Elements of the Diagenesis of Sedimentary Rocks

1990 ◽  
Vol 195 ◽  
Author(s):  
Morrel H. Cohen

ABSTRACTThree of the most important elements of the diagenesis of sedimentary rocks are consolidation, porosity reduction, and pressure dissolution or cementation. These are discussed qualitatively with special emphasis on the central role of contact formation in controlling both the driving forces and the kinetics of morphological change. It is shown, in particular, that the equilibrium forces would drive the rocks towards collapse of their porosity earlier in diagenesis were they not prevented by kinetic barriers. At greater depths these barriers are effectively removed by pressure concentration at the small contacts. We propose an explicit, qualitative mechanism leading to the observed morphologies and identify specific problems for quantitative analysis.

2011 ◽  
Vol 172-174 ◽  
pp. 1207-1213 ◽  
Author(s):  
Yong Chang Liu ◽  
F. Sommer ◽  
Eric J. Mittemeijer

The formation of ferrite (α) from austenite (γ) and vice versa, upon thermo-mechanical processing of steels, are phase transformations of great technological importance. Often these transformations occur in the presence of externally or internally imposed stress. This paper provides an overview of recent research on the quantitative analysis of the transformation kinetics of the γ®a and a®g transformations subjected to uniaxial compressive stress below the yield stress of g and a, based on the application of the high-resolution differential dilatometry and the modular model of transformation kinetics. The application of uniaxially compressive stresses leads to antagonistic effects on the transformation kinetics: the stress applied upon the γ®a transformation prompts the transformation, while it obstructs the a®g transformation. These results can be quantitatively discussed in terms of chemical driving forces and transformation-induced deformation energies.


2013 ◽  
Vol 18 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Robert J. Barth

Abstract Scientific findings have indicated that psychological and social factors are the driving forces behind most chronic benign pain presentations, especially in a claim context, and are relevant to at least three of the AMA Guides publications: AMA Guides to Evaluation of Disease and Injury Causation, AMA Guides to Work Ability and Return to Work, and AMA Guides to the Evaluation of Permanent Impairment. The author reviews and summarizes studies that have identified the dominant role of financial, psychological, and other non–general medicine factors in patients who report low back pain. For example, one meta-analysis found that compensation results in an increase in pain perception and a reduction in the ability to benefit from medical and psychological treatment. Other studies have found a correlation between the level of compensation and health outcomes (greater compensation is associated with worse outcomes), and legal systems that discourage compensation for pain produce better health outcomes. One study found that, among persons with carpal tunnel syndrome, claimants had worse outcomes than nonclaimants despite receiving more treatment; another examined the problematic relationship between complex regional pain syndrome (CRPS) and compensation and found that cases of CRPS are dominated by legal claims, a disparity that highlights the dominant role of compensation. Workers’ compensation claimants are almost never evaluated for personality disorders or mental illness. The article concludes with recommendations that evaluators can consider in individual cases.


2004 ◽  
pp. 129-140 ◽  
Author(s):  
M. Tretyakov

The article focuses on the analysis of the process of convergence of outsider and insider models of corporate governance. Chief characteristics of basic and intermediate systems of corporate governance as well as the changing role of its main agents are under examination. Globalization of financial and commodity markets, convergence of legal systems, an open exchange of ideas and information are the driving forces of the convergence of basic systems of corporate governance. However the convergence does not imply the unification of institutional environment and national institutions of corporate governance.


Sains Insani ◽  
2018 ◽  
Vol 2 (1) ◽  
pp. 17-27
Author(s):  
Megat Ayop Megat Arifin ◽  
Abd. Halim Ahmad

Whitsleblowing is one of the positive practices in organizations that are able to raise the level of integrity among the members of an organization. However, the roles of whistleblowing also inevitably invites a response, especially among members of the organization itself. This is because such practices are viewed as one factor that may be detrimental to the organization in addition to revealing the reporter (whistleblower) to some external threats and intimidation of discrimination within the organization. This paper is an attempt to examine the relationship between perceptions of members of the Royal Malaysian Police (RMP) Contingent of Perak through the role of whistleblowing practices to increase the perception of the integrity of the members. Next, identify the purpose of the whistleblowing and its effect on the integrity of the members of the organization. This study used a descriptive quantitative analysis to identify patterns of relationship that exists between the perception of whistleblowing practices with perceptions of increased integrity based on three basic variables of demographic factors, response to whistleblowing and the impact of making the report. The results showed that members of the Perak’s police have a positive perception of whistleblowing practices which are seen to be done in improving the integrity of the members.Keywords: whistleblowing, perception, RMP members, culture, integrity, organization, influence. ABSTRAK: Whitsleblowing merupakan salah satu amalan positif dalam organisasi yang mampu untuk meningkatkan tahap integriti ahli-ahli dalam sesebuah organisasi. Namun begitu, amalan whistleblowing juga turut tidak dapat mengelak daripada mengundang pelbagai respon khususnya dalam kalangan ahli organisasi itu sendiri. Amalan sebegini turut dilihat sebagai salah satu faktor yang boleh memudaratkan organisasi di samping mendedahkan pelapor (whistleblower) kepada beberapa bentuk ancaman ugutan dari luar dan diskriminasi dalam organisasi. Kertas ini merupakan satu upaya untuk melihat perkaitan antara persepsi anggota Polis Diraja Malaysia (PDRM) Kontinjen Perak melalui peranan amalan whistleblowing terhadap persepsi peningkatan integriti anggota. Seterusnya, mengenalpasti maksud whistleblowing dan pengaruhnya terhadap tahap integriti anggota dalam organisasi. Kajian ini menggunakan analisis kuantitatif berbentuk deskriptif bagi mengenalpasti corak hubungan yang wujud antara persepsi terhadap amalan whistleblowing dengan persepsi terhadap peningkatan integriti berdasarkan tiga pembolehubah asas iaitu faktor demografi, tanggapan terhadap whistleblowing dan kesan daripada tindakan membuat laporan. Dapatan kajian menunjukkan bahawa anggota PDRM Perak mempunyai persepsi yang positif terhadap whistleblowing yang mana ianya dilihat perlu dilaksanakan dalam meningkatkan integriti anggota.Kata kunci: whistleblowing, persepsi, amalan, anggota PDRM, budaya, integriti, organisasi, pengaruh.  


1993 ◽  
Vol 58 (5) ◽  
pp. 1001-1006 ◽  
Author(s):  
Oľga Vollárová ◽  
Ján Benko

The kinetics of oxidation of [Co(en)2SCH2COO]+ with S2O82- was studied in water-methanol and water-tert-butyl alcohol mixtures. Changes in the reaction activation parameters ∆H≠ and ∆S≠ with varying concentration of the co-solvent depend on the kind of the latter, which points to a significant role of salvation effects. The solvation effect on the reaction is discussed based on a comparison of the transfer functions ∆Ht0, ∆St0 and ∆Gt0 for the initial and transition states with the changes in the activation parameters accompanying changes in the CO-solvent concentration. The transfer enthalpies of the reactant were obtained from calorimetric measurements.


Author(s):  
Paul Stoneman ◽  
Eleonora Bartoloni ◽  
Maurizio Baussola

This chapter explores the factors that affect the firm’s decision to undertake product innovation. The discussion encompasses the driving forces that encourage product innovation, for example innovation by others or the ageing of an existing product line; however, the basic rationale is the search for profits. The chapter also addresses decisions about: the extent of innovation in general; horizontal and vertical product innovations separately; and the location of innovations in product space. The role of market structures in the product innovation decision, uncertainty in the innovating environment, and issues relating to emulation and copying are also addressed. Constraints to product innovation that survey data indicate are most important—innovation costs, risk and finance, and the availability of qualified labour—are also addressed.


Author(s):  
Aminata Hallimat Cissé ◽  
Sandrine Lioret ◽  
Blandine de Lauzon-Guillain ◽  
Anne Forhan ◽  
Ken K. Ong ◽  
...  

Abstract Background Early adiposity rebound (AR) has been associated with increased risk of overweight or obesity in adulthood. However, little is known about early predictors of age at AR. We aimed to study the role of perinatal factors and genetic susceptibility to obesity in the kinetics of AR. Methods Body mass index (BMI) curves were modelled by using mixed-effects cubic models, and age at AR was estimated for 1415 children of the EDEN mother–child cohort study. A combined obesity risk-allele score was calculated from genotypes for 27 variants identified by genome-wide association studies of adult BMI. Perinatal factors of interest were maternal age at delivery, parental education, parental BMI, gestational weight gain, maternal smoking during pregnancy, and newborn characteristics (sex, prematurity, and birth weight). We used a hierarchical level approach with multivariable linear regression model to investigate the association between these factors, obesity risk-allele score, and age at AR. Results A higher genetic susceptibility to obesity score was associated with an earlier age at AR. At the most distal level of the hierarchical model, maternal and paternal educational levels were positively associated with age at AR. Children born to parents with higher BMI were more likely to exhibit earlier age at AR. In addition, higher gestational weight gain was related to earlier age at AR. For children born small for gestational age, the average age at AR was 88 [±39] days lower than for children born appropriate for gestational age and 91 [±56] days lower than for children born large for gestational age. Conclusion The timing of AR seems to be an early childhood manifestation of the genetic susceptibility to adult obesity. We further identified low birth weight and gestational weight gain as novel predictors of early AR, highlighting the role of the intrauterine environment in the kinetics of adiposity.


2021 ◽  
Vol 22 (7) ◽  
pp. 3787
Author(s):  
Hussam Ibrahim ◽  
Philipp Reus ◽  
Anna Katharina Mundorf ◽  
Anna-Lena Grothoff ◽  
Valerie Rudenko ◽  
...  

Repressor protein period (PER) complexes play a central role in the molecular oscillator mechanism of the mammalian circadian clock. While the main role of nuclear PER complexes is transcriptional repression, much less is known about the functions of cytoplasmic PER complexes. We found with a biochemical screen for PER2-interacting proteins that the small GTPase regulator GTPase-activating protein and VPS9 domain-containing protein 1 (GAPVD1), which has been identified previously as a component of cytoplasmic PER complexes in mice, is also a bona fide component of human PER complexes. We show that in situ GAPVD1 is closely associated with casein kinase 1 delta (CSNK1D), a kinase that regulates PER2 levels through a phosphoswitch mechanism, and that CSNK1D regulates the phosphorylation of GAPVD1. Moreover, phosphorylation determines the kinetics of GAPVD1 degradation and is controlled by PER2 and a C-terminal autoinhibitory domain in CSNK1D, indicating that the regulation of GAPVD1 phosphorylation is a novel function of cytoplasmic PER complexes and might be part of the oscillator mechanism or an output function of the circadian clock.


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