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Author(s): Rohit Singh Chauhan (corresponding author) [1]; Anusheel Munshi [2]; Anirudh Pradhan [3] INTRODUCTION The growing global burden of cancer has become a major concern, with projections indicating a 47% [...], Aim: This article examines India's present radiotherapy (RT) machine status and requirements, geographical distribution, and infrastructure need in six regional areas, which include 31 member states and union territories (UTs). It also considers the influence of the COVID-19 pandemic on India's teletherapy sector. Materials and Methods: Data from reliable resources, including Atomic Energy Regulatory Board, Global Cancer Observatory, and Directory of Radiotherapy Centres databases, were used to analyze the current status of RT machine (RTM) density, regional disparity, and COVID-19 impact on infrastructure growth-rate. Results: In India, the number of functioning RTM and facilities are 823 and 554, respectively, with an average of 1.5 RTM per institute, of which 69.4% have only one RTM. Over the past 22 years, there has been a paradigm shift towards medical linear accelerator (linac) installation instead of telecobalt machines. Presently, there is a teletherapy density of 0.6 RTM per million population, and there is a shortfall of 1209 RTMs. There is a considerable regional disparity in the distribution of RTMs, ranging from (0.08 RTM/million-2.94 RTM/million) across different regions. There is a significant demand for RTMs in the Northern region (480) and the state of Uttar Pradesh (279). The COVID-19 pandemic temporarily impacted India's RT growth rate, reducing it from 5% to 1.9% in 2020-2021. Conclusions: New policies must be established to accelerate the rate of RT installation growth. To better serve local populations and save patient costs, this article proposes that RT facilities be dispersed equitably across states. Keywords: COVID-19, health policy, oncology, particle accelerators, radiotherapy

In this article, the manuscript of Codex Madrid I, Leonardo da Vinci's workshop drawings collection, is reviewed and the main mechanisms that appear in the aforesaid codex are analysed. It begins with a short reference to Leonardo da Vinci works and, subsequently, Leonardo's manuscripts and Codex Madrid I, in particular, are placed in their historical context. After analysing the historical scope of Codex Madrid I, a compilation of the 100 main drawings of the manuscript is made, composing nine Mechanisms Drawings Boxes. Each Mechanisms Drawings Box is a collage made up of 10 to 14 drawings of mechanical elements that appear in Codex Madrid I, with a brief description of each drawing. This compilation illustrates the wide range of mechanical elements and simple mechanisms of Codex Madrid I, forming, as a whole, a complete treatise on mechanisms, understanding mechanisms as basic elements of machines., Author(s): H. Rubio [sup.1], A. Bustos [sup.1], C. Castejon [sup.1], J. Meneses [sup.1] Author Affiliations: (1) https://ror.org/03ths8210, grid.7840.b, 0000 0001 2168 9183, University of Carlos III of Madrid, , Leganés [...]

Forestry-drained peatlands occupy approximately 15 million ha in boreal and temperate zones. In Finland, they represent almost one-fourth of the total forest area. They are subjected to the same harvesting operations as upland forests. Although the soil deformation caused by timber harvesting is well documented in upland forests, the knowledge on the soil disturbance induced by the harvesting machinery on peat soils is still lacking. To address this, we collected soil samples from six peatland sites that were thinned using a harvester-forwarder combination. Peat samples were taken from the trails formed by the machinery and outside the trails to a depth of 10 cm. To assess the recovery of soil properties after the disturbance, we sampled sites along a chronosequence with respect to time since harvesting. Soil deformation under the machinery appeared to increase the bulk density and field capacity of peat and decrease its total porosity; however, disturbed plots and control plots started to resemble each other in their soil properties within 15 years. The results imply that peat soil is sensitive to disturbance but has a high recovery potential. Key words: drained peatlands, forest harvesting, bulk density, water retention, pore size distribution. Les tourbieres drainees pour l'exploitation forestiere occupent environ 15 millions d'hectares en regions boreale et temperee. En Finlande, elles representent presque 25 % de la superficie forestiere totale. Elles sont soumises aux memes operations forestieres que les forets en milieu sec. Bien que la deformation du sol causee par l'exploitation forestiere soit bien documentee dans les forets en milieu sec, les connaissances sur la perturbation du sol causee par la machinerie forestiere sur les sols tourbeux sont encore deficientes. Pour aborder cette question, nous avons collecte des echantillons de sol dans six tourbieres eclaircies en utilisant une combinaison d'abatteuse et porteur. Des echantillons de tourbe ont ete preleves dans les sentiers crees par la machinerie et a l'exterieur des sentiers jusqu'a une profondeur de 10 cm. Pour evaluer la recuperation des proprietes du sol a la suite de la perturbation, nous avons echantillonne des stations le long d'une chronosequence representant le temps ecoule depuis la recolte. La deformation du sol sous la machinerie semblait augmenter la masse volumique apparente et la capacite au champ de la tourbe et diminuer sa porosite totale. Cependant, les proprietes du sol des parcelles perturbees et temoins ont commence a se ressembler apres moins de 15 ans. Les resultats indiquent que les sols tourbeux sont sensibles aux perturbations mais qu'ils ont un potentiel de recuperation eleve. [Traduit par la Redaction] Mots-cles: tourbieres drainees, exploitation forestiere, masse volumique apparente, retention d'eau, distribution de la dimension des pores., 1. Introduction Sustainable forest management aims at the utilization of forests in a way that maintains and enhances the long-term health and productivity of the forest ecosystem (Schanz 2004). Soil [...]

Some topsoil physical properties evolve unfavourably under continuous, no-till fanning. On the Pampa, loam soils under no-till sometimes have lower infiltration rates than those conventionally tilled; this is due to the occurrence of platy and massive structures. In this study, we aimed to identify the soil management practices that promote platy structure formation, and explain the soil physical behaviour linked to the thickness of platy structures in relation to infiltration rate, bulk density and shear strength. Six fields with different numbers of years under agriculture and diverse previous crops (maize or wheat-soybean double crop) were sampled, distinguishing within each field headlands (areas with higher traffic) and centre (lower traffic). Twenty samples were taken at random along a 200-m transect to characterise soil structure (platy, granular or massive) and the thickness of the platy structure. Principal component analysis revealed linkages between previous crop and location in each field and type of structure. ANOVA showed a significant (Pc 0.05) interaction of previous crop x location. The frequency and thickness of the platy structures were lower, and those of granular structures higher, under wheat--soybean double cropping and in the centre of the field. Greater thickness of the platy structure determined lower water infiltration rate (r=-0.337; P Additional keywords: infiltration rate, machinery traffic, no-till, shear strength, structural types., Introduction Physical properties are an important part of the evaluation of soil quality and health (Hussain et al. 1999). Soil structure is generally characterised by form, stability and resilience. Structural [...]

Intermeshing counter-rotating twin screw extruders play an important role in polymer processing, especially for the extrusion of profiles and pipe, largely from polyvinyl chloride. There has been little effort on flow modeling of these machines and most of this has involved representing the machine as a 'leaky' positive displacement pump and estimating leakages. In recent years, M.H. Hong and the authors have developed more general methods of simulation of flow in this machine and both applied and experimentally verified it for a few designs. Here we extend these efforts to a broader range of screw designs, especially with deeper screw channels where transverse shearing induced by the flights is important. Calculations are done for isothermal power law fluids. The results are compared with experiment. POLYM. ENG. SCI., 51:37-42, 2011. [C]2010 Society of Plastics Engineers, INTRODUCTION The flow of polymer melts in intermeshing counter-rotating twin screw extruder (Fig. 1) has been subjected to only limited study. The machine seems first described in the 19th century [...]