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1.
Nat Commun ; 15(1): 6911, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160176

RESUMEN

Urbanization and climate change are contributing to severe flooding globally, damaging infrastructure, disrupting economies, and undermining human well-being. Approaches to make cities more resilient to floods are emerging, notably with the design of flood-resilient structures, but relatively little is known about the role of urban form and its complexity in the concentration of flooding. We leverage statistical mechanics to reduce the complexity of urban flooding and develop a mean-flow theory that relates flood hazards to urban form characterized by the ground slope, urban porosity, and the Mermin order parameter which measures symmetry in building arrangements. The mean-flow theory presents a dimensionless flood depth that scales linearly with the urban porosity and the order parameter, with different scaling for disordered square- and hexagon-like forms. A universal scaling is obtained by introducing an effective mean chord length representative of the unobstructed downslope travel distance for flood water, yielding an analytical model for neighborhood-scale flood hazards globally. The proposed mean-flow theory is applied to probe city-to-city variations in flood hazards, and shows promising results linking recorded flood losses to urban form and observed rainfall extremes.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38852710

RESUMEN

BACKGROUND: Utilization in outpatient total shoulder arthroplasties (TSAs) has increased significantly in recent years. It remains largely unknown whether utilization of outpatient TSA differs across gender and racial groups. This study aimed to quantify racial and gender disparities both nationally and by geographic regions. METHODS: 168,504 TSAs were identified using Medicare fee-for-service (FFS) inpatient and outpatient claims data and beneficiary enrollment data from 2020 to 2022Q4. The percentage of outpatient cases, defined as cases discharged on the same day of surgery, was evaluated by racial and gender groups and by different census divisions. A multivariate logistics regression model controlling for patient socio-demographic information (white vs. non-white race, age, gender, and dual eligibility for both Medicare and Medicaid), hierarchical condition category (HCC) score, hospital characteristics, year fixed effects, and patient residency state fixed effects was performed. RESULTS: The TSA volume per 1000 beneficiaries was 2.3 for the White population compared to 0.8, 0.6 and 0.3 for the Black, Hispanic, and Asian population, respectively. A higher percentage of outpatient TSAs were in White patients (25.6%) compared to Black patients (20.4%) (p < 0.001). The Black TSA patients were also younger, more likely to be female, more likely to be dually eligible for Medicaid, and had higher HCC risk scores. After controlling for patient socio-demographic characteristics and hospital characteristics, the odds of receiving outpatient TSAs were 30% less for Black than the White group (OR 0.70). Variations were observed across different census divisions with South Atlantic (0.67, p < 0.01), East North Central (0.56, p < 0.001), and Middle Atlantic (0.36, p < 0.01) being the four regions observed with significant racial disparities. Statistically significant gender disparities were also found nationally and across regions, with an overall odds ratio of 0.75 (p < 0.001). DISCUSSION: Statistically significant racial and gender disparities were found nationally in outpatient TSAs, with Black patients having 30% (p < 0.001) fewer odds of receiving outpatient TSAs than white patients, and female patients with 25% (p < 0.001) fewer odds than male patients. Racial and gender disparities continue to be an issue for shoulder arthroplasties after the adoption of outpatient TSAs.

3.
J Clim Chang Health ; 15: 100292, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38425789

RESUMEN

Introduction: Climate change is a global phenomenon with far-reaching consequences, and its impact on human health is a growing concern. The intricate interplay of various factors makes it challenging to accurately predict and understand the implications of climate change on human well-being. Conventional methodologies have limitations in comprehensively addressing the complexity and nonlinearity inherent in the relationships between climate change and health outcomes. Objectives: The primary objective of this paper is to develop a robust theoretical framework that can effectively analyze and interpret the intricate web of variables influencing the human health impacts of climate change. By doing so, we aim to overcome the limitations of conventional approaches and provide a more nuanced understanding of the complex relationships involved. Furthermore, we seek to explore practical applications of this theoretical framework to enhance our ability to predict, mitigate, and adapt to the diverse health challenges posed by a changing climate. Methods: Addressing the challenges outlined in the objectives, this study introduces the Complex Adaptive Systems (CAS) framework, acknowledging its significance in capturing the nuanced dynamics of health effects linked to climate change. The research utilizes a blend of field observations, expert interviews, key informant interviews, and an extensive literature review to shape the development of the CAS framework. Results and discussion: The proposed CAS framework categorizes findings into six key sub-systems: ecological services, extreme weather, infectious diseases, food security, disaster risk management, and clinical public health. The study employs agent-based modeling, using causal loop diagrams (CLDs) tailored for each CAS sub-system. A set of identified variables is incorporated into predictive modeling to enhance the understanding of health outcomes within the CAS framework. Through a combination of theoretical development and practical application, this paper aspires to contribute valuable insights to the interdisciplinary field of climate change and health. Integrating agent-based modeling and CLDs enhances the predictive capabilities required for effective health outcome analysis in the context of climate change. Conclusion: This paper serves as a valuable resource for policymakers, researchers, and public health professionals by employing a CAS framework to understand and assess the complex network of health impacts associated with climate change. It offers insights into effective strategies for safeguarding human health amidst current and future climate challenges.

4.
Adv Water Resour ; 1762023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37601703

RESUMEN

Land surface depressions play a central role in the transformation of rainfall to ponding, infiltration and runoff, yet digital elevation models (DEMs) used by spatially distributed hydrologic models that resolve land surface processes rarely capture land surface depressions at spatial scales relevant to this transformation. Methods to generate DEMs through processing of remote sensing data, such as optical and light detection and ranging (LiDAR) have favored surfaces without depressions to avoid adverse slopes that are problematic for many hydrologic routing methods. Here we present a new topographic conditioning workflow, Depression-Preserved DEM Processing (D2P) algorithm, which is designed to preserve physically meaningful surface depressions for depression-integrated and efficient hydrologic modeling. D2P includes several features: (1) an adaptive screening interval for delineation of depressions, (2) the ability to filter out anthropogenic land surface features (e.g., bridges), (3) the ability to blend river smoothing (e.g., a general downslope profile) and depression resolving functionality. From a case study in the Goodwin Creek Experimental Watershed, D2P successfully resolved 86% of the ponds at a DEM resolution of 10 m. Topographic conditioning was achieved with minimum impact as D2P reduced the number of modified cells from the original DEM by 51% compared to a conventional algorithm. Furthermore, hydrologic simulation using a D2P processed DEM resulted in a more robust characterization on surface water dynamics based on higher surface water storage as well as an attenuated and delayed peak streamflow.

5.
Eur Radiol ; 33(11): 8067-8076, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37328641

RESUMEN

OBJECTIVES: Surgical planning of vestibular schwannoma surgery would benefit greatly from a robust method of delineating the facial-vestibulocochlear nerve complex with respect to the tumour. This study aimed to optimise a multi-shell readout-segmented diffusion-weighted imaging (rs-DWI) protocol and develop a novel post-processing pipeline to delineate the facial-vestibulocochlear complex within the skull base region, evaluating its accuracy intraoperatively using neuronavigation and tracked electrophysiological recordings. METHODS: In a prospective study of five healthy volunteers and five patients who underwent vestibular schwannoma surgery, rs-DWI was performed and colour tissue maps (CTM) and probabilistic tractography of the cranial nerves were generated. In patients, the average symmetric surface distance (ASSD) and 95% Hausdorff distance (HD-95) were calculated with reference to the neuroradiologist-approved facial nerve segmentation. The accuracy of patient results was assessed intraoperatively using neuronavigation and tracked electrophysiological recordings. RESULTS: Using CTM alone, the facial-vestibulocochlear complex of healthy volunteer subjects was visualised on 9/10 sides. CTM were generated in all 5 patients with vestibular schwannoma enabling the facial nerve to be accurately identified preoperatively. The mean ASSD between the annotators' two segmentations was 1.11 mm (SD 0.40) and the mean HD-95 was 4.62 mm (SD 1.78). The median distance from the nerve segmentation to a positive stimulation point was 1.21 mm (IQR 0.81-3.27 mm) and 2.03 mm (IQR 0.99-3.84 mm) for the two annotators, respectively. CONCLUSIONS: rs-DWI may be used to acquire dMRI data of the cranial nerves within the posterior fossa. CLINICAL RELEVANCE STATEMENT: Readout-segmented diffusion-weighted imaging and colour tissue mapping provide 1-2 mm spatially accurate imaging of the facial-vestibulocochlear nerve complex, enabling accurate preoperative localisation of the facial nerve. This study evaluated the technique in 5 healthy volunteers and 5 patients with vestibular schwannoma. KEY POINTS: • Readout-segmented diffusion-weighted imaging (rs-DWI) with colour tissue mapping (CTM) visualised the facial-vestibulocochlear nerve complex on 9/10 sides in 5 healthy volunteer subjects. • Using rs-DWI and CTM, the facial nerve was visualised in all 5 patients with vestibular schwannoma and within 1.21-2.03 mm of the nerve's true intraoperative location. • Reproducible results were obtained on different scanners.


Asunto(s)
Neuroma Acústico , Humanos , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/cirugía , Neuroma Acústico/patología , Estudios Prospectivos , Imagen de Difusión Tensora/métodos , Imagen de Difusión por Resonancia Magnética , Nervio Facial/diagnóstico por imagen , Nervio Facial/patología , Nervio Vestibulococlear/patología
6.
Environ Manage ; 72(3): 558-567, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37193747

RESUMEN

The value of sediment for helping coastal habitats and infrastructure respond to sea level rise is widely recognized. Across the country, coastal managers are seeking ways to beneficially use sediment sourced from dredging and other projects to counter coastal erosion and protect coastal resources. However, these projects are difficult to permit and have been slow to actualize. This paper draws on interviews with sediment managers and regulators in California to explore the challenges and opportunities for habitat restoration and beach nourishment within the current permitting regime. We find that permits are costly, difficult to obtain, and sometimes stand as a barrier to more sustainable and adaptive sediment management. We next characterize streamlining approaches and describe entities and ongoing efforts within California that apply them. Finally, we conclude that to keep pace with coastal losses due to climate change impacts, efforts toward efficient permitting must be accelerated and approaches diversified to support coastal resilience practices state-wide, in a timeframe that will allow coastal managers to innovate and adapt.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Cambio Climático , California
7.
J Am Acad Orthop Surg ; 31(7): e366-e375, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36951620

RESUMEN

Open transosseous rotator cuff repair (RCR) was the original benchmark surgical technique for RCR. The advent of arthroscopic and suture anchor technology shifted the paradigm from open to arthroscopic surgery. Although technological advances have progressed, they come at a cost. Suture anchor technology is expensive, optimal constructs have yet to be determined, and the technology may lead to challenging complications and revision scenarios. In more recent years, a return to transosseous bone tunnels has been described with new arthroscopic techniques, eliminating the need for suture anchors. The purpose of this article is to review the historical, biomechanical, clinical, and economic literature surrounding arthroscopic transosseous RCR.


Asunto(s)
Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Humanos , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/cirugía , Artroscopía/métodos , Técnicas de Sutura , Artroplastia , Anclas para Sutura , Fenómenos Biomecánicos
8.
Arthrosc Tech ; 11(7): e1261-e1267, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35936859

RESUMEN

Posterior shoulder instability is increasingly recognized and represents a complex continuum of pathology that can be challenging to diagnose and treat. Current surgical options involve posterior labral repair with or without capsular plication, as well as bony procedures, including glenoid bone grafting and glenoid osteotomy when indicated, often in the setting of revision. There is presently a dearth of surgical options to directly address the root cause of soft tissue failure, including a diminutive posterior labrum, chondrolabral retroversion, and thin or hyperelastic posterior capsule. This article presents a technique for arthroscopically augmenting the posterior capsulolabral complex in the setting of soft tissue insufficiency, laxity, or poor prognostic factors for failure. Secondarily, this technique provides a lower risk revision option for reconstruction in failed posterior instability without glenoid bone defect.

9.
Arthrosc Tech ; 11(7): e1247-e1250, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35936865

RESUMEN

There are many techniques described for biceps tenodesis that vary by fixation type, location, and open or arthroscopic method. Clinical outcomes are similar regardless of repair technique; therefore, the cost and time of procedures are increasingly points of improvement to practice value-based medicine and deliver cost-effective care. The technique described in this article builds on previous arthroscopic transosseous technical knowledge to yield a cost-effective and efficient clinical method to perform biceps tenodesis in the suprapectoral location without the cost and complications of an implant. In addition, this technique provides 4 methods of tenodesis in series, which serves to decrease the risk of mechanical failure and leverages the robust method of suture cerclage for capture of the biceps.

10.
Oper Neurosurg (Hagerstown) ; 22(5): e189-e197, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426878

RESUMEN

BACKGROUND: Despite the importance of complete, gross total resection (GTR) of fourth ventricular ependymomas, significant morbidity and/or subtotal resections are reported, particularly when the ventricular floor is infiltrated. Step-by-step technique descriptions are lacking in the literature. OBJECTIVE: To describe monitoring and stimulation mapping techniques and surgical nuances in the challenging subgroup of infiltrating fourth ventricular ependymomas by a highly illustrated, step-by-step description. Superimposed outlines of cranial nerve nuclei on the surgical field demonstrate critical anatomy and facilitate understanding in a way not previously presented. METHODS: We reviewed the microanatomical and neurophysiological prerequisites of resecting a diffusively infiltrating fourth ventricular ependymoma. RESULTS: We achieved GTR with the use of reproducible stimulating mapping and accurate cranial nerve nuclei identification. CONCLUSION: Enhanced microanatomical understanding, reproducible stimulation mapping, and meticulous resection techniques can result in GTR, even in diffusively infiltrating ependymomas.


Asunto(s)
Ependimoma , Procedimientos Neuroquirúrgicos , Nervios Craneales , Ependimoma/cirugía , Cuarto Ventrículo/cirugía , Humanos , Procedimientos Neuroquirúrgicos/métodos , Resultado del Tratamiento
11.
BMC Neurol ; 21(1): 287, 2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34301198

RESUMEN

BACKGROUND: Transsphenoidal surgery is the gold standard for pituitary adenoma resection. Although rare, a serious complication of surgery is worsened vision post-operatively. OBJECTIVE: To determine whether, in patients undergoing transsphenoidal surgery for pituitary adenoma, intraoperative monitoring of visual evoked potentials (VEP) is a safe, reproducible, and effective technological adjunct in predicting postoperative visual function. METHODS: The PubMed and OVID platforms were searched between January 1993 and December 2020 to identify publications that (1) featured patients undergoing transsphenoidal surgery for pituitary adenoma, (2) used intraoperative optic nerve monitoring with VEP and (3) reported on safety or effectiveness. Reference lists were cross-checked and expert opinion sought to identify further publications. RESULTS: Eleven studies were included comprising ten case series and one prospective cohort study. All employed techniques to improve reliability. No safety issues were reported. The only comparative study included described a statistically significant improvement in post-operative visual field testing when VEP monitoring was used. The remaining case-series varied in conclusion. In nine studies, surgical manipulation was halted in the event of a VEP amplitude decrease suggesting a widespread consensus that this is a warning sign of injury to the anterior optic apparatus. CONCLUSIONS: Despite limited and low-quality published evidence regarding intra-operative VEP monitoring, our review suggests that it is a safe, reproducible, and increasingly effective technique of predicting postoperative visual deficits. Further studies specific to transsphenoidal surgery are required to determine its utility in protecting visual function in the resection of complex pituitary tumours.


Asunto(s)
Potenciales Evocados Visuales , Monitorización Neurofisiológica Intraoperatoria , Neoplasias Hipofisarias , Humanos , Neoplasias Hipofisarias/cirugía , Estudios Prospectivos , Reproducibilidad de los Resultados , Resultado del Tratamiento , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología
12.
Sci Rep ; 11(1): 10150, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33980945

RESUMEN

Larval source management has gained renewed interest as a malaria control strategy in Africa but the widespread and transient nature of larval breeding sites poses a challenge to its implementation. To address this problem, we propose combining an integrated high resolution (50 m) distributed hydrological model and remotely sensed data to simulate potential malaria vector aquatic habitats. The novelty of our approach lies in its consideration of irrigation practices and its ability to resolve complex ponding processes that contribute to potential larval habitats. The simulation was performed for the year of 2018 using ParFlow-Common Land Model (CLM) in a sugarcane plantation in the Oromia region, Ethiopia to examine the effects of rainfall and irrigation. The model was calibrated using field observations of larval habitats to successfully predict ponding at all surveyed locations from the validation dataset. Results show that without irrigation, at least half of the area inside the farms had a 40% probability of potential larval habitat occurrence. With irrigation, the probability increased to 56%. Irrigation dampened the seasonality of the potential larval habitats such that the peak larval habitat occurrence window during the rainy season was extended into the dry season. Furthermore, the stability of the habitats was prolonged, with a significant shift from semi-permanent to permanent habitats. Our study provides a hydrological perspective on the impact of environmental modification on malaria vector ecology, which can potentially inform malaria control strategies through better water management.


Asunto(s)
Ecosistema , Malaria/epidemiología , Malaria/transmisión , Modelos Teóricos , Mosquitos Vectores/parasitología , Algoritmos , Animales , Vectores de Enfermedades , Etiopía/epidemiología , Geografía , Humanos , Hidrología , Larva , Malaria/parasitología , Estaciones del Año , Análisis Espacio-Temporal
13.
Arthrosc Tech ; 9(7): e947-e951, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32714803

RESUMEN

Biceps tenodesis is a well-accepted surgical treatment to relieve pain and dysfunction about the shoulder. Multiple locations and methods of tenodesis have been described, with similar outcomes. Transosseous cuff repairs and tendon repairs have been used for decades as a tried and true fixation method. This technique describes an arthroscopic transosseous technique for biceps tenodesis in the suprapectoral location that is technically simple, fast, eliminates the cost of implants, avoids an incision in the axillae which may be prone to dehiscence or infection, and releases the biceps sheath, which may be related to pain generation. Moreover, the biceps length tension relationship is easily recapitulated using anatomical landmarks.

15.
Arthrosc Tech ; 8(9): e1013-e1018, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31687334

RESUMEN

Transosseous repair has been used safely and effectively for primary and revision rotator cuff repair for decades; as a result, it is considered by many the historical gold standard of open repair techniques. Transosseous repair offers the advantage of excellent biology, double-row anatomic footprint reconstruction, and the ability to create multiple low-cost fixation points per surface area of tendon with high-strength suture, while avoiding anchor pullout, cyst formation, and imaging artifact. More recently, in arthroscopic applications, transosseous-equivalent anchor-based repairs have been introduced that have shown satisfactory clinical and biomechanical results; however, these attributes have been coupled with increased cost, nonbiologic burden to the healing interface of the tendon, and new catastrophic failure modes including tendon transection, anchor pullout, and bone voids. This article delineates a technique for arthroscopic true transosseous hybrid cuff repair that combines the use of anchors and transosseous techniques to maximize the benefits and minimize the detriments of both techniques. Level 1 (shoulder); level 2 (rotator cuff).

16.
Proc Natl Acad Sci U S A ; 114(37): 9785-9790, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28847932

RESUMEN

Sea level rise (SLR), a well-documented and urgent aspect of anthropogenic global warming, threatens population and assets located in low-lying coastal regions all around the world. Common flood hazard assessment practices typically account for one driver at a time (e.g., either fluvial flooding only or ocean flooding only), whereas coastal cities vulnerable to SLR are at risk for flooding from multiple drivers (e.g., extreme coastal high tide, storm surge, and river flow). Here, we propose a bivariate flood hazard assessment approach that accounts for compound flooding from river flow and coastal water level, and we show that a univariate approach may not appropriately characterize the flood hazard if there are compounding effects. Using copulas and bivariate dependence analysis, we also quantify the increases in failure probabilities for 2030 and 2050 caused by SLR under representative concentration pathways 4.5 and 8.5. Additionally, the increase in failure probability is shown to be strongly affected by compounding effects. The proposed failure probability method offers an innovative tool for assessing compounding flood hazards in a warming climate.


Asunto(s)
Cambio Climático , Inundaciones , Modelos Teóricos , Olas de Marea , Ciudades , Clima , Desastres , Humanos , Océanos y Mares , Estados Unidos
18.
Environ Sci Technol ; 49(19): 11264-80, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26317612

RESUMEN

Catchment urbanization perturbs the water and sediment budgets of streams, degrades stream health and function, and causes a constellation of flow, water quality, and ecological symptoms collectively known as the urban stream syndrome. Low-impact development (LID) technologies address the hydrologic symptoms of the urban stream syndrome by mimicking natural flow paths and restoring a natural water balance. Over annual time scales, the volumes of stormwater that should be infiltrated and harvested can be estimated from a catchment-scale water-balance given local climate conditions and preurban land cover. For all but the wettest regions of the world, a much larger volume of stormwater runoff should be harvested than infiltrated to maintain stream hydrology in a preurban state. Efforts to prevent or reverse hydrologic symptoms associated with the urban stream syndrome will therefore require: (1) selecting the right mix of LID technologies that provide regionally tailored ratios of stormwater harvesting and infiltration; (2) integrating these LID technologies into next-generation drainage systems; (3) maximizing potential cobenefits including water supply augmentation, flood protection, improved water quality, and urban amenities; and (4) long-term hydrologic monitoring to evaluate the efficacy of LID interventions.


Asunto(s)
Ciudades , Hidrología , Lluvia , Ríos , Filtración/instrumentación , Modelos Teóricos , Agua , Movimientos del Agua
19.
Environ Sci Technol ; 48(24): 14168-77, 2014 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-25390647

RESUMEN

Enclosed beaches along urban coastlines are frequent hot spots of fecal indicator bacteria (FIB) pollution. In this paper we present field measurements and modeling studies aimed at evaluating the impact of small storm drains on FIB pollution at enclosed beaches in Newport Bay, the second largest tidal embayment in Southern California. Our results suggest that small drains have a disproportionate impact on enclosed beach water quality for five reasons: (1) dry weather surface flows (primarily from overirrigation of lawns and ornamental plants) harbor FIB at concentrations exceeding recreational water quality criteria; (2) small drains can trap dry weather runoff during high tide, and then release it in a bolus during the falling tide when drainpipe outlets are exposed; (3) nearshore turbulence is low (turbulent diffusivities approximately 10(-3) m(2) s(-1)), limiting dilution of FIB and other runoff-associated pollutants once they enter the bay; (4) once in the bay, runoff can form buoyant plumes that further limit vertical mixing and dilution; and (5) local winds can force buoyant runoff plumes back against the shoreline, where water depth is minimal and human contact likely. Outdoor water conservation and urban retrofits that minimize the volume of dry and wet weather runoff entering the local storm drain system may be the best option for improving beach water quality in Newport Bay and other urban-impacted enclosed beaches.


Asunto(s)
Bacterias/aislamiento & purificación , Playas , Microbiología del Agua , Movimientos del Agua , Calidad del Agua , California , Monitoreo del Ambiente , Heces/microbiología , Modelos Teóricos , Estaciones del Año , Tiempo (Meteorología)
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