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The presence of outcrops and soil (regolith) rich in opaline silica (∼65–92 wt % SiO2) in association with volcanic materials adjacent to the “Home Plate” feature in Gusev crater is evidence for hydrothermal conditions. The Spirit rover has supplied a diverse set of observations that are used here to better understand the formation of silica and the activity, abundance, and fate of water in the first hydrothermal system to be explored in situ on Mars. We apply spectral, chemical, morphological, textural, and stratigraphic observations to assess whether the silica was produced by acid sulfate leaching of precursor rocks, by precipitation from silica‐rich solutions, or by some combination. The apparent lack of S enrichment and the relatively low oxidation state of the Home Plate silica‐rich materials appear inconsistent with the originally proposed Hawaiian analog for fumarolic acid sulfate leaching. The stratiform distribution of the silica‐rich outcrops and their porous and brecciated microtextures are consistent with sinter produced by silica precipitation. There is no evidence for crystalline quartz phases among the silica occurrences, an indication of the lack of diagenetic maturation following the production of the amorphous opaline phase. Key Points Opaline silica adjacent to Home Plate occurs in stratiform outcrops Morphology and texture of opaline silica outcrops is consistent with sinter No evidence for diagentic maturation of the amorphous opal phase

The merger of divergent genomes, via hybridization or allopolyploidization, frequently results in a ‘genomic shock’ that induces a series of rapid genetic and epigenetic modifications as a result of conflicts between parental genomes. This conflict among the subgenomes routinely leads one subgenome to become dominant over the other subgenome(s), resulting in subgenome biases in gene content and expression. Recent advances in methods to analyze hybrid and polyploid genomes with comparisons to extant parental progenitors have allowed for major strides in understanding the mechanistic basis for subgenome dominance. In particular, our understanding of the role that homoeologous exchange might play in subgenome dominance and genome evolution is quickly growing. Here we describe recent discoveries uncovering the underlying mechanisms and provide a framework to predict subgenome dominance in hybrids and allopolyploids with far-reaching implications for agricultural, ecological, and evolutionary research.

Spike timing is thought to play a critical role in neural computation and communication. Methods for adjusting spike timing are therefore of great interest to researchers and clinicians alike. Transcranial electrical stimulation (tES) is a noninvasive technique that uses weak electric fields to manipulate brain activity. Early results have suggested that this technique can improve subjects’ behavioral performance on a wide range of tasks and ameliorate some clinical conditions. Nevertheless, considerable skepticism remains about its efficacy, especially because the electric fields reaching the brain during tES are small, whereas the likelihood of indirect effects is large. Our understanding of its effects in humans is largely based on extrapolations from simple model systems and indirect measures of neural activity. As a result, fundamental questions remain about whether and how tES can influence neuronal activity in the human brain. Here, we demonstrate that tES, as typically applied to humans, affects the firing patterns of individual neurons in alert nonhuman primates, which are the best available animal model for the human brain. Specifically, tES consistently influences the timing, but not the rate, of spiking activity within the targeted brain region. Such effects are frequency- and location-specific and can reach deep brain structures; control experiments show that they cannot be explained by sensory stimulation or other indirect influences. These data thus provide a strong mechanistic rationale for the use of tES in humans and will help guide the development of future tES applications.

The geochemical characterizations of the Upper Eocene carbonates of the Abu Rimth (Ab. Rth) Formation were used to shade more light on the occurrence, distribution and ecological implications of (REEs) & (TEs) elements in carbonates for Abu Rimth Plateau (Ab. Rth Formation). This article discusses the distribution and concentration of La, Ce, Sc and Y with environmental implications for the total REEs group as well as to determination of their origin and post-depositional alteration. The chemical results indicated that the studied carbonates show high enrichment of Ca and poor enrichment of Na 2 O, K 2 O, Al 2 O 3 and Fe 2 O 3 with intermediated enrichment of SiO 2. TEs contents pointed out that these carbonates were accumulated under marine environment characterized by, high salinity and hot climatic conditions. The redox elements and U/Th ratios (0.09) revealed that these studied carbonate rocks were formed in oxic environment. The average Rb/Sr (0.001) and the LREE/HREE (0.99) in the studied carbonate samples revealed that the prevalence of low intensity of weathering. Average content of the (REEs) and (TEs) are arranged as the following; in the studied samples. The Redox-sensitive REE elements and the significant negative Ce anomaly were reflecting these carbonates were deposited in oxic-seawater environments. The pollution indices of (REEs) and (TEs) revealed that the current samples are commonly show low polluation and ecological risk. These facts support the carbonate rocks of Abu Rimth Formation are friendly environmental and suitable for building and several industries.

Thermal energy storage (TES) is the most suitable solution found to improve the concentrating solar power (CSP) plant’s dispatchability. Molten salts used as sensible heat storage (SHS) are the most widespread TES medium. However, novel and promising TES materials can be implemented into CSP plants within different configurations, minimizing the TES costs and increasing the working temperature to improve the thermal performance of the associated power block. The first objective of this review is to provide an overview of the most widespread CSP technologies, TES technologies and TES-CSP configurations within the currently operational facilities. Once this information has been compiled, the second aim is to collect and present the existing European and North American TES-CSP Research and Development (R&D) projects within the last decade (2011–2021). Data related to these projects such as TES-CSP configuration path, TES and CSP technologies applied, storage capacity, power block associated and the levelized cost of electricity (LCOE) of the commercial up-scaling project are presented. In addition, project information such as location, research period, project leader and budget granted are also extracted. A timeline of the R&D projects launched from 2011 is built, showing the technology readiness level (TRL) achieved by the end of the project.

Transcranial alternating current stimulation (tACS) has been repeatedly demonstrated to increase power of endogenous brain oscillations in the range of the stimulated frequency after stimulation. In the alpha band this aftereffect has been shown to persist for at least 30 min. However, in most experiments the aftereffect exceeded the duration of the measurement. Thus, it remains unclear how the effect develops beyond these 30 min and when it decays. The current study aimed to extend existing findings by monitoring the physiological aftereffect of tACS in the alpha range for an extended period of 90 min post-stimulation. To this end participants received either 20 min of tACS or sham stimulation with intensities below their individual sensation threshold at the individual alpha frequency (IAF). Electroencephalogram (EEG) was acquired during 3 min before and 90 min after stimulation. Subjects performed a visual vigilance task during the whole measurement. While the enhanced power in the individual alpha band did not return back to pre-stimulation baseline in the stimulation group, the difference between stimulation and sham diminishes after 70 min due to a natural alpha increase of the sham group.

Thermal energy storage (TES) looks to be a promising technology for recovering waste heat or other intermittent heat sources, especially if it is coupled with the organic Rankine cycle (ORC) system. This system may use a variety of heat storage materials, including solids, liquids, and phase change materials (PCM). This article discusses the use of PCM as a thermal energy storage material in TES systems coupled with ORC systems. Other TES configurations may be used in ORC; however, in this article, the TES is solely used in heat exchangers, i.e., evaporator and liquid heater. The goal of this research is to establish a dimensionless storage mass parameter for sizing TES-evaporator (TES-EVA) or TES-liquid heater (TES-LH) devices for ORCs. Furthermore, the model of this system was created in the MATLAB environment using the chosen hydrocarbons as ORC working fluids. The obtained modelling results provide a novel point of view that scientists and engineers may employ while developing the TES-EVA or TES-LH utilizing PCM for ORC.

Feedhorn- and orthomode transducer- (OMT) coupled transition edge sensor (TES) bolometers have been designed and micro-fabricated to meet the optical specifications of the LiteBIRD high frequency telescope (HFT) focal plane. We discuss the design and optical characterization of two LiteBIRD HFT detector types: dual-polarization, dual-frequency-band pixels with 195/280 GHz and 235/337 GHz band centers. Results show well-matched passbands between orthogonal polarization channels and frequency centers within 3% of the design values. The optical efficiency of each frequency channel is conservatively reported to be within the range 0.64 - 0.72, determined from the response to a cryogenic, temperature-controlled thermal source. These values are in good agreement with expectations and either exceed or are within 10% of the values used in the LiteBIRD sensitivity forecast. Lastly, we report a measurement of loss in Nb/SiN x /Nb microstrip at 100 mK and over the frequency range 200–350 GHz, which is comparable to values previously reported in the literature.

Mid‐tropospheric Carbonyl sulfide (OCS) retrievals from the Tropospheric Emission Spectrometer (TES) are utilized to study OCS distributions during the dry/wet seasons over the Amazon rainforest. TES OCS retrievals reveal positive OCS anomalies (∼16 ppt) over the central and southern parts of the Amazon during August–October (dry season) compared to January–March (wet season). There is less OCS taken up by vegetation and soil and more OCS released from biomass burning during the dry season, which causes an increase in OCS concentrations. Strong sinking air during the dry season also helps to trap OCS and this contributes to positive OCS anomalies. MOZART‐4 model captures positive OCS anomalies over the central and southern regions of the Amazon and negative OCS anomalies over the northern part of the Amazon, which are similar to those from TES mid‐tropospheric OCS retrievals. Our studies can help us better understand OCS variations and photosynthetic activities. Plain Language Summary As a photosynthetic tracer, OCS can help us better understand photosynthetic activities, the biosphere‐atmosphere interaction, and the carbon sink. There are positive OCS anomalies (∼16 ppt) over the central and southern parts of the Amazon during August–October (dry season), which is related to reduced OCS uptake from vegetation and soil, enhanced OCS emission from biomass burning, and strengthened sinking air. MOZART‐4 is used to simulate the OCS variations during dry/wet seasons. Model results are similar to those from Tropospheric Emission Spectrometer OCS retrievals. However, there are some differences between the spatial distributions of OCS in the MOZART‐4 model and the satellite retrievals. Results in this study can help us better understand the variability of OCS and photosynthetic activities over the Amazon rainforest, which is the biggest rainforest and one of the largest sinks of OCS. Key Points Tropospheric Emission Spectrometer OCS concentrations are higher over the central and southern parts of the Amazon during the dry season than the wet season High OCS concentrations are related to reduced vegetation uptake, enhanced biomass burning, and increased sinking air MOZART‐4 captures the observed positive OCS anomalies over the central and southern Amazon during August–October (dry season)

Disposing of waste tires is a major environmental and economic issue. Different recycling methods have been studied to account for its re-usage. This project aims to evaluate the possible usage of shredded waste tires in thermal energy storage (TES) applications, whether they are sensible or latent materials. An experimental setup has been developed with seven compartments. Each compartment contains different TES materials, including tire crumbs, paraffin wax, paraffin wax with shredded tires, pebbles, pebbles with shredded tires, concrete, and concrete with shredded tires. In all cases of the mixture, the base materials are 60%vol, and the tire crumbs are 40%vol. The experimental included three locations for temperature measurements in each compartment, solar irradiation, and ambient temperature. The tests were carried out from 9:00 a.m. till 7:00 p.m. and repeated for five days to account for the weather’s daily change. Results revealed that mixed 60%vol pebbles and 40%vol shredded tires have the highest recorded temperature, at 112.5 °C, with a 39.5% increment compared to pure pebbles. The interesting finding is that the added tire crumbs reduced the storage capacity of the paraffin wax, which is latent TES material. At the same time, it increased the storage capacity of the concrete and pebbles, which are sensible TES materials. Adding 40%vol of tire crumbs to the paraffin wax has a negative effect, where the thermal storage capacity is reduced by 43%, and the discharge capacity is reduced by 57%. In contrast, the concrete and the pebbles show enhanced storage capacity. Adding 40%vol of crumbs to the concrete increased the charging capacity by 54% and discharging capacity by 33.7%. The 40%vol added tire crumbs to the pebbles increased its charging capacity by 25% and the discharging capacity by 33%. The rudimentary assessment encourages further investigations on using the wasted tires crumbs for TES. The results reveal the probability of a circular economy using wasted tires with sensible TES for solar-to-thermal energy conversion.