Minimization of Soil and Nutrient Losses in Maize-Based Cropping Systems in the Mid-Hills of Central Nepal

Soil nutrient depletion is a major concern in terms of resource utilization and optimization of production in the middle hills of Nepal. Soil and nutrient losses from agricultural land is responsible for pollution of surface waters and this reduces the productive capacity of land. A field experiment was initiated in May 2001 on acidic sandy loam soil in Kavre district; Nepal to investigate the efficiency of widely recommended researchable options for soil conservation. The experimental plots were set up as a two factorial design with three main factors (mulching, reduced tillage and conventional farmers' practice as control) and were divided on the basis of cropping patterns (maize sole and maize inter-cropped with soybean). Soil N, P, K, and OM losses were determined from soil eroded in runoff. Nutrient loss in pre- monsoon period (in the month of May) was highly significant among the management practices. Much of nutrient (60 to 90 percent of annual) losses occurred during this period. As compared to conventional farmers' practice, mulching reduced annual soil organic matter loss by 52 percent, annual total nitrogen by 46 percent, annual available P2O5 by 32 percent and annual exchangeable K2O by 53 percent in maize – mustard cropping system. Similarly, in maize + soybean - mustard cropping system, the annual loss of these nutrients were reduced by 58, 49, 26 and 60 percent, respectively. Reduced tillage, on the other hand, produced higher soil loss and hence more nutrient and organic matter loss as compared to mulching practice because of freshly prepared plots and hence less vegetation and more compaction

Sotrovimab versus usual care in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Background: Sotrovimab is a neutralising monoclonal antibody targeting the SARS-CoV-2 spike protein. We aimed to evaluate the efficacy and safety of sotrovimab in the RECOVERY trial, an investigator-initiated, individually randomised, controlled, open-label, adaptive platform trial testing treatments for patients admitted to hospital with COVID-19. Methods: Patients admitted with COVID-19 pneumonia to 107 UK hospitals were randomly assigned (1:1) to either usual care alone or usual care plus a single 1 g infusion of sotrovimab, using web-based unstratified randomisation. Participants were eligible if they were aged at least 18 years, or aged 12–17 years if weighing at least 40kg, and had confirmed COVID-19 pneumonia with no medical history that would put them at significant risk if they participated in the trial. Participants were retrospectively categorised as having a high antigen level if baseline serum SARS-CoV-2 nucleocapsid antigen was above the median concentration (the prespecified primary efficacy population), otherwise they were categorised as having a low antigen level. The primary outcome was 28-day mortality assessed by intention to treat. Safety outcomes were assessed among all participants, regardless of antigen level. Recruitment closed on March 31, 2024, when funding ended. The trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). Findings: From Jan 4, 2022, to March 19, 2024, 1723 patients were enrolled in the RECOVERY sotrovimab comparison. Of these, 828 (48%) were assigned to usual care plus sotrovimab and 895 (52%) were assigned to usual care only. Mean patient age was 70·7 years (SD 14·8) and 1033 (60%) were male. 720 (42%) patients were classified as having a high antigen level, 717 (42%) as having a low antigen level, and 286 (17%) had unknown antigen status. 1389 (81%) patients were vaccinated, 1179 (82%) of 1438 patients with known serostatus had anti-spike antibodies at randomisation, and 1021 (>99%) of 1026 patients with sequenced samples were infected with omicron variants. Among patients with a high antigen level, 82 (23%) of 355 assigned to sotrovimab versus 106 (29%) of 365 assigned usual care died within 28 days (rate ratio 0·75, 95% CI 0·56–0·99; p=0·046). In an analysis of all randomly assigned patients (regardless of antigen status), 177 (21%) of 828 patients assigned to sotrovimab versus 201 (22%) of 895 assigned to usual care died within 28 days (0·95, 0·77–1·16; p=0·60). Infusion reactions were recorded in 12 (2%) of 781 patients receiving sotrovimab. We found no difference between groups in any other safety outcome. Interpretation: In patients admitted to hospital with COVID-19 pneumonia, sotrovimab was associated with reduced mortality in the primary analysis population who had a high serum SARS-CoV-2 antigen concentration at baseline, but not in the overall population. Treatment options for patients admitted to hospital are limited, and mortality in those receiving current standard of care was high. The emergence of high-level resistance to sotrovimab among subsequent SARS-CoV-2 variants restricts its current usefulness, but these results indicate that targeted neutralising antibody therapy could potentially still benefit some patients admitted to hospital who are at high risk of death in an era of widespread vaccination and omicron infection. Funding: UK Research and Innovation (Medical Research Council) and National Institute for Health and Care Research

Effects of riverbed extraction on physico-chemical parameters of Tinau River, Nepal

This study was carried out during June 2010 to March 2011 in the Tinau River, Nepal. The level of pollution was determined based on the protocol of US EPA (Habitat Assessment Protocol). Riverbed extraction was occurring in very large scale in this river since 2002. Five sampling stations were selected to carry out the study. Some specific physico-chemical parameters like Electrical Conductivity (EC), Lead (Pb), pH, Iron (Fe), Phosphorous (P), Ammonia (NH4+), Nitrate (NO3-), Arsenic (As), Total Dissolved Solids (TDS) were analyzed. Three major parameters (Pb, As and TDS) were closely related to the riverbed extraction and exceeded the limit set by WHO for drinking water. Similar relationship was also seen for EC; however its concentrations did not exceed the limit of WHO. The river water was slightly alkaline based on the pH value (ranging from 7.5 to 9).Other parameters did not seem to be related to the riverbed extraction. However, the nitrate and phosphorous concentrations were also high during the present investigation. Lack of similar studies prevented us to compare the result; however these findings provide the baseline data for future work

Surface crusting as a constraint to sustainable management on a tropical alfisol: II. Strength characteristics during crust development

Crust strength impacts agronomic production through its effect on tillage and planting, seedling emergence and establishment, as well as, runoff and erosion. Therefore, a field experiment was conducted at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), India, to evaluate surface crust strength characteristics under six cropping and management systems. Penetration resistance (PR) and shear strength (VS) of surface soil was 50 to 300% higher prior to tillage, under dry and crusted conditions than at 21 and 60 days after tillage (DAT). Cohesion and unconfined compressive strength (UCS) followed similar trends to those of PR and VS with 30 to 65% higher values by 109 DAT compared to 0 and 50 DAT. These results reflected the effect of moisture content as welt as crust development from compaction and consolidation of the surface (5–10 mm) soil layer. During the post-harvest period PR, VS and needle penetration resistance (NPR) exhibited sharp increases at soil moisture contents less than about 0.10gg−1, suggesting possible hardsetting tendency of the soil. Highest NPR (ranging from 1.6–7.2 MPa) occurred at 78 and 156 DAT when visible crusting was apparent. Lower NPR at 156 DAT than at 78 DAT for some treatments was attributed to soil surface micro-variability due to crust cracking, soil faunal activity and excessive drying. Adequate soil cover from crop residue or deep-rooted, prolific perennials such as Cenchrus and Stylosanthes may effectively reduce and ameliorate surface crusting on Alfisols in the semi-arid tropics