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Temperature is one of the most relevant physical quantities that affects almost all processes in nature. However, the realization of accurate temperature standards using current temperature references, like the triple point of water, is difficult due to the requirements on material purity and stability of the environment. In addition, in harsh environments, current temperature sensors with electrical readout, like platinum resistors, are difficult to implement, urging the development of optical temperature sensors. In 2018, the European consortium Photoquant, consisting of metrological institutes and academic partners, started investigating new temperature standards for self-calibrated, embedded optomechanical sensor applications, as well as optimised high resolution and high reliability photonic sensors, to measure temperature at the nano and meso-scales and as a possible replacement for the standard platinum resistant thermometers. This article presents an overview of the results obtained with sensor prototypes that exploit photonic and optomechanical techniques for sensing temperatures over a large temperature range (5 K to 300 K). Different concepts are demonstrated, including ring resonators, ladder-like resonators and suspended membrane optomechanical thermometers, highlighting initial performance and challenges, like self-heating that need to be overcome to realize photonic and optomechanical thermometry applications.

Objective We examined associations among serial measures of linear growth and relative weight with adult body composition.Design Secondary data analysis of prospective birth cohort studies.Settings Six birth cohorts from Brazil, Guatemala, India, the Philippines and South Africa.Participants 4173 individuals followed from birth to ages 22–46 years with complete and valid weight and height at birth, infancy, childhood and adolescence, and body composition in adult life.Exposures Birth weight and conditional size (standardised residuals of height representing linear growth and of relative weight representing weight increments independent of linear size) in infancy, childhood and adolescence.Primary outcome measures Body mass index, fat mass index (FMI), fat-free mass index (FFMI), fat mass/fat-free mass ratio (FM/FFM), and waist circumference in young and mid-adulthood.Results In pooled analyses, a higher birth weight and relative weight gains in infancy, childhood and adolescence were positively associated with all adult outcomes. Relative weight gains in childhood and adolescence were the strongest predictors of adult body composition (β (95% CI) among men: FMI (childhood: 0.41 (0.26 to 0.55); adolescence: 0.39 (0.27 to 0.50)), FFMI (childhood: 0.50 (0.34 to 0.66); adolescence: 0.43 (0.32 to 0.55)), FM/FFM (childhood: 0.31 (0.16 to 0.47); adolescence: 0.31 (0.19 to 0.43))). Among women, similar patterns were observed, but, effect sizes in adolescence were slightly stronger than in childhood. Conditional height in infancy was positively associated with FMI (men: 0.08 (0.03 to 0.14); women: 0.11 (0.07 to 0.16)). Conditional height in childhood was positively but weakly associated with women’s adiposity. Site-specific and sex-stratified analyses showed consistency in the direction of estimates, although there were differences in their magnitude.Conclusions Prenatal and postnatal relative weight gains were positive predictors of larger body size and increased adiposity in adulthood. A faster linear growth in infancy was a significant but weak predictor of higher adult adiposity.

Category: Trauma; Ankle Introduction/Purpose: The anterior distal tibial tubercle (Tillaux-Chaput tubercle) frequently fractures in the wake of malleolar fractures. It provides attachment to the anterior tibiofibular syndesmosis and may be considered a fourth or anterior malleolus (AM). In analogy to posterior malleolar fractures, AM fractures may extend into the tibial incisura and tibial plafond. We analyzed the pathoanatomy of AM fractures and associated injuries in ankle fractures in adults. Methods: Over a course of 9 years, 140 patients (average age 58.3 years) with 140 acute malleolar fractures (OTA/AO 44) involving the anterolateral distal tibial rim were analyzed with CT imaging. All components of the malleolar fractures were analyzed and classified. Fracture patterns were compared with those of all 1,379 patients treated for malleolar fractures at our institution during the same 9-year period. Patients with fractures of the tibial pilon (OTA/AO 43) and patients aged less than 18 years were excluded as the frequent anterolateral distal tibial fractures along the physeal growth plate in adolescents are beyond the scope of this analysis. Fractures were classified according to the most frequent patterns and possible treatment options. Results: Of the 140 AM fractures, 52.9% were classified type 1 (extra-articular avulsion), 35.7% type 2 (incisura and plafond involvement), and 11.4% type 3 (impaction of the anterolateral plafond). The fibula was fractured in 87.1%, the medial malleolus in 67.1%, and the posterior malleolus in 69.3%. Isolated AM fractures were seen in only 6 cases (4.3%). The severity of AM fractures correlated negatively with that of posterior malleolar fractures (p

In recent decades, reports of deforestation, mass extinctions, biodiversity loss, and emergencies like floods and droughts have clearly highlighted the impact of human activities on climate change. This underscores the need for significant lifestyle changes to mitigate this impact. Pro-environmental behavior (PEB) change involves adopting actions that protect the environment and reducing environmentally harmful activities to promote sustainability. While qualitative research may provide unique insights into PEB barriers that are challenging to capture through quantitative methods, reports of qualitative studies are scattered across different literatures with little integration. With the present review, we bring together qualitative studies on PEB barriers and examine whether those studies reveal barriers compatible with existing barrier frameworks from environmental psychology. We identified 38 qualitative studies on barriers to PEB change. Our analysis revealed that most of the barriers to individual pro-environmental action identified in qualitative studies align with environmental psychology frameworks. These barriers were experienced not only by individuals in their role as consumer or citizen, but also by community-level actors (e.g., seeking to implement pro-environmental policies) and industrial decision-makers (e.g., aiming to reduce the ecological footprint of their business activities). Our findings underscore the multifaceted nature of barriers to PEB change and emphasize the importance of addressing structural and institutional factors alongside individual-level interventions. [ABSTRACT FROM AUTHOR]

Abstract Background and Aims Metabolic conditions such as obesity, type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease (NAFLD) are highly prevalent in Guatemala and increase the risk for a number of disorders, including hepatocellular carcinoma (HCC). Aflatoxin B1 (AFB1) levels are also notably elevated in the population and are known to be associated with HCC risk. Whether AFB1 also contributes to the high prevalence of the metabolic disorders has not been previously examined. Therefore, the purpose of this study was to assess the association between AFB1 and the metabolic conditions. Methods Four‐hundred twenty‐three individuals were included in the study, in which AFB1‐albumin adduct levels were measured in sera. Metabolic conditions included diabetes, obesity, central obesity, metabolic syndrome, and NAFLD. Crude and adjusted prevalence odds ratios (PORs) and 95% confidence intervals (95% CI) were estimated for the associations between the metabolic conditions and AFB1‐albumin adduct levels categorized into quartiles. Results The study found a significant association between AFB1‐albumin adduct levels and diabetes (Q4 vs Q1 POR = 3.74, 95%CI: 1.71‐8.19; P‐trend .003). No associations were observed between AFB1‐albumin adduct levels and the other conditions. Conclusions As diabetes is the metabolic condition most consistently linked to HCC, the possible association between AFB1 exposure and diabetes may be of public health importance. Further studies are warranted to replicate the findings and examine potential mechanisms.

Category: Ankle; Trauma Introduction/Purpose: Over the last decade, much attention has been paid to the fractures of the posterior malleolus as it became obvious that the mere presence of a posterior tibial fragment is associated with a less favorable prognosis in malleolar fractures. It seems logical to pay the anterior restraints of the ankle joint a similar attention as to the posterior ones. The anteriolateral distal tibia may be considered a 'fourth' or anterior malleolus. Here, we present a technique of fixation of trimalleolar fractures with additional fracture of the anterior tibial tubercle ('quadrimalleolar') or anterior fibular rim ('quadrimalleolar equivalent'). Methods: Twenty-four patients with a mean age of 60 years were treated with open reduction and internal fixation of all 4 malleoli. There were 17 quadrimalleolar and 6 quadrimalleolar equivalent fractures. One patient had both anterior tibial and fibular avulsion fractures in addition to a trimalleolar ankle fracture. Surgical approaches and internal fixation were tailored individually. Twenty patients were operated in prone position with direct fixation of the posterior malleolus and 4 patients in supine position with indirect anterior to posterior screw fixation of the posterior malleolus under transfibular control of reduction. Results: After fixation of al 4 malleoli, only one patient (4%) required a syndesmotic screw for residual syndesmotic instability on intraoperative testing. There were no infections, and no wound healing problems. All patients went on to solid union. No late fusions were needed. Nineteen patients (79%) could be reevaluated after a mean of 77 months (range, 15 to 156 months) follow- up. The Foot Function Index averaged 15 (range, 50 to 0), the Olerud and Molander Score averaged 79 (range, 45 to 100) and the AOFAS Ankle and Hindfoot Scale averaged 87 (range, 39 to 100). Conclusion: Fixation of the anterior and posterior tibial fragments increases syndesmotic stability by providing a bone-to-bone fixation. Reduction of displaced anterior and posterior tibial rim fractures restores the physiological shape of the tibial incisura and therefore facilitates fibular reduction. In the majority of cases, this also restores articular congruity of the lateral tibial plafond. Anatomic reduction of the anterior and posterior malleolus in addition to medial and lateral malleolar fixation leads to favourable functional results despite a complex (quadrimalleolar) fracture pattern.

Conventional spectroscopic ellipsometry is a powerful tool in optical metrology. However, when it comes to the characterization of non-periodic nanostructures or structured fields that are much smaller than the illumination spot size, it is not well suited as it integrates the results over the whole illuminated area. Instead, imaging ellipsometry can be applied. Especially imaging Mueller matrix ellipsometry is highly useful in nanostructure characterization and defect inspection, as it is capable to measure the complete Mueller matrix for each pixel in a microscope image of the sample. It has been shown that these so-called Mueller matrix images can help to distinguish geometrical features of nanostructures in the sub-wavelength regime due to visible differences in off-diagonal matrix elements. To further investigate the sensitivity of imaging Mueller matrix ellipsometry for sub-wavelength sized features, we designed and fabricated a sample containing geometrical nanostructures with lateral dimensions ranging from 50 to 5,000 nm. The structures consist of square and circular shapes with varying sizes and corner rounding. For the characterization of their Mueller matrix images, we constructed an in-house Mueller matrix microscope capable of measuring the full Mueller matrix for each pixel of a CCD camera, using an imaging system and a dual-rotating compensator configuration for the ellipsometric system. The samples are illuminated at 455 nm wavelength and the measurements can be performed in both transmission and reflection. Using this setup, we systematically examine the sensitivity of Mueller matrix images to small features of the designed nanostructures. Within this contribution, the results are compared with traceable atomic force microscopy measurements and the suitability of this measurement technique in optical nanometrology is discussed. AFM measurements confirm that the fabricated samples closely match their design and are suitable for nanometrological test measurements. Mueller matrix images of the structures show close resemblance to numerical simulations and significant influence of sub-wavelength features to off-diagonal matrix elements.

Introduction: Childhood obesity is a principal concern worldwide. Guatemalan households have the highest prevalence of double burden of malnutrition in the world. These households are self-identified as indigenous and live with lower incomes in rural communities. However, there are limited data on risk factors for childhood obesity and limited information regarding the school environments, especially in rural communities. The objectives of this study were to determine the prevalence of overweight and obesity in a sample of rural schoolchildren, evaluate whether there is significant variability across schools, and characterize the food environment around public elementary schools in rural communities. Methods: A cross-sectional study was conducted in four rural public schools within three villages of El Progreso, a Department (state) of Guatemala, located about 60 km east of Guatemala City. Anthropometric measures and sociodemographic information for 398 schoolchildren and their mothers were collected in 2018. Environmental audits of food outlets and food advertisements were completed for a 250- and 500-meter radius around schools. Food outlets and food advertisements were categorized as healthy and less healthy, or acceptable or not acceptable, respectively, using international protocols. One-way ANOVA was used to compare schools and continuous demographic variables. Fisher’s LSD post hoc test was used to examine differences between schools. Chi-Squared tests were conducted to evaluate differences between categorical demographic variables, overweight and obesity, and variables regarding food environments. A logistic regression was used to examine factors associated with overweight and obesity and variability across schools, adjusted for household income, child sex and age, and maternal education and age. Results: The overall percentage of overweight and obesity among schoolchildren across all four schools was 32.4%. There was a higher percentage of less healthful food outlets compared to healthful food outlets and overall food outlets within

Interferometric experiments are often limited in sensitivity by the thermal noise of the mirrors. In particular, interferometric gravitational wave detectors and laser stabilization resonators can benefit from reduced mirror noise. We present results of experimental investigations on micro-structured mirrors (meta-mirrors) and hybrid etalon mirrors (meta-etalons) promising particularly low thermal noise. We show the first characterization of meta-etalons scattering and absorption losses, demonstrating optical losses below 500 ppm. This level of optical losses is sufficient for planning direct thermal noise measurement in dedicated optical cavity experiments. These measurements would be very important for validating the thermal noise predictions. We present our development toward the integration of meta-etalons in ultra-stable optical cavities.

In order to accomplish more functional and efficient light routing on a chip, photonic integration is necessary. Particularly in quantum technologies, which require a high precision of operation, avoiding bulky optical arrangements is in high demand. Scalable and robust photonic components open up a plethora of possibilities. The light guiding systems have to be able to cover a wide range of operational wavelengths and different light polarization states. In this work, we present the first numerical results for our approach of a PIC producing NIR circularly polarized light based on a Si3N4 material platform. This concept includes waveguides and metasurfaces that are easily integrable on the chip surface of many trapped-ion quantum computer architectures.

Metasurfaces, the two-dimensional variant of metamaterials, manipulate light in unique ways, opening up a whole new world of optical functionalities, ranging from optical imaging to quantum optics. High reflectivities and tailored phase profiles could allow such metamirrors to outperform conventional multilayer mirrors for high-precision optical interferometry due to their low thermal noise. Here, we design twin metamirrors with theoretical reflectivities of > 99.9 % at 1064 nm and 1550 nm. These mirrors can be implemented in bispectral low-noise optical cavities, which would reduce the number of cavities or can be used as a transfer cavity for quantum experiments like atomic clocks.