bluuebunny/crossref_metadata_2025 huggingface dataset:
A VALIDATED STABILITY INDICATING ULTRA-PERFORMANCE LIQUID CHROMATOGRAPHIC METHOD FOR SIMULTANEOUS DETERMINATION OF METFORMIN HYDROCHLORIDE AND EMPAGLIFLOZIN IN BULK DRUG AND TABLET DOSAGE FORM
Authors: Gopal N. Madana , Sridhar C.
Published: May 2017

Objective: To develop a simple, precise, accurate, method was developed and validated for analysis of metformin hydrochloride (MET) and empagliflozin in (EMPA) in bulk and tablet dosage form.Methods: The method used a reverse phase column, dikma C18 (50×2.1 mm, 1.8 μ), a mobile phase comprising of phosphate buffer (pH-3): methanol (30:70 v/v) flow rate of 1.0 ml/min and a detection wavelength of 240 nm using a photodiode array detector. The proposed method was validated for various parameters like linearity, precision, accuracy, robustness, ruggedness, detection, quantification limits, stability studies, formulation analysis as per International Conference on Harmonization (ICH) guidelines.Results: The retention time was found to be 1.189 min and 1.712 min for MET and EMPA respectively. The proposed method was found to be having linearity in the concentration range of 500-2500 μg/ml for MET (r2=0.989) and 5-25 μg/ml for EMPA (r2=0.994), respectively. The mean % recoveries obtained were found to be 100.35-100.48% for MET and 99.80-101.30% for EMPA respectively. Stress testing which covered acid, base, peroxide, photolytic and thermal degradation was performed on under test to prove the specificity of the method and the degradation was achieved. The developed method has been statistically validated according to International Conference on Harmonization (ICH) guidelines.Conclusion: Thus, the proposed method can be successfully applied for the stability indicating the simultaneous determination of MET and EMPA in bulk and combined tablet dosage form and in the routine quality control analysis.
UV-VISIBLE SPECTROSCOPIC AND FTIR ANALYSIS OF SARCOSTEMMA BREVISTIGMA, WIGHT. AND ARN
Authors: Dhivya S. M. , Kalaichelvi K.
Published: May 2017

Objective:  The present study was carried out to characterize the bioactive constituents present in aerial parts of ethanolic extract of Sarcostemma brevistigma using UV-VIS and FTIR.Methods:  FTIR spectroscopy is an established time‐saving method to characterize and identify functional groups.Results:  The UV-VIS profile showed different peaks ranging from 200‐1044 nm with different absorption respectively. UV-VIS profile showed the peaks at 254.00 and 680.00 nm for flavonoid. FTIR spectra showed the peak at 3418.85 cm-1 for N-H group. FTIR analysis and UV-VIS analysis showed the presence of flavonoids and a phenolic compound. The FTIR spectra had amply evidenced the occurrence of OH group together with the Terpenoids, and Phenol. The FT-IR spectrum showed the presence of an amine (N-H), alkyl (C-H), nitrile (C≡N), halo formyl (C=O), alkenyl (C=C), hydroxyl (O-H), haloalkane (C-F), nitrates and carbonate compounds.Conclusion:  The results confirm the fact that this plant posse’s important bioactive constituent, so further scientific investigation is needed.
A PILOT INVESTIGATION INTO ASSOCIATIONS BETWEEN VARIOUS INDOOR AIRBORNE FUNGAL PARTICLES IN TRIPLICANE PUBLIC TOILET OF CHENNAI, TAMIL NADU
Authors: Anjum Km. Rubab , Sivakumari K. , Ashok K. , Rajesh S.
Published: May 2017

Objective: To study and to explore the fungal species present in indoor toilet environment.Methods: Lactophenol cotton blue staining.Results: 5 fungi isolates belonging to 5 genus were identified namely Aspergillus niger, Aspergillus fumigates, Aspergillus flavus, Aspergillus terreus and Rhizopus oryzae.Conclusion: In order to improve the quality of indoor toilet environment regular cleaning and disinfection should be done daily.
FORMULATION AND BIO-AVAILABILITY PARAMETERS OF PHARMACEUTICAL SUSPENSION
Authors: Doye Pakpi , Mena Tanya , Das Nilimanka
Published: May 2017

The suspension is a biphasic liquid or semi-solid dosage form where the finely divided insoluble solid drug particles are homogeneously dispersed in a liquid or semi-solid medium. The solid drug particles act here as the dispersed phase and the liquid or the semi-solid as the dispersion medium. Suspensions contribute to pharmaceutical dosage form development by supplying drugs that are insoluble in all acceptable medium and often distasteful. Suspension translates such drugs into more bio-available form when compared to capsules, tablets, coated tablets, enteric coated tablets and sustained release products. The dosage form is palatable to the patient and many are doing well when applied to the skin or mucous membrane. This particular dosage form is also applied for injecting drugs into the systemic circulation. Therefore, pharmaceutical suspension finds its application through three different routes of administration namely oral, externally applied suspension and injectable one. The success of any dosage form largely depends on formulation parameters and the factors that influence the bioavailability which ultimately dictate the therapeutic success of the formulated dosage form. Hence, it is obvious to discuss the formulation parameters and the factors influencing bioavailability of suspension for the therapeutic success of it.
COMPARISON OF THREE HERBAL PLANTS FOR BEST FREE RADICAL SCAVENGING ACTIVITY
Authors: Palaniswamy Radha , Padma Palghat Raghunathan
Published: May 2017

Objective: Excessive production of reactive oxygen species leads to oxidative stress. Antioxidants can prevent or retard the oxidation caused by free radicals and sufficient intake of antioxidants is supposed to protect against diseases. Candidate play  Methods: The leaf extracts of these plants were exposed to a battery of free radical scavenging assays like DPPH, ABTS, hydrogen peroxide, superoxide and nitric oxide to determine the free radical scavenging activity.Results: It was observed that the Majoranahortensis leaves in methanolic extract showed maximum scavenging activity.Conclusion: Several plants with free radical scavenging activity have been identified, where Majoranahortensis is one such leave.
TOTAL FLAVONOID QUANTIFICATION AND TO STUDY ANTIBACTERIAL POTENCY OF EXTRACTS OF BUTEA MONOSPERMA FLOWERS, NIGELLA SATIVA SEEDS AND VITEX AGNUS CASTUS LEAVES
Authors: Jain Kajal L. , Choudhury P. K. , Sharma Maya
Published: May 2017

Objective: An attempt has been made to develop a method for quantitative estimation of flavonoids in the crude extract of Butea monosperma flowers, Nigella sativa seeds and Vitex agnus castus leaves. Antibacterial activity is attributed to various phytochemicals present in these plants.Methods: The amount of total flavonoids was analysed using aluminium chloride colorimetric assay using rutin as standard. Plants studied were subjected to hydromethanolic extraction by using soxhlet apparatus. Flavonoids in extracts were quantified by U. V at a wavelength of 415 nm Antibacterial activities of extracts were evaluated on various bacterias like E. coli, P. aeruginosa, S. aureus, S. pneumonie, P. acne. The in vitro antibacterial activities of these extracts were compared against standard drugs such as gentamycin, ampicillin, chloramphenicol, ciprofloxacin, norfloxacin.Results: Flavonoid content in the crude extract of Butea monosperma flowers, Nigella sativa seeds and Vitex agnus castus leaves was found to be 2.58 %w/w, 0.92% w/w and 1.6 % w/w respectively. The antibacterial study found that activity of Vitex extract against P. acne was better than the standard drugsConclusion: In the present study an attempt has been made to standardize the plant material in terms of its flavonoid content and the study indicated that this extract individually or in combination with other herbal drugs can be useful in treating diseases caused by the organisms mentioned above.
REVIEW ARTICLE: SOLUBILITY ENHANCEMENT BY SOLID DISPERSION
Authors: Patil A. N. , Shinkar D. M. , Saudagar R. B.
Published: May 2017

Enhancement of solubility, dissolution rate and bioavailability of the drug is a very challenging task in drug development, nearly 40% of the new chemical entities currently being discovered are poorly water soluble drugs. The solubility behaviour of the drugs remains one of the most challenging aspects in formulation development. This results in important products not reaching the market or not achieving their full potential. Solid dispersion is one of the techniques adopted for the formulation of such drugs and various methods are used for the preparation of solid dispersion. Solid dispersion is generally prepared with a drug which is having poor aqueous solubility and hydrophilic carrier. This article review various methods and concept of solid dispersion, criteria for drug selection, advantage and disadvantage, characterization, and application.
ANTIMICROBIAL ACTIVITY OF SOME FOLK MEDICINAL PLANTS USED IN RAJASTHAN AGAINST SELECTED PATHOGENIC MICROORGANISMS
Authors: Verma Maya , Kumar Ashwani
Published: May 2017

Objective: To investigate the antibacterial efficacy of methanol extracts of leaves and roots of B. diffusa, Eclipta alba, Phyllanthus niruri and Ricinus communis.Methods: The antimicrobial efficacy of methanol extracts of some medicinal plants was evaluated by agar well diffusion method against selected pathogenic bacterial strains. Gram+ve strains (S. aureus, B. subtilis) were tested and Gram-ve strains tested were (E. coli, S. typhii and K. pneumoniae). Antifungal activity against was tested.Results: B. diffusa and P. niruri leaf extract showed highest antibacterial activity against S. aureus and S. typhii. Leaf extract of P. niruri and R. communis showed highest antifungal activity against A. niger and C. albicans respectivelyConclusion: The methanolic leaf extracts of B. diffusa and P. niruri were highly active against S. aureus and S. typhii.
Personality, Attitude and Behavioural Components of Financial Literacy: A Comparative Analysis
Authors: Németh Erzsébet , Zsótér Boglárka
Published: May 2017

Since the financial crisis in 2008 the investigation of financial literacy–especially its components (personality, attitudes, behaviour etc.) - is in the limelight. Modern economics have recognized that in order to effectively forecast financial and economic processes it is primordial to understand the attitudes of the members of society toward finances, as well as the characteristics of various social group sharing the same views and behaviours. In 2015 two relevant pieces of research were conducted in this topic in Hungary. One focuses on the financial personality types, while the other investigates Hungarians’ financial culture in general based on the research methodology of the OECD. Based on these two databases our comparative study highlights the main characteristics of financial personality types. The three clusters based on the OECD research cover the nine personality types from the results of the other Hungarian research. Our findings show that the cluster of “anxious unsatisfied” encapsulates the “economizers with little money”, the “price sensitive” and the “collector” personality types. Furthermore, the “satisfied conscious” covers the “order creates value”, the “diligent” and the “planner” personality types. Finally, the “moderately anxious unconsidered” involves the “ups and downs”, the “money-devouring” and the “cannot control finances” personality types. The clusters identified during the research show idiosyncratic financial and psychological vulnerability and/or protection.
Customer Perceptions of Skills of Agents in Effectively Managing Their Needs within a Call Center
Authors: Oodith Devina
Published: May 2017

The world’s dynamics and demands of employment and production have evolved over the past decade. Human resources has today become the single largest unrestrained resource and many firms are striving to enhance competence and interaction between its customers and itself via the customer call center through enhanced skills, knowledge, ability and attitude by fostering better interpersonal skills and through the promotion of training and development of their call center agents. This study was undertaken in EThekwini (Durban), South Africa and was conducted within a Public Sector service environment comprising of four major call centers employing a total of 240 call center agents. Using simple random sampling, 220 customers were drawn from all consumers subscribing to e-billing in EThekwini (Durban). Data for the customer sample was collected using a precoded, self-developed questionnaire whose psychometric properties were statistically determined. Data was analyzed using descriptive and inferential statistics. The results specify that agents were unsuccessful in handling customers’ needs timeously and efficiently and that most customers felt burdened by being transferred to other agents due to the incompetence of original agents in handling their queries/complaints. Furthermore it was found that there was an overall lack of empathy from agents in following-up after a customer communication to ensure that the customer was satisfied with their experience within the call center. Based on the results of the study recommendations have been made to manage the interaction between the customers and call center agents more competently and efficiently.
Academics’ Perceptions of the Principles for Responsible Management Education (PRME) for Sustainable Development
Authors: Boodhoo Suvera , Parumasur Sanjana Brijball
Published: May 2017

In light of business leaders’ failings, including corporate corruption, the financial crisis and various ecological system crises there is a growing expectation that management education institutions should be leading thought and action on issues related to corporate responsibility and sustainability. Therefore, there is a need to ascertain management education institutions’ ability to ensure responsible and sustainable management education. This paper seeks to assess academics’ perceptions of how the University of KwaZulu-Natal has adopted the United Nation (UN) supported initiative, Principles for Responsible Management Education (PRME), to ensure responsible and sustainable management education in South Africa. The sample was drawn using the probability sampling technique called cluster sampling. Permanent academic staff from the Graduate School of Business and Leadership and the School of Management, Information Technology and Governance who responded to the structured, self-administered questionnaire formed the sample. Questions asked related to fostering a sustainable culture, strategically adapting curriculum, creating learning environments, aligning research, fostering sustainable partnerships and encouraging constant dialogue with regards to PRME. In order to assess the implementation of the PRME for sustainable development, a quantitative research design was adopted. This is the first study, to the researcher’s knowledge, to examine the University of KwaZulu-Natal’s Graduate School of Business and Leadership and the School of Management, Information Technology and Governance’s motives, effects and challenges of engaging in PRME. The study has also explored key aspects such as the adaptation of teaching practices by the academic staff, the role of academics and diversification that influences the decision of the Graduate School of Business and Leadership and School of Management, Information Technology and Governance to participate in PRME. The results indicate that academic staff in both schools is engaging in activities that pursue the cause of sustainable development. There is evidence of addressing modern societal and environmental challenges by fostering change in design in curricula, fostering a sustainable culture and creating a learning environment. However, evidently more careful and deliberate attention needs to be given to fostering constant dialogue and aligning PRME and research to enhance economic, environmental and social development. This study provides a model/framework to present current practices and obstacles/setbacks experienced in adopting PRME and will present recommendations to facilitate the adoption of PRME by UKZN.
Regulation, Cross Border Migrants and the Choice of Remittance Channels in South Africa
Authors: Akinboade Oludele Akinloye , Daseman Anrich , Taft Trevor , Molobi Victor M.S.
Published: May 2017

Remittances have become an increasingly important factor in developing economies. Among others, compliance with onerous regulation requirements discourages the use of formal methods of remittances. The paper discusses results from a survey of the influence of regulation on the choice of migrants’ remittance channels in South Africa. It aims to highlight how regulation affects the choice between formal and informal channels of remitting funds. A questionnaire was administered to collect primary data from migrants seeking documentations from the Department of Home Affairs, those remitting funds at taxi ranks or bus terminals, and those remitting through commercial banks and money transfer operators. 275 responses were analysed using a Likert rating scale format of 1 (highest) to 5 (lowest). Regulatory requirements of documentary evidence are an important factor influencing the choice of the remittance channel used. Documentation requirement in the formal market causes migrants to be ineligible for the formal channels of remittances and is a factor that influences the choice of remittance channel. Restrictive visa requirements could easily push migrants to become illegal aliens which further deny them access to formal remittance channels. The paper adds to the academic literature on the determinants of remittance channels in Africa. Understanding the relevant issues could assist regulatory authorities to restructure the remittance market with a view to encouraging migrant workers to enter the formal financial system.
The Relationship between Household Debt and Consumption Spending in South Africa
Authors: Nkala Patience , Tsegaye Asrat
Published: May 2017

Consumption has been and remains the main contributor to gross domestic product (GDP) growth in South Africa. Household debt on the other side has remained high over the years. These two economic indicators are a reflection of the well-being of an economy. This study thus examined the relationship between household debt and consumption spending, for the period between 1994 and 2013. The Johansen cointegration technique and the Vector error correction model (VECM) were utilised to test the long run and short run relationships between the variables. The Granger causality test was also employed to test the direction of causality between the variables. Results from this study have revealed that a relationship exists between household debt and consumption spending in South Africa and they have also showed that this relationship flows from household debt to consumption spending. The implications of these results are that consumption spending may be increased through other measures rather than through increasing debt. The study therefore recommends that policy makers avail more investment opportunities for households and to also create employment in a bid to increase the income of households which can then be used to increase household consumption rather than the use of debt.
A novel carbon paste electrode based on nitrogen-doped hydrothermal carbon for electrochemical determination of carbendazim
Authors: Kalijadis Ana , Djordjevic Jelena , Papp Zsigmond , Jokic Bojan , Spasojevic Vuk , Babic Biljana , Trtic-Petrovic Tatjana
Published: May 2017

In this work, a new carbon paste electrode, prepared from nitrogen- -doped hydrothermal carbon (CHTCN) was applied for the electrochemical detection and determination of carbendazim fungicide. CHTCN samples with the nominal nitrogen content 0.05?0.5 wt. % in glucose precursor were prepared by simple, low-cost synthesis with the accompanying carbonization to 1273 K. The presence of nitrogen in CHTCN samples was confirmed by elemental analysis. Characterization of CHTCN as material for carbon paste electrode was achieved by cyclic voltammetry measurement of the Fe(CN)6 3-/4- redox couple. The results showed that best electrochemical response was obtained from the sample with a nominal nitrogen concentration of 0.1 wt. % and with tricresyl phosphate as a binder. During the development of a differential pulse stripping voltammetric method for carbendazim determination applying new electrode, the following experimental parameters were studied: the sort and amount of binding liquid, the effect of pH, accumulation potential and accumulation time. Under optimal conditions, the electrode offered linearity in the wide concentration range from 25 to 490 ng cm-3 and an estimated detection limit of 1.21 ng cm-3. Moreover, the electrode showed good stability, high selectivity and satisfactory anti-interference ability. Finally, the developed method was successfully applied for the determination of carbendazim traces in spiked tap and river water samples.
Aplicación de recubrimientos multicapa para el mejoramiento de la productividad de las empresas
Authors: Nieto Jair Eugenio , Moreno Chávez Luis Henry , Amaya Hoyos César Andrés
Published: May 2017

El objetivo del presente trabajo es introducir al lector en el área de los recubrimientos multicapa los cuales se vislumbran como una solución efectiva ante el problema del desgaste de diversas herramientas o dispositivos. Inicialmentese hace una revisión en la cual se muestran las razones que hicieron de los recubrimientos duros algo indispensable en muchos sectores industriales. A continuación se comentará acerca de los sistemas multicapa y sus bondades en cuanto al incremento de sus propiedades mecánicas para finalmente mostrardos casos reales de aplicación de este tipo de recubrimientos y los resultados obtenidos.
Análisis de corrosión y tribológico de capas delgadas metálicas de Ti y aleación titanio – circonio depositadas por DC magnetrón sputtering no reactivo sobre acero inoxidable de aplicación médica
Authors: Ruden Alexander , González Juan Manuel , Calderón Wilmar , Alonso Falleiros Neusa , Sequeda Federico
Published: May 2017

Recubrimientosencapadelgadadetitanio(Ti)yaleacióntitanio – circonio(Ti-Zr)sedepositaronsobresustratosdeaceroinoxidableAISI304porlatécnicaPVD – DCMagnetronSputteringNoReactivoenambientedeargón,conblancosprecursoresdeTicon99,99%depurezayaleaciónTi-Zr(70/30),serealizaronmedidasdecorrosiónytribologíaparalosmencionadosrecubrimientos;observandocurvaspotenciodinámicassedeterminoelpotencialdecorrosiónydepicaduraparaelaceroylascapasdelgadasusandosoluciónelectrolíticadeNaCl3,5%p/putilizandounelectrododeHg/KClsaturadoatemperaturade37C(temperaturacorporalhumana),losresultadosmuestranquelosrecubrimientosincrementanelpotencialporpicaduraaumentandolavidaútildelsustrato.AtravésdeunsistemaBallonDiscsedeterminoelcoeficientedefricción(COF)ylatasadedesgasteparalossistemasAISI304,TiyTi-30Zrobservandocomportamientotribológicometálico.AnálisismorfológicodelapistadedesgasteyformadepicaduradelacorrosiónfuellevadoacabomedianteMicroscopiaÓptica.
Adecuación tecnológica de un torno Compact 5 CNC a través de un PC
Authors: Muriel Escobar José Agustín , Giraldo Giraldo Ernesto
Published: May 2017

El siguiente articulo presenta la adecuación tecnológica realizada en un torno CNC Compact 5, al que se le efectuaron varias modificaciones relacionadas con la instalación de sensores en los carros longitudinal y transversal, el diseño de tarjetas de control y potencia y el diseño de una interfaz usuario-máquina para la carga de programas y simulación de trayectorias antes de realizar el proceso de maquinado.
Pequeñas y microcentrales hidroeléctricas: alternativa real de generación eléctrica.
Authors: Sierra Vargas Fabio Emiro , Sierra Alarcón Adriana Fernanda , Guerrero Fajardo Carlos Alberto
Published: May 2017

En este papel se pretende exponer la revisión realizada a la información existente de Pequeñas Centrales Hidroeléctricas (PCH), concentrando la descripción en tres aspectos: las turbinas más usadas, las características de los generadores y una breve descripción de la legislación colombiana respecto a la pequeña generación. Esta revisión también abarca una corta descripción de los elementos constitutivos y del desarrollo de las PCH en Colombia.
Evaluación de impacto ambiental producido por el uso de cocinas tradicionales en el área de conservación regional Vilacota-Maure de la región Tacna
Authors: Torres Muro Hugo Alfredo , Agreda Paredes Jesús Natividad , Polo Bravo Carlos Armando
Published: May 2017

El 70 % de la población de las zonas rurales, interandinas y altoandinas en el Perú usa biomasa para calefacción, cocción y otras labores artesanales ycostumbristas. Es necesario disponer de datos sobre la extracción, el consumo de biomasa y los impactos que pueden estar provocando, para planificar suproducción y utilización sostenibles. Este trabajo es producto de varios años de investigación. Las condiciones geográficas, climáticas y culturales de la zona en estudio impiden realizar unaestadía prolongada para la recolección de información de fuentes primarias; sin embargo, la estimación del consumo de leña y la valoración cuantitativa ycualitativa de impactos ambientales en esta zona, contribuye a llenar un vacío de información.Los resultados obtenidos permiten concluir que el uso de leña en el área de estudio, está provocando impactos ambientales negativos de consecuencias locales y globales. Las autoridades regionales y locales deben planificar encorto plazo un programa con tecnologías limpias y renovables para solucionar este problema.
Transferencia tecnológica, capital humano y cooperación: factores determinantes de los resultados innovadores en la industria manufacturera en Colombia 2007-2008
Authors: González CampO Carlos Hernán , Hurtado Ayala AndreA
Published: May 2017

La inversión en tecnología y capital humano y en las redes de cooperación, juega un papel importante en el desarrollo del proceso innovador de un país;así lo prueban las diferentes perspectivas sobre innovación, incluida la teoría de desarrollo endógeno. Con la información de la IV Encuesta de Desarrollo e Innovación Tecnológica, realizada en Colombia para el periodo 2007-2008, los autores utilizan un método de regresión lineal que permite definir las relaciones causales entre las variables mencionadas. Los resultados establecen que variables como tecnología, relaciones de cooperación e inversión en capital humano, determinan los resultados innovadores de la industria manufacturera colombiana, los cuales son mejores cuando se establecen relaciones de cooperación con otras entidades que apoyan la innovación y cuando se invierte en formación del capital humano.
Modelo basado en redes neuronales para predecir las emisiones en un motor diésel que opera con mezclas de biodiésel de higuerilla
Authors: Narváez Fabio , Sierra Vargas Fabio Emiro , Montenegro Mier Manuel Antonio
Published: May 2017

En este documento se explican algunos métodos de identificación de sistemasno lineales mediante el uso de redes neuronales artificiales. También se planteaun modelo basado en redes neuronales Feed Forward supervisadas, desarrolladopara identificar y predecir el comportamiento de las emisiones volumétricas dela combustión de un motor diésel estacionario en función de dos variables deentrada: la carga del motor y la mezcla de biodiésel de higuerilla. El entrenamientode la red neuronal y la validación del modelo se realizaron mediante elprograma NNModel.
Sistema internacional de unidades de medida (SI)
Authors: Cedeño Orlando
Published: May 2017

Un tema tan elemental en metrología como es el de las unidades de medida,causa todavía estragos. Los programas de metrificación en los EstadosUnidos avanzan a pasos agigantados; sin embargo, ¿qué podrá pasar con lospaíses en vías de desarrollo cuando Estados Unidos cambie la infraestructurade producción al sistema métrico? Se comentan situaciones en Colombia, parareflexionar en las organizaciones, especialmente en la academia para la educaciónmetrológica.
Simulación computacional de la estructura FCC del CrN
Authors: Ruden Muñoz Alexander , González Carmona Juan Manuel , Restrepo Parra Elisabet
Published: May 2017

Se sintetizó el recubrimiento en capa delgada de CrN por la técnica de Magnetron Sputteringsobre un sustrato de silicio orientado en la dirección (111). Se analizó estructuralmente usando difracción de rayos X (XRD, por el término en inglés) y espectroscopia Raman, demostrando la fase cúbica para este material cerámico. Se utilizó la Teoría de Funcionales de Densidad (DFT, por el término en inglés) de la estructura cubica del CrN. A partir de simulación computacional, se observó la estabilidad por la suma de cargas de Mulliquen equivalente a cero y la hibridación de este compuesto con orbitales característicos sp, además de la identificación de la componente pdel nitrógeno.
Estudio comparativo de conservación de raíces de yuca (Manihot esculentaCrantz) recubiertas con cera natural y parafina
Authors: Medina Jiménez Sabrina , García Toro Luisa María , Vélez Pasos Carlos , Alcalá Lisímaco Alonso , Fernández Quintero Alejandro
Published: May 2017

Las  raíces  de  yuca  son  muy  susceptibles  al  deterioro  fisiológico,  ya  que después de dos o tres días de cosechadas no son aptas para el consumo. Por esta razón, se han desarrollado diversos métodos de conservación como, por ejemplo, el recubrimiento de la raíces con parafina, el cual extiende la vida útil del producto hasta 15 días. Este método de conservación con parafina presenta desventajas desde el punto de vista ambiental, debido a que es un hidrocarburo derivado del petróleo y, además, se aplica en caliente (temperatura mayor a 120 °C). Por esto, es importante buscar alternativas de conservación amigables con el ambiente. En el presente trabajo se evaluó la efectividad del recubrimiento de raíces de yuca con cera natural como posible sustituto al uso de parafina en la conservación del producto. Los resultados mostraron que la cera natural es igual de efectiva que la parafina en la conservación de las raíces, puesto a que retrasa el deterioro fisiológico, la pérdida de materia seca y la pérdida de peso. Por lo tanto, se demostró que la cera es una buena alternativa para la conservación del producto, como sustituto de la parafina.
Análisis de falla del disco de embrague de un camión de 2 ton
Authors: Perea Salcedo Diego León
Published: May 2017

Este artículo muestra el análisis de la falla presentada en el disco de embrague de un camión para transporte de 2 Ton. El elemento que presentó la fractura estaba fabricado de acero para resortes de alto carbono. Aunque la zona de falla era muy delgada y de difícil interpretación, el examen de la superficie de fractura reveló marcas chevron y presencia mínima de marcas de playa muy tenues. La parte de falla (cushioning plate), fabricada de acero al carbono 1070 templado, estaba sometida a esfuerzos alternantes cortantes y flexión. La falla final fue causada por carga de impacto.
Uso de nanopartículas de sílice para la estabilización de finos en lechos empacados de arena Ottawa
Authors: Mora Mera César , Franco Ariza Camilo Andrés , Cortés Farid Bernardo
Published: May 2017

Las partículas finas débilmente cementadas a la matriz porosa pueden ser liberadas y movilizadas, causando reducciones en la porosidad y permeabilidad de un yacimiento y disminuyendo el recobro de petróleo. Con el fin de determinar el daño de formación por migración de finos y dar una posible solución a este problema, se desarrolló un sistema de adsorción en lechos empacados en los cuales se simuló experimentalmente la estabilización de los finos mediante el uso de nanopartículas. Los lechos adsorbentes usados fueron preparados con arena Ottawa y esferas de vidrio (radio promedio de 0,53 mm). Se usaron tres lechos de arena: uno sometido a un proceso de lavado (lecho humectable al agua), otro sometido a un proceso de daño usando un crudo colombiano extrapesado (lecho humectable al aceite) y un último compuesto de arena tratada con nanopartículas de sílice (5-15 nm). Con las esferas de vidrio se prepararon dos lechos: uno con las esferas lavadas y otro con las esferas impregnadas con nanopartículas. La suspensión de finos se preparó con nanopartículas de alúmina (50 nm) y agua destilada. Se observó que los lechos tratados con nanopartículas seguían los patrones idealizados de las curvas de ruptura, indicando que las nanopartículas de sílice inhiben la migración de finos debido a su alta capacidad adsortiva.
Posibilidades de fabricación con el polietileno aluminio obtenido del reciclaje de envases multicapas
Authors: Hidalgo Salazar Miguel A. , Neves Fernando Luiz , Baena Eduardo
Published: May 2017

En el presente artículo se muestra una serie de posibilidades de fabricación con el polietileno aluminio obtenido del proceso de reciclaje de envases multicapas de Tetra Pak, los cuales comenzaron a desarrollarse desde el año 2007, en conjunto con la empresa Innopac k de Cali y el Grupo de Investigación en Tecnologías para la Manufactura GITEM de la Universidad Autónoma de Occidente, con el apoyo de la gerencia ambiental de Tetra Pak Colombia. Entre otras, se presenta una síntesis de varias posibilidades de separación de los materiales que conforman el polietileno aluminio (LDPE-Al) resultante del proceso de hidropulpado de los envases Tetra Pak reciclados, así como las posibilidades de procesamiento del LDPE-Al realizadas por el GITEM, incluyendo técnicas como: moldeo por compresión en prensa de platos calientes, extrusión, inyección, rotomoldeo, fabricación de compuestos reforzados con fibras naturales y mezclas con otros polímeros y la obtención del LDPE-Al pulverizado. Estos estudios se han hecho con el fin de favorecer principalmente el reciclaje de envases Tetra Pak en grandes volúmenes, especialmente al mostrar las diferentes posibilidades de aplicación de los subproductos del proceso de hidropulpado, se identificaron aspectos relevantes en los procesos de transformación del LDPE-Al. Se ha encontrado, a nivel de laboratorio, que es relativamente sencilla la inclusión del LDPE-Al en diferentes procesos de manufactura, y se resalta que las mejores posibilidades observadas pueden estar en el desarrollo de nuevos materiales compuestos reforzados con fibras naturales, para sustituir productos de madera en diferentes industrias, incluyendo aplicaciones en la industria automotriz.Aunque hoy en día es limitado el volumen de reciclaje en Colombia, se espera que en las próximas décadas mejore la jerarquía de recolección de envases Tetra Pak sobre la gestión de los residuos de origen plástico en el país.
Revisión de las implicaciones ocupacionales por exposición al plomo.
Authors: Pájaro Castro Nerlis Paola , Maldonado Rojas Wilson , Pérez Gari Narcisa Esther , Díaz Cuadro Jhon Albeiro
Published: May 2017

El plomo, considerado uno de los metales tóxicos más comunes en el medio ambiente, es frecuentemente utilizado en el mundo para la fabricación de armas, baterías y aditivos para la gasolina, entre otras aplicaciones. La exposición cró- nica a este contaminante es un problema de salud pública que afecta sistemas importantes como el nervioso, el reproductivo y el circulatorio. En varios países la búsqueda de materiales que reemplacen el plomo ha sido implementada con buenos resultados. En Colombia no existen regulaciones nacionales concretas que garanticen el desempeño ocupacional en ambientes libres de plomo, por lo que se hace necesaria la creación de regulaciones que permitan minimizar el riesgo de exposición a este metal tóxico.
Resistencia a la corrosión de recubrimientos a base de titanio y circonio producidos por magnetrón Sputtering DC
Authors: Gómez Hernández Diana Alexandra , Jurado Ortiz Paola Alejandra , De la Roche Yepes Jhonattan , Ruden Muñoz Alexander , González Juan Manuel , Sequeda Osorio Federico
Published: May 2017

Se depositaron recubrimientos de nitruro de titanio (TiN y TiN/Ti) y nitrurode titanio circonio (TiZrN) sobre aceros AISI 304 y 316L por medio de la técnicamagnetrón Sputtering DC para evaluar sus propiedades superficiales y mecánicas, así como la resistencia a la corrosión. El análisis estructural realizado por mediode difracción de rayos X (XRD) mostró que todos los materiales estudiados cris-talizaron en una estructura f.c.c, con orientación preferencial en plano de Bragg (111); el recubrimiento de TiZrN, muestra estrés a la compresión por la inclusiónde átomos de Zr en la estructura del TiN y se observa ensanchamiento en lospicos de difracción debido a la presencia de TiN en la película. Las características superficiales medidas por perfilometría (rugosidad Ra y espesor) muestranvalores de Ra inferiores a 100 nm, típicos de capas delgadas sintetizadas por estemétodo. Los espesores obtenidos varían desde 364,50 nm hasta 580,25 nm. Usandonanoindentación se obtuvieron valores de dureza de capa de TiN, TiN/Ti y TiZrN de 16, 173, 18, 524 y 17, 307 Gpa respectivamente; la evaluación de la resistencia ala corrosión (polarización tafel) muestra que la velocidad de corrosión del acerodisminuye cuando la superficie es protegida con un recubrimiento, hecho que sedeterminó por la reducción de la tasa de corrosión.
Power Generation Limits in Thermal, Chemical and Electrochemical Systems
Authors: S. Sieniutycz
Published: May 2017

Power generation limits are evaluated via optimization for
various energy converters, such like thermal, solar, chemical, and
electrochemical engines, in particular fuel cells. Thermodynamic
analyses lead to converters’ efficiencies, which help to solve problems
of optimal upgrading and downgrading of resources. While methods of
static optimization, i.e. differential calculus and Lagrange multipliers,
are sufficient for steady processes, dynamic optimization applies the
variational calculus and dynamic programming for unsteady processes.
In reacting systems chemical affinities constitute prevailing
components of an overall efficiency, thus flux balances are applied to
derive power in terms of active parts of chemical affinities.
Methodological similarity is observed when treating power limits in
flow thermal machines and fuel cells. The examples show power
maxima in fuel cells and prove suitability of a thermal machine theory
to chemical and electrochemical systems. The main novelty of
contribution in the fuel cell context consists in introducing an effective
change of Gibbs free energy between products p and reactants s which
takes into account lowering of voltage and power caused by the
incomplete conversion of the overall electrochemical reaction.
Biogas Energy: Unexplored Source of a Renewable Energy in Jordan
Authors: Abu-Hamatteh Z.S.H.  , Al-Jufout, Saleh  , Abbassi B  , Besieso, M. S
Published: May 2017

Jordan is a non-oil producing country. Its basic energy requirements are obtained from imported oil and natural gas from different sources. Domestic natural gas covers only 4% of the Kingdom’s energy needs. Energy import costs create a financial burden on the national economy. Jordan spends more than 25% of its GDP on the purchase of energy. Considerable efforts have been made and great progress has been achieved in the application of solar, wind, biogas and hydro energy utilization. This paper explores the potential of biogas as renewable energy in developing countries including Jordan, where access to basic clean energy services is essential for sustainable development. A techno–economic feasibility study for electric power generation from municipal solid waste was carried out in cooperation with the UNDP and the UN Global Environmental Facility has approved the award to finance a pilot biogas plant at Amman municipal waste disposal site. The project rated capacity is 1MW and due to the successful operation, the project was expanded to 3.5MW.
Online Gearbox-Load-Monitoring to Increase Gearbox Reliability
Authors: Dr. Volker Kreidler  , Dipl.-Ing. Holger Daum
Published: May 2017

Failures    of    Gearboxes    within    Offshore-Windpark-Applications    lead    to    long    downtimes    and    high    repair/replacement costs. The strategic goal for Offshore-Windturbines is to avoid gearbox failures at all. This goal is  only  then  realistic  if  the  real  loads  and  forces  are  measured in real time at high frequencies by the gearbox. The  paper  will  report  about  a  Mechatronic  gearbox-prototype of the 1,5 MW-class with integrated contactless load-sensors,     analytic     electronics/software     and     a     highspeed  fieldbus-interface  for  communication  with  the  turbine  controller.  The  full  integration  of  mechanics,  electronics, software and communication.
Analiza koncentracji sekcji Polskiej Klasyfikacji Działalności w wybranych regionach Polski
Authors: Piórkowska Paulina
Published: May 2017

Motywacja: Analiza koncentracji działalności gospodarczej w wybranym regionie Polski, w odniesieniu do obszaru referencyjnego, jest przydatna w procesie decyzyjnym w zakresie wyboru miejsca lokalizacji danego przedsiębiorstwa. Umożliwia ona także sprawdzenie perspektyw rozwojowych wybranych regionów.Cel: Celem artykułu jest analiza koncentracji sekcji Polskiej Klasyfikacji Działalności (PKD) w Centralnym i Południowo-Zachodnim Regionie Polski. Na podstawie liczby nowo zarejestrowanych podmiotów gospodarczych obliczono wskaźnik lokalizacji ukazujący koncentrację przestrzenną przedsiębiorstw w tych obszarach.Wyniki: Na podstawie przeprowadzonej analizy możliwe było wskazanie sekcji według PKD, które były najczęściej wybierane przez przedsiębiorców. Wskazano także te sekcje, które zawierają się w najbardziej pożądanej klasie wskaźnika lokalizacji ze względu na jego wysoki poziom i korzystną dynamikę. Są one fundamentem rozwoju gospodarki regionalnej w Centralnym i Południowo-Zachodnim Regionie Polski.
Mathematical Uncertainty Relations and their Generalization for Multiple Incompatible Observables
Authors: Nguyen Hung Quang , Bui Tu Quang
Published: May 2017

We show that the famous Heisenberg uncertainty relation for two incompatible observables can be generalized elegantly to the determinant form for N arbitrary observables. To achieve this purpose, we propose a generalization of the Cauchy-Schwarz inequality for two sets of vectors. Simple consequences of the N-ary uncertainty relation are also discussed.

Keywords: Generalized uncertainty relation, Generalized uncertainty principle, Generalized Cauchy-Schwarz inequality.
Developing the Program Evaluation Utility Standards: Scholarly Foundations and Collaborative Processes
Authors: Yarbrough Donald B.
Published: May 2017

Abstract: Developing the third edition of the program evaluation utility standards required multilevel collaborations among task force members, members of the Joint Committee on Standards for Educational Evaluation, sponsoring organizations, and hundreds of involved stakeholders. The scholarship on evaluation use, influence, and collaboration was foundational for the utility standards and materials accompanying them and equally important for informing the processes guiding utility standards development. This article emphasizes the foundational role of this recent scholarship and the roles played by all who collaborated in planning and implementing the utility standards development processes.
Backstabbing swordfish: a rare cause of traumatic hemiparesis
Authors: Sriram Prabu Rau , Tsin Jien Timothy Cheng , Sellamuthu Pulivendhan
Published: May 2017

Swordfish attacks on humans are uncommon, with only a few case reports available in the current literature. The authors report the first known case of a penetrating spinal injury from a swordfish, in which the patient presented with a small stab wound and hemiparesis. The presentation of a fisherman with hemiparesis and a harmless-looking stab wound must alert clinicians to the possibility of penetrating swordfish injuries to the spine.
Cerebral hemorrhage in monozygotic twins with hereditary hemorrhagic telangiectasia: case report and hemorrhagic risk evaluation
Authors: Rattani Abbas , Dewan Michael C. , Hannig Vickie , Naftel Robert P. , Wellons John C. , Jordan Lori C.
Published: May 2017

The authors present a case of monozygotic twins with hereditary hemorrhagic telangiectasia (HHT) who experienced cerebral arteriovenous malformation (AVM) hemorrhage at a very young age. The clinical variables influencing HHT-related AVM rupture are discussed, and questions surrounding the timing of screening and intervention are explored. This is only the second known case of monozygotic HHT twins published in the medical literature, and the youngest pair of first-degree relatives to experience AVM-related cerebral hemorrhage. Evidence guiding the screening and management of familial HHT is lacking, and cases such as this underscore the need for objective and validated protocols.
Variation in management of in-hospital newborn falls: a single-center experience
Authors: Kahn Doron J. , Fisher Paul D. , Hertzler Dean A.
Published: May 2017

OBJECTIVE

There are only 3 small case series in the literature that report on the management of in-hospital newborn falls (NFs), and recommendations are unclear. The authors performed a retrospective review to determine outcome and differences in management and to understand why management of NFs varies at their institution.

METHODS

All NFs occurring within the authors’ institution over a 3.5-year period were reviewed. Post-fall management and outcomes of each incident were compared.

RESULTS

There were 24 NFs out of 40,349 deliveries (5.9 NFs/10,000 deliveries). The mechanism of injury was nearly identical in 22 of 24 falls (the newborn fell to the floor from a parent in a bed or chair), and physical examination findings were normal or benign in all cases. Unexplained management variation based solely on clinician preference was noted, including observation only (in 13 cases), skull radiograph (in 7), head CT scan (in 6), bone survey (in 4), and head ultrasound examination (in 1), with some babies having more than 1 study. Two babies had nondepressed linear parietal fractures diagnosed by skull radiograph, and 2 babies had small subdural hemorrhages diagnosed by head CT scan. All 24 babies had normal findings on examination at discharge.

CONCLUSIONS

There is a high incidence of nondepressed linear parietal skull fractures associated with NFs. However, since associated intracranial injury is uncommon, imaging studies may not be routinely performed. Neonatal intensive care unit admission, head CT, and neurosurgical evaluation are reserved for the rare baby with abnormal physical examination or neurological findings.
Transformations of India after the Indian Mutiny
Authors: ní Fhlathúin Máire
Published: May 2017

This chapter explores British responses to the events of the Indian Mutiny/Rebellion of 1857, and to the rise of Bengal nationalism towards the end of the nineteenth century. This period is characterised by a British turning away from both ‘home’ and indigenous India and towards an insular colonial mindset. An examination of some representative texts shows that at the same time, the literature of the colony engages in a set of transformative narratives of India and the British role in India. The tropes and themes of depictions of India in the earlier pre-Mutiny period are now co-opted and turned to the depiction of British heroism and British sacrifice, in a process which also involves the incorporation of aspects of a stereotypically Indian character into an evolving ideal figure of British colonial rule, whose femininity makes it paradoxically impossible for her to be accorded a place in the male-dominated society of the colony.
To Temper an Imminent Eschatology: The Contributions of al-Mahdī and Qāḍī l-Nuʿmān
Authors: Velji Jamel A.
Published: May 2017

Chapter five focuses on the ways in which the first Fatimid caliph al-Mahdi and the most important ideologue of the Fatimid State, Qāḍī l-Nuʿmān, reinterpreted the identity of the eschatological figure and his placement in sacred history while simultaneously arguing for the Fatimids’ right to rule. Two texts are central to this chapter’s analysis: the caliph al-Mahdi’s letter to his Yemeni community, and Qāḍī l-Nuʿmān’s taʾwīl of his own book of laws, the Taʾwīl al-dāʿāʾim. The latter book has not been translated and has only received scant scholarly attention. Yet it is a fascinating source because it is a book whose symbolic interpretations were authorized by the imam himself and read only to initiates. This chapter shows how al-Nuʿmān’s taʾwīl of ritual practices becomes a powerful mechanism for reinterpreting the temporal linearity associated with an imminent mahdist expectation.