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Due to the intriguing optical and electronic properties, 2D materials are promising for next generation optoelectronic and electric device applications. Exploring new 2D materials with novel physical properties is rewarding for this area. In this work, we systematically investigated the optoelectronic properties of 2D metal thiophosphate SnP2S6 with a unique nanoporous structure. The intermediate bandgap makes SnP2S6 a good candidate for both the channel and gate dielectric materials in the transistor device. SnP2S6 showed good photoresponse properties. In addition, the MoS2 transistor with SnP2S6 as a dielectric layer showed a high dielectric constant (≈23) and a low subthreshold slope down to 69.4 mV dec−1, and it presented 0.1 pA scale leakage current, a threshold voltage as low as 1.1 V, an ON/OFF ratio reaching 107 and negligible hysteresis with high stability and reproducibility. This work could open up new avenues for the discovery of new metal thiophosphate systems for future device applications. [ABSTRACT FROM AUTHOR]

Microbial interactions play a key role in ecosystem functioning, with nutrient availability as an important determinant. Although phylogenetically distant bacteria and fungi commonly co-occur in nature, information on their cross-kingdom interactions under unstable, extreme environments remains poor. Hence, the aims of this work were to evaluate potential in vitro interactions among fungi and bacteria isolated from a phosphorous oligotrophic aquatic system in the Cuatro Ciénegas Basin, Mexico, and to test the nutrients-based shifts. We assessed growth changes in bacteria (Aeromonas and Vibrio) and fungi (Coprinellus micaceus , Cladosporium sp., and Aspergillus niger) on co-cultures in relation to monocultures under diverse nutrient scenarios on Petri dishes. Interactions were explored using a network analysis, and a metabolome profiling for specific taxa. We identified nutrient-dependent patterns, as beneficial interactions dominated in low-nutrients media and antagonistic interactions dominated in rich media. This suggests that cross-kingdom synergistic interactions might favor microbial colonization and growth under low nutrient conditions, representing an adaptive trait to oligotrophic environments. Moreover, our findings agree with the stress-gradient hypothesis, since microbial interactions shifted from competition to cooperation as environmental stress (expressed as low nutrients) increased. At a functional level consistent differences were detected in the production of secondary metabolites, agreeing with plate bioassays. Our results based on culture experiments, provides evidence to understand the complexity of microbial dynamics and survival in phosphorous-depleted environments. [ABSTRACT FROM AUTHOR]

Abstract: Warming is among the major drivers of changes in biotic interactions and, in turn, ecosystem functioning. The decomposition process occurs in a chain of facilitative interactions between detritivores and microorganisms. It remains unclear, however, what effect warming may have on the interrelations between detritivores and microorganisms, and the consequences for the functioning of natural freshwater ecosystems. To address these gaps, we performed a field experiment using tank bromeliads and their associated aquatic fauna. We manipulated the presence of bacteria and detritivorous macroinvertebrates (control, “bacteria,” and “bacteria + macroinvertebrates”) under ambient and warming scenarios, and analyzed the effects on the microorganisms and ecosystem functioning (detritus mass loss, colored dissolved organic matter, and nitrogen flux). We applied antibiotic solution to eliminate or reduce bacteria from control bromeliads. After 60 days incubation, bacterial density was higher in the presence than in the absence of macroinvertebrates. In the absence of macroinvertebrates, temperature did not influence bacterial density. However, in the presence of macroinvertebrates, bacterial density decreased by 54% with warming. The magnitude of the effects of organisms on ecosystem functioning was higher in the combined presence of bacteria and macroinvertebrates. However, warming reduced the overall positive effects of detritivores on bacterial density, which in turn, cascaded down to ecosystem functioning by decreasing decomposition and nitrogen flux. These results show the existence of facilitative mechanisms between bacteria and detritivores in the decomposition process, which might collapse due to warming. Detritivores seem to contribute to nutrient cycling as they facilitate bacterial populations, probably by increasing nutrient input (feces) in the ecosystem. However, increased temperature mitigated these beneficial effects. Our results add to a growing research body that shows that warming can affect the structure of aquatic communities, and highlight the importance of considering the interactive effects between facilitation and climatic drivers on the functioning of freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Environmental degradation may have strong effects on community assembly processes. We examined the assembly of bacterial and fungal communities in anthropogenically altered and near-pristine streams. Using pyrosequencing of bacterial and fungal DNA from decomposed alder Alnus incana leaves, we specifically examined if environmental degradation deterministically decreases or increases the compositional turnover of bacterial and fungal communities. Our results showed that near-pristine streams and anthropogenically altered streams supported distinct fungal and bacterial communities. The mechanisms assembling these communities were different in near-pristine and altered environments. Environmental disturbance homogenized bacterial communities, whereas fungal communities were more dissimilar in disturbed sites than in near-pristine sites. Compositional variation of both bacteria and fungi was related to water chemistry variables in disturbed sites, further implying the influence of environmental degradation on community assembly. Bacterial and fungal communities in near-pristine streams were weakly controlled by environmental factors, suggesting that the relative importance of niche-based versus neutral processes in assembling microbial communities may strongly depend on the spatial scale and local environmental context. Our results thus suggest that environmental degradation may strongly affect the composition and β-diversity of stream microbial communities colonizing leaf litter, and that the direction of the change can be different between bacteria and fungi. A better understanding of the environmental tolerances of microbes and the mechanisms assembling microbial communities in natural environmental settings is needed to predict how environmental alteration is likely to affect microbial communities. [ABSTRACT FROM AUTHOR]

Strongly correlated Fermi systems are among the most intriguing and fundamental systems in physics. We show that the herbertsmithite ZnCu(OH)Cl can be regarded as a new type of strongly correlated electrical insulator that possesses properties of heavy-fermion metals with one exception: it resists the flow of electric charge. We demonstrate that herbertsmithite's low-temperature properties are defined by a strongly correlated quantum spin liquid made with hypothetic particles such as fermionic spinons that carry spin 1/2 and no charge. Our calculations of its thermodynamic and relaxation properties are in good agreement with recent experimental facts and allow us to reveal their scaling behavior, which strongly resembles that observed in heavy-fermion metals. Analysis of the dynamic magnetic susceptibility of strongly correlated Fermi systems suggests that there exist at least two types of its scaling. [ABSTRACT FROM AUTHOR]

Ultrasonic method was applied for evaluation of piezoelectricity in layered crystals of CuInP2S6 family and of La(Mg1/2Ti1/2)O3-BaTiO3 (BT-LMT) electroceramics. Amplitude of electric signal appearing on the plate under ultrasonic excitation is proportional to appropriate piezoelectric constant. In CuInP2S6 family piezosensitivity was observed only in low temperature phase. In BT-LMT ceramics piezosensitivity had anomalies at low temperature phase transitions and had long tails in the high temperature paraelectric phase. Field-induced hysteresis loops of such ultrasonically detected piezoelectric signal amplitude in the ferroelectric phase were observed. In the paraelectric phase field-induced piezosensitivity due to electrostriction appeared in layered crystals and BT-LMT ceramics when DC bias electric field was applied. In centrosymetric AgInP2Se6 crystals comparatively large piezoelectric sensitivity was induced due to electrostriction by DC bias electric field applied along c-axis. [ABSTRACT FROM AUTHOR]

In this contribution, we present results of piezoelectric and ultrasonic investigations of CuInP2S6 family solid solutions where various Cu was substituted with Ag and S to Se. The ultrasonic attenuation, velocity and piezoelectric sensitivity anomalies were recorded at phase transitions in these new compounds. It was shown that with increasing Ag and Se content in the solid solutions, the phase transition temperature decreases. The phase transition type changes to the second order in Ag0.1Cu0.9InP2S6crystal. Pure AgInP2S6 and AgInP2Se6 crystals did not reveal the phase transition in the temperature range 100-300 K. The piezoelectric sensitivity in these pure crystals was observed only when DC bias electric field was applied along direction normal to layers. In this case the piezoelectric sensitivity appeared due to electrostriction. [ABSTRACT FROM AUTHOR]

Bacteria and fungi often share a common substrate, and their spatial proximity in many environments has lead to either synergistic or antagonistic interactions. In this paper, the interaction of bacterial and fungal decomposers from an aquatic environment was studied. We found indications of a tradeoff between fungal growth and tolerance towards bacteria. Fungal strains growing best in absence of bacteria were most severely affected by bacterial presence, while those less suppressed during co-existence with bacteria had lower maximal growth rates in bacterial absence. Additionally, we show that the antagonism between bacteria and fungi is connected to competition for substrate, but that this competition can be drastically altered if fungi are given an opportunity to establish before inoculation of bacteria. Established fungi out-competed bacteria, and gained higher biomass than in simultaneously inoculated treatments with higher substrate concentrations. [ABSTRACT FROM AUTHOR]