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1.
Sensors (Basel) ; 23(10)2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37430795

RESUMEN

Functional objects are large and small physical entities installed in urban environments to offer specific functionalities to visitors, such as shops, escalators, and information kiosks. Instances of the novel notion are focal points of human activities and are significant in pedestrian movement. Pedestrian trajectory modelling in an urban scene is a challenging problem because of the complex patterns resulting from social interactions of the crowds and the diverse relation between pedestrians and functional objects. Many data-driven methods have been proposed to explain the complex movements in urban scenes. However, the methods considering functional objects in their formulation are rare. This study aims to reduce the knowledge gap by demonstrating the importance of pedestrian-object relations in the modelling task. The proposed modelling method, called pedestrian-object relation guided trajectory prediction (PORTP), uses a dual-layer architecture that includes a predictor of pedestrian-object relation and a series of relation-specific specialized pedestrian trajectory prediction models. The experiment findings indicate that the inclusion of pedestrian-object relation results in more accurate predictions. This study provides an empirical foundation for the novel notion and a strong baseline for future work on this topic.

2.
Angew Chem Int Ed Engl ; 54(40): 11677-80, 2015 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-26288217

RESUMEN

The first example of a transition-metal-catalyzed, meta-selective C-H bromination procedure is reported. In the presence of catalytic [{Ru(p-cymene)Cl2 }2 ], tetrabutylammonium tribromide can be used to functionalize the meta C-H bond of 2-phenylpyridine derivatives, thus affording difficult to access products which are highly predisposed to further derivatization. We demonstrate this utility with one-pot bromination/arylation and bromination/alkenylation procedures to deliver meta-arylated and meta-alkenylated products, respectively, in a single step.

3.
Semin Neurol ; 34(5): 534-41, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25520025

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting 20,000 to 30,000 people in the United States. The mainstay of care of patients affected by this disease is supportive and given the multifaceted nature of their needs is provided most efficiently through multidisciplinary clinics that have shown to prolong survival and improve quality of life. The authors discuss in detail evidence-based management of individuals affected by this condition.


Asunto(s)
Actividades Cotidianas , Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/terapia , Adulto , Nutrición Enteral/métodos , Terapia por Ejercicio/métodos , Humanos , Masculino , Aparatos Ortopédicos/estadística & datos numéricos , Respiración Artificial/métodos
4.
Adv Sci (Weinh) ; 9(16): e2105723, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35404540

RESUMEN

The performance of Li+ ion batteries (LIBs) is hindered by steep Li+ ion concentration gradients in the electrodes. Although thick electrodes (≥300 µm) have the potential for reducing the proportion of inactive components inside LIBs and increasing battery energy density, the Li+ ion concentration gradient problem is exacerbated. Most understanding of Li+ ion diffusion in the electrodes is based on computational modeling because of the low atomic number (Z) of Li. There are few experimental methods to visualize Li+ ion concentration distribution of the electrode within a battery of typical configurations, for example, coin cells with stainless steel casing. Here, for the first time, an interrupted in situ correlative imaging technique is developed, combining novel, full-field X-ray Compton scattering imaging with X-ray computed tomography that allows 3D pixel-by-pixel mapping of both Li+ stoichiometry and electrode microstructure of a LiNi0.8 Mn0.1 Co0.1 O2 cathode to correlate the chemical and physical properties of the electrode inside a working coin cell battery. An electrode microstructure containing vertically oriented pore arrays and a density gradient is fabricated. It is shown how the designed electrode microstructure improves Li+ ion diffusivity, homogenizes Li+ ion concentration through the ultra-thick electrode (1 mm), and improves utilization of electrode active materials.

5.
Cureus ; 13(5): e14844, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-34104589

RESUMEN

Background and objective  Fast neutron radiotherapy (NRT) is a high linear energy transfer (LET) particle therapy that offers a local control (LC) advantage over low-LET X-rays in the treatment of advanced and unresectable salivary gland malignancies. However, in tumors approximating the base of skull (BOS), target volumes may be underdosed to minimize toxicity to the central nervous system (CNS). In this setting, a proton beam boost to the underdosed part of the tumor may improve LC. We report our early experience with a hybrid neutron-proton approach in patients with BOS involvement. Materials and methods We retrospectively reviewed 29 patients with locally advanced and unresectable salivary gland tumors involving the BOS between 2014-2018. The median age of the patients was 56 years, with the majority of them having adenoid cystic carcinomas (ACC) (79%) with advanced T4a/b disease (86%), pathologic perineural invasion (PNI) (55.2%), and orbital invasion (34.5%). Five patients (17.2%) were cases of re-irradiation. Surgical resection was attempted in 15 patients (51.7%), of which none achieved negative margins. The median neutron dose was 18.4 neutron Gray (nGy) with a sequential proton boost (PB) with a median dose of 25 Gy [relative biological effectiveness (RBE)] (range: 16-45 Gy). Toxicity was graded per the Common Terminology Criteria for Adverse Events (CTCAE) version 4.03. Descriptive statistics and the Kaplan-Meier method were used. Results At a median follow-up of 18.9 months [interquartile range (IQR): 6.1-32.5], the entire cohort's overall survival (OS) was 93.1%, progression-free survival (PFS) was 79.3%, and LC was 89.7%. Among patients who were not re-irradiated (n=24), the most commonly recorded acute grade 3 toxicities were mucositis (50%) and dermatitis (37.5%). There was no documented acute grade 4/5 events. Late grade 3/4 events included trismus (n=1), hearing loss (n=2), visual loss (n=6), and bone necrosis (n=1). There were no reported late grade 5 events in de novo patients. Conclusion In this challenging cohort with a poor prognosis, early outcomes for a hybrid neutron-proton approach were found to be promising. Further studies involving longer follow-ups with a larger cohort of patients are required to validate our findings.

6.
Sci Adv ; 4(4): eaar4004, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29662954

RESUMEN

The crystallization of solidifying Al-Cu alloys over a wide range of conditions was studied in situ by synchrotron x-ray radiography, and the data were analyzed using a computer vision algorithm trained using machine learning. The effect of cooling rate and solute concentration on nucleation undercooling, crystal formation rate, and crystal growth rate was measured automatically for thousands of separate crystals, which was impossible to achieve manually. Nucleation undercooling distributions confirmed the efficiency of extrinsic grain refiners and gave support to the widely assumed free growth model of heterogeneous nucleation. We show that crystallization occurred in temporal and spatial bursts associated with a solute-suppressed nucleation zone.

7.
Eur J Cancer ; 89: 56-63, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29227818

RESUMEN

BACKGROUND: Although the neutrophil-lymphocyte ratio (NLR) is prognostic in many oncological settings, its significance in the immunotherapy era is unknown. Mechanistically, PD-1/PD-L1 inhibitors may alter NLR. We sought to characterise NLR kinetics in patients with advanced solid tumours treated with PD-1/PD-L1 inhibitors. METHODS: Electronic records of patients treated with PD-1/PD-L1 inhibitors on phase I trials across three sites were reviewed. A high NLR (hNLR) was predefined as >5. Univariate logistic regression models were used for toxicity, response analyses and Cox models for overall survival (OS) and progression-free survival analyses. Landmark analyses were performed (cycle two, three). Longitudinal analysis of NLR was performed utilising a mixed effect regression model. RESULTS: The median OS for patients with hNLR was 8.5 months and 19.4 for patients with low NLR, (hazard ratio [HR] = 1.85, 95% confidence interval [CI] 1.15-2.96, p = 0.01). On landmark analysis, hNLR was significantly associated with inferior OS at all time points with a similar magnitude of effect over time (p < 0.05). On multivariate analysis, NLR was associated with OS (HR 1.06, 95% CI 1.01-1.11, p = 0.01). NLR did not correlate with increased immune toxicity. Longitudinally, NLR correlated with response: NLR decreased by 0.09 (95% CI: -0.15 to -0.02; p = 0.01) per month in responders compared with non-responders. CONCLUSIONS: hNLR at baseline and during treatment is adversely prognostic in patients with advanced malignancies receiving PD-1/PD-L1 blockade. Importantly, NLR reduced over time in responders to immunotherapy. Taken together, these data suggest that baseline and longitudinal NLR may have utility as a unique biomarker to aid clinical decision-making in patients receiving immunotherapy.


Asunto(s)
Antígeno B7-H1/antagonistas & inhibidores , Linfocitos , Neoplasias/tratamiento farmacológico , Neutrófilos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias/inmunología , Neoplasias/mortalidad
8.
Am J Infect Control ; 44(5): 579-86, 2016 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-26831273

RESUMEN

BACKGROUND: The use of N95 respirators prevents spread of respiratory infectious agents, but leakage hampers its protection. Manufacturers recommend a user seal check to identify on-site gross leakage. However, no empirical evidence is provided. Therefore, this study aims to examine validity of a user seal check on gross leakage detection in commonly used types of N95 respirators. METHODS: A convenience sample of 638 nursing students was recruited. On the wearing of 3 different designs of N95 respirators, namely 3M-1860s, 3M-1862, and Kimberly-Clark 46827, the standardized user seal check procedure was carried out to identify gross leakage. Repeated testing of leakage was followed by the use of a quantitative fit testing (QNFT) device in performing normal breathing and deep breathing exercises. Sensitivity, specificity, predictive values, and likelihood ratios were calculated accordingly. RESULTS: As indicated by QNFT, prevalence of actual gross leakage was 31.0%-39.2% with the 3M respirators and 65.4%-65.8% with the Kimberly-Clark respirator. Sensitivity and specificity of the user seal check for identifying actual gross leakage were approximately 27.7% and 75.5% for 3M-1860s, 22.1% and 80.5% for 3M-1862, and 26.9% and 80.2% for Kimberly-Clark 46827, respectively. Likelihood ratios were close to 1 (range, 0.89-1.51) for all types of respirators. CONCLUSIONS: The results did not support user seal checks in detecting any actual gross leakage in the donning of N95 respirators. However, such a check might alert health care workers that donning a tight-fitting respirator should be performed carefully.


Asunto(s)
Falla de Equipo , Personal de Salud , Autoexamen/métodos , Ventiladores Mecánicos , Adolescente , Adulto , Animales , Estudios Transversales , Femenino , Humanos , Masculino , Estudios Prospectivos , Sensibilidad y Especificidad , Estudiantes de Enfermería , Adulto Joven
9.
Arthritis Care Res (Hoboken) ; 68(2): 151-66, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26401907

RESUMEN

OBJECTIVE: To provide evidence-based recommendations for the treatment of patients with ankylosing spondylitis (AS) and nonradiographic axial spondyloarthritis (SpA). METHODS: A core group led the development of the recommendations, starting with the treatment questions. A literature review group conducted systematic literature reviews of studies that addressed 57 specific treatment questions, based on searches conducted in OVID Medline (1946-2014), PubMed (1966-2014), and the Cochrane Library. We assessed the quality of evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method. A separate voting group reviewed the evidence and voted on recommendations for each question using the GRADE framework. RESULTS: In patients with active AS, the strong recommendations included use of nonsteroidal antiinflammatory drugs (NSAIDs), use of tumor necrosis factor inhibitors (TNFi) when activity persists despite NSAID treatment, not to use systemic glucocorticoids, use of physical therapy, and use of hip arthroplasty for patients with advanced hip arthritis. Among the conditional recommendations was that no particular TNFi was preferred except in patients with concomitant inflammatory bowel disease or recurrent iritis, in whom TNFi monoclonal antibodies should be used. In patients with active nonradiographic axial SpA despite treatment with NSAIDs, we conditionally recommend treatment with TNFi. Other recommendations for patients with nonradiographic axial SpA were based on indirect evidence and were the same as for patients with AS. CONCLUSION: These recommendations provide guidance for the management of common clinical questions in AS and nonradiographic axial SpA. Additional research on optimal medication management over time, disease monitoring, and preventive care is needed to help establish best practices in these areas.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Espondilitis Anquilosante/tratamiento farmacológico , Humanos , Educación del Paciente como Asunto , Espondilitis Anquilosante/complicaciones , Espondilitis Anquilosante/rehabilitación
10.
Arthritis Rheumatol ; 68(2): 282-98, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26401991

RESUMEN

OBJECTIVE: To provide evidence-based recommendations for the treatment of patients with ankylosing spondylitis (AS) and nonradiographic axial spondyloarthritis (SpA). METHODS: A core group led the development of the recommendations, starting with the treatment questions. A literature review group conducted systematic literature reviews of studies that addressed 57 specific treatment questions, based on searches conducted in OVID Medline (1946-2014), PubMed (1966-2014), and the Cochrane Library. We assessed the quality of evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method. A separate voting group reviewed the evidence and voted on recommendations for each question using the GRADE framework. RESULTS: In patients with active AS, the strong recommendations included use of nonsteroidal antiinflammatory drugs (NSAIDs), use of tumor necrosis factor inhibitors (TNFi) when activity persists despite NSAID treatment, not to use systemic glucocorticoids, use of physical therapy, and use of hip arthroplasty for patients with advanced hip arthritis. Among the conditional recommendations was that no particular TNFi was preferred except in patients with concomitant inflammatory bowel disease or recurrent iritis, in whom TNFi monoclonal antibodies should be used. In patients with active nonradiographic axial SpA despite treatment with NSAIDs, we conditionally recommend treatment with TNFi. Other recommendations for patients with nonradiographic axial SpA were based on indirect evidence and were the same as for patients with AS. CONCLUSION: These recommendations provide guidance for the management of common clinical questions in AS and nonradiographic axial SpA. Additional research on optimal medication management over time, disease monitoring, and preventive care is needed to help establish best practices in these areas.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Antirreumáticos/uso terapéutico , Artroplastia de Reemplazo de Cadera , Modalidades de Fisioterapia , Reumatología/normas , Espondilitis Anquilosante/terapia , Adalimumab/uso terapéutico , Etanercept/uso terapéutico , Medicina Basada en la Evidencia , Glucocorticoides/uso terapéutico , Humanos , Enfermedades Inflamatorias del Intestino/complicaciones , Infliximab/uso terapéutico , Radiografía , Sociedades Médicas , Espondiloartritis/complicaciones , Espondiloartritis/diagnóstico por imagen , Espondiloartritis/terapia , Espondiloartropatías/complicaciones , Espondiloartropatías/diagnóstico por imagen , Espondiloartropatías/terapia , Espondilitis Anquilosante/complicaciones , Espondilitis Anquilosante/diagnóstico por imagen , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Estados Unidos
11.
J Neurol Phys Ther ; 33(2): 68-87, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19556916

RESUMEN

BACKGROUND AND PURPOSE: Amyotrophic lateral sclerosis (ALS) is an idiopathic disease of adults affecting upper and lower motor neurons. In one to four years, progressive weakness, spasticity, and respiratory insufficiency compromise independence and survival. Current medical treatment is limited to medication and supportive care. The benefit and harm of moderate physical exercise are controversial. This review examined current research related to moderate exercise for maintaining independence without accelerating disease progression in persons with ALS. METHODS: An evidence-based search was conducted using keywords alone and in combination (ALS, exercise, Lou Gehrig's disease, physical therapy) to search PubMed, PEDro, Hooked on Evidence, Ovid, and Cochrane databases. Human and animal models were included and graded on level of evidence and strength of recommendations for developing guidelines to practice. A secondary reviewer evaluated all selected studies, and statistics were calculated. RESULTS: The search yielded the following nine studies: four small clinical studies, one clinical systematic review, and four randomized, controlled trials based on animal models. In human studies, there were small to moderate effect sizes supporting the benefit of moderate exercise in persons with early-stage ALS, with no adverse affects on disease progression or survival time. In transgenic mice with superoxide dismutase-1 ALS, moderate exercise most often had a moderate effect size for increasing life span. DISCUSSION AND CONCLUSION: Large randomized clinical trials are needed to develop specific exercise guidelines. However, evidence suggests that moderate exercise is not associated with adverse outcomes in persons with early-stage ALS. Moderate exercise programs can be safely adapted to abilities, interests, specific response to exercise, accessibility, and family support.


Asunto(s)
Esclerosis Amiotrófica Lateral/rehabilitación , Terapia por Ejercicio/métodos , Animales , Progresión de la Enfermedad , Humanos
12.
J Neurophysiol ; 88(2): 613-20, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12163514

RESUMEN

In the event of an unexpected disturbance to balance, the ability to recover a stable upright stance should depend not only on the magnitude of torque that can be generated by contraction of muscles spanning the lower extremity joints but also on how quickly these torques can be developed. In the present study, we used a combination of experimental and mathematical models of balance recovery by sway (feet in place responses) to test this hypothesis. Twenty-three young subjects participated in experiments in which they were supported in an inclined standing position by a horizontal tether and instructed to recover balance by contracting only their ankle muscles. The maximum lean angle where they could recover balance without release of the tether (static recovery limit) averaged 14.9 +/- 1.4 degrees (mean +/- SD). The maximum initial lean angle where they could recover balance after the tether was unexpectedly released and the ankles were initially relaxed (dynamic recovery limit) averaged 5.9 +/- 1.1 degrees, or 60 +/- 11% smaller than the static recovery limit. Peak ankle torque did not differ significantly between the two conditions (and averaged 116 +/- 32 Nm), indicating the strong effect on recovery ability of latencies in the onset and subsequent rates of torque generation (which averaged 99 +/- 13 ms and 372 +/- 267 N. m/s, respectively). Additional experiments indicated that dynamic recovery limits increased 11 +/- 14% with increases in the baseline ankle torques prior to release (from an average value of 31 +/- 18 to 54 +/- 24 N. m). These trends are in agreement with predictions from a computer simulation based on an inverted pendulum model, which illustrate the specific combinations of baseline ankle torque, rate of torque generation, and peak ankle torque that are required to attain target recovery limits.


Asunto(s)
Tobillo , Equilibrio Postural/fisiología , Torque , Adolescente , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Modelos Teóricos
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