Subsoiling an irrigated and dryland Brown Chernozem: effects on soil density, moisture, yield, and economic return

Non-Peer ReviewedThere has been a renewed interest in subsoiling among agricultural producers in Saskatchewan, looking to improve soil water management and crop yield. Subsoiling in this study was performed using a Paraplow (Howard Rotavator). Evaluating the tillage effects of subsoiling, looking at changes to bulk density and moisture, and crop yield. Paraplowing reduced bulk density and its effects persisting over multiple field seasons. The changes to the soil physical properties also had an affect on crop production, observing variations in grain yield in the dryland cropping system, but no measurable effect in irrigated systems. It is important to also consider if the operation is economical. Without a multi-year yield benefit it is difficult recover the costs of the operation

Soil nitrate and crop yield in response to subsoil loosening by paraplow

Non-Peer Reviewe

Effects of paratilling on soil bulk density and infiltration

Non-Peer ReviewedParatilling is a form of non-inversion deep tillage sought after by producers for its effectiveness at loosening soil structure without compromising the soil conservation practices that are already employed on the farm. An experiment was set up to evaluate the tillage effects of paratilling. Looking at changes to the soil physical properties, bulk density and infiltration, and crop yield. Initially, paraplowing reduced bulk density and soil strength but with over time these effects were eroded. At the Vertisolic site the effects were lost before the end of the first growing season, which may be a result of natural processes and the unusually wet spring. Infiltration increased as a result of paratilling. Soil loosening did not increase yield suggesting that soil structure is not limiting plant growth at these sites. Paratilling is only feasible if a yield response is observed

What is the Entanglement Length in a Polymer Melt ?

We present results of molecular dynamics simulations of very long model polymer chains analyzed by various experimentally relevant techniques. The segment motion of the chains is found to be in very good agreement with the repatation model. We also calculated the plateau-modulus G_N. The predicitions of the entanglement length N_e from G_N and from the mean square displacements of the chains segments disagree by a factor of about 2.2(2), indicating an error in the prefactor in the standard formula for G_N. We show that recent neutron spin echo measurements were carried out for chain lengths which are too small for a correct determination of N_e.Comment: 5 pages, 4 figures, RevTe

Effect of subsoiling on strength of a Chernozemic soil

Non-Peer Reviewe

Post-acute COVID-19 neuropsychiatric symptoms are not associated with ongoing nervous system injury

A proportion of patients infected with severe acute respiratory syndrome coronavirus 2 experience a range of neuropsychiatric symptoms months after infection, including cognitive deficits, depression and anxiety. The mechanisms underpinning such symptoms remain elusive. Recent research has demonstrated that nervous system injury can occur during COVID-19. Whether ongoing neural injury in the months after COVID-19 accounts for the ongoing or emergent neuropsychiatric symptoms is unclear. Within a large prospective cohort study of adult survivors who were hospitalized for severe acute respiratory syndrome coronavirus 2 infection, we analysed plasma markers of nervous system injury and astrocytic activation, measured 6 months post-infection: neurofilament light, glial fibrillary acidic protein and total tau protein. We assessed whether these markers were associated with the severity of the acute COVID-19 illness and with post-acute neuropsychiatric symptoms (as measured by the Patient Health Questionnaire for depression, the General Anxiety Disorder assessment for anxiety, the Montreal Cognitive Assessment for objective cognitive deficit and the cognitive items of the Patient Symptom Questionnaire for subjective cognitive deficit) at 6 months and 1 year post-hospital discharge from COVID-19. No robust associations were found between markers of nervous system injury and severity of acute COVID-19 (except for an association of small effect size between duration of admission and neurofilament light) nor with post-acute neuropsychiatric symptoms. These results suggest that ongoing neuropsychiatric symptoms are not due to ongoing neural injury.</p