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1.
Sci Total Environ ; 921: 171036, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38373449

RESUMEN

findings are presented from an investigation to improve understanding of the environmental risks associated with developing an unconventional-hydrocarbons industry in the UK. The EQUIPT4RISK project, funded by UK Research Councils, focused on investigations around Preston New Road (PNR), Fylde, Lancashire, and Kirby Misperton Site A (KMA), North Yorkshire, where operator licences to explore for shale gas by hydraulic fracturing (HF) were issued in 2016, although exploration only took place at PNR. EQUIPT4RISK considered atmospheric (greenhouse gases, air quality), water (groundwater quality) and solid-earth (seismicity) compartments to characterise and model local conditions and environmental responses to HF activities. Risk assessment was based on the source-pathway-receptor approach. Baseline monitoring of air around the two sites characterised the variability with meteorological conditions, and isotopic signatures were able to discriminate biogenic methane (cattle) from thermogenic (natural-gas) sources. Monitoring of a post-HF nitrogen-lift (well-cleaning) operation at PNR detected the release of atmospheric emissions of methane (4.2 ± 1.4 t CH4). Groundwater monitoring around KMA identified high baseline methane concentrations and detected ethane and propane at some locations. Dissolved methane was inferred from stable-isotopic evidence as overwhelmingly of biogenic origin. Groundwater-quality monitoring around PNR found no evidence of HF-induced impacts. Two approaches for modelling induced seismicity and associated seismic risk were developed using observations of seismicity and operational parameters from PNR in 2018 and 2019. Novel methodologies developed for monitoring include use of machine learning to identify fugitive atmospheric methane, Bayesian statistics to assess changes to groundwater quality, a seismicity forecasting model seeded by the HF-fluid injection rate and high-resolution monitoring of soil-gas methane. The project developed a risk-assessment framework, aligned with ISO 31000 risk-management principles, to assess the theoretical combined and cumulative environmental risks from operations over time. This demonstrated the spatial and temporal evolution of risk profiles: seismic and atmospheric impacts from the shale-gas operations are modelled to be localised and short-lived, while risk to groundwater quality is longer-term.

2.
PLoS One ; 10(12): e0145639, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26713621

RESUMEN

Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) has proven to be a powerful technique revealing complexity and diversity of natural DOM molecules, but its application to DOM analysis in grazing-impacted agricultural systems remains scarce. In the present study, we presented a case study of using ESI-FTICR-MS in analyzing DOM from four headwater streams draining forest- or pasture-dominated watersheds in Virginia, USA. In all samples, most formulas were CHO compounds (71.8-87.9%), with other molecular series (CHOS, CHON, CHONS, and CHOP (N, S)) accounting for only minor fractions. All samples were dominated by molecules falling in the lignin-like region (H/C = 0.7-1.5, O/C = 0.1-0.67), suggesting the predominance of allochthonous, terrestrial plant-derived DOM. Relative to the two pasture streams, DOM formulas in the two forest streams were more similar, based on Jaccard similarity coefficients and nonmetric multidimensional scaling calculated from Bray-Curtis distance. Formulas from the pasture streams were characterized by lower proportions of aromatic formulas and lower unsaturation, suggesting that the allochthonous versus autochthonous contributions of organic matter to streams were modified by pasture land use. The number of condensed aromatic structures (CAS) was higher for the forest streams, which is possibly due to the controlled burning in the forest-dominated watersheds and suggests that black carbon was mobilized from soils to streams. During 15-day biodegradation experiments, DOM from the two pasture streams was altered to a greater extent than DOM from the forest streams, with formulas with H/C and O/C ranges similar to protein (H/C = 1.5-2.2, O/C = 0.3-0.67), lipid (H/C = 1.5-2.0, O/C = 0-0.3), and unsaturated hydrocarbon (H/C = 0.7-1.5, O/C = 0-0.1) being the most bioreactive groups. Aromatic compound formulas including CAS were preferentially removed during combined light+bacterial incubations, supporting the contention that black carbon is labile to light alterations. Collectively, our data demonstrate that headwater DOM composition contains integrative information on watershed sources and processes, and the application of ESI-FTICR-MS technique offers additional insights into compound composition and reactivity unrevealed by fluorescence and stable carbon isotopic measurements.


Asunto(s)
Bosques , Análisis de Fourier , Compuestos Orgánicos/química , Ríos/química , Espectrometría de Masa por Ionización de Electrospray , Monitoreo del Ambiente , Luz
3.
J Fish Biol ; 86(5): 1457-70, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25809583

RESUMEN

This study developed and applied an approach to calculate the proportion of fish gut content composed of mucus secreted by the oropharyngeal cavity and gut. The amount of nitrogen in the contents of the foregut (oesophagus and gizzard) and the epibranchial organs of suspension-feeding American gizzard shad Dorosoma cepedianum was significantly higher than the nitrogen in the homogeneous food source. Using data collected from suspension-feeding experiments and the nitrogen content of D. cepedianum mucus, a series of equations illustrated that mucus constituted c. 10% of D. cepedianum foregut content and 12% of epibranchial organ content by dry mass. Future quantification of fish feeding selectivity and absorption efficiency can use this approach to take into account the contribution of fish mucus to the nutrients in the gut contents. This study supports the conclusion that suspension-feeding D. cepedianum in a heterogeneous environment selectively ingest nutrient-rich particles, even when gut nutrient content is adjusted to take into account the contribution of mucus.


Asunto(s)
Alimentación Animal , Peces , Moco/química , Nitrógeno/química , Animales , Esófago/metabolismo , Conducta Alimentaria , Molleja No Aviar/metabolismo
4.
Prehosp Emerg Care ; 4(3): 205-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10895913

RESUMEN

INTRODUCTION: Pain and its control have been studied extensively in the emergency department. Numerous studies indicate that inadequate treatment of pain is common, despite the availability of myriad analgesics. It has been suggested that oligoanesthesia is also a common practice in the prehospital setting. OBJECTIVE: To assess the use of prehospital analgesia in patients with suspected extremity fracture. METHODS: Emergency medical services (EMS) call reports were reviewed for all patients with suspected extremity fractures treated from June 1997 to July 1998 in a midwestern community with a population base of 223,000. Data collected included demographic information, mechanism of injury, medications given, and field treatment. Standing orders for administration of analgesia were available and permitted paramedics to give either morphine sulfate or nitrous oxide per protocol. RESULTS: The EMS call reports were analyzed for 1,073 patients with suspected extremity fractures. The mean patient age was 47 years. Accidental injuries comprised 86.5% of those reviewed. Suspected leg fractures were most common (20%), followed by hips (18%), arms (11%), knees (10%), ankles (9%), shoulders (7.2%), hands (5.5%), and wrists (5.3%). Multiple trauma and assorted broken digits accounted for the remaining 14%. The most common mechanisms of injury were: fall (43%), motor vehicle collision (21%), and human assault (10%). Intravenous lines were placed in 9.4% of patients; 17% received ice packs; 16% received bandage/dressings; 25% received air splints; and 19% were fully immobilized. Analgesia was administered to 18 patients (1.8%): 16 patients received nitrous oxide and two received morphine. CONCLUSION: Administration of analgesics to prehospital patients with suspected fractures was rare. Prehospital identification and treatment of pain for patients with musculoskeletal trauma could be improved.


Asunto(s)
Analgésicos/uso terapéutico , Servicios Médicos de Urgencia/métodos , Extremidades/lesiones , Fracturas Óseas/tratamiento farmacológico , Dolor/tratamiento farmacológico , Evaluación de Procesos, Atención de Salud , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Fracturas Óseas/complicaciones , Fracturas Óseas/epidemiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Morfina/uso terapéutico , Óxido Nitroso/uso terapéutico , Ohio/epidemiología , Dolor/etiología , Estudios Retrospectivos
5.
J Endourol ; 13(10): 745-50, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10646682

RESUMEN

BACKGROUND: Urologists continue to search for alternatives to transurethral prostatectomy that carry a lower potential for complications. PATIENTS AND METHODS: Twenty-five patients on the public waiting list for transurethral resection of the prostate, all spontaneously voiding, underwent transurethral needle ablation of the prostate (TUNA). Eight patients had a simultaneous bladder neck incision (BNI). Follow-up with International Prostate Symptom Scores and flow rate measurement was performed at 6 weeks, 7 months, and 1 year. RESULTS: A statistically significant increase in flow rate and fall in symptom scores occurred out to 1 year after TUNA. Despite this result, six patients (24%) were not satisfied with their outcome and underwent a second endoscopic operation. CONCLUSION: In our hands, TUNA produced an unsatisfactory clinical result.


Asunto(s)
Ablación por Catéter , Procedimientos Quirúrgicos Mínimamente Invasivos , Próstata/cirugía , Anciano , Animales , Ablación por Catéter/instrumentación , Estudios de Seguimiento , Humanos , Masculino , Agujas , Periodo Posoperatorio , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/cirugía , Calidad de Vida , Reoperación , Resultado del Tratamiento , Obstrucción del Cuello de la Vejiga Urinaria/etiología , Obstrucción del Cuello de la Vejiga Urinaria/fisiopatología , Micción
6.
Pathology ; 28(1): 105-6, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8714285

RESUMEN

We present the case of a 45-yr-old female patient with a 23 yr history of interstitial cystitis that multiple surgical procedures, including a ceco-cystoplasty, were unable to cure. After a cystectomy was performed, histological examination of the bladder showed the development of collagenous colitis. Although the etiology of both interstitial cystitis and collagenous colitis is unknown, this report postulates an association between these two conditions.


Asunto(s)
Colitis/etiología , Colitis/patología , Colágeno , Cistitis Intersticial/patología , Colectomía/efectos adversos , Cistectomía/efectos adversos , Cistitis Intersticial/cirugía , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias
7.
Fam Pract ; 10(4): 416-23, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8168678

RESUMEN

The objectives of this study were (i) to investigate whether there were any differences between how doctors behave when ill and how they would recommend other doctors to behave; (ii) to determine whether doctors think self-investigation and self-medication are acceptable; and (iii) to find out if doctors working in general practice and hospitals agree about how other doctors should manage their own ill health. A questionnaire enquiring about expected or recommended behaviour for 10 medical conditions and acceptability of self-investigation by 10 procedures and self-medication with 10 drug groups was sent to 59 general practitioners (GPs) and 65 hospital consultants in the same geographical area. Response rates were 78.7 and 81.3% from GPs and hospital specialists respectively. A wide range of responses was given for each question. General practitioners were significantly more likely to recommend other doctors if sick to consult their own GP, but significantly more likely to expect to treat themselves. Hospital specialists were significantly more likely to advise sick doctors to consult specialists directly rather than their GPs. There was little consensus about whether self-investigation and self-medication was acceptable.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Médicos de Familia , Autocuidado , Adulto , Femenino , Humanos , Masculino , Cuerpo Médico de Hospitales , Medicina , Automedicación , Especialización , Encuestas y Cuestionarios
10.
Br J Urol ; 49(6): 545-51, 1977 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-588963

RESUMEN

A post-mortem study of the urethral anatomy following gonorrhoea is presented. The different specimens examined demonstrated lesions ranging from microscopic submucosal scars to fully developed urethral strictures. In every specimen extensive squamous metaplasia of the surface epithelium was present. It is postulated that overstretching of this unsupported squamous epithelium during voiding causes microscopic epithelial tears and that the accumulation of the subsequent microscopic scars leads to the formation of a urethral stricture. Bacterial infection does not seem to play any part in the genesis of the stricture.


Asunto(s)
Estrechez Uretral/patología , Adulto , Anciano , Niño , Epitelio/patología , Gonorrea/complicaciones , Gonorrea/patología , Humanos , Masculino , Persona de Mediana Edad , Úlcera/patología , Uretra/anatomía & histología , Uretra/patología , Estrechez Uretral/etiología , Uretritis/patología
15.
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