EVALUACIÓN DE LA UNIFORMIDAD DE DISTRIBUCIÓN EN CAMPO EN RIEGO POR GOTEO CON AGUAS REGENERADAS: COMPARACIÓN Y PROPUESTA DE UN NUEVO MÉTODO

[EN] Flow distribution uniformity is a parameter used for micro-irrigation evaluation. Different methods describe how to collect data and to calculate the distribution uniformity, such as the procedures developed by Merriam and Keller (1978), ASAE (1998) and Burt (2004). The main difference between these methods is the number and location of the drip emitters used for calculating the distribution uniformity. Nowadays, with increasing use of precision technologies, an alternative method is proposed to estimate distribution uniformity in real time and without using the manpower required by this time-consuming task. This method consists in using flow and pressure data collected by the devices installed in the drip irrigation unit. The proposed procedure will also allow to evaluate subsurface drip irrigation systems, which distribution uniformity otherwise would be very difficult to determine frequently. The evolution of the results obtained by the proposed method according to the irrigation time is more similar with that obtained by Burt’s (2004) method than that obtained following Merriam and Keller’s (1978) method.[ES] La uniformidad de distribución de caudales es una medida de evaluación de los sistemas de riego por goteo. Existen distintos métodos de evaluación de campo descritos para su determinación, entre los cuales destacan los de Merriam y Keller (1978), ASAE (1998) y Burt (2004). La principal diferencia entre estos métodos está en la localización y cantidad de emisores que se utilizan para el cálculo de la uniformidad. En la situación actual de aumento de la utilización de tecnologías de precisión, se propone una alternativa a los métodos existentes consistente en la utilización de registros de caudal y presión proporcionados por distintos medidores instalados en la subunidad de riego, permitiendo estimar la uniformidad de distribución de caudales en tiempo real y sin necesidad de utilización de mano de obra para esta laboriosa tarea. La nueva metodología permitiría, además, evaluar instalaciones de goteo enterrado que de otra manera sería complicado de medir frecuentemente. La evolución de los resultados obtenidos en función de las horas de riego con el método presentado es más parecida a la que se consigue con el método de Burt (2004) que a la obtenida con el método de Merriam y Keller (1978).Duran-Ros, M.; Arbat, G.; Pujol, J.; Barragán, J.; Ramírez De Cartagena, F.; Puig-Bargués, J. (2015). EVALUACIÓN DE LA UNIFORMIDAD DE DISTRIBUCIÓN EN CAMPO EN RIEGO POR GOTEO CON AGUAS REGENERADAS: COMPARACIÓN Y PROPUESTA DE UN NUEVO MÉTODO. En XXXIII CONGRESO NACIONAL DE RIEGOS. Valencia 16-18 junio de 2015. Editorial Universitat Politècnica de València. https://doi.org/10.4995/CNRiegos.2015.1526OC

Level of Physical Activity and Its Relationship to Self-Perceived Physical Fitness in Peruvian Adolescents

Background: Physical activity and physical fitness play an important role in adolescence. Both are considered to be indicators of the current and future health status of young adults. The main objective of this article was to report the normative values of the Physical Activity Questionnaire for Adolescents (PAQ-A) and the International Fitness Scale (IFIS) instruments in Peruvian school adolescents. Methods: A sample of 1229 participants (622 girls and 607 boys) aged between 12 and 17 years was used. The type of study was descriptive-comparative. All measures used were obtained by means of self-administered instruments. The PAQ-A was used to assess the level of physical activity and the IFIS to assess the self-perceived physical fitness level of the adolescents. Results: It was observed that the PAQ-A questionnaire results obtained from the total sample was 2.34; significantly higher for boys (2.41) compared with girls (2.27). For the IFIS, the total score was 3.07, with boys obtaining 3.13 and girls 2.97. Conclusions: It was concluded that there was a direct relationship between the level of PA and self-perceived PF in Peruvian adolescents. Furthermore, adolescent boys were more physically active than girls and they had a better self-perceived PF with the exception of flexibility. Finally, there was a higher weight category involved at the lower level of PA

Cabotegravir for HIV Prevention in Cisgender Men and Transgender Women

Background: Safe and effective long-acting injectable agents for preexposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) infection are needed to increase the options for preventing HIV infection. Methods: We conducted a randomized, double-blind, double-dummy, noninferiority trial to compare long-acting injectable cabotegravir (CAB-LA, an integrase strand-transfer inhibitor [INSTI]) at a dose of 600 mg, given intramuscularly every 8 weeks, with daily oral tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) for the prevention of HIV infection in at-risk cisgender men who have sex with men (MSM) and in at-risk transgender women who have sex with men. Participants were randomly assigned (1:1) to receive one of the two regimens and were followed for 153 weeks. HIV testing and safety evaluations were performed. The primary end point was incident HIV infection. Results: The intention-to-treat population included 4566 participants who underwent randomization; 570 (12.5%) identified as transgender women, and the median age was 26 years (interquartile range, 22 to 32). The trial was stopped early for efficacy on review of the results of the first preplanned interim end-point analysis. Among 1698 participants from the United States, 845 (49.8%) identified as Black. Incident HIV infection occurred in 52 participants: 13 in the cabotegravir group (incidence, 0.41 per 100 person-years) and 39 in the TDF-FTC group (incidence, 1.22 per 100 person-years) (hazard ratio, 0.34; 95% confidence interval, 0.18 to 0.62). The effect was consistent across prespecified subgroups. Injection-site reactions were reported in 81.4% of the participants in the cabotegravir group and in 31.3% of those in the TDF-FTC group. In the participants in whom HIV infection was diagnosed after exposure to CAB-LA, INSTI resistance and delays in the detection of HIV infection were noted. No safety concerns were identified. Conclusions: CAB-LA was superior to daily oral TDF-FTC in preventing HIV infection among MSM and transgender women. Strategies are needed to prevent INSTI resistance in cases of CAB-LA PrEP failure

Optimización de la dosis de nitrógeno en suelos poco profundos, irrigados, bajo cultivo de maíz

A method of evaluating net nitrogen (N) mineralization in shallow petrocalcic soils, based on N balances in non-fertilized plots, is proposed. During 1999, 2000 and 2001, estimated N mineralized in an irrigated maize crop (6.5 months) in Central Spain was: 73.3, 56.2 and 60.5 kg ha-1, respectively. The relationship between EUF-Norg (organic nitrogen extracted from soil by electroultrafiltration) and mean mineralized N, in this experiment during the three seasons, was 1 mg EUF-Norg 100 g-1 soil equivalent to 30 kg N ha-1. The calibration was applied to EUF-Norg values from soil samples analysed before sowing. These values, together with the mineral N, were used to estimate available N and consequently the optimal N rate. To evaluate the effect of N fertilizer rate on NO3 leaching and in N fertilizer-use efficiency (NFUE) three different rates of N were tested in 2000 and 2001: optimal N rate (NO), conventional N rate (NC) and a control no N (C). The NO rates for the maize crop were 150 and 130 kg N ha-1 in 2000 and 2001, respectively. Nitrogen losses of nitrate due to leaching were lower with NO than with the NC rate of 300 kg N ha-1. The NFUE values were higher for NO at 78.8% and 83.5% in 2000 and 2001, respectively than for NC at 48.7% and 49.3% in 2000 and 2001, respectively). However, in spite of the different levels of applied N, there was no difference in grain yield among treatments.Se propone una metodología para evaluar el nitrógeno (N) mineralizado en suelos petrocálcicos poco profundos, basada en los balances de N en parcelas no fertilizadas. Durante los años 1999, 2000 y 2001 el N mineralizado en un cultivo de maíz irrigado (6,5 meses) en la zona centro de España fue 73,3, 56,2 y 60,5 kg ha-1, respectivamente. La relación observada en este experimento, entre EUF-Norg (nitrógeno orgánico extraído por electroultrafiltración) y el N mineralizado durante los tres periodos de cultivo (valores medios), fue 1 mg EUF-Norg 100 g-1 suelo=30 kg N ha-1. Esta calibración se aplicó a los valores de EUF-Norg correspondientes a las muestras de suelo tomadas antes del cultivo. Para evaluar el efecto de las dosis de fertilizante sobre la lixiviación de nitrato y la eficiencia del uso de fertilizante nitrogenado (NFUE), se determinó el N asimilable y la dosis óptima de N, en base a esta calibración, junto con el N mineral del suelo. Los tratamientos aplicados fueron los siguientes: dosis óptima de N (NO), dosis convencional (NC) y control sin fertilizar (C). Las NO estimadas fueron 150 y 130 kg ha-1, en 2000 y 2001, respectivamente. El nitrato perdido por lixiviación fue menor en la NO que en la NC de 300 kg N ha-1. Los valores de NFUE fueron más altos para NO (78,8% y 83,5% en 2000 y 2001, respectivamente) que para NC (48,7% y 49,3% en 2000 y 2001, respectivamente). Sin embargo, a pesar de las diferencias en las dosis de N aplicadas en ambos tratamientos, no se observó ningún efecto sobre la producción de grano

Pointwise Lipschitz functions on metric spaces

For a metric space X, we study the space D(infinity)(X) of bounded functions on X whose pointwise Lipschitz constant is uniformly bounded. D(infinity)(X) is compared with the space LIP(infinity)(X) of bounded Lipschitz functions on X, in terms of different properties regarding the geometry of X. We also obtain a Banach-Stone theorem in this context. In the case of a metric measure space, we also compare D(infinity)(X) with the Newtonian-Sobolev space N(1,infinity)(X). In particular, if X Supports a doubling measure and satisfies a local Poincare inequality, we obtain that D(infinity)(X) = N(1,infinity)(X)

Cortical Injury Increases Cholesterol 24S Hydroxylase (Cyp46) Levels in the Rat Brain

In traumatic brain injury (TBI), cellular loss from initial impact as well as secondary neurodegeneration leads to increased cholesterol and lipid debris at the site of injury. Cholesterol accumulation in the periphery can trigger inflammatory mechanisms while cholesterol clearance may be anti-inflammatory. Here we investigated whether TBI altered the regulation of cholesterol 24S-hydroxylase (Cyp46), an enzyme that converts cholesterol to the more hydrophilic 24S-hydroxycholesterol. We examined by Western blot and immunohistochemistry changes in Cyp46 expression following fluid percussion injury. Under normal conditions, most Cyp46 was present in neurons, with very little measurable in glia. Cyp46 levels were significantly increased at 7 days post-injury, and cell type specific analysis at 3 days post-injury showed a significant increase in levels of Cyp46 (84%) in microglia. Since 24-hydroxycholesterol induces activation of genes through the liver X receptor (LXR), we examined protein levels of ATP-binding cassette transporter A1 and apolipoprotein E, two LXR regulated cholesterol homeostasis proteins. Apolipoprotein E and ATP-binding cassette transporter A1 were increased at 7 days post-injury, indicating that increased LXR activity coincided with increased Cyp46 levels. We found that activation of primary rat microglia by LPS in vitro caused increased Cyp46 levels. These data suggest that increased microglial Cyp46 activity is part of a system for removal of damaged cell membranes post-injury, by conversion of cholesterol to 24-hydroxycholesterol and by activation of LXR-regulated gene transcription

Feasibility and Successful Enrollment in a Proof-of-Concept HIV Prevention Trial of VRC01, a Broadly Neutralizing HIV-1 Monoclonal Antibody

BACKGROUND: The Antibody Mediated Prevention (AMP) trials (HVTN 704/HPTN 085 & HVTN 703/HPTN 081) are the first efficacy trials to evaluate whether VRC01, a broadly neutralizing monoclonal antibody (mAb) targeting the CD4 binding site of the HIV envelope protein, prevents sexual transmission of HIV-1. HVTN 704/HPTN 085 enrolled 2,701 cisgender men and transgender (TG) individuals who have sex with men at 26 sites in Brazil, Peru, Switzerland and the United States. METHODS: Participants were recruited and retained through early, extensive community engagement. Eligible participants were randomized 1:1:1 to 10 mg/kg or 30 mg/kg of VRC01 or saline placebo. Visits occurred monthly, with intravenous (IV) infusions every 8 weeks over 2 years, for a total of ten infusions. Participants were followed for 104 weeks after first infusion. RESULTS: The median HVTN 704/HPTN 085 participant age was 28; 99% were assigned male sex; 90% identified as cisgender male, 5% as TG female and the remaining as other genders. Thirty-two percent were White, 15% Black and 57% Hispanic/Latinx. Twenty-eight percent had a sexually transmitted infection at enrollment. Over 23,000 infusions were administered with no serious IV administration complications. Overall retention and adherence to the study schedule exceeded 90%, and the drop-out rate was below 10% annually (7.3 per 100-person years) through Week 80, the last visit for the primary endpoint. CONCLUSIONS: HVTN 704/HPTN 085 exceeded accrual and retention expectations. With exceptional safety of IV administration and operational feasibility, it paves the way for future large-scale mAb trials for HIV prevention and/or treatment