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Aneuploidy, which refers to unbalanced chromosome numbers, represents a class of genetic variation that is associated with cancer, birth defects and eukaryotic micro-organisms.sup.1-4. Whereas it is known that each aneuploid chromosome stoichiometry can give rise to a distinct pattern of gene expression and phenotypic profile.sup.4,5, it remains a fundamental question as to whether there are common cellular defects that are associated with aneuploidy. Here we show the existence in budding yeast of a common aneuploidy gene-expression signature that is suggestive of hypo-osmotic stress, using a strategy that enables the observation of common transcriptome changes of aneuploidy by averaging out karyotype-specific dosage effects in aneuploid yeast-cell populations with random and diverse chromosome stoichiometry. Consistently, aneuploid yeast exhibited increased plasma-membrane stress that led to impaired endocytosis, and this defect was also observed in aneuploid human cells. Thermodynamic modelling showed that hypo-osmotic-like stress is a general outcome of the proteome imbalance that is caused by aneuploidy, and also predicted a relationship between ploidy and cell size that was observed in yeast and aneuploid cancer cells. A genome-wide screen uncovered a general dependency of aneuploid cells on a pathway of ubiquitin-mediated endocytic recycling of nutrient transporters. Loss of this pathway, coupled with the endocytic defect inherent to aneuploidy, leads to a marked alteration of intracellular nutrient homeostasis. A common aneuploidy gene-expression signature is identified in yeast that is suggestive of hypo-osmotic stress, and which leads to cells that exhibit increased plasma-membrane stress and impaired endocytosis., Author(s): Hung-Ji Tsai [sup.1] , Anjali R. Nelliat [sup.1] [sup.2] , Mohammad Ikbal Choudhury [sup.3] , Andrei Kucharavy [sup.1] , William D. Bradford [sup.4] , Malcolm E. Cook [sup.4] , [...]

This article examines the position of Bangladesh in the field of international social work with women. It explores the country's women's development initiatives in the context of the global debate over indigenization, universalization and imperialism. To identify the strategic position, the article examines the literature on social work, the evolution of social work and the web contents of some development agencies in Bangladesh. The findings reveal that Bangladesh follows a process of reconciliation in the indigenization–internationalization dispute by employing both top-down (think globally, act locally) and bottom-up (act locally, proceed globally) approaches to international social work and women's development. [ABSTRACT FROM AUTHOR]

A high quality joint between tool steel and stainless steel alloys is hard to achieve with the conventional welding process. In this study, a new process of joining semi-solid AISI D2 tool steel and AISI 304 stainless steel using a partial remelting method is proposed. Metallographic analysis and Vickers hardness tests were performed. The results obtained from investigating the basic geometries demonstrated a good joining quality that differs from the conventional process of welding or mechanical joining with screws or nails. Metallographic analyses along the joint interface between semi-solid AISI D2 and 304 stainless steel showed a smooth transition from one to the other, with neither oxides nor microcracking being observed. Local mechanical properties of different regions show three different readings according to the results of the hardness tests. The current work successfully confirmed that the avoidance of dendritic microstructure of the semi-solid joined zone and high bonding quality components can be achieved. From the present study, it can be said that the thixojoining process can be utilized safely for dissimilar metal pairs.

An analytical basis is established in this paper for a programmed function of known amplitude to be added to the feedback path of a hysteresis current controller (HCC) in a static power inverter. Improper amplitude and slope of the carrier waveform in a modulated carrier HCC frequently encounter the problem of sudden high frequency switching. Though intuitive approaches exists to tackle the problem practically, proper analytical basis has not been established so far. This paper deals with solving the problem analytically, so that implementation of such scheme for an inverter operation can be done systematically and accurately. A theoretical model of programmed ramp comparison HCC (PRCHCC) is developed in this paper that defines a carrier waveform based on inverter supply voltage, load parameters and reference current waveform. The parameters of the carrier waveform of PRCHCC can be deterministically predicted for uniform switching frequency operation. Simulation and experimental results highlights the potential of the proposed model for uniform switching at all operating conditions. Index Terms--Current controller, HCC, inverters, PWM, uniform switching.