Perbanyakan Mikro Colocasia Esculenta (L.) Schott Var. Antiquorum melalui Penggunaan IAA

Media perbanyakan in vitrosangat diperlukan untuk meningkatkan kemampuan multipikasi tunas maupun kualitas bibit. Media Murashige Shoog (MS)dapatditambahkanzat pengatur tumbuh sebagai pemacu pertumbuhan dalam kultur in vitro.Penelitian ini bertujuan untuk mendapatkan konsentrasi IAA terbaik bagi pertumbuhan talas jepang dalam kulturin vitro. Perlakuan terdiri dari 4 taraf konsentrasi IAA yaitu I0 (0 mg/L), I1 (0,5 mg/L), I2 (1 mg/L), I3 (1,5 mg/L) yang diulang sebanyak 5 kali dalam rancangan acak kelompok. Hasil penelitian ini menunjukan bahwa pemberian IAA berpengaruh nyata terhadap saat muncul tunas, jumlah tunas, tinggi tunas, jumlah daun dan jumlah akar satoimo. Konsentrasi IAA 0,5 mg/L merupakan konsentrasi terbaik untuk pertumbuhan akar dan saat muncul tunas talas satoimo, sedangkan konsentrasi IAA 1 mg/L merupakan konsentrasi terbaik untuk jumlah tunas, tinggi tunas dan jumlah daun satoimo. Kata kunci: kultur in vitro, talas jepang, IAA, perbanyaka

A collaborative and evolving response to the needs of frontline workers, patients and families during the COVID-19 pandemic at Tygerberg Hospital, Western Cape Province, South Africa

The global devastation caused by the COVID-19 pandemic and its mental health impact is undeniable. The physical and psychological consequences are wide-ranging – affecting patients fighting the disease, frontline workers in the trenches with them, healthcare staff deployed in high-care settings, and families disconnected from their loved ones in their darkest hours. Within 6 weeks of the COVID-19 outbreak in South Africa, the Department of Psychiatry at Stellenbosch University established the TBH/SU COVID Resiliency Clinic to provide psychological support to frontline workers at Tygerberg Hospital. Identified barriers in healthcare workers accessing mental healthcare resulted in moving towards an on-site visibility to try to remove some of these barriers. This greater on-site presence enabled networking and building of relationships with frontline staff that over time highlighted other frontline needs, such as providing psychosocial and spiritual support to patients and their families. We share challenges, lessons learned and recommendations from two initiatives: the TBH/SU COVID-19 Resiliency Clinic, and an embedded COVID Care Team (CCT). We describe the establishment, roll-out and progress of the Clinic and the subsequent CCT

The A-ring reduction of 11-ketotestosterone is efficiently catalysed by AKR1D1 and SRD5A2 but not SRD5A1

Testosterone and its 5α-reduced form, 5α-dihydrotestosterone, were previously thought to represent the only active androgens in humans. However, recent studies have shown that the potent androgen, 11-ketotestosterone, derived from the adrenal androgen precursor, 11β-hydroxyandrostenedione, may in fact serve as the primary androgen in healthy women. Yet, despite recent renewed interest in these steroids, their downstream metabolism has remained undetermined. We therefore set out to investigate the metabolism of 11-ketotestosterone by characterising the 5α- or 5β-reduction commitment step. We show that inactivation of 11-ketotestosterone is predominantly driven by AKR1D1, which efficiently catalyses the 5β-reduction of 11-ketotestosterone, committing it to a metabolic pathway that terminates in 11-ketoetiocholanolone. We demonstrate that 5α-reduction of 11-ketotestosterone is catalysed by SRD5A2, but not SRD5A1, and terminates in 11-ketoandrosterone, but is only responsible for a minority of 11-ketotestosterone inactivation. However, as 11-ketoetiocholanolone is also generated by the metabolism of the glucocorticoid cortisone, 11-ketoandrosterone should be considered a more specific urinary marker of 11-ketotestosterone production

Shallow rainwater lenses in deltaic areas with saline seepage

In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and size. Our findings are based on different types of field measurements and detailed numerical groundwater models applied in the south-western delta of the Netherlands. By combining the applied techniques we could extrapolate measurements at point scale (groundwater sampling, temperature and electrical soil conductivity (TEC)-probe measurements, electrical cone penetration tests (ECPT)) to field scale (continuous vertical electrical soundings (CVES), electromagnetic survey with EM31), and even to regional scale using helicopter-borne electromagnetic measurements (HEM). The measurements show a gradual mixing zone between infiltrating fresh rainwater and upward flowing saline groundwater. The mixing zone is best characterized by the depth of the centre of the mixing zone <i>D</i><sub>mix</sub>, where the salinity is half that of seepage water, and the bottom of the mixing zone <i>B</i><sub>mix</sub>, with a salinity equal to that of the seepage water (Cl-conc. 10 to 16 g l<sup>−1</sup>). <i>D</i><sub>mix</sub> is found at very shallow depth in the confining top layer, on average at 1.7 m below ground level (b.g.l.), while <i>B</i><sub>mix</sub> lies about 2.5 m b.g.l. The model results show that the constantly alternating upward and downward flow at low velocities in the confining layer is the main mechanism of mixing between rainwater and saline seepage and determines the position and extent of the mixing zone (<i>D</i><sub>mix</sub> and <i>B</i><sub>mix</sub>). Recharge, seepage flux, and drainage depth are the controlling factors

Knee movement patterns of injured and uninjured adolescent basketball players when landing from a jump: A case-control study

BACKGROUND: A common knee injury mechanism sustained during basketball is landing badly from a jump. Landing is a complex task and requires good coordination, dynamic muscle control and flexibility. For adolescents whose coordination and motor control has not fully matured, landing badly from a jump can present a significant risk for injury. There is currently limited biomechanical information regarding the lower limb kinetics of adolescents when jumping, specifically regarding jump kinematics comparing injured with uninjured adolescents. This study reports on an investigation of biomechanical differences in landing patterns of uninjured and injured adolescent basketball players. METHODS: A matched case-control study design was employed. Twenty-two basketball players aged 14–16 years participated in the study: eleven previously knee-injured and eleven uninjured players matched with cases for age, gender, weight, height and years of play, and playing for the same club. Six high-speed, three-dimensional Vicon 370 cameras (120 Hz), Vicon biomechanical software and SAS Version 8 software were employed to analyse landing patterns when subjects performed a "jump shot". Linear correlations determined functional relationships between the biomechanical performance of lower limb joints, and paired t-tests determined differences between the normalised peak biomechanical parameters. RESULTS: The average peak vertical ground reaction forces between the cases and controls were similar. The average peak ground reaction forces between the cases and controls were moderately correlated (r = -0.47). The control (uninjured) players had significantly greater hip and knee flexion angles and significantly greater eccentric activity on landing than the uninjured cases (p < 0.01). CONCLUSION: The findings of the study indicate that players with a history of knee injuries had biomechanically compromised landing techniques when compared with uninjured players matched for gender, age and club. Descriptions (norms) of expected levels of knee control, proprioceptive acuity and eccentric strength relative to landing from a jump, at different ages and physical developmental stages, would assist clinicians and coaches to identify players with inappropriate knee performance comparable to their age or developmental stage

High HIV prevalence in an early cohort of hospital admissions with COVID-19 in Cape Town, South Africa

Background. South Africa (SA) has a high prevalence of HIV and tuberculosis. Cape Town was the SA metropole most affected in the early stages of the COVID-19 pandemic. Early observational data from Africa may provide valuable insight into what can be expected as the pandemic expands across the continent.Objectives. To describe the prevalence, clinical features, comorbidities and outcome of an early cohort of HIV-positive and HIV-negative patients admitted with COVID-19.Methods. This was a descriptive observational study of an early cohort of adults with COVID-19 pneumonia admitted from 25 March to 11 May 2020.Results. Of 116 patients (mean age 48 years, 61% female) admitted, 24 were HIV-positive (21%). The most common symptoms reported were cough (n=88; 73%), shortness of breath (n=78; 69%), fever (n=67; 59%), myalgia (n=29; 25%) and chest pain (n=22; 20%). The most common comorbidities were hypertension (n=46; 41%), diabetes mellitus (n=43; 38%), obesity (n=32; 28%) and HIV (n=24; 21%). Mortality was associated with older age (mean (standard deviation) 55 (12) years v. 46 (14) years; p&lt;0.01); the presence of hypertension or hypertension along with diabetes and/or obesity; lower partial pressure of arterial oxygen to fraction of inspired oxygen ratio; and higher urea level, white cell count, neutrophil count, and C-reactive protein, lactate dehydrogenase and ferritin levels, and high neutrophil to lymphocyte ratio. The overall survival rate for all hospital admissions was 86/116 (73%). In this early cohort, survival was similar in patients with HIV (n=18; 75%) compared with those without HIV (n=67; 75%) (p=1). Of the 74 patients admitted to the wards, 63 (85%) survived, whereas 22 of 42 (52%) admitted to the intensive care unit survived.Conclusions. Patients with HIV infection represented a large proportion of all COVID-19 admissions. The presentation and outcome of patients with HIV did not differ significantly from those of patients without HIV

Fly-by-Pi: open source closed-loop control for geotechnical centrifuge testing applications

Geotechnical centrifuges are valuable instruments for physical modelling of complex geotechnical problems in a controlled laboratory setting. In comparison to full-scale testing, scaled models are cost effective to construct and instrument and, when tested in a geotechnical centrifuge at increased centrifugal accelerations, are capable of replicating full-scale stress–strain soil behaviour. Centrifuge modellers require specialised hardware and instruments capable of functioning under high accelerations. Such hardware is costly, nearly always purpose built, and often rely on commercial, closed-source data acquisition systems, hardware and control systems. This paper demonstrates a novel and versatile, low cost, open source logger and control system that works in parallel alongside existing centrifuge hardware. This solution, termed Fly-by-Pi, was developed using the Raspberry Pi microcomputer. The system provides closed-loop control of linear actuators with the ability to operate in either cyclic, monotonic, or static load- or displacement-control. The control mechanism can be reprogrammed according to experimental requirements, even during flight in the centrifuge. Three independent experiments are described which included the Fly-by-Pi controller as a key component in their operation. Based on the experience gained during these experiments, the authors encourage wide-spread adoption of open-sourced hardware solutions in extreme testing environments

Shaping public Opinion for confrontation : catalan independence claims as represented in spanish, catalan, valencian, and basque editorials

Editorials represent a newspaper's principal means of ideological positioning and serve to identify the attitude of each newspaper and its readership to some of the main actors in any given conflict, especially those that are political in nature. Catalonia's independence movement has experienced a surge in recent years. The turning point came in July 2010, after Spain's constitutional court ruled against some aspects of Catalonia's Statute of Autonomy (the legislation regulating the relationship between the Catalan autonomous community and the Spanish state). The ruling annulled some of the articles of the statute. The demonstration in support of Catalan independence that took place on September 11, 2012, was considered the most important among several mass rallies held for this purpose over successive years on Catalonia's National Day. This article presents the results of a qualitative and quantitative analysis of editorial articles published around these two key dates, with the goal of studying each newspaper's treatment of political actors and their degree of identification with these actors. Their use of arguments aimed at persuading readers and legitimizing a given position during the specified time periods in 2010 and 2012 will also be studied. The study focuses on the editorial articles published by several newspapers in four distinct regional contexts: Catalonia, Valencia, the Basque Country, as well as the whole of Spain. The analyzed articles were published a few days before and after July 10, 2010, and September 11, 2012