Structural and energetic properties of nickel clusters: 2≤N≤1502 \le N \le 150

The four most stable structures of Ni$_N$ clusters with $N$ from 2 to 150 have been determined using a combination of the embedded-atom method in the version of Daw, Baskes and Foiles, the {\it variable metric/quasi-Newton} method, and our own {\it Aufbau/Abbau} method. A systematic study of energetics, structure, growth, and stability of also larger clusters has been carried through without more or less severe assumptions on the initial geometries in the structure optimization, on the symmetry, or on bond lengths. It is shown that cluster growth is predominantly icosahedral with $islands$ of {\it fcc}, {\it tetrahedral} and {\it decahedral} growth. For the first time in unbiased computations it is found that Ni$_{147}$ is the multilayer (third Mackay) icosahedron. Further, we point to an enhanced ability of {\it fcc} clusters to compete with the icosahedral and decahedral structures in the vicinity of N=79. In addition, it is shown that conversion from the {\it hcp}/anti-Mackay kind of icosahedral growth to the {\it fcc}/Mackay one occurs within a transition layer including several cluster sizes. Moreover, we present and apply different analytical tools in studying structural and energetic properties of such a large class of clusters. These include means for identifying the overall shape, the occurrence of atomic shells, the similarity of the clusters with, e.g., fragments of the {\it fcc} crystal or of a large icosahedral cluster, and a way of analysing whether the $N$-atom cluster can be considered constructed from the $(N-1)$-atom one by adding an extra atom. In addition, we compare in detail with results from chemical-probe experiment. Maybe the most central result is that first for clusters with $N$ above 80 general trends can be identified.Comment: 37 pages, 11 figure

Cognitive and emotional representations of terror attacks: A cross-cultural exploration

A questionnaire measuring cognitive and affective representations of terror risk was developed and tested in Turkey and Israel. Participants in the study were university students from the two countries (n = 351). Four equivalent factors explained terror risk cognitions in each sample: costs, vulnerability, trust, and control. A single negative emotionality factor explained the affective component of terror risk representations in both samples. All factors except control could be measured reliably. Results supported the validity of the questionnaire by showing expected associations between cognitions and emotions, as well as indicating gender differences and cultural variations. Current findings are discussed in relation to previous results, theoretical approaches, and practical implications. © 2007 Society for Risk Analysis

Effects of cinnamon (Cinnamomum zeylanicum) bark oil on testicular antioxidant values, apoptotic germ cell and sperm quality

Cinnamon and its contents have multifactorial properties such as antioxidant, anti-inflammatory and antidiabetic. Male infertility is one of the major health problems in life. The aim of this study was to investigate the effects of longterm cinnamon bark oil (CBO) ingestion on testicular antioxidant values, apoptotic germ cell and sperm quality of adult rats. Twelve male healthy Wistar rats were divided into two groups, each group containing six rats. While olive oil was given to control group, 100 mg kg 1 CBO was administered to the other group by gavage daily for 10 weeks. Body and reproductive organ weights, sperm characteristics, testicular lipid peroxidation and antioxidant enzyme activities, and testicular apoptosis via terminal deoxynucleotidyl transferase–mediated dUTP nick end labelling (TUNEL) method were examined. A significant decrease in malondialdehyde level and marked increases in reduced glutathione level, glutathione peroxidase and catalase activities were observed in rats treated with CBO compared with the control group. CBO consumption provided a significant increase in weights of testes and epididymides, epididymal sperm concentration, sperm motility and diameter of seminiferous tubules when compared with the control group. However, CBO consumption tended to decrease the abnormal sperm rate and apoptotic germ cell count, but it did not reach statistical significance. It is concluded that CBO has improvement effect on testicular oxidant–antioxidant balance and sperm quality, and its consumption may be useful for asthenozoospermic men

Quercetin attenuates carbon tetrachloride-induced testicular damage in rats

This study was conducted to investigate the effect of quercetin on carbon tetrachloride (CCl4)-induced sperm damages, testicular apoptosis and oxidative stress in male rats. Group 1 served as control, group 2 was treated with only quercetin, group 3 was treated with only CCl4 and group 4 received CCl4 + quercetin. All administrations were performed by gavage and maintained for 10 weeks. CCl4 administration caused significant decreases in absolute and relative reproductive organ weights, sperm motility, concentration and testicular glutathione peroxidase (GSH-Px) and catalase (CAT) activities, and significant increases in lipid peroxidation (LPO) level, abnormal sperm rate and testicular apoptotic cell index, along with some histopathological damages when compared to the control group. However, administration of CCl4 together with quercetin provided statistically significant improvements in LPO level, abnormal sperm rate, the degree of histopathological lesions and testicular apoptotic cell index when compared to only CCl4 group. In addition, improvements observed in absolute and relative weights of reproductive organs, sperm motility and concentration, and testicular GSH-Px and CAT activities in group 4 were statistically insignificant when compared to only CCl4 group. In conclusion, quercetin has antiperoxidative effect, and its oral administration attenuates the CCl4-induced some damages in male reproductive organs and cells by decreasing the LPO

Effectiveness of cinnamon (Cinnamomum zeylanicum) bark oil in the prevention of carbon tetrachloride-induced damages on male reproductive system

In this study, it was aimed to investigate the likelihood of detrimental effects of carbon tetrachloride (CCl4) on male reproductive system through oxidative stress mechanism and also protective effects of cinnamon bark oil (CBO). For this purpose, 28 healthy male Wistar rats were divided into four groups, seven rats in each. Group 1 received only olive oil daily; group 2 was treated with 100 mg kg 1 CBO daily; group 3 was treated with only 0.25 ml kg 1 CCl4 weekly; and group 4 received weekly CCl4 + daily CBO. All administrations were made by intragastric catheter and maintained for 10 weeks. Body and reproductive organ weights, sperm characteristics, testicular oxidative stress markers and testicular apoptosis were examined. CCl4 administration caused significant decreases in body and reproductive organ weights, testicular catalase (CAT) activity, sperm motility and concentration, and significant increases in lipid peroxidation (LPO) level, abnormal sperm rate and apoptotic index along with some histopathological damages compared with the control group. However, significant improvements were observed in absolute weights of testis and epididymis, all sperm quality parameters, LPO level, apoptotic index and testicular histopathological structure following the administration of CCl4 together with CBO when compared to group given CCl4 only. The findings of this study clearly suggest that CBO has protective effect against damages in male reproductive organs and cells induced by CCl4

Effect of cinnamon (Cinnamomum zeylanicum) bark oil on heat stress-induced changes in sperm production, testicular lipid peroxidation, testicular apoptosis, and androgenic receptor density in developing Japanese quails

The aim of this study was to investigate the effect of cinnamon bark oil (CBO) on heat stress (HS)-induced changes in sperm production, testicular lipid peroxidation, testicular apoptosis, and androgenic receptor (AR) density in developing Japanese quails. Fifteen-day-old 90 male chicks were assigned to two main groups. The first group (45 chicks) was kept in a thermoneutral room at 22 C for 24 h/day. The second group (45 chicks) was kept in a roomwith high ambient temperature at 34 C for 8 h/day (from9AM–5 PM) and at 22 C for 16 h/day. Each of these two main groups was then divided into three subgroups (CBO groups 0, 250, 500 ppm) consisting of 15 chicks (six treatment groups in 2 3 factorial order). Each of subgroups was replicated for three times and each replicate included five chicks. Heat stress caused significant decreases in body weight, spermatid and testicular sperm numbers, the density of testicular Bcl-2 (antiapoptotic marker) and AR immunopositivity, and significant increases in testicular lipid peroxidation level, the density of testicular Bax (apoptoticmarker) immunopositivity, and a Bax/Bcl-2 ratio along with some histopathologic damages. However, 250 and 500 ppm CBO supplementation provided significant improvements inHS-induced increased level of testicular lipid peroxidation, decreased number of spermatid and testicular sperm, decreased densities of Bcl-2 and AR immunopositivity, and some deteriorated testicular histopathologic lesions. In addition, although HS did not significantly affect the testicular glutathione level, addition of both 250 and 500 ppm CBO to diet of quails reared in both HS and thermoneutral conditions caused a significant increase when compared with quails without any consumption of CBO. In conclusion, HS-induced lipid peroxidation causes testicular damage in developing male Japanese quails and, consumption of CBO, which has antiperoxidative effect, protects their testes against HS

Distributive politics and regional development: assessing the territorial distribution of Turkey’s public investment

Turkey is often perceived as a country with low bureaucratic capacity and prone to political manipulation and ‘pork-barrel’. This article tests whether this is the case, by analysing the extent to which politics, rather than equity and efficiency criteria, have determined the geographical allocation of public investment across the 81 provinces of Turkey between 2005 and 2012. The results show that although the Turkish government has indeed channelled public expenditures to reward its core constituencies, socioeconomic factors remained the most relevant predictors of investment. Moreover, in contrast to official regional development policy principles, we uncover the concentration of public investment in areas with comparatively higher levels of development. We interpret this as the state bureaucracy’s intentional strategy of focussing on efficiency by concentrating resources on ‘the better off among the most in need’

Assessment of imidacloprid toxicity on reproductive organ system of adult male rats

In the current study it was aimed to investigate the toxicity of low doses of imidacloprid (IMI) on the reproductive organ systems of adult male rats. The treatment groups received 0.5 (IMI-0.5), 2 (IMI-2) or 8 mg IMI/kg body weight by oral gavage (IMI-8) for three months. The deterioration in sperm motility in IMI-8 group and epidydimal sperm concentration in IMI-2 and IMI-8 groups and abnormality in sperm morphology in IMI-8 were significant. The levels of testosterone (T) and GSH decreased significantly in group IMI-8 compared to the control group. Upon treatment with IMI, apoptotic index increased significantly only in germ cells of the seminiferous tubules of IMI-8 group when compared to control. Fragmentation was striking in the seminal DNA from the IMI-8 group, but it was much less obvious in the IMI-2 one. IMI exposure resulted in elevation of all fatty acids analyzed, but the increases were significant only in stearic, oleic, linoleic and arachidonic acids. The ratios of 20:4/20:3 and 20:4/18:2 were decreased and 16:1n-9/16:0 ratio was increased. In conclusion, the present animal experiments revealed that the treatment with IMI at NOAEL dose-levels caused deterioration in sperm parameters, decreased T level, increased apoptosis of germ cells, seminal DNA fragmentation, the depletion of antioxidants and change in disturbance of fatty acid composition. All these changes indicate the suppression of testicular function

Architecture and Gender : Lessons from Building Archaeology in Africa

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