Polymerization techniques depending on single-electron transfer are explored. The history of such methods, mechanics, and their current deployment are discussed.
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IJS, KILJ, NUK, PNG, UL, UM
Early social isolation results in adult behavioral and cognitive dysfunction that correlates with white matter alterations. However, how social deprivation influences myelination and the significance ...of these myelin defects in the adult remained undefined. We show that mice isolated for 2 weeks immediately after weaning have alterations in prefrontal cortex function and myelination that do not recover with reintroduction into a social environment. These alterations, which occur only during this critical period, are phenocopied by loss of oligodendrocyte ErbB3 receptors, and social isolation leads to reduced expression of the ErbB3 ligand neuregulin-1. These findings indicate that social experience regulates prefrontal cortex myelination through neuregulin-1/ErbB3 signaling and that this is essential for normal cognitive function, thus providing a cellular and molecular context to understand the consequences of social isolation.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Children have served as soldiers throughout history. They fought in the American Revolution, the Civil War, and in both world wars. They served as uniformed soldiers, camouflaged insurgents, and even ...suicide bombers. Indeed, the first U.S. soldier to be killed by hostile fire in the Afghanistan war was shot in ambush by a fourteen-year-old boy.Does this mean that child soldiers are aggressors? Or are they victims? It is a difficult question with no obvious answer, yet in recent years the acceptable answer among humanitarian organizations and contemporary scholars has been resoundingly the latter. These children are most often seen as especially hideous examples of adult criminal exploitation.In this provocative book, David M. Rosen argues that this response vastly oversimplifies the child soldier problem. Drawing on three dramatic examples-from Sierra Leone, Palestine, and Eastern Europe during the Holocaust-Rosen vividly illustrates this controversial view. In each case, he shows that children are not always passive victims, but often make the rational decision that not fighting is worse than fighting.With a critical eye to international law, Armies of the Young urges readers to reconsider the situation of child combatants in light of circumstance and history before adopting uninformed child protectionist views. In the process, Rosen paints a memorable and unsettling picture of the role of children in international conflicts.
The investigation and study of cancer stem cells (CSCs) have received enormous attention over the past 5 to 10 years but remain topics of considerable controversy. Opinions about the validity of the ...CSC hypothesis, the biological properties of CSCs, and the relevance of CSCs to cancer therapy differ widely. In the following commentary, we discuss the nature of the debate, the parameters by which CSCs can or cannot be defined, and the identification of new potential therapeutic targets elucidated by considering cancer as a problem in stem cell biology.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
•A gas turbine combined cycle with gasified biomass external firing is analyzed.•Thermodynamic analysis considers first and second law analyses.•Thermal efficiency peaks at an optimum cycle pressure ...ratio (about 9).•Three sets of operating parameters are considered in a detailed case study.•One of three cases is more efficient from first or second law viewpoints.
Thermodynamic analyses of an externally fired gas turbine combined cycle integrated with a biomass gasification plant, using energy and exergy approaches, are reported for a proposed configuration. Paper is taken to be the fuel and the thermodynamic performance and sizing of the plant is examined for various values of cycle pressure ratio (7–12), gas turbine inlet temperature (1200–1400K) and heat exchanger cold-end temperature difference (245–275K). Depending on the gas turbine inlet temperature and heat exchanger cold-end temperature difference, the system overall energy efficiency is observed to attain a maximum at a particular pressure ratio. For a given pressure ratio, the energy efficiency increases with gas turbine inlet temperature and decreases with heat exchanger cold-end temperature difference. An increase in pressure ratio results in a decrease of air flow rate and an increase of steam flow rates. These flow rates are attributable to the size of combined cycle plant. Raising the gas turbine inlet temperature reduces the air flow rate. The performance of a 1MW plant is investigated with various operating parameters to obtain component ratings and biomass feed rates. Exergy efficiencies of cycle components are examined along with the major thermodynamic irreversibilities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK
A pack level passive thermal management system has been designed, developed and experimentally investigated using a phase change composite material. Three 20Ah capacity LiFePO4 prismatic cells ...connected in series are used to form the battery pack and phase change composite material of different thicknesses are tested. The battery pack has been charged at 1C and discharged at 1C, 2C, 3C and 4C. A total of 18 thermocouples are used to measure the temperature at the principal surface of all three cells. The results obtained with the phase change composite material are compared with no cooling and liquid cooling options. The results show that, with the use of 6mm thick phase change composite material plates, the battery surface temperature reduces from 56.5°C at no cooling to 36.5°C at a 4C discharge rate. Even at a 1C discharge rate, the temperature of the battery pack drops from 33.5°C with no cooling to 29.1°C with phase change material plates. It is also observed that the effect of an increase in phase change material thickness on the battery pack temperature is insignificant beyond a 6mm thick plate. The results show that the temperature gradient is significantly lower with phase change composite material compared to no cooling and liquid cooling.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
An exergoeconomic analysis is reported for a combined system with a net electrical output of 299 MW in which waste heat from a Gas Turbine-Modular Helium Reactor (GT-MHR) is utilized by two Organic ...Rankine Cycles (ORCs). A parametric study is also done to reveal the effects on the exergoeconomic performance of the combined system of such significant parameters as compressor pressure ratio, turbine inlet temperature, temperatures of evaporators, pinch point temperature difference in the evaporators and degree of superheat at the ORC (Organic Rankine Cycle) turbines inlet. Finally the combined cycle performance is optimized from the viewpoint of exergoeconomics. The results show that the precooler, the intercooler and the ORC condensers exhibit the worst exergoeconomic performance. For the overall system, the exergoeconomic factor, the capital cost rate and the exergy destruction cost rate are determined to be 37.95%, 6876 $/h and 11,242 $/h, respectively. Also, it is observed that the unit cost of electricity produced by the GT-MHR turbine increases with increasing GT-MHR turbine inlet temperature but decreases as the other above mentioned parameters increase.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
22q11.2 deletion carriers show specific cognitive deficits, and ∼30% of them develop schizophrenia. One of the disrupted genes is ZDHHC8, which encodes for a palmitoyltransferase. We show that ...Zdhhc8-deficient mice have reduced palmitoylation of proteins that regulate axonal growth and branching. Analysis of axonal projections of pyramidal neurons from both Zdhhc8-deficient and Df(16)A(+/-) mice, which model the 22q11.2 deletion, revealed deficits in axonal growth and terminal arborization, which can be prevented by reintroduction of active ZDHHC8 protein. Impaired terminal arborization is accompanied by a reduction in the strength of synaptic connections and altered functional connectivity and working memory. The effect of ZDHHC8 is mediated in part via Cdc42-dependent modulation of Akt/Gsk3β signaling at the tip of the axon and can be reversed by pharmacologically decreasing Gsk3β activity during postnatal brain development. Our findings provide valuable mechanistic insights into the cognitive and psychiatric symptoms associated with a schizophrenia-predisposing mutation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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