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2.
Accid Anal Prev ; 182: 106954, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36628883

RESUMEN

In this paper, we unpack the magnitude effects of the determinants of pedestrian crashes using a multivariate analysis approach. We consider four sets of exogenous factors that characterize residential neighborhoods as well as potentially affect pedestrian crashes and the racial composition of such crashes: (1) crash risk exposure (CE) attributes, (2) cultural variables, (3) built environment (BE) features, and (4) sociodemographic (SD) factors. Our investigation uses pedestrian crash and related data from the City of Houston, Texas, which we analyze at the spatial Census Block Group (CBG) level. Our results indicate that social resistance considerations (that is, minorities resisting norms as they are perceived as being set by the majority group), density of transit stops, and road design considerations (in particular in and around areas with high land-use diversity) are the three strongest determinants of pedestrian crashes, particularly in CBGs with a majority of the resident population being Black. The findings of this study can enable policymakers and planners to develop more effective countermeasures and interventions to contain the growing number of pedestrian crashes in recent years, as well as racial disparities in pedestrian crashes. Importantly, transportation safety engineers need to work with social scientists and engage with community leaders to build trust before leaping into implementing planning countermeasures and interventions. Issues of social resistance, in particular, need to be kept in mind.


Asunto(s)
Accidentes de Tránsito , Peatones , Humanos , Accidentes de Tránsito/prevención & control , Entorno Construido , Análisis Multivariante , Transportes
3.
Pediatr Cardiol ; 44(2): 280-296, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36125507

RESUMEN

The experience of diagnosis, decision-making and management in critical congenital heart disease is layered with complexity for both families and clinicians. We synthesise the current evidence regarding the family and healthcare provider experience of critical congenital heart disease diagnosis and management. A systematic integrative literature review was conducted by keyword search of online databases, MEDLINE (Ovid), PsycINFO, Cochrane, cumulative index to nursing and allied health literature (CINAHL Plus) and two journals, the Journal of Indigenous Research and Midwifery Journal from 1990. Inclusion and exclusion criteria were applied to search results with citation mining of final included papers to ensure completeness. Two researchers assessed study quality combining three tools. A third researcher reviewed papers where no consensus was reached. Data was coded and analysed in four phases resulting in final refined themes to summarise the findings. Of 1817 unique papers, 22 met the inclusion criteria. The overall quality of the included studies was generally good, apart from three of fair quality. There is little information on the experience of the healthcare provider. Thematic analysis identified three themes relating to the family experience: (1) The diagnosis and treatment of a critical congenital heart disease child significantly impacts parental health and wellbeing. (2) The way that healthcare and information is provided influences parental response and adaptation, and (3) parental responses and adaptation can be influenced by how and when support occurs. The experience of diagnosis and management of a critical congenital heart disease child is stressful and life-changing for families. Further research is needed into the experience of minority and socially deprived families, and of the healthcare provider, to inform potential interventions at the healthcare provider and institutional levels to improve family experience and support.


Asunto(s)
Atención a la Salud , Cardiopatías Congénitas , Niño , Humanos , Investigación Cualitativa , Padres , Personal de Salud , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/terapia
4.
J R Soc Interface ; 19(196): 20220671, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36415974

RESUMEN

The use of flying robots (drones) is increasing rapidly, but their utility is limited by high power demand, low specific energy storage and poor gust tolerance. By contrast, birds demonstrate long endurance, harvesting atmospheric energy in environments ranging from cluttered cityscapes to open landscapes, coasts and oceans. Here, we identify new opportunities for flying robots, drawing upon the soaring flight of birds. We evaluate mechanical energy transfer in soaring from first principles and review soaring strategies encompassing the use of updrafts (thermal or orographic) and wind gradients (spatial or temporal). We examine the extent to which state-of-the-art flying robots currently use each strategy and identify several untapped opportunities including slope soaring over built environments, thermal soaring over oceans and opportunistic gust soaring. In principle, the energetic benefits of soaring are accessible to flying robots of all kinds, given atmospherically aware sensor systems, guidance strategies and gust tolerance. Hence, while there is clear scope for specialist robots that soar like albatrosses, or which use persistent thermals like vultures, the greatest untapped potential may lie in non-specialist vehicles that make flexible use of atmospheric energy through path planning and flight control, as demonstrated by generalist flyers such as gulls, kites and crows.


Asunto(s)
Falconiformes , Robótica , Animales , Vuelo Animal , Aves , Viento
5.
Pediatr Ann ; 51(4): e161-e166, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35417309

RESUMEN

Adolescents and young adults (AYA) use social media more than any other generation, including to learn about their health. The coronavirus disease 2019 pandemic further accelerated both health harming and health benefits of technology use. Also, during this time, medical professionals moved more quickly to virtual visits, changing AYA, family, and provider interactions and expectations. Remote health care, broader technology use, and improved youth engagement have the potential to address long-standing barriers to health equity. Telehealth disadvantages still exist, however, especially for those with decreased access. Recent rapid changes have not allowed for sufficient study to address optimizing the experience, effectiveness, and utilization of remote health care. Fortunately, because of their expansive engagement with social media and technology, AYA are paving the way toward a digital health future. Health professionals are encouraged to improve their virtual and social media interactions with AYA patients, while finding ways to improve health equity. [Pediatr Ann. 2022;51(4):e161-e166.].


Asunto(s)
COVID-19 , Medios de Comunicación Sociales , Telemedicina , Adolescente , COVID-19/epidemiología , Humanos , Pandemias , SARS-CoV-2 , Adulto Joven
7.
Rev Sci Instrum ; 92(4): 045101, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243458

RESUMEN

A remote-operated apparatus for testing the detonation sensitivity of energetic materials is detailed. Using an air ram and rotating disk, the normal force and transverse velocity of the impact plane are controlled independently, enabling the exploration of varying impact conditions over a wide parameter space. A microcontroller local to the apparatus is used to automate apparatus operation and ensure temporal alignment of the impacting ram head with the rotating disk. Calculation of the firing parameters and issuing of operational commands are handled by a remote computer and relayed to the local microcontroller for execution at the hardware level. Impact forces are taken from fast strain measurements obtained from gauges incorporated into the ram head. Infrared imaging of explosive samples provides insight into the peak thermal temperatures experienced at the sample surface during the impact event.

8.
Int J Cardiol ; 337: 44-51, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33992700

RESUMEN

AIM: Coronary angiography is indicated in many patients with known or suspected angina for the investigation of coronary artery disease (CAD). However, up to half of patients with symptoms of ischaemia have no obstructive coronary arteries (INOCA). This large subgroup includes patients with suspected microvascular angina (MVA) and/or vasospastic angina (VSA). Clinical guidelines relating to the management of patients with INOCA are limited. Uncertainty regarding the diagnosis of patients with INOCA presents a health economic challenge, both in terms of healthcare resource utilisation and of quality-of-life impact on patients. METHODS: A cost-effectiveness analysis of the introduction of stratified medicine into the invasive management of INOCA, based on clinical and resource-use data obtained in the CorMicA trial, from a UK NHS perspective. The intervention included an invasive diagnostic procedure (IDP) of coronary vascular function during coronary angiography to define clinical endotypes to target with linked medical therapy. Outcomes of interest were mean total cost and QALY gain between treatment groups, and the incremental cost-effectiveness ratio. We undertook probabilistic sensitivity and scenario analyses. RESULTS: The incremental cost per QALY gained at 12 months was £4500 (£2937, £33264). Compared with a willingness-to-pay (WTP) threshold of £20,000 per QALY, the use of the IDP test is cost-effective. At this WTP threshold there is a 96% probability of the IDP being cost-effective, based on the uncertainty described by bootstrap analysis. CONCLUSIONS: The burden of INOCA, particularly in women, is known to be significant. These findings provided new evidence to inform this unmet clinical need.


Asunto(s)
Enfermedad de la Arteria Coronaria , Angina Microvascular , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Análisis Costo-Beneficio , Femenino , Humanos , Años de Vida Ajustados por Calidad de Vida
9.
Exp Mech ; 61(1): 263-283, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33814553

RESUMEN

BACKGROUND: Rupture of brain aneurysms is associated with high fatality and morbidity rates. Through remodeling of the collagen matrix, many aneurysms can remain unruptured for decades, despite an enlarging and evolving geometry. OBJECTIVE: Our objective was to explore this adaptive remodeling for the first time in an elastase induced aneurysm model in rabbits. METHODS: Saccular aneurysms were created in 22 New Zealand white rabbits and remodeling was assessed in tissue harvested 2, 4, 8 and 12 weeks after creation. RESULTS: The intramural principal stress ratio doubled after aneurysm creation due to increased longitudinal loads, triggering a remodeling response. A distinct wall layer with multi-directional collagen fibers developed between the media and adventitia as early as 2 weeks, and in all cases by 4 weeks with an average thickness of 50.6 ± 14.3 µm. Collagen fibers in this layer were multi-directional (AI = 0.56 ± 0.15) with low tortuosity (1.08 ± 0.02) compared with adjacent circumferentially aligned medial fibers (AI = 0.78 ± 0.12) and highly tortuous adventitial fibers (1.22 ± 0.03). A second phase of remodeling replaced circumferentially aligned fibers in the inner media with longitudinal fibers. A structurally motivated constitutive model with both remodeling modes was introduced along with methodology for determining material parameters from mechanical testing and multiphoton imaging. CONCLUSIONS: A new mechanism was identified by which aneurysm walls can rapidly adapt to changes in load, ensuring the structural integrity of the aneurysm until a slower process of medial reorganization occurs. The rabbit model can be used to evaluate therapies to increase aneurysm wall stability.

11.
Bioinspir Biomim ; 14(1): 016006, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30457112

RESUMEN

Fixed-wing small, unmanned aerial vehicles usually fly in atmospheric boundary layers that are often under the influence of turbulent environments. Inspired by nature's flyers, an application of an energy-harvesting flight strategy for increasing the energy state of the aircraft is presented. This paper provides basic longitudinal flight dynamic model exposing the physics behind the process. It shows significant power savings in flight with a sinusoidal and stochastic wind profile with active control of energy-harvesting. The active control based on optimized proportional gains was implemented for energy extraction from realistic atmospheric conditions, leading to significant energy savings for a 'bird-sized' vehicle. The paper reveals the equipment and necessary preparations for the flight test campaign. Moreover, it describes the design of a custom controller and its calibration in the wind tunnel against roll movements during pitching maneuvers. Finally, it investigates the benefits and potential of the automated process of energy-harvesting with simple proportional control through flight tests in a turbulent environment, validating the concept through the increased energy state of the aircraft.


Asunto(s)
Aeronaves/instrumentación , Aves/fisiología , Vuelo Animal/fisiología , Robótica/instrumentación , Alas de Animales/fisiología , Animales , Materiales Biomiméticos/química , Calibración , Simulación por Computador , Diseño de Equipo/instrumentación , Diseño de Equipo/métodos , Modelos Biológicos , Fenómenos Físicos
14.
Int J Cardiol ; 252: 24-30, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29249435

RESUMEN

BACKGROUND: Remote ischaemic preconditioning (RIPC) is a cardioprotective intervention invoking intermittent periods of ischaemia in a tissue or organ remote from the heart. The mechanisms of this effect are incompletely understood. We hypothesised that RIPC might enhance coronary vasodilatation by an endothelium-dependent mechanism. METHODS: We performed a prospective, randomised, sham-controlled, blinded clinical trial. Patients with stable coronary artery disease (CAD) undergoing elective invasive management were prospectively enrolled, and randomised to RIPC or sham (1:1) prior to angiography. Endothelial-dependent vasodilator function was assessed in a non-target coronary artery with intracoronary infusion of incremental acetylcholine doses (10-6, 10-5, 10-4mol/l). Venous blood was sampled pre- and post-RIPC or sham, and analysed for circulating markers of endothelial function. Coronary luminal diameter was assessed by quantitative coronary angiography. The primary outcome was the between-group difference in the mean percentage change in coronary luminal diameter following the maximal acetylcholine dose (Clinicaltrials.gov identifier: NCT02666235). RESULTS: 75 patients were enrolled. Following angiography, 60 patients (mean±SD age 57.5±8.5years; 80% male) were eligible and completed the protocol (n=30 RIPC, n=30 sham). The mean percentage change in coronary luminal diameter was -13.3±22.3% and -2.0±17.2% in the sham and RIPC groups respectively (difference 11.32%, 95%CI: 1.2- 21.4, p=0.032). This remained significant when age and sex were included as covariates (difference 11.01%, 95%CI: 1.01- 21.0, p=0.035). There were no between-group differences in endothelial-independent vasodilation, ECG parameters or circulating markers of endothelial function. CONCLUSIONS: RIPC attenuates the extent of vasoconstriction induced by intracoronary acetylcholine infusion. This endothelium-dependent mechanism may contribute to the cardioprotective effects of RIPC.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Precondicionamiento Isquémico Miocárdico/métodos , Anciano , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Electrocardiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Método Simple Ciego , Resultado del Tratamiento
16.
J Dent Res ; 96(11): 1290-1297, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28813629

RESUMEN

The Eda pathway ( Eda, Edar, Edaradd) plays an important role in tooth development, determining tooth number, crown shape, and enamel formation. Here we show that the Eda pathway also plays a key role in root development. Edar (the receptor) is expressed in Hertwig's epithelial root sheath (HERS) during root development, with mutant mice showing a high incidence of taurodontism: large pulp chambers lacking or showing delayed bifurcation or trifurcation of the roots. The mouse upper second molars in the Eda pathway mutants show the highest incidence of taurodontism, this enhanced susceptibility being matched in human patients with mutations in EDA-A1. These taurodont teeth form due to defects in the direction of extension of the HERS from the crown, associated with a more extensive area of proliferation of the neighboring root mesenchyme. In those teeth where the angle at which the HERS extends from the crown is very wide and therefore more vertical, the mutant HERSs fail to reach toward the center of the tooth in the normal furcation region, and taurodont teeth are created. The phenotype is variable, however, with milder changes in angle and proliferation leading to normal or delayed furcation. This is the first analysis of the role of Eda in the root, showing a direct role for this pathway during postnatal mouse development, and it suggests that changes in proliferation and angle of HERS may underlie taurodontism in a range of syndromes.


Asunto(s)
Cavidad Pulpar/anomalías , Ectodisplasinas/genética , Diente Molar/anomalías , Diente Molar/embriología , Anomalías Dentarias/genética , Raíz del Diente/anomalías , Raíz del Diente/embriología , Adolescente , Animales , Niño , Humanos , Masculino , Ratones , Odontogénesis/genética , Fenotipo , Transducción de Señal , Microtomografía por Rayos X
17.
Poult Sci ; 96(8): 2862-2870, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28419339

RESUMEN

Poultry waterlines are constructed using polyvinylchloride (PVC) material on which bacterial biofilm can easily form. Biofilm can harbor pathogens including avian pathogenic E. coli (APEC) strains. An in vitro evaluation was performed to determine if E. coli sero group O2 (avian pathogenic) could attach on a PVC surface that had pre-formed biofilm and if this phenomenon could be affected when water was treated with chlorine. Initially, biofilm growth was induced in PVC test coupons (15.16 cm2) for a 7-day period mimicking the waterline scenario in the first wk of poultry brooding; and then this biofilm was challenged with E. coli O2 seeded water in presence/absence of chlorine treatment. After rinsing, test coupons were sampled for bacterial (APC) and E. coli O2 enumeration at various occasions post seeding the pathogen and chlorine treatment. Day 7 APC recovered from coupons was 4.35 log10 cfu/cm2 in trial 1 and 3.66 log10 cfu/cm2 in trial 2. E. coli O2 was not recovered from chlorine treated test coupons (P < 0.05), whereas it was retrieved from untreated coupons (untreated contained > 3 log10 cfu/cm2 in trial 1 and > 2 log10 cfu/cm2 in trial 2). This study suggests that E. coli O2 can incorporate into pre-formed biofilm on a PVC surface within 24 h if water sanitation is not present, and the attachment time of the pathogen can prolong in the absence of already formed biofilm.


Asunto(s)
Biopelículas/efectos de los fármacos , Cloro/farmacología , Desinfectantes/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Microbiología del Agua , Abastecimiento de Agua , Crianza de Animales Domésticos , Animales , Pollos , Calor , Vivienda para Animales , Movimientos del Agua
18.
Poult Sci ; 96(7): 2145-2150, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28339699

RESUMEN

An in vitro experiment was performed to determine if biofilm would develop when polyvinylchloride (PVC) test coupons (material used for poultry waterlines) were exposed to low bacterial content warm water (≤1000 cfu/mL, test water) and also to determine if biofilm development would be influenced by adding a sanitizer. PVC sections 2.54 cm long and internal diameter of 1. 90 cm were used as test coupons to grow biofilm. Two coupons were immersed in 600 mL test water in a beaker. Nine beakers were utilized similarly with a total of 18 coupons. Three beakers (T1) were treated with a chlorine (Cl) based product (targeted to produce 2 to 4 ppm residual) and the other 3 (T2) with hydrogen peroxide a (HP) based product (targeted to produce 25 to 50 ppm residual). Three untreated beakers served as controls (T3). All beakers and coupons were placed into a water bath shaker under warm and moving water conditions mimicking poultry brooding conditions. Coupons and test water were sampled for treatments for aerobic plate count (APC). Trial 1 used test water with zero cfu bacteria/mL initial APC, whereas the Trial 2 test water initial APC was 3 log10 cfu/mL. Test water samples and coupons had no bacterial growth for all treatments on sampling occasions for Trial 1. In Trial 2, T3 (control) and T2 (HP treated) had APC growth in both test water (2.5 to 3.0 log10 cfu/mL) and on coupons (2 to 2.5 log10 cfu/cm2) on sampling d with no difference (P > 0.05) between these treatments. Whereas, T1 (Cl treated) eliminated bacteria (zero cfu/mL) in test water and inhibited biofilm growth on test coupons (≤0.2 log10 cfu/cm2) during sampling d (P < 0.05). This experiment showed that biofilm can develop in minimally contaminated water even in the presence of sanitizers, yet chlorine was more effective than hydrogen peroxide in limiting this development.


Asunto(s)
Crianza de Animales Domésticos , Biopelículas/efectos de los fármacos , Cloro/farmacología , Desinfectantes/farmacología , Desinfección , Peróxido de Hidrógeno/farmacología , Microbiología del Agua , Animales , Vivienda para Animales , Cloruro de Polivinilo/química , Aves de Corral , Estados Unidos , Abastecimiento de Agua
19.
Poult Sci ; 96(3): 560-565, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-27920190

RESUMEN

Formaldehyde is commonly used to overcome contaminants introduced by hatching eggs or water supply in the hatcher cabinets. However, health risks associated with its use make economical alternatives important. This project evaluated a chlorine dioxide based product (CDBP) (0.3% concentrate) as a hatchery sanitizer in decontaminating microbial populations on the shell surface of hatching eggs (>18 d old), as well as its impact on hatchability and chick performance. Hatchers (0.20 m2) designed to hold approximately 50 eggs and equipped with circulation fans, heaters, and thermostats were used for the evaluation. For each of the 2 trials conducted, 450 hatching eggs were obtained and incubated in a common setter. Eggs used in trial 1 were floor eggs whereas in trial 2 nest eggs were used. On d 18 of incubation, eggs were removed from the setter, and viable eggs were randomly allocated to 9 hatchers. Pre-treatment egg rinse samples (10 eggs per hatcher) were collected for initial microbial analysis. Three hatchers were treated with CDBP and 3 hatchers with a formaldehyde based product (FBP). Three untreated hatchers served as control (C). Prior to hatch, 10 eggs/incubator, not previously rinsed, were used for post treatment microbial counts. The hatched chicks were reared until d 21 in floor pens with a common starter diet. For the CDBP treated eggs, hatchability and chick performance (weight gains, mortality, and FCR on d 7 and d 21) were similar to the other treatments. The application rate of CDBP evaluated in this study was not an effective antimicrobial alternative to formaldehyde for sanitizing hatching eggs in hatcher cabinets prior to hatch.


Asunto(s)
Crianza de Animales Domésticos/métodos , Pollos , Compuestos de Cloro , Desinfección , Óxidos , Animales , Desinfectantes , Formaldehído , Óvulo
20.
Cell Death Differ ; 23(7): 1140-51, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26742431

RESUMEN

Mitophagy is critical for cell homeostasis. Externalization of the inner mitochondrial membrane phospholipid, cardiolipin (CL), to the surface of the outer mitochondrial membrane (OMM) was identified as a mitophageal signal recognized by the microtubule-associated protein 1 light chain 3. However, the CL-translocating machinery remains unknown. Here we demonstrate that a hexameric intermembrane space protein, NDPK-D (or NM23-H4), binds CL and facilitates its redistribution to the OMM. We found that mitophagy induced by a protonophoric uncoupler, carbonyl cyanide m-chlorophenylhydrazone (CCCP), caused externalization of CL to the surface of mitochondria in murine lung epithelial MLE-12 cells and human cervical adenocarcinoma HeLa cells. RNAi knockdown of endogenous NDPK-D decreased CCCP-induced CL externalization and mitochondrial degradation. A R90D NDPK-D mutant that does not bind CL was inactive in promoting mitophagy. Similarly, rotenone and 6-hydroxydopamine triggered mitophagy in SH-SY5Y cells was also suppressed by knocking down of NDPK-D. In situ proximity ligation assay (PLA) showed that mitophagy-inducing CL-transfer activity of NDPK-D is closely associated with the dynamin-like GTPase OPA1, implicating fission-fusion dynamics in mitophagy regulation.


Asunto(s)
Cardiolipinas/metabolismo , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Mitofagia , Nucleósido Difosfato Quinasa D/metabolismo , Animales , Autofagia/efectos de los fármacos , Carbonil Cianuro m-Clorofenil Hidrazona/toxicidad , Cardiolipinas/análisis , Línea Celular , GTP Fosfohidrolasas/metabolismo , Células HeLa , Humanos , Lisosomas/metabolismo , Lisosomas/patología , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias/patología , Mitofagia/efectos de los fármacos , Mutagénesis Sitio-Dirigida , Nucleósido Difosfato Quinasa D/antagonistas & inhibidores , Nucleósido Difosfato Quinasa D/genética , Oxidopamina/farmacología , Unión Proteica , Interferencia de ARN , Rotenona/farmacología
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