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Visible light active, highly stable, nontoxic, and efficient photocatalysts based on 1 %, 3 %, and 5 % Mn@Co3O4 were synthesized and functionalized with reduced graphene oxide. The X-rays diffraction (XRD) spectroscopy and FT-IR spectroscopy were employed for structural and functional group studies. Under visible light irradiation, photocatalytic activities of 1 %, 3 %, and 5 % Mn@Co3O4/rGO nanocomposites were studied for the degradation of organic pollutant methylene blue. Almost 85.4 %, 90.2 %, and 93.4 % degradation of methylene blue were observed after 80 min with 1 % Mn@Co3O4/rGO, 3 % Mn@Co3O4/rGO, and 5 % Mn@Co3O4/rGO respectively. The prepared nanocomposites followed pseudo-first-order kinetic studies. Among all samples, the 5 % Mn@Co3O4/rGO showed maximum degradation of 93.4 % in 80 min. Moreover, 5 % Mn@Co3O4/rGO nanocomposite maintained its excellent dye degradation ability even after three cycles. [ABSTRACT FROM AUTHOR]

Industrialization and urbanization have now become major factors in damaging different segments of the environment. Synthesis of novel nanomaterials for the removal of dyes and free radicals from aqueous medium has become a challenge for the researchers. The present work describes formation of novel-franklinite (ZnFe2O4) nanoparticles (FNPs) which have been synthesized adopting economical route of green method using extracts of fresh and dried leaves of Coriandrum sativum. The fabricated NPs were characterized employing state of the art analytical techniques including UV-visible, FTIR, SEM and XRD. The nanocatalyst exhibited excellent catalytic properties for the degradation of eosin yellow up to 86 % in 22 min and 90 % in 16 min using zinc-ferrite NPs synthesized using dried and fresh leaves respectively. Antioxidant activity of ZnFe2O4 in terms of DPPH and ABTS free radicals scavenging was also determined. Nanoparticles synthesized using fresh leaves exhibited better antiradical potential in comparison to NPs synthesized dried leaves. Therefore, synthesis of FNPs with active features can be achieved using extract of fresh plant. Franklinite NPs can be used as promising photocatalyst for the degradation of organic pollutants and scavenging of free radicals. [ABSTRACT FROM AUTHOR]

Silica-rich dealuminated kaolin (SRDK), produced as a by-product in alum industry, is still considered as waste materials in Egypt. Expansion of aquaculture along the banks of Nile River and its canals negatively affects water quality due to formation of ammonia. The current investigation aims to eradicate ammonia from aquaculture systems via an integrated approach of converting SRDK to pure zeolite Y in two-step process. The main constituent of SRDK is amorphous silica with a small amount of unreacted metakaolin and crystalline silica. XRD and FTIR proved that zeolitization started by mechanochemical activation at room temperature. However, hydrothermal treatment at 105 °C and 125 °C produces zeolite Y with different Si/Al ratios and microcrystalline quartz is completely reacted at 125 °C. The adsorption isotherm data of ammonia was best fitted by Freundlich model. Zeolite Y produced from 80% SRDK and 20% metakaolin at 125 °C has a high efficiency to remove ammonia from aquaculture. Highlights: Silica-rich dealuminated kaolin (SRDK) was converted to pure zeolite Y in two-step process. Zeolite formation stated by Mechanochemical activation at room temperature. Hydrothermal treatment at 105 °C and 125 °C produces zeolite Y with different Si/Al ratios. The ammonia adsorption isotherm was best fitted by Freundlich model. Zeolite Y produced from SRDK and 20% metakaolin has a high efficiency to remove ammonia from aquaculture. [ABSTRACT FROM AUTHOR]

Due to increasingly stringent environmental regulations imposed by governments throughout the world, the manufacture of low-sulfur fuels has received considerable assiduity in the petroleum industry. In this investigation, mesoporous V2O5-decorated two-dimensional ZnO nanocrystals were manufactured using a simple surfactant-assisted sol–gel method for thiophene photocatalytic oxidative desulfurization (TPOD) at ambient temperature applying visible illumination. When correlated to pure ZnO NCs, V2O5-added ZnO nanocomposites dramatically improved the photocatalytic desulfurization of thiophene, and the reaction was shown to follow the pseudo-first-order model. The photocatalytic effectiveness of the 3.0 wt.% V2O5-ZnO photocatalyst was the greatest among all the other samples, with a rate constant of 0.0166 min−1, which was 30.7 significantly greater than that of pure ZnO NCs (0.00054 min−1). Compared with ZnO NCs, and owing to their synergetic effects, substantial creation of hydroxyl radical levels, lesser light scattering action, quick transport of thiophene species to the active recenters, and efficient visible-light gathering, V2O5-ZnO nanocomposites were found to have enhanced photocatalytic efficiency. V2O5-ZnO nanocomposites demonstrated outstanding stability during TPOD. Using mesoporous V2O5-ZnO nanocomposites, the mechanism of the charge separation process was postulated. [ABSTRACT FROM AUTHOR]

Composites of NbC/ZrO2 reinforced with different weight ratios of Cr metal were prepared by dynamic compaction combustion from a blend of Nb2O5–Zr–Cr powders. Factors controlling the synthesis process, the microstructure, and the mechanical properties of the samples, such as Cr wt% and the compression loads were studied. The samples were characterized by XRD, SEM, porosity, and hardness measurements. The porosity value of the sample with no additives was high and reached 31.6 vol%. A sudden decrease in the sample porosity to 2.4 vol % was noticed for the sample containing 3.0 wt% of Cr. A high‐density sample with less than 2.0 vol % porosity and maximum hardness of 1038 HV was produced using 5.0 wt% Cr under 300 MPa compression load. Detailed thermodynamic calculations for the effect of Cr additives on the physicochemical properties of the system were introduced. [ABSTRACT FROM AUTHOR]

Summary: The high electrochemical stability of Zirconia (ZrO2) at high potentials strongly suggested it as an alternative to carbon supports, which experience reduced efficiency due to some corrosion problems particularly during prolonged electrocatalysis activity. However, the use of ZrO2 was limited by its low electrical conductivity and surface area. In this work, we developed a methodology for synthesizing monoclinic ZrO2 NPs with increased surface area and improved electrical/electrocatalytic characteristics without using any carbon‐based co‐support material or any metallic nanoparticles. In this context, for the first time, highly defective hydroxyl‐functionalized ZrO2 NPs (designated here as ZT NPs) were prepared by a hydrothermal route in the presence of sodium tartrate as a mineralizer. XRD analysis demonstrated that the produced zirconia was semicrystalline microspheres, consisting of monoclinic ZrO2 NPs with high lattice defects. The addition of tartrate ions decreased the crystallite size and increased the defects and microstrain. At the same time, the alkaline hydrogen evolution reaction (HER) catalytic activity of ZrO2 NPs was significantly increased when using sodium tartrate as mineralizer; the overpotential required to obtain 10 mA cm−2 (η10) dropped down from 490 to merely 235 mV, while an exchange current density (jo) increased 12 times to 0.22 mA cm−2. The presence of structural defects (revealed by XRD) and the increased number of active surface sites contending O‐H groups (evidenced from ATR‐FTIR and XPS) as well as the enhanced electrochemical active surface area (confirmed from double‐layer capacitance measurements) were the main reasons behind the high catalytic performance. The ZrO2 NPs catalytic activity increased even further during the long‐term stability tests under severe cathodic conditions (ZT*, ZrO2 NPs obtained after the long‐term stability, has jo = 0.47 mA cm−2 and η10 = 140 mV), approaching the activity of Pt/C catalyst. This process was assisted by mineralizer removal from the catalyst (testified by XPS). Our studies revealed that ZT* are characterized by larger electroactive surface area and more structure defects compared to ZT, where surface area and microstrains resulting from surface hydroxylation open cavities in zirconia structure. [ABSTRACT FROM AUTHOR]

Half Metallic Ferromagnetism and Transport Properties of Zinc Chalcogenides ZnX 2 Se 4 (X = Ti, V, Cr) for Spintronic Applications. In the original publication [[1]], Affiliation 10 is not the author's address in the preparation stage of this article, so it needs to be deleted and listed in the front note: current address. Only the affiliation number has changed: Nasser Y. Mostafa SP 1,10 sp changed to Nasser Y. Mostafa SP 1 sp . [Extracted from the article]

Existing concrete structures may require strengthening or stiffening in order to increase their structural performance. This paper presents the results of an experimental investigation for enhancing the shear capacity of reinforced concrete beams using two different techniques, external pre-tensioned stirrups and internal bonded vertical steel bars. A total of seven beams were tested in this program. All beams were designed to fail in shear mode; to assess the actual increase in shear strength by devised strengthening techniques. One of the beams was tested as control beam; whereas other beams were strengthened as the following. Two beams were strengthened with vertical internal epoxy bonded bars, two beams were strengthened with vertical internal epoxy bonded with end anchored bars, and two beams were strengthened with vertical externally anchored stirrups. All techniques were found to be effective in enhancing the shear strength of beams. However, the internal epoxy bonded and end anchored bars were found to be more effective than non anchored bars. Beams strengthened using this technique failed at a load almost 110 % higher than the control beam. The externally anchored steel stirrups provided an average of 100 % increase in shear capacity as compared to the control beam, while the internal epoxy bonded bars without mechanical anchors failed at a load 60% higher than the control beam. [ABSTRACT FROM AUTHOR]

In this study, a high-density ZrN/ZrSi2 composite reinforced with ZrO2 as an inert phase was synthesized under vacuum starting with a Zr-Si4N3-ZrO2 blend using combustion-synthesis methodology accompanied by compaction. The effects of ZrO2 additions (10–30 wt%) and compression loads (117–327 MPa) on the microstructure, porosity and hardness of the samples were studied. The process was monitored using XRD, SEM, EDS, porosity, density and hardness measurements. Thermodynamic calculations of the effect of ZrO2 addition on the combustion reaction were performed including the calculation of the adiabatic temperatures and the estimation of the fractions of the liquid phase. The addition of up to 20 wt% ZrO2 improved the hardness and reduced the porosity of the samples. Using 20 wt% ZrO2, the sample porosity was reduced to 1.66 vol%, and the sample hardness was improved to 1165 ± 40.5 HV at 234 MPa. [ABSTRACT FROM AUTHOR]

In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (Tc), spin polarization, half magnetic ferromagnetism and transport properties of ZnX2Se4 (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of Tc is perceived for ZnCr2Se4. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μB of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy Δ E crystal, exchange energies Δ x(d), Δ x (pd) and exchange constants (No α and No β). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0–400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 1011 W/mK2) among studied compounds. [ABSTRACT FROM AUTHOR]

Background Actinic keratosis (AK), the most common premalignant skin condition, can represent a management challenge. Treatment should not only be effective, but also well tolerated and allow for good cosmesis on typical sun-exposed highly visible body sites. Objectives The primary objective was to compare the lesion response and subject preference for topical methyl aminolaevulinate (MAL)-photodynamic therapy (PDT) vs. cryotherapy for the treatment of AK. Methods In this 24-week, multicentre, randomized, intraindividual (right–left) study, subjects received both one treatment session of MAL-PDT and a double freeze–thaw cryotherapy; the treatments were randomly allocated to either side of the face/scalp. Lesions with a noncomplete response were retreated after 12 weeks. The primary assessments were the subject's overall preference and lesion response at week 24. Secondary assessments included lesion response at week 12, cosmetic outcome, subject and investigator cosmetic outcome preference at week 24, and investigator overall preference at week 24. Skin discomfort and adverse events were also evaluated. Results In total, 119 subjects with 1501 lesions were included in the study. At week 12, treatment with MAL-PDT resulted in a significantly larger rate of cured lesions relative to cryotherapy (percentage lesion reduction from baseline: 86·9% vs. 76·2%; P < 0·001). At week 24, both treatment groups showed a high rate of cured lesions (89·1% for MAL-PDT vs. 86·1% for cryotherapy; P = 0·20; 95% confidence interval: −1·62 to 7·67). Results for subject and investigator preferences as well as cosmetic outcome favoured MAL-PDT. Both treatment regimens were safe and well tolerated. Conclusions The present study shows that, when treated with both MAL-PDT and cryotherapy, subjects significantly prefer MAL-PDT treatment for AK. MAL-PDT is an attractive treatment option for AK, with comparable efficacy and superior cosmetic outcomes compared with double freeze–thaw cryotherapy. [ABSTRACT FROM AUTHOR]

This prospective controlled study aimed to evaluate the effectiveness and acceptability of a computer program (CAL) designed to educate patients about skin protection including signs of melanoma. Two hundred and twenty-seven patients were recruited either from the Pigmented Lesion Clinic (PLC) or the Orthopaedic Fracture Clinic (OFC). A baseline measure of anxiety was obtained and subjects were allocated to either non-interactive, interactive or control conditions. Measures of anxiety and knowledge about malignant melanoma and skin protection were obtained prior to discharge from the clinic and knowledge was assessed again at 1-week follow-up. Results indicate that, although anxiety in the PLC subjects decreased significantly more than in the OFC patients, there was no significant effect of intervention. There was a significant effect of intervention on knowledge (F = 81·06, d.f. 2,218, P < 0·0001) with participants having better knowledge on leaving the clinic in the interactive CAL condition than in both the Non-interactive condition and control. Non-interactive CAL was associated with higher knowledge than control. Knowledge gains were maintained at 1-week follow-up. [ABSTRACT FROM AUTHOR]

Histology sections from 61 cases of squamous cell carcinoma (SCC) of the vulva presenting after 1988 were reviewed for evidence of associated epithelial abnormality. Of the 50 patients with epithelium adjacent to the tumour, 24 had histological evidence of lichen sclerosus (LS), 20 of severe vulvar intraepithelial neoplasia (VIN 3), 22 of human papilloma virus (HPV) infection and three of lichen planus (LP). The clinical records and the original histology report were also subsequently reviewed and with the exception of VIN 3, these disorders were poorly reported by both clinicians and pathologists. Lichen sclerosus was diagnosed clinically in only two of the 36 hospital records available for inspection. Old terminology was used to describe some patients with epithelial disease (erythroleucoplakia in one patient with LS, leucoplakia in two patients with LS and one with LP). This study demonstrates the need to adopt standard nomenclature and increase the awareness of epithelial disease associated with SCC of the vulva among clinicians and pathologists. [ABSTRACT FROM AUTHOR]

Acute febrile neutrophilic dermatosis (Sweet's syndrome) is reported to be a marker for underlying malignancy. Much of the evidence for this is based on case reports, small series of cases and reviews of the literature. In order to clarify the association with malignancy and determine the common clinical features of Sweet's syndrome, we reviewed the case notes of patients presenting to six dermatology units in the U.K. Eighty-seven cases of histologically proven Sweet's syndrome were reviewed. Fourteen patients {16%} developed associated malignancy, predominantly haematological, two patients (2%) had a history of previous malignancy and four patients (5%) had premalignant conditions (monoclonal gammopathy, two: myelodysplasia, two). Malignancy developed up to a year after presentation with Sweet's syndrome. Patients with associated malignancy were more likely to be anaemic (P<0.01) at presentation, had a lower mean platelet count (207 × 109/L vs. 332×109/L: P<0.003) and were, on average, older 59 years vs. 49 years: P = 0.002). Contrary to previous reports, a greater percentage of females developed malignancy than males. [ABSTRACT FROM AUTHOR]

Cyclosporin has been shown to be effective in the treatment of adult atopic dermatitis, but there are no clinical trials evaluating its use in childhood. Atopic dermatitis is more common in children and the severe form can be associated with considerable morbidity. We report on 1.8 children with severe refractory atopic dermatitis who have been treated with cyclosporin on an open basis. The drug was given at an initial daily dose of 5 or 6 mg/kg and in some patients the dose was reduced according to response. Sixteen patients showed a good or excellent response to treatment, one a moderate response and one patient failed to improve. The treatment was well tolerated and there were no significant changes in serum creatinine or blood pressure. Long remission after withdrawal of treatment was seen in some patients, although most relapsed within a few weeks. We suggest that cyclosporin is an effective and safe short-term treatment for severe atopic dermatitis in childhood. [ABSTRACT FROM AUTHOR]

We report a case of severe chloracne, with systemic involvement, following occupational exposure to dihydrotrifluoromethylphenyl benzothiopyranopyrazolone, which, to our knowledge, has not been previously reported as a cause of chloracne. Aggressive drug treatment, including high-dose oral isotretinoin was of limited benefit in suppressing the disease activity. [ABSTRACT FROM AUTHOR]

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Morpheaform basal cell carcinoma (BCC) can cause diagnostic difficulty due to an atypical clinical presentation. Successful treatment requires a high index of clinical suspicion together with an early confirmatory biopsy. We present the case of an 81-year-old lady with a delayed diagnosis of morphoeic BCC due to an unusual presentation of evolving lid malposition, and we highlight the limitations of a punch biopsy in diagnosing atypical lesions. An appropriate biopsy technique is vital, with consideration for repeat biopsies when necessary, especially if the clinical picture is changing over time. [ABSTRACT FROM AUTHOR]

Vanadium carbide is known, for its hardness and other unique properties, as a refractory material. The synthesis of vanadium carbide is always associated with the utilization of expensive active metals, such as aluminum, calcium and magnesium, as a reducing agent to extract the vanadium metal from its corresponding oxide, followed by carbidization. The carbidization of reduced vanadium requires a complicated process and elevated temperature. Mechanical activation to synthesize vanadium carbide from its corresponding oxide and carbon source represents a promising, straightforward and less energy-intensive route. In the present study, vanadium carbide is synthesized by the carbothermic reduction of a mechanically activated mixture of V2O5 and carbon black as reducing agents without any additives. The reduction process is monitored by means of thermogravimetric analysis. The reduction products are characterized by X-ray diffraction and field emission scanning electron microscope. It is found that V8C7 with an average crystallite size of 88 nm can be synthesized from a V2O5-C mixture after milling for 15 h and further heating at 1050 °C for 1 h in an inert atmosphere. [ABSTRACT FROM AUTHOR]

Colloid degeneration is a rare but well-recognized entity, usually occurring on chronically sun-exposed skin. We report a case occurring on penile skin with no history of such exposure. [ABSTRACT FROM AUTHOR]

Treatment of trigeminal trophic syndrome is challenging and often unsatisfactory, particularly in patients with cognitive impairment. We report the novel use of a thermoplastic dressing in two patients with trigeminal trophic syndrome. Use of the dressing resulted in successful healing of ulceration in both patients, which has been maintained in the short term, representing a simple and economical therapeutic option in the management of this difficult condition. [ABSTRACT FROM AUTHOR]

The V-beam pulsed-dye laser (PDL) (595 nm) has gained popularity in the treatment of port wine stains (PWS). It uses longer pulse durations than the standard flashlamp-pumped pulsed-dye laser (FPDL) (585 nm) and has an in-built cooling system to protect the epidermis. This should, theoretically, reduce the treatment-associated side effects, including discomfort. The aim of this questionnaire-based study was to confirm the clinical impression that V-beam PDL is well tolerated. The results were compared with a historical group of 62 PWS patients treated with FPDL. Fifty-one patients took part in the current study. Only 35.7% (vs. 81% in the historical comparison group) required topical anaesthetic prior to laser treatment. A shortening in the duration of bruising (8 vs. 10 days) and of symptoms such as burning and tightness (3 vs. 10 days) was recorded. Lifestyle change after treatment was recorded by fewer patients (39 vs. 57%). We conclude that V-beam PDL is better tolerated than FPDL when used at therapeutic levels in patients with PWS. [ABSTRACT FROM AUTHOR]

Dermatomyositis (DM) is a connective tissue disorder characterized by cutaneous and muscle involvement. It is a well recognized paraneoplastic syndrome and has been linked with malignancy in 15-34% of adult patients1,2. The course of DM in such patients usually correlates closely with the activity of the underlying malignancy.3 We report a patient who developed DM 4 years after excision of a malignant melanoma (MM) from the back and 1 year before the diagnosis of metastatic disease. A literature review revealed that the association of dermatomyositis with MM is rare and consistent with a dismal prognosis. [ABSTRACT FROM AUTHOR]

We report a 22-year-old female with a 2-year history of increasingly numerous well-circumscribed, asymptomatic skin lesions. The clinical and histological features were consistent with anetoderma and investigations failed to reveal any associated underlying disorders. Electron microscopy of abnormal skin showed phagocytosis of elastic fibres by macrophages. Although the aetiology of primary anetoderma remains unknown, this finding suggests that phagocytic destruction of elastic fibres plays a major role in its pathogenesis. [ABSTRACT FROM AUTHOR]

Two epileptic patients developed an infectious mononucleosis-like illness which subsequently proved to be a carbamazepine-induced anticonvulsant hypersensitivity syndrome. Patch testing to carbamazepine 3 years later was positive in the one patient tested and negative in normal controls. The second patient died a few weeks alter the illness, secondary to long-standing cardiac disuse without having undergone patch testing. A skin biopsy was, however, consistent with an immune complex mediated drug reaction. Patch testing for systemically administered drugs is generally believed to be of little value in diagnosing drug allergies. However, we reinforce a previous suggestion that this investigation may be helpful in some cases of anticonvulsant hypersensitivity syndrome caused by carbamazepinet. The pathogenic role of type 3 and 4 hypersensitivity is also discussed. [ABSTRACT FROM AUTHOR]

Graft-versus-host disease (GVHD) is most commonly seen as a complication of bone marrow transplantation, although it can occur whenever tissue or blood products are given whereby immunologically competent donor lymphocytes react against host tissues. A 65-year-old man with non-Hodgkin's lymphoma developed a severe widespread erosive eruption of the skin and mucosal surfaces. Clinically and histologically it was identical to cutaneous GVHD even though the patient had never received tissue or blood products. He failed to respond to conventional therapy for GVHD, but his skin improved significantly on treating his underlying lymphoma, which eventually proved fatal. There are two previous reports of GVHD associated with malignancy but we believe this to be the first case secondary to a lymphoma. [ABSTRACT FROM AUTHOR]

We report the results of patch testing 85 patients with either long-standing venous ulceration or eczema complicating their leg ulcers. As previously reported, lanolin and its derivatives and topical antibiotics were the most frequent sensitizers. However, unlike previously published data, we found bacitracin to be the most potent sensitizer of all topical antiboitics tested. There were no positive reactions in a control group of patients, although we were unable to repeat the patch tests in patients with a positive reaction to bacitracin. In the past 10 years, our department has used a proprietary mixture of polymyxin and bacitracin in treating infected leg ulcers and other dermatoses. It is therefore possible that chronic usage of topical bacitracin on leg ulcers carries a significant risk of contact sensitization. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article related to the treatment of primary melanoma published in a previous issue of the periodical.

We report a 53-year-old patient with clinical features of pellagra as a complication of Crohn's disease. His symptoms improved rapidly on taking oral nicotinic acid and vitamin B complex. We suggest the paucity of reported cases of pellagra in Crohn's disease is a reflection of poor recognition of this complication. [ABSTRACT FROM PUBLISHER]