and neuroblastoma, but responses in clinical trials have been modest. In this work, we aimed to discover a rational biomarker-based approach to select the right candidate patients for this treatment. We assessed the efficacy of nab-paclitaxel in 27 patient-derived xenografts (PDX), including 14 Ewing sarcomas, five rhabdomyosarcomas and several other pediatric solid tumors. Response rate (partial or complete response) was remarkable in rhabdomyosarcomas (four of five) and Ewing sarcomas (four of 14). We addressed several predictive factors of response to nab-paclitaxel such as the expression of the secreted protein acidic and rich in cysteine (SPARC), chromosomal stability of cancer cells and expression of antiapoptotic members of the B-cell lymphoma-2 (Bcl-2) family of proteins such as Bcl-2, Bcl-xL, Bcl-W and Mcl-1. Protein (immunoblotting) and gene expression of SPARC correlated positively, while immunoblotting and immunohistochemistry expression of Bcl-2 correlated negatively with the efficacy of nab-paclitaxel in Ewing sarcoma PDX. The negative correlation of Bcl-2 immunoblotting signal and activity was especially robust (r = 0.8352; P = 0.0007; Pearson correlation). Consequently, we evaluated pharmacological strategies to inhibit Bcl-2 during nab-paclitaxel treatment. We observed that the Bcl-2 inhibitor venetoclax improved the activity of nab-paclitaxel in highly resistant Bcl-2-expressing Ewing sarcoma PDX. Overall, our results suggest that low Bcl-2 expression could be used to select patients with Ewing sarcoma sensitive to nab-paclitaxel, and Bcl-2 inhibitors could improve the activity of this drug in Bcl-2-expressing Ewing sarcoma. [ABSTRACT FROM AUTHOR]

In this work, an innovative aluminum liquid cold plate for press-pack power applications with an internal finned geometry made with additive manufacturing is proposed and analyzed. Thermal and fluid dynamic performances are estimated by FEM simulations, which have been validated through an ad hoc test bench. Proper considerations about potential problems of the selective laser melting metal printing technique and their implications for the reliability of liquid cold plates have been done. Then, simulation results for failure conditions (short circuit and coolant liquid circuit failure cases) on a complete press-pack stack are shown. • Liquid heat sinks • Finite element modeling • Thermal modeling • High power electronics coolers • Metal additive manufacturing [ABSTRACT FROM AUTHOR]

Palynological, palaeoparasitological and paleobotanical studies of coprolites found in archaeological sites from Perito Moreno National Park (47°57′S72°05′W) yielded information on diet, palaeoenvironment and health. These studies allowed adding evidence to the reconstruction of life history of the hunter–gatherers that inhabited Patagonia during the Holocene. We examined the season of the year when camelid Lama guanicoe coprolites (5400 ± 64 yr 14C BP to 9640 ± 190 yr 14C BP) were deposited at Cerro Casa de Piedra 7 (site CCP7). The study used palynological evidence and comparison with pollen spectra of modern feces collected during summer, fall, winter and spring of 2010. The dominant types were: pollen of Nothofagus, Empetrum rubrum, Asteraceae subfam. Asteroideae, Nassauvia, Caryophyllaceae and Poaceae; fern spores; remains of Eimeria macusaniensis; and plant remains of Poaceae, Festuca pallescens, Stipa speciosa, Armeria maritima, Gaultheria mucronata and E. rubrum. Pollen spectra of modern and fossil feces were used for multivariate analysis. Coprolites associated to fall and winter modern feces. These results and those obtained from pollen concentration values and the presence of pollen types indicators of seasonality, allowed the determination of summer, fall and winter coprolites. However, caution must be taken with the seasonality results of coprolites dated earlier than 9000 years BP since the environmental conditions differed from now. The site was probably a camelid shelter during the unfavorable seasons. [ABSTRACT FROM AUTHOR]

The aim of this research was to analyze the landforms around Pueyrredón Lake (NW Santa Cruz in Argentina) to contribute to the understanding of the paleoenvironmental evolution of Patagonia during the Late Pleistocene–Early Holocene. The Pueyrredón Lake area belongs to the Patagonian shield, northwest of the Santa Cruz Province (47°22′28″ S–71°55′34″ W). Characteristic landforms were identified through satellite images (Landsat 7 ETM) and field work. These landforms include glacial troughs, glacier striations and groove casts, three fan deltas on the south margin of Pueyrredón Lake, lacustrine and glacio-lacustrine sediment, and till deposits. In addition, short detailed stratigraphic logs were measured for paleoenvironmental analysis, and several sedimentary deposits were sampled to characterize grain size variations. All of the information is displayed on a geomorphological map. The modern and ancient landforms were also analyzed based on their topographic characteristics, which were determined by a digital elevation model (DEM). Geomorphological conditions of the erosional and depositional processes in the paleoglacial environment were analyzed using longitudinal- and cross-sections. The results shed light on the climatic variability during the most recent geological period. Major changes in the landscape morphology were associated with glacier evolution and the development and division of the great lakes in the eastern Andes, in Central Patagonia. [ABSTRACT FROM AUTHOR]

Abstract: Medulloblastoma (MB) is the most common malignant brain tumor of childhood. We have investigated for novel chromosomal imbalances and prognostic markers of pediatric MB. Forty MBs out of 64, were analyzed using high resolution prometaphase comparative genomic hybridization. Chromosome 10q26.1–q26.3 loss combined with 17q24.3–q25.3 gain and/or 7q34–q36.3 gain in tumors predicted poor patient’s survival. A minimal deleted region of 14.12cM at 10q26.1–q26.3 was refined by LOH analysis. We propose a new prognostic marker for pediatric MB patient risk stratification based on the presence of 10q26.1–q26.3 loss plus 17q24.3–q25.3 gain and/or 7q34–q36.3 gain associations. [Copyright &y& Elsevier]

Objectif: Étudier la capacité de l’IRM fœtale de détecter une malrotation intestinale. Matériel et Méthodes: Étude rétrospective sur 5 ans de notre base de données d’IRM fœtales non cérébrales. Résultats: Quatre cent une IRM fœtales furent analysées. Dans 34 cas (8,5%), le jéjunum proximal était considéré en position anormale, càd ailleurs que dans le flanc gauche sous l’estomac sur les séquences pondérées en T2. Dans 22 cas (65%), le jéjunum était situé dans l’hémi-thorax gauche dans le cadre d’une hernie diaphragmatique gauche (groupe A). Dans 7 cas (20%) il était en position extra-abdominale dans le cadre d’un laparoschisis (group B). Dans 5 cas (15%) il était anormalement situé dans l’abdomen, en position médiane ou dans le flanc droit, avec un estomac en position normale (group C). Tous les cas des groupes A et B ont été confirmées en période post-natale ou à l’autopsie. Dans 4 cas du groupe C (syndrome de Prune-Belly, poche colonique, atrésie digestive, cardiopathie) la malrotation n’était pas suspectée en échographie et était confirmée après la naissance. Dans le dernier cas, l’intestin était refoulé à droite par une duplication digestive géante, et le TOGD post-natal était normal. Conclusion: Grâce à son excellente résolution en contraste en pondération T2, l’IRM fœtale identifie avec précision une position anormale du jéjunum, en dehors de toute suspicion échographique, avec une excellente corrélation postnatale. [ABSTRACT FROM AUTHOR]