Enhanced Formulae for Determining Both Free Length and Rate of Cylindrical Compression Springs

2015 ◽  
Vol 138 (2) ◽  
Author(s):  
Manuel Paredes

Cylindrical compression springs have been commonly exploited in mechanical systems for years and their behavior is considered as well identified. Nevertheless, it appears that, even though old research studies suggest correcting the rate formula, the main industrial software dedicated to spring design exploits the uncorrected one. In order to evaluate the accuracy of the analytical formulae for spring behavior, an experimental study was performed, which tried to cover the common design space. This study was done using the two common coil ends: closed and ground ends, and closed and not ground ends. Moreover, the accuracy of the load–length relation was investigated whereas older studies focused only on the spring rate. It appears that the common uncorrected formulae give satisfactory results only when large numbers of coils are involved. We also highlight, for the first time, that it is interesting to correct not only the spring rate but also the free length of the spring.

Author(s):  
Samuel Bowles ◽  
Herbert Gintis

Why do humans, uniquely among animals, cooperate in large numbers to advance projects for the common good? Contrary to the conventional wisdom in biology and economics, this generous and civic-minded behavior is widespread and cannot be explained simply by far-sighted self-interest or a desire to help close genealogical kin. This book shows that the central issue is not why selfish people act generously, but instead how genetic and cultural evolution has produced a species in which substantial numbers make sacrifices to uphold ethical norms and to help even total strangers. The book describes how, for thousands of generations, cooperation with fellow group members has been essential to survival. Groups that created institutions to protect the civic-minded from exploitation by the selfish flourished and prevailed in conflicts with less cooperative groups. Key to this process was the evolution of social emotions such as shame and guilt, and our capacity to internalize social norms so that acting ethically became a personal goal rather than simply a prudent way to avoid punishment. Using experimental, archaeological, genetic, and ethnographic data to calibrate models of the coevolution of genes and culture as well as prehistoric warfare and other forms of group competition, the book provides a compelling and novel account of human cooperation.


2020 ◽  
Vol 62 ◽  
pp. 32-38
Author(s):  
E. A. Dolmatov ◽  
R. B. Borzayev ◽  
A. N. Shaipov

The results of the study of the duration of the juvenile period of indigenous Chechen willow leaf pear genotypes (Pyrus salicifolia Pall.) are given in connection with the acceleration of the breeding process and the use of selected forms in pear breeding for high precocity. The studies were carried out in 2016-2019 at OOO “Orchards of Chechnya” in accordance with the Agreement on creative cooperation with the Russian Research Institute of Fruit Crop Breeding. The work was carried out in accordance with generally accepted programs and methods. The objects of the study were one-year and two-year-old pear seedlings obtained from sowing seeds of selected dwarf and low-growing local Chechen forms of willow pear (P. salicifolia Pall.), laying fruit buds on annual growths and seedlings of Caucasian pear (P. caucasica Fed.), 20 500 pcs. of each specie. The aim of the research was to study the potential of precocity of willow pear seedlings and to reveal of selected forms with the greatest degree of this trait. Stratified seeds were sown in the sowing department of the OOO “Orchards of Chechnya” production nursery in April, 2017. The seedlings were grown according to the common technology in dryland conditions on the plot with chestnut soil. The first fl owering of plants was noted in the spring, 2019. As a result of the research, for the first time on a large number of the experimental material it was found that in the off spring of the indigenous Chechen willow leaf pear genotypes, the selection of a little more than 2% of seedlings with a very short juvenile period (2 years) was possible. They are of great interest in accelerating the breeding process and in the selection of new pear varieties with high precocity. 20 willow leaf pear genotypes were selected for the further use in breeding for high precocity and as sources of the trait of short juvenile period.


2005 ◽  
Vol 24 (s-1) ◽  
pp. 171-193 ◽  
Author(s):  
Michael Gibbins ◽  
Susan A. McCracken ◽  
Steven E. Salterio

Much of what takes place in auditor-client management negotiations occurs in unobservable settings and normally does not result in publicly available archival records. Recent research has increasingly attempted to probe issues relating to accounting negotiations in part due to recent events in the financial world. In this paper, we compare recalls from the two sides of such negotiations, audit partners, and chief financial officers (CFOs), collected in two field questionnaires. We examine the congruency of the auditors' and the CFOs' negotiation recalls for all negotiation elements and features that were common across the two questionnaires (detailed analyses of the questionnaires are reported elsewhere). The results show largely congruent recall: only limited divergences in recall of common elements and features. Specifically, we show a high level of congruency across CFOs and audit partners in the type of issues negotiated, parties involved in resolving the issue, and the elements making up the negotiation process, including agreement on the relative importance of various common accounting contextual features. The analysis of the common accounting contextual features suggests that certain contextual features are consistently important across large numbers of negotiations, whether viewed from the audit partner's or the CFO's perspective, and hence may warrant future study. Finally, the comparative analysis allows us to identify certain common elements and contextual features that may influence both audit partners and CFOs to consider the accounting negotiation setting as mainly distributive (win-lose).


2010 ◽  
Vol 18 (4) ◽  
pp. 6-8
Author(s):  
Stephen W. Carmichael

Some of the receptors on the surface of cardiac muscle cells (cardiomyocytes) mediate the response of these cells to catecholamines by causing the production of the common second messenger cyclic adenosine monophosphate (cAMP). An example of such receptors are the β1- and β2-adrenergic receptors (βARs) that are heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors. Selective stimulation of these two receptor subtypes leads to distinct physiological and pathophysiological responses, but their precise location on the surface of cardiomyocytes has not been correlated with these responses. In an ingenious combination of techniques, Viacheslav Nikolaev, Alexey Moshkov, Alexander Lyon, Michele Miragoli, Pavel Novak, Helen Paur, Martin Lohse, Yuri Korchev, Sian Harding, and Julia Gorelik have mapped the function of these receptors for the first time.


Religions ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 222
Author(s):  
Elaine M. Fisher

This article makes the case that Vīraśaivism emerged in direct textual continuity with the tantric traditions of the Śaiva Age. In academic practice up through the present day, the study of Śaivism, through Sanskrit sources, and bhakti Hinduism, through the vernacular, are generally treated as distinct disciplines and objects of study. As a result, Vīraśaivism has yet to be systematically approached through a philological analysis of its precursors from earlier Śaiva traditions. With this aim in mind, I begin by documenting for the first time that a thirteenth-century Sanskrit work of what I have called the Vīramāheśvara textual corpus, the Somanāthabhāṣya or Vīramāheśvarācārasāroddhārabhāṣya, was most likely authored by Pālkurikĕ Somanātha, best known for his vernacular Telugu Vīraśaiva literature. Second, I outline the indebtedness of the early Sanskrit and Telugu Vīramāheśvara corpus to a popular work of early lay Śaivism, the Śivadharmaśāstra, with particular attention to the concepts of the jaṅgama and the iṣṭaliṅga. That the Vīramāheśvaras borrowed many of their formative concepts and practices directly from the Śivadharmaśāstra and other works of the Śaiva Age, I argue, belies the common assumption that Vīraśaivism originated as a social and religious revolution.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Evdoxia Efstathiadou ◽  
Georgia Ntatsi ◽  
Dimitrios Savvas ◽  
Anastasia P. Tampakaki

AbstractPhaseolus vulgaris (L.), commonly known as bean or common bean, is considered a promiscuous legume host since it forms nodules with diverse rhizobial species and symbiovars. Most of the common bean nodulating rhizobia are mainly affiliated to the genus Rhizobium, though strains belonging to Ensifer, Pararhizobium, Mesorhizobium, Bradyrhizobium, and Burkholderia have also been reported. This is the first report on the characterization of bean-nodulating rhizobia at the species and symbiovar level in Greece. The goals of this research were to isolate and characterize rhizobia nodulating local common bean genotypes grown in five different edaphoclimatic regions of Greece with no rhizobial inoculation history. The genetic diversity of the rhizobial isolates was assessed by BOX-PCR and the phylogenetic affiliation was assessed by multilocus sequence analysis (MLSA) of housekeeping and symbiosis-related genes. A total of fifty fast-growing rhizobial strains were isolated and representative isolates with distinct BOX-PCR fingerpriniting patterns were subjected to phylogenetic analysis. The strains were closely related to R. anhuiense, R. azibense, R. hidalgonense, R. sophoriradicis, and to a putative new genospecies which is provisionally named as Rhizobium sp. I. Most strains belonged to symbiovar phaseoli carrying the α-, γ-a and γ-b alleles of nodC gene, while some of them belonged to symbiovar gallicum. To the best of our knowledge, it is the first time that strains assigned to R. sophoriradicis and harbored the γ-b allele were found in European soils. All strains were able to re-nodulate their original host, indicating that they are true microsymbionts of common bean.


Author(s):  
Nooreddine Iskandar ◽  
Tatiana Rahbany ◽  
Ali Shokor

Abstract Background: Due to the common instability caused by political and security issues, Lebanese hospitals have experienced acts of terrorism multiple times. The most recent Beirut Explosion even forced several hospitals to cease operations for the first time in decades—but studies show the preparedness levels for such attacks in similar countries are low. Objective: The aim of this study is to explore the experience of Lebanese hospitals with terrorist attacks. Methods: This qualitative study used semi-structured interviews with various stakeholders to assess their experience with terrorist bombings. Data was analyzed using the thematic analysis method. Results: The researchers found that Lebanese hospitals vary greatly in their structures and procedures. Those differences are a function of 3 contextual factors: location, culture, and accreditation status. Hospitals found near ‘dangerous zones’ were more likely to be aware and to have better response to such events. A severe lack of communication, unity of command, and collaboration between stakeholders has made the process fragmented. Conclusion: The researchers recommend a larger role for the Ministry of Public Health (MOPH) in this process, and the creation of a platform where Lebanese organizations can share their experiences to improve preparedness and resilience of the Lebanese healthcare system in the face of terrorism.


1991 ◽  
Vol 106 (3) ◽  
pp. 459-465 ◽  
Author(s):  
F. E. Donald ◽  
R. C. B. Slack ◽  
G. Colman

SUMMARYIsolates of Streptococcus pyogenes from vaginal swabs of children with vulvovaginitis received at Nottingham Public Health Laboratory during 1986–9 were studied. A total of 159 isolates was made during the 4 years, increasing from 17 in 1986 to 64 in 1989 and accounting for 11% of all vaginal swabs received from children. The numbers of throat swabs yielding S. pyogenes also showed an increase from 974 in 1986 to 1519 in 1989. A winter peak of isolates was noted for both vaginal swabs and throat swabs. A total of 98 strains from vaginal swabs were serotyped: 22 different types were identified, 61% of which were the common types M4, M6, R28 and M12. Erythromycin sensitivity was done on 89 strains; 84% were highly sensitive (MIC < 0·03 mg/1). There are no other reports of such large numbers in the literature; the reason for seeing this increase in Nottingham is unclear.


Often bizarre in shape and gaudily coloured, the opisthobranchs of the tropical IndoPacific have always been attractive subjects for the specialist worker and for writers of popular natural history. There is certainly no lack of papers describing their anatomy and systematics (Marcus & Burch (1965) give a fairly full bibliography), but only in those by Risbec (1928 a, b , 1951, 1953) are there descriptions of where or how they live and his statements are brief and rather vague. I collected opisthobranchs so as to record them for the British Solomon Islands for the first time and, whenever possible, I noted their habits and habitats. My observations on gut contents are rather scanty as I did not wish to damage any of the few specimens of each species collected. From an examination of ten different types of reef formation I discovered that opisthobranchs are common in only two places; (1) the crest of a semi-exposed reef where algae occur in pools, and (2) the flat of a sheltered or semi-sheltered reef. At each of these sites several distinct habitats can be distinguished. Unfortunately my recognition of these habitats is not supported by strong numerical evidence as none of the 55 species occurred in large numbers.


Author(s):  
A. L. Lebedev ◽  
I. V. Avilina

Experimental study of kinetics of dissolution of hypso anhydrites at 25 ᵒC made it possible to formulate model of the process in the form of a balance equation for the kinetics of dissolution of gypsum, anhydrite (first and second orders, respectively) and kinetics of precipitation of gypsum (second order). The processing of the experimental data were carried out on the basis of the solution of the Riccati equation. When taking into account the common-ion effect on the solubility of gypsum and anhydrite, the calculated values turned out to be more comparable with the experimental ones.


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