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1.
Opt Lett ; 45(3): 623-626, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32004267

##### RESUMO

Phase birefringence in optical fibers typically fluctuates over their length due to geometrical imperfections induced from the drawing process or during installation. Currently commercially available fibers exhibit remarkably low birefringence, prompting a high standard for characterization methods. In this work, we detail a method that uses chirped-pulse phase-sensitive optical time-domain reflectometry to directly measure position-resolved linear birefringence of single-mode optical fibers. The technique is suitable for fiber characterization over lengths of tens of kilometers, relying on a fast measurement (${\sim} 1\,\, {\rm s}$â¼1s) with single-ended access to the fiber. The proposed method is experimentally validated with three different commercial single-mode optical fibers.

2.
Contemp Clin Trials ; : 105956, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32061969

##### RESUMO

BACKGROUND: Community-based programs have had modest success in combating obesity in Latino populations. Latino families' norms and beliefs about weight often hold larger body sizes to be normal, leading to lower engagement in weight-focused programs. Because improvements in cardiorespiratory fitness confer health benefits, regardless of weight, they offer an alternative to obesity-focused approaches. We describe the rationale and design of Athletes for Life (AFL), a community- and family-based intervention for Latino families. METHODS/DESIGN: This two-group randomized controlled trial will test the efficacy of AFL for improving cardiorespiratory fitness and diet in 6- to 11-year-old children (Nâ¯=â¯160) and their parents, relative to a wait-list control group. Children will participate in 12â¯weeks of semiweekly sports skill programing and nutrition sessions. Concurrently, parents will participate in sports-focused activity and behavior change sessions that focus on nutrition, chronic disease prevention, and healthy eating. Cardiovascular fitness will be measured by the 1-mile run and 3-min step-test for both parents and children. Secondary outcomes include changes in objectively measured physical activity, dietary measures, body composition, and cardiometabolic risk (waist circumference, blood pressure, blood lipids, glucose, insulin, and C-reactive protein). DISCUSSION: AFL, implemented with a strong community partnership, will provide a test of the efficacy of culturally tailored intervention programming to promote positive health behaviors and improve health outcomes in Latino families. Intervention content, structure, and messaging will provide guidance for future methods to engage Latino families in health promotion programs that highlight their cultural norms, and beliefs. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT03761589 (12/3/2018).

3.
Sensors (Basel) ; 20(3)2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32046270

##### RESUMO

Until recently, the amount of solar irradiance reaching the Earth surface was considered to be a steady value over the years. However, there is increasing observational evidence showing that this quantity undergoes substantial variations over time, which need to be addressed in different scenarios ranging from climate change to solar energy applications. With the growing interest in developing solar energy technology with enhanced efficiency and optimized management, the monitoring of solar irradiance at the ground level is now considered to be a fundamental input in the pursuit of that goal. Here, we propose the first fiber-based distributed sensor able of monitoring ground solar irradiance in real time, with meter scale spatial resolutions over distances of several tens of kilometers (up to 100 km). The technique is based on an optical fiber reflectometry technique (CP-ÏOTDR), which enables real time and long-range high-sensitivity bolometric measurements of solar radiance with a single optical fiber cable and a single interrogator unit. The method is explained and analyzed theoretically. A validation of the method is proposed using a solar simulator irradiating standard optical fibers, where we demonstrate the ability to detect and quantify solar irradiance with less than a 0.1 W/m2 resolution.

4.
Appetite ; 144: 104482, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593746

##### RESUMO

OBJECTIVE: To examine if first-year roommates made similar meal plan decisions. METHODS: Residence information for 1186 first-year students (Nâ¯=â¯593 roommate pairs) and 559 floormates was obtained for the 2015-2016 academic year. Linear generalized estimating equations (GEEs) were used to examine if the number of meals students used over the semester was higher if their roommate used their meal plan more frequently. A logistic GEE examined joint meal plan usage between students and roommates for each month of the semester. To determine if residence, rather than roommate, explained the results, a simulation was conducted by randomly assigning the floormates to a same-sex roommate. RESULTS: The number of meals students used in spring was higher if the students' roommate had used more meals in spring, even after controlling for the number of meals students used in fall (Female: ßâ¯=â¯0.07, 99% CIâ¯=â¯0.00, 0.13; Male: ßâ¯=â¯0.10, 99% CIâ¯=â¯0.02, 0.18). Students were more likely to use a meal with their roommate if they were on the same meal plan (Female: ORâ¯=â¯1.61, 99% CIâ¯=â¯1.27, 2.04; Male: ORâ¯=â¯1.57, 99% CIâ¯=â¯1.09, 2.25), and less likely after the first month of being roommates (Female: ORâ¯=â¯0.57-0.25; Male: ORâ¯=â¯0.50-0.22; pâ¯<â¯0.001). The simulation analysis indicated these findings were not due to shared residence. DISCUSSION: Students' meal plan choices were associated with their roommates' meal plan choices. Roommates' joint meal plan usage was highest at the start of the year. Strategic roommate pairings may result in students using their meal plan more. Further research should determine the extent of roommate influence on students' diet.

5.
Contemp Clin Trials ; 89: 105914, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31843638

##### RESUMO

6.
Rev Esp Enferm Dig ; 111(12): 973, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31696725

##### RESUMO

Hepatitis C virus infection has been associated with many dermatologic conditions such as lichen planus, porphyria cutanea tarda, and cryoglobulinemia. Recently, an association of HCV with systemic sclerosis has been reported. However, there are few reports of the association of localized scleroderma or morphea with Hepatitis C Virus infection. We describe the case of a 36 years old female patient suffering from prolonged morphea with difficult management, who was recently diagnosed of Hepatitis C Virus and received direct-acting antiviral agents treatment with Hepatitis C Virus clearance. Skin lesion faded away in a short period after successful therapy.

7.
Sci Eng Ethics ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31721023

##### RESUMO

One of the objectives in the field of artificial intelligence for some decades has been the development of artificial agents capable of coexisting in harmony with people and other systems. The computing research community has made efforts to design artificial agents capable of doing tasks the way people do, tasks requiring cognitive mechanisms such as planning, decision-making, and learning. The application domains of such software agents are evident nowadays. Humans are experiencing the inclusion of artificial agents in their environment as unmanned vehicles, intelligent houses, and humanoid robots capable of caring for people. In this context, research in the field of machine ethics has become more than a hot topic. Machine ethics focuses on developing ethical mechanisms for artificial agents to be capable of engaging in moral behavior. However, there are still crucial challenges in the development of truly Artificial Moral Agents. This paper aims to show the current status of Artificial Moral Agents by analyzing models proposed over the past two decades. As a result of this review, a taxonomy to classify Artificial Moral Agents according to the strategies and criteria used to deal with ethical problems is proposed. The presented review aims to illustrate (1) the complexity of designing and developing ethical mechanisms for this type of agent, and (2) that there is a long way to go (from a technological perspective) before this type of artificial agent can replace human judgment in difficult, surprising or ambiguous moral situations.

8.
Nat Commun ; 10(1): 5139, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723138

##### RESUMO

How and when tumoral clones start spreading to surrounding and distant tissues is currently unclear. Here we leveraged a model-based evolutionary framework to investigate the demographic and biogeographic history of a colorectal cancer. Our analyses strongly support an early monoclonal metastatic colonization, followed by a rapid population expansion at both primary and secondary sites. Moreover, we infer a hematogenous metastatic spread under positive selection, plus the return of some tumoral cells from the liver back to the colon lymph nodes. This study illustrates how sophisticated techniques typical of organismal evolution can provide a detailed, quantitative picture of the complex tumoral dynamics over time and space.

9.
Oncoimmunology ; 8(8): 1602460, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413912

##### RESUMO

Intravesical Bacille Calmette-Guérin (BCG) remains the most effective treatment for high-risk non-muscle-invasive bladder cancer (NMIBC), unfortunately there is no validated biomarker to predict clinical outcome. Here we tried to explore the possibility that a combination of the density of peritumoral infiltrating cells (Th1, Th2 and PD-L1) and the composition of peripheral immune cells (neutrophil and lymphocyte counts) could generate a more reliable prognostic biomarker. Twenty-two patients with high-risk NMIBC treated with BCG (10 BCG nonresponders and 12 BCG responders) were selected. BCG responders had significantly lower level of peritumoral T-bet+ cells with an associated higher GATA-3+/T-bet+ ratio (p = 0.04, p = 0.02, respectively). Furthermore, the immune polarization in tissue (GATA-3+/T-bet+ ratio) adjusted for the systemic inflammation (neutrophil-to-lymphocyte ratio) showed a significantly higher association with the BCG response (p = 0.004). A survival analysis demonstrated prolonged recurrence-free survival (RFS) in patients with a lower T-bet+/Lymphocyte ratio and higher GTR/NLR (p = 0.01). No association was observed between peritumoral PD-L1+ expression and the BCG response. In conclusion, alterations in overall immune function, both local and systemic, may influence the therapeutic response to BCG, therefore a combined analysis of tumoral (Th2/Th1 ratio) and peripheral (NLR) immune composition prior to treatment may be a promising approach to predict the BCG response in high-risk NMIBC patients.

10.
Prev Med Rep ; 15: 100915, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31297309

##### RESUMO

This systematic review and meta-analysis examined the literature on early care and education center (ECEC)-based physical activity interventions to identify ecologic environmental factors that improve cardiovascular fitness (CVF) in preschool-aged children. Data sources included PubMed, Web of Science, Cochrane Library Trials, CINHAL, Science Direct, PsychINFO and SPORTDiscus. Peer-reviewed publications of studies that met the following criteria were eligible for inclusion: (1) mean age of participants between two and a half and five and a half years old enrolled in a pre-primary school; (2) randomized controlled trials or quasi-experimental interventions with a control group; (3) interventions occurring before, during, or immediately after school; (4) use of an objective measure or field-based estimate of CVF; (5) enrolled apparently healthy children. In June of 2018, titles (nâ¯=â¯1197) were reviewed for inclusion into the study and 74 abstracts/full texts were assessed for eligibility. Ten articles met all eligibility criteria and were included in the final review. A random effects meta-analysis suggested a moderate-to-large effect size for ECEC-based interventions to increase CVF (gâ¯=â¯0.75; 95%CI [0.40-1.11]). Interventions that included three or more ecologic environments (gâ¯=â¯0.79 [0.34-1.25]) were more effective than interventions occurring at the individual level (gâ¯=â¯0.67 [0.12-1.22]). Study quality was moderate, and (meanâ¯±â¯SD) 17.9â¯±â¯4.3 (63.9%) of 28 checklist items were reported. Preliminary evidence suggests that ECEC-based interventions to increase CVF are highly effective at improving preschool children's exercise test scores. Although ECEC-based interventions show promise, the small number of studies included in this review limits confidence in these findings. Review registered at PROSPERO CRD42018099115.

11.
Rev Gastroenterol Peru ; 39(2): 193-196, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31333240

##### RESUMO

Mucormycosis is a rare, usually fatal, opportunistic infection that mostly affects people with immune deficiency or associated pathologies. There are few reports of this disease in patients without the traditional risk factors, still unknown what could be the real predisposing causes involved. The forms of presentation are rhinocerebral, cutaneous, pulmonary, gastrointestinal and disseminated. This is why, due to the difficult diagnosis, high mortality and uncommon presentation, we report the case of a 4-year-old child without immunodeficiency or background pathologies who developed an esophagogastric mucormycosis.

##### Assuntos
Mucormicose , Gastropatias/microbiologia , Pré-Escolar , Humanos , Imunocompetência , Masculino , Mucormicose/diagnóstico , Gastropatias/diagnóstico
12.
Hisp Health Care Int ; : 1540415319858075, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234651

##### RESUMO

INTRODUCTION: Middle-aged Hispanic women have the highest prevalence of overweight and lifetime risk for diabetes of all gender/racial groups. This study examines use of alternative medicine for weight loss and diabetes management among overweight and obese Mexican American women with or at risk for diabetes. METHOD: As part of a diabetes risk-reduction intervention targeting overweight and obese Hispanic women at a federally qualified health center in Hillsboro, Oregon, we administered a survey of different treatment modalities, including alternative medicine, traditional Mexican medicine, and home remedies to 85 Hispanic women. We also asked participants how often they disclosed their use of alternative methods to their providers. RESULTS: Nearly all participants with diabetes (97%) reported using at least one alternative strategy for diabetes control, with home remedies, commercial weight-loss products, and herbal teas being the most endorsed. Most participants with diabetes and half of those without diabetes reported never telling their provider. CONCLUSION: This group of women reported a high prevalence of use of alternative methods for weight control and diabetes management. Yet most participants with diabetes never reported this use to a health care provider. To ensure patient safety, providers treating Hispanic women need to probe for complementary and alternative medicine practices.

13.
Clin Infect Dis ; 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30958536

##### RESUMO

BACKGROUND: Diabetes mellitus (DM) increases the risk of active tuberculosis (TB) and worsens TB outcomes, putting TB control in jeopardy especially in TB endemic countries with rising DM prevalence rates. We assessed DM status and clinical correlates in TB patients across settings in Indonesia, Peru, Romania and South Africa. METHODS: Age-adjusted DM prevalence was estimated using laboratory glycated haemoglobin (HbA1c) or fasting plasma glucose (FPG) in TB patients. Detailed and standardized socio-demographic, anthropometric and clinical measurements were made. Characteristics of TB patients with or without DM were compared using multi-level mixed effect regression models with robust standard errors. RESULTS: Of 2185 TB patients (median 36.6 years, 61.2% male, 3.8% HIV-infected), 12.5% (267/2128) had DM, 1/3 of whom were newly diagnosed. Age-standardized DM prevalence ranged from 10.9% (South Africa) to 19.7% (Indonesia). Median HbA1c in TB-DM patients ranged from 7.4% (Romania) to 11.3% (Indonesia). Compared to those without DM, TB-DM patients were older with higher Body Mass Index (BMI) (p-value<0.05). Compared to those with newly diagnosed DM, TB patients previously known to have DM had higher BMI and HbA1c, less severe TB, and more frequent comorbidities, DM complications and hypertension (p-value<0.05). CONCLUSIONS: We show that DM prevalence and clinical characteristics of TB-DM vary considerably between countries. Diabetes is mostly known but untreated, hyperglycemia is often severe, and many patients with combined TB and DM have significant cardiovascular disease risk and severe TB, underlining the need to improve strategies for better clinical management of combined TB and DM.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31029365
15.
J Appl Oral Sci ; 27: e20180359, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30970114

##### RESUMO

Amelogenesis imperfecta (AI) is a group of enamel development disorders that alter the structure and chemical composition of the tissue. There is great variability in the clinical presentation; according to Witkop, AI can be categorized into 14 subtypes, which makes its diagnosis extremely complex. OBJECTIVE: This study aimed to describe and determine the frequency of clinical and radiographic features and inheritance patterns found in 41 Chilean families diagnosed with diverse types of AI. MATERIAL AND METHODS: We analyzed the clinical records, photographs, pedigrees and radiographs of 121 individuals recruited between 2003 and 2016. All of the information was included in a database that was analyzed using the application Stata 14. RESULTS: The 72 affected individuals had average age of 16 years, and no sex association with the presence of AI was found. The most frequent clinical subtypes were as follows: 43% hypomature, 25% hypoplastic, 21% hypomature/hypoplastic, 7% hypocalcified and 4% hypocalcified/hypoplastic. The number of severely affected teeth was 22, which occurred in the patients with hypocalcified and hypocalcified/hypoplasic AI who presented the highest number of damaged teeth. Caries and periodontal disease were found in 47 and 32% of the patients, respectively. Malocclusions were observed in 43% of the individuals with AI, with open bite being the most frequent. Radiographically, the thickness of the enamel decreased in 51% of the patients, and 80% showed decreased radiopacity of the enamel compared to that of dentin. Autosomal dominant inheritance pattern was found in 37% of the families with hypoplastic AI, and autosomal recessive pattern was present in 56% of the other clinical subtypes, but more frequently in those affected with hypomature and hypocalcified AI. CONCLUSION: Of the five clinical subtypes, autosomal recessive hypomature, autosomal dominant hypoplastic and autosomal recessive hypomature/hypoplastic AI were the most prevalent subtypes in this group.

##### Assuntos
Amelogênese Imperfeita/diagnóstico por imagem , Amelogênese Imperfeita/genética , Genealogia e Heráldica , Padrões de Herança , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Amelogênese Imperfeita/epidemiologia , Amelogênese Imperfeita/patologia , Criança , Pré-Escolar , Chile/epidemiologia , Esmalte Dentário/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Distribuição por Sexo , Estatísticas não Paramétricas , Adulto Jovem
16.
AIDS Care ; 31(12): 1509-1517, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30917676

##### RESUMO

Studies exploring gender differences in health-related quality of life (HRQOL) of people living with HIV/AIDS (PLWHA) are scarce and contradictory. This study evaluated gender differences in HRQOL of 744 PLWHA with median (IQR) age 44 (37-48) years and HIV infection diagnosed 12 (5-20) years earlier. Results showed important differences between genders (p < .05). Better male physical health was related to being employed, not having economic worries, not receiving psychological support, not having injected drugs in past, low negative mood HIV-related, low HIV illness representation and internalized stigma, and high body image satisfaction and health behavior. For women, variables were fewer years since HIV diagnosis and low enacted stigma-personal experience of rejection. Mentally, variables in men were being employed, not having injected drugs, having a stable partner, high health behavior, use of problem-solving coping, personal autonomy and personal meaning. In women, better mental health was related to high CD4 cells, self-esteem and body image satisfaction, and negative mood HIV-related. Men and women coincided in absence of past opportunistic infections being related to better physical and mental health, and absence of side effects for physical health and low HIV-related stress and HIV illness representation for mental health. Our results highlight the need for detailed study of gender differences that identify the bio-psycho-socio inequalities that affect HRQOL.

17.
Opt Express ; 27(4): 4317-4328, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876048

##### RESUMO

18.
J Racial Ethn Health Disparities ; 6(4): 799-805, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30859515

##### RESUMO

BACKGROUND: Overweight Hispanic women are at high risk for type 2 diabetes. A clinical diagnosis of hyperglycemia is often necessary to access interventions. We examined the prevalence of undiagnosed hyperglycemia among a group of low-income overweight or obese Hispanic women, who were receiving care at a Federally Qualified Health Center (FQHC). METHODS: Among 196 overweight or obese Hispanic women (mean age 44 ± 10 years, mean weight 86.8 ± 16.5 kg, mean body mass index [BMI] 36.5 ± 6.4 kg/m2) enrolled in a randomized clinical weight-loss trial, we compared A1C and fasting blood glucose (FBG) obtained at baseline with women's existing diabetes and prediabetes diagnoses in the medical record. RESULTS: According to the information in participants' medical records, 36% (70/196) had diagnosed diabetes, 20% (39/196) had a diagnosis of prediabetes, and the remaining 44% (87/196) had neither diagnosis. Among participants without a diagnosis of diabetes or prediabetes during the baseline screening for our study, 63% (55/87) had at least one test in the prediabetes range (baseline A1C and FBG were in prediabetes range for 39 and 55 participants, respectively), and 13% (11/87) had at least one test in the diabetic range (baseline A1C and FBG values in diabetes range for 3 and 11 participants, respectively). DISCUSSION: We found substantial prevalence of undiagnosed hyperglycemia among a sample of overweight and obese Hispanic women. It is possible that limited awareness of diabetes risk may be a barrier to patient compliance with screening recommendations.

19.
J Chromatogr A ; 1594: 93-104, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30792043

##### RESUMO

The effectiveness of highly polar pesticides in agriculture is well known, while their low costs contribute to the frequent use. On the other hand, their physicochemical properties make their analytical determination a challenging task. The aim of this study is the evaluation of a methanol-based extraction method with a simple clean-up step using a selective multiresidue LC-MS/MS method for 14 highly polar pesticides and their metabolites. For the clean-up step, several sorbents from different brands, with diverse mechanisms of action, were tested. Different dilution factors for the final extract were also evaluated in order to check the impact on the matrix effects. The optimised method was validated for matrices from different commodity groups. Recovery studies performed with grapes, lettuce, orange, oat and soya beans showed absolute average recoveries in the range 70-120% with relative standard deviation values below 20% for almost all the pesticides tested. The matrix effects observed were very different in each matrix and for each individual pesticide evaluated. Therefore, isotopically labeled procedural internal standards were used for all compounds in order to correct for recovery and matrix effects. Method Limits of Quantification for most analyte-matrix combinations were 0.02 or 0.05 mg kg-1. The final optimised method appeared to be reproducible and robust in routine analysis of a wide variety of fruits, vegetables and cereals. Monitoring results are presented to show the occurrence of the compounds studied in real samples. The residue concentrations ranged from 0.023 to 30 mg kg-1 for the analytes detected.

##### Assuntos
Cromatografia Líquida , Análise de Alimentos/métodos , Praguicidas/análise , Espectrometria de Massas em Tandem , Grão Comestível/química , Análise de Alimentos/normas , Frutas/química , Interações Hidrofóbicas e Hidrofílicas , Metanol/química , Resíduos de Praguicidas/análise , Reprodutibilidade dos Testes , Verduras/química
20.
Rev. esp. enferm. dig ; 111(2): 129-133, feb. 2019. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-182195