Effect of stress on choline acetyltransferase activity of the brain and the adrenal of the rat.

Choline acetyltransferase (ChAT) activity was determined in cerebral cortex, hypothalamus, hippocampus, cerebellum, medulla oblongata, midbrain and adrenal gland of rats exposed to acute or chronic stress. The exposure of animals to acute immobilization and cold stress (4 degrees C) for one hour resulted in a significant decline of ChAT activity in all brain regions examined except for the medulla oblongata. Moreover, the exposure to acute stress resulted in significant increase of the same enzyme in the adrenal gland. However, chronic exposure of animals to cold stress (4 degrees C) for 7 days resulted in no significant changes of ChAT activity in all tissues examined except for a decline in the midbrain and an increase in the medulla oblongata. The administration of corticosterone (2.0 mg/kg) 1 h prior to sacrificing caused an effect similar to that of acute stress on ChAT activity in all brain regions except for the hypothalamus and the cerebellum. It was concluded from this experiment that stress-induced changes in the ChAT activity of specific brain regions might be mediated by the adrenal steroids.     

SAP is required for generating long-term humoral immunity

Long-lived plasma cells and memory B cells are the primary cellular components of long-term humoral immunity and as such are vitally important for the protection afforded by most vaccines. The SAP gene has been identified as the genetic locus responsible for X-linked lymphoproliferative disease, a fatal immunodeficiency. Mutations in SAP have also been identified in some cases of severe common variable immunodeficiency disease. The underlying cellular basis of this genetic disorder remains unclear. We have used a SAP knockout mouse model system to explore the role of SAP in immune responses. Here we report that mice lacking expression of SAP generate strong acute IgG antibody responses after viral infection, but show a near complete absence of virus-specific long-lived plasma cells and memory B cells, despite the presence of virus-specific memory CD4+ T cells. Adoptive transfer experiments show that SAP-deficient B cells are normal and the defect is in CD4+ T cells. Thus, SAP has a crucial role in CD4+ T-cell function: it is essential for late B-cell help and the development of long-term humoral immunity but is not required for early B-cell help and class switching.     

Estimation of Cloud Node Acquisition Waseem Ahmed and Yongwei Wu简

Over the past decade, there has been a paradigm shift leading consumers and enterprises to the adoption of cloud computing services. Even though most cases are still in the early stages of transition, there has been a steady increase in the implementation of the pay-as-you-go or pay-as-you-grow models offered by cloud providers. Whether applied as an extension of virtual infrastructure, software, or platform as a service, many users are still challenged by the estimation of adequate resource allocation and the wide variations in pricing. Customers require a simple method of predicting future demand in terms of the number of nodes to be allocated in the cloud environment. In this paper, we review and discuss existing methodologies for estimating the demand for cloud nodes and their corresponding pricing policies. Based on our review, we propose a novel approach using the Hidden Markov Model to estimate the acquisition of cloud nodes.     

Ovarian LDH activity in gonadotropin-treated immature rats

Summary Lactate dehydrogenase (LDH) activity was studied in the ovaries of immature rats treated with pregnant mare serum gonadotropin (PMS). LDH activity increased sharply at 36 h after PMS injection in the ovarian tissue as well as in the blood. It was suggested that the increase of LDH activity in the ovary may be related to its increasing ability to secret estrogen.     

Impact of conflict on demographic factors and their importance in negotiated settlement in southern Africa

"Though the concept of negotiated settlements gained its momentum in southern Africa--Angola, Mozambique, Namibia and South Africa--the full success of negotiations is yet to be seen in most of these countries.... Demographic consequences of conflicts are explained through a systemic model. The importance of demographic variables on negotiated settlement has also been explained the same way. There is no easy way out to overcome conflicts...but it is suggested that mutual consultation with opposition parties or minorities, or the suppressed people, would help ease many situations in Africa or elsewhere."     

The Effect of Worker Learning on Scheduling Jobs in a Hybrid Flow Shop: A Bi-Objective Approach

This paper studies learning effect as a resource utilization technique that can model improvement in worker’s ability as a result of repeating similar tasks. By considering learning of workers while performing setup times, a schedule can be determined to place jobs that share similar tools and fixtures next to each other. The purpose of this paper is to schedule a set of jobs in a hybrid flow shop (HFS) environment with learning effect while minimizing two objectives that are in conflict: namely maximum completion time (makespan) and total tardiness. Minimizing makespan is desirable from an internal efficiency viewpoint, but may result in individual jobs being scheduled past their due date, causing customer dissatisfaction and penalty costs. A bi-objective mixed integer programming model is developed, and the complexity of the developed bi-objective model is compared against the bi-criteria one through numerical examples. The effect of worker learning on the structure of assigned jobs to machines and their sequences is analyzed. Two solution methods based on the hybrid water flow like algorithm and non-dominated sorting and ranking concepts are proposed to solve the problem. The quality of the approximated sets of Pareto solutions is evaluated using several performance criteria. The results show that the proposed algorithms with learning effect perform well in reducing setup times and eliminate the need for setups itself through proper scheduling.     

The family Leucospidae (Hymenoptera: Chalcidoidea) from the South of Saudi Arabia,with the first report of the genus Micrapion and description of Leucospis arabica sp. nov.

The family Leucospidae (Hymenoptera: Chalcidoidea) from Saudi Arabia is reviewed. Specimens were mainly collected from the south-western region of the country – Raydah (Abha, Asir), Sajid (Farasan Islands, Jazan) and Wadi Tourabah (Mandaq, Al Baha); and from Egypt – Wadi Khoshb (Sinai Peninsula), as well as a specimen (Leucospis elegans Klug) deposited in the Efflatoun Bey collection, Cairo University, Egypt. The genus Micrapion Kriechbaumer is here recorded for the first time from the fauna of the Arabian Peninsula, with a single species, M. clavaforme. Leucospis arabica Gadallah and Soliman sp. nov. (dorsigera group) is described. Leucospis africana (elegans group) is also newly recorded from the Saudi Arabian fauna, in addition to L. elegans which has been previously recorded. An illustrated key and a list of all leucospid species recorded and expected to occur in Saudi Arabia are provided.

www.zoobank.org/lsid:Zoobank.org:pub:40BEF37F-0D92-4AEF-9990-30C1CFC3A7A7     

Catalytic performance of nano-hybrid graphene and titanium dioxide modified cathodes fabricated with facile and green technique in microbial fuel cell

Finite resources of the world''s fossil fuel give rise to the irresistible urge to explore alternative renewable energy routes such as microbial fuel cells (MFCs). The limited productivity is one of the main obstacles for MFC scalability. In this study, a dual-chamber MFC was assembled and equipped with fabricated modified cathodes with titanium dioxide (TiO2) or hybrid graphene (HG) which mainly improved the catalytic activity of the cathode. The graphite paste (GP) bare electrode was modified by both nanomaterials using a green and facile technique. The results showed that the modified cathodes resulted in a considerable improvement for the MFC performance, i.e., the power density reaching levels of 80 mW/m2 for GP-TiO2 and 220 mW/m2 for GP-HG compared to 30 mW/m2 for GP electrode. Additionally, the modified electrodes exhibited lower charge transfer resistance (Rct) compared to the bare electrode. Therefore, these modified electrodes, fabricated by an eco-friendly method, could be used as alternatives to the precious expensive metals like Pt.     

Dating of monazite-apatite-allanite-epidote corona from the Bayan Obo Group in the northern margin of the North China Craton:implications for the time of regional Au and REE mineralization

The Mesoproterozoic Bayan Obo Group located along the northern margin of the North China Craton (NMNCC) hosts a world's largest known rare-earth element (REE) d...