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Abstract: A mathematical model based on a generalized Maxwell-Stefan equation has been developed to describe multicomponent ion and water transport inside a cation-exchange membrane. This model has been validated using experimental data and has been used to predict concentration profiles, membrane potential drop, and transport numbers of ions and water for the chlor-alkali process at increased current densities. Several improvements have been made to previously developed Maxwell-Stefan models. In our model, the generalized Maxwell-Stefan equation is written in terms of concentration instead of mole fraction and the fixed group (membrane) concentration is assumed to be constant. We have adapted the Augmented matrix method using the built-in partial differential equation parabolic elliptic (pdepe) solver in Matlab®, and both the concentration and the electrical potential gradients have been solved simultaneously. The boundary conditions are determined with the Donnan equilibrium at the membrane-solution interface. We have also employed semi-empirical correlations to define the Maxwell-Stefan diffusivities inside the membrane. For the bulk diffusivities, we applied the correlations for the concentrated solution instead of the values at infinite dilution. With the diffusivities presented in this work, the model shows a better fit to the experimental data than with previously reported fitted diffusivities. Prediction of the sodium transport number and water transport number is generally good, whereas the deviations with regard to membrane potential might also be related to issues with the experimental data. The model predicts an increase in both sodium and water transport numbers at increased current density operation of chlor-alkali production.Graphical abstract: [ABSTRACT FROM AUTHOR]

The article focuses on the first-line treatment of patients with Idiopathic aplastic anemia (AA). Topics discussed include effectiveness of of antithymocyte globul in the treatment of aplastic anemia and mentions treatment options for AA by allogeneic hematopoietic cell transplantation and immunosuppressive therapy with cyclosporin A.

A brain MRI revealed multiple linear and punctiform T2 hyperintense white matter lesions with subtle enhancement on T1-weighted post-gadolinium MRI (Fig. In Susac's syndrome, brain MRI shows multiple white matter high-intensity lesions on T2-weighted images. According to the proposed criteria for Susac's syndrome, our patient can be classified as probable Susac's syndrome, since no lesions were present in the corpus callosum [[11]]. Our case report shows that Susac's syndrome can occur as a rare neurological irAE and illustrates the difficulties to discern this syndrome from LM. [Extracted from the article]

To assess experiences related to antidepressant use reported to an internet-based medicine reporting system and to compare the nature of the side effects reported by patients with those reported by health care professionals (HCPs). All reports submitted from May 2004 to May 2005 to an internet-based medicine reporting system in The Netherlands related to the use of antidepressants were analysed. Spontaneous reports of adverse drug reactions on antidepressants from HCPs received by The Netherlands Pharmacovigilance Centre Lareb from May 2004 to May 2005 were included for comparison. Of the 2232 individuals who submitted a report to the internet-based medicine reporting system, 258 submitted a report on antidepressants. Of these, 92 individuals (36%) reported on effectiveness, 40 (16%) of whom reported on ineffectiveness, and 217 (84%) submitted a report on side effects, with 202 (78%) reporting a total of 630 side effects that were experienced as negative. Fourteen individuals (5%) reported a practical issue and four (2%) reported a reimbursement issue. Of all 630 side effects reported, 48% resulted in the patient discontinuing the antidepressant therapy; of these 29% did not inform their HCP. Of all the side effects reported, 52% were perceived as “very negative”. In comparison to the side effects reported by HCPs, patients more often reported apathy, excessive sweating, ineffectiveness, somnolence, insomnia, sexual problems and weight increase. Patients report the ineffectiveness and side effects of antidepressant therapy as negative and leading to discontinuation of the therapy. Patients and HCPs differ in the nature of the reported side effects. Patient experiences should be included in the evaluation of antidepressant treatment in clinical practice. [ABSTRACT FROM AUTHOR]

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P Cygni is a prototype for understanding mass loss from massive stars. This textbook star is known first of all because of two great eruptions in the 17th century. In the first half of this century it has given its name to a class of stars which are characterized by spectral lines consisting of nearly undisplaced emissions accompanied by a blue-displaced absorption component. This characteristic P Cygni-type profile betrays the presence of a stellar wind, but P Cygni's wind is quite unlike that of other hot supergiants. P Cygni was the first star that showed the effects of stellar evoluton from a study of its photometric history. It shares some common properties with the so-called Luminous Blue Variables. However, P Cygni is a unique object. This review deals with P Cygni's photometric properties, its circumstellar environment - including infrared and radio observations - and its optical and ultraviolet spectrum. Smaller sections deal with P Cygni's wind structure and evolution. [ABSTRACT FROM AUTHOR]

It is known that a range of firing frequencies can be observed during in vivo muscle activity, yet information is lacking as to how different in vivo-like frequencies may affect force generation of skeletal muscle. This study examined the effects of constant (CSF, constant within one contraction) and decreasing stimulation frequencies (DSF) on mean sarcomere length-force characteristics of rat gastrocnemius medialis fibre bundles. The CSF resulted in an optimal mean sarcomere length ( lSO) of 2.30 (SEM 0.02), 2.46 (SEM 0.03), 2.76 (SEM 0.03) and more than 2.99 (SEM 0.07) μm, for 100, 50, 30 and 15 Hz, respectively. Compared to 100-Hz stimulation, both lSO and the ascending limb of the relationship significantly shifted to higher lengths with lower frequencies. No shift was encountered for the initial part of the descending limb. The DSF reduced the frequency-induced shift to higher mean lengths [ lSO 2.33 (SEM 0.02), 2.52 (SEM 0.08) and more than 2.92 (SEM 0.10) μm, respectively, for 50, 30 and 15 Hz]. No effect of activation time on length-force characteristics was observed. It was concluded from these studies that the frequency and history of stimulation is a major determinant of the length-force characteristics of muscle fibre bundles, and should be taken into account when analysing animal and human locomotion. The previously observed frequency-induced shift in whole muscle length-force relationship resides mainly at the level of fibre bundles. [ABSTRACT FROM AUTHOR]

Abnormalities in coagulation and fibrinolysis are frequently observed in septic shock. The most pronounced clinical manifestation is disseminated intravascular coagulation. Recent studies in human volunteers and animal models have clarified the early dynamics and route of activation of both coagulation and fibrinolytic pathways. In healthy subjects subjected to a low dose of either endotoxin or TNF an imbalance in the procoagulant and the fibrinolytic mechanisms is apparent, resulting in a procoagulant state. Also in patients with septic shock a dynamic process of coagulation and fibrinolysis is ongoing with evidence of impaired fibrinolysis. These abnormalities have prognostic significance; the extent of disturbances of coagulation and fibrinolysis is related to the development of multiple organ failure and death. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the influence of psychiatric symptoms and illness status on the health-related quality of life (HRQOL) of outpatients with Type I and Type II diabetes mellitus. Using a two-stage design, all patients were assessed by two measures of quality of life (Diabetes Quality of Life Measure; Medical Outcome Study Health Survey) and a psychiatric symptoms checklist (SCL-90-R). Patients scoring 63 or greater on the global severity index of the SCL-90-R and 30% below this cutoff were then evaluated using the Structured Clinical Interview for the DSM-III-R (SCID). Quality of life in both Type I and Type II diabetes was influenced by the level of current psychiatric symptoms and presence of co-morbid psychiatric disorder, after controlling for number of diabetic complications (e.g. effect of lifetime psychiatric illness on diabetes-related HRQOL; F=46.8; df=3, 135; p < 0.005). These effects were found consistently across specific domains. Both recent and past psychiatric disorders influenced HRQOL. Separate analyses comparing patients with and without depression showed similar effects. No interaction effects between diabetes type, number of complications, and psychiatric status were found in analyses. Finally, increased severity of psychiatric symptoms was correlated with decreased HRQOL in patients without current, recent, or past psychiatric diagnosis. This study shows the consistent, independent contribution of psychiatric symptoms and illness to the HRQOL of patients with a co-existing medical illness. Thus, psychiatric interventions addressing common conditions, such as depression, could improve the HRQOL of patients without changing medical status. [ABSTRACT FROM AUTHOR]