Horizontally and vertically sensitive schlieren and shadowgraph system.

Visualizing and quantifying certain variables are essential in fluid flow studies. If we add that these tasks should be achieved in great detail, it would be beneficial to implement optical techniques that would reveal these characteristics. Based on this premise, we present a z-schlieren setup that allows simultaneous recording of horizontal and vertical sensitivity schlieren images and shadowgraph images. These two visualization techniques complement each other since each method has its own strengths and weaknesses. The optical system employs two ultra-thin filters, an RGB light-emitting diode (LED), and a color digital camera. As a result, the data obtained are significantly improved over the existing standard schlieren methods. Furthermore, the fluid flow is better analyzed by combining the schlieren and shadowgraph techniques since a straightforward optical system gathers helpful information. The performance of the optical system is demonstrated by visualizing the convective fluid flow of a candle flame and measuring the temperature fields of the flow of a heated rectangular plate.

Minimization of measuring points for the electric field exposure map generation in indoor environments by means of Kriging interpolation and selective sampling.

In a world with increasing systems accessing to radio spectrum, the concern for exposure to electromagnetic fields is growing and therefore it is necessary to check limits in those areas where electromagnetic sources are working. Therefore, radio and exposure maps are continuously being generated, mainly in outdoor areas, by using many interpolation techniques. In this work, Surfer software and Kriging interpolation have been used for the first time to generate an indoor exposure map. A regular measuring mesh has been generated. Elimination of Less Significant Points (ELSP) and Geometrical Elimination of Neighbors (GEN) strategies to reduce the measuring points have been presented and evaluated. Both strategies have been compared to the map generated with all the measurements by calculating the root mean square and mean absolute errors. Results indicate that ELSP method can reduce up to 70% of the mesh measuring points while producing similar exposure maps to the one generated with all the measuring points. GEN, however, produces distorted maps and much higher error indicators even for 50% of eliminated measuring points. As a conclusion, a procedure for reducing the measuring points to generate radio and exposure maps is proposed based on the ELSP method and the Kriging interpolation.

Temperature Measurement of Fluid Flows by Using a Focusing Schlieren Method.

A method for measuring planar temperature fields of fluid flows is proposed. The focusing schlieren technique together with a calibration procedure to fulfill such a purpose is used. The focusing schlieren technique uses an off-axis circular illumination to reduce the depth of focus of the optical system. The calibration procedure is based on the relation of the intensity level of each pixel of a focused schlieren image to the corresponding cutoff grid position measured at the exit focal plane of the schlieren lens. The method is applied to measure planar temperature fields of the hot air issuing from a 10 mm diameter nozzle of a commercial Hot Air Gun Soldering Station Welding. Our tests are carried out at different temperature values and different planes along the radial position of the nozzle of the hot air. The experimental values of temperature measurements are in agree with those measured using a thermocouple.

Wide-range average temperature measurements of convective fluid flows by using a schlieren system.

In the schlieren method, the deflection of light by the presence of an inhomogeneous medium is proportional to the gradient of its refractive index. In the presence of temperature variations in a fluid flow, the refraction index is related to the gas density by the Gladstone-Dale constant, which depends on the nature of the gas and the wavelength of light propagating in the medium. The deflection of light in a schlieren system is represented by intensity variations on the observation plane. Then, for a digital camera, the intensity level registered in each pixel depends mainly on the refractive index variation of the medium and exposure time. Therefore, if we regulate the intensity value of each pixel by controlling the exposure time, it is possible to adjust the temperature value measurements. In this way, a specific exposure time of a digital camera allows us to measure a determined range of temperature values. For that reason, in this study we determine the range of temperatures that can be measured with a digital camera for different exposure times. By doing this, a wide range of average temperature value fields can be obtained by summing up the temperature contribution of each exposure time. The basic idea in our approach to measure temperature by using a schlieren system is to relate the intensity level of each pixel in a schlieren image to the corresponding knife-edge position measured at the exit focal plane of the system. Our approach is applied to the measurement of temperature fields of the air convection caused by a heated rectangular metal plate (7.3 cm×12 cm) and a candle flame. We found that the maximum temperature values obtained for exposure times of 31.3, 15.7, 7.9, 3.9, and 2 ms were 67.3°C, 122.6°C, 217.4°C, 364.3°C, and 524.0°C, respectively.

Predictability of short implants ( < 10 mm) as a treatment option for the rehabilitation of atrophic maxillae. A systematic review.

BACKGROUND: Short implants (< 10 mm) are one of the treatment options available in cases of limited vertical bone. Although such implants are now widely used, there is controversy regarding their clinical reliability. The purpose of this paper is to evaluate the predictability of short implants as an alternative to technically more complex treatments in patients with atrophic maxillae, based on a systematic review of the literature and the analysis of the implant survival rates, changes in peri-implant bone level, and associated complications. It is postulated that short implants offer clinical results similar to those of longer implants. MATERIAL AND METHODS: A Medline-PubMed search was made covering the period between January 2004 and December 2014 (both included). Studies in English published in indexed journals, involving at least 20 implants and with a follow-up period of at least 12 months were considered. A manual search in four high impact journals was also conducted. RESULTS: A total of 37 studies meeting the inclusion criteria were included in this review. 9792 implants placed in over 5000 patients were analyzed. CONCLUSIONS: Based on the results of this review, short implants are seen to offer clinical results in terms of survival, bone loss and complications similar to those of longer implants.

Measurement of temperature and velocity fields in a convective fluid flow in air using schlieren images.

A convective fluid flow in air could be regulated if the physical process were better understood. Temperature and velocity measurements are required in order to obtain a proper characterization of a convective fluid flow. In this study, we show that a classical schlieren system can be used for simultaneous measurements of temperature and velocity in a convective fluid flow in air. The schlieren technique allows measurement of the average fluid temperature and velocity integrated in the direction of the test beam. Therefore, in our experiments we considered surfaces with isothermal conditions. Temperature measurements are made by relating the intensity level of each pixel in a schlieren image to the corresponding knife-edge position measured at the exit focal plane of the schlieren system. The same schlieren images were also used to measure the velocity of the fluid flow by using optical flow techniques. The algorithm implemented analyzes motion between consecutive schlieren frames to obtain a tracked sequence and finally velocity fields. The proposed technique was applied to measure the temperature and velocity fields in natural convection of air due to unconfined and confined heated rectangular plates.

A multicenter randomized open-label clinical trial for convalescent plasma in patients hospitalized with COVID-19 pneumonia.

BACKGROUNDPassive immunotherapy with convalescent plasma (CP) is a potential treatment for COVID-19. Evidence from controlled clinical trials is inconclusive.METHODSWe conducted a randomized, open-label, controlled clinical trial at 27 hospitals in Spain. Patients had to be admitted for COVID-19 pneumonia within 7 days from symptom onset and not on mechanical ventilation or high-flow oxygen devices. Patients were randomized 1:1 to treatment with CP in addition to standard of care (SOC) or to the control arm receiving only SOC. The primary endpoint was the proportion of patients in categories 5 (noninvasive ventilation or high-flow oxygen), 6 (invasive mechanical ventilation or extracorporeal membrane oxygenation [ECMO]), or 7 (death) at 14 days. Primary analysis was performed in the intention-to-treat population.RESULTSBetween April 4, 2020, and February 5, 2021, 350 patients were randomly assigned to either CP (n = 179) or SOC (n = 171). At 14 days, proportion of patients in categories 5, 6, or 7 was 11.7% in the CP group versus 16.4% in the control group (P = 0.205). The difference was greater at 28 days, with 8.4% of patients in categories 5-7 in the CP group versus 17.0% in the control group (P = 0.021). The difference in overall survival did not reach statistical significance (HR 0.46, 95% CI 0.19-1.14, log-rank P = 0.087).CONCLUSIONCP showed a significant benefit in preventing progression to noninvasive ventilation or high-flow oxygen, invasive mechanical ventilation or ECMO, or death at 28 days. The effect on the predefined primary endpoint at 14 days and the effect on overall survival were not statistically significant.TRIAL REGISTRATIONClinicaltrials.gov, NCT04345523.FUNDINGGovernment of Spain, Instituto de Salud Carlos III.

A clinical longitudinal study 323 porcelain laminate veneers. Period of study from 3 to 11 years.

OBJECTIVE: The objective of this study was to evaluate the clinical results of 323 porcelain laminate veneers over a period of 3 to 11 years. MATERIAL AND METHOD: This study included 70 patients, aged between 18 and 74 years. Of the 323 total veneers, 124 were of a simple design and 199 were of a functional design. The condition of the soft tissues and hygiene, in addition to the condition of the abutment teeth, the restorations and patient satisfaction were all clinically examined. In carrying out the statistical analysis, a descriptive approach was taken in analyzing the data. The Kaplan Meier method was used for statistically analyzing the survival rates of the porcelain laminate veneers. RESULTS: Analysis of the soft tissue revealed marginal recession in 7.7% of the cases, and in 21.6% of the cases, bleeding was detected on probing. Analysis of the condition of the abutment teeth revealed secondary caries and hypersensitivity in 3.1% of the cases, and changes in pulp vitality were observed in 2.8% of the cases. In studying the condition of the restorations, marginal integrity was observed to be excellent in 98% of the cases, slight marginal pigmentation was present in 39.3% of the cases, fractures were present in 4% of the cases and decementation in 9% of the cases. The degree of patient satisfaction was considered to be excellent in 97.1% of the cases. CONCLUSIONS: Porcelain laminate veneers are a predicable treatment option that offer excellent results.

Inhibition of α-amylase by flavonoids: Structure activity relationship (SAR).

Flavonoids are recognized to regulate animals' food digestion processes trough interaction with digestive enzymes. The binding capacity of hesperetin (HES), luteolin (LUT), quercetin (QUE), catechin (CAT) and rutin (RUT) with pancreatic α-amylase were evaluated, using UV-Vis spectroscopy, fluorescence and molecular docking. Using p-nitrophenyl-α-d-maltopentoside (pNPG5) as substrate analog, LUT showed the best inhibitory capacity, even better than that of the positive control, acarbose (ACA). A mixed-type inhibition was observed for HES, LUT and QUE, a competitive-type for ACA, while no inhibition was observed with CAT and RUT. In agreement with kinetic results, α-amylase presented a higher affinity for LUT, when analyzed by fluorescence quenching. The binding of flavonoids to amylase followed a static mechanism, where the binding of one flavonoid per enzyme molecule was observed. Docking analysis showed that flavonoids bound near to enzyme active site, while ACA bound in another site behind the catalytic triad. Extrinsic fluorescence analysis, together with docking analysis pointed out that hydrophobic interactions regulated the flavonoid-α-amylase interactions. The present study provides evidence to understand the relationship of flavonoids structure with their inhibition mechanism.

[Candida spp. in the gut microbiota of people with autism: a systematic review]. / Candida spp. en la microbiota intestinal de las personas con autismo: revision sistematica.

INTRODUCTION: There is great interest in studies on the implications that gut microbiota exerts on the behavior of people with autism spectrum disorders (ASD), through the microbiota-gut-brain axis. Most studies on microbiota are focused on the possible involvement of bacteria on people with ASD, but few of them are focussed on the effect of microorganisms in the Fungi kingdom. SUBJECTS AND METHODS: The present study performs a systematic review of the presence of Candida spp. in people with ASD using the PRISMA method. RESULTS: A total of three articles were found after applying the exclusion and inclusion criteria of the systematic review. Two studies coincided in reporting significant differences in the increase in the frequency of the Candida spp. genus in people with ASD. while the third study did not report significant differences of Candida spp. genus between people with ASD. CONCLUSIONS: Although there is a clear lack of investigation of both the Candida ssp. genus and the whole Fungi kingdom in people with ASD, the studies point to an important presence of this genre in this group. Specifically, in the results found in this review, the highest prevalence of the C. albicans in children with ASD stands out. However, little is still known about the involvement of Candida spp., and other types of fungi, on gastrointestinal symptoms and ASD symptoms, in children with ASD.

TITLE: Candida spp. en la microbiota intestinal de las personas con autismo: revision sistematica.Introduccion. Existe gran interes en los estudios sobre las implicaciones que la microbiota intestinal ejerce en el comportamiento de personas con trastornos del espectro autista (TEA) a traves del eje microbiota-intestino-cerebro. La mayoria de los estudios sobre microbiota estan enfocados en la posible implicacion de las bacterias sobre personas con TEA, pero pocos versan sobre el efecto de los microorganismos del reino Fungi. Sujetos y metodos. Se realiza una revision sistematica mediante el protocolo PRISMA de la presencia de Candida spp. en las personas con TEA. Resultados. Se encontro un total de tres articulos tras aplicar los criterios de exclusion e inclusion de la revision sistematica. Dos estudios coincidieron en mostrar diferencias significativas en el aumento de la frecuencia del genero Candida spp. en personas con TEA, mientras que en otro no se hallaron diferencias. Conclusiones. Pese a que existe una clara falta de investigacion tanto del genero Candida ssp. como de todo el reino Fungi en las personas con TEA, los estudios apuntan a una importante presencia de dicho genero en este colectivo. Concretamente, en los resultados encontrados se destaca la mayor prevalencia del genero C. albicans en los niños con TEA. Sin embargo, aun se sabe poco sobre la implicacion de Candida spp. y otros tipos de hongos sobre los sintomas gastrointestinales y la sintomatologia del autismo en niños con TEA.

Validation of the Repetitive Behavior Scale-Revised in Spanish-Speakers Participants with Autism Spectrum Disorder.

Restricted and repetitive behavior (RRB) is one of the two key diagnostic features of autism spectrum disorder (ASD). DSM-5 highlights the importance of severity-based diagnostic modifiers assigned on the basis of intensity of needed supports. Therefore, there is a need for available measures that assess the severity of RRB. The repetitive behavior scale-revised (RBS-R) is probably the most used informant-based rating scale for the assessment of RRB and interests observed in ASD. The present study examined the psychometric properties of the Spanish version of the RBS-R in a sample of 233 participants with ASD, aged 3 to 63 years. Results revealed a six-factor model, good internal consistency, and concurrent-divergent validity. These findings suggest the utility of the Spanish version of RBS-R.

A three-dimensional computational analysis of magnetic resonance images characterizes the biological aggressiveness in malignant brain tumours.

Glioblastoma (GBM) is the most frequent and aggressive type of primary brain tumour. The development of image-based biomarkers from magnetic resonance images (MRIs) has been a topic of recent interest. GBMs on pre-treatment post-contrast T1-weighted (w) MRIs often appear as rim-shaped regions. In this research, we wanted to define rim-shape complexity (RSC) descriptors and study their value as indicators of the tumour's biological aggressiveness. We constructed a set of widths characterizing the rim-shaped contrast-enhancing areas in T1w MRIs, defined measures of the RSC and computed them for 311 GBM patients. Survival analysis, correlations and sensitivity studies were performed to assess the prognostic value of the measurements. All measures obtained from the histograms were found to depend on the class width to some extent. Several measures (FWHM and ßR) had high prognostic value. Some histogram-independent measures were predictors of survival: maximum rim width, mean rim width and spherically averaged rim width. The later quantity allowed patients to be classified into subgroups with different rates of survival (mean difference 6.28 months, p = 0.006). In conclusion, some of the morphological quantifiers obtained from pre-treatment T1w MRIs provided information on the biological aggressiveness of GBMs. The results can be used to define prognostic measurements of clinical applicability.

Predictive and prognostic potential of volume-based metabolic variables obtained by a baseline 18F-FDG PET/CT in breast cancer with neoadjuvant chemotherapy indication. / Papel predictivo y pronóstico de las variables volumétricas metabólicas obtenidas en la 18F-FDG PET/TC en el cáncer de mama con indicación de quimioterapia neoadyuvante.

AIM: To investigate the usefulness of metabolic variables using 18F-FDG PET/CT in the prediction of neoadjuvant chemotherapy (NC) response and the prognosis in locally advanced breast cancer (LABC). MATERIAL AND METHODS: Prospective study including 67 patients with LABC, NC indication and a baseline 18F-FDG PET/CT. After breast tumor segmentation, SUV variables (SUVmax, SUVmean and SUVpeak) and volume-based variables, such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG), were obtained. Tumors were grouped into molecular phenotypes, and classified as responders or non-responders after completion of NC. Disease-free status (DFs), disease-free survival (DFS), and overall survival (OS) were assessed. A univariate and multivariate analysis was performed to study the potential of all variables to predict DFs, DFS, and OS. RESULTS: Fourteen patients were classified as responders. Median±SD of DFS and OS was 43±15 and 46±13 months, respectively. SUV and TLG showed a significant correlation (p<0.005) with the histological response, with higher values in responders compared to non-responders. MTV and TLG showed a significant association with DFs (p=0.015 and p=0.038 respectively). Median, mean and SD of MTV and TLG for patients with DFs were: 8.90, 13.73, 15.10 and 33.78, and 90.54 and 144.64, respectively. Median, mean and SD of MTV and TLG for patients with non-DFs were: 16.72, 29.70 and 31.09 and 90.89, 210.98 and 382.80, respectively. No significant relationships were observed with SUV variables and DFs. Volume-based variables were significantly associated with OS and DFS, although in multivariate analysis only MTV was related to OS. No SUV variables showed an association with the prognosis. CONCLUSION: Volume-based metabolic variables obtained with 18F-FDG PET/CT, unlike SUV based variables, were good predictors of both neoadjuvant chemotherapy response and prognosis.

Participation of epidemiologists and/or biostatisticians and methodological quality of published controlled clinical trials.

STUDY OBJECTIVE: This study assessed several methodological aspects related to the quality of published controlled clinical trials (CCTs) in relation to the participation of an epidemiologist/biostatistician (E/B). DESIGN: Handsearch of CCTs published in four medical leading journals for 1993-1995. METHODS: Quality variables, abstracted from a review, were related to authors' specialties. Five hundred and ninety four CCTs were identified via a hand search. The department/unit membership was used to attribute authors' specialties. Of 594 CCTs identified, in 127 the authors' specialties could not be known, leaving 467 trials for analysis. RESULTS: E/B participation occurred in 178 trials (38.1%). This participation was more frequent in multicentric, bigger, and in those trials describing any funding agency. These factors were controlled for in the analysis. E/B participation was positively associated with pre-study sample size estimation (OR = 1.5, 95% confidence intervals (CI) 1.0, 2.3), with reporting the dates for starting/ending the study (OR = 2.1, 95% CI 1.4, 3.3), with using an objectively assessed outcome (OR = 2.4, 95% CI 1.2, 4.6) and with the intention to treat principle (OR = 2.0, 95% CI 1.3, 3.0). The overall quality score was higher in trials where E/B participated. CONCLUSIONS: The results suggest that E/B improve the quality (at least of reports) of clinical trials. Given that quality of research is frequently used to evaluate potential sources of heterogeneity between trials, these results are relevant for meta-analysis.

Response of three types of cast posts and cores to static loading.

OBJECTIVE: An analysis is made of the influence of continuous compression loading on different types of cast posts and cores and its effects on the crowns and teeth. METHOD AND MATERIALS: Thirty extracted maxillary canines were prepared and divided into three groups (n = 10) according to the type of cast posts and cores used for restoration: chrome-nickel alloy, acetalic resin, and IPS-Empress porcelain. Metallic cast crowns were luted onto the cores. The specimens were evaluated with an Instron testing machine at an angulation of 45 degrees and a forward speed of 0.5 mm/min. After testing, the specimens were sectioned along the axis and examined under x40 magnification. RESULTS: Mean load resistance of the restorations until fracture was 2,120 N, 1,491 N, and 2,139 N in the chrome-nickel, IPS-Empress ceramic, and acetalic resin groups, respectively. CONCLUSION: Significant differences in resistance were observed between metal and porcelain and between resin and porcelain. Microscopically, the apical portion was found to be most affected by fracture and compromised the teeth subjected to chrome-nickel restorations. The metal cast posts and cores exhibited different angulations, while the ceramic restorations showed cracks. The acetalic resin cast posts and cores presented no fractures.