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During tapping of liquid hot‐metal from the blast‐furnace, the blast‐furnace main trough gets exposed to air and the blast‐furnace‐trough refractory becomes prone to oxidation. In this work, isothermal oxidation kinetics of an Al2O3–SiC–C‐based BFT (Blast‐Furnace‐Trough) refractory castable using a high‐temperature vertical tubular furnace equipped with a microbalance is investigated. Herein, it is observed that up to about 800 °C, carbon only oxidizes, resulting in weight loss in the refractory. Around 900 °C, SiC also starts to oxidize via the passive‐oxidation mechanism, leading to the formation of a mullite phase as a result of the reaction between SiO2 generated via passive oxidation and Al2O3 already present in the refractory. This causes a volume expansion and weight gain, both having a beneficial effect on the refractory performance, which is further validated from apparent porosity measurements. Thus, above 900 °C, simultaneous oxidation of C and passive oxidation of SiC occurs, which eventually stabilizes the weight of the refractory. Around 1100 °C, the oxidation process of the refractory is practically complete, with no further increase in the oxidation rate beyond 1100 °C. The activation energy for the oxidation process is obtained as 37.2 ± 5 kJ mol−1 in the temperature range 600–1150 °C. [ABSTRACT FROM AUTHOR]

The first highly enantioselective oxa-Piancatelli rearrangement has been developed. This process which is catalyzed by a chiral BINOL-derived phosphoric acid rearranges a wide range of furylcarbinols into densely substituted γ-hydroxy cyclopentenones in high yield with excellent diastereo- and enantioselectivities (up to 99 : 1 er). This reaction exhibits a high functional group tolerance and was applied to complex bioactive molecules as well. The products were further manipulated into value-added molecular scaffolds further highlighting their versatility and synthetic utility. [ABSTRACT FROM AUTHOR]

A novel flash ironmaking technology (FIT) that greatly reduces energy consumption and greenhouse gas emissions compared with blast furnace (BF) ironmaking has been developed at the University of Utah. In this technology, a falling stream of iron ore concentrate is directly converted to metallic iron by reducing gases such as hydrogen, natural gas or coal gas in a flash furnace. In this work, the interaction of magnesia-carbon (MgO–C) refractory with ferrous oxide (FeO) under the conditions of the novel FIT has been investigated. Oxidation of carbon from the MgO–C refractory occurred and magnesiowustite (Mg x Fe 1-x O) solid solution was formed as a result of the interaction between magnesia (MgO) in the refractory and ferrous oxide (FeO). A solid-state diffusion based kinetics model was developed to describe the growth of the magnesiowustite (Mg x Fe 1-x O) formed. Experiments were carried out with ferrous oxide (FeO) and MgO–C refractory in the temperature range 1200–1400 °C under flash ironmaking atmospheres. Reacted samples from FeO–MgO–C experiments were analyzed using Scanning Electron Microscopy-Energy Dispersive X-Ray spectroscopy (SEM-EDX) and Electron Probe Micro-Analyzer (EPMA) and the formation of the magnesiowustite solid solution under flash ironmaking conditions was confirmed. Using the kinetics model and the composition profiles determined with EPMA, the values of interdiffusion coefficient ( D F e − M g ) were determined as a function of the magnesiowustite composition. Also, an average value of the interdiffusion coefficient ( D ‾ F e − M g ) was calculated such that it reasonably reproduced the concentration profile of the cations over the entire composition range. The values of D ‾ F e − M g calculated in this work agreed closely with those obtained independently from experiments on the interaction between MgO–C and metallic Fe, thereby validating the interaction mechanism and the proposed kinetics model. The solid-state diffusion was a thermally activated process and the activation energy ( E a ) for D ‾ F e − M g was calculated as 398 kJ/mol. [ABSTRACT FROM AUTHOR]

The interaction of a magnesia-carbon refractory with iron under flash ironmaking conditions has been investigated in this work. Oxidation of carbon from the magnesia-carbon refractory took place and the formation of magnesiowustite (Mg x Fe 1-x O) solid solution occurred as a result of the interaction between magnesia (MgO) in the refractory with iron (Fe). A kinetics model for the growth of magnesiowustite (Mg x Fe 1-x O) was developed based on the counterdiffusion of Fe2+ and Mg2+ cations through it. Experiments were conducted with iron powder and magnesia-carbon refractory in the temperature range 1200–1400 °C under gas atmospheres relevant to flash ironmaking and analyses of reacted samples using SEM-EDX and EPMA techniques confirmed the formation of magnesiowustite (Mg x Fe 1-x O). Using the kinetics model and the composition profiles determined with EPMA, the values of interdiffusion coefficient ( D ¯ F e - M g), averaged over the composition range, were calculated. The activation energy (E a) for the solid-state diffusion process was determined to be 377 kJ/mol. [ABSTRACT FROM AUTHOR]

Melanoma is one of the four major types of skin cancers caused by malignant growth in the melanocyte cells. It is the rarest one, accounting to only 1% of all skin cancer cases. However, it is the deadliest among all the skin cancer types. Owing to its rarity, efficient diagnosis of the disease becomes rather difficult. Here, a deep depthwise separable residual convolutional algorithm is introduced to perform binary melanoma classification on a dermoscopic skin lesion image dataset. Prior to training the model with the dataset noise removal from the images using non‐local means filter is performed followed by enhancement using contrast‐limited adaptive histogram equilisation over discrete wavelet transform algorithm. Images are fed to the model as multi‐channel image matrices with channels chosen across multiple color spaces based on their ability to optimize the performance of the model. Proper lesion detection and classification ability of the model are tested by monitoring the gradient weighted class activation maps and saliency maps, respectively. Dynamic effectiveness of the model is shown through its performance in multiple skin lesion image datasets. The proposed model achieved an ACC of 99.50% on international skin imaging collaboration (ISIC), 96.77% on PH2, 94.44% on DermIS and 95.23% on MED‐NODE datasets. [ABSTRACT FROM AUTHOR]

A novel flash ironmaking technology (FIT) has been developed at the University of Utah based on the direct reduction of iron ore concentrate by a reducing gas such as hydrogen, natural gas, coal gas or a mixture thereof. In this work, the interaction of ferrous oxide (FeO) with alumina (Al 2 O 3) refractory under flash ironmaking conditions has been studied. A thermodynamic basis for the interaction process has been developed by considering the Fe–Al–O system and a kinetic model based on solid-state diffusion is formulated to describe the growth of the hercynite (FeAl 2 O 4) spinel formed as a result of the interaction between FeO and Al 2 O 3. Experiments were conducted with FeO powders and pure Al 2 O 3 refractory in the temperature range 1200–1400 °C under gas atmospheres relevant to FIT. The analyses of reacted samples using XRD, SEM-EDX and EPMA techniques confirmed the formation of the hercynite (FeAl 2 O 4) spinel under FIT conditions and results showed that the proposed kinetic model appropriately describes the growth of the hercynite spinel layer, which obeyed the parabolic rate law at all the three temperatures. Furthermore, using the kinetic model, expressions for the parabolic rate-constants ( k 1 ) and the effective diffusivity ( D e f f ¯) were obtained and their respective values at the experimental temperatures were determined. The values of D e f f ¯ calculated in this study agreed closely with those obtained independently by the authors from experiments on Fe–Al 2 O 3 interaction thereby corroborating the interaction mechanism and the associated reaction scheme. The solid-state diffusion was temperature-dependent, with an activation energy value of 268 kJ/mol. [ABSTRACT FROM AUTHOR]

We study the approximation capabilities of two families of univariate polynomials that arise in applications of quantum signal processing. Although approximation only in the domain [ 0 , 1 ] is physically desired, these polynomial families are defined by bound constraints not just in [ 0 , 1 ] , but also with additional bound constraints outside [ 0 , 1 ]. One might wonder then if these additional constraints inhibit their approximation properties within [ 0 , 1 ]. The main result of this paper is that this is not the case — the additional constraints do not hinder the ability of these polynomial families to approximate arbitrarily well any continuous function f : [ 0 , 1 ] → [ 0 , 1 ] in the supremum norm, provided f also matches any polynomial in the family at 0 and 1. We additionally study the specific problem of approximating the step function on [ 0 , 1 ] (with the step from 0 to 1 occurring at x = 1 2 ) using one of these families, and propose two subfamilies of monotone and non-monotone approximations. For the non-monotone case, under some additional assumptions, we provide an iterative heuristic algorithm that finds the optimal polynomial approximation. [ABSTRACT FROM AUTHOR]

An enantioselective formal C(sp2)−H vinylation of prochiral 2,2-disubstituted cyclopentene-1,3-dione is presented. This vinylative desymmetrization is realized by using a two-step procedure that consists of a catalytic enantioselective vinylogous Michael addition of deconjugated butenolides to cyclopentene-1,3-dione and a base-mediated decarboxylation. The overall process utilizes deconjugated butenolides as the source of the highly substituted vinyl unit. Five-membered carbocycles containing a remote all-carbon quaternary stereogenic center are obtained in good yields and with good to high enantioselectivities. [ABSTRACT FROM AUTHOR]

Background: Depression is a major complication during treatment of chronic hepatitis C virus (HCV) infection with interferon- (IFN- ). It is unclear whether antidepressants can prevent IFN-induced depression in patients without psychiatric risk factors. Objective: To examine whether preemptive antidepressant treatment with escitalopram can decrease the incidence or severity of depression associated with pegylated IFN- in HCV-infected patients without a history of psychiatric disorders Design: Randomized, multicenter, double-blind, prospective, placebocontrolled, parallel-group trial. Setting: 10 university and 11 academic hospitals in Germany. Patients: 181 HCV-infected patients with no history of psychiatric disorders enrolled between August 2004 and December 2008. Intervention: Escitalopram, 10 mg/d (n 90), or placebo (n 91) administered 2 weeks before and for 24 to 48 weeks during antiviral therapy. Intervention: Escitalopram, 10 mg/d (n 90), or placebo (n 91) administered 2 weeks before and for 24 to 48 weeks during antiviral therapy. Measurements: The primary end point was the incidence of depression, defined as a Montgomery-Asberg Depression Rating Scale (MADRS) score of 13 or higher. Secondary end points were time to depression, incidence of major depression according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, quality of life, sustained virologic response, tolerability, and safety. Results: 32% (95% CI, 21% to 43%) of the patients in the escitalopram group developed a MADRS score of 13 or higher compared with 59% (CI, 48% to 69%) in the placebo group (absolute difference, 27 percentage points [CI, 12 to 42 percentage points]; P 0.001). Major depression was diagnosed in 8% of the patients in the escitalopram group and 19% in the placebo group (absolute risk difference, 11 percentage points [CI, 5 to 15 percentage points]; P 0.031). Tolerability and safety parameters did not differ between the groups. In the escitalopram group, 56% (CI, 46% to 66%) of patients achieved a sustained virologic response compared with 46% (CI, 37% to 57%) in the placebo group (P 0.21). Limitations: Results might not be generalizable to patients with previous psychiatric disease. Some patients withdrew or developed temporary elevated MADRS scores after randomization but before the study medication was started. Conclusion: Prophylactic antidepressant treatment with escitalopram was effective in reducing the incidence and severity of IFNassociated depression in HCV-infected patients without previous psychiatric disease. Primary Funding Source: Roche Pharma and Lundbeck. [ABSTRACT FROM AUTHOR]

A letter to the editor about the use of levetiracetam as monotherapy or add-on to valproate in the treatment of acute mania is presented.

Background: Cytokine treatment with Interferon-alpha (IFN-α) represents a clinical model of immune associated depression, but it remains unclear if it is of the same entity as major depressive disorder (MDD). The study focuses on possible gender differences in IFN-α induced depression and effects of a pre-emptive antidepressant treatment.Methods: Data from 181 patients with chronic hepatitis C infection (cHC) without history of mental illnesses undergoing treatment with IFN-α 2a and ribavirin were re-analyzed for gender effects. Patients with a pre-emptive antidepressant therapy with Escitalopram (n = 90, verum group) to prevent IFN-induced depression were compared to patients who received placebo (n = 91). Depressive symptoms before and during HCV-treatment were assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), Beck's Depression Inventory (BDI) and the Hamilton Anxiety Rating Scale.Results: We found significant differences regarding the incidence and severity of depressive symptoms between men and women for patients without antidepressant pre-treatment (placebo group). Significantly more women without pre-emptive antidepressant therapy suffered from clinically relevant depression (MADRS values ≥ 13, p = 0.041) and self-rated depressive symptoms (BDI ≥ 17, p = 0.024). Antidepressant pre-treatment showed comparable effects regarding the reduction of incidence and severity of depression in both women and men.Conclusions: Compared to MDD, IFN-alpha-induced depression in patients with cHC is also characterized by gender differences with an increased risk for women but no gender difference regarding the effects of an antidepressant pre-treatment is found. Our data strengthens the hypothesis that Interferon-induced depression serves as a clinical model for immune related depressive disorders. [ABSTRACT FROM AUTHOR]

Interaction of alumina (Al2O3) refractory with FeO–SiO2 and FeO–SiO2–CaO slags relevant to the flash ironmaking technology (FIT) is investigated in this work. It is shown that for slags relevant to FIT, the interaction process can be described by a kinetic model based on counter diffusion of only Fe2+ and Al3+ cations through hercynite (FeAl2O4) formed as a result of the interaction. The diffusion of Si4+ and Ca2+ ions through FeAl2O4 can be neglected, and the only effect these cations have is that they affect the activity of iron oxide (FeO) at the slag–FeAl2O4 boundary. Analyses of reacted samples using X‐ray diffraction (XRD), scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM–EDX), and electron probe microanalyzer (EPMA) show that the proposed model appropriately describes the growth of FeAl2O4 with the parabolic rate law being obeyed for both FeO–SiO2 and FeO–SiO2–CaO slags in the temperature range of 1200–1400 °C. The values of effective diffusivity (Deff¯) are calculated independently from experiments with FeO–SiO2 and FeO–SiO2–CaO slags agreed with each other, with the activation energy values in the two cases being 246 and 253 kJ mol−1, respectively. These values of Deff¯ and activation energy are in good agreement with the corresponding values obtained previously from Fe–Al2O3 and FeO–Al2O3 systems. [ABSTRACT FROM AUTHOR]

The article examines the use of bupropion as an effective and safe treatment alternative for patients with adjustment disorders, which are states of subjective distress and emotional disturbance, usually interfering with social functioning and performance. Adjustment disorders arise in the period of adaptation to a significant life change or a stressful life event, and manifest as depressed mood, anxiety or worry. A case report of a male patient with adjustment disorders is presented.

This article presents a case study involving an obsessive-compulsive disorder (OCD) patient in whom a treatment regimen with escitalopram was successfully augmented with aripiprazole. Background information on OCD and cognitive behavioural therapy is provided, as well as a discussion on the clinical history of the patient and details on the management of the disease.

In recent years, there has been growing interest in the use of carbon fibers for a wide variety of applications, including automotive, aerospace, wind turbine, sporting goods, energy storage, civil engineering, and grid applications, etc. This momentum is primarily driven by the excellent mechanical, electrical, and thermal properties of carbon fibers. Asphaltenes (i.e., the heavy fraction of bitumen) have recently been identified as promising low-cost precursors for developing low-cost carbon fibers that could accelerate the widespread adoption of carbon fibers in existing and new industries. Here we report on the techno-economic and life cycle assessment of asphaltene-derived carbon fiber (A-CF) production to assess its economic and climate benefits. Our techno-economic analysis indicates that the production cost can be kept below USD 9 per kg of A-CF, which is primarily due to the use of the inexpensive asphaltene precursor. Further cost reduction can be achieved by reducing the energy use of the high-temperature carbonization step, which takes up nearly 25% of the production cost. Furthermore, cradle-to-gate life cycle analysis (LCA) reveals that A-CF can offer potential climate benefits as compared to the incumbent precursors (PAN, pitch, and lignin-based CF), with the lowest global warming potential (GWP) of ∼7.46 kg CO2-eq per kg of A-CF. Our analysis indicates that precursor (asphaltene) extraction during bitumen partial upgrading stands out as the most energy-intensive phase (32% of total A-CF production energy) and in turn dictates the net environmental impacts. Finally, a commercial scale analysis depicts that our A-CF route can reduce greenhouse gas (GHG) emissions by 48% compared to the combustible use of asphaltene. Moreover, the A-CF route can also displace energy-intensive PAN-based CF (P-CF) with an annual GHG reduction potential of 2081 kilo tonne CO2-eq and 4162 kilo tonne CO2-eq compared to P-CF if A-CF penetrates 20% and 40%, respectively of the projected global CF market in 2032. [ABSTRACT FROM AUTHOR]

Psychiatric comorbidity is a common problem in patients with substance use disorders. Patients with psychiatric diseases and/or substance abuse have an increased risk for hepatitis C virus (HCV) infection. Furthermore, psychiatric problems occur frequently during antiviral treatment and may be associated with the use of interferon alpha (IFN-α) but also with the primary psychiatric condition. As a consequence, substance abuse and/or acute psychiatric problems are still important reasons for nontreatment of chronic HCV infection. However, prospective and controlled data from recent years showed that if an interdisciplinary treatment is provided, patients with substance use disorders and/or psychiatric diseases do not differ regarding sustained virologic response or IFN-α–associated complications such as depression when compared with controls. Moreover, depression as the most important acute IFN-α–associated psychiatric adverse event can be acutely treated or even prevented by antidepressant pretreatment. Other, more rare but severe complications such as mania, psychotic symptoms, or delirium need individual psychiatric interventions. [ABSTRACT FROM AUTHOR]

Background: This paper describes a model for estimating COVID-19 related excess deaths that are a direct consequence of insufficient hospital ward bed and intensive care unit (ICU) capacity.Methods: Compartmental models were used to estimate deaths under different combinations of ICU and ward care required and received in England up to late April 2021. Model parameters were sourced from publicly available government information and organisations collating COVID-19 data. A sub-model was used to estimate the mortality scalars that represent increased mortality due to insufficient ICU or general ward bed capacity. Three illustrative scenarios for admissions numbers, 'Optimistic', 'Middling' and 'Pessimistic', were modelled and compared with the subsequent observations to the 3rd February.Results: The key output was the demand and capacity model described. There were no excess deaths from a lack of capacity in the 'Optimistic' scenario. Several of the 'Middling' scenario applications resulted in excess deaths-up to 597 deaths (0.6% increase) with a 20% reduction compared to best estimate ICU capacity. All the 'Pessimistic' scenario applications resulted in excess deaths, ranging from 49,178 (17.0% increase) for a 20% increase in ward bed availability, to 103,735 (35.8% increase) for a 20% shortfall in ward bed availability. These scenarios took no account of the emergence of the new, more transmissible, variant of concern (b.1.1.7).Conclusions: Mortality is increased when hospital demand exceeds available capacity. No excess deaths from breaching capacity would be expected under the 'Optimistic' scenario. The 'Middling' scenario could result in some excess deaths-up to a 0.7% increase relative to the total number of deaths. The 'Pessimistic' scenario would have resulted in significant excess deaths. Our sensitivity analysis indicated a range between 49,178 (17% increase) and 103,735 (35.8% increase). Given the new variant, the pessimistic scenario appeared increasingly likely and could have resulted in a substantial increase in the number of COVID-19 deaths. In the event, it would appear that capacity was not breached at any stage at a national level with no excess deaths. it will remain unclear if minor local capacity breaches resulted in any small number of excess deaths. [ABSTRACT FROM AUTHOR]

The article presents a case study of an eight-year-old girl who was presented with complaints of intermittent discharge from a pit in the medial surface of right pinna since early childhood. Examination found an opening above the lobule leading to a swelling that reached the post-auricular sulcus. The study demonstrates that identical cysts, sinuses or tracts are derived from malformations of the first branchial sinus which contributes to the development of the external auditory canal (EAC).

Abstract: Background: Deficits in working memory (WM) are a core symptom of schizophrenia patients and have been linked to dysfunctional prefrontal activation, which might be caused by a mesocortical hypodopaminergic state. Aripiprazole – a partial dopamine antagonist – is a novel antipsychotic, which increases frontal dopamine concentrations in preclinical studies. However, little is known about specific medication effects on the modulation of frontal activation during WM performance. Methods: We measured BOLD-response during a WM task in a longitudinal fMRI-study in eleven schizophrenia patients first when they received conventional antipsychotics (T1) and a second time after they had been switched to aripiprazole (T2). A healthy control group matched for age, handedness and gender was investigated at two corresponding time points. Data was analyzed with SPM5 in a 2×2×2 design (group×session×task). Results: Schizophrenia patients showed fewer correct responses compared to healthy controls at T1 and a trend-wise normalization at T2. The task activated the fronto-parietal network during the contrast 2-back>0-back in all participants. At T1 patients revealed a hypoactivation in the dorsal anterior cingulate cortex (ACC), which normalized after switch to aripiprazole and correlated with improved task performance. This was due to a significant increase in the patients group while the control group did not change, as corroborated by a significant group×time interaction in this region. Conclusions: This study showed for the first time that the partial dopamine antagonist aripiprazole increases BOLD-signal during a WM task in the cognitive part of the ACC in schizophrenia patients, which may reflect its beneficial effect on cognitive deficits. [Copyright &y& Elsevier]

Scheuch K, Bräunig P, Gauggel S, Kliesow K, Sarkar R, Krüger S. Emotional vulnerability and cognitive control in patients with bipolar disorder and their healthy siblings: a pilot study. Objective: There is evidence that, even in remission, patients with bipolar disorder (BD) have deficits in cognitive function and emotional regulation. Siblings of patients with BD are also reported to exhibit minor dysfunction in neuropsychological domains. In this study, we examined the interference of acute mood state with reaction time (RT) and response inhibition in euthymic patients with BD, in their healthy siblings and in healthy controls. Methods: A total of 34 patients with bipolar I disorder, 22 healthy siblings and 33 healthy controls performed a stop-signal paradigm after induction of a transient intense sadness and a relaxed mood state. The differences in RT and the response inhibition were compared between the groups. Results: Euthymic patients with BD displayed a higher emotional reactivity compared with their siblings and with controls. Compared with controls, patients with BD showed longer RTs in a relaxed mood state and a delay in response inhibition during emotional activation. Conclusions: The present study provides evidence for the clinical observation that patients with BD have shorter RTs when in a state of emotional arousal rather than in a relaxed state. Inhibitory deficits in these patients may be because of a too strong emotional arousal. The results show that in patients with BD, relaxation and emotional arousal are inversely associated with performance in a neuropsychological task. This is in contrast to findings in healthy individuals suggesting a dysbalance in emotional regulation in these patients. [ABSTRACT FROM AUTHOR]