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Samarium substituted ceria has been studied as a potential electrolyte material for intermediate temperature range solid oxide fuel cells. The structural, microstructural, morphological and electrochemical properties of the Ce1−xSmxO2−δsolid electrolytes were analyzed, with different substitutions from 0.05 to 0.50. The difference in the ionic radii of Sm3+and Ce4+resulted in lattice strain and expansion, which was found to decrease the average size of crystallites. The ionic conductivity of ceria increases as Sm3+concentration is increased upto a limit of 20%. This is due to the combination of vacancy-vacancy repulsion and vacancy trapping by the substitution at a higher level. However, the conductivity of Ce0.80Sm0.20O2−δwas the highest, at 4.04 × 10−2S cm−1at 600 °C. The grain activation energy and grain boundary activation energy were also found to be ∼0.87 eV and ∼0.74 eV respectively. The low values of activation energies indicate that Ce0.80Sm0.20O2−δcould be a suitable electrolyte material for intermediate-temperature solid oxide fuel cells.

Thermal management is critical for the safety of electric vehicle (EV) battery packs, especially under ultra-fast and extreme fast charging and discharging use conditions. Liquid cooling is particularly attractive over other battery thermal management technologies due to its high heat transfer coefficient and low power usage. This paper systematically studies a liquid-cooled battery thermal management system for limiting the maximum temperature and voltage excursions of a standard 18650 lithium-ion battery pack. Considering two different coolant flow configurations, the influences of coolant flow rate, inlet temperature, battery capacity, charge rate, and discharge rate are investigated through a detailed computational study. Based on the simulations, design windows are developed for keeping the maximum temperature during charging below 45 °C and during discharging within 60 °C, as well as maintaining the cell voltage < 4.2 V. The design windows provide the maximum charge and discharge rates that can be achieved with a given coolant flow rate and inlet temperature for a battery capacity. Equivalently, the design windows may be utilized for a desired charge and discharge rate to obtain the required coolant flow design. The study provides valuable insight into advancing the ultra and extreme fast charge and discharge capabilities of battery packs for EV applications.

Considering the increasing gap between energy demand and clean energy supply availability, there is a strong need to impart novel design structures to effectively utilize the available resources and energy storage systems. Nature-inspired fin structures embedded with well-chosen phase change materials (PCM) can play an essential role in improving the heat transfer in thermal energy storage devices. The present work investigates the melting and solidification processes in a metallic heat exchanger filled with n-octadecane as working PCM, with tree-shaped fins. The study is conducted for various fin generation numbers, volume fractions, length ratios, and angles between the Y-shaped tree fin branches. The results are discussed in the form of melt fraction of PCM, heated surface average temperature variation, and thermal energy stored. The results clearly indicate that the heat transfer is significantly improved with increasing branches of the tree-structured fins because of an increased area available for heat transfer. This study can be utilized to enhance the performance of PCM embedded thermal energy storage devices.

Radiation hormesis is the stimulatory or beneficial effect of low doses of ionising radiation. Data from animal experiments and human experiences suggest common mechanisms of the protective role of hormesis in radiation induced cancer. Through various studies, it is established that whole body exposure to low-level ionising radiation (LLIR) decreases overall cancer incidence (the most important long-term somatic effect of radiation exposure). In this paper, a comprehensive study and analyses of the available historical and scientific data and reports (both laboratory and epidemiological), that relate to LLIR are summarised and presented. This leads to the substantially acceptable conclusion that whole body exposure to LLIR reduces cancer mortality rates when compared with control populations in both experimental animals and humans.

Background: Gulf war veterans report more symptomatic ill-health than other military controls, and skin disease is one of the most frequent reasons for military personnel to seek medical care.
Aim: To compare the nature and prevalence of skin disease in UK Gulf veterans with non-Gulf veterans, and to assess whether skin disease is associated with disability.
Design: Prospective case comparison study.
Methods: Disabled (n=111) and non-disabled (n=98) Gulf veterans and disabled non-Gulf veterans (n=133) were randomly selected from representative cohorts of those who served in the Gulf conflict 1990-1991, UN Bosnia Peacekeeping Force 1992-1997, or veterans in active service between 1990-91, but not deployed to the Gulf. Disability was defined as reduced physical functioning as measured by the Short Form 36 [score &lt;72.2]. All subjects recruited were examined by a dermatologist, blind to the military and health status of the veteran.
Results: The prevalences of skin disease in disabled Gulf, non-disabled Gulf and disabled non-Gulf veterans were 47.7, 36.7, and 42.8% respectively. Seborrhoeic dermatitis was twice as common as expected in the Gulf veterans (both disabled and non-disabled).
Discussion: Skin disease does not appear to be contributing to ill health in Gulf war veterans, with the exception of an unexplained two-fold increase in seborrhoeic dermatitis.

• A patient with systemic lupus erythematosus had severe hypertension, rapidly worsening renal failure, and multiple successive thrombotic cerebrovascular and retinal lesions develop. In a kidney biopsy specimen luminal thrombi were demonstrated in arteries and arterioles, without vasculitic or inflammatory changes. The patient's plasma was markedly deficient in both prostacyclin stimulating factor (PSF) and vascular plasminogen activator (VPA), and also contained a potent inhibitor of in vitro urokinase-induced fibrinolysis. Treatment with ancrod resulted in striking reversal of the progressive renal damage and clinical recovery from the thrombotic cerebrovascular and retinal lesions. This clinical improvement was associated with improved renal histologic appearance, correction of the PSF and VPA deficiencies, and disappearance of the urokinase inhibitor. Possible mechanisms of action of ancrod are discussed.(Arch Intern Med 1984;144:37-42)

In this paper, we consider the application level performance modeling of parallel machines consisting of a large number of processing elements (PE's) connected in some regular structure such as mesh, tree, hypercube, etc. There are K problem types, each arriving according to a Poisson process, and each of which needs a PE substructure of some given size and topology. Thus several problems can run on the machine simultaneously. It is desired to characterize the performance of such a system under various types of allocation schemes.We show that if the queueing is considered external to our model, it is possible to construct a Markovian model with local balance property. The time for which a substructure is held by a problem could be generally distributed. The model can be solved efficiently using standard techniques; however, because of rather complex structure of the state space, its direct enumeration is difficult to avoid. We also show how the size of the state space can be reduced when the set of allowed substructures is highly regular. We then show how queueing delays can be modeled approximately. Finally, we consider the solution of models involving shared resources such as global memory.

Yellow sol of silver chromate is obtained in gelatin medium when the reactants are either dilute or when the amount of silver nitrate is lesser than the equivalent amounts. In agar agar and aqueous medium, yellow sol is obtained in the presence of sodium citrate. This yellow sol is suddenly converted into a red suspension after a certain period. The time of conversion of yellow sol to red suspension increases as the reactants are diluted or concentration of sodium citrate is increased or when the amount of silver nitrate added is reduced. In presence of sodium citrate and smaller concentrations of AgNO3, a stable yellow sol could be obtained in aqueous medium.

•Presents the thermal model for numerical simulation of potassium carbonate (K2CO3) as a thermochemical energy storage medium.•Presents the performance analysis of honeycomb heat exchanger with potassium carbonate as a thermochemical energy storage medium.•Presents the effects of honeycomb heat exchanger design parameters on thermochemical heat storage bed performance.

•Presents a computational analysis of PCM melting encapsulated in honeycomb cells.•Presents the effects of honeycomb cell size, fin thickness, and inclination angle of the computational domain.•Presents Temperature field, melting front and moving direction of PCM due to convection.•Presents average front surface temperature variation, melt fraction and energy stored with time.

•Presents the thermal model to simulate an adsorption heat storage system for heat and mass transport in the adsorber bed.•Presents the effects of design parameters on adsorber bed performance.•Presents design conditions for energy discharge and peak power for the selected range of parameters.

Relapsing peritonitis was assessed in the continuous ambulatory peritoneal dialysis (CAPD) population of a large, outpatient dialysis facility. Prolonged systemic treatment with antibiotics often fails, resulting in the eventual removal and subsequent reimplantation of the catheter. We have tried a new approach to avoid removal of the peritoneal catheter. Patients were treated by the interruption of CAPD, conversion to hemodialysis or discontinuation of dialysis for a period of 7 to 21 days while continuing systemic antibiotics. Over a period of 76.63 patient years, 69 episodes of bacterial peritonitis occurred (0.9 episodes per patient year). Of these, five episodes could be classified as relapsing peritonitis. Five patients with gram-positive relapsing peritonitis were treated by this regimen; all responded with a cure. Our results suggest that relapsing peritonitis can be eradicated without the removal of the peritoneal catheter.

Zusammenfassung: Zur Bildung von gut definierten Liesegang-Ringen in verschiedenen Gel-Medien ist es wesentlich, die Wirkung des Gel-Mediums auf die Bedingung des unlöslichen Salzes zu untersuchen. Im Fall von Quecksilber werden die gut definierten Ringe in Agar-Agar und Stärkegel entwickelt, wenn das gebildete Sol durch einen der beiden Reaktanten koaguliert werden kann. In Gelatine wird ein sehr stabiles Sol von Quecksilber-Chromat gebildet, welches durch Salzsäure koaguliert wird. Sehr schöne Ringe von Quecksilbersulfat bilden sich in Gelatinegel nur in Anwesenheit von Salzsäure.

Summary In the gelatin medium ‘Revert’ types of rings of mercuric sulphide are obtained. A system containing both ‘Revert’ types of rings and ‘Direct’ types of rings in the same test tube is obtained in the agar agar and starch gels.

Summary The conditions of the formation ofLiesegang rings of copper sulphide in gelatin, agar agar and starch gels are described. ‘Direct’ types of rings are obtained in the gelatin gel whereas ‘Revert’ types of rings are obtained in agar agar and starch gels.

The condition of silver chromate in aqueous, gelatin, agar agar, and starch sols has been studied. It has been found that in the gelatin medium, more of silver chromate is present in ionic state due to the acidity of the medium. The condition of the insoluble substance in agar agar and starch sol is similar to that in the aqueous medium.

Abstract: The effect of the solubility of lead iodide in the formation ofLiesegang rings has been studied. The rings are closely packed as the solubility of lead iodide is decreased. The conditions most suitable for the formation of well definedLiesegang rings of lead iodide in agar agar gel have been found out.

Abstract: The condition of lead chromate in gelatin and agar agar medium has been studied. In presence of agar agar medium the colloid formed is stabilised by lead ions and coagulated by the excess of chromate ions. Lead chromate forms a very stable colloid in the presence of gelatin sol which could not be precipitated by excess of lead ions or chromate ions. Due to the formation of a very stable colloid in gelatin medium, well defined rings of lead chromate are not obtained in gelatin gel.

Zusammenfassung: Während der Bildung vonLiesegang- Ringen von Kupferchromat in Agar-Agar-Gel wurde beobachtet, daß Spiralen, feine und dichte Ringe in Anwesenheit von Licht gebildet werden, während dicke und an Zahl geringere Ringe im Dunkeln erhalten werden. Dieser Unterschied im Verhalten wird der Tatsache zugeschrieben, daß Kupferchromat ein stabileres Sol im Dunkeln im Vergleich zu dem Sol im Hellen bildet.

Zusammenfassung: Das Verhalten von Kupferchromat in verschiedenen lyophilen Solen wurde konduktometrisch untersucht. Es gibt keine Wahrscheinlichkeit dafür, daß sich übersättigte Lösungen dieses Salzes in irgendeinem der lyophilen Sole bilden.

Summary DistinctLiesegang Rings of Copper chromate in gelatin gel are not formed as the salt forms a very stable colloid in this medium. As this sol is coagulated by KH2PO4, well defined rings of Copper chromate in gelatin gel are formed in the presence of this electrolyte.

Abstract: During theLiesegang ring formation of lead chromate in an agar agar gel it was observed that broad bands are formed in the presence of light whereas finer bands are obtained in dark. This difference in behaviour is due to the fact that lead chromate forms a more stable sol in light as compared to that in the dark.

Abstract: DistinctLiesegang rings of lead iodide in gelatin gel are not formed as the salt forms a very stabilised colloid in gelatin medium. The stability of the colloid has been investigated. This sol is precipitated by potassium iodide and barium nitrate. Well definedLiesegang rings of lead iodide are formed in the gelatin gel in the presence of electrolytic barium nitrate.

The effect of the rate of diffusion on the formation ofLiesegang rings of silver chromate in gelatin and agar agar medium has been studied. The rate of diffusion of silver ions in the agar agar gel is much slower than that in gelatin gel during the formation of rings of silver chromate. If the rate of diffusion of silver ions in agar agar gel is increased, even then rings do not form. The only change brought about by the rate of diffusion is for the distance between the successive rings.

The purpose of the 2 studies presented in this article was to determine the clinically appropriate dose of doxercalciferol capsules that is required to maintain similar intact parathyroid hormone control when converting from intravenous (IV) paricalcitol or doxercalciferol.

Background: Gulf war veterans report more symptomatic ill‐health than other military controls, and skin disease is one of the most frequent reasons for military personnel to seek medical care. Aim: To compare the nature and prevalence of skin disease in UK Gulf veterans with non‐Gulf veterans, and to assess whether skin disease is associated with disability. Design: Prospective case comparison study. Methods: Disabled (n=111) and non‐disabled (n=98) Gulf veterans and disabled non‐Gulf veterans (n=133) were randomly selected from representative cohorts of those who served in the Gulf conflict 1990–1991, UN Bosnia Peacekeeping Force 1992–1997, or veterans in active service between 1990–91, but not deployed to the Gulf. Disability was defined as reduced physical functioning as measured by the Short Form 36 [score <72.2]. All subjects recruited were examined by a dermatologist, blind to the military and health status of the veteran. Results: The prevalences of skin disease in disabled Gulf, non‐disabled Gulf and disabled non‐Gulf veterans were 47.7, 36.7, and 42.8% respectively. Seborrhoeic dermatitis was twice as common as expected in the Gulf veterans (both disabled and non‐disabled). Discussion: Skin disease does not appear to be contributing to ill health in Gulf war veterans, with the exception of an unexplained two‐fold increase in seborrhoeic dermatitis.

The effects of a 14-day course of ancrod on fibrinolysis, renal function and structure, and immunologic findings are reported in 37 patients with glomerulonephritis. Patients were divided into two groups. In the first, the level of fibrin degradation products within 48 h was relatively low (<1 mg/ml). In these patients there was a linear relationship between changes in levels of fibrin degradation products and fibrinogen, suggesting that fibrin degradation products derived from ancrod-cleaved-fibrinogen in the circulating pool; in most, level of plasma α2-antiplasmin before treatment was elevated. In the second, the level of fibrin degradation products within 48 h was high (>1 mg/ml). Compared with the change in fibrinogen, a disproportionate increase in levels of fibrin degradation products suggested that a significant amount derived from sources other than plasmin digested ancrod-cleaved-fibrinogen, thus reflecting effective fibrinolysis, perhaps also in tissues; in most, the level of plasma α2-anti-plasmin was normal before treatment. In those with initial high levels of fibrin degradation products, higher levels persisted throughout treatment, changes in other fibrinolysis components were greater, and plasminogen activator inhibitor levels became normal. In patients with initial high but not with initial low response in fibrin degradation products renal function improved within 24 to 48 h and continued to improve thereafter; there was an immediate but temporary increase in proteinuria. Microvascular thrombosis decreased significantly, indicating effective removal of fibrin from glomeruli. The relation of early fibrinolysis to changes in immunologic and histopathologic findings was analyzed in patients with lupus nephritis. With ancrod, there was an increase toward normal of serum C3 and C4, a decrease in serum Igs, gamma globulin and anti-dsDNA antibody and in glomerular C3 and Ig deposits, suggesting that ancrod had favorable effects on immunologic factors. There were no clinical differences in patients with initial high and low responses, but the relationship of microvascular and inflammatory indexes before treatment differed. Initial renal biopsies and those after treatment were carried out on average 28 days apart. Inflammatory and microvascular indexes and glomerular thrombi decreased in patients with initial high levels of fibrin degradation products; fibrosclerosis index and glomerular sclerosis increased in patients with initial low levels of fibrin degradation products. Fibrinolysis expressed as the 48 h (fibridegradation products/fibrinogen) ratio, correlated inversely with change in fibrosclerosis ind and glomerular sclerosis in the whole group, and expecially in those with initial high levels fibrin degradation products. This suggested that ancrod decreased the activity index in both, and prevented further glomerular sclerosis in patients.