Improvements in hydrogen production from methane dry reforming on filament-shaped mesoporous alumina-supported cobalt nanocatalyst

The mesoporous gamma-alumina (γ-Al₂O₃) synthesized via evaporation-induced self-assembly method (EISA) using inorganic salt, Al(NO₃)₃·9H₂O precursor and water-ethanol solvent mixture was implemented as a support for Co catalyst in methane dry reforming at 973–1073 K under 1 atm. The γ-Al₂O₃ support possessed filament-shaped morphology with surface area of 173.4 m² g^?1 and cobalt nanoparticles were successfully dispersed on support with small crystallite size of 7.8 nm. The stability of 10%Co/Al₂O₃ was evident for CH₄ and CO₂ conversions at 1023 and 1073 K. CH₄ conversion could reach to 76.2% while 81.6% was observed for CO₂ conversion at 1073 K. Although graphitic and amorphous carbons were unavoidably formed on used catalyst, 10%Co/Al₂O₃ exhibited an outstanding performance comparable to noble metals with the desired ratio of H₂/CO for downstream Fischer-Tropsch process.     

Evaluation of Three Numerical Weather Prediction Models for Short and Medium Range Agrohydrological Applications

The skill and accuracy of the quantitative precipitation forecasts by CCAM, UM and NCEP-MRF models are verified using various statistical scores at the Mgeni catchment in KwaZulu-Natal, South Africa. The CCAM model is capable of identifying a rainfall event, but with a tendency of under-estimating its magnitude. The UM model is capable of distinguishing rainy days from non-rainy days, but with a significant over-estimation of rainfall amount. There is no significant difference between the 1 and 2 day lead time UM forecasts. Statistical comparisons show that there is an acceptable skill in the CCAM forecasts, but the forecast skill of the UM model is low and unreliable. The role of the initial hydrological conditions in affecting the accuracy of CCAM and UM streamflows forecasts was significant. The results show that the under-estimation of the CCAM forecasts was reduced from −44% to −10%, while the over-estimation in the UM forecasts was reduced from 291% to only 59% when the ACRU agrohydrological model was initialised with observed rainfalls up to the previous day at each forecast run within the study period. The combined use of the CCAM and UM models by a “weighted averaging” had little effect in improving the skill as it is overshadowed more by the over-estimation of the UM forecasts than the under-estimation of the CCAM forecasts. Results obtained for a continuous period of 92 days showed that the NCEP-MRF rainfall forecasts were significantly over-predicted. The NCEP-MRF rainfall forecast is found to be totally unskillful, although the skill was seen to slightly increase with decreasing lead time.     

Local cerebral blood flow measured by xenon-enhanced CT during cryogenic brain edema and intracranial hypertension in monkeys

We developed a closed-skull model of freeze injury-induced brain edema, a model classically thought to produce vasogenic edema, and observed the natural course of changes in edema and blood flow using xenon-enhanced computed tomography (CT) in five rhesus monkeys before and for up to 6 h post insult. Intracranial pressure (ICP) gradually rose throughout the duration of the experiment. CT scans and CBF images permitted direct observation of the evolution of the lesion and revealed early ischemia in the periphery of the injury zone that progressed over time in association with edema. Frequency histogram analysis of local CBF (ICBF) demonstrated subtle but potentially important changes in distribution of ICBF between and within hemispheres at various times post insult. Changes in ICBF distribution were phasic and dissociated from increases in ICP in the latter stages of injury. The Xe/CT CBF method can be used to evaluate the effects of injury and therapy on CBF in this and other models of acute brain injury.     

埃塞俄比亚金属矿产资源综述

在大量查阅、深刻分析国内外中英文文献以及实地野外调查踏勘的基础上,对埃塞俄比亚国家的金属矿产资源进行了较为详细地概述。研究表明,该国金属矿产资源主要分布在西部、北部和南部绿岩带。从前寒武纪到近代构造构成了埃塞俄比亚地质学的基础。其中低级变质火山沉积岩组合赋存了绝大多数经济矿床,包括金、铂族元素、镍、贱金属（Cu、Pb、Zn）、磷酸盐、铁等,并且其中生代沉积岩含有天然燃料矿产和一些金属矿产如孔雀石、锰矿石和含石膏矿物。分析发现埃塞俄比亚金属矿产资源具有良好的开采和开发前景,特别是金、铂等贵金属,镍等黑色金属,铜等有色金属,铌、钽等稀有金属,铀（钍）等放射性金属。     

Room temperature synthesis of metal organic framework MOF-2

One of the pioneering metal organic framework material, called MOF-2 and having the formula [Zn₂(BDC)₂], still continues awakening interest amongst the scientific community in spite of its layered character. However, the synthesis methods are either experimentally complicated or in two steps through the transformation of MOF-1. Here, we describe the preparation of a high-quality MOF-2 under more sustainable conditions, including room temperature, absence of any amine or any other pH-controller, partial substitution of the harmful organic solvent (N,N-dimethylformamide) by water, and by simply mixing linker and metal sources, the latter being zinc acetate, carefully selected as a function of their solubility in the solvent mixture. The optimum ratio of Zn(OAc)₂·4H₂O to terephthalic acid (H₂BDC) is 1.74 and H₂O to DMF is 3. MOF-2 [Zn₂(BDC)₂] has been characterized using powder X-ray diffraction, thermogravimetric analysis, N₂ adsorption/desorption and scanning electron microscopy, all of them supporting the good quality of the material.     

A Fuzzy-Stochastic Modeling Approach for Multiple Criteria Decision Analysis of Coupled Groundwater-Agricultural Systems

The complexity of water resources management increases when decisions about environmental and social issues are considered in addition to economic efficiency. Such complexities are further compounded by multiple uncertainties about the consequences of potential management decisions. In this paper, a new fuzzy-stochastic multiple criteria decision-making approach is proposed for water resources management in which a variety of criteria in terms of economic, environmental and social dimensions are identified and taken into account. The goal is to evaluate multiple conflicting criteria under uncertainties and to rank a set of management alternatives. The methodology uses a simulation-optimization water management model of a strongly interacting groundwater-agriculture system to enumerate criteria based on these bio-physical process interactions. Fuzzy and/or qualitative information regarding the decision-making process for which quantitative data is not available are evaluated in linguistic terms. Afterwards, Monte Carlo simulation is applied to combine these information and to generate a probabilistic decision matrix of management alternatives versus criteria in an uncertain environment. Based on this outcome, total performance values of the management alternatives are calculated using ordered weighted averaging. The proposed approach is applied to a real world example, where excessive groundwater withdrawal from the coastal aquifer for irrigated agriculture has resulted in saltwater intrusion, threatening the economical basis of farmers and associated societal impacts. The analysis has provided potential decision alternatives which can serve as a platform for negotiation and further exploration. Furthermore, sensitivity of different inputs to resulting rankings is investigated. It is found that decision makers’ risk aversion and risk taking attitude may yield different rankings. The presented approach suits to systematically quantify both probabilistic and fuzzy uncertainties associated with complex hydrosystems management.     

Epidemiological game-theory dynamics of chickenpox vaccination in the USA and Israel

The general consensus from epidemiological game-theory studies is that vaccination coverage driven by self-interest (Nash vaccination) is generally lower than group-optimal coverage (utilitarian vaccination). However, diseases that become more severe with age, such as chickenpox, pose an exception to this general consensus. An individual choice to be vaccinated against chickenpox has the potential to harm those not vaccinated by increasing the average age at infection and thus the severity of infection as well as those already vaccinated by increasing the probability of breakthrough infection. To investigate the effects of these externalities on the relationship between Nash and utilitarian vaccination coverages for chickenpox, we developed a game-theory epidemic model that we apply to the USA and Israel, which has different vaccination programmes, vaccination and treatment costs, as well as vaccination coverage levels. We find that the increase in chickenpox severity with age can reverse the typical relationship between utilitarian and Nash vaccination coverages in both the USA and Israel. Our model suggests that to obtain herd immunity of chickenpox vaccination, subsidies or external regulation should be used if vaccination costs are high. By contrast, for low vaccination costs, improving awareness of the vaccine and the potential cost of chickenpox infection is crucial.     

The xenon-enhanced computed tomography cerebral blood flow method

It has been proposed that one of the primary events in the development of essential hypertension is a growth-related process initiated as early as during fetal development. Differences in kidney size have been observed between most rat models of hypertension and their respective controls. In this study, we analyzed relative kidney size (kidney weight/body wt) in a set of rat recombinant inbred strains (RIS) (N = 27) and their progenitors, the spontaneously hypertensive rat strain (SHR/Ola) and Brown Norway congenic strain (BN.1x), at two different ages, at birth and at 15 weeks. In the progenitors, the relative kidney weight was higher in the hypertensive than in the normotensive strain of both the newborn (P < 0.001) and adult (P < 0.001) animals. In the RIS, a significant correlation was found between the newborn and adult relative kidney weight (r = 0.49, P = 0.01), indicating that the two phenotypes share some of their genetic determinants. A total genome search of newborn and adult relative kidney weight was performed with a total of 453 genetic markers. These analyses revealed several suggestive quantitative trait loci (QTL), some of which were, indeed, significant for both newborn and adult relative kidney weight (such as, D3Mit9 on rat chromosome 3; r = -0.50, P < 0.01; r = -0.47, P < 0.01; respectively). Others, such as the locus on rat chromosome 1 (Rt6; r = -0.43, P < 0.05), were significant only for the adult relative kidney size. This QTL was found in close proximity to a region previously related to susceptibility to hypertensive renal disease in the fawn-hooded rat and, similarly to that study, its effect was found to be independent of blood pressure. Furthermore, a growth pattern of the kidneys after birth, evaluated as the difference between the newborn and adult relative kidney weight, was also subjected to total genome scan. Several suggestive QTL were identified. One of the most significant loci was found at the D1a marker on rat chromosome 17 (r = -0.51, P < 0.01), which was previously related to the determination of adult heart weight in the RIS. In conclusion, the current study demonstrates the usefulness of RIS in studies of hypertension-related phenotypes, some of which are abnormal before the development of high blood pressure. To better understand their role in the pathogenesis of hypertension, studies at different ages are needed, which are uniquely feasible in RIS.     

Inventory of plants used in traditional medicine in Somalia. II. Plants of the families Combretaceae to Labiatae

Fifty-nine plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.