Storing Electricity in a Country's Electrical Grid as a Key Energy Problem of the 21st Century

Basic problems of optimizing the structure of a country's electrical grid by incorporating storage facilities and renewable sources of energy into the grid are formulated, and the authors' vision on how to approach some of these problems is offered. A game model for analyzing the potential of an electrical grid with storing facilities to serve its customers and for finding fair (equilibrium) electricity tariffs in it is discussed, and an elementary scheme for estimating advantages of using these fair tariffs by a customer of the grid is proposed. Keywords: derivatives; electrical grid; storing electricity; storing strateg

Acute military psychiatric casualties from the war in Iraq

Background: The view that most military personnel evacuated from war zones are suffering from combat stress reactions, or are otherwise traumatised by the horrors of war, has an impact on all aspects of military psychiatry. Aims: To delineate the reasons for psychiatric aeromedical evacuation from Iraq from the start of build-up of UK forces in January 2003 until the end of October that year, 6 months after the end of formal hostilities. Method: A retrospective study was conducted of field and in-patient psychiatric assessments of 116 military personnel evacuated to the UK military psychiatric in-patient facility in Catterick Garrison. Results: Evacuees were mainly non-combatants (69%). A significant proportion were in reserve service (21%) and had a history of contact with mental health services (37%). Only 3% had a combat stress reaction. In over 85% of cases evacuation was for low mood attributed to separation from friends or family, or difficulties adjusting to the environment. Conclusions: These findings have implications especially for screening for suitability for deployment, and for understanding any longer-term mental health problems arising in veterans from Iraq

Evaluating Use of Custom Survey Reports by Local Health Departments

This report demonstrates how providing survey feedback, like comparative reports, to survey respondents can result in improvement activities. For each of the past three years (2010-2013), the North Carolina Institute for Public Health (NCIPH) has invited local health departments (LHDs) from 40 states to participate in a preparedness capacities survey. In addition, NCIPH fielded a six-question evaluation survey to a subset of LHDs (n=70) to determine how LHDs use these reports. LHDs that reported using their custom reports compared their preparedness capacities to other LHDs, conducted strategic planning (e.g., benchmarking, setting preparedness goals), planned staff trainings, and disseminated the report both internally and to external preparedness partners. Through evaluation of custom report use, we have found that survey feedback is a valuable part of a participatory research approach that promotes and encourages discussion, motivates improvement, and provides opportunities to identify potential solutions relevant to both researchers and LHDs

Nrt1 and Tna1-Independent Export of NAD+ Precursor Vitamins Promotes NAD+ Homeostasis and Allows Engineering of Vitamin Production

NAD+ is both a co-enzyme for hydride transfer enzymes and a substrate of sirtuins and other NAD+ consuming enzymes. NAD+ biosynthesis is required for two different regimens that extend lifespan in yeast. NAD+ is synthesized from tryptophan and the three vitamin precursors of NAD+: nicotinic acid, nicotinamide and nicotinamide riboside. Supplementation of yeast cells with NAD+ precursors increases intracellular NAD+ levels and extends replicative lifespan. Here we show that both nicotinamide riboside and nicotinic acid are not only vitamins but are also exported metabolites. We found that the deletion of the nicotinamide riboside transporter, Nrt1, leads to increased export of nicotinamide riboside. This discovery was exploited to engineer a strain to produce high levels of extracellular nicotinamide riboside, which was recovered in purified form. We further demonstrate that extracellular nicotinamide is readily converted to extracellular nicotinic acid in a manner that requires intracellular nicotinamidase activity. Like nicotinamide riboside, export of nicotinic acid is elevated by the deletion of the nicotinic acid transporter, Tna1. The data indicate that NAD+ metabolism has a critical extracellular element in the yeast system and suggest that cells regulate intracellular NAD+ metabolism by balancing import and export of NAD+ precursor vitamins

Gell-Mann--Okubo Mass Formula for an SU(4) Meson Hexadecuplet

Using a linear mass spectrum of an $SU(4)$ meson hexadecuplet, we derive the Gell-Mann--Okubo mass formula for the charmed mesons, in good agreement with experiment. Possible generalization of this method to a higher symmetry group is briefly discussed.Comment: 11 pages, LaTe

Decoherence and energy loss in QCD cascades in nuclear collisions

The medium modifications in the properties of QCD cascades are considered. In particular, the changes in the intrajet rapidity distributions due to medium-induced decoherence, collisional losses of cascade gluons and those of final prehadrons are analyzed

Role of hepcidin in the development of anemia in patients with rheumatoid arthritis

Chronic disease anemia (CDA) diagnosed in many patients with rheumatoid arthritis (RA) was described in the early 1970s. As earlier noted, iron metabolic disturbances in CDA are its diagnostic feature and the discovery of hepcidin, an iron-regulatory acute-phase protein, could largely clarify an association between the immune mechanism of impaired iron homeostasis and the development of CDA. Objective: to define the role of hepcidin in the differential diagnosis of CDA and true iron deficiency in patients with RA. Subjects and methods. The investigation enrolled 76 patients with RA (1987 ACR criteria) admitted to the Research Institute of Rheumatology, Russian Academy of Medical Sciences, to be treated. The patients were divided into two groups. A study group comprised anemic patients (n = 47). The WHO criteria for anemia were considered to be hemoglobin (Hb) levels of below 120 g/l for women and below 130 g/l for men. A control group consisted of non-anemic patients (n = 29). The anemic and non-anemic patients were matched for age (45.5±14.3 and 49.8±14.3 years, respectively) and disease duration (2 months to 20 years) (p > 0.05). Iron metabolic parameters, such as serum iron, total serum iron-binding capacity (TSIBC), iron transferrin saturation (ITS), transferrin receptors, and serum ferritin (SF), were studied and the level of hepcidin prohormone was estimated by direct enzyme immunoassay (Hepcidin Prohormone Enzyme Immunoassay Kit, IBL, Germany) in all the patients to be analyzed. Cytokines, such as interleukin 6, tumor necrosis factor-а) were determined by enzyme immunoassay (Bender MedSystems, Austria). The Institute’s differential diagnostic algorithm involving SF, TSIBC, and ITS was used to diagnose iron deficiency. The diagnosis was based on two stages of estimating iron values: isolated iron-deficiency anemia (IDA) was diagnosed if SF was below the normal value (< 40 μg/l). If the patient had SF of μ40 μg/l with a simultaneous rise of TSIBC above the normal level (> 70 μg/l) and a drop of ITS (> 20%), he/she might be suspected as having the mixed genesis of anemia, in which both iron deficiency and CDA are detectable. The other patients could be diagnosed as having isolated CDA. Results. The study has established that irrespective of the hemoglobin level, the content of serum hepcidin prohormone in the examined patients with RA averaged 89.2±65.1 pg/ml and was much higher than that in donors (64.9+21.6 pg/ml; р < 0.05). An analysis of the blood biochemical parameters characterizing iron metabolism showed that, whether they were anemic or non-anemic, the patients with RA, as compared with donors, were found to have an elevated level of SF that is an acute-phase indicator and reflects the high activity of an inflammatory process. To rule out IDA, the anemic patients with RA were subdivided into 3 subgroups according to the differential diagnostic algorithm. Subgroup 1 included patients with isolated CDA (n = 13 patients (28% of those in the study group)); Subgroup 2 consisted of 17 (32%) patients with anemia of mixed genesis (CDA ± IDA), and Subgroup 3 comprised 17 patients with IDA. An analysis of the clinical and laboratory parameters in RA independent of the nature of anemia demonstrated that only the patients with isolated CDA had significantly higher mean values of hepcidin prohormone (120.3±56.1 pg/ml) as compared to the control group (90.3±37.9 pg/ml) and RA patients with iron deficiency (both isolated IDA and that of mixed genesis). The same subgroup had a higher inflammatory RA activity characterized by the highest values of DAS 28, C-reactive protein, and SF. Conclusion. Hepcidin is a negative regulator of iron metabolism and may be used for the differential diagnosis of CDA and true iron deficiency in patients with RA

Effect of Growth Interruption on Surface Recombination Velocity in GaInAsSb/AlGaAsSb Heterostructures Grown by Organometallic Vapor Phase Epitaxy

The effects of growth interruption on the quality of GaInAsSb/AlGaAsSb heterostructures grown by organometallic vapor phase epitaxy are reported. In-situ reflectance monitoring and ex-situ characterization by high-resolution x-ray diffraction, 4K photoluminescence (PL), and time-resolved PL indicate that GaInAsSb is extremely sensitive to growth interruption time as well as the ambient atmosphere during interruption. By optimizing the interruption sequence, surface recombination velocity as low as 20 cm/s was achieved for GaInAsSb/AlGaAsSb double heterostructures

Very high upper critical fields in MgB2 produced by selective tuning of impurity scattering

We report a significant enhancement of the upper critical field $H_{c2}$ of different $MgB_2$ samples alloyed with nonmagnetic impurities. By studying films and bulk polycrystals with different resistivities $\rho$, we show a clear trend of $H_{c2}$ increase as $\rho$ increases. One particular high resistivity film had zero-temperature $H_{c2}(0)$ well above the $H_{c2}$ values of competing non-cuprate superconductors such as $Nb_3Sn$ and Nb-Ti. Our high-field transport measurements give record values $H_{c2}^\perp (0) \approx 34T$ and $H_{c2}\|(0) \approx 49 T$ for high resistivity films and $H_{c2}(0)\approx 29 T$ for untextured bulk polycrystals. The highest $H_{c2}$ film also exhibits a significant upward curvature of $H_{c2}(T)$, and temperature dependence of the anisotropy parameter $\gamma(T) = H_{c2}\|/ H_{c2}^\perp$ opposite to that of single crystals: $\gamma(T)$ decreases as the temperature decreases, from $\gamma(T_c) \approx 2$ to $\gamma(0) \approx 1.5$. This remarkable $H_{c2}$ enhancement and its anomalous temperature dependence are a consequence of the two-gap superconductivity in $MgB_2$, which offers special opportunities for further $H_{c2}$ increase by tuning of the impurity scattering by selective alloying on Mg and B sites. Our experimental results can be explained by a theory of two-gap superconductivity in the dirty limit. The very high values of $H_{c2}(T)$ observed suggest that $MgB_2$ can be made into a versatile, competitive high-field superconductor.Comment: An updated version of the paper (12/12/2002)that was placed on cond-mat on May 7 200

EXPERIMENTAL AND THEORETICAL VALIDATION OF DOUBLE COLUMN INTERNAL FIXATION THEORY FOR DISTAL FEMORAL FRACTURES

Purpose of the study – to experimentally compare efficiency of lateral and bilateral (lateral and medial) plate fixation of distal femoral fractures and to validate the appropriateness of double column theory of distal femur anatomy for internal fixation for these fractures.Material and methods. The authors performed a biomechanical study in two series on polyurethane models of right femur corresponding in dimensions to natural femur. After simulating a 33 C2 fracture type it was fixed by one lateral plate or two (lateral and medial) plates. After fixation the models were tested in six load ranges with maximal load from 20 to 120 kgf in cyclic mode.Results. The authors obtained a significant difference in absolute values of fragments displacement amplitude depending on fixation method. In the first series of the experiment – one plate fixed on the lateral surface of the femur – under minimal load the displacement value was reported as0.3 mm and under maximal load —1.9 mm; in the second series of experiment – two plates fixed on the lateral and medial surfaces of the femur – displacement values were reported as0.35 mm and0.95 mm respectively. Conclusion. The presence or absence of medial support after internal fixation has a profound impact on ensuring stability in cases of comminuted fractures of distal femoral fractures. In this context the use of double column theory of distal femur anatomy for internal fixation can significantly improve the treatment outcomes for such patients. After trials of minimally invasive fixation method on anatomical specimen the described theory can be implemented into the clinical practice