Life-cycle costing of metallic structures

Structural material selection has traditionally been based on Initial material cost. However, growing pressure on the construction industry to consider the longer-term financial and environmental implications of projects is encouraging a more holistic view. Thus, materials with higher initial costs, but which offer cost savings over the life cycle of a structure, are gaining increasing recognition. The life-cycle costs of structures of two such metallic materials, namely aluminium alloy and stainless steel, are compared with those of ordinary structural carbon steel in the present study. Two structural applications - a typical office building and a bridge - are analysed, while offshore applications are briefly discussed. The ratio of initial material cost per tonne was assumed to be 1.0:2.5:4.0 (carbon steel:aluminium alloy:stainless steel). Following a preliminary structural design to current European design standards taking due account of the material densities and structural properties (principally strength and stiffness), it was found that on an initial cost basis, carbon steel offers the most competitive solution for both the building and the bridge. However, considering the additional life-cycle costs including maintenance costs, end-of-life costs and the residual value of the structure (appropriately discounted to present values), the results indicate that carbon steel offers the most competitive life-cycle solution for the office building but delivers the most expensive life-cycle solution for the bridge. Overall, it is concluded that on a whole-life basis aluminium alloy and stainless steel may offer more competitive solutions than carbon steel for bridges and exposed areas of building structures

A Study of hypomagnesemia in critically ill patients and its correlation with patient outcomes

Background: Magnesium (Mg) is essential for life and plays a key role in the human body's various biochemical and physiological processes. Hypomagnesemia is common in all hospitalized patients, especially with co-existing electrolyte abnormalities in critically ill patients. Hypomagnesemia, if not diagnosed on time and appropriately treated, can cause serious and potentially fatal complications and is associated with increased mortality.Aim and Objectives: To study hypomagnesemia in critically ill patients and its correlation with patient outcomes considering the following parameters: Age, Sex, Diabetic status, Association with other lab parameters, APACHE II score, Need for ventilator support, Length of stay in ICU, Total stay in the hospital, Mortality.Materials and Methods: The study was a prospective study done in the Department of General Medicine (Medical ICU), Sri Ramachandra Medical College and Research Institute from September 2016 to August 2017. A thorough clinical examination was done; clinical data were recorded into the EXCEL case sheet. Serum calcium, serum potassium, ABG, along with other basic labs was sent for all patients. APACHE II score was calculated and all parameters were entered into an excel sheet. The results of the study were analyzed and statistical data was summarized using SPSS 17 software. Pearson Correlation, Kendall Tau B, Student t-test, and ANOVA were done for specific variables.Results: A total of 1067 patients admitted in ICU between September 2016 to August 2017 were taken into the study out of which 169 patients had hypomagnesemia (< 1.8 mg/ dl). Various correlations were analyzed for age, sex, diabetic status, APACHE II score, serum calcium, serum potassium, ventilator requirement, ICU stay, hospital stay, and outcome. A total of 169 patients out of 1067 patients had hypomagnesemia in the present study (15.83%). The minimum magnesium value was 0.8 mg/dl and the maximum value was 1.7 mg/dL. The present study highlighted the importance of hypomagnesemia in intensive care unit and its outcome with various parameters. The present study showed that hypomagnesemia is associated with increased APACHE II score, increased incidence of ventilator requirement and higher mortality.Conclusion: Magnesium is an unrecognized cation in critically ill patients. The incidence of hypomagnesemia in the present study was less compared to other studies done in medically ill patients. Hypomagnesemia correlated well with APACHE II score, ventilator requirement, and mortality, which was statistically significant.&nbsp

Women on boards and firm performance

This study investigates the financial performance of Dutch companies both with and without women on their boards. The analysis extends earlier methods used in research by Catalyst (The bottom line: corporate performance and women's representation on boards, 2007) and McKinsey (Women matter. Gender diversity, a corporate performance driver. McKinsey & Company, USA, 2007), two studies that are often cited in the literature, although, each has a number of methodological shortcomings. This article adds to the international debate, which is often normative, through examining 99 listed companies in the Dutch Female Board Index. Our results show that firms with women directors perform better than those without women on their boards

The Cyprinodon variegatus genome reveals gene expression changes underlying differences in skull morphology among closely related species

Genes in durophage intersection set at 15 dpf. This is a comma separated table of the genes in the 15 dpf durophage intersection set. Given are edgeR results for each pairwise comparison. Columns indicating whether a gene is included in the intersection set at a threshold of 1.5 or 2 fold are provided. (CSV 13 kb

Isolated and dynamical horizons and their applications

Over the past three decades, black holes have played an important role in quantum gravity, mathematical physics, numerical relativity and gravitational wave phenomenology. However, conceptual settings and mathematical models used to discuss them have varied considerably from one area to another. Over the last five years a new, quasi-local framework was introduced to analyze diverse facets of black holes in a unified manner. In this framework, evolving black holes are modeled by dynamical horizons and black holes in equilibrium by isolated horizons. We review basic properties of these horizons and summarize applications to mathematical physics, numerical relativity and quantum gravity. This paradigm has led to significant generalizations of several results in black hole physics. Specifically, it has introduced a more physical setting for black hole thermodynamics and for black hole entropy calculations in quantum gravity; suggested a phenomenological model for hairy black holes; provided novel techniques to extract physics from numerical simulations; and led to new laws governing the dynamics of black holes in exact general relativity.Comment: 77 pages, 12 figures. Typos and references correcte

[SWI+], the Prion Formed by the Chromatin Remodeling Factor Swi1, Is Highly Sensitive to Alterations in Hsp70 Chaperone System Activity

The yeast prion [SWI+], formed of heritable amyloid aggregates of the Swi1 protein, results in a partial loss of function of the SWI/SNF chromatin-remodeling complex, required for the regulation of a diverse set of genes. Our genetic analysis revealed that [SWI+] propagation is highly dependent upon the action of members of the Hsp70 molecular chaperone system, specifically the Hsp70 Ssa, two of its J-protein co-chaperones, Sis1 and Ydj1, and the nucleotide exchange factors of the Hsp110 family (Sse1/2). Notably, while all yeast prions tested thus far require Sis1, [SWI+] is the only one known to require the activity of Ydj1, the most abundant J-protein in yeast. The C-terminal region of Ydj1, which contains the client protein interaction domain, is required for [SWI+] propagation. However, Ydj1 is not unique in this regard, as another, closely related J-protein, Apj1, can substitute for it when expressed at a level approaching that of Ydj1. While dependent upon Ydj1 and Sis1 for propagation, [SWI+] is also highly sensitive to overexpression of both J-proteins. However, this increased prion-loss requires only the highly conserved 70 amino acid J-domain, which serves to stimulate the ATPase activity of Hsp70 and thus to stabilize its interaction with client protein. Overexpression of the J-domain from Sis1, Ydj1, or Apj1 is sufficient to destabilize [SWI+]. In addition, [SWI+] is lost upon overexpression of Sse nucleotide exchange factors, which act to destabilize Hsp70's interaction with client proteins. Given the plethora of genes affected by the activity of the SWI/SNF chromatin-remodeling complex, it is possible that this sensitivity of [SWI+] to the activity of Hsp70 chaperone machinery may serve a regulatory role, keeping this prion in an easily-lost, meta-stable state. Such sensitivity may provide a means to reach an optimal balance of phenotypic diversity within a cell population to better adapt to stressful environments