Glassy Materials Based Microdevices

Microtechnology has changed our world since the last century, when silicon microelectronics revolutionized sensor, control and communication areas, with applications extending from domotics to automotive, and from security to biomedicine. The present century, however, is also seeing an accelerating pace of innovation in glassy materials; as an example, glass-ceramics, which successfully combine the properties of an amorphous matrix with those of micro- or nano-crystals, offer a very high flexibility of design to chemists, physicists and engineers, who can conceive and implement advanced microdevices. In a very similar way, the synthesis of glassy polymers in a very wide range of chemical structures offers unprecedented potential of applications. The contemporary availability of microfabrication technologies, such as direct laser writing or 3D printing, which add to the most common processes (deposition, lithography and etching), facilitates the development of novel or advanced microdevices based on glassy materials. Biochemical and biomedical sensors, especially with the lab-on-a-chip target, are one of the most evident proofs of the success of this material platform. Other applications have also emerged in environment, food, and chemical industries. The present Special Issue of Micromachines aims at reviewing the current state-of-the-art and presenting perspectives of further development. Contributions related to the technologies, glassy materials, design and fabrication processes, characterization, and, eventually, applications are welcome

Factors influencing terrestriality in primates of the Americas and Madagascar

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (bodymass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use

Factors influencing terrestriality in primates of the Americas and Madagascar

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use

Primate nutritional ecology: the role of food selection, energy intake, and nutrient balancing in Mexican black howler monkey (Alouatta pigra) foraging strategies

Studying primate nutritional ecology is critical for addressing questions related to individual and group-based decision making, feeding ecology, life history, and reproductive success. However, understanding food selection is a complex task, and it requires integrating information on physiology, behavior, and the ecological and social environments in which the animals live. In this dissertation, I examined the nutritional ecology of Mexican black howler monkeys (Alouatta pigra), an endangered nonhuman primate species characterized by a high intraspecific variability in time spent feeding on leaves, fruits, flowers, and other items (such as bark and stems) across seasons and study sites. Howler monkeys are considered the most folivorous New World primates, with leaves accounting for up to 100% of feeding time during certain months. Given assumptions regarding the challenges faced by foragers exploiting difficult to digest or high fiber foods that also may contain plant secondary compounds, howlers are considered energy-limited. While howler monkeys do consume a leaf-heavy diet during certain seasons of the year, and possess certain anatomical and physiological traits such as a capacious colon where fermentation occurs, a relatively long food transit time for their body mass, and molars with high shearing crests that contribute to the efficient processing of leafy material, describing them as folivores is an oversimplification of their dietary ecology. In this 15-month field study, I combined ecological, behavioral, and phytochemical data to analyze patterns of patch and food choice, nutrient and energy intake, and nutrient balancing in two groups (n = 14) of black howler monkeys inhabiting a 1400-ha semi-deciduous forest (“El Tormento”) in Campeche, Mexico. By following a single individual and recording its complete diet over the course of a single day, the amount in grams of each resource consumed, and the phytochemical characteristic of the food ingested, I constructed complete daily dietary profiles for each focal animal, and analyzed individual food choices using the Geometric Framework for nutrition. The GF is a multidimensional approach in which variables such as different food components and the amount of ingested nutrients are viewed in geometric space. The first chapter examines the role of resource mixing (i.e., switching between patches characterized by different types of resources and proportions of macronutrients) in individual feeding patch choice and patch leaving decisions. The second chapter analyzes the effects of plant phytochemical characteristics, including macronutrients and minerals, on individual food selection. The third chapter utilizes nutritional geometry to explore the synergistic effects of multiple nutrients and energy requirements on howler food choice across three different seasons (rainy, dry, and nortes). Finally, in the fourth chapter I outline the major conclusions and contributions of this research. I found that resource mixing offered the strongest explanation for feeding patch choices of black howler monkeys. This is based on data indicating that individuals frequently switched among complementary food items (e.g., from mature fruits to young leaves, from young leaves to immature fruits), moving from a lower protein patch to a higher protein food patch and vice versa. Moreover, neither patch depletion, satiation, nor social factors (e.g., intra-group aggression) were found to play an important role in individuals’ decisions to leave a patch. During the dry and rainy seasons, indices of howler food selectivity did not correlate with the nutrient and energetic content of foods consumed. This is not expected in a nutrient maximization model, but is consistent with the expectations of nutrient balancing. Based on the amount of food ingested (grams dry weight), howler monkeys were characterized by a fruit dominated diet (58% fruits, 37% leaves, 5% flowers), but this pattern differed among seasons. Leaves (mainly mature) were the most consumed food items during the nortes (49.5%). However, despite temporal changes in food consumption and food availability, and despite the fact that the food items consumed by howlers at El Tormento contained on average ~11% available protein, high levels of condensed tannins, and a low protein-to-fiber ratio (0.4 for young and mature leaves), across seasons the howlers consumed on average 102 kJ of available protein per metabolic body mass per day and 628 kJ/mbm of total energy. These values surpassed their daily requirements for protein and metabolizable energy, and were higher than those reported for primates considered ripe fruit specialists such as spider monkeys (Ateles spp.). Maintaining a balance in daily protein and non-protein energy intake was the most consistent strategy adopted by howler monkeys across all seasons of the year. These findings support the idea that howler monkey feeding strategies enable them to translate energy into rapid growth rates and high reproductive output compared to other atelines. Finally, this research supports the increasing recognition of nutrient balancing as a dietary strategy used by nonhuman primates to exploit nutritionally imbalanced and complementary foods in order to meet their dietary needs

Editorial for the Special Issue on Glassy Materials Based Microdevices

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Evidence of alternative dietary syndromes and nutritional goals in the Genus Alouatta

Howler monkeys exploit diffi cult-to-digest and potentially toxic food items such as mature leaves and unripe fruits; persist across an extreme range of habitat types, including highly disturbed forests; and have the most widespread geographical distribution of any genus of New World primate. Given evidence of dietary variability in the amount of monthly fruit, leaf, and fl ower consumption, howler monkeys provide an instructive model for examining relationships among foraging strategies, activity budgets, and patterns of habitat utilization. In this chapter we examined evidence for interspecifi c differences in dietary patterns and nutritional ecology within the genus Alouatta and identifi ed three dietary ?syndromes? that are generally consistent with howler monkey phylogeny and biogeography. Specifically, we show that Mesoamerican howler monkeys and A. seniculus are characterized by a balanced leaf and fruit diet, Amazonian species by a fruit enriched diet, and Atlantic Forest and southern howler monkeys by a leaf-enriched diet. Finally, to be able to identify species-specifi c dietary strategies and syndromes across the primate Order, we recommend an approach that includes collecting data on feeding rates and the nutritional composition of the diet.Los monos aulladores consumen alimentos difíciles de digerir y que potencialmente contienen compuestos secundarios tóxicos como hojas maduras y frutos inmaduros; habitan en tipos de ambientes muy variados, incluyendo áreas altamente fragmentadas, y tienen la distribución geográfica más amplia de cualquier otro género de primates neotropicales. Debido a las conspicuas fluctuaciones mensuales en las cantidades de frutos, hojas y flores consumidos, los monos aulladores constituyen un modelo útil para examinar las relaciones entre estrategias de forrajeo, patrones de actividad y de utilización de hábitat en otros primates, incluyendo a los folívoros. En este capítulo examinamos la evidencia de diferencias interespecíficas en los patrones alimentarios y nutricionales dentro del género Alouatta, e identificamos tres “síndromes” alimentarios consistentes con los patrones filogenéticos y biogeográficos. En particular, mostramos que los monos aulladores de Mesoamérica y A. seniculus se caracterizan por tener una dieta balanceada de hojas y frutos, las especies del Amazonas por una dieta en la que predominan los frutos, y aquellas de la Foresta Atlántica y del Sur por una dieta en la que predominan las hojas. Finalmente, subrayamos la importancia de colectar datos sobre las tasas de ingestión de los alimentos y sobre la composición nutricional de la dieta para poder identificar estrategias y síndromes alimentarios especie-específicos en los primates.Fil: Garber, Paul A.. University of Illinois; Estados UnidosFil: Righini, Nicoletta. University of Illinois; Estados UnidosFil: Kowalewski, Miguel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Role of Preoperative Ultrasound Shear-Wave Elastography and Radiofrequency-Based Arterial Wall Tracking in Assessing the Vulnerability of Carotid Plaques: Preliminary Results

We aimed at evaluating the ability of point shear-wave elastography (pSWE) and of a radiofrequency (RF) echo-tracking-based method in preoperatively assessing the vulnerability of the carotid plaque in patients undergoing carotid endarterectomy (CEA) for significant asymptomatic stenosis. All patients who underwent CEA from 03/2021 to 03/2022 performed a preoperative pSWE and an RF echo-based wall evaluation of arterial stiffness using an Esaote MyLab ultrasound system (EsaoteTM, Genova, Italy) with dedicated software. The data derived from these evaluations (Young's modulus (YM), augmentation index (AIx), pulse-wave velocity (PWV)) were correlated with the outcome of the analysis of the plaque removed during the surgery. Data were analyzed on 63 patients (33 vulnerable and 30 stable plaques). In stable plaques, YM was significantly higher than in vulnerable plaques (49.6 + 8.1 kPa vs. 24.6 + 4.3 kPa, p = 0.009). AIx also tended to be slightly higher in stable plaques, even if it was not statistically significant (10.4 + 0.9% vs. 7.7 + 0.9%, p = 0.16). The PWV was similar (12.2 + 0.9 m/s for stable plaques vs. 10.6 + 0.5 m/s for vulnerable plaques, p = 0.16). For YM, values >34 kPa had a sensitivity of 50% and a specificity of 73.3% in predicting plaque nonvulnerability (area under the curve = 0.66). Preoperative measurement of YM by means of pSWE could be a noninvasive and easily applicable tool for assessing the preoperative risk of plaque vulnerability in asymptomatic patients who are candidates for CEA

Data from: Nutrient-specific compensation for seasonal cold stress in a free-ranging temperate colobine monkey

1. Homeostatic responses of animals to environmentally-induced changes in nutrient requirements provide a powerful basis for predictive ecological models, and yet such responses are virtually unstudied in the wild. 2. We tested for macronutrient-specific compensatory feeding responses by free-ranging golden snub-nosed monkeys (Rhinopithecus roxellana) inhabiting high altitude temperate forests where they experience a substantial difference in ambient temperature in cold winters vs. warmer springs. The monkeys had free access to natural foods throughout the year, and to ensure that any seasonal differences in nutrient intake were due to homeostatic compensation and not constraints on food availability, we studied the monkeys during periods in which they were provisioned with the same amount of supplementary foods in winter and spring. 3. Thermoregulatory energy costs in winter and spring were calculated using partitional calorimetric estimations of convective and radiative heat loss obtained from thermal imaging of free-ranging monkeys in situ. Daily nutrient intakes were measured using continuous focal follows (average 6.9 h/day) of free-ranging individuals (27 in spring and 28 in winter). 4. We used a nutritional geometry framework to integrate these data and test three predictions: i. In order to remain thermoneutral (balance heat loss with heat expenditure), golden snub-nosed monkeys decrease daily energy consumption during the spring compared to winter, ii. Decreased energy intake is accomplished specifically by reducing intake of the primary energetic nutrients, carbohydrate and lipid, relative to protein, and iii. The seasonal reduction in ingested fat and carbohydrate calories will quantitatively match the reduction in thermoregulatory costs in spring compared with winter. 5. Our results showed that energy intake in spring was reduced to almost half (55%) of that in winter. As predicted, this was achieved by specifically reducing fat and carbohydrate consumption with protein intake unchanged, by a quantity (326 kJ/mbm) that almost exactly matched the seasonal difference in the daily energetic costs of thermoregulation (329 kJ/mbm). 6. This is the first study to test for a match between nutrient-specific homeostatic compensation and environmentally-induced perturbations in nutrient requirements in free-ranging animals, and underpins the potential for the homeostasis framework to provide predictive power to ecological models