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BACKGROUND: Pretibial injury is common. Although the mechanism of injury may be minor, in a specific patient population, misdiagnosis and delay in appropriate treatment can lead to dire consequences. The ability to identify and properly treat these patients early has the potential to reduce the need for surgical intervention, hospitalization, and prolonged care. METHODS: A literature review was performed to develop the Lower Extremity Hematoma Algorithm (LEHA) to aid in identifying and managing these injuries in the patient population at greatest risk. RESULTS: A case example is provided to demonstrate how implementation of the LEHA may have led to early diagnosis and treatment, avoiding expensive advanced and prolonged care.CONCLUSION: Implementation of the LEHA may expedite the identification of patients at risk for deep dissecting hematomas, enabling faster implementation of appropriate treatment and thereby helping to contain health care costs through avoiding surgical intervention.

Trends in crystalline silicon photovoltaic improvements demonstrate that some of the key factors that have contributed to reaching efficiency values up to 23 % are the introduction of the passivated emitter and rear cell structure with local rear contacts in low-cost large-volume fabrication; the reduction of the width of the front metallization fingers, from about 100 microm to less than 30 micro m in large volume production, and the re-emergence of mono-crystalline silicon wafers as a consequence of cost reduction in the Czochralski silicon ingot fabrication process. In the present work, we have developed a theoretical model that defines the geometric arrangement of a branched top metallic contacts network over a solar cell with a disc-shaped body. The solar cell considers two main regions: the solar cell material and an insert of metallic material for the collection of the photogenerated electrical current. The geometric characteristics of the network are defined from the minimization of the resistive power losses applying the constructal design method. As a fundamental result, the optimal lengths, branching angles, and geometrical relationships of the n-branched network are determined. The numerical results show that the dimensionless power losses of the branched arrangement of contacts present minimum values for the allocation of the metallic material and the disc size of the solar cell.

Actively caring for the environment is an issue that prevails in the international debate, and our country takes part on this argument. One aspect of environmental deterioration is, with no doubt, atmospheric pollution; a constant in modern societies, which, in the attempt to find growth and development, impact the natural and urban environment they inhabit. A distinctive feature of commercial and economic exchange are the strategic cities, so-called capitals, in addition to the territories where coastal tourism predominates as an engine of regional human development. In this balance, which is far from being sustainable and fair, an exponential consumer market dominates and generates the progressive increase in the use of fossil fuels. The former being emitted into the atmosphere, in such a way that they alter chemical composition and cause harmful air quality. In addition, the territory is impacted, intoxicating the soil and water, which are the final deposit. The objective of this work is to determine the temporal behavior of atmospheric pollutants in the city of Tepic, Nayarit, Mexico and to identify the dominant pollution indicators considering the international and national context. Through the statistical analysis of the databases of particles smaller than 2.5 micrometers, particles smaller than 10 micrometers and carbon monoxide, the behaviors of these pollutants in the study area were obtained. Among the most significant results, particles smaller than 2.5 micrometers showed maximum levels outside the norm almost all year round, with values ​​reaching 170 micrograms per cubic meter. On the other hand, the particles smaller than 10 micrometers presented satisfactory levels in their average behavior; however, the maximum concentrations remained outside the official Mexican standard. Regarding the analysis of CO, a behavior within the maximum permissible limits of protection for the population was reported; Nevertheless, by favoring the formation of tropospheric ozone, its contribution is significant, especially when the atmosphere is highly photo-reactive. This research can be used as a timely tool for mitigation of climate change, where the results contribute to the review and rethinking of public management of the environment towards sustainable development.

We have developed a network of pipes of dendritic geometry in a solar collector with a disc-shaped body.The fluid in the network pipes is a nanofluid composed of a mixture of nanoparticles of alumina (Al2O3)and water as a base fluid in order to harvest a greater amount of thermal energy from incoming solarradiation. The sizes of the network pipes are obtained by using constructal theory methods. Thermal con-ductivity was obtained by the Hamilton-Crosser model; physical properties such as density and specificheat capacity were described as a function of the volumetric fraction of nanoparticles in the fluid. Optimalsize of the network presented for every level of construction was established by the condition of minimalthermal resistance. Temperature profiles and the aspect ratio of the construction elements were definedas a function of the volumetric fraction of nanoparticles. Results show that by increasing the volume frac-tion of nanoparticles, thermal energy gain also increases, reaching a higher outlet temperature of the fluidwhen alumina nanoparticles are used.

As-deposited bismuth sulfide thin films prepared by means of a chemical bath deposition were treated with argon AC plasma. In this paper, we present the results on the physical modifications which were observed when a pre-treatment, containing a solution of 1 M sodium hydroxide, was applied to the glass substrates before depositing the bismuth sulfide. The bismuth sulfide thin films were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, atomic force microscopy, UV-VIS, and electrical measurements. The XRD analysis demonstrated an enhancement in the crystalline properties, as well as an increment in the crystal size. The energy band gap value was calculated as 1.60 eV. Changes in photoconductivity (σp) values were also observed due to the pre-treatment in NaOH. A value of σp = 6.2x10−6 (Ω-cm)−1 was found for samples grown on substrates without pre-treatment, and a value of σp = 0.28 (Ω-cm)−1 for samples grown on substrates with pre-treatment. Such σp values are optimal for the improvement of solar cells based on Bi2S3 thin films as absorber material.

CuInS 2 thin films were formed by the sequential deposition of In 2 S 3 –CuS layers on glass substrates, by chemical bath deposition technique, and heating these multilayer 1 h at 350 °C and 400 mPa. The morphology and thickness of the CuInS 2 thin films were analysed by scanning electron microscopy, showing particles with elongated shape and length about 40 nm, and thickness of 267 and 348 nm for samples from 15 and 24 h of deposition time in the chemical bath of In 2 S 3 , respectively. The energy band gap values of the films were around 1.4 eV, whereas the electrical conductivity showed values from 64.91 to 4.11 × 10 − 3 Ω − 1 cm − 1 for the samples of 15 and 24 h of In 2 S 3 deposition bath, respectively. The obtained CuInS 2 films showed appropriate values for their application as an absorbing layer in photovoltaic structures of the type: glass/SnO 2 :F/CdS/Sb 2 S 3 /CuInS 2 /PbS/C/Ag. The whole structure was obtained through chemical bath deposition technique. The solar cell corresponding to 15 h of In 2 S 3 deposition duration bath showed energy-conversion efficiency ( η ) of 0.53% with open circuit voltage ( V oc ) of 530 mV, short circuit current density ( J sc ) of 2.43 mA cm − 2 , and fill factor ( FF ) of 0.41. In the case of the structure with 24 h of deposition of In 2 S 3 bath, η = 0.43% was measured with the following parameters: V oc = 330 mV, J sc = 4.78 mA cm − 2 and FF = 0.27.

As-deposited bismuth sulfide (Bi 2 S 3 ) thin films prepared by chemical bath deposition technique were treated with thermal annealed in air atmosphere and argon AC plasma. The as-deposited, thermally annealing and plasma treatment Bi 2 S 3 thin films have been characterized by X-ray diffraction (XRD) analysis, atomic force microscopy analysis (AFM), transmission, specular reflectance and electrical measurements. The structural, morphological, optical and electrical properties of the films are compared. The XRD analysis showed that both post-deposition treatments, transform the thin films from amorphous to a crystalline phase. The atomic force microscopy (AFM) measurement showed a reduction of roughness for the films treated in plasma. The energy band gap value of the as-prepared film was E g = 1.61 eV, while for the film thermally annealed was E g = 1.60 eV and E g = 1.56 eV for film treated with Plasma. The electrical conductivity under illumination of the as-prepared films was 3.6 × 10 −5 (Ω cm) −1 , whereas the conductivity value for the thermally annealed films was 2.0 × 10 −3 (Ω cm) −1 and for the plasma treated films the electrical conductivity increases up to 7.7 × 10 −2 (Ω cm) −1 .

Grid-connected photovoltaic (PV) systems are needed to introduce photovoltaic energy into rural and urban areas in México. Two 2.4 kWp grid-connected PV systems have been installed for the present study. Each system consists of 10 modules of 240 Wp rated at 15.0% efficiency under standard conditions, covering a roof area of 16.45 sq. m. approximately. One system has been installed at the University of Nayarit in Tepic (21°29’N, 104°53’W, 920 m above msl) in the Pacific coastal area oriented toward the south inclined at 22° to the horizontal and with an azimuth of 9° to the southwest (building orientation). Its main purpose is to introduce the society to the use of renewable energy and the benefits that it represents towards sustainability. The installation also helps the faculty in teaching students topics related to the scientific and technological aspects of the photovoltaic solar energy conversion. The other system has been installed on a suburban house in Temixco-Morelos (18°51’N, 99°13’W, 1450 m above msl) in a hilly inland area with an inclination angle of 15° to the horizontal, and oriented 30o from the south toward west (azimuth angle) due to architectural limitation. The purpose was to meet the total electrical energy need for a middle-class family and hence promote massive use of this type of system in this region of the country. Both systems are grid-tied through a 3kW inverter. The supplied grid energy and performance ratio of the same type PV system in two different climatic locations are described in this work. During a twelve month period, of July-2012 to June 2013, the Tepic-installation generated 3888 kWh, whereas the Temixco-installation generated 4118 kWh. Monthly average daytime temperature and meteorological parameters for this period in Tepic-Nayarit and Temixco-Morelos, are also presented. The Temixco-Morelos PV system supplied nearly 90% of electrical energy need for the house. Results establish that grid-connected PV system is feasible over vast areas in Mexico.

En este trabajo presentamos un método simple para formar una superficie catalítica que promueva la nucleación y crecimiento de películas delgadas de sulfuro de bismuto depositadas por la técnica de baño químico sobre sustratos de vidrio coming. El método consiste en el pretratamiento de los sustratos mediante inmersión en diferentes soluciones que contienen sodio: i) hidróxido de sodio, ii) citrato de sodio y iii) tiosulfato de sodio. Se analizaron las propiedades estructurales, ópticas y eléctricas de las películas obtenidas en función de la fuente de sodio utilizada. Los resultados experimentales demuestran que las propiedades físicas de las películas así como la adhesión al sustrato mejoran con respecto a aquellas obtenidas sin el pre-tratamiento

CdS/Sb2S3/PbS structures were prepared by sequential chemical deposition of CdS, Sb2S3 and PbS thin films on TEC-8 (Pilkington) transparent electrically conductive SnO2 (TCO) coatings. CdS thin films (100 nm) were deposited with hexagonal structure from Cd-citrate bath and of cubic structure from Cd-ammine/triethanolamine bath. Sb2S3 thin films were deposited at 40 °C from a solution mixture of potassium antimony tartrate, triethanolamine, ammonia and thioacetamide(TA) or at 1 to 10 °C from a mixture of antimony trichloride and thiosulfate (TS). These films were made photoconductive by heating at temperatures 250 to 300 °C. When heated in the presence of a chemically deposited Se thin film of 300 nm, a solid solution Sb2S1.8Se1.2 resulted. PbS thin films of 100–200 nm thickness were deposited on the TCO/CdS/Sb2S3 or TCO/CdS/Sb2S1.8Se1.2 structure. Graphite paint was applied on the PbS film prior to applying a silver epoxy paint. The cell structures were of area 0.4 cm2. The best results reported here is for a cell: TCO/CdS(hex-100 nm)/Sb2S3(TS-100 nm)/PbS(200 nm) with open circuit voltage (Voc) 640 mV, short circuit current density 3.73 mA/cm2, fill factor 0.29, and conversion efficiency 0.7% under 1000 Wm− 2 sunlight. Four series-connected cells of area 1 cm2 each gave Voc of 2 V and short circuit current of 1.15 mA.

Antimony sulfide thin films of thickness ≈ 500 nm have been deposited on glass slides from chemical baths constituted with SbCl3 and sodium thiosulfate. Smooth specularly reflective thin films are obtained at deposition temperatures from − 3 to 10 °C. The differences in the film thickness and improvement in the crystallinity and photoconductivity upon annealing the film in nitrogen are presented. These films can be partially converted into a solid solution of the type Sb2SxSe3 − x, detected in X-ray diffraction, through heating them in contact with a chemically deposited selenium thin film. This would decrease the optical band gap of the film from ≈ 1.7 eV (Sb2S3) to ≈ 1.3 eV for the films heated at 300 °C. Similarly, heating at 300 °C of sequentially deposited thin film layers of Sb2S3–Ag2Se, the latter also from a chemical bath at 10 °C results in the formation of AgSb(S/Se)2 with an optical gap of ≈ 1.2 eV. All these thin films have been integrated into photovoltaic structures using a CdS window layer deposited on 3 mm glass sheets with a SnO2:F coating (TEC-15, Pilkington). Characteristics obtained in these cells under an illumination of 850 W/m2 (tungsten halogen) are as follows: SnO2:F–CdS–Sb2S3–Ag(paint) with open circuit voltage (Voc) 470 mV and short circuit current density (Jsc) 0.02 mA/cm2; SnO2:F–CdS–Sb2S3–CuS–Ag(paint), Voc ≈ 460 mV and Jsc ≈ 0.4 mA/cm2; SnO2:F–CdS–Sb2SxSe3 − x–Ag(paint), Voc ≈ 670 mV and Jsc ≈ 0.05 mA/cm2; SnO2:F–CdS–Sb2S3–AgSb(S/Se)2–Ag(paint), Voc ≈ 450 mV and Jsc ≈ 1.4 mA/cm2. We consider that the materials and the deposition techniques reported here are promising toward developing ‘all-chemically deposited solar cell technologies.’

En México, los residuos sólidos urbanos son una problemática de contaminación ambiental y un tema que requiere sertratado desde la transversalidad. El estilo de vida actual, basado en una dinámica de consumo, conlleva al uso masivo dediversas tecnologías; entre ellas, los equipos electrónicos. Una vez que éstos terminan su vida útil, se convierten enresiduos, llamados e-waste, que, en la mayoría de los casos, son dispuestos en vertederos a cielo abierto, sin programas demanejo especial. Estos residuos se componen de metales y diversas sustancias nocivas a la salud, emitiendo gases tóxicos que generan problemas ambientales y de salud pública. La presente investigación tiene como objetivo mostrar losresultados del Programa de Separación Selectiva de la Universidad Autónoma de Nayarit (UAN), que para el casoespecífico de los residuos electrónicos se denominó "Reciclatrón". La reparación de residuos y su clasificación serealizaron de acuerdo a la Norma Oficial Mexicana NOM-161-SEMARNAT-201 l. Para la ejecución del programa seutilizaron metodologías participativas para formar equipos los equipos de traba jo. El acopio de residuos ha tenido unatendencia creciente durante las tres ediciones en que se ha realizado y se estima, de acuerdo a la tendencia de losresultados, que de no realizar acciones orientadas a la reducción del consumo el crecimiento será exponencial. Elprograma ha servido al mismo tiempo como una oportunidad de fomento a la cultura de la prevención, el conocimiento yla concientización del problema ambiental que se originan los residuos electrónicos dentro y fuera de la comunidadUniversitaria, cuando no son manejados adecuadamente, lo cual se discute también en el presente trabajo.

Antimony sulfide thin films (300 nm) have been deposited on glass substrates at 1–10°C from chemical bath. When heated these become crystalline and photoconductive with optical band gap (direct) of 1.7 eV. Thin films formed from chemical baths containing SbCl3 and sodium selenosulfate are of mixed phase Sb2O3/Sb2Se3, which when heated in the presence of Se-vapor converts to single phase Sb2Se3 film with optical band gap of 1.1 eV. Such films possess dark conductivity of 10-8 ohm-1cm-1 and show photosensitivity of two orders. Reaction of Sb2S3-CuS in nitrogen at 400°C produces crystalline, photoconductive p-type CuSbS2 with optical band gap (direct) of 1.5 eV. By controlling the deposition and heating condition, (i)Sb2S3-(p)CuSbS2 layer is formed, which is utilized in a photovoltaic structure, (n)CdS:In-(i)Sb2S3-(p)CuSbS2, with a Voc of 345 mV and Jsc 0.18 mA/cm2 under 1 kW m-2 tungsten halogen illumination. In the case of a structure, CdS:Cl-Sb2S3-Cu2-xSe, Voc of 350 mV and Jsc of 0.5 mA/cm2 are observed.

Although ethanol can be produced from a wide range of biomass materials, biomass, from the tropical region, like mango (skin or bagasse) is a crop residue readily available today as a non-conventional crop for the saccharification process that has had little attention. It has the benefits to be found in large quantities and in an industrial level is completely separated into its components with a free access for acid or enzymatic hydrolysis. These agro-industrial waste as well as other materials like sugarcane bagasse and pine wood are abundant enough, and in virtue of their high carbohydrate content hold tremendous potential for large-scale bioethanol production. The objective of this work is to develop a comparative analysis using dilute acid hydrolysis process between mango (skin and bagasse), sugarcane bagasse, and pine wood. The biomass was subjected to pretreatments like alkaline hydrolysis using calcium sulfate and sodium hydroxide, water immersion, and water autoclaved at 121 °C. Experimental results showed that the maximum percentages of sugar recovery were for sugarcane bagasse—56.62%, pine wood—82.36%, mango skin—97.37%, and mango bagasse—202.91%. From the tested biomass materials, only mango bagasse has a considerable fraction of already digestible sugar that does not undergo a pretreatment + hydrolysis process.

Ni-W catalysts supported on CeO2,Al2O3 and hydrotalcite (HT) were studied in the steam reforming of ethanol at 500-650ºC. The CeO2 and HT were synthesized by impregnation and direct coprecipitation methods, respectively. Commercial Al2O3 was used. Nickel content was varied from 10, 15 and 30% with 1% W. The catalyst that presented the highest catalytic activity and selectivity to hydrogen was 10% Ni-W/HT. Conversion to ethanol was 100% and selectivities to H2, CH4, CO2 and CO were 75, 5.78, 0.37 and 18.85%, respectively, at a temperature of 500 ºC. Moreover, these catalysts showed good stability with respect to carbon deposition and low selectivity towards C2H4 production. These are desirable features for catalysts to be used in hydrogen production for fuel cell applications.

Chemically deposited antimony selenide (Sb 2 Se 3 ) thin film has a coexisting antimony oxide (Sb 2 O 3 ) phase which may be converted to crystalline Sb 2 Se 3 thin films with an optical bandgap of 1.13 eV when heated at 300°C in nitrogen in the presence of selenium vapor. Instead of this, if the heating is done with an Sb 2 S 3 thin film on the chemically deposited Sb 2 Se 3 :Sb 2 O 3 thin film, a solid solution with the coexisting oxide phase (Sb 2 Se 3-x S x :Sb 2 O 3 ) is produced. The optical bandgap of such absorber material is 1.34-1.58 eV. The as-deposited thin films as well as those produced by heating are photoconductive. They were incorporated into solar-cell structures developed entirely by chemical deposition on SnO 2 :F-coated commercial transparent conductive oxide (TCO) glass. The cell structure, TCO/CdS/Sb2Se3:Sb203/PbS, showed an open-circuit voltage (V oc ) of 540 mV and short-circuit current density (J sc ) of 0.67 mA/cm 2 . In the cell TCO/CdS/Sb2Se 3-x S x :Sb 2 O 3 /PbS produced by heating in nitrogen, V oc is 520 mV, J sc is 4.2 mA/cm 2 , and conversion efficiency (η) is 0.66%. The scalability of the all-chemically deposited solar cell is demonstrated in four series-connected cells of area 1 cm 2 each, showing short-circuit current of 1.5 mA and V oc of 1.9 V under sunlight.

Antimony sulfide thin films (thickness, 500 nm) were deposited on chemically deposited CdS thin films (100 nm) obtained on 3 mm glass substrates coated with a transparent conductive coating of SnO2:F (TEC-15 with 15 Ω sheet resistance). Two different chemical formulations were used for depositing antimony sulfide films. These contained (i) antimony trichloride dissolved in acetone and sodium thiosulfate, and (ii) potassium antimony tartrate, triethanolamine, ammonia, thioacetamide and small concentrations of silicotungstic acid. The films were heated at 250 °C in nitrogen. The cell structure was completed by depositing a 200 nm p-type PbS thin film. Graphite paint applied on the PbS thin film and a subsequent layer of silver paint served as the p-side contact. The cell structure: SnO2:F/CdS/Sb2S3 (i or ii)/PbS showed open circuit voltage (Voc) of 640 mV and short circuit current density (Jsc) above 1 mA cm−2 under 1 kW m−2 tungsten–halogen radiation. Four cells, each of 1.7 cm2 area, were series-connected to give Voc of 1.6 V and a short circuit current of 4.1 mA under sunlight (1060 W m−2).

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Solar cell structures with Sb2SxSe3-x and PbS as absorber layers were fabricated by chemical deposition on commercial transparent conductive oxide coated glass. The solid solution here was prepared by heating at 250°C a Sb2S3 thin film in contact with a chemically deposited Se-thin film. It has a graded band gap of 1-1.8 eV. A PbS thin film deposited on this layer basically fulfils the role of a p+ layer; its role as an absorber is yet to be studied. Open circuit voltage of 560 mV and short circuit current density ¡Ö 1mA/cm2under 1-3 kW/m2 tungsten halogen radiation are characteristics of these cells. Optimization of the film thicknesses and heating may offer prospects for these materials toward alternate thin film solar cell technology.