181 research outputs found
The physicochemical investigation of hydrothermally reduced textile waste and application within carbon-based electrodes.
From Europe PMC via Jisc Publications RouterHistory: ppub 2019-04-01, epub 2019-04-10Publication status: PublishedTextile waste is on the rise due to the expanding global population and the fast fashion market. Large volumes of textile waste are increasing the need for new methods for recycling mixed fabric materials. This paper employs a hydrothermal conversion route for a polyester/cotton mix in phosphoric acid to generate carbon materials (hydrochars) for electrochemical applications. A combination of characterization techniques revealed the reaction products were largely comprised of two major components. The first is a granular material with a surface C : O ratio of 2 : 1 interspersed with phosphorous and titanium proved using energy dispersive X-ray spectroscopy, and the other is a crystalline material with a surface C : O ratio of 3 : 2 containing no phosphorous or titanium. The latter material was found via X-ray diffraction and differential scanning calorimetry to be terephthalic acid. Electrochemical experiments conducted using the hydrochar as a carbon paste electrode demonstrates an increase in current response compared to carbon reference materials. The improved current responses, intrinsically related to the surface area of the material, could be beneficial for electrochemical sensor applications, meaning that this route holds promise for the development of a cheap recycled carbon material, using straightforward methods and simple laboratory reagents
Production of hybrid macro/micro/nano surface structures on Ti6Al4V surfaces by picosecond laser surface texturing and their antifouling characteristics
The development of surfaces which reduce biofouling has attracted much interest in practical applications. Three picosecond laser generated surface topographies (Ti1, Ti2, Ti3) on titanium were produced, treated with fluoroalkylsilane (FAS), then characterised using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Raman Spectroscopy, Fourier Transform Infra-Red (FTIR) spectroscopy, contact angle measurements and white light interference microscopy. The surfaces had a range of different macro/micro/nano topographies. Ti2 had a unique, surface topography with large blunt conical peaks and was predominantly a rutile surface with closely packed, self-assembled FAS; this was the most hydrophobic sample (water contact angle 160°; ΔGiwi was −135.29 mJ m−2). Bacterial attachment, adhesion and retention to the surfaces demonstrated that all the laser generated surfaces retained less bacteria than the control surface. This also occurred following the adhesion and retention assays when the bacteria were either not rinsed from the surfaces or were retained in static conditions for one hour. This work demonstrated that picosecond laser generated surfaces may be used to produce antiadhesive surfaces that significantly reduced surface fouling. It was determined that a tri-modally dimensioned surface roughness, with a blunt conical macro-topography, combined with a close-packed fluoroalkyl monolayer was required for an optimised superhydrophobic surface. These surfaces were effective even following surface immersion and static conditions for one hour, and thus may have applications in a number of food or medical industries
Executive Summary of the American Radium Society Appropriate Use Criteria for Radiation Treatment of Node-Negative Muscle Invasive Bladder Cancer
PURPOSE: Definitive radiation therapy (RT), with or without concurrent chemotherapy, is an alternative to radical cystectomy for patients with localized, muscle-invasive bladder cancer (MIBC) who are either not surgical candidates or prefer organ preservation. We aim to synthesize an evidence-based guideline regarding the appropriate use of RT.
METHODS AND MATERIALS: We performed a Preferred Reporting Items for Systematic Reviews and Meta-analyses literature review using the PubMed and Embase databases. Based on the literature review, critical management topics were identified and reformulated into consensus questions. An expert panel was assembled to address key areas of both consensus and controversy using the modified Delphi framework.
RESULTS: A total of 761 articles were screened, of which 61 were published between 1975 and 2019 and included for full review. There were 7 well-designed studies, 20 good quality studies, 28 quality studies with design limitations, and 6 references not suited as primary evidence. Adjuvant radiation therapy after cystectomy was not included owing to lack of high-quality data or clinical use. An expert panel consisting of 14 radiation oncologists, 1 medical oncologist, and 1 urologist was assembled. We identified 4 clinical variants of MIBC: surgically fit patients who wish to pursue organ preservation, patients surgically unfit for cystectomy, patients medically unfit for cisplatin-based chemotherapy, and borderline cystectomy candidates based on age with unilateral hydronephrosis and normal renal function. We identified key areas of controversy, including use of definitive radiation therapy for patients with negative prognostic factors, appropriate radiation therapy dose, fractionation, fields and technique when used, and chemotherapy sequencing and choice of agent.
CONCLUSIONS: There is limited level-one evidence to guide appropriate treatment of MIBC. Studies vary significantly with regards to patient selection, chemotherapy use, and radiation therapy technique. A consensus guideline on the appropriateness of RT for MIBC may aid practicing oncologists in bridging the gap between data and clinical practice
Propagation of Epileptiform Events across the Corpus Callosum in a Cingulate Cortical Slice Preparation
We report on a novel mouse in vitro brain slice preparation that contains intact callosal axons connecting anterior cingulate cortices (ACC). Callosal connections are demonstrated by the ability to regularly record epileptiform events between hemispheres (bilateral events). That the correlation of these events depends on the callosum is demonstrated by the bisection of the callosum in vitro. Epileptiform events are evoked with four different methods: (1) bath application of bicuculline (a GABA-A antagonist); (2) bicuculline+MK801 (an NMDA receptor antagonist), (3) a zero magnesium extracellular solution (0Mg); (4) focal application of bicuculline to a single cortical hemisphere. Significant increases in the number of epileptiform events, as well as increases in the ratio of bilateral events to unilateral events, are observed during bath applications of bicuculline, but not during applications of bicuculline+MK-801. Long ictal-like events (defined as events >20 seconds) are only observed in 0Mg. Whole cell patch clamp recordings of single neurons reveal strong feedforward inhibition during focal epileptiform events in the contralateral hemisphere. Within the ACC, we find differences between the rostral areas of ACC vs. caudal ACC in terms of connectivity between hemispheres, with the caudal regions demonstrating shorter interhemispheric latencies. The morphologies of many patch clamped neurons show callosally-spanning axons, again demonstrating intact callosal circuits in this in vitro preparation
Next Generation Additive Manufacturing: Tailorable Graphene/Polylactic(acid) Filaments Allow the Fabrication of 3D Printable Porous Anodes for Utilisation within Lithium-Ion Batteries
This is the peer reviewed version of the following article: Foster, C. W., Zou, G., Jiang, Y., Down, M. P., Liauw, C. M., Ferrari, A. G., Ji, X., Smith, G. C., Kellyand, P. J., Banks, C. E. (2019). Next Generation Additive Manufacturing: Tailorable Graphene/Polylactic(acid) Filaments Allow the Fabrication of 3D Printable Porous Anodes for Utilisation within Lithium-Ion Batteries. Batteries & Supercaps., 2(5), 448-453, which has been published in final form at https://doi.org/10.1002/batt.201800148. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingHerein, we report the fabrication and application of Li-ion anodes for utilisation within Li-ion batteries, which are fabricated via additive manufacturing/3D printing (fused depo- sition modelling) using a bespoke graphene/polylactic acid (PLA) filament, where the graphene content can be readily tailored and controlled over the range 1–40 wt. %. We demon- strate that a graphene content of 20 wt. % exhibits sufficient conductivity and critically, effective 3D printability for the rapid manufacturing of 3D printed freestanding anodes (3DAs); simplifying the components of the Li-ion battery negating the need for a copper current collector. The 3DAs are physicochemcally and electrochemically characterised and possess sufficient conductivity for electrochemical studies. Critically, it is found that if the 3DAs are used in Li-ion batteries the specific capacity is very poor but can be significantly improved through the use of a chemical pre-treatment. Such treatment induces an increased porosity, which results in a 200-fold increase (after anode stabilisation) of the specific capacity (ca. 500 mAhg-1 at a current density of 40 mAg-1). This work significantly enhances the field of additive manufacturing/3D printed graphene based energy storage devices demonstrating that useful 3D printable batteries can be realise
Antimicrobial activity of graphene oxide-metal hybrids.
With resistant bacteria on the increase, there is a need for new combinations of antimicrobials/biocidal agents to help control the transmission of such microorganisms. Particulate forms of graphite, graphene oxide (GO) and metal-hybrid compounds (silver-graphene oxide (AgGO) and zinc oxide graphene oxide (ZnOGO)) were fabricated and characterised. X-Ray diffraction and Diffuse Reflectance Infrared Fourier Transform Spectroscopy demonstrated the composition of the compounds. Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy determined the compounds were heterogeneous and irregular in shape and size and that the level of silver in the AgGO sample was 57.9 wt% and the ZnOGO contained 72.65 wt % zinc. The compounds were tested for their antimicrobial activity against four prominent bacteria; Escherichia coli, Staphylococcus aureus, Enterococcus faecium and Klebsiella pneumoniae. AgGO was the most effective antimicrobial (Minimum inhibitory concentration E. coli/Enterococcus faecium 0.125 mg mL−1; S. aureus/K. pneumoniae 0.25 mg mL−1). The addition of Ag enhanced the activity of GO against the bacteria tested, including the generally recalcitrant K. pneumoniae and Enterococcus faecium. These findings demonstrated that GO-metal hybrids have the potential to be utilised as novel antimicrobials or biocides in liquid formulations, biomaterials or coatings for use in the treatment of wounds where medically relevant bacteria are becoming increasingly resistant
Cover Picture: Next‐Generation Additive Manufacturing: Tailorable Graphene/Polylactic(acid) Filaments Allow the Fabrication of 3D Printable Porous Anodes for Utilisation within Lithium‐Ion Batteries (Batteries & Supercaps 5/2019)
The prognostic value of location and size change of pathological lymph nodes evaluated on CT-scan following radiotherapy in head and neck cancer
Short- and long-term cause-specific survival of patients with inflammatory breast cancer
BACKGROUND: Inflammatory breast cancer (IBC) had been perceived to have a poor prognosis. Oncologists were not enthusiastic in the past to give aggressive treatment. Single institution studies tend to have small patient numbers and limited years of follow-up. Most studies do not report 10-, 15- or 20-year results. METHODS: Data was obtained from the population-based database of the Surveillance, Epidemiology, and End Results program of the National Cancer Institute from 1975–1995 using SEER*Stat5.0 software. This period of 21 years was divided into 7 periods of 3 years each. The years were chosen so that there was adequate follow-up information to 2000. ICD-O-2 histology 8530/3 was used to define IBC. The lognormal model was used for statistical analysis. RESULTS: A total of 1684 patients were analyzed, of which 84% were white, 11% were African Americans, and 5% belonged to other races. Age distribution was < 30 years in 1%, 30–40 in 11%, 40–50 in 22%, 50–60 in 24%, 60–70 in 21%, and > 70 in 21%. The lognormal model was validated for 1975–77 and for 1978–80, since the 10-, 15- and 20-year cause-specific survival (CSS) rates, could be calculated using the Kaplan-Meier method with data available in 2000. The data were then used to estimate the 10-, 15- and 20-year CSS rates for the more recent years, and to study the trend of improvement in survival. There were increasing incidences of IBC: 134 patients in the 1975–77 period to 416 patients in the 1993–95 period. The corresponding 20-year CSS increased from 9% to 20% respectively with standard errors of less than 4%. CONCLUSION: The improvement of survival during the study period may be due to introduction of more aggressive treatments. However, there seem to be no further increase of long-term CSS, which should encourage oncologists to find even more effective treatments. Because of small numbers of patients, randomized studies will be difficult to conduct. The SEER population-based database will yield the best possible estimate of the trend in improvement of survival for patients with IBC
A double-blind, placebo-controlled study of the short term effects of a spring water supplemented with magnesium bicarbonate on acid/base balance, bone metabolism and cardiovascular risk factors in postmenopausal women
<p>Abstract</p> <p>Background</p> <p>A number of health benefits including improvements in acid/base balance, bone metabolism, and cardiovascular risk factors have been attributed to the intake of magnesium rich alkaline mineral water. This study was designed to investigate the effects of the regular consumption of magnesium bicarbonate supplemented spring water on pH, biochemical parameters of bone metabolism, lipid profile and blood pressure in postmenopausal women.</p> <p>Findings</p> <p>In this double-blind, placebo-controlled, parallel-group, study, 67 postmenopausal women were randomised to receive between 1500 mL and 1800 mL daily of magnesium bicarbonate supplemented spring water (650 mg/L bicarbonate, 120 mg/L magnesium, pH 8.3-8.5) (supplemented water group) or spring water without supplements (control water group) over 84 days. Over this period biomarkers of bone turnover (serum parathyroid hormone (PTH), 1,25-dihydroxyvitamin D, osteocalcin, urinary telopeptides and hydroxyproline), serum lipids (total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides), venous and urinary pH were measured together with measurements of standard biochemistry, haematology and urine examinations.</p> <p>Serum magnesium concentrations and urinary pH in subjects consuming the magnesium bicarbonate supplemented water increased significantly at Day 84 compared to subjects consuming the spring water control (magnesium - p = 0.03; pH - p = 0.018). The consumption of spring water led to a trend for an increase in parathyroid hormone (PTH) concentrations while the PTH concentrations remained stable with the intake of the supplemented spring water. However there were no significant effects of magnesium bicarbonate supplementation in changes to biomarkers of bone mineral metabolism (n-telopeptides, hydroxyproline, osteocalcin and 1,25-dihydroxyvitamin D) or serum lipids or blood pressure in postmenopausal women from Day 0 to Day 84.</p> <p>Conclusions</p> <p>Short term regular ingestion of magnesium bicarbonate supplemented water provides a source of orally available magnesium. Long term clinical studies are required to investigate any health benefits.</p> <p>Trial registration</p> <p>ACTRN12609000863235</p
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