Bulletin No. 169 - The Use of Alkali Water for Irrigation

Because of the scanty rainfall of arid regions, the soluble materials in the rocks and soil are not leached out as they are where the rainfall is high. As a result, the accumulation of excessive quantities of soluble salts is likely to be a menace to arid soils. Farm practices must be directed toward preventing this condition

Depinning transition of dislocation assemblies: pileup and low-angle grain boundary

We investigate the depinning transition occurring in dislocation assemblies. In particular, we consider the cases of regularly spaced pileups and low angle grain boundaries interacting with a disordered stress landscape provided by solute atoms, or by other immobile dislocations present in non-active slip systems. Using linear elasticity, we compute the stress originated by small deformations of these assemblies and the corresponding energy cost in two and three dimensions. Contrary to the case of isolated dislocation lines, which are usually approximated as elastic strings with an effective line tension, the deformations of a dislocation assembly cannot be described by local elastic interactions with a constant tension or stiffness. A nonlocal elastic kernel results as a consequence of long range interactions between dislocations. In light of this result, we revise statistical depinning theories and find novel results for Zener pinning in grain growth. Finally, we discuss the scaling properties of the dynamics of dislocation assemblies and compare theoretical results with numerical simulations.Comment: 13 pages, 8 figure

Depinning transition of dislocation assemblies: pileup and low-angle grain boundary

We investigate the depinning transition occurring in dislocation assemblies. In particular, we consider the cases of regularly spaced pileups and low angle grain boundaries interacting with a disordered stress landscape provided by solute atoms, or by other immobile dislocations present in non-active slip systems. Using linear elasticity, we compute the stress originated by small deformations of these assemblies and the corresponding energy cost in two and three dimensions. Contrary to the case of isolated dislocation lines, which are usually approximated as elastic strings with an effective line tension, the deformations of a dislocation assembly cannot be described by local elastic interactions with a constant tension or stiffness. A nonlocal elastic kernel results as a consequence of long range interactions between dislocations. In light of this result, we revise statistical depinning theories and find novel results for Zener pinning in grain growth. Finally, we discuss the scaling properties of the dynamics of dislocation assemblies and compare theoretical results with numerical simulations.Comment: 13 pages, 8 figure

IEEE Access Special Section Editorial : Complex Network Analysis and Engineering in 5G and Beyond Toward 6G

Peer reviewedPublisher PD

Dispersion force for materials relevant for micro and nanodevices fabrication

The dispersion (van der Waals and Casimir) force between two semi-spaces are calculated using the Lifshitz theory for different materials relevant for micro and nanodevices fabrication, namely, gold, silicon, gallium arsenide, diamond and two types of diamond-like carbon (DLC), silicon carbide, silicon nitride and silicon dioxide. The calculations were performed using recent experimental optical data available in the literature, usually ranging from the far infrared up to the extreme ultraviolet bands of the electromagnetic spectrum. The results are presented in the form of a correction factor to the Casimir force predicted between perfect conductors, for the separation between the semi-spaces varying from 1 nanometre up to 1 micrometre. The relative importance of the contributions to the dispersion force of the optical properties in different spectral ranges is analyzed. The role of the temperature for semiconductors and insulators is also addressed. The results are meant to be useful for the estimation of the impact of the Casimir and van der Waals forces on the operational parameters of micro and nanodevices

Brain erythropoietin fine-tunes a counterbalance between neurodifferentiation and microglia in the adult hippocampus

In adult cornu ammonis hippocampi, erythropoietin (EPO) expression drives the differentiation of new neurons, independent of DNA synthesis, and increases dendritic spine density. This substantial brain hardware upgrade is part of a regulatory circle: during motor-cognitive challenge, neurons experience ‘‘functional’’ hypoxia, triggering neuronal EPO production, which in turn promotes improved performance. Here, we show an unexpected involvement of resident microglia. During EPO upregulation and stimulated neurodifferentiation, either by functional or inspiratory hypoxia, microglia numbers decrease. Treating mice with recombinant human (rh)EPO or exposure to hypoxia recapitulates these changes and reveals the involvement of neuronally expressed IL-34 and microglial CSF1R. Surprisingly, EPO affects microglia in phases, initially by inducing apoptosis, later by reducing proliferation, and overall dampens microglia activity and metabolism, as verified by selective genetic targeting of either the microglial or pyramidal neuronal EPO receptor. We suggest that during accelerating neuronal differentiation, EPO acts as regulator of the CSF1R-dependent microglia

Probing a Complex of Cytochromecand Cardiolipin by Magnetic Circular Dichroism Spectroscopy: Implications for the Initial Events in Apoptosis

Oxidation of cardiolipin (CL) by its complex with cytochrome c (cyt c) plays a crucial role in triggering apoptosis. Through a combination of magnetic circular dichroism spectroscopy and potentiometric titrations, we show that both the ferric and ferrous forms of the heme group of a CL:cyt c complex exist as multiple conformers at a physiologically relevant pH of 7.4. For the ferric state, these conformers are His/Lys- and His/OH–-ligated. The ferrous state is predominantly high-spin and, most likely, His/–. Interconversion of the ferric and ferrous conformers is described by a single midpoint potential of -80 ± 9 mV vs SHE. These results suggest that CL oxidation in mitochondria could occur by the reaction of molecular oxygen with the ferrous CL:cyt c complex in addition to the well-described reaction of peroxides with the ferric form

Koliko su studenti više medicinske škole u Bitoli upoznati s problemom infekcije HCV-om

Healthcare workers are at risk of occupationally-acquired viral infections such as human immunodefi ciency virus (HIV), hepatitis B (HBV), and hepatitis C (HCV). HCV is parenterally transmitted and has been found in every part of the world. This cross-sectional study was conducted to establish the awareness and attitude about HCV infections among 210 full-time and part-time nursing students of the Medical College in Bitola, Macedonia ‘from May to June 2009. For this purpose we used a self-administered questionnaire which consisted of three parts. The fi rst included demographic data, the second included questions about causes of infection, mode of transmission, symptoms, acute and chronic hepatitis, and prevention, and the third questions about students’ attitude toward patients with suspect or confi rmed HCV infection. Full-time students showed higher HCV awareness (84 %) than part-time students (69 %). 58 % of the full-time and 79 % of the part-time students said they would not avoid professional contact with suspect or HCV infected patients. Our study has shown that even though both groups of students have a suffi cient knowledge about HCV to face future challenges, they need further education on the subject. Practical recommendations would help to reduce stigmatising behaviour still further.Zdravstveni su radnici izloženi profesionalnomu riziku od infekcije virusom humane imunodefi cijencije (HIV-om), hepatitis B virusom (HBV-om) te hepatitis C virusom (HCV-om). HCV se prenosi parenteralno i ima ga posvuda u svijetu. Ovo smo presječno ispitivanje proveli da utvrdimo koliko su studenti za medicinske tehničare i sestre upoznati s infekcijom HCV-om i saznamo njihove stavove o tome. Ispitivanje je obuhvatilo 210 redovitih i izvanrednih studenata Visoke medicinske škole u Bitoli i trajalo je od svibnja do lipnja 2009. Za ispitivanje je rabljen opširan upitnik. Odgovori su pokazali da redoviti studenti imaju bolji uvid u predmet (s 84 % točnih odgovora) od izvanrednih studenata (69 %). U pogledu stava prema pacijentima 58 % redovitih i 79 % izvanrednih studenata ne izbjegava dodir s pacijentima koji su infi cirani HCV-om. Ispitivanje je pokazalo da su studenti iz obje skupine dovoljno upoznati s infekcijom HCV-om, rizičnim čimbenicima i načinom prijenosa, ali je potrebno to znanje nadograditi

Living between languages: The politics of translation in Leila Aboulela’s Minaret and Xiaolu Guo’s A Concise Chinese-English Dictionary for Lovers

This is the author's final draft post-refereeing as published in The Journal of Commonwealth Literature 2012 47: 207 DOI:10.1177/0021989412440433. The online version of this article can be found at: http://jcl.sagepub.com/content/47/2/20