Hysteresis in phase volumes, compositions and interfacial roughness in model OPV-small-molecule/polymer thin-films.

Domain morphology and composition, and the structure of interfaces between domains are key factors in the performance and stability of organic photovoltaics (OPVs) fabricated from polymer/small-molecule blends. In this study, we investigate the evolution of composition, phase-volume and interfacial roughness in model polymer/small-molecule bilayers, in response to thermal annealing. Polystyrene/fullerene mixing is studied as a function of annealing temperature, using in situ neutron reflectivity, in thin-film bilayer samples comprising pure component or mixed layers. Remarkably, we discover that thermal annealing at temperatures around or above the reported glass transition temperatures, Tg, of the components can result in extensive mass-transfer between layers, that has the superficial appearance of equilibration, but leaves the layer compositions, thicknesses, and/or the interfacial composition profile in a non-equilibrium state. This is not merely a case of slow kinetics near Tg, as subsequent heating to higher temperatures, followed by cooling, reveals pronounced hysteresis in these systems. This has important implications for the measurement of equilibrium compositions in polymer/small-molecule mixtures for OPV applications, and for device stability during operation.

Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species.

The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.

More than a feeling: Effects of competitive asymmetry on human emotions.

Competitive interactions have important effects on human emotions. Both victory and defeat can evoke a wide range of emotional reactions, including joy, pride, anger, fear, sadness and shame. However, little is known about what determines this variety of contestants' affective responses. Therefore, the purpose of this study was to evaluate the effects of competitive asymmetry, a common and ecologically relevant feature of animal conflicts, on human emotional responses to winning or losing a contest. To test this hypothesis, we conducted two experiments, the first with high school students (n = 331) and the second with young athletes (n = 73), in which we manipulated the outcomes of successive matches in a non-athletic competition. Thus, by inducing the competitors' scores, ranging from closer to more decisive outcomes, we were able to define the degree of competitive asymmetry in victory and defeat conditions. We then assessed participants' emotional responses to a set of affective stimuli. In the defeat condition, we found in both studies an increase in the occurrence of anger and fear due to more symmetric contests. There were also more frequent reports of shame following more decisive defeats (Experiment 1) and of pride following closer victories (Experiment 2), which were seen neither for sadness nor joy in any of the studies. Supporting our hypothesis, emotional reactions triggered by asymmetries among contestants were consistent with the behavioral patterns commonly seen in symmetric and asymmetric animal conflict, such as dominance/aggressive and defensive/escape behaviors.

Mn substitution in the topological metal Zr2Te2P.

Results are reported for Mn intercalated Zr2Te2P, where x-ray diffraction , energy dispersive spectroscopy, and transmission electron microscopy measurements reveal that the van der Waals bonded Te-Te layers are partially filled by Zr and Mn ions. This leads to the chemical formulas Zr0.07Zr2Te2P and Mn0.06Zr0.03Zr2Te2P for the parent and substituted compounds, respectively. The impact of the Mn ions is seen in the anisotropic magnetic susceptibility, where Curie-Weiss fits to the data indicate that the Mn ions are in the divalent state. Heat capacity and electrical transport measurements reveal metallic behavior, but the electronic coefficient of the heat capacity (γMn≈ 36.6 mJ (mol·K2)-1) is enhanced by comparison to that of the parent compound. Magnetic ordering is seen atTM≈4 K, where heat capacity measurements additionally show that the phase transition is broad, likely due to the disordered Mn distribution. This transition also strongly reduces the electronic scattering seen in the normalized electrical resistance. These results show that Mn substitution simultaneously introduces magnetic interactions and tunes the electronic state, which improves prospects for inducing novel behavior in Zr2Te2P and the broader family of ternary tetradymites.

Effects of calcium ammonium nitrate fed to dairy cows on nutrient intake and digestibility, milk quality, microbial protein synthesis, and ruminal fermentation parameters.

We evaluated the effects of supplemental calcium ammonium nitrate (CAN) fed to dairy cows on dry matter (DM) intake, nutrient digestibility, milk quality, microbial protein synthesis, and ruminal fermentation. Six multiparous Holstein cows at 106 ± 14.8 d in milk, with 551 ± 21.8 kg of body weight were used in a replicated 3 × 3 Latin square design. Experimental period lasted 21 d, with 14 d for an adaptation phase and 7 d for sampling and data collection. Cows were randomly assigned to receive the following treatments: URE, 12 g of urea/kg of DM as a control group; CAN15, 15 g of CAN/kg of DM; and CAN30, 30 g of CAN/kg of DM. Supplemental CAN reduced DM intake (URE 19.0 vs. CAN15 18.9 vs. CAN30 16.5 kg/d). No treatment effects were observed for apparent digestibility of DM, organic matter, crude protein, ether extract, and neutral detergent fiber; however, CAN supplementation linearly increased nonfiber carbohydrate digestibility. Milk yield was not affected by treatments (average = 23.1 kg/d), whereas energy-corrected milk (ECM) and 3.5% fat-corrected milk (FCM) decreased as the levels of CAN increased. Nitrate residue in milk increased linearly (URE 0.30 vs. CAN15 0.33 vs. CAN30 0.38 mg/L); however, treatments did not affect nitrite concentration (average: 0.042 mg/L). Milk fat concentration was decreased (URE 3.39 vs. CAN15 3.35 vs. CAN30 2.94%), and the proportion of saturated fatty acids was suppressed by CAN supplementation. No treatment effects were observed on the reducing power and thiobarbituric acid reactive substances of milk, whereas conjugated dienes increased linearly (URE 47.6 vs. CAN15 52.7 vs. CAN30 63.4 mmol/g of fat) with CAN supplementation. Treatments had no effect on microbial protein synthesis; however, molar proportion of ruminal acetate and acetate-to-propionate ratio increased with CAN supplementation. Based on the results observed, supplementing CAN at 30 g/kg of DM should not be recommended as an optimal dose because it lowered DM intake along with ECM and 3.5% FCM, although no major changes were observed on milk quality and ruminal fermentation.

Rapid encoding of musical tones discovered in whole-brain connectivity.

Information encoding has received a wide neuroscientific attention, but the underlying rapid spatiotemporal brain dynamics remain largely unknown. Here, we investigated the rapid brain mechanisms for encoding of sounds forming a complex temporal sequence. Specifically, we used magnetoencephalography (MEG) to record the brain activity of 68 participants while they listened to a highly structured musical prelude. Functional connectivity analyses performed using phase synchronisation and graph theoretical measures showed a large network of brain areas recruited during encoding of sounds, comprising primary and secondary auditory cortices, frontal operculum, insula, hippocampus and basal ganglia. Moreover, our results highlighted the rapid transition of brain activity from primary auditory cortex to higher order association areas including insula and superior temporal pole within a whole-brain network, occurring during the first 220 ms of the encoding process. Further, we discovered that individual differences along cognitive abilities and musicianship modulated the degree centrality of the brain areas implicated in the encoding process. Indeed, participants with higher musical expertise presented a stronger centrality of superior temporal gyrus and insula, while individuals with high working memory abilities showed a stronger centrality of frontal operculum. In conclusion, our study revealed the rapid unfolding of brain network dynamics responsible for the encoding of sounds and their relationship with individual differences, showing a complex picture which extends beyond the well-known involvement of auditory areas. Indeed, our results expanded our understanding of the general mechanisms underlying auditory pattern encoding in the human brain.

A dual high-energy radiography platform with 15 µm resolution at the National Ignition Facility.

To study matter at extreme densities and pressures, we need mega laser facilities such as the National Ignition Facility as well as creative methods to make observations during timescales of a billionth of a second. To facilitate this, we developed a platform and diagnostic to characterize a new point-projection radiography configuration using two micro-wires irradiated by a short pulse laser system that provides a large field of view with up to 3.6 ns separation between images. We used tungsten-carbide solid spheres as reference objects and inferred characteristics of the back-lighter source using a forward-fitting algorithm. The resolution of the system is inferred to be 15 µm (using 12.5 µm diameter wires). The bremsstrahlung temperature of the source is 70-300 keV, depending on laser energy and coupling efficiency. By adding the images recorded on multiple stacked image plates, the signal-to-noise of the system is nearly doubled. The imaging characterization technique described here can be adapted to most point-projection platforms where the resolution, spectral contrast, and signal-to-noise are important.

Integrating ecosystem services into sustainable landscape management: A collaborative approach.

The Paiva River is considered one of the least polluted rivers in Europe and its watershed has a high conservation value. However, the Paiva River basin suffers pressures related with recurrent disturbances in land use, such as forest fires, agricultural activities, urbanization and pressures that affect the natural hydromorphological conditions and the continuity of watercourses. Blue and Green Infrastructures (BGINs) emerge to improve biodiversity, sustainability and the supply of ecosystem services while improving socioeconomic aspects. Thus, this article aims to identify priority areas in the basin, for intervention with these infrastructures. For that, a spatial multicriteria decision analysis (MDCA) was carried out according to several data related to the Paiva River Basin. As local politicians and responsible entities for the natural resources management are the main experts on the problems and their possible solutions at the local level, they were involved in this decision-making model. Therefore, these specialized stakeholders did the weighting assignment according to the most or least importance of the same for the work. The map of priority locations to implement BGINs was obtained in the sequel. To the top 5 priority areas, stakeholders attributed the best solutions based on nature. The most recommended BGINs were recovery/maintenance of riparian vegetation and conservation and reforestation of the native forest, both presented in four of the five areas, and introduction of fuel management strips presented in three of the five areas. Thus, we concluded that it is extremely important to include the communities and the competent entities of nature and environment management in scientific projects related to conservation, forming a synergy that makes it possible to combine scientific knowledge with local experience acquired in the field. This project uses a very flexible methodology of local data and can be a great example to be implemented in other hydrographic basins anywhere in the world.

Which One Is the Best for Living Donation: A Multiple-Artery Left Kidney Nephrectomy or a Right Kidney Nephrectomy?

INTRODUCTION: The current approach in living-donor kidney transplant is to preserve the best kidney for the donor and harvest the contralateral one. Due to a shorter renal vein and a greater incidence of venous thrombosis, left kidneys are more frequently elected. Notwithstanding, arterial anatomy may be complex and thus render the transplantation procedure more difficult and prone to complications. OBJECTIVES: To analyze the outcomes after multiple-artery left kidney nephrectomy (MALKN) and right kidney nephrectomy (RKN). RESULTS: Seventy-three cases were performed from 1999 to 2017 in our institution: 34 MALKN and 39 RKN. The mean operative time was significantly longer in MALKN. Warm ischemia time, donor and receptor hospital stay, and postoperative complications did not differ between groups. There was a positive correlation between renal arteries' ostia distance in MALKN and the duration of warm ischemia period. There was no significant difference in the incidence of acute tubular necrosis, first-year variations in serum creatinine, and glomerular filtration rate between groups. Long-term graft survival did not significantly differ between groups. Three cases of vein thrombosis after RKN were reported with graft loss. CONCLUSION: The safety and efficacy of MALKN does not differ from RKN, although there appears to be a higher incidence of vein thrombosis after right kidney transplantation. Despite being technically more demanding, particularly in cases with distant artery ostia, MALKN could be a better option than RKN for living donation, expanding the available donor pool, although more studies are needed to affirm this conclusion.

Discovery of key whole-brain transitions and dynamics during human wakefulness and non-REM sleep.

The modern understanding of sleep is based on the classification of sleep into stages defined by their electroencephalography (EEG) signatures, but the underlying brain dynamics remain unclear. Here we aimed to move significantly beyond the current state-of-the-art description of sleep, and in particular to characterise the spatiotemporal complexity of whole-brain networks and state transitions during sleep. In order to obtain the most unbiased estimate of how whole-brain network states evolve through the human sleep cycle, we used a Markovian data-driven analysis of continuous neuroimaging data from 57 healthy participants falling asleep during simultaneous functional magnetic resonance imaging (fMRI) and EEG. This Hidden Markov Model (HMM) facilitated discovery of the dynamic choreography between different whole-brain networks across the wake-non-REM sleep cycle. Notably, our results reveal key trajectories to switch within and between EEG-based sleep stages, while highlighting the heterogeneities of stage N1 sleep and wakefulness before and after sleep.

Microfluidic solvent extraction of poly(vinyl alcohol) droplets: effect of polymer structure on particle and capsule formation.

We investigate the formation of poly(vinyl alcohol) microparticles by the selective extraction of aqueous polymer solution droplets, templated by microfluidics and subsequently immersed in a non-solvent bath. The role of polymer molecular mass (18-105 kg mol-1), degree of hydrolysis (88-99%) and thus solubility, and initial solution concentration (0.01-10% w/w) are quantified. Monodisperse droplets with radii ranging from 50 to 500 µm were produced at a flow-focusing junction with carrier phase hexadecane and extracted into ethyl acetate. Solvent exchange and extraction result in droplet shrinkage, demixing, coarsening and phase-inversion, yielding polymer microparticles with well-defined dimensions and internal microstructure. Polymer concentration, varied from below the overlap concentration c* to above the concentrated crossover c**, as estimated by viscosity measurements, was found to have the largest impact on the final particle size and extraction timescale, while polymer mass and hydrolysis played a secondary role. These results are consistent with the observation that the average polymer concentration upon solidification greatly exceeds c**, and that the internal microparticle porosity is largely unchanged. However, reducing the initial polymer concentration to well below c* (approximately 100×) and increasing droplet size yields thin-walled (100's of nm) capsules which controllably crumple upon extraction. The symmetry of the process can be readily broken by imposing extraction conditions at an impermeable surface, yielding large, buckled, cavity morphologies. Based on these results, we establish robust design criteria for polymer capsules and particles, demonstrated here for poly(vinyl alcohol), with well-defined shape, dimensions and internal microstructure.

Diversity and genetic structure of the native Brazil nut tree (Bertholletia excelsa Bonpl.) population.

The present study was carried out in a native Brazil nut tree population (Bertholletia excelsa Bonpl., Lecythidaceae) to assess its genetic diversity and structure. Ten microsatellite markers were used to genotype 198 adult trees (B. excelsa). The population presented high genetic diversity and inbreeding absence rates. The empirical Bayesian method showed three distinct groups in the structure of this population. Molecular analysis of variance showed 98% variability within groups, and 2% between groups. The genetic divergence (FST) indicated little difference between groups; thus, suggesting efficient gene flow between the analyzed B. excelsa adult trees.

Osteochondritis Dissecans of the Capitellum: A Case Report of Successful Arthroscopic Treatment.

Introduction. Osteochondritis dissecans (OCD) of the capitellum is a localized disorder of the subchondral bone, in a region with limited healing capacity. Although its aetiology is still unknown, it has been associated with repetitive microtrauma. The natural history of this disease involves the evolution for degenerative joint disease in approximately half of the patients, with early identification and treatment being critical to optimizing the outcome. Case Presentation. We present a rare case in our practice, illustrating a capitellar OCD in a fifteen-year-old White male without an identified cause of repetitive microtrauma. Conclusion. In this case prompt diagnosis and arthroscopic-assisted treatment led to a successful result.

Impact of solution phase behaviour and external fields on thin film morphology: PCBM and RRa-P3HT model system.

We report the impact of the ternary solution phase behaviour on the film morphology and crystallization of a model polymer:fullerene system. We employ UV-Vis absorption spectroscopy, combined with sequential filtration and dilution, to establish the phase diagram for regio-random poly(3-hexylthiophene-2,5-diyl) and phenyl-C61-butyric acid methyl ester (PCBM) in chlorobenzene. Films are systematically cast from one- and two-phase regions decoupling homogeneous and heterogenous nucleation, and the role of pre-formed aggregates from solutions. Increasing annealing temperature from 120 to 200 °C reveals a highly non-monotonic nucleation profile with a maximum at 170 °C, while the crystal growth rate increases monotonically. UV ozonolysis is employed to vary substrate energy, and found to increase nucleation rate and to promote a binary crystallization process. As previously found, exposure to light, under an inert atmosphere, effectively suppresses homogeneous nucleation; however, it has a considerably smaller effect on heterogeneous nucleation, either from solution aggregates or substrate-driven. Our results establish a quantitative link between solution thermodynamics, crystallization and provide insight into morphological design based on processing parameters in a proxy organic photovoltaic system.

Endemic species may have complex histories: within-refugium phylogeography of an endangered Iberian vole.

Glacial refugia protected and promoted biodiversity during the Pleistocene, not only at a broader scale, but also for many endemics that contracted and expanded their ranges within refugial areas. Understanding the evolutionary history of refugial endemics is especially important in the case of endangered species to recognize the origins of their genetic structure and thus produce better informed conservation practices. The Iberian Peninsula is an important European glacial refugium, rich in endemics of conservation concern, including small mammals, such as the Cabrera vole (Microtus cabrerae). This near-threatened rodent is characterized by an unusual suite of genetic, life history and ecological traits, being restricted to isolated geographic nuclei in fast-disappearing Mediterranean subhumid herbaceous habitats. To reconstruct the evolutionary history of the Cabrera vole, we studied sequence variation at mitochondrial, autosomal and sex-linked loci, using invasive and noninvasive samples. Despite low overall mitochondrial and nuclear nucleotide diversities, we observed two main well-supported mitochondrial lineages, west and east. Phylogeographic modelling in the context of the Cabrera vole's detailed fossil record supports a demographic scenario of isolation of two populations during the Last Glacial Maximum from a single focus in the southern part of the Iberian Peninsula. In addition, our data suggest subsequent divergence within the east, and secondary contact and introgression of the expanding western population, during the late Holocene. This work emphasizes that refugial endemics may have a phylogeographic history as rich as that of more widespread species, and conservation of such endemics includes the preservation of that genetic legacy.

Karyotype diversity and genome size variation in Neotropical Maxillariinae orchids.

Orchidaceae is a widely distributed plant family with very diverse vegetative and floral morphology, and such variability is also reflected in their karyotypes. However, since only a low proportion of Orchidaceae has been analysed for chromosome data, greater diversity may await to be unveiled. Here we analyse both genome size (GS) and karyotype in two subtribes recently included in the broadened Maxillariinea to detect how much chromosome and GS variation there is in these groups and to evaluate which genome rearrangements are involved in the species evolution. To do so, the GS (14 species), the karyotype - based on chromosome number, heterochromatic banding and 5S and 45S rDNA localisation (18 species) - was characterised and analysed along with published data using phylogenetic approaches. The GS presented a high phylogenetic correlation and it was related to morphological groups in Bifrenaria (larger plants - higher GS). The two largest GS found among genera were caused by different mechanisms: polyploidy in Bifrenaria tyrianthina and accumulation of repetitive DNA in Scuticaria hadwenii. The chromosome number variability was caused mainly through descending dysploidy, and x=20 was estimated as the base chromosome number. Combining GS and karyotype data with molecular phylogeny, our data provide a more complete scenario of the karyotype evolution in Maxillariinae orchids, allowing us to suggest, besides dysploidy, that inversions and transposable elements as two mechanisms involved in the karyotype evolution. Such karyotype modifications could be associated with niche changes that occurred during species evolution.

Extracellular matrix microarrays to study inductive signaling for endoderm specification.

During tissue development, stem and progenitor cells are faced with fate decisions coordinated by microenvironmental cues. Although insights have been gained from in vitro and in vivo studies, the role of the microenvironment remains poorly understood due to the inability to systematically explore combinations of stimuli at a large scale. To overcome such restrictions, we implemented an extracellular matrix (ECM) array platform that facilitates the study of 741 distinct combinations of 38 different ECM components in a systematic, unbiased and high-throughput manner. Using embryonic stem cells as a model system, we derived definitive endoderm progenitors and applied them to the array platform to study the influence of ECM, including the interactions of ECM with growth factor signaling, on the specification of definitive endoderm cells towards the liver and pancreas fates. We identified ECM combinations that influence endoderm fate decisions towards these lineages, and demonstrated the utility of this platform for studying ECM-mediated modifications to signal activation during liver specification. In particular, defined combinations of fibronectin and laminin isoforms, as well as combinations of distinct collagen subtypes, were shown to influence SMAD pathway activation and the degree of hepatic differentiation. Overall, our systematic high-throughput approach suggests that ECM components of the microenvironment have modulatory effects on endoderm differentiation, including effects on lineage fate choice and cell adhesion and survival during the differentiation process. This platform represents a robust tool for analyzing effects of ECM composition towards the continued improvement of stem cell differentiation protocols and further elucidation of tissue development processes. STATEMENT OF SIGNIFICANCE: Cellular microarrays can provide the capability to perform high-throughput investigations into the role of microenvironmental signals in a variety of cell functions. This study demonstrates the utility of a high-throughput cellular microarray approach for analyzing the effects of extracellular matrix (ECM) in liver and pancreas differentiation of endoderm progenitor cells. Despite an appreciation that ECM is likely involved in these processes, the influence of ECM, particularly combinations of matrix proteins, had not been systematically explored. In addition to the identification of relevant ECM compositions, this study illustrates the capability of the cellular microarray platform to be integrated with a diverse range of cell fate measurements, which could be broadly applied towards the investigation of cell fate regulation in other tissue development and disease contexts.

A Minimal Invasive Method to Forecast the Effects of Anthropogenic Disturbance on Tropical Cave Beetle Communities.

Many tropical landscapes are changing rapidly, with uncertain outcomes for biodiversity, landscape function, and the corresponding landscape services. Therefore, monitoring and adaptively managing the drivers and consequences of landscape change while sustaining the production of essential resources have become research and policy priorities. In this perspective, we have applied a recent framework, the stochastic dynamic methodology (StDM), with the purpose of understanding the effects of natural and anthropogenic disturbances on caves' integrity using cave beetle communities (Coleoptera) as ecological indicators. The proposed method was preceeded by a generalized linear model for discriminating significant relationships between the selected indicators, the structural changes in the caves, and the epigean habitats associated. The obtained results showed different ecological trends in response to the environmental changes. Overall, the simulation results seem to demonstrate the StDM reliability in determining the effects of habitat dynamics, that is, the expansion of agricultural activities, in areas near the caves in the structure of cave beetle communities. The applied method, based on universal information-theoretic principles, can be easily implemented and interpreted by environmental managers and decision makers, enabling anticipating impacts and supporting the development of measures aimed at minimizing the identified problems.