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The archaeological site of Saruq al-Hadid, Dubai, United Arab Emirates, presents a long sequence of persistent temporary human occupation on the northern edge of the Rub’ al-Khali desert. The site is located in active dune fields, and evidence for human activity is stratified within a deep sequence of natural dune deposits that reflect complex taphonomic processes of deposition, erosion and reworking. This study presents the results of a program of radiocarbon (14C) and thermoluminescence dating on deposits from Saruq al-Hadid, allied with studies of material remains, which are amalgamated with the results of earlier absolute dating studies provide a robust chronology for the use of the site from the Bronze Age to the Islamic period. The results of the dating program allow the various expressions of human activity at the site—ranging from subsistence activities such as hunting and herding, to multi-community ritual activities and large scale metallurgical extraction—to be better situated chronologically, and thus in relation to current debates regarding the development of late prehistoric and early historic societies in southeastern Arabia.
Using multilevel models, we examined mother-, father-, and child-reported (N = 1,336 families) externalizing behavior problem trajectories from age 7 to 14 in nine countries (China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States). The intercept and slope of children's externalizing behavior trajectories varied both across individuals within culture and across cultures, and the variance was larger at the individual level than at the culture level. Mothers’ and children's endorsement of aggression as well as mothers’ authoritarian attitudes predicted higher age 8 intercepts of child externalizing behaviors. Furthermore, prediction from individual-level endorsement of aggression and authoritarian attitudes to more child externalizing behaviors was augmented by prediction from cultural-level endorsement of aggression and authoritarian attitudes, respectively. Cultures in which father-reported endorsement of aggression was higher and both mother- and father-reported authoritarian attitudes were higher also reported more child externalizing behavior problems at age 8. Among fathers, greater attributions regarding uncontrollable success in caregiving situations were associated with steeper declines in externalizing over time. Understanding cultural-level as well as individual-level correlates of children's externalizing behavior offers potential insights into prevention and intervention efforts that can be more effectively targeted at individual children and parents as well as targeted at changing cultural norms that increase the risk of children's and adolescents’ externalizing behavior.
We report on the results of coherent X-ray diffraction imaging (CXDI) and ptychography measurements of two individual core-shell-shell GaAs/(In,Ga)As/GaAs nanowires (NWs) grown by molecular beam epitaxy (MBE) on patterned Si(111) substrate. CXDI at the axial GaAs 111 Bragg reflection was applied at different positions along the NW axis in order to characterize the NWs in terms of structural homogeneity along the radial directions. At each positon 3D reciprocal space maps have been recoded and inverted using phase retrieval algorithms. The CXDI were complemented by 2D ptychography measurements at GaAs 111 Bragg reflection probing the same NWs with respect to their structural homogeneity. Both methods provide structural homogeneity for NW1 and NW2 except at the bottom part of the NWs. In case of NW2 CXDI and ptychography show changes in the structure of the top part of the NW indicated by 60° rotation of the indicated three-fold rotational symmetry in the observed diffraction patterns and changes in the strain field reconstructed from ptychography.
Using data from 1,177 families in eight countries (Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States), we tested a conceptual model of direct effects of childhood family adversity on subsequent externalizing behaviors as well as indirect effects through psychological mediators. When children were 9 years old, mothers and fathers reported on financial difficulties and their use of corporal punishment, and children reported perceptions of their parents’ rejection. When children were 10 years old, they completed a computerized battery of tasks assessing reward sensitivity and impulse control and responded to questions about hypothetical social provocations to assess their hostile attributions and proclivity for aggressive responding. When children were 12 years old, they reported on their externalizing behavior. Multigroup structural equation models revealed that across all eight countries, childhood family adversity had direct effects on externalizing behaviors 3 years later, and childhood family adversity had indirect effects on externalizing behavior through psychological mediators. The findings suggest ways in which family-level adversity poses risk for children's subsequent development of problems at psychological and behavioral levels, situated within diverse cultural contexts.
In this present study, different volume percentages of titanium dioxide nanoparticles were added as dispersions in commercially pure magnesium using the blend-press-sinter powder metallurgy process followed by hot extrusion. The physically blended titanium dioxide nanoparticles dispersoid induced a significant grain refinement in the extruded magnesium matrix. Characterization of the mechanical properties revealed that the increasing volume percentage of titanium oxide nanoparticles dispersion was effective in enhancing the ductility of magnesium without disturbing the strength under tensile loading and enhancing the strength of magnesium without disturbing the ductility under compressive loading. The dominating deformation mechanism in pure magnesium was the dislocation slip, which was subdued by the tensile twinning deformation mechanism due to the increasing presence of titanium dioxide dispersion. The effect of shift in the dominating deformation mechanism was displayed by the elimination of tensile-compressive asymmetry in magnesium when dispersed with 1 vol% of titanium dioxide nanoparticles.
A method comprising a two-step alkali/acid treatment of poly (vinylidene fluoride) (PVDF) polymer is developed for the fabrication of flat-sheet PVDF membranes functionalized with labile hydroxyl groups. This method involves the application of a short-duration modification in alkali medium (5% KOH). Extensive characterizations were performed on the prepared membranes. Modification of the polymer altered the crystallinity of the PVDF from a mixture of both α and β phases to a predominant β phase. Lower work of adhesion of the modified membrane indicated the formation of a more hydrophobic and wetting-resistant membrane surface. Centrifugation of the polymer dope after the modification had a pronounced impact on the properties of the resultant membranes. This protocol could be utilized in fine-tuning the properties of PVDF membranes for various target-specific applications such as membrane distillation. This method can also be used in functionalizing PVDF membranes further by exploiting the labile –OH group present on the membrane surface.
We report on a wide-range Density Functional Theory (DFT) investigation of the g-C3N4 photocatalysis systems combined with metals/nonmetals, especially those available in plants and involved in the natural photosynthesis process, such as K, Mg, Mn, Mo, Fe, Co, Cr, S and B. It is found that doping increases the range at which light absorption occurs to significantly large regions of the visible spectrum. These findings suggested that the g-C3N4 can be a promising system for the photosynthesis process.
This article reports investigation of the effects of high-rate stochastic micro-mechanics on the produced particulate size distribution during ball milling of reactive bimetallic foils (nanoheaters), by experimental and computational modeling. In particular, Ni-Al foils are ball-milled at various load charges, revolution rates and process durations, and the resulting particulate geometries are characterized by micrograph statistical analysis. Numerical simulation of the evolving particulate structure is based on coalescence and fragmentation of flexible monometallic ellipsoidal primitives, impacted by milling balls and vial walls with kinetic theory-based kinematics. Particulates are constrained by discrete compliant and continuum media and undergo conceptual ideal elastic transformations modeled by strain energy methods, and recast into inelastic frictional and plasticity-driven welding and fracture events. Finally the theoretical model predictions of particulate size distribution are validated against laboratory microscopy observations.
Magnesium based nanocomposites containing 0.66 vol% of different types of oxide (i.e., Al2O3, Y2O3, and ZrO2) nano particles. The nano oxide particles were dispersed using melt processing. Microstructural characterization reveled that Y2O3 and ZrO2 nano particles were relatively better magnesium matrix grain refiner compared to nano-size Al2O3 particles. Mechanical characterization revealed that the oxides used in this study as reinforcement have strong strengthening effect on the magnesium matrix, where Y2O3 particles were most effective and Al2O3 particles were least effective. Ductility and resistance to fracture of magnesium was significantly improved by Al2O3 nano particles, unaffected by Y2O3 nano particles, and adversely affected by ZrO2 nano particles.
This study advances understanding of predictors of child abuse and neglect at multiple levels of influence. Mothers, fathers, and children (N = 1,418 families, M age of children = 8.29 years) were interviewed annually in three waves in 13 cultural groups in nine countries (China, Colombia, Italy, Jordan, Kenya, Philippines, Sweden, Thailand, and the United States). Multilevel models were estimated to examine predictors of (a) within-family differences across the three time points, (b) between-family within-culture differences, and (c) between-cultural group differences in mothers' and fathers' reports of corporal punishment and children's reports of their parents' neglect. These analyses addressed to what extent mothers' and fathers' use of corporal punishment and children's perceptions of their parents' neglect were predicted by parents' belief in the necessity of using corporal punishment, parents' perception of the normativeness of corporal punishment in their community, parents' progressive parenting attitudes, parents' endorsement of aggression, parents' education, children's externalizing problems, and children's internalizing problems at each of the three levels. Individual-level predictors (especially child externalizing behaviors) as well as cultural-level predictors (especially normativeness of corporal punishment in the community) predicted corporal punishment and neglect. Findings are framed in an international context that considers how abuse and neglect are defined by the global community and how countries have attempted to prevent abuse and neglect.
The evaluation of quality of life (QoL) among older adults has become increasingly important, and living arrangements play a pivotal role in determining the QoL of people with cognitive impairment (PWCI). Although informal care (home-based) is favored, transition to formal care (residential care) often becomes necessary, especially in the later stages of cognitive impairment. The primary objective was to compare the QoL of PWCI in the community and nursing homes. Additionally, factors differentiate the QoL of PWCI in these two settings were identified.
This is a quasi-experimental study design involving 219 older adults with cognitive impairment, aged 60–89 years old from both nursing home and home care. Participants completed the EUROPE Health Interview Survey-QoL (WHO-8), the Short Mini-Mental State Examination (SMMSE), the Barthel Index (BI), the Geriatric Depression Scale (GDS-15), and the Friendship Scale (FS).
There were significant differences in QoL, depression, social connectedness (p < 0.01) and cognitive functions (p = 0.01) between home care recipients and nursing home participants. No significant differences were observed with regards to health condition, co morbidities and physical functions between study cohorts.
Older adults with cognitive impairment living at home experienced higher QoL, had better cognitive function, were less depressed and reported higher social connectedness compared to those living in institutional care. Therefore, support should be provided in enabling home care and empowering caregivers to provide better care for PWCI.
The study aimed to detail the lifestyle (physical activity and dietary habits) of Moroccan adolescents.
Cross-sectional study undertaken in the framework of the ATLS (Arab Teens Lifestyle Study).
Physical activity and dietary habits were determined using a validated questionnaire in public secondary schools.
A total of 669 adolescents aged 15·0–19·9 years were randomly recruited from Kenitra, Morocco.
Physical activity patterns and intensity differed between genders. As anticipated, male adolescents were more active than female adolescents across a typical week and engaged in more vigorous-intensity physical activity than female adolescents, who spent more time than male adolescents in moderate-intensity physical activity. Of particular concern was that one in five of the adolescents surveyed was inactive, with almost 45 % of the sample reporting television viewing for more than 2 h/d and 38 % engaged in computer use for a similar period. From a dietary perspective, most adolescents reported that they do not take breakfast or consume milk and dairy products, fruits and vegetables on a daily basis. In contrast, most reported consumption of doughnuts, cakes, candy and chocolate more than three times per week and approximately 50 % consumed sugary drinks more than three times per week.
Based on a continuation of the self-reported lifestyle behaviours, adolescents in the present study are at risk of developing chronic diseases. Education programmes are urgently needed to assist in the promotion of a healthy lifestyle and reduce the likelihood of overweight and obesity and related health risks among young people.
Within the World Health Organization 2012–2020 roadmap for control and elimination of schistosomiasis, the scale-up of mass drug administration with praziquantel is set to change the epidemiological landscape across Africa and Arabia. Central in measuring progress is renewed emphasis upon diagnostics which operate at individual, community and environmental levels by assessing reductions in disease, infections and parasite transmission. However, a fundamental tension is revealed between levels for present diagnostic tools, and methods applied in control settings are not necessarily adequate for application in elimination scenarios. Indeed navigating the transition from control to elimination needs careful consideration and planning. In the present context of control, we review current options for diagnosis of schistosomiasis at different levels, highlighting several strengths and weaknesses therein. Future challenges in elimination are raised and we propose that more cost-effective diagnostics and clinical staging algorithms are needed. Using the Kingdom of Saudi Arabia as a contemporary example, embedding new diagnostic methods within the primary care health system is discussed with reference to both urogenital and intestinal schistosomiasis.
We used aquatic macro-invertebrates as a model to investigate the relationship between the regional species richness (RSR) and local species richness (LSR) in Peninsular Malaysia. A total of 38 streams (local scale) in seven catchments (regional scale), were sampled for aquatic macro-invertebrates. Eleven environmental variables (i.e. pH, DO, velocity, temperature, width, depth, TSS, BOD, COD, ammonia and canopy cover) were measured to assess their importance for local species richness. The average species richness was 34.9 species per region and the average abundance was 1380 individual per region. The highest number of species was 41, while the lowest species richness was 31. We applied local-regional richness regression models to explore the nature of the RSR–LSR relationship and then used variation partitioning to determine the relative importance of RSR and environmental conditions on LSR. We found a linear RSR–LSR relationship, which indicates unsaturated communities for macro-invertebrates in Malaysian streams and absence of local control with strong effects of regional processes. Variation in LSR explained by RSR was 43%, while the variation fraction in LSR explained by environmental conditions was low (2%) and not significant. We conclude that the variation in LSR is mainly controlled by the regional diversity pool (i.e. RSR) for aquatic macro-invertebrates in Peninsular Malaysia. However, weak effects of environmental conditions may reflect relatively low variability in the habitat among investigated streams. Further studies at larger scales, and involving different regions in this area, will be useful to draw comprehensive conclusions about determinants of local species diversity for stream invertebrates.
This study examined whether parents’ social information processing was related to their subsequent reports of their harsh discipline. Interviews were conducted with mothers (n = 1,277) and fathers (n = 1,030) of children in 1,297 families in nine countries (China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States), initially when children were 7 to 9 years old and again 1 year later. Structural equation models showed that parents’ positive evaluations of aggressive responses to hypothetical childrearing vignettes at Time 1 predicted parents’ self-reported harsh physical and nonphysical discipline at Time 2. This link was consistent across mothers and fathers, and across the nine countries, providing support for the universality of the link between positive evaluations of harsh discipline and parents’ aggressive behavior toward children. The results suggest that international efforts to eliminate violence toward children could target parents’ beliefs about the acceptability and advisability of using harsh physical and nonphysical forms of discipline.
The red-bed deposits in northern Iraq are situated in an active foreland basin adjacent to the Zagros Orogenic Belt, bound to the north by the Iranian plate thrust over the edge of the Arabian plate. The red-bed successions are composed of alternating red and brown silty mudstones, purplish red calcareous siltstone, fine- to coarse-grained pebbly sandstone and conglomerate. The red beds in the current study can be divided into four parts showing a trend of upward coarsening with fine-grained deposits at the top. A detailed petrographic study was carried out on the sandstone units. The clastic rocks consist mainly of calcite cemented litharenite with rock fragments (volcanic, metamorphic and sedimentary), quartz and minor feldspar. The petrographic components reflect the tectonic system in the source area, laterally ranging from a mixed orogenic and magmatic arc in Mawat–Chwarta area to recycled orogenic material rich in sedimentary rock fragments in the Qandel area. The Cretaceous–Palaeogene foreland basin of northern Iraq formed to the southwest of the Zagros Suture Zone and the Sanandaj–Sirjan Zone of western Iran. During Palaeogene time deposition of the red beds was caused by renewed shortening in the thrust sheets overlying the Arabian margin with uplift of radiolarites (Qulqula Formation), resulting in an influx of radiolarian debris in addition to continuing ophiolitic detritus. Mixed sources, including metamorphic, volcanic and sedimentary terranes, were present during deposition of the upper part of the red beds.
Many adverse environmental factors influencing the Shatt-al Arab River, southern Iraq, during the past century and especially in recent years, combined with the ever-increasing demand for freshwater in the region, indicate the need to obtain information about its salinity regime. The aim of our study was both to find out what historical data there are and then to compare these with the results of a survey of the salinity and water quality of a stretch of the present river over the year October 2009–September 2010. The evidence suggests that there has been a marked upstream shift in the influence of sea water. Salinity values of 2 and 8‰ were found at two sites where elevated salinity had never been reported previously. Water quality variables indicated increased concentrations over the previous four decades and were beyond the national and international standards. As such changes in a major water resource have serious implications for the inhabitants of Basrah, the biological diversity in the river and the whole Gulf ecosystem, it is suggested that there should be a much more detailed study to provide the evidence needed to convince upstream water users of the need to conserve water and manage the whole catchment properly.
National nutrition survey covering all geographical areas of the country.
Kuwaitis (n 1704) between 3 and 86 years of age.
Obesity was more prevalent among women than men (50 % and 70 % for females aged 19–50 years and ≥51 years, respectively, v. 29 % and 42 % for their male counterparts). Boys were more obese than girls, with the highest obesity rate among those aged 9–13 years (37 % and 24 % of males and females, respectively). Energy intake was higher than the estimated energy requirements for almost half of Kuwaiti children and one-third of adults. The Estimated Average Requirement was exceeded by 78–100 % of the recommendation for protein and carbohydrates. More than two-thirds of males aged ≥4 years exceeded the Tolerable Upper Intake Level for Na. Conversely, less than 20 % of Kuwaitis, regardless of age, consumed 100 % or more of the Estimated Average Requirement for vitamin D, vitamin E, Ca, n-3 and n-6 fatty acids. Less than 20 % of children met the recommended level for fibre.
Nutrition transition among Kuwaitis was demonstrated by the increased prevalence of obesity and overweight, increased intakes of energy and macronutrients and decreased intakes of fibre and micronutrients. Interventions to increase awareness about healthy foods combined with modifications in subsidy policies are clearly warranted to increase consumption of low-energy, nutrient-dense foods.
Objective: To estimate the heritability of ambulatory blood pressure (BP), heart rate (HR), and beat-to-beat office BP and HR in an isolated, environmentally and genetically homogeneous Omani Arab population. Methods: Ambulatory BP measurements were recorded in 1,124 subjects with a mean age of 33.8 ± 16.2 years, using the auscultatory mode of the validated Schiller ambulatory BP Monitor. Beat-to-beat BP and HR were recorded by the Task Force Monitor. Heritability was estimated using quantitative genetic analysis. This was achieved by applying the maximum-likelihood-based variance decomposition method implemented in SOLAR software. Results: We detected statistically significant heritability estimates for office beat-to-beat, 24-hour, daytime, and sleep HR of 0.31, 0.21, 0.20, and 0.07, respectively. Heritability estimates in the abovementioned conditions for systolic BP (SBP)/diastolic BP (DBP)/mean BP (MBP) were all significant and estimated at 0.19/0.19/0.19, 0.30/0.44/0.41, 0.28/0.38/0.39, and 0.21/0.18/0.20, respectively. Heritability estimates for 24-hour and daytime ambulatory SBP, DBP, and MBP ranged from 0.28 to 0.44, and were higher than the heritability estimates for beat-to-beat recordings and sleep periods, which were estimated within a narrow range of 0.18–0.21. Conclusion: In this cohort, because shared environments are common to all, the environmental influence that occurs is primarily due to the variation in non-shared environment that is unique to the individual. We demonstrated significant heritability estimates for both beat-to-beat office and ambulatory BP and HR recordings, but 24-hour and daytime ambulatory heritabilities are higher than those from beat-to-beat resting levels and ambulatory night-time recordings.
NbN thin films grown on Nb using pulsed laser deposition (PLD) were investigated for film crystal structures. The nanomechanical properties of NbN on Nb were examined as a function of the film/substrate crystal structure. X-ray diffraction (XRD) reveals peaks that correspond to δ-NbN cubic and β-Nb2N hexagonal phases in addition to δ′-NbN phase. Samples of various crystal structures were tested for phase characterization, microstructure, and surface morphology using XRD analysis, scanning electron microscopy, and atomic force microscopy. The nanomechanical properties were investigated using nanoindentation. The results indicate that there are clear effects of the crystal structure on the hardness of the PLD-grown NbNx films.