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1.
Cureus ; 16(1): e52519, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38371057

ABSTRACT

Common peroneal neuropathy (CPN), also known as Slimmer's Palsy, is an isolated peripheral neuropathy typically associated with rapid weight loss resulting in loss of adipose tissue and subsequent nerve compression at the fibular head and is up to three times more common in individuals with malignancy. In this case report, we describe the diagnosis of CPN in a 54-year-old female with a 2.5-month history of atraumatic left foot drop and left ankle paresthesias, preceded by a 35-40 pound weight loss over the prior 3.5 month period in the setting of metastatic breast cancer.

2.
Front Chem ; 10: 835832, 2022.
Article in English | MEDLINE | ID: mdl-35494625

ABSTRACT

Metal sulphides, including zinc sulphide (ZnS), are semiconductor photocatalysts that have been investigated for the photocatalytic degradation of organic pollutants as well as their activity during the hydrogen evolution reaction and water splitting. However, devising ZnS photocatalysts with a high overall quantum efficiency has been a challenge due to the rapid recombination rates of charge carriers. Various strategies, including the control of size and morphology of ZnS nanoparticles, have been proposed to overcome these drawbacks. In this work, ZnS samples with different morphologies were prepared from zinc and sulphur powders via a facile hydrothermal method by varying the amount of sodium borohydride used as a reducing agent. The structural properties of the ZnS nanoparticles were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques. All-electron hybrid density functional theory calculations were employed to elucidate the effect of sulphur and zinc vacancies occurring in the bulk as well as (220) surface on the overall electronic properties and absorption of ZnS. Considerable differences in the defect level positions were observed between the bulk and surface of ZnS while the adsorption of NaBH4 was found to be highly favourable but without any significant effect on the band gap of ZnS. The photocatalytic activity of ZnS was evaluated for the degradation of rhodamine B dye under UV irradiation and hydrogen generation from water. The ZnS nanoparticles photo-catalytically degraded Rhodamine B dye effectively, with the sample containing 0.01 mol NaBH4 being the most efficient. The samples also showed activity for hydrogen evolution, but with less H2 produced compared to when untreated samples of ZnS were used. These findings suggest that ZnS nanoparticles are effective photocatalysts for the degradation of rhodamine B dyes as well as the hydrogen evolution, but rapid recombination of charge carriers remains a factor that needs future optimization.

3.
Sci Rep ; 12(1): 2693, 2022 02 17.
Article in English | MEDLINE | ID: mdl-35177739

ABSTRACT

The global pandemic response to COVID-19 has led to the generation of huge volumes of unrecyclable plastic waste from single use disposable face coverings. Rotary hearth furnaces can be used to recover Zn and Fe from non-recyclable steelmaking by-product dusts, and waste plastic material such as facemasks could be utilized as a supplementary reductant for the rotary hearth furnace (RHF), but their fibrous form makes milling and processing to appropriate sizing for RHF application extremely challenging. A scalable method of grinding facemasks to powder by melting and mixing with Welsh coal dust reported herein provides a solution to both environmental challenges. The melt-blended PPE/coal dust shows a dramatically improved CO2 gasification reactivity (Ea = 133-159 kJmol-1) when compared to the untreated coal (Ea = 183-246 kJmol-1), because of improved pore development in the coal during the pyrolysis stage of heating and the catalytic activity of the CaO based ash present in the facemask plastic. The results are promising for the application of waste facemasks in recycling steelmaking by-product dusts in rotary hearth furnaces and may also be suitable for direct injection to the blast furnace subject to further study.


Subject(s)
Coal Industry , Masks , Metallurgy , Recycling/methods , Waste Management/methods
4.
Membranes (Basel) ; 10(5)2020 May 23.
Article in English | MEDLINE | ID: mdl-32456208

ABSTRACT

A 316-grade woven stainless-steel mesh membrane was investigated as a gas-separation membrane for alkaline water-splitting electrolysis. Its resistance was measured using electrochemical impedance spectroscopy (EIS) and linear sweep voltammetry (LSV), with the conclusion that it presented approximately half the resistance of a comparable commercial alternative (ZirfonTM). Its gas-separation performance was analysed using gas chromatography (GC) at 140 mA cm-2, where it achieved 99.25% purity at the hydrogen outlet of the electrolyser. This fell to 97.5% under pumped circulation, which highlights that it is sensitive to pressure differentials. Nevertheless, this mixture is still more than a factor two inside the upper flammability limit of hydrogen in oxygen. It is hoped that such a low-cost material may bring entry-level electrolysis to many hitherto discounted applications.

5.
Sci Rep ; 9(1): 11573, 2019 Aug 09.
Article in English | MEDLINE | ID: mdl-31399632

ABSTRACT

Through a facile solvothermal procedure, a CdS/WOx nanocomposite has been synthesised which exhibits photocapacitive behaviour under white light illumination at a radiant flux density of 99.3 mW cm-2. Photoelectrochemical experiments were undertaken to examine the self-charging properties of the material and to develop an understanding of the underlying electronic band structure responsible for the phenomenon. By employing XPS, UPS and UV-Vis diffuse reflectance spectroscopy for further characterisation, the ability of the composite to generate current following the removal of incident light was related to the trapping of photoexcited electrons by the WOx component. The presence of WOx yielded an order of magnitude increase in the transient photocurrent response relative to CdS alone, an effect attributed to the suppression of electron-hole recombination in CdS due to hole transfer across the CdS/WOx interface. Moreover, current discharge from the material persisted for more than twenty minutes after final illumination, an order of magnitude improvement over many existing binary composites. As a seminal investigation into the photocapacitive characteristics of CdS/WOx composites, the work offers insight into how the constituent materials might be utilised as part of a future self-charging solar device.

6.
ACS Appl Mater Interfaces ; 7(16): 8667-76, 2015 Apr 29.
Article in English | MEDLINE | ID: mdl-25853179

ABSTRACT

Harvesting radiant energy to trigger water photoelectrolysis and produce clean hydrogen is receiving increasing attention in the search of alternative energy resources. In this regard, hematite (α-Fe2O3) nanostructures with controlled nano-organization have been fabricated and investigated for use as anodes in photoelectrochemical (PEC) cells. The target systems have been grown on conductive substrates by plasma enhanced-chemical vapor deposition (PE-CVD) and subjected to eventual ex situ annealing in air to further tailor their structure and properties. A detailed multitechnique approach has enabled to elucidate the interrelations between system characteristics and the generated photocurrent. The present α-Fe2O3 systems are characterized by a high purity and hierarchical morphologies consisting of nanopyramids/organized dendrites, offering a high contact area with the electrolyte. PEC data reveal a dramatic response enhancement upon thermal treatment, related to a more efficient electron transfer. The reasons underlying such a phenomenon are elucidated and discussed by transient absorption spectroscopy (TAS) studies of photogenerated charge carrier kinetics, investigated on different time scales for the first time on PE-CVD Fe2O3 nanostructures.

7.
J Nanosci Nanotechnol ; 11(9): 8126-31, 2011 Sep.
Article in English | MEDLINE | ID: mdl-22097541

ABSTRACT

Thin films of thermochromic vanadium dioxide have been deposited on glass substrates at 530 degrees C from the aerosol assisted chemical vapour deposition of vanadyl acetylacetonate solutions in ethanol under the influence of electric fields. Electric fields were generated by applying a potential difference between the top plate and the substrate of the reactor. The deposited films were analysed and characterised using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and variable temperature UV/Visible spectroscopy. The application of an electric field led to significant changes in the deposited films microstructure and functional properties. It was found that an increase in electric field strength caused a decrease in crystallite size and in an increase in the change in transmission in the near infrared when compared to films grown without the use of an electric field.

8.
J Nanosci Nanotechnol ; 11(9): 8158-62, 2011 Sep.
Article in English | MEDLINE | ID: mdl-22097547

ABSTRACT

Thin films of thermochromic vanadium dioxide have been the subject of intensive research in recent years year due to their postulated use as "intelligent" window coatings. The usefulness of such technology depends on a semi-conducting to metal transition with an associated change in infra-red optical properties. This exact nature of this transition depends on a large number of factors such as doping, crystallite size, strain, crystallographic orientation etc. In this paper we discuss the nature of these factors with a particular focus on how the application of electric fields in the deposition affects crystallite size and film strain with reference to recent results.

9.
Curr Med Res Opin ; 24(4): 1231-5, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18355422

ABSTRACT

OBJECTIVE: Rosuvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor used for the treatment of dyslipidaemia, may be co-administered with antacids in clinical practice. This trial assessed the effect of simultaneous and separated administration of an antacid preparation containing aluminium hydroxide 220 mg/5 mL and magnesium hydroxide 195 mg/5 mL (co-magaldrox 195/220) on the pharmacokinetics of rosuvastatin. RESEARCH DESIGN AND METHODS: A randomised, open-label, three-way crossover trial was performed. Healthy male volunteers (n = 14) received a single dose of rosuvastatin 40 mg alone, rosuvastatin 40 mg plus 20 mL antacid suspension taken simultaneously, and rosuvastatin 40 mg plus 20 mL antacid suspension taken 2 h after rosuvastatin on three separate occasions with a washout of > or = 7 days between each. MAIN OUTCOME MEASURES: The primary parameters were area under the rosuvastatin plasma concentration-time curve from time zero to the last quantifiable concentration (AUC(0-t)) and maximum observed rosuvastatin plasma concentration (C(max)) in the absence and presence of antacid. RESULTS: When rosuvastatin and antacid were given simultaneously, the antacid reduced the rosuvastatin AUC(0-t) by 54% (90% confidence interval [CI] for the treatment 0.40-0.53) and C(max) by 50% (90% CI 0.41-0.60). When the antacid was given 2 h after rosuvastatin, the antacid reduced the rosuvastatin AUC(0-t) by 22% (90% CI 0.68-0.90) and the C(max) by 16% (90% CI 0.70-1.01). The effect of repeated antacid administration was not studied and it cannot be discounted that this may have resulted in a stronger interaction than that observed here. CONCLUSIONS: Simultaneous dosing with rosuvastatin and antacid resulted in a decrease in rosuvastatin systemic exposure of approximately 50%. This effect was mitigated when antacid was administered 2 h after rosuvastatin.


Subject(s)
Aluminum Hydroxide/adverse effects , Antacids/adverse effects , Anticholesteremic Agents/pharmacokinetics , Fluorobenzenes/pharmacokinetics , Magnesium Hydroxide/adverse effects , Pyrimidines/pharmacokinetics , Sulfonamides/pharmacokinetics , Adult , Aluminum Hydroxide/administration & dosage , Antacids/administration & dosage , Anticholesteremic Agents/administration & dosage , Area Under Curve , Biological Availability , Cross-Over Studies , Drug Administration Schedule , Drug Interactions , Fluorobenzenes/administration & dosage , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacokinetics , Magnesium Hydroxide/administration & dosage , Male , Middle Aged , Pyrimidines/administration & dosage , Rosuvastatin Calcium , Sulfonamides/administration & dosage , Time Factors
10.
J Pharm Biomed Anal ; 35(3): 609-14, 2004 May 28.
Article in English | MEDLINE | ID: mdl-15137986

ABSTRACT

A selective, accurate and precise assay was developed for the quantification in human plasma of the N-desmethyl metabolite of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor rosuvastatin. The assay-employing automated SPE followed by HPLC with positive ion electrospray tandem MS (HPLC-MS/MS)-was validated. The standard curve range for N-desmethyl rosuvastatin in human plasma was 0.5-30 ng/ml with 0.5 ng/ml being the limit of quantification. Plasma samples were mixed 1:1 with sodium acetate buffer (pH 4.0; 0.1M) soon after separation from red blood cells. N-Desmethyl rosuvastatin was stable in plasma:buffer at room temperature for 24h and at -70 degrees C for 12 months. The assay was applied successfully to the quantification of N-desmethyl rosuvastatin in human plasma following administration of rosuvastatin.


Subject(s)
Fluorobenzenes/blood , Pyrimidines/blood , Spectrometry, Mass, Electrospray Ionization/methods , Sulfonamides/blood , Chromatography, High Pressure Liquid/methods , Drug Stability , Fluorobenzenes/chemistry , Fluorobenzenes/metabolism , Gas Chromatography-Mass Spectrometry , Humans , Pyrimidines/chemistry , Pyrimidines/metabolism , Rosuvastatin Calcium , Sulfonamides/chemistry , Sulfonamides/metabolism
11.
Clin Ther ; 25(2): 459-71, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12749507

ABSTRACT

BACKGROUND: Rosuvastatin and fenofibrate are lipid-regulating agents with different modes of action. Patients with dyslipidemia who have not achieved treatment targets with monotherapy may benefit from the combination of these agents. OBJECTIVE: The effect of coadministration of rosuvastatin and fenofibrate on the steady-state pharmacokinetics of rosuvastatin and fenofibric acid (the active metabolite of fenofibrate) was assessed in healthy volunteers. METHODS: This was an open-label, randomized, 3-way crossover trial consisting of three 7-day treatment periods. Healthy male volunteers received one of the following treatment regimens in each period: rosuvastatin 10 mg orally once daily; fenofibrate 67 mg orally TID; and rosuvastatin + fenofibrate dosed as above. The steady-state pharmacokinetics of rosuvastatin and fenofibric acid, both as substrate and as interacting drug, were investigated on day 7 of dosing. Treatment effects were assessed by construction of 90% CIs around the ratios of the geometric least-square means for rosuvastatin + fenofibrate/rosuvastatin and rosuvastatin + fenofibrate/fenofibrate for the area under the plasma concentration-time curve (AUC) and maximum plasma concentration (derived from analysis of variance of log-transformed parameters). RESULTS: Fourteen healthy male volunteers participated in the study. When rosuvastatin was coadministered with fenofibrate, there were minor increases in the AUC from 0 to 24 hours and maximum concentration (Cmax) of rosuvastatin: the respective geometric least-square means increased by 7% (90% CI, 1.00-1.15) and 21% (90% CI, 1.14-1.28). The pharmacokinetic parameters of fenofibric acid were similar when fenofibrate was dosed alone and with rosuvastatin: the geometric least-square means for fenofibric acid AUC from 0 to 8 hours and Cmax decreased by 4% (90% CI, 0.90-1.02) and 9% (90% CI, 0.84-1.00), respectively. The treatments were well tolerated alone and in combination. CONCLUSION: Coadministration of rosuvastatin and fenofibrate produced minimal changes in rosuvastatin and fenofibric acid exposure.


Subject(s)
Fenofibrate/analogs & derivatives , Fenofibrate/metabolism , Fenofibrate/pharmacokinetics , Fluorobenzenes/pharmacokinetics , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacokinetics , Hypolipidemic Agents/pharmacokinetics , Pyrimidines , Sulfonamides , Adult , Area Under Curve , Cross-Over Studies , Drug Interactions , Fenofibrate/blood , Fluorobenzenes/blood , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/blood , Hypolipidemic Agents/blood , Male , Middle Aged , Rosuvastatin Calcium , Time Factors
12.
Biol Psychiatry ; 53(7): 627-9, 2003 Apr 01.
Article in English | MEDLINE | ID: mdl-12679243

ABSTRACT

BACKGROUND: A high incidence of schizophrenia has been reported in individuals with sex chromosome aneuploides (SCAs), and extra-X aneuploidy appears to adversely affect neurodevelopment. We previously examined neurodevelopment in SCA subjects with structural magnetic resonance imaging (MRI) of the brain. We present an XXY subject who subsequently developed schizophrenia. Further examination of the MRI data was undertaken. METHODS: Graphs of MRI-determined regional brain to whole brain volume proportions and cerebral asymmetry indexes were generated for Klinefelter (n = 10) and male control subjects (n = 25) to allow inter-individual comparisons. RESULTS: The index case had reversed prefrontal and temporal lobe asymmetries, and these findings were more marked than in any other subject. CONCLUSIONS: It has been suggested that a genetic locus for schizophrenia may be found on the X chromosome and that the gene(s) concerned are implicated in the development of normal cerebral asymmetries. This case supports these arguments.


Subject(s)
Klinefelter Syndrome/pathology , Prefrontal Cortex/abnormalities , Schizophrenia/pathology , Temporal Lobe/abnormalities , Adolescent , Humans , Klinefelter Syndrome/complications , Magnetic Resonance Imaging , Male , Schizophrenia/complications , Scotland
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