Estudio de la adptabilidad de dos cultivares de Remolacha azucarera (Beta vulgaris L.) a la puna; Caserío de Huaynas; bajo tres dosis nitrogenadas

La presente investigación se realizó en el caserío de Huaynas, distrito de Huaso, provincia de Julcán, en el departamento de La Libertad, en la zona ecológica Pradera Muy Húmeda Montano, a una elevación de 3887 msnm, durante los meses de enero a setiembre del año 2015. Se trabajó con dos cultivares monogermen de remolacha azucarera: SVPE 14-02 y SVPE 14- 03. Los objetivos del presente estudio fueron: a) determinar la adaptabilidad de los cultivares SVPE 14-02 y SVPE 14-03 a las condiciones climatológicas de la puna; b) determinar el efecto de la fertilización nitrogenada en la producción de los cultivares de remolacha azucarera; c) determinar cuál de los cultivares estudiados produce mayores rendimientos. Para lograr estos objetivos, se instalaron dos experimentos (uno por cultivar) con una densidad de siembra de 150 000 plantas por hectárea, con tres dosis nitrogenadas: 0 kgN.ha-1 , 100 kgN.ha-1 y 200 kgN.ha-1 . Se encontró que los cultivares SVPE 14-02 y SVPE 14-03 se adaptan a la zona ecológica Pradera Muy Húmeda Montano; resistiendo muy bien las heladas pero no los prolongados periodos de sequía en la etapa inicial del ciclo vegetativo. Bajo las condiciones climatológicas de la puna, y de sequía extrema, el cultivar SVPE 14-02 produjo mayores rendimientos (en promedio 0.62 t.ha-1 , con un máximo de 1.6 t.ha-1 ) a los obtenidos por el cultivar SVPE 14-03 (en promedio 0.2 t.ha-1 ), en el tratamiento N2 con 100 kgN.ha-1 . El estrés hídrico, para ambos cultivares estudiados, fue el factor limitante para el normal desarrollo de las plantas de remolacha azucarera, y consecuentemente, para la obtención de altos rendimientos del cultivo por hectárea.This research was conducted in Huaynas village, Huaso district, Julcán province, in La Libertad department, in the ecological zone “Praire Very Humid Montane” at an elevation of 3887 meters above sea level during the months of January to September of 2015. Two monogerm sugar beet cultivars were used: SVPE 14-02 and SVPE 14-03. The objectives of this study were: a) determine the suitability of cultivars SVPE 14-02 and SVPE 14-03 to puna’s weather conditions; b) determine the effect of nitrogen fertilization in the production of sugar beet cultivars; c) determine which of the studied cultivars produce higher yields. To achieve these objectives, two experiments were installed (one per cultivar) with a seeding density of 150 000 plants per hectare, with three nitrogen doses: 0 kgN.ha-1 , 100 kgN.ha-1 and 200 kgN.ha-1 . It was found that cultivars SVPE 14-02 and SVPE 14-03 do adapt well to the ecological zone “Praire Very Humid Montane”; resisting frost well but not prolonged periods of drought in the initial stage of the vegetative cycle. Under puna’s weather conditions, and extreme drought, cultivar SVPE 14- 02 produced higher yields (on average 0.62 t.ha-1 , with a maximum of 1.6 t.ha-1 ) than those obtained by cultivar SVPE 14-03 (on average 0.2 t.ha-1 ), in the treatment N2 with 100 kgN.ha-1 . Water stress in both studied cultivars was limiting for the normal development of sugar beet plants and, consequently, for obtaining higher crop yields per hectare.Tesi

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection