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1.
Chemosphere ; 339: 139717, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37541442

ABSTRACT

Access to clean water is the mandatory requirement for every living being to sustain life. So, membrane-based integrated approach of adsorption and separation technology has recently been preferred by scientists over other conventional techniques, for wastewater treatment. Current research focused on the synthesis of novel imidazolium (A1) based IL, which was further functionalized with hydroxyapatite (HAp; extracted from Labeo rohita scales), to create possible solutions towards environmental remediation. Cellulose acetate (CA) was used for the fabrication of three different ionic liquid membranes. All the synthesized products were characterized by FTIR, XRD and TGA. Two dyes of different nature, i.e., congo red (anionic) and crystal violet (cationic) were selected because of their highly toxic and carcinogenic effects, for batch adsorption experiments. Antibacterial activity of the synthesized membranes was also evaluated against S. aureus. Results of the study revealed that CA-HA1 1:2 acted as the best adsorbent towards the removal of crystal violet, exhibiting removal efficiency of 98% with the contact time of 24 h while in case of congo red adsorption, CA-HA1 (1:2) proved as prime adsorbent with the removal efficiency of 96% for the same preceding contact time. Considering the antibacterial character of the synthesized membranes, CA-A1 (1:1) emerged as very efficient antibacterial agent with the inhibition zone of 50 mm after 48 h. The overall behavior of monolayer and multilayer adsorption was witnessed for both dyes while kinetic studies favored the pseudo-second order reaction for all adsorbents.


Subject(s)
Environmental Pollutants , Ionic Liquids , Water Pollutants, Chemical , Congo Red , Ionic Liquids/toxicity , Kinetics , Durapatite , Gentian Violet/chemistry , Staphylococcus aureus , Coloring Agents/chemistry , Anti-Bacterial Agents/toxicity , Adsorption , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/chemistry , Hydrogen-Ion Concentration
2.
R Soc Open Sci ; 10(7): 230503, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37476508

ABSTRACT

In the present research, the structural, electronic and optical properties of transition metal dichalcogenide-doped transition metal oxides MoS2-doped-V2O5 with various doping concentrations (x = 1-3%) of MoS2 atoms are studied by using first principles calculation. The generalized gradient approximation Perdew-Burke-Ernzerhof simulation approach is used to investigate the energy bandgap (Eg) of orthorhombic structures. We examined the energy bandgap (Eg) decrement from 2.76 to 1.30 eV with various doping (x = 1-3%) of molybdenum disulfide (MoS2) atoms. The bandgap nature shows that the material is a well-known direct bandgap semiconductor. MoS2 doping (x = 1-3%) atoms in pentoxide (V2O5) creates the extra gamma active states which contribute to the formation of conduction and valance bands. MoS2-doped-V2O5 composite is a proficient photocatalyst, has a large surface area for absorption of light, decreases the electron-hole pairs recombination rate and increases the charge transport. A comprehensive study of optical conductivity reveals that strong peaks of MoS2-doped-V2O5 increase in ultraviolet spectrum region with small shifts at larger energy bands through increment doping x = 1-3% atoms of MoS2. A significant decrement was found in the reflectivity due to the decrement in the bandgap with doping. The optical properties significantly increased by the decrement of bandgap (Eg). Two-dimensional MoS2-doped-V2O5 composite has high energy absorption, optical conductivity and refractive index, and is an appropriate material for photocatalytic applications.

4.
Materials (Basel) ; 15(5)2022 Feb 24.
Article in English | MEDLINE | ID: mdl-35268931

ABSTRACT

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.

5.
ACS Omega ; 6(15): 10250-10259, 2021 Apr 20.
Article in English | MEDLINE | ID: mdl-34056179

ABSTRACT

The efficacy of LaNaTaO3 perovskites decoration RuO2 at diverse contents for the photocatalytic H2 generation has been explored in this study. The photocatalytic performance of RuO2 co-catalyst onto mesoporous LaNaTaO3 was evaluated for H2 under UV illumination. 3%RuO2/LaNaTaO3 perovskite photocatalyst revealed the highest photocatalytic H2 generation performance, indicating that RuO2 nanoparticles could promote the photocatalytic efficiency of LaNaTaO3 perovskite significantly. The H2 evolution rate of 3%RuO2/LaNaTaO3 perovskite is 11.6 and 1.3 times greater than that of bare LaNaTaO3 perovskite employing either 10% CH3OH or pure H2O, respectively. Interestingly, the photonic efficiency of 3%RuO2/LaNaTaO3 perovskite was enhanced 10 times than LaNaTaO3 perovskite in the presence of aqueous CH3OH solutions as a hole sacrificial agent. The high separation of charge carriers is interpreted by the efficient hole capture using CH3OH, hence leading to greater H2 generation over RuO2/LaNaTaO3 perovskites. This is attributed to an adjustment position between recombination electron-hole pairs and also the reduction of potential conduction alignment as a result of RuO2 incorporation. The suggested mechanisms of RuO2/LaNaTaO3 perovskites for H2 generation employing either CH3OH or pure H2O were discussed. The photocatalytic performances of the perovskite photocatalyst were elucidated according to the PL intensity and the photocurrent response investigations.

6.
Materials (Basel) ; 15(1)2021 12 22.
Article in English | MEDLINE | ID: mdl-35009202

ABSTRACT

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 ΔEcrystal, exchange energies Δx(d), Δx (pd) and exchange constants (Noα and Noß). 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.

7.
Materials (Basel) ; 13(19)2020 Oct 02.
Article in English | MEDLINE | ID: mdl-33023271

ABSTRACT

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.

8.
Orbit ; 27(3): 183-5, 2008.
Article in English | MEDLINE | ID: mdl-18569825

ABSTRACT

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.


Subject(s)
Carcinoma, Basal Cell/pathology , Ectropion/pathology , Entropion/pathology , Eyelid Neoplasms/pathology , Aged, 80 and over , Biopsy, Needle , Carcinoma, Basal Cell/diagnosis , Carcinoma, Basal Cell/surgery , Diagnosis, Differential , Ectropion/diagnosis , Ectropion/surgery , Entropion/diagnosis , Entropion/surgery , Eyelid Neoplasms/diagnosis , Eyelid Neoplasms/surgery , Female , Follow-Up Studies , Humans , Immunohistochemistry , Mohs Surgery , Plastic Surgery Procedures/methods , Risk Assessment , Surgical Flaps , Treatment Outcome
9.
Br J Dermatol ; 155(5): 1029-36, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17034536

ABSTRACT

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 1,501 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.


Subject(s)
Cryosurgery/methods , Keratosis/drug therapy , Photochemotherapy/methods , Photosensitivity Disorders/drug therapy , Aged , Aged, 80 and over , Aminolevulinic Acid/adverse effects , Aminolevulinic Acid/analogs & derivatives , Aminolevulinic Acid/therapeutic use , Cryosurgery/adverse effects , Esthetics , Facial Dermatoses/drug therapy , Facial Dermatoses/surgery , Female , Humans , Keratosis/pathology , Keratosis/surgery , Male , Middle Aged , Patient Satisfaction , Photochemotherapy/adverse effects , Photosensitivity Disorders/pathology , Photosensitivity Disorders/surgery , Photosensitizing Agents/adverse effects , Photosensitizing Agents/therapeutic use , Scalp Dermatoses/drug therapy , Scalp Dermatoses/surgery , Severity of Illness Index
10.
Clin Exp Dermatol ; 31(5): 674-6, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16901308

ABSTRACT

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.


Subject(s)
Mucins/metabolism , Penile Diseases/pathology , Skin Diseases/pathology , Adult , Colloids/metabolism , Elastic Tissue/pathology , Humans , Male
11.
Clin Exp Dermatol ; 31(4): 525-7, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16716154

ABSTRACT

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.


Subject(s)
Bandages , Skin Ulcer/therapy , Wound Healing , Aged, 80 and over , Female , Humans , Hypesthesia/etiology , Male , Middle Aged , Neurosurgical Procedures/adverse effects , Nose , Postoperative Complications , Skin Ulcer/etiology , Syndrome , Trigeminal Nerve Injuries , Trigeminal Neuralgia/surgery
13.
Lasers Med Sci ; 20(3-4): 114-6, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16047083

ABSTRACT

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.


Subject(s)
Low-Level Light Therapy/adverse effects , Pain/etiology , Port-Wine Stain/radiotherapy , Skin Diseases/etiology , Adolescent , Adult , Aged , Anesthetics, Local , Child , Female , Humans , Male , Middle Aged , Pain/psychology , Quality of Life , Skin Diseases/psychology , Social Behavior , Surveys and Questionnaires , Time Factors
15.
Br J Dermatol ; 142(1): 66-71, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10651696

ABSTRACT

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.


Subject(s)
Computer-Assisted Instruction/methods , Melanoma/diagnosis , Patient Education as Topic/methods , Adolescent , Adult , Aged , Analysis of Variance , Anxiety/etiology , Humans , Middle Aged , Prospective Studies
16.
Br J Dermatol ; 141(2): 279-82, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10468800

ABSTRACT

An increasingly important approach to the management of patients with severe psoriasis is the concurrent use of two systemic treatments. Previous guidelines have advised against the use of methotrexate and cyclosporin in combination. We report the successful use of a combination of methotrexate and cyclosporin in the treatment of 19 patients with severe, recalcitrant psoriasis, 15 of whom had psoriatic arthropathy. Most patients had previously received two or more systemic treatments. Before combination treatment was started nine of the patients were taking methotrexate and 10 were taking cyclosporin at the maximum tolerated doses. The duration of combination treatment was bimodally distributed, with seven patients having short-term treatment (mean +/- SD duration 18. 9 +/- 15.7 weeks) and 12 patients having long-term treatment (mean +/- SD duration 193.2 +/- 160.6 weeks). Those patients who received short-term treatment did not develop any evidence of toxicity from either agent. Of those patients on long-term treatment, three developed mild impairment of renal function that returned to normal following a reduction in dose of cyclosporin, and three had impairment of renal function (following long-term cyclosporin monotherapy) that improved, but did not normalize, following a reduction in dose of cyclosporin. In each case, combination treatment for psoriasis resulted in good control of both skin and joint problems using lower doses of each agent than would have been used for monotherapy. We conclude that the combination of methotrexate and cyclosporin is an effective treatment for this group of patients.


Subject(s)
Cyclosporine/administration & dosage , Dermatologic Agents/administration & dosage , Methotrexate/administration & dosage , Psoriasis/drug therapy , Adult , Chronic Disease , Cyclosporine/adverse effects , Drug Therapy, Combination , Female , Humans , Male , Methotrexate/adverse effects , Middle Aged , Retrospective Studies
17.
Br J Dermatol ; 137(4): 609-13, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9390341

ABSTRACT

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 x 10(9)/L vs. 332 x 10(9)/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.


Subject(s)
Hematologic Neoplasms/complications , Paraneoplastic Syndromes/etiology , Sweet Syndrome/etiology , Adolescent , Adult , Age Factors , Aged , Anemia/complications , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Paraneoplastic Syndromes/drug therapy , Paraneoplastic Syndromes/pathology , Platelet Count , Retrospective Studies , Risk Factors , Sex Factors , Sweet Syndrome/drug therapy , Sweet Syndrome/pathology
18.
Br J Dermatol ; 137(1): 137-9, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9274642

ABSTRACT

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.


Subject(s)
Graft vs Host Disease/complications , Lymphoma, B-Cell/complications , Skin Diseases/complications , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cyclophosphamide/administration & dosage , Graft vs Host Disease/drug therapy , Graft vs Host Disease/pathology , Humans , Lip , Lymphoma, B-Cell/drug therapy , Lymphoma, B-Cell/pathology , Male , Prednisone/administration & dosage , Prednisone/analogs & derivatives , Skin Diseases/drug therapy , Skin Diseases/pathology , Vincristine/administration & dosage
19.
Br J Dermatol ; 135 Suppl 48: 21-4, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8881900

ABSTRACT

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 18 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.


Subject(s)
Cyclosporine/therapeutic use , Dermatitis, Atopic/drug therapy , Dermatologic Agents/therapeutic use , Adolescent , Child , Child, Preschool , Creatinine/blood , Humans , Recurrence , Treatment Outcome
20.
Clin Exp Dermatol ; 21(5): 334-7, 1996 Sep.
Article in English | MEDLINE | ID: mdl-9136150

ABSTRACT

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.


Subject(s)
Carcinoma, Squamous Cell/complications , Vulvar Neoplasms/complications , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/pathology , Female , Humans , In Situ Hybridization , Lichen Planus/complications , Lichen Planus/pathology , Lichen Sclerosus et Atrophicus/complications , Lichen Sclerosus et Atrophicus/pathology , Middle Aged , Papillomaviridae/isolation & purification , Papillomavirus Infections/complications , Papillomavirus Infections/pathology , Skin Diseases/complications , Skin Diseases/pathology , Tumor Virus Infections/complications , Tumor Virus Infections/pathology , Vulvar Neoplasms/pathology
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