Characteristics of Pump Performance in Major Irrigated Areas of California

Well pump tests (12,876) in three Central California groundwater basins were characterized and described according to their spatial distribution. The average overall pumping plant efficiency (wire-water, not including column losses and velocity head) was about 56%. Characteristics such as drawdown, total dynamic heads, kW, and flow rate vary greatly between pumps within and between sub-basins. This is the first well pump characterization of its type in California, although irrigation pump tests have been conducted for over 70 years in California. This paper provides a summary of the spatial variation of well pump performance and characteristics

Relative recoilless F-factors in REFeO3 (RE = rare-earth La, Pr, Nd and Sm) orthoferrites synthesized by self-combustion method

ABSTRACT: In this work, rare-earth orthoferrites polycrystalline compounds REFeO3 (REFO) with RE = rare-earth La, Pr, Nd and Sm were synthesized by the self-combustion method. A direct correlation between the magnitude of the magnetic hyperfine field and the FeAO1AFe bond angles was observed. From transmission Mössbauer spectra recorded at room-temperature, relative recoilless F-factors for these REFO compounds were estimated. The method applied to perform this calculation was based on the determination of two subspectral areas present in a mixture of known amounts of the compound under study and a standard sample (a-Fe). For that purpose spectra were thickness-corrected and fitted using lorentzian lines. The so obtained factors were F-REFeO3 (RE = rare-earth La, Pr, Nd and Sm): 1.30 ± 0.02, 1.08 ± 0.04, 1.15 ± 0.05, 1.18 ± 0.08 respectively. The absolute recoilless factors obtained by this method had an average relative error around 11% in comparison with the values predicted by the Debye model

Evaluación de combinaciones de aceites esenciales y aceites esenciales con hidrosoles sobre actividades antimicrobianas y antioxidantes]

International audienceContext: Essential oils (EO) are commonly extracted from plants by steam distillation in which an aqueous phase called hydrosol (HD) is obtained. Unlike EO, hydrosol studies have been limited despite the interest of the food, cosmetic and phytotherapeutic industries to find natural preservative alternatives to synthetic ones. Aims: To evaluate the in vitro antimicrobial and antioxidant efficacies of combinations of essential oils (EOs) and essential oils and hydrosols (HDs) of Lippia alba, Rosmarinus officinalis, and Thymus vulgaris. Methods: The EOs and HDs were characterized by gas chromatography with flame ionization detector and gas chromatography coupled with mass spectrometry. Then, they were screened against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus niger using the microdilution method for the four first strains and the agar diffusion method for Aspergillus niger. Antioxidant capacity was evaluated using ABTS method. Results: Interactions between essential oils, and essential oils and hydrosols were found to be as microbicide, and for the first time, antioxidant using the fractional inhibitory concentration. When compared with individual EOs, EO-EO combinations diminished the microbicide minimum concentration. Conclusions: The Thymus vulgaris EO-HD combination, in comparison with individual extracts, diminishes by four times the MBC against Escherichia coli and decrease by half their antioxidant capacity.Contexto: Los aceites esenciales (AEs) se extraen comúnmente de las plantas por destilación con arrastre de vapor en la que se obtiene una faseacuosa llamada hidrosol (HDs). A diferencia de los AE, los estudios de los HD han sido limitados a pesar del interés de las industrias alimentaria,cosmética y fitoterapéutica de encontrar alternativas naturales de conservación.Objetivos: Evaluar la eficacia antimicrobiana y antioxidante in vitro de las combinaciones de AEs, AEs e HDs de Lippia alba, Rosmarinus officinalis y Thymus vulgaris.Métodos: Los AEs e HDs fueron caracterizados por cromatografía de gases con detector de ionización en llama y cromatografía de gases acoplada a espectrometría de masas. Luego se realizaron pruebas de detección contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans y Aspergillus niger utilizando el método de microdilución para las cuatro primeras cepas y el método de difusión en agar para Aspergillus niger. La actividad antioxidante se evaluó utilizando el método ABTS.Resultados: Se encontró que las interacciones entre los aceites esenciales, aceites esenciales e hidrosoles eran microbicidas y, por primera vez,antioxidantes usando la concentración inhibidora fraccionada. Cuando se compararon con AEs individuales, las combinaciones AE-AEdisminuyeron la concentración microbicida mínima.Conclusiones La combinación de tomillo AE-HD; en comparación con los extractos individuales, disminuye en cuatro veces el MBC contraEscherichia coli y disminuye a la mitad su actividad antioxidante

Role of imine isomerization in the stereocontrol of the Staudinger reaction between ketenes and imines

Computational–experimental analysis has allowed determining that the stereochemistry of the Staudinger reaction between ketenes and imines is strongly associated with the nature of the imine, which affects the two steps of the reaction. The first step, namely the nucleophilic attack of the sp2-hybridized nitrogen atom of the imine on the sp-hybridized carbon atom of the ketene, is affected by the energetically accessible in situ isomerization patterns of the imine. The second step consists of a conrotatory electrocyclization of the zwitterionic intermediate formed in the previous step. This latter pericyclic step depends on the inward/outward torquoelectronic effects generated by the substituents of the imine. The impact of these factors on the stereochemistry of this reaction has been analyzed kinetically by numerical methods. The results of these simulations are compatible with the experimental results and support these conclusions

Medición de la capacidad de nitrificación mediante la técnica de incubaciones in situ en suelos cultivados con maíz

p.101-114Se realizaron incubaciones de suelo a campo en cilindros con el objeto de mantener la estructura del mismo, recubriéndolos con bolsas de polietileno evitando a sí pérdidas de N por lavado. Se trabajó con suelos de la zona núcleo maicera durante los meses de enero y febrero (Campañas 1982-83 y 1983-84). La producción de nitratos se calculó por diferencia entre la concentración al cabo de un mes de incubación y el contenido inicial. El proceso de mineralización se vio afectado por el tenor hídrico inicial, liberándose del 0,7 al 0,9 por ciento del nitrógeno total. Paralelamente, se realizaron incubaciones de laboratorio en condiciones controladas de temperatura y humedad para los cuales se obtuvieron tasas cuatro veces superiores. No se encontró asociación entre NT, CT, y N hidrolizable con la cantidad de nitratos liberados en condiciones de campo y de laboratorio

Perfil de Personalidad de un Grupo de Estudiantes de Citohistotecnología

By 2012, the National Ministry of Education in Colombia recognized 286 Institutions of Higher Education (IHEs) in the country that offered technical and technological programs. The quality of technicians, technologists, and other professionals is directly related to their performance during secondary and tertiary education. The aim of this paper is to describe the personality profile and academic performance of a group of Cytology and Histology students at a Health Sciences institution of higher education. We performed a descriptive study that included first to third semester students in the Department of Cytology and Histology. We measured socio-demographic variables related to academic achievement and the Gordon Personal Profile-Inventory (GPP-I) test results. This study was approved by the Ethics for Research on Humans Committee at the Fundación Universitaria de Ciencias de la Salud. We analyzed 53 Cytology and Histology students. The average age was 18 years old (IQR 18-21), and the gender distribution was 88.4% female (46/53). The initial grade mean was 3.5 (IQR: 3.3-3.8), with 5 being the maximum in the Colombian grading system, and the mid-career grade was 3.7 (IQR: 3.6-4). We explored the relationship between the place of residence before starting the program, the result of the National Test for Graduates in Colombia (ICFES-SABERPro, comparable to the American SAT), and the academic performance of students. We observed a significant correlation among these variables. Despite there being a number of university departments in the field in Colombia, Cytology/Histology is a poorly known profession, and the skills and abilities together with its range of tasks in the labor market are unknown. Concerning academic performance and its correlation with the GPP-I domains, we observed that there was a direct relationship between starting grade point average and original thinking.En Colombia para el año 2012 fueron reconocidas 286 Instituciones de Educación Superior (IES), las cuales ofertan programas técnicos y tecnológicos. La calidad de los técnicos, tecnólogos y profesionales está relacionada directamente con su desempeño durante el colegio y la carrera. Describir el perfil de personalidad y su desempeño académico de un grupo de estudiantes de Citohistología, en una institución de educación superior de ciencias de la salud. Se realizó un estudio descriptivo, donde se incluyeron estudiantes de primero a tercer semestre de la Facultad de Citohistotecnología. Se midieron variables sociodemográficas, relacionadas con el desempeño académico y resultados de la prueba de inventario de personalidad de Gordon (P-IPG). Este estudio fue aprobado por el comité de ética de investigación con seres humanos de la Fundación Universitaria de Ciencias de la Salud. Se analizaron 53 estudiantes de Citohistología, la mediana de edad fue de 18 años (RIQ: 18-21), la distribución por género fue 46 mujeres (88.4%). La mediana de notas al inicio de carrera fue de 3.5 (RIQ: 3.3-3.8), y mitad de carrera 3.7 (RIQ: 3.6-4). Se exploró la relación entre el lugar de vivienda antes de iniciar el pregrado, el resultado del ICFES-SABERPro y el rendimiento académico, observando una relación estadísticamente significativa. La Citohistotecnología actualmente es poco conocida a pesar de que existen varias facultades en Colombia y no se conoce claramente las destrezas y habilidades de su desempeño en el campo laboral. Con respecto al rendimiento académico y su correlación con los dominios del P-IPG, se observó que había una relación directamente proporcional entre el promedio inicial de carrera y la originalida

Management of a bleeding ulcer by post-esophageal ligation of varices with self expanding metal stents: case report and literature review

Los inicios del manejo del sangrado variceal con compresión directa datan de 1930 por Westphal y colabo- radores. Después, en 1950, se desarrolló el balón de Sengstaken-Blakemore, definido por Panes y colabo- radores como la primera línea de terapia; en 1980, a nivel de várices esofágicas y en várices gástricas, se empleaba el balón de Linton-Nachlass (1, 2). Se presenta el caso clínico de un paciente con cirrosis hepática por hepatitis C, Child B, con várices esofágicas, a las cuales se les realizó ligadura en dos ocasiones por san- grado y en la segunda ocasión por inminencia de ruptura, esta última llevada a cabo dos semanas antes del evento. El paciente muestra un cuadro clínico compatible con hemorragia de vías digestivas altas masiva, con evidencia endoscópica de úlcera esofágica sangrante que no mejora con terlipresina, ni escleroterapia con adrenalina, ni compresión local con balón de acalasia. En consecuencia, como terapia de rescate se decide colocar un stent esofágico metálico autoexpandible parcialmente recubierto (por no contar con totalmente recubierto en el momento), con control parcial del sangrado. Es recomendable el uso del stent como terapia de rescate para el sangrado por várices esofágicas refractarias. Debe emplearse el diseñado especialmente para esta indicación (SX-Ella Danis), como un puente para poder estabilizar al paciente y realizar una terapia definitiva como la TIPS, tal cual como se procedió en un nuestro paciente.Early treatment of bleeding varices with direct compression dates from the work by Westphal et al. in 1930. Later in 1950, Sengstaken-Blakemore developed their balloon which Panes and collaborators defi ned as the fi rst line of therapy for esophageal varices in 1980 while they used the Linton-Nachlass balloon for gastric varices (1, 2). This study presents the clinical case of a patient with liver cirrhosis due to hepatitis C, (Child B) with esopha-geal varices which were ligated on two different occasions because of bleeding. On the second occasion a rupture was imminent and ligation occurred two weeks prior to the event. The patient presented a clinical picture compatible with massive upper gastrointestinal bleeding with endoscopic evidence of a bleeding esophageal ulcer that did not improve with terlipressin, sclerotherapy with adrenaline, or balloon dilatation. Consequently, it was to use a partially covered self-expanding metal esophageal stent for salvage therapy since a completely covered stent was not available at that time. Stenting achieved partial control of bleeding. We recommend the use of stenting with a stent specifi cally designed for this indication (SX-Ella Danis) as salvage therapy for refractory bleeding from esophageal varices. The stent can be used as a bridge to stabilize the patient in order to perform TIPS as the defi nitive treatment, as in the case of our patient

Phytochemical, antioxidant and antimicrobial parameters of essential oils and hydrosols of colombian Thyme and Rosemary obtained using two different steam distillation methods

Two procedures of steam distillation of Rosmarinus officinalis and Thymus vulgaris were compared by phytochemical, antioxidant and antimicrobial analysis of their respective essential oils and hydrosols using respectively GCFID and GCMS analysis, free radical scavenging activity on ABTS and dilution and diffusion method against 3 bacteria and 2 fungi. Differences in bioactivity results are discussed taking into account changes in molecular content of essential oils and hydrosols obtained by the two different distillation methods. Although no significant difference was observed between the two procedures with Rosmarinus officinalis, that was not the case with Thymus vulgaris. Significant differences were noted, not only in their respective chemical composition especially with the thymol and p-cymene percentage with respectively a change from 39% with conventional steam distillation to 27% with adapted steam distillation for thymol and from 28% with the first distillation to 37% with the second one for p-cymene. These phytochemical composition changes have an impact on their biological activities results and consequently on the therapeutic activities expected which shows the importance of distillation method selection