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1.
Sci Data ; 11(1): 326, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553544

RESUMEN

A 42-year climate data record of global sea surface temperature (SST) covering 1980 to 2021 has been produced from satellite observations, with a high degree of independence from in situ measurements. Observations from twenty infrared and two microwave radiometers are used, and are adjusted for their differing times of day of measurement to avoid aliasing and ensure observational stability. A total of 1.5 × 1013 locations are processed, yielding 1.4 × 1012 SST observations deemed to be suitable for climate applications. The corresponding observation density varies from less than 1 km-2 yr-1 in 1980 to over 100 km-2 yr-1 after 2007. Data are provided at their native resolution, averaged on a global 0.05° latitude-longitude grid (single-sensor with gaps), and as a daily, merged, gap-free, SST analysis at 0.05°. The data include the satellite-based SSTs, the corresponding time-and-depth standardised estimates, their standard uncertainty and quality flags. Accuracy, spatial coverage and length of record are all improved relative to a previous version, and the timeseries is routinely extended in time using consistent methods.

2.
Artículo en Inglés | MEDLINE | ID: mdl-36981591

RESUMEN

The Peruvian environmental action plan seeks headwaters protection as one of its integrated watershed management objectives. However, heterogeneous social and environmental conditions shape this freshwater management challenge at subnational scales. We have noticed different interpretations of this challenge. To map the debate, understand the diverse interpretations, and frame political choices, we conducted semi-structured interviews with institutional and non-institutional stakeholders for performing discourse analysis in an Andean watershed where mountaintop gold mining, midstream farmers, and the downstream Cajamarca city coexist. One discourse dominates the debate on protecting the freshwater supply and argues the importance of river impoundment, municipal storage capacity, and institutional leadership. The other two discourses revolve around protecting the mountain aquifer. The second discourse does so with a fatalistic view of headwaters protection and rural support. The third discourse partially shifts the debate towards the need for improving rural capacity building and (ground)water inventories. To understand evolutions in society, it is crucial to understand these three discourses, including the types of knowledge that actors present as legitimate, the attributed roles to all stakeholders, and the kinds of worldviews informing each discourse. The interaction among discourses could hinder integrated watershed management at worst or, at best, help inspire multi-stakeholder collaboration.


Asunto(s)
Ríos , Perú
3.
Environ Dev Sustain ; : 1-26, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36105251

RESUMEN

The wicked sustainability problems that we are increasingly facing not only require new ways of knowledge production, but also challenge our traditional educational system. More and more importance is attached to educational practices and experiments focusing on transdisciplinary problem framing, a pluralistic search for solutions and active collaboration with various stakeholders throughout society. The aim of this article is to investigate how an inter- and transdisciplinary setting in which students develop master theses can contribute to learning about a specific urban problem and what challenges this transdisciplinary education entails. Starting from relevant theoretical and analytical frameworks, such as Mode 2 Science (Nowotny et al. 2005) and the three-phase model of Lang et al. (2012), we first outline the philosophy and approach of the general setting: the Stadsacademie, a collective learning platform or 'collaboratory' to explore and investigate wicked problems perceived in the city of Ghent (Belgium). To provide more in-depth and refined insights, we focus on an exemplary activity of the Stadsacademie: the Master Thesis Ateliers 'Diversity in Social Housing'. A Master Thesis Atelier (MTA) is a collaborative trajectory of one academic year in which 4 to 8 master students and their supervisors from different disciplinary backgrounds concentrate on one specific urban problem and collaborate with non-academic actors aiming to explore and to impact upon that issue. We conclude this article with overall reflections and suggestions for transdisciplinary approaches within educational practices to tackle wicked sustainability issues.

4.
Indian J Radiol Imaging ; 31(3): 721-724, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34790323

RESUMEN

Gollop-Wolfgang complex is defined as the presence of a distal bifid femur and tibial hemimelia with or without hand ectrodactyly. The condition commonly presents with several skeletal abnormalities and internal organ congenital defects. We hereby report a case with a classical presentation of Gollop-Wolfgang complex.

5.
medRxiv ; 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32839780

RESUMEN

BACKGROUND: COVID-19 has stretched the ability of many institutions to supply needed personal protective equipment, especially N95 respirators. N95 decontamination and reuse programs provide one potential solution to this problem. Unfortunately, a comprehensive evaluation of the effects of decontamination on the integrity of various N95 models using a quantitative fit test (QTFT) approach is lacking. AIMS: 1) To investigate the effects of up to eight rounds of vaporized H2O2 (VHP) decontamination on the integrity of N95 respirators currently in use in a hospital setting. 2) To examine if N95 respirators worn by one user can adapt to the face shape of a second user with no compromise of integrity following VHP decontamination. METHODS: The PortaCount Pro+ Respirator Fit Tester Model 8038 was used to quantitatively define the integrity, measured by fit, of N95 respirators following decontamination with VHP. FINDINGS: There was an observable downward trend in the integrity of Halyard Fluidshield 46727 N95 respirators throughout eight cycles of decontamination with VHP. The integrity of 3M 1870 N95 respirators was significantly reduced after the respirator was worn, decontaminated with VHP, and then quantitatively fit tested on a second user. Furthermore, we uncovered inconsistencies between qualitative fit test and QTFT results that may have strong implications on the fit testing method used by institutions. CONCLUSIONS: Our data revealed variability in the integrity of different N95 models after VHP decontamination and exposed potential limitations of N95 decontamination and reuse programs.

6.
medRxiv ; 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32839785

RESUMEN

BACKGROUND: The COVID-19 pandemic has caused a severe shortage of personal protective equipment (PPE), especially N95 respirators. Efficient, effective and economically feasible methods for large-scale PPE decontamination are urgently needed. AIMS: (1) to develop protocols for effectively decontaminating PPE using vaporized hydrogen peroxide (VHP); (2) to develop novel approaches that decrease set up and take down time while also increasing decontamination capacity (3) to test decontamination efficiency for N95 respirators heavily contaminated by makeup or moisturizers. METHODS: We converted a decommissioned Biosafety Level 3 laboratory into a facility that could be used to decontaminate N95 respirators. N95 respirators were hung on metal racks, stacked in piles, placed in paper bags or covered with makeup or moisturizer. A VHP VICTORYTM unit from STERIS was used to inject VHP into the facility. Biological and chemical indicators were used to validate the decontamination process. FINDINGS: N95 respirators individually hung on metal racks were successfully decontaminated using VHP. N95 respirators were also successfully decontaminated when placed in closed paper bags or if stacked in piles of up to six. Stacking reduced the time needed to arrange N95 respirators for decontamination by approximately two-thirds while almost tripling facility capacity. Makeup and moisturizer creams did not interfere with the decontamination process. CONCLUSIONS: Respirator stacking can reduce the hands-on time and increase decontamination capacity. When personalization is needed, respirators can be decontaminated in labeled paper bags. Make up or moisturizers do not appear to interfere with VHP decontamination.

7.
Sci Data ; 6(1): 223, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31641133

RESUMEN

A climate data record of global sea surface temperature (SST) spanning 1981-2016 has been developed from 4 × 1012 satellite measurements of thermal infra-red radiance. The spatial area represented by pixel SST estimates is between 1 km2 and 45 km2. The mean density of good-quality observations is 13 km-2 yr-1. SST uncertainty is evaluated per datum, the median uncertainty for pixel SSTs being 0.18 K. Multi-annual observational stability relative to drifting buoy measurements is within 0.003 K yr-1 of zero with high confidence, despite maximal independence from in situ SSTs over the latter two decades of the record. Data are provided at native resolution, gridded at 0.05° latitude-longitude resolution (individual sensors), and aggregated and gap-filled on a daily 0.05° grid. Skin SSTs, depth-adjusted SSTs de-aliased with respect to the diurnal cycle, and SST anomalies are provided. Target applications of the dataset include: climate and ocean model evaluation; quantification of marine change and variability (including marine heatwaves); climate and ocean-atmosphere processes; and specific applications in ocean ecology, oceanography and geophysics.

8.
JAMA ; 321(17): 1686-1692, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-31063574

RESUMEN

Importance: Fecal immunochemical tests for hemoglobin are widely used for colorectal cancer (CRC) screening. Observational studies suggested that sensitivity of fecal immunochemical tests for detecting advanced neoplasms could be increased by acetylsalicylic acid (aspirin), especially among men. Objective: To evaluate the potential to increase sensitivity of fecal immunochemical tests by administering a single 300-mg oral aspirin dose 2 days before stool sampling. Design, Setting, and Participants: A randomized, placebo-controlled, double-blind trial was conducted in 14 gastroenterology practices and 4 hospitals in Germany, and included 2422 men and women aged 40 to 80 years scheduled for colonoscopy, with no recent use of aspirin or other drugs with antithrombotic effects (enrollment from June 2013 to November 2016, and final follow-up January 27, 2017). Interventions: Administration of a single tablet containing 300 mg of aspirin (n = 1208) or placebo (n = 1214) 2 days before fecal sampling for fecal immunochemical test. Main Outcome and Measures: The primary outcome was sensitivity of a quantitative fecal immunochemical test at 2 predefined cutoffs (10.2 and 17-µg Hb/g stool) for detecting advanced neoplasms (colorectal cancer or advanced adenoma). Results: Among 2422 randomized patients (mean [SD] age, 59.6 [7.9] years; 1219, 50%, men), 2134 were included in the analysis (78% for primary screening colonoscopy, 22% for diagnostic colonoscopy). Advanced neoplasms were identified in 224 participants (10.5%), including 8 participants (0.4%) with CRC and 216 participants (10.1%) with advanced adenoma. Sensitivity was 40.2% in the aspirin group and 30.4% in the placebo group (difference 9.8%, 95% CI, -3.1% to 22.2%, P = .14) at cutoff 10.2-µg Hb/g stool and 28.6% in the aspirin and 22.5% in the placebo group (difference 6.0%, 95% CI, -5.7% to 17.5%, P = .32) at cutoff 17-µg Hb/g stool. Conclusions and Relevance: Among adults aged 40 to 80 years not using aspirin or other antithrombotic medications, administration of a single dose of oral aspirin prior to fecal immunochemical testing, compared with placebo, did not significantly increase test sensitivity for detecting advanced colorectal neoplasms at 2 predefined cutoffs of a quantitative fecal immunochemical test. Trial registration: Deutsches Register Klinischer Studien Identifier: DRKS00003252; EudraCT Identifier: 2011-005603-32/DE.


Asunto(s)
Aspirina/administración & dosificación , Neoplasias Colorrectales/diagnóstico , Sangre Oculta , Adenoma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
9.
Appl Physiol Nutr Metab ; 34(1): 1-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19234579

RESUMEN

An increased dietary intake of n-3 highly unsaturated fatty acids (HUFA; >or=20 carbons, >or=3 carbon-carbon double bonds), particularly eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), is associated with the decreased risk and incidence of several morbidities afflicting the elderly, including cognitive decline, dementia, rheumatoid arthritis, and macular degeneration. In this study, the dietary intake and blood levels of fatty acids were directly determined in residents of a retirement home or assisted living phase of a continuum of care facility for Canadian seniors. Finger-tip-prick blood samples, 3-day food duplicates, and 3-day food records were collected. The fatty acid composition of food duplicates and blood was determined by gas chromatography. Fifteen participants (7 male, 8 female; 87.1 +/- 4.8 years of age) completed the protocol. The daily intake of EPA and DHA combined, determined directly, was 70 mg (95% CI, 41-119) or 0.036% of total energy (95% CI, 0.022-0.058). In finger-tip-prick blood, the percent of n-3 HUFA in total HUFA of whole blood, a biomarker of n-3 polyunsaturated fatty acid status, was 28.8 +/- 5.2%. Correlations between daily n-3 HUFA intake and n-3 HUFA in blood were not significant (r = 0.14; n = 15), but became significant after the removal of 2 participants who appeared to consume fish irregularly (r = 0.59; n = 13). The n-3 HUFA intake and corresponding n-3 HUFA blood levels of Canadian long-term care residents are lower than levels estimated to prevent several morbidities associated with aging.


Asunto(s)
Instituciones de Vida Asistida , Dieta , Ácidos Docosahexaenoicos/administración & dosificación , Ácido Eicosapentaenoico/administración & dosificación , Servicios de Salud para Ancianos , Hogares para Ancianos , Estado Nutricional , Anciano de 80 o más Años , Envejecimiento , Biomarcadores/sangre , Canadá , Cromatografía de Gases , Registros de Dieta , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Femenino , Humanos , Cuidados a Largo Plazo , Masculino , Encuestas Nutricionales
10.
Acta Oncol ; 47(4): 654-61, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18465333

RESUMEN

This paper describes the procedure of changing from 2D to 3D treatment planning guidelines for post-mastectomy radiotherapy in Denmark. The aim of introducing 3D planning for post-mastectomy radiotherapy was to optimize the target coverage and minimize the dose to the normal tissues. Initially, it was investigated whether it was possible to find a treatment technique alternative to the one recommended by the Danish Breast Cancer Cooperative Group (DBCG). A dosimetric comparison of a combined photon/electron 3-field technique (3F) and a partial wide tangent technique (PWT) was carried out on individual planning CT-scans from seven patients selected to represent a wide range of sizes and shapes of chest walls. The heart dose was lower for PWT than for 3F, however, for both techniques the dose was within the accepted constraints. The lung dose was higher but acceptable for six of the seven patients with PWT. The dose to the internal mammary nodes (IMN) was not satisfactory for five of the seven patients for 3F, whereas only two of the seven patients had a minimum dose lower than 95% of the prescribed dose with PWT. Finally, the dose to the contralateral breast was increased when using PWT compared to 3F. It was concluded that PWT was an appropriate choice of technique for future radiation treatment of post-mastectomy patients. A working group was formed and guidelines for 3D planning were developed during a series of workshops where radiation oncologists and physicists from all radiotherapy centres participated. This work also included a definition of the tissue structures needed to be outlined on the planning CT-scan. The work was initiated in 2003 and the guidelines were approved by the DBCG Radiotherapy Committee in 2006. The first of January 2007 the 3D guidelines had been fully implemented in five of the seven radiotherapy centres.


Asunto(s)
Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Planificación de la Radioterapia Asistida por Computador/métodos , Mama/efectos de la radiación , Neoplasias de la Mama/patología , Terapia Combinada , Dinamarca , Femenino , Corazón/efectos de la radiación , Humanos , Pulmón/efectos de la radiación , Metástasis Linfática , Mastectomía Segmentaria , Guías de Práctica Clínica como Asunto , Dosificación Radioterapéutica
11.
Strahlenther Onkol ; 182(11): 666-71, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17072525

RESUMEN

PURPOSE: To evaluate 5-year prostate-specific antigen (PSA) relapse-free survival of transperineal permanent seed implantation (TPSI) in 118 patients with "low-risk" prostate cancer, that means stage cT1c-T2a, Gleason Score < 7, and initial PSA value < 10 ng/ml. PATIENTS AND METHODS: From 04/1999 to 06/2002, a total of 118 patients underwent a mono-TPSI, using ultrasound-based preplanning and intraoperative verification by both ultrasound and conventional fluoroscopy as well as postoperative CT planning. Patients were monitored during the 1st year in 3-month intervals, and in 6-monthly intervals from then onward. Biochemical failure was defined according to ASTRO criteria with three consecutive PSA rises observed from a posttreatment nadir PSA value. The median follow-up was 48.9 months (range: 37.0-80.2 months). 114 patients were eligible, four patients were lost to follow-up. RESULTS: For the entire group, PSA relapse-free survival at 5 years was 94.7%, with six patients (5.3%) having a PSA relapse between 8 and 20 months after implantation. In the bNED patients (no biochemical evidence of disease), PSA values were < 0.2 ng/ml in 82.5% (94/114 patients), < 0.5 ng/ml in 13.2% (15/114 patients), < 1.0 ng/ml in 2.6% (3/114 patients), and < 1.5 ng/ml in 1.7% (2/114 patients). In summary, PSA values < 0.2 ng/ml, < 0.5 ng/ml and < 1.0 ng/ml occurred in 82.5%, 95.7% and 98.3%, respectively. Out of the six patients with recurrent disease, three had a local tumor recurrence only, and three developed distant metastases. CONCLUSION: In low-risk prostate cancer patients, TPSI with intraoperative ultrasound-based treatment planning and fluoroscopy leads to excellent local tumor control and PSA relapse-free survival.


Asunto(s)
Adenocarcinoma/radioterapia , Braquiterapia/métodos , Radioisótopos de Yodo/administración & dosificación , Neoplasias de la Próstata/radioterapia , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Anciano , Biopsia , Braquiterapia/efectos adversos , Estudios de Cohortes , Supervivencia sin Enfermedad , Fluoroscopía , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Próstata/patología , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía
12.
Chemistry ; 10(2): 382-91, 2004 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-14735507

RESUMEN

The new quaternary niobium thiophosphates ANb(2)P(2)S(12) (A=K, Rb, Cs) have been prepared and characterized. The title compounds were synthesized by reacting Nb metal, A(2)S, P(2)S(5), and S at 600-700 degrees C in evacuated silica tubes. They crystallize as "stuffed" variants of the tetragonal TaPS(6) structure type in the tetragonal space group I$\bar 4$2d with eight formula units per unit cell and lattice constants a=15.923(2) and c=13.238(3) A for CsNb(2)P(2)S(12), a=15.887(3) and c=13.132(3) A for RbNb(2)P(2)S(12), and a=15.850(2) and c=13.119(3) A for KNb(2)P(2)S(12). Their structures are based on double helices formed from interpenetrating, noninteracting spiral chains of binuclear [Nb(2)S(12)] cluster units and [PS(4)] thiophosphate groups. The cavities and tunnels, which are formed by the helical chains, are filled with A(+) ions. Temperature-dependent conductivity studies reveal thermally activated electrical transport behavior. This result is consistent with the observation of a temperature-dependent contribution to the (31)P MAS-NMR shift, suggesting that the delocalized s-electron spin density increases with increasing temperature. These findings are supported by the results of tight-binding band structure calculations which reveal that the unusual electrical transport behavior of ANb(2)P(2)S(12) is a consequence of the structure symmetry. Therefore, CsNb(2)P(2)S(12) may be considered a chalcogenide analogue of metal phosphate bronzes.

13.
Strahlenther Onkol ; 179(6): 417-22, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12789469

RESUMEN

PURPOSE: To determine whether dose distribution achieved with treatment plans using high- and low-activity (125)I implants differs. PATIENTS AND METHODS: Based on intraoperative transrectal ultrasound scans of 71 patients, inverse automated treatment plans (IATP) were performed with 15.5-kBq (0.42-mCi) and 25.2-kBq (0.68-mCi) (125)I implants using a commercial 3-D planning system (Variseed). A prescription dose of 145 Gy in 98% of the prostate volume (V100), a maximum dose to the urethra of 250 Gy (D1), and a maximum dose to 10% of the anterior rectal wall of 145 Gy (D10) were required. The plans were manually corrected, if necessary. RESULTS: In the IATP, a better dose coverage of the prostate was found for high-activity seeds (V100 of 98% vs 84%). The prostate dose values increased with the prostate volume. After manual optimization, the differences were only marginal with a prostate V100 of 99% for both activities, a urethra D1 of 247 Gy and 239 Gy, and a rectum D10 of 135 Gy and 124 Gy for high- and low-activity seeds. Low-activity seeds required more sources (66 vs 47) and needles (24 vs 17; all numbers are median values). CONCLUSIONS: Concerning the prostate dose coverage, high-activity seeds are superior in the IATP. After manual adjustment, the dose values for the prostate and the organs at risk are similar. Considering a supposedly decreased toxicity and a shorter implantation time for a lower number of seeds, we recommend high-activity seeds for experienced teams.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Yodo/uso terapéutico , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Humanos , Masculino , Próstata/anatomía & histología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/cirugía , Dosificación Radioterapéutica , Análisis de Regresión , Ultrasonografía , Uretra/efectos de la radiación
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