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1.
J Environ Manage ; 324: 116245, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36352725

RESUMEN

Fire directly impacts soil properties responsible for soil function and can result in soil degradation. Across the globe, climate change-induced droughts and elevated temperatures are exacerbating fire regime severity, breadth, and frequency, thus posing a threat to soil function and dependent ecosystem services. In Australia, the 2019-2020 fire season consumed nearly 50% of Kangaroo Island, South Australia, burning both dry sclerophyll woodland and adjacent historically cleared and grazed pastureland. Due to exacerbated fire regime elements, e.g., intensity and area affected, and interactions with historical land use, post-fire recovery of soil function was uncertain. This study assessed the impacts of a) the 2019-2020 fire event in Western River, Kangaroo Island on dry sclerophyll woodland and b) the interaction between this fire event and historical clearing and grazing on post-fire function of the soil. To do so, the following physicochemical and biological soil properties were analysed: labile active carbon, total carbon, total nitrogen, carbon to nitrogen ratio (C/N), pH, electrical conductivity, soil water repellency, aggregate stability, microbial community composition, and microbial diversity. Our results showed that the fire was of high severity, causing a reduction in nutrient content, an extreme rise in pH, and significant modifications to fungal communities in burnt compared to unburnt dry sclerophyll woodland. Furthermore, clearing and grazing raised post-fire soil nutrient levels and soil microbial diversity but reduced soil C/N and the abundance of ectomycorrhizal fungi in burnt pastureland compared to burnt woodland soils. This study highlights the role of management and fire severity in post-fire outcomes and emphasizes the need for comprehensive soil function assessments to evaluate the impacts of disturbance on soil. Taking direct measure of soil properties, as done here, will improve future assessments of fire season impacts and post-fire recovery in fire-prone landscapes.


Asunto(s)
Incendios , Microbiota , Suelo/química , Ecosistema , Bosques , Nitrógeno/análisis , Carbono
2.
Eur J Cancer ; 172: 237-251, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35797761

RESUMEN

BACKGROUND: The impact of body mass index (BMI) on long-term survival outcomes after colorectal cancer surgery is debated. DESIGN: A systematic literature review and meta-analysis was performed to compare long-term survival outcomes of patients of different BMI categories after colorectal cancer surgery. RESULTS: Of the 2588 articles screened, 56 articles met the inclusion criteria, reporting on 72,582 participants. Patients with BMI <18.5 had significantly worse overall survival [hazard ratio (HR) 1.91; P < 0.0001], cancer-specific survival (HR = 1.91; P < 0.0001), disease-free survival (HR = 1.50; P < 0.0001) and recurrence-free survival (HR = 1.13; P = 0.007) compared to patients with a BMI of 18.5-25. There was no significant difference between those with BMI 25-30 and 18.5-25 in overall survival, cancer-specific survival, disease-free survival and recurrence-free survival, except for the subgroup of patients with colon cancer where patients with BMI 25-30 had significantly improved overall survival (HR = 0.90; P = 0.05) and disease-free survival (HR = 0.90; P = 0.04). Patients with BMI >30 had significantly worse disease-free survival (HR = 1.05; P = 0.03) compared to patients with a BMI of 18.5-25, but no significant difference in overall survival, cancer-specific survival and recurrence-free survival. Patients with BMI >35 compared to 18.5-25 had significantly worse overall survival (HR = 1.24; P = 0.02), cancer-specific survival (HR = 1.36; P = 0.01), disease-free survival (HR = 1.15; P = 0.03) and recurrence-free survival for colon (HR = 1.11; P = 0.04) and rectal (HR = 4.10; P = 0.04) cancer. CONCLUSIONS: Being underweight (BMI < 18.5) or class II/III obese (BMI > 35) at the time of colorectal cancer surgery may result in worse long-term survival outcomes, whereas being overweight (BMI 25-30) may improve survival in a subgroup of patients with colon cancer. Optimising BMI may preoperatively improve long-term survival after surgery for colorectal cancer.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Índice de Masa Corporal , Neoplasias Colorrectales/cirugía , Humanos , Obesidad/complicaciones , Sobrepeso , Factores de Riesgo
3.
Environ Sci Process Impacts ; 23(8): 1116-1129, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34190221

RESUMEN

There is a need for the development of effective baselines against which the water quality impacts of new developments can be assessed. The specific conductance of flowback water from shale gas operations is typically many times the specific conductance of surface water and near-surface groundwater. This contrast in specific conductance means that specific conductance could be the ideal determinand for detecting water quality impacts from shale gas extraction. If specific conductance is to be used for detecting the impacts of shale gas operations, then a baseline of specific conductance in water bodies is required. Here, Bayesian hierarchical modelling of specific conductance was applied across English groundwater. The modelling used existing, spot-sampled data from the years 2000 to 2018 from 537 unique borehole locations. When the differences between boreholes was considered, then the approach was sufficiently sensitive to detect 1% mixing of fracking fluid in groundwater at a 95% confidence interval. The Bayesian hierarchical modelling maximises the return on public investment and provides a means by which future observations can be judged.


Asunto(s)
Agua Subterránea , Fracking Hidráulico , Contaminantes Químicos del Agua , Teorema de Bayes , Gas Natural , Yacimiento de Petróleo y Gas , Contaminantes Químicos del Agua/análisis , Calidad del Agua
4.
Am J Sports Med ; 49(5): 1348-1354, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33729858

RESUMEN

BACKGROUND: Sports-related concussion is a worldwide problem. There is a concern that an initial concussion can cause prolonged subclinical disturbances to sensorimotor function that increase the risk of subsequent injury. The primary aim of this study was to examine whether a history of sports-related concussion has effects on static and dynamic balance performance in adolescent rugby players. HYPOTHESIS: Dynamic balance would be worse in players with a history of concussion compared with those with no history of concussion. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Male adolescent rugby players aged 14 to 18 years from 5 schools were recruited before the start of the 2018-2019 playing season. Participants completed questionnaires and physical tests, including dynamic Y balance and single-leg static balance (eyes closed) tests, while performing single and dual tasks. Dynamic balance was assessed using inertial sensor instrumentation. Dependent variables were normalized reach distance and the sample entropy (SEn) of the 3 axes (x, y, and z). RESULTS: Of the 195 participants, 100 reported a history of concussion. Those with a history of concussion demonstrated higher SEn in all directions, with highest values during anterior (standardized mean difference [SMD], 0.4; 95% CI, 0.0-0.7; P = .027) and posteromedial (SMD, 0.5; 95% CI, 0.2-0.9; P = .004) reach directions compared with those with no history. There was no difference between groups (concussion history vs control) in traditional Y balance reach distances in the anterior or posteromedial directions or single-leg static balance during both single- (P = .47) and dual-task (P = .67) conditions. CONCLUSION: Adolescent rugby union athletes with a history of concussion had poorer dynamic balance during performance tasks compared with healthy controls. Static single-leg balance tests, either single or dual task, may not be sensitive enough to detect sensorimotor deficits in those with a history of concussion.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Fútbol Americano , Adolescente , Atletas , Estudios Transversales , Humanos , Masculino , Equilibrio Postural , Instituciones Académicas
6.
J Surg Case Rep ; 2020(3): rjaa045, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32201559

RESUMEN

Primary retroperitoneal mucinous cystadenoma (PRMC) is a rare tumour. It was first reported in 1965, and since then, less than 100 cases have been reported. It is cystic in nature and most commonly affects the female population. It becomes symptomatic in later stages due to its mass effect, making the diagnosis challenging in its early asymptomatic stage. We report a case of a 32-year-old female who presented with abdominal pain and a mass in left iliac fossa. Diagnostic imaging revealed a large cystic lesion in retroperitoneum. A midline laparotomy was performed, and a complete surgical excision was accomplished without any spillage. Surgical histology confirmed the diagnosis of PRMC. The patient was discharged on postoperative day 2. There was no evidence of tumour recurrence on repeat imaging at 90-day follow-up. Surgical approach, with complete resection and without any spillage, remains the most effective and appropriate treatment for this tumour.

7.
J Surg Case Rep ; 2020(3): rjaa004, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32161635

RESUMEN

Epidermoid inclusion cysts of the perineal region are a rare entity, which require appropriate diagnosis and management. Here we describe the unusual case of a large protruding epidermoid inclusion cyst originating from the intersphincteric anal plane, which was mobilized and excised successfully. Essential investigations to ensure accurate diagnosis in addition to surgical technique to reduce recurrence and patient morbidity are described in this case report.

8.
Sci Total Environ ; 631-632: 1638-1648, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29555117

RESUMEN

Natural gas pipelines are an important source of fugitive methane emissions in lifecycle greenhouse gas assessments but limited monitoring has taken place of UK pipelines to quantify fugitive emissions. This study investigated methane emissions from the UK high-pressure pipeline system (National Transmission System - NTS) for natural gas pipelines. Mobile surveys of CH4 emissions were conducted across four areas in the UK, with routes bisecting high-pressure pipelines (with a maximum operating pressure of 85bar) and separate control routes away from the pipelines. A manual survey of soil gas measurements was also conducted along one of the high-pressure pipelines using a tunable diode laser. For the pipeline routes, there were 26 peaks above 2.1ppmv CH4 at 0.23peaks/km, compared with 12 peaks at 0.11peaks/km on control routes. Three distinct thermogenic emissions were identified on the basis of the isotopic signal from these elevated concentrations with a peak rate of 0.03peaks/km. A further three thermogenic emissions on pipeline routes were associated with pipeline infrastructure. Methane fluxes from control routes were statistically significantly lower than the fluxes measured on pipeline routes, with an overall pipeline flux of 627 (241-1123 interquartile range) tonnes CH4/km/yr. Soil gas CH4 measurements indicated a total flux of 62.6ktCH4/yr, which equates to 2.9% of total annual CH4 emissions in the UK. We recommend further monitoring of the UK natural gas pipeline network, with assessments of transmission and distribution stations, and distribution pipelines necessary.

9.
Environ Int ; 89-90: 248-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26922565

RESUMEN

Hydraulic fracturing (fracking) has been used extensively in the US and Canada since the 1950s and offers the potential for significant new sources of oil and gas supply. Numerous other countries around the world (including the UK, Germany, China, South Africa, Australia and Argentina) are now giving serious consideration to sanctioning the technique to provide additional security over the future supply of domestic energy. However, relatively high population densities in many countries and the potential negative environmental impacts that may be associated with fracking operations has stimulated controversy and significant public debate regarding if and where fracking should be permitted. Road traffic generated by fracking operations is one possible source of environmental impact whose significance has, until now, been largely neglected in the available literature. This paper therefore presents a scoping-level environmental assessment for individual and groups of fracking sites using a newly-created Traffic Impacts Model (TIM). The model produces estimates of the traffic-related impacts of fracking on greenhouse gas emissions, local air quality emissions, noise and road pavement wear, using a range of hypothetical fracking scenarios to quantify changes in impacts against baseline levels. Results suggest that the local impacts of a single well pad may be short duration but large magnitude. That is, whilst single digit percentile increases in emissions of CO2, NOx and PM are estimated for the period from start of construction to pad completion (potentially several months or years), excess emissions of NOx on individual days of peak activity can reach 30% over baseline. Likewise, excess noise emissions appear negligible (<1dBA) when normalised over the completion period, but may be considerable (+3.4dBA) in particular hours, especially in night-time periods. Larger, regional scale modelling of pad development scenarios over a multi-decade time horizon give modest CO2 emissions that vary between 2.5 and 160.4kT, dependent on the number of wells, and individual well fracking water and flowback waste requirements. The TIM model is designed to be adaptable to any geographic area where the required input data are available (such as fleet characteristics, road type and quality), and we suggest could be deployed as a tool to help reach more informed decisions regarding where and how fracking might take place taking into account the likely scale of traffic-related environmental impacts.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Fracking Hidráulico , Modelos Teóricos , Ruido , Emisiones de Vehículos/análisis , Reino Unido
10.
Aging Ment Health ; 16(5): 584-91, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22360649

RESUMEN

OBJECTIVE: To evaluate a newly developed integrated digital prosthetic, the COGKNOW Day Navigator (CDN), to support persons with mild dementia in their daily lives, with memory, social contacts, daily activities and safety. METHODS: A user participatory method was applied in the development process, which consisted of three iterative 1-year cycles with field tests in Amsterdam, Belfast and Luleå. In the successive cycles 16, 14 and 12 persons with dementia and their carers participated. Data on usability were collected by means of interviews, observations, questionnaires, logging and diaries. The CDN prototype consists of a touch screen, a mobile device, sensors and actuators. RESULTS: The evaluation showed that persons with dementia and carers valued the CDN overall as user-friendly and useful. Conclusions regarding the effectiveness of the system in daily life were limited due to insufficient duration of the testing period caused by delays in development and some instability of the final prototype. CONCLUSION: With the suggested adaptations, the CDN is expected to be a useful tool for supporting community-dwelling persons with mild dementia and their carers.


Asunto(s)
Actividades Cotidianas , Demencia/rehabilitación , Relaciones Interpersonales , Anciano , Anciano de 80 o más Años , Cuidadores , Electrónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dispositivos de Autoayuda
12.
Nano Lett ; 10(4): 1472-6, 2010 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-20232812

RESUMEN

This work demonstrates the use of wetting nanoporous alumina template with polymer solution to produce arrays of isolated poly(vinylidene fluoride) (PVDF) ferroelectric gamma-type nanorods supported within a nonpolar alpha-structure film. The method is based upon a crystal phase transition which occurs due to PVDF confinement within alumina nanoporous. The system was studied using scanning X-ray microdiffraction (micro-XRD) that allows the solid-solid phase transition from the alpha-nonpolar crystal form (bulk) to the gamma polar ferroelectric form (nanorod array) to be spatially resolved, as well as providing crystallinity and orientation information. The results reveal that the interaction between polymer chains and the porous membrane's walls imposes a flat-on lamella growth along the nanorrods long axis, while improving crystal orientation.


Asunto(s)
Membranas Artificiales , Nanotecnología/métodos , Nanotubos/química , Polivinilos/química , Óxido de Aluminio/química , Electricidad , Nanotecnología/instrumentación , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
13.
Can J Surg ; 52(4): E123-E126, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19680501
14.
J Synchrotron Radiat ; 16(Pt 1): 22-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19096170

RESUMEN

This article describes the current status of the microRaman set-up at the ID13 beamline of the European Synchrotron Radiation Facility. This offers an in situ on-axis microprobe which has a common focal position to the X-ray microbeam and can collect spectral data simultaneously. It can also be used in an offline sample characterization role, both before and after beamline experiments. To demonstrate the application of microRaman spectroscopy within a beamline environment, a number of examples are given.

15.
J Am Chem Soc ; 130(50): 17070-4, 2008 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-19053481

RESUMEN

We have characterized the steps involved in silk assembly from the protein solution into beta-type fibers by a combination of small-angle and wide-angle X-ray scattering and Raman spectroscopy. The aggregation process was studied in a concentric flow microfluidic cell, which allows mimicking the spinning duct. The fibroin molecule in solution shows an elongated shape with a maximum diameter of 38 nm. During the pH-driven initial assembly step, large-scale aggregates of fibroin molecules with a maximum diameter of about 260 nm are formed. Raman spectroscopy on the dried, fibrous material shows a principally alpha-helical silk I secondary structure, which is transformed gradually into beta-type silk II by increasing immersion times in water. The formation of crystalline beta-sheet domains within the fiber is confirmed by wide-angle X-ray scattering. The assembly process resembles the peptide condensation-ordering model proposed for amyloid cross-beta formation.


Asunto(s)
Seda/química , Sincrotrones , Animales , Bombyx/química , Modelos Moleculares , Análisis Espectral
16.
Adv Exp Med Biol ; 617: 297-304, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18497052

RESUMEN

Breast epithelia maintain an ionic and electrical gradient across the ductal lumen, which can be measured using ductal epithelial impedance spectroscopy (DEIS). Furthermore, the breast remodels itself through a secretory, proliferative, and involutional cycle each month in premenopausal women, which changes the electrical properties of the epithelium. DEIS was used to examine the electrical properties of breast epithelia in 14 normal women at multiple points during 1-2 menstrual cycles with IRB/patient consent. The epithelial resistance (Re) measured 159 +/- 26 kOmega (mean +/- SEM) in week 1 (n = 55) of menstrual cycle, when the epithelium is single layered and atrophic, increased to 217 +/- 20 kOmega (p < 0.05) by weeks 2-3 (n = 129), as the epithelium becomes more proliferative and multilayered, and reached 263 +/- 30 kOmega (p = 0.002) by week 4 (n = 75). The capacitance of the epithelium increased between week 2 and 3 of the cycle from 0.32 +/- 0.02 microF (microFarads) to 0.51 +/- 0.05 microF (p = 0.003), when the epithelial cell mass is greatest. The characteristic frequency (fC) of the epithelium, a property related to morphology and transport function, decreases progressively through weeks 1-4 of menstrual cycle from 17 +/- 3 to 11 +/- 2, 10 +/- 1, and finally to 7 +/- 1 Hz respectively (p = 0.003). This study demonstrates that the electrical properties of breast epithelium are dependent on the time during the menstrual cycle, and likely represents morphological changes in breast epithelia associated with the menstrual cycle. Patients at risk for breast cancer may have an aberrant epithelial response to estrogen and progesterone. Electrical measurements of the epithelium using DEIS, during the menstrual cycle, may represent a novel biomarker for assessing BC risk.


Asunto(s)
Neoplasias de la Mama/fisiopatología , Mama/fisiología , Conductividad Eléctrica , Impedancia Eléctrica , Ciclo Menstrual/fisiología , Adulto , Biomarcadores , Epitelio , Femenino , Humanos
17.
Artículo en Inglés | MEDLINE | ID: mdl-19162773

RESUMEN

Persons suffering from mild dementia can benefit from a form of cognitive prosthetic which can be used to assist them with their day to day activities. Within our current work we are aiming to develop a successful user-validated cognitive prosthetic for persons with mild dementia. We have devised a three phased waterfall methodology to support our developments. Based on the evaluation of the first of these phases which involved the processes of user requirements gathering, prototype development and evaluation of in situ deployment of the technology we have been able to guide the technical development within the second phase of our work. Within this paper we provide an overview of the first phase of our methodology and demonstrate how we have used the results from this to guide the second phase of our work, especially with regards to the notion of personalisation.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/rehabilitación , Sistemas de Administración de Bases de Datos , Bases de Datos Factuales , Demencia/rehabilitación , Sistemas Recordatorios , Interfaz Usuario-Computador , Trastornos del Conocimiento/etiología , Demencia/complicaciones , Humanos , Prótesis e Implantes
18.
Artículo en Inglés | MEDLINE | ID: mdl-19163414

RESUMEN

In this paper we present a multimedia tool that allows personalisation and configuration of an assistive technology. We have developed a tool called HomePUI that allows configuration of three disease domains; cognitive, physical and chronic. In this paper we present the rationale for our work, details of the developed tool and also present two case studies in which the tool has been used within cognitive and chronic disease management domains.


Asunto(s)
Dispositivos de Autoayuda , Enfermedad Crónica , Cognición , Sistemas de Computación , Computadores , Demencia/terapia , Diseño de Equipo , Servicios de Atención de Salud a Domicilio , Humanos , Manejo del Dolor , Lenguajes de Programación , Reproducibilidad de los Resultados , Programas Informáticos , Factores de Tiempo , Interfaz Usuario-Computador
19.
Artículo en Inglés | MEDLINE | ID: mdl-18002573

RESUMEN

The demands of introducing a more practical means of managing and monitoring technology within the home environment to support independent living are increasing. Within this paper we present a prototype solution, referred to as HomeCI, which allows healthcare professionals to establish the conditions/rules within which technology in the home should operate. The HomeCI concept is based on the use of visual notation and has been designed for use by healthcare professionals with a non technical background. Within the paper we present the design of the first version of the HomeCI visual editor and present the results of a usability study conducted on 4 healthcare professionals.


Asunto(s)
Servicios de Atención de Salud a Domicilio/organización & administración , Programas Informáticos , Servicios de Salud para Ancianos/organización & administración , Internet
20.
Small ; 3(8): 1438-44, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17583889

RESUMEN

A high-yielding synthesis afforded a hexa-peri-hexabenzocoronene carrying acrylate units at the end of six attached alkyl spacers. The polymerization of these acrylate moieties could be initiated with thermal energy and through direct photoactivation without the addition of a photoinitiator. This allowed the organization of the liquid-crystalline material to be fixed in either the crystalline state or the mesophase, which preserved the organization in the respective phase. The use of a focused synchrotron beam permitted selected regions of a thin film to be rendered insoluble. After "developing" the film in this lithographic process by dissolving the soluble, unpolymerized material, defined nano-objects remained on the substrate. In addition, the pronounced aromatic pi stacking of the novel material allows an organization in mesoporous membranes that could be fixed by thermal crosslinking. After the removal of the inorganic template, mechanically stable nanotubes were obtained, which were characterized by different microscopy techniques.


Asunto(s)
Acrilatos/química , Cristalización/métodos , Cristales Líquidos/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Titanio/química , Reactivos de Enlaces Cruzados/química , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
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