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2.
Sci Total Environ ; 636: 1362-1372, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29913597

RESUMEN

The Ganga-Brahmaputra-Meghna (GBM) River System, the associated Hooghly River and the Mahanadi River System represent the largest river basins in the world serving a population of over 780 million. The rivers are of vital concern to India and Bangladesh as they provide fresh water for people, agriculture, industry, conservation and support the Delta System in the Bay of Bengal. Future changes in both climate and socio-economics have been investigated to assess whether these will alter river flows and water quality. Climate datasets downscaled from three different Global Climate Models have been used to drive a daily process based flow and water quality model. The results suggest that due to climate change the flows will increase in the monsoon period and also be enhanced in the dry season. However, once socio-economic changes are also considered, increased population, irrigation, water use and industrial development reduce water availability in drought conditions, threatening water supplies and posing a threat to river and coastal ecosystems. This study, as part of the DECCMA (Deltas, vulnerability and Climate Change: Migration and Adaptation) project, also addresses water quality issues, particularly nutrients (N and P) and their transport along the rivers and discharge into the Delta System. Climate will alter flows, increasing flood flows and changing pollution dilution factors in the rivers, as well as other key processes controlling water quality. Socio-economic change will affect water quality, as water diversion strategies, increased population and industrial development alter the water balance and enhance fluxes of nutrients from agriculture, urban centers and atmospheric deposition.

3.
Sci Total Environ ; 637-638: 1069-1080, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29801202

RESUMEN

As the scientific consensus concerning global climate change has increased in recent decades, research on potential impacts of climate change on water resources has been given high importance. However in Sub-Saharan Africa, few studies have fully evaluated the potential implications of climate change to their water resource systems. The Volta River is one of the major rivers in Africa covering six riparian countries (mainly Ghana and Burkina Faso). It is a principal water source for approximately 24 million people in the region. The catchment is primarily agricultural providing food supplies to rural areas, demonstrating the classic water, food, energy nexus. In this study an Integrated Catchment Model (INCA) was applied to the whole Volta River system to simulate flow in the rivers and at the outlet of the artificial Lake Volta. High-resolution climate scenarios downscaled from three different Global Climate Models (CNRM-CM5, HadGEM2-ES and CanESM2), have been used to drive the INCA model and to assess changes in flow by 2050s and 2090s under the high climate forcing scenario RCP8.5. Results show that peak flows during the monsoon months could increase into the future. The duration of high flow could become longer compared to the recent condition. In addition, we considered three different socio-economic scenarios. As an example, under the combined impact from climate change from downscaling CNRM-CM5 and medium+ (high economic growth) socio-economic changes, the extreme high flows (Q5) of the Black Volta River are projected to increase 11% and 36% at 2050s and 2090s, respectively. Lake Volta outflow would increase +1% and +5% at 2050s and 2090s, respectively, under the same scenario. The effects of changing socio-economic conditions on flow are minor compared to the climate change impact. These results will provide valuable information assisting future water resource development and adaptive strategies in the Volta Basin.

4.
Br J Cancer ; 112(7): 1183-9, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25756395

RESUMEN

BACKGROUND: The effect of chemotherapy on health-related quality of life (HRQoL) in malignant pleural mesothelioma (MPM) is poorly understood. Patient-individualised prognostication and prediction of treatment response from chemotherapy is useful but little evidence exists to guide practice. METHOD: Consecutive patients with MPM who were fit for first-line chemotherapy with pemetrexed and cisplatin\carboplatin were recruited and followed up for a minimum of 12 months. This study focussed on the HRQoL outcomes of these patients using the EQ-5D, EORTC QLQ-C30 and LC13. RESULTS: Seventy-three patients were recruited of which 58 received chemotherapy and 15 opted for best supportive care (BSC). Compliance with HRQoL questionnaires was 98% at baseline. The chemotherapy group maintained HRQoL compared with the BSC group whose overall HRQoL fell (P=0.006) with worsening dyspnoea and pain. The impact of chemotherapy was irrespective of histological subtype although those with non-epithelioid disease had worse HRQoL at later time points (P=0.012). Additionally, those with a falling mesothelin or improvement on modified-RECIST CT at early follow-up had a better HRQoL at 16 weeks. CONCLUSIONS: HRQoL was maintained following chemotherapy compared with a self-selected BSC group. Once chemotherapy is initiated, a falling mesothelin or improved RECIST CT findings infer a quality-of-life advantage.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Mesotelioma/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Carboplatino/administración & dosificación , Cisplatino/administración & dosificación , Femenino , Glutamatos/administración & dosificación , Guanina/administración & dosificación , Guanina/análogos & derivados , Humanos , Neoplasias Pulmonares/patología , Masculino , Mesotelioma/patología , Mesotelioma Maligno , Persona de Mediana Edad , Cuidados Paliativos , Pemetrexed , Estudios Prospectivos , Calidad de Vida
5.
Br J Cancer ; 112(7): 1175-82, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25756396

RESUMEN

BACKGROUND: Robust markers that predict prognosis and detect early treatment response in malignant pleural mesothelioma (MPM) would enhance patient care. METHODS: Consecutive patients with MPM who were considered fit for first-line chemotherapy were prospectively recruited. Patients of similar performance status opting for best supportive care were included as a comparator group. Baseline and interval CT, PET-CT and serum markers (mesothelin, fibulin-3 and neutrophil-lymphocyte ratio (NLR)) were obtained, and patients followed up for a minimum 12 months. FINDINGS: Seventy-three patients were recruited (58 chemotherapy/15 comparator arm). Baseline TGV (total glycolytic volume on PET-CT) was an independent predictor of worse overall survival (OS) (P=0.001). Change in interval TGV(baseline/after two cycles of chemotherapy) did not predict OS or chemotherapy response on CT. Baseline NLR<4 was an independent predictor of better OS (median survival 453 (IQR 272-576) days vs NLR⩾4, 257 (IQR 147-490), P=0.002). Although baseline serum mesothelin did not predict OS, a falling level at 8 weeks significantly predicted longer time to progression (TTP) (P<0.001). INTERPRETATION: Neutrophil-lymphocyte ratio and baseline TGV predict prognosis in malignant pleural mesothelioma (MPM), but PET-CT is unhelpful in monitoring chemotherapy response. Serum mesothelin is a useful early treatment response marker when measured serially during chemotherapy and may have a role in evaluating patients' treatment response.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/sangre , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/tratamiento farmacológico , Mesotelioma/sangre , Mesotelioma/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Carboplatino/administración & dosificación , Cisplatino/administración & dosificación , Estudios de Cohortes , Femenino , Glutamatos/administración & dosificación , Guanina/administración & dosificación , Guanina/análogos & derivados , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Linfocitos/patología , Masculino , Mesotelioma/diagnóstico por imagen , Mesotelioma Maligno , Imagen Multimodal , Neutrófilos/patología , Pemetrexed , Tomografía de Emisión de Positrones , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
6.
J Chem Phys ; 123(8): 084702, 2005 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-16164316

RESUMEN

Anti-Stokes/Stokes asymmetries under surface enhanced Raman scattering (SERS) conditions are studied for a wide variety of SERS-active media and different analytes. Evidence is provided for the existence of underlying resonances that create these asymmetries. We show here that these resonances are associated with the electromagnetic coupling between the analyte (probe) and the metal. The work demonstrates the use of the anti-Stokes/Stokes ratio as a tool to understand the hierarchy of resonances in the SERS problem, which is essential for quantification purposes.

7.
Psychosomatics ; 42(1): 35-40, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11161119

RESUMEN

The authors examined the presence of posttraumatic stress symptoms (PTSS) in 20 patients requiring ventilation after acute respiratory distress. The subjects completed a semistructured interview about their ventilation experience that was subject to content and linguistic analysis. Subjects also completed two self-report measures to assess PTSS and socioemotional adjustment. Subjects who endorsed PTSS were more likely to use a narrative style suggesting emotional involvement in their recall of the stressful event. The authors indicate that the presence of PTSS is a common consequence of traumatic medical experiences and that denial of distress may be an adaptive short-term coping strategy.


Asunto(s)
Respiración Artificial/efectos adversos , Respiración Artificial/psicología , Síndrome de Dificultad Respiratoria/terapia , Trastornos por Estrés Postraumático/etiología , Trastornos por Estrés Postraumático/psicología , Adaptación Psicológica , Humanos , Entrevistas como Asunto , Lingüística , Factores de Riesgo , Estadísticas no Paramétricas , Encuestas y Cuestionarios
8.
Appl Opt ; 40(1): 136-44, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18356984

RESUMEN

The classical Wolter type I grazing-incidence x-ray telescope consists of a paraboloidal primary mirror and a confocal hyperboloidal secondary mirror. This design exhibits stigmatic imaging on-axis but suffers from coma, astigmatism, field curvature, and higher-order aberrations such as oblique spherical aberration. Wolter-Schwarzschild designs have been developed that strictly satisfy the Abbe sine condition and thus exhibit no spherical aberration or coma. However, for wide-field applications such as the solar x-ray imager (SXI), there is little merit in a design with stigmatic imaging on-axis. Instead, one needs to optimize some area-weighted-average measure of resolution over the desired operational field of view. This has traditionally been accomplished by mere despacing of the focal plane of the classical Wolter type I telescope. Here we present and evaluate in detail a family of hyperboloid-hyperboloid grazing-incidence x-ray telescope designs whose wide-field performance is much improved over that of an optimally despaced Wolter type I and even somewhat improved over that of an optimally despaced Wolter-Schwarzschild design.

9.
J Org Chem ; 65(14): 4241-50, 2000 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-10891122

RESUMEN

The readily prepared gem-dibromocyclopropanes (+/-)-13 and (+/-)-19 each engage in a silver(I)-promoted electrocyclic ring-opening/pi-allyl cation cyclization sequence to deliver the hexahydroindole (+/-)-20, which participates in a Suzuki cross-coupling reaction with arylboronic acid 3 to give the tetracyclic compound (+/-)-21. Catalytic hydrogenation of this last compound proceeds in a completely stereoselective manner to give the saturated analogue (+/-)-24, which undergoes Bischler-Napieralski cyclization on reaction with phosphorus oxychloride. The resulting lactam (+/-)-25 is then reduced with lithium aluminum hydride to give (+/-)-gamma-lycorane [(+/-)-1]. By using (-)-menthyl-derived carbamates 27 and 28, this chemistry has been extended to the synthesis of the (+)- and (-)-modifications of the title compound.


Asunto(s)
Alcaloides/síntesis química , Alcaloides de Amaryllidaceae , Ciclopropanos/síntesis química , Disacáridos/síntesis química , Inhibidores Enzimáticos/síntesis química , Fucosiltransferasas/antagonistas & inhibidores , Glicósido Hidrolasas/antagonistas & inhibidores , Animales , Conformación de Carbohidratos , Disacáridos/química , Disacáridos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Cinética , Modelos Moleculares , Conformación Molecular
11.
J Antimicrob Chemother ; 45(2): 247-50, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10660511

RESUMEN

Meropenem administered as a single iv 3 g dose once every 24 h was used to treat nine ambulatory patients with infective exacerbations of bronchiectasis. Serum meropenem concentrations were measured before dosing and at 30 min after each 30 min infusion. Mean pre-dose concentrations were <0.1 mg/L and mean post-dose concentrations 93.9 +/- 29.5 mg/L (95% confidence interval (CI) 86. 2-101.6, n = 59). A pathogen was cultured from sputum in six patients and eradicated (<100 cfu/g sputum) in all but one by day 6 of therapy. Previous work on animals has shown that a bacteriostatic effect is seen with meropenem when t > MIC is greater than 20-30% of the dose interval. In these nine patients, this could be achieved and was associated with successful outcome for pathogens for which MICs are

Asunto(s)
Bronquiectasia/complicaciones , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/etiología , Tienamicinas/uso terapéutico , Anciano , Bronquiectasia/microbiología , Femenino , Infecciones por Haemophilus/tratamiento farmacológico , Infecciones por Haemophilus/microbiología , Haemophilus influenzae , Semivida , Humanos , Masculino , Meropenem , Persona de Mediana Edad , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/microbiología , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Infecciones del Sistema Respiratorio/microbiología
13.
Appl Opt ; 38(31): 6469-81, 1999 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18324177

RESUMEN

Most authors include a paraxial (small-angle) limitation in their discussion of diffracted wave fields. This paraxial limitation severely limits the conditions under which diffraction behavior is adequately described. A linear systems approach to modeling nonparaxial scalar diffraction theory is developed by normalization of the spatial variables by the wavelength of light and by recognition that the reciprocal variables in Fourier transform space are the direction cosines of the propagation vectors of the resulting angular spectrum of plane waves. It is then shown that wide-angle scalar diffraction phenomena are shift invariant with respect to changes in the incident angle only in direction cosine space. Furthermore, it is the diffracted radiance (not the intensity or the irradiance) that is shift invariant in direction cosine space. This realization greatly extends the range of parameters over which simple Fourier techniques can be used to make accurate calculations concerning wide-angle diffraction phenomena. Diffraction-grating behavior and surface-scattering effects are two diffraction phenomena that are not limited to the paraxial region and benefit greatly from this new development.

14.
Parasitology ; 117 ( Pt 3): 229-34, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9774787

RESUMEN

A new and simple colorimetric method has been developed for determining activity in vitro against Giardia intestinalis. The microtitre plate assay is based upon the nucleoside hydrolase activity released from G. intestinalis by lysis. Action of the nucleoside hydrolase on the substrate analogue, 4-nitrophenyl beta-D-ribofuranoside (NPR), gives rise to a coloured product which may be determined directly by the change in absorbance. A number of other such nucleoside analogues can be similarly used, but NPR is the preferred substrate, since it gives high enzymic activity at a relatively low substrate concentration. The IC50 values determined using this method for the known anti-giardials metronidazole, tinidazole and furazolidone were consistent with previously published values. The method is simple, does not involve radioisotopes or complex instrumentation, and thus provides a convenient method for screening potential anti-giardial agents.


Asunto(s)
Compuestos Cromogénicos/química , Colorimetría/métodos , Giardia lamblia/crecimiento & desarrollo , Giardiasis/tratamiento farmacológico , Nucleotidasas/química , Animales , Antitricomonas/farmacología , Antitricomonas/uso terapéutico , Furazolidona/farmacología , Furazolidona/uso terapéutico , Giardia lamblia/efectos de los fármacos , Giardia lamblia/enzimología , Concentración 50 Inhibidora , Metronidazol/farmacología , Metronidazol/uso terapéutico , Ribonucleósidos/química , Sensibilidad y Especificidad , Tinidazol/farmacología , Tinidazol/uso terapéutico
15.
Appl Opt ; 37(21): 4782-8, 1998 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-18285936

RESUMEN

The detection and processing of laser communication signals are affected by the fading induced onto these signals by atmospheric turbulence. One method of reducing this fading is to use an array of detectors in which each of the detector outputs are added together coherently. We present experimental verification and theory of a 1.06 mum eight-element coherent receiver used to mitigate the effects of fading over a 1-km outdoor range. The carrier-to-noise ratio (CNR) was measured on a single channel and was then compared with the CNR obtained from the coherent sum of the eight channels. The increase of the mean CNR for the coherent sum as compared with a single aperture was observed proportional to the number of the apertures under different conditions of atmospheric turbulence. The measured mean CNR gain fitted the theoretical prediction well when the laser intensity fluctuations followed the gamma distribution.

16.
Thorax ; 52(10): 927-9; discussion 926-7, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9404384

RESUMEN

Three cases of pneumonia due to Neisseria meningitidis are described. In all three cases the organism was isolated only from blood cultures, but in the presence of good clinical and radiological evidence of pneumonia. The isolates belonged to three different serogroups: B type 2b, C, and Y. The cases illustrate the fact that N meningitidis can cause pneumonia and that culture of blood plays an important part in the diagnosis. Clinically there is nothing to differentiate meningococcal pneumonia from other causes of community acquired pneumonia. Predisposing factors include aspiration, immunosuppression, influenza, and adenovirus infections. When diagnosed, pneumonia due to N meningitidis should be notified and prophylaxis given as for meningitis or septicaemia.


Asunto(s)
Infecciones Meningocócicas/complicaciones , Neisseria meningitidis , Neumonía Bacteriana/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Infecciones Meningocócicas/diagnóstico , Persona de Mediana Edad , Neisseria meningitidis/clasificación , Neumonía Bacteriana/diagnóstico
18.
Laryngoscope ; 106(5 Pt 1): 589-94, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8628086

RESUMEN

Ninety-five patients with laryngeal and hypopharyngeal cancer were examined and staged preoperatively by clinical evaluation (CE) and computed tomography (CT). The CE and CT staging were compared to each other and to the pathologic (PT) staging of the tumors. The CT staging showed high accuracy in staging transglottic (88%), supraglottic (68%), and oropharyngeal tumors invading the larynx (68%) when compared to the PT findings. The CT staging was less effective in evaluating glottic tumors (46%), both overstaging (12%) and understaging (20%) cases. Combined CE-CT evaluation showed higher accuracy in staging all tumors (84%) compared to CE alone (52%) or CT alone (68%). The findings suggest that combined CE-CT should be used to evaluate laryngeal and hypopharyngeal tumors.


Asunto(s)
Neoplasias Hipofaríngeas/diagnóstico , Neoplasias Laríngeas/diagnóstico , Estadificación de Neoplasias/métodos , Tomografía Computarizada por Rayos X , Errores Diagnósticos , Humanos , Neoplasias Hipofaríngeas/diagnóstico por imagen , Neoplasias Hipofaríngeas/patología , Neoplasias Laríngeas/diagnóstico por imagen , Neoplasias Laríngeas/patología , Estudios Prospectivos
19.
Appl Opt ; 35(21): 4220-8, 1996 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-21102831

RESUMEN

The active illumination of a target through a turbulent medium with a monostatic transmitter-receiver results in a naturally occurring conjugate wave caused by reciprocal scattering paths that experience identical phase variations. This reciprocal path-scattering phenomenon produces an enhanced backscatter in the retroverse direction (precisely along the boresight of the pointing telescope). A dual aperture causes this intensity enhancement to take the form of Young's interference fringes. Interference fringes produced by the reciprocal path-scattering phenomenon are temporally stable even in the presence of time-varying turbulence. Choosing the width-to-separation ratio of the dual apertures appropriately and utilizing orthogonal polarizations to suppress the time-varying common-path scattered radiation allow one to achieve interferometric sensitivity in pointing accuracy through a random medium or turbulent atmosphere. Computer simulations are compared with laboratory experimental data. This new precision pointing and tracking technique has potential applications in ground-to-space laser communications, laser power beaming to satellites, and theater missile defense scenarios.

20.
Thorax ; 50(4): 426-7, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7785021

RESUMEN

A bronchus arising directly from the trachea is an infrequent congenital anomaly which usually represents the displaced origin of a normal bronchus. Rarely, a true supernumerary tracheal bronchus occurs supplying an associated tracheal lobe. The case is described of a patient in whom a supernumerary tracheal bronchus and tracheal lobe was demonstrated by computed tomographic scanning and magnetic resonance imaging.


Asunto(s)
Bronquios/anomalías , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Tráquea/anomalías , Femenino , Humanos , Persona de Mediana Edad
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