Liotyphlops is a genus of blindsnakes distributed in Central and South America. We reviewed specimens of Liotyphlops albirostris along its current distribution range and, based on morphological data ...and ecological niche modeling analyses, we restrict the geographical range of L. albirostris and validate three previously described species. In this revision, we describe the morphological variation in the populations from Panamá, Colombia, Ecuador, and Venezuela, and propose a new taxonomic arrangement. We revalidate three previous synonyms of L. albirostris to full species status, while dividing the populations from Colombia in two subspecies―one attributed to a previously recognized species from the Caribbean region, and a new one from the Andean region. The new species differs from L. albirostris from Panamá in cephalic scale arrangements that effectively reduces the previously reported variability of these scales in L. albirostris. We also explore some osteological differences that are congruent with the variation observed. We hope that the recognition of these new species better represents the diversity within Liotyphlops, helping to bring these new species out of their cryptic status so that they will be considered in future conservation efforts.
Gas sensors are fundamental for continuous online monitoring of volatile organic compounds. Gas sensors based on semiconductor materials have demonstrated to be highly competitive, but are generally ...made of expensive materials and operate at high temperatures, which are drawbacks of these technologies. Herein is described a novel ethanol sensor for room temperature (25 °C) measurements based on hematite (α‑Fe
O
)/silver nanoparticles. The AgNPs were shown to increase the oxide semiconductor charge carrier density, but especially to enhance the ethanol adsorption rate boosting the selectivity and sensitivity, thus allowing quantification of ethanol vapor in 2-35 mg L
range with an excellent linear relationship. In addition, the α-Fe
O
/Ag 3.0 wt% nanocomposite is cheap, and easy to make and process, imparting high perspectives for real applications in breath analyzers and/or sensors in food and beverage industries. This work contributes to the advance of gas sensing at ambient temperature as a competitive alternative for quantification of conventional volatile organic compounds.
Urologic trauma is frequently reported in patients with penetrating trauma. Currently, the computerized tomography and vascular approach through angiography/embolization are the standard approaches ...for renal trauma. However, the management of renal or urinary tract trauma in a patient with hemodynamic instability and criteria for emergency laparotomy, is a topic of discussion. This article presents the consensus of the Trauma and Emergency Surgery Group (CTE) from Cali, for the management of penetrating renal and urinary tract trauma through damage control surgery. Intrasurgical perirenal hematoma characteristics, such as if it is expanding or actively bleeding, can be reference for deciding whether a conservative approach with subsequent radiological studies is possible. However, if there is evidence of severe kidney trauma, surgical exploration is mandatory and entails a high probability of requiring a nephrectomy. Urinary tract damage control should be conservative and deferred, because this type of trauma does not represent a risk in acute trauma management.
We announce the draft genome sequence of three Gram-negative bacteria isolated from coral tissues affected with the black band disease (BBD), identified with the NCBI's Assembly Database accession ...numbers: MBQF, MAYB and MBQE. These genome drafts constitute an useful tool for the characterisation of these bacteria and for the understanding of the relationship between the microbial consortia associated with the disease and the onset and progression of the pathology.
We report an extremely rare case of a patient with a total avulsion of the spermatic cord secondary to a blunt inguinal trauma. Doppler ultrasound was used to identify an absence of vascular flow and ...an indication for exploratory surgery. The retroperitoneum was accessed for hemostasis. Spermatic cord injury after blunt trauma is extremely rare but should be considered as a cause of an avascular testis after trauma.
Voltage-gated calcium channels are key regulators of brain function, and their dysfunction has been associated with multiple conditions and neurodegenerative diseases because they couple membrane ...depolarization to the influx of calcium—and other processes such as gene expression—in excitable cells. L-type calcium channels, one of the three major classes and probably the best characterized of the voltage-gated calcium channels, act as an essential calcium binding proteins with a significant biological relevance. It is well known that estradiol can activate rapidly brain signaling pathways and modulatory/regulatory proteins through non-genomic (or non-transcriptional) mechanisms, which lead to an increase of intracellular calcium that activate multiple kinases and signaling cascades, in the same way as L-type calcium channels responses. In this context, estrogens—L-type calcium channels signaling raises intracellular calcium levels and activates the same signaling cascades in the brain probably through estrogen receptor-independent modulatory mechanisms. In this review, we discuss the available literature on this area, which seems to suggest that estradiol exerts dual effects/modulation on these channels in a concentration-dependent manner (as a potentiator of these channels in pM concentrations and as an inhibitor in nM concentrations). Indeed, estradiol may orchestrate multiple neurotrophic responses, which open a new avenue for the development of novel estrogen-based therapies to alleviate different neuropathologies. We also highlight that it is essential to determine through computational and/or experimental approaches the interaction between estradiol and L-type calcium channels to assist these developments, which is an interesting area of research that deserves a closer look in future biomedical research.
Colorectal cancer(CRC)has a great impact on the world population.With increasing frequency,CRC is described according to the presenting phenotype,based on its molecular characteristics.Classification ...of CRC tumors according to their genetic and/or epigenetic alterations is not only important for establishing the molecular bases of the disease,but also for predicting patient outcomes and developing more individualized treatments.Early-onset CRC is a heterogeneous disease,with a strong familial component,although the disease is sporadic in an important proportion of cases.Different molecular alterations appear to contribute to the apparent heterogeneity of the early-onset population and subgroups can be distinguished with distinct histopathologic and familial characteristics.Moreover,compared with late-onset CRC,there are characteristicsthat suggest that early-onset CRC may have a different molecular basis.The purpose of this review was to analyze the current state of knowledge about earlyonset CRC with respect to clinicopathologic,familial and molecular features.Together,these features make it increasingly clear that this subset of CRC may be a separate disease,although it has much in common with late-onset CRC.
One of the most commonly used parameters to evaluate the environmental impact of petrochemical-associated industries and its consequence on human health is the presence of benzene, toluene, ...ethylbenzene, and xylene in water, which are known as BTEX. The removal of these compounds from groundwater, and thus assuring the quality of this resource, is of high relevance but challenging for regions where the technologically advanced devices required for analytical control are unavailable. Accordingly, herein, a novel silica-based nanocomposite adsorbent (MCM48/SPION/C8) was developed together with an efficient magnetic concentration/extraction and recovery method for BTEX contaminants in water samples, allowing their quantitative extraction and recovery and analysis, even in outdated systems. The implementation of magnetic nanoparticles enabled analysis by magnetic solid-phase extraction (mSPE) as expected due to the tailor-made adsorption/desorption properties associated with the easy and fast separation of the adsorbent, its recycling, and reuse. Organo-functionalization of hydrophilic and highly ordered mesoporous silica MCM48 with alkyl chains enabled hydrophobic interactions, thus tailoring its affinity for BTEX species. The novel nanocomposite adsorbent was characterized and compared with a state-of-art commercial product, demonstrating that it outperforms conventional solid-phase extraction materials in terms of recovery efficiency due to its higher specific surface area and entrapment in the hierarchical mesoporous structure achieved upon organofunctionalization with octylsilane.
(a) Cubic structures formed by CTAB above critical micellar concentration used as a template to generate highly ordered mesoporous silica. (b) Photo showing the magnetic recovery of MCM48/SPION/C8 nanocomposite in 60 s.
Para los hacedores de política fiscal es imprescindible contar con evidencia empírica expost que soporte e informe de manera exante las decisiones a tomar y las políticas a plantear en materia ...impositiva. Es por ello por lo que existen numerosos estudios empíricos que han mostrado diversos efectos de choques fiscales sobre variables macroeconómicas como el empleo, los salarios, la inversión y los ingresos. El presente artículo busca llevar a cabo un análisis concluyente sobre el efecto multivariable que tuvo una reglamentación tributaria colombiana sobre el subsector económico de restaurantes catering y bares, a partir del cambio del impuesto al valor agregado IVA (16%), que permite deducir el impuesto pagado por consumo intermedio, por el impuesto al consumo (8%) que, aunque tiene una menor tasa, no permite esta deducción. Se estimó el impuesto potencial pagado con ambos tributos, buscando conocer si la reglamentación significó una reducción en la carga y, posteriormente, haciendo uso de un modelo de regresión discontinua que compara este subsector en cuestión con otros subsectores similares presentes en la encuesta anual de servicios del DANE, se encontró un efecto positivo de esta reglamentación sobre las variables de interés, por ejemplo, significó un incremento de 23% en la producción nominal promedio de las empresas del sector al compararse con otros sectores que no fueron cobijados por esta reforma.
For fiscal policy makers, it is essential to have empirical evidence to support and inform ex ante the decisions to be made and the policies to be proposed in tax matters. That is why there are numerous empirical studies that have shown various effects of fiscal shocks on macroeconomic variables such as employment, wages, investment, and income. This article develops a conclusive analysis of the multivariate effect that a Colombian tax regulation had on the economic subsector of restaurants, catering and bars, starting with the change in the value added tax VAT (16%), which allows the deduction of the tax paid for intermediate consumption, for the consumption tax (8%) which, although has a lower rate, does not allow this deduction. The potential tax paid with both taxes was estimated, seeking to know if the regulation meant a reduction in the burden and, subsequently, making use of a discontinuous regression model that compares this subsector in question with other similar subsectors present in DANE’s annual services survey, a positive effect of this regulation on the variables of interest was found. For example, this tax change meant an increase of 23% in the average nominal production of the companies in the sector when compared with other sectors that were not covered by this reform.
Background. The selection of indicators and their use for the evaluation of agricultural sustainability at the watershed level is addressed. Objective. To discuss the importance of their use and the ...options of existing methodological frameworks for this purpose. Main findings. the concept of indicator and its characteristics are defined; subsequently, the main methodological frameworks used in the selection of indicators are described, with emphasis on the assessment of agricultural sustainability in watersheds. Conclusions. In the evaluation of agricultural sustainability at the watershed level, it is highlighted the selection of indicators based on a methodological framework that integrates the three dimensions of sustainability (social, ecological and economic). It was considered the management and interactions of the agroecosystems with other external systems and internal subsystems within the watershed. It is emphasized the importance of selecting indicators in a participatory manner, with producers and the application of multivariate analysis that may contribute to the generation of sustainability indices
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