scholarly journals Mechanical behavior of pumpkin fruits subjected to compression during maturation

2013 ◽  
Vol 43 (3) ◽  
pp. 223-231 ◽  
Author(s):  
Acácio Figueiredo Neto ◽  
Francisco de Assis Cardoso Almeida ◽  
Nelson Cárdenas Olivier ◽  
Alan Christie Silva Dantas ◽  
Marcos Antonio Silva Irmão

During handling operations, many problems that reduce the quality of vegetables may occur. Mechanical injuries are the leading cause of postharvest losses for the pumpkin, and can take place at any point of the production chain. This study aimed at evaluating the pumpkin fruits behavior, during their ripening stages, on the values of maximum compression force for fixed deformations, and determining the proportional deformability modulus of the fruits under compression at the repose position. Fruits were harvested at 15, 30, 40, 50 and 60 days after flowering and uniaxially compressed between two parallel plates. The results allowed to conclude that both the required compression force and the proportional deformability modulus increased during the maturation course, reaching a maximum force of 1,778 N and a maximum deformation modulus of 164 MPa, after 30 days. After this period, both the maximum force and the modulus values decreased, reaching 1,514.8 N of maximum force and a modulus of 132.09 MPa, after 60 days of ripening. Over the course of a longer maturation time, the fruit firmness increased, therefore requiring an increase in the maximum load to achieve greater deformation. The ideal period for harvest and transport of 'Jacarezinho' pumpkin fruits was set from 30 to 40 days after anthesis.

2019 ◽  
Vol 11 (4) ◽  
pp. 279
Author(s):  
Gabrielly B. Rodrigues ◽  
Osvaldo Resende ◽  
Daniel E. C. de Oliveira ◽  
Lígia C. de M. Silva ◽  
Weder N. Ferreira Junior

This study aimed to evaluate the influence of drying at different temperatures on the mechanical properties of grains of grain sorghum subjected to compression at the natural rest position. Grains dried at temperatures of 60, 80 and 100 °C with different moisture contents (0.515; 0.408; 0.315; 0.234; 0.162 and 0.099 (d.b.)) were subjected to uniaxial compression between two parallel plates, applied at their natural rest position, at a rate of 0.001 m s-1. The force required to rupture in grains of grain sorghum increased as their moisture contents decreased, with values of 47.17 to 78.44 N, 61.81 to 69.66 N and 52.07 to 70.89 N for the temperatures of 60, 80 and 100 °C, respectively. The compression force required to deform grain sorghum decreased with the increment in moisture content, and the proportional deformation modulus increases with moisture content reduction. Within the studied range of moisture content, the values were 87 × 10-7 to 354.99 × 10-7 Pa, 132.63 × 10-7 to 465.98 × 10-7 Pa and 80.18 × 10-7 to 429.85 × 10-7 Pa for the temperatures of 60, 80 and 100 °C, respectively.


2017 ◽  
Vol 1 (2) ◽  
Author(s):  
Leonor Alexandra Rodríguez Álava

Este artículo está encaminado a caracterizar el proceso de formación continua del docente del nivel medio en ejercicio asociado a la formación y desarrollo de sus competencias docentes, para lo que fueron utilizados métodos como   el análisis y síntesis, inducción y deducción, abstracción y concreción, la entrevista, la encuesta y  el cuestionario, donde a partir de sus resultados se  llega a la consideración de que la formación continua es la vía idónea para la formación y desarrollo de competencias docentes en los profesores en ejercicio, donde se debe asumir un modelo que propicie la reflexión sobre la propia práctica del docente, un clima de colaboración   y el profesor como sujeto activo de ese proceso.   Palabras claves: calidad educativa,   competencias docentes,   educador, estudio, preparación continua,  ABSTRACT   This article aims to characterize the process of education for teachers of middle level associated with exercise training and development of their teaching skills, for which methods were used as analysis and synthesis, induction and deduction, abstraction and concreteness, interview and questionnaire survey, where from their results leads to the consideration that the training is the ideal way for the formation and development of teaching skills in practicing teachers, where they must assume a model that encourages reflection on own teaching practice, a climate of collaboration and the teacher as an active subject of that process Keywords: quality of education, teaching skills, teacher, study, continuous preparation


Author(s):  
Joseph Winters

This chapter engages humanism and its fundamental assumptions by working through critical theory, black feminism, and black studies. It contends that there is a tension at the heart of humanism—while the ideal human appears to be the most widespread and available category, it has been constructed over and against certain qualities, beings, and threats. To elaborate on this tension, this chapter revisits the work of authors like Karl Marx and Michel Foucault. Marx acknowledges that the human is a site of conflict and antagonism even as his thought betrays a lingering commitment to progress and humanism. Foucault goes further than Marx by underscoring the fabricated quality of man and the ways in which racism functions to draw lines between those who must live and those who must die. In response to Marx and Foucault’s tendency to privilege Europe, this chapter engages black feminism and Afro-pessimism—Sylvia Wynter, Hortense Spillers, and Frank Wilderson—who show how the figure of the human within humanism is defined in opposition to blackness.


Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 929
Author(s):  
Hanadi Sawalha ◽  
Rambod Abiri ◽  
Ruzana Sanusi ◽  
Noor Azmi Shaharuddin ◽  
Aida Atiqah Mohd Noor ◽  
...  

Nanotechnology is a promising tool that has opened the doors of improvement to the quality of human’s lives through its potential in numerous technological aspects. Green chemistry of nanoscale materials (1–100 nm) is as an effective and sustainable strategy to manufacture homogeneous nanoparticles (NPs) with unique properties, thus making the synthesis of green NPs, especially metal nanoparticles (MNPs), the scientist’s core theme. Researchers have tested different organisms to manufacture MNPs and the results of experiments confirmed that plants tend to be the ideal candidate amongst all entities and are suitable to synthesize a wide variety of MNPs. Natural and cultivated Eucalyptus forests are among woody plants used for landscape beautification and as forest products. The present review has been written to reflect the efficacious role of Eucalyptus in the synthesis of MNPs. To better understand this, the route of extracting MNPs from plants, in general, and Eucalyptus, in particular, are discussed. Furthermore, the crucial factors influencing the process of MNP synthesis from Eucalyptus as well as their characterization and recent applications are highlighted. Information gathered in this review is useful to build a basis for new prospective research ideas on how to exploit this woody species in the production of MNPs. Nevertheless, there is a necessity to feed the scientific field with further investigations on wider applications of Eucalyptus-derived MNPs.


Author(s):  
Chiwon Ahn ◽  
Seungjae Lee ◽  
Jongshill Lee ◽  
Jaehoon Oh ◽  
Yeongtak Song ◽  
...  

This study aimed to assess the effectiveness of a novel chest compression (CC) smart-ring-based feedback system in a manikin simulation. In this randomized, crossover, controlled study, we evaluated the effect of smart-ring CC feedback on cardiopulmonary resuscitation (CPR). The learnability and usability of the tool were evaluated with the System Usability Scale (SUS). Participants were divided into two groups and each performed CCs with and without feedback 2 weeks apart, using different orders. The primary outcome was compression depth; the proportion of accurate-depth (5–6 cm) CCs, CC rate, and the proportion of complete CCs (≤1 cm of residual leaning) were assessed additionally. The feedback group and the non-feedback group showed significant differences in compression depth (52.1 (46.3–54.8) vs. 47.1 (40.5–49.9) mm, p = 0.021). The proportion of accurate-depth CCs was significantly higher in the interventional than in the control condition (88.7 (30.0–99.1) vs. 22.6 (0.0–58.5%), p = 0.033). The mean SUS score was 83.9 ± 8.7 points. The acceptability ranges were ‘acceptable’, and the adjective rating was ‘excellent’. CCs with smart-ring feedback could help achieve the ideal range of depth during CPR. The smart-ring may be a valuable source of CPR feedback.


2020 ◽  
pp. 073346482096261
Author(s):  
Carol Opdebeeck ◽  
Michael A. Katsaris ◽  
Anthony Martyr ◽  
Ruth A. Lamont ◽  
James A. Pickett ◽  
...  

Pet ownership has been associated with positive outcomes in many populations, yet the associations with physical and psychological wellbeing in people with dementia remain unclear. The current study used baseline data from 1,542 people living at home with mild-to-moderate dementia from the Improving the experience of Dementia and Enhancing Active Life (IDEAL) programme. Regression analyses investigated associations of pet ownership and pet care with self-reports of walking, loneliness, depression, and quality of life (QoL). After adjusting for covariates, having any pet was associated with higher likelihood of walking over 3 hr in the last week. Those with a dog and who were involved in its care were less likely to be lonely than those with no dog. Having any pet but no involvement in its care was associated with increased depression and decreased QoL compared with those without a pet. The key factor in the associations was involvement in the care of the pet by the person with dementia.


2021 ◽  
Vol 3/2021 (2) ◽  
pp. 41-50
Author(s):  
Lucia Ludvigh Cintulová ◽  
Libuša Radková

This article presents an investigation into how primary-school pupils imagine a good teacher and what characteristics of teachers they appreciate. The teacher’s personality is a quality of central importance to the teaching process. Teachers find themselves in many diverse situations and they cannot always remain the same. Each situation requires different qualities, attitudes and knowledge. In different situations, the teacher can achieve the same educational outcome in various ways, by using a range of methods. No teacher can be expected to have the ideal personality and cannot possibly have all the desired qualities, so some qualities compensate for the lack of others. However, the crucial aspects of a good teacher’s personality is authenticity, naturalness and positive relationship with pupils.


2022 ◽  
Vol 12 (2) ◽  
pp. 411-416
Author(s):  
Liang Tang ◽  
Si-Yu Zhao ◽  
Ya-Dong Yang ◽  
Geng Yang ◽  
Wen-Yuan Zhang ◽  
...  

To investigate the degradation, mechanical properties, and histocompatibility of weft-knitted silk mesh-like grafts, we carried out the In Vitro and In Vivo silk grafts degradation assay. The In Vitro degradation experiment was performed by immersing the silk grafts in simulated body fluid for 1 year, and the results showed that the degradation rate of the silk mesh-like grafts was very slow, and there were few changes in the mechanical properties and quality of the silk mesh-like graft. In Vivo degradation assay was taken by implantation of the silk mesh-like grafts into the subcutaneous muscles of rabbits. At 3, 6, and 12 months postoperation, the rate of mass loss was 19.36%, 31.84%, and 58.77%, respectively, and the maximum load was 63.85%, 34.63%, and 10.76%, respectively of that prior to degradation. The results showed that the degradation rate of the silk graft and the loss of mechanical properties In Vivo were faster than the results obtained in the In Vitro experiments. In addition, there were no significant differences in secretion of serum IL-6 and TNF-α between the experimental and normal rabbits (P >0.05), suggesting no obvious inflammatory reaction. The findings suggest that the weft-knitted silk mesh-like grafts have good mechanical properties, histocompatibility, and In Vivo degradation rate, and therefore represent a candidate material for artificial ligament


Author(s):  
Gerry Mackie

Deliberative democracy arose in opposition to a reigning aggregative conception of democracy in political science, solely about voting. Not long ago, political scientists arduously believed, based on logical speculations, that democratic voting is arbitrary and meaningless and that democratic voting is irrational as well. Rather than challenge these mistaken views about voting, democratic theorists instead singled out and celebrated deliberation. We review how those views about voting failed and report democratic theory’s reconciliation with voting.. Deliberative theory often says that variation in quality of deliberation can shape voting for better or worse; we add the idea that choice of voting rule can shape the value of deliberation for better or worse, illustrated with three examples. Finally, we compare the ideal values of voting and discussion, which overlap but are not identical.


2020 ◽  
pp. 40-44
Author(s):  
Yu. B. Vinslav ◽  
◽  
V. I. Lisov ◽  
A. N. Lunkin ◽  
D. A. Lunkin ◽  
...  

The authors closely consider the economic performance behavior of Russia’s top eight mining and processing plants over the period of a few years. Sustainability of the companies and high demand for their products in the market are highlighted. An important criterion of liquidity position of mining and processing plants (MPP is English for the Russian GOK) is the change in the net assets which have on the whole grown over the period under analysis from 38,5 to 52,8 BRub, i.e., 1.37 times. After a decline in the post-crisis period (2015–2016), the index of the net assets increased by 31 % in 2018. Inventories of all GOKs increased, and the annual average values jumped 2 times (Lebedinsky GOK–2.15 times, Mikhailovsky GOK–2.3 times, Kovdor GOK and Karelski Okatysh–2.4 time, other GOKs–1.2–1.5 times). This proves stability of the liquidity positions of the test companies. A steadily growing trend was observed in buildup of the permanent assets of GOKs: this index of the test companies was 9.6 BRub in 2011 and 22.9 BRub in 2018 (a 2.4 times growth). The highest rate growth was demonstrated by the largest GOKs: Lebedinsky (2.8 times), Stoilensky (3.4 times) and Kovdor (2.1 times). At the same time, there is a downward trend in profitability of the test GOKs, which, by the authors’ opinion, dictates the corporate governance improvement. Efficiency of the corporate governance and competitive ability of a company drastically depend on: capacity of equipment in each process stage; quality of interaction between process stages; balance of capacities of process stages; high-skilled staffing level of each link in the production chain; efficiency of management; quality of information accumulation of current data on the behavior of each production chain link.


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