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Seven rocky planets orbit the nearby dwarf star TRAPPIST-1, providing a unique opportunity to search for atmospheres on small planets outside the Solar System1. Thanks to the recent launch of the James Webb Space Telescope (JWST), possible atmospheric constituents such as carbon dioxide (CO2) are now detectable2,3. Recent JWST observations of the innermost planet TRAPPIST-1 b showed that it is most probably a bare rock without any CO2 in its atmosphere4. Here we report the detection of thermal emission from the dayside of TRAPPIST-1 c with the Mid-Infrared Instrument (MIRI) on JWST at 15 µm. We measure a planet-to-star flux ratio of fp/f⁎ = 421 ± 94 parts per million (ppm), which corresponds to an inferred dayside brightness temperature of 380 ± 31 K. This high dayside temperature disfavours a thick, CO2-rich atmosphere on the planet. The data rule out cloud-free O2/CO2 mixtures with surface pressures ranging from 10 bar (with 10 ppm CO2) to 0.1 bar (pure CO2). A Venus-analogue atmosphere with sulfuric acid clouds is also disfavoured at 2.6σ confidence. Thinner atmospheres or bare-rock surfaces are consistent with our measured planet-to-star flux ratio. The absence of a thick, CO2-rich atmosphere on TRAPPIST-1 c suggests a relatively volatile-poor formation history, with less than 9.5 − 2.3 + 7.5 Earth oceans of water. If all planets in the system formed in the same way, this would indicate a limited reservoir of volatiles for the potentially habitable planets in the system.The detection of thermal emission from the rocky exoplanet TRAPPIST-1 c using the Mid-Infrared Instrument on the James Webb Space Telescope reveals a dayside brightness temperature that disfavours a thick, CO2-rich atmosphere. [ABSTRACT FROM AUTHOR]

Dry eye is a common ocular inflammatory disorder characterized by tear film instability and reduced tear production. There is increasing evidence that homeostasis of the ocular surface is impacted by the intestinal microbiome. We are interested in investigating the potential role of microbially produced small molecules in mediating the interaction between the intestinal microbiota and the ocular surface. One such molecule is butyrate, a short-chain fatty acid (SCFA) produced by certain members of the gut microbiota through fermentation of dietary fiber. Here we show that SCFA transporter SLC5A8 is expressed in vivo in murine conjunctival and corneal epithelium. Pre-treatment of in vitro corneal epithelial cultures or bone marrow-derived dendritic cells (BMDCs) with phenylbutyrate (PBA) reduces lipopolysaccharide-induced pro-inflammatory Tnf expression. Corneal epithelial cultures and BMDCs isolated from Slc5a8 knockout mice are unable to respond to PBA pre-treatment, suggesting that SLC5A8 is required for the protective effect of PBA. The treatment of mice undergoing desiccating stress (DS) with oral tributyrin, a prodrug form of butyrate, reduces inflammation at the ocular surface in vivo, and this effect partially requires SLC5A8. Finally, expression analysis on conjunctival tissue isolated from mice subjected to DS with and without tributyrin treatment revealed that treatment downregulated genes involved in Type I interferon signaling. Together these data support our hypothesis that SCFAs produced in the gut participate in the maintenance of ocular surface homeostasis. [ABSTRACT FROM AUTHOR]

The olfactomotor system is especially investigated by examining the sniffing in reaction to olfactory stimuli. The motor output of respiratory-independent muscles was seldomly considered regarding possible influences of smells. The Adaptive Force (AF) characterizes the capability of the neuromuscular system to adapt to external forces in a holding manner and was suggested to be more vulnerable to possible interfering stimuli due to the underlying complex control processes. The aim of this pilot study was to measure the effects of olfactory inputs on the AF of the hip and elbow flexors, respectively. The AF of 10 subjects was examined manually by experienced testers while smelling at sniffing sticks with neutral, pleasant or disgusting odours. The reaction force and the limb position were recorded by a handheld device. The results show, inter alia, a significantly lower maximal isometric AF and a significantly higher AF at the onset of oscillations by perceiving disgusting odours compared to pleasant or neutral odours (p < 0.001). The adaptive holding capacity seems to reflect the functionality of the neuromuscular control, which can be impaired by disgusting olfactory inputs. An undisturbed functioning neuromuscular system appears to be characterized by a proper length tension control and by an earlier onset of mutual oscillations during an external force increase. This highlights the strong connection of olfaction and motor control also regarding respiratory-independent muscles. [ABSTRACT FROM AUTHOR]

The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson's disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD. [ABSTRACT FROM AUTHOR]

The pathophysiology of Parkinson's disease (PD) is still not understood. There are investigations which show a changed oscillatory behaviour of brain circuits or changes in variability of, e.g., gait parameters in PD. The aim of this study was to investigate whether or not the motor output differs between PD patients and healthy controls. Thereby, patients without tremor are investigated in the medication off state performing a special bilateral isometric motor task. The force and accelerations (ACC) were recorded as well as the Mechanomyography (MMG) of the biceps brachii, the brachioradialis and of the pectoralis major muscles using piezoelectric-sensors during the bilateral motor task at 60% of the maximal isometric contraction. The frequency, a specific power ratio, the amplitude variation and the slope of amplitudes were analysed. The results indicate that the oscillatory behaviour of motor output in PD patients without tremor deviates from controls: thereby, the 95%-confidence-intervals of power ratio and of amplitude variation of all signals are disjoint between PD and controls and show significant differences in group comparisons (power ratio: p = 0.000–0.004, r = 0.441–0.579; amplitude variation: p = 0.000–0.001, r = 0.37–0.67). The mean frequency shows a significant difference for ACC (p = 0.009, r = 0.43), but not for MMG. It remains open, whether this muscular output reflects changes of brain circuits and whether the results are reproducible and specific for PD. [ABSTRACT FROM AUTHOR]

Most known terrestrial planets orbit small stars with radii less than 60 per cent of that of the Sun1,2. Theoretical models predict that these planets are more vulnerable to atmospheric loss than their counterparts orbiting Sun-like stars3–6. To determine whether a thick atmosphere has survived on a small planet, one approach is to search for signatures of atmospheric heat redistribution in its thermal phase curve7–10. Previous phase curve observations of the super-Earth 55 Cancri e (1.9 Earth radii) showed that its peak brightness is offset from the substellar point (latitude and longitude of 0 degrees)—possibly indicative of atmospheric circulation11. Here we report a phase curve measurement for the smaller, cooler exoplanet LHS 3844b, a 1.3-Earth-radii world in an 11-hour orbit around the small nearby star LHS 3844. The observed phase variation is symmetric and has a large amplitude, implying a dayside brightness temperature of 1,040 ± 40 kelvin and a nightside temperature consistent with zero kelvin (at one standard deviation). Thick atmospheres with surface pressures above 10 bar are ruled out by the data (at three standard deviations), and less-massive atmospheres are susceptible to erosion by stellar wind. The data are well fitted by a bare-rock model with a low Bond albedo (lower than 0.2 at two standard deviations). These results support theoretical predictions that hot terrestrial planets orbiting small stars may not retain substantial atmospheres. Phase curve measurements for the small (1.3 Earth radii) terrestrial exoplanet LHS 3844b show absence of a thick atmosphere, in agreement with theoretical predictions. [ABSTRACT FROM AUTHOR]

Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one such). Between one-quarter and one-half of white dwarfs have elements heavier than helium in their atmospheres, even though these elements ought to sink rapidly into the stellar interiors (unless they are occasionally replenished). The abundance ratios of heavy elements in the atmospheres of white dwarfs are similar to the ratios in rocky bodies in the Solar System. This fact, together with the existence of warm, dusty debris disks surrounding about four per cent of white dwarfs, suggests that rocky debris from the planetary systems of white-dwarf progenitors occasionally pollutes the atmospheres of the stars. The total accreted mass of this debris is sometimes comparable to the mass of large asteroids in the Solar System. However, rocky, disintegrating bodies around a white dwarf have not yet been observed. Here we report observations of a white dwarf-WD 1145+017-being transited by at least one, and probably several, disintegrating planetesimals, with periods ranging from 4.5 hours to 4.9 hours. The strongest transit signals occur every 4.5 hours and exhibit varying depths (blocking up to 40 per cent of the star's brightness) and asymmetric profiles, indicative of a small object with a cometary tail of dusty effluent material. The star has a dusty debris disk, and the star's spectrum shows prominent lines from heavy elements such as magnesium, aluminium, silicon, calcium, iron, and nickel. This system provides further evidence that the pollution of white dwarfs by heavy elements might originate from disrupted rocky bodies such as asteroids and minor planets. [ABSTRACT FROM AUTHOR]

Purpose: Life cycle assessment (LCA) can reveal valuable information pertaining to materials, water, and energy that will be consumed throughout a building's entire predicted life span; however, it is often underutilized in practice. Individuals in the architecture, engineering, and construction (AEC) community are in positions to influence the use of LCA. Thus, this article seeks to clarify the state of knowledge of LCA among this population and understand the perceived benefits of and barriers to its application. Methods: Building upon the researchers' results using focus groups, a national survey of AEC professionals, owners/clients, and related groups was developed to educe knowledge and perceptions within the AEC community. Existing literature suggests time and data demands, complexity, and cost to benefit ratio uncertainty among current LCA framework shortcomings. The survey was structured to further investigate these findings. Furthermore, the survey recorded both a self-assessed and measured level of each respondent's LCA understanding, which served as a validation for other responses. The information collected spanned a broad range, including LCA knowledge, LCA experience, perceived benefits and barriers to LCA adoption, software tool utilization, and LCA in conjunction with sustainability, in general, and with the Leadership in Energy and Environmental Design (LEED) program. Results and discussion: Respondents represented over a dozen AEC professions, approximately half being architects and engineers. Ninety percent reported having at least moderate familiarity with sustainability, and 62 % considered sustainability important in their projects for at least 4 years. Only 33 % of those individuals, however, used LCA in half of their projects or more, predominantly for energy analysis. A substantial percentage of respondents exhibited competency in defining LCA, but the disconnect between awareness and the use of LCA can be largely attributed to a perceived lack of demand. However, 86 % of respondents who currently use LCA reported being at least moderately likely to increase their usage of LCA in the future. Conclusions: The ability of an LCA to advance sustainability by informing decision-making and provide environmental impact information using a long-term, holistic perspective is valuable to most potential users. Additional benefits and barriers specific to the building sector were revealed in this study, and the factors that may contribute to these perceptions were explored, the knowledge of which can be beneficial in efforts to optimize LCA adoption. Finally, since Leadership in Energy and Environmental Design (LEED) version 4.0 explicitly includes LCA, we anticipate a greater integration and use of LCA in the AEC community. [ABSTRACT FROM AUTHOR]

Purpose: This paper uses a dynamic life cycle assessment (DLCA) approach and illustrates the potential importance of the method using a simplified case study of an institutional building. Previous life cycle assessment (LCA) studies have consistently found that energy consumption in the use phase of a building is dominant in most environmental impact categories. Due to the long life span of buildings and potential for changes in usage patterns over time, a shift toward DLCA has been suggested. Methods: We define DLCA as an approach to LCA which explicitly incorporates dynamic process modeling in the context of temporal and spatial variations in the surrounding industrial and environmental systems. A simplified mathematical model is used to incorporate dynamic information from the case study building, temporally explicit sources of life cycle inventory data and temporally explicit life cycle impact assessment characterization factors, where available. The DLCA model was evaluated for the historical and projected future environmental impacts of an existing institutional building, with additional scenario development for sensitivity and uncertainty analysis of future impacts. Results and discussion: Results showed that overall life cycle impacts varied greatly in some categories when compared to static LCA results, generated from the temporal perspective of either the building's initial construction or its recent renovation. From the initial construction perspective, impacts in categories related to criteria air pollutants were reduced by more than 50 % when compared to a static LCA, even though nonrenewable energy use increased by 15 %. Pollution controls were a major reason for these reductions. In the future scenario analysis, the baseline DLCA scenario showed a decrease in all impact categories compared with the static LCA. The outer bounds of the sensitivity analysis varied from slightly higher to strongly lower than the static results, indicating the general robustness of the decline across the scenarios. Conclusions: These findings support the use of dynamic modeling in life cycle assessment to increase the relevance of results. In some cases, decision making related to building design and operations may be affected by considering the interaction of temporally explicit information in multiple steps of the LCA. The DLCA results suggest that in some cases, changes during a building's lifetime can influence the LCA results to a greater degree than the material and construction phases. Adapting LCA to a more dynamic approach may increase the usefulness of the method in assessing the performance of buildings and other complex systems in the built environment. [ABSTRACT FROM AUTHOR]

In addition, the Author Contributions section now reads: Conceptualization, L.S., H.H. and C.S.D.P.; Formal analysis, L.S., H.H., R.A.C. and Z.Y.; Funding acquisition, C.S.D.P.; Methodology, L.S., H.H., Z.Y. and C.S.D.P.; Project administration, C.S.D.P.; Supervision, C.S.D.P.; Writing - original draft, L.S.; Writing - review & editing, L.S., H.H., R.A.C., Z.Y., S.C.P., R.A.B. and C.S.D.P. The original Article has been corrected. Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-022-08442-3, published online 16 March 2022 The original version of this Article contained an error in the spelling of the author Cintia S. de Paiva which was incorrectly given as Cintia de Paiva. [Extracted from the article]

Hybrid gas turbine–solid oxide fuel cell power generation has the potential to create a positive economic and environmental impact. Annually, the U.S. spends over $235 billion on electricity, and electric utilities emit 550 million metric tons of carbon. The integration of distributed hybrid generation can reduce these emissions and costs through increased efficiencies. In this paper, a model is presented that minimizes the costs of distributed hybrid generation while optimally locating the units within the existing electric infrastructure. The model utilizes data from hybrid generation modules, and includes uncertainty in customer demand, weather, and fuel costs. [ABSTRACT FROM AUTHOR]

Presents a study that examined the activation of signal transducer and activator of transcription (Stat) in glioma and medulloblastoma tumors. Background on Stat; Factors affecting the activation of Stat; Role of Stat in aberrant proliferation; Information on glioblastoma multiforme.

In Drosophila, the erect wing (ewg) protein is required for proper development of the central nervous system and the indirect flight muscles. The fly ewg gene encodes a novel DNA-binding domain that is also found in four genes previously identified in sea urchin, chicken, zebrafish, and human. To identify mouse ewg homologs, we designed degenerate primers to the conserved DNA-binding domain. The RT-PCR product obtained from mRNA of the mouse muscle cell line C2C12 was used to screen cDNA libraries; a single gene was identified which encodes a predicted 503 amino acid protein. The mouse ewg homolog, termed Nrf1, was mapped to proximal Chr 6. By RT-PCR and Northern analysis, Nrf1 was expressed in all tissues examined, and Northern analysis on adult tissues revealed a complex banding pattern suggesting extensive alternative splicing. Nrf1 hybridized to mRNA transcripts at approximately 2.2 kb, 4.0 kb, 4.4 kb, and 5.0 kb, with additional tissue-specific transcripts at 1.5 kb in testis, 1.9 kb in lung, and 3.7 kb in skeletal muscle. In situ hybridization on whole-mount E9–10.5 embryos showed a broad pattern of expression, with the highest levels of expression in the central nervous system, somites, first branchial arch, optic vesicle, and otic vesicle. [ABSTRACT FROM AUTHOR]

Gliomas are the most common primary malignant brain tumours and are classified into four clinical grades, with the most aggressive tumours being grade 4 astrocytomas (also known as glioblastoma multiforme; GBM). Frequent genetic alterations in GBMs (refs 2-5) result in stimulation of common signal transduction pathways involving Ras, Akt and other proteins. It is not known which of these pathways, if any, are sufficient to induce GBM formation. Here we transfer, in a tissue-specific manner, genes encoding activated forms of Ras and Akt to astrocytes and neural progenitors in mice. We found that although neither activated Ras nor Akt alone is sufficient to induce GBM formation, the combination of activated Ras and Akt induces highgrade gliomas with the histological features of human GBMs. These tumours appear to arise after gene transfer to neural progenitors, but not after transfer to differentiated astrocytes. Increased activity of RAS is found in many human GBMs (ref. 11), and we show here that Akt activity is increased in most of these tumours, implying that combined activation of these two pathways accurately models the biology of this disease. [ABSTRACT FROM AUTHOR]

Oral treatment with probiotic bacteria has been shown to prevent bone loss in multiple models of osteoporosis. In previous studies we demonstrated that oral administration of Lactobacillus reuteri in healthy male mice increases bone density. The host and bacterial mechanisms of these effects however are not well understood. The objective of this study was to understand the role of lymphocytes in mediating the beneficial effects of L. reuteri on bone health in male mice. We administered L. reuteri in drinking water for 4 weeks to wild type or Rag knockout (lack mature T and B lymphocytes) male mice. While L. reuteri treatment increased bone density in wild type, no significant increases were seen in Rag knockout mice, suggesting that lymphocytes are critical for mediating the beneficial effects of L. reuteri on bone density. To understand the effect of L. reuteri on lymphocytes in the intestinal tissues, we isolated mesenteric lymph node (MLN) from naïve wild type mice. In ex vivo studies using whole mesenteric lymph node (MLN) as well as CD3+ T-cells, we demonstrate that live L. reuteri and its secreted factors have concentration-dependent effects on the expression of cytokines, including anti-inflammatory cytokine IL-10. Fractionation studies identified that the active component of L. reuteri is likely water soluble and small in size (<3 kDa) and its effects on lymphocytes are negatively regulated by a RIP2 inhibitor, suggesting a role for NOD signaling. Finally, we show that T-cells from MLNs treated with L. reuteri supernatants, secrete factors that enhance osterix (transcription factor involved in osteoblast differentiation) expression in MC3T3-E1 osteoblasts. Together, these data suggest that L. reuteri secreted factors regulate T-lymphocytes which play an important role in mediating the beneficial effects of L. reuteri on bone density. [ABSTRACT FROM AUTHOR]

Previous research has shown that electrical muscle activity is able to synchronize between muscles of one subject. The ability to synchronize the mechanical muscle oscillations measured by Mechanomyography (MMG) is not described sufficiently. Likewise, the behavior of myofascial oscillations was not considered yet during muscular interaction of two human subjects. The purpose of this study is to investigate the myofascial oscillations intra- and interpersonally. For this the mechanical muscle oscillations of the triceps and the abdominal external oblique muscles were measured by MMG and the triceps tendon was measured by mechanotendography (MTG) during isometric interaction of two subjects (n = 20) performed at 80% of the MVC using their arm extensors. The coherence of MMG/MTG-signals was analyzed with coherence wavelet transform and was compared with randomly matched signal pairs. Each signal pairing shows significant coherent behavior. Averagely, the coherent phases of n = 485 real pairings last over 82 ± 39 % of the total duration time of the isometric interaction. Coherent phases of randomly matched signal pairs take 21 ± 12 % of the total duration time (n = 39). The difference between real vs. randomly matched pairs is significant (U = 113.0, p = 0.000, r = 0.73). The results show that the neuromuscular system seems to be able to synchronize to another neuromuscular system during muscular interaction and generate a coherent behavior of the mechanical muscular oscillations. Potential explanatory approaches are discussed. [ABSTRACT FROM AUTHOR]

A correction to the article "Dynamic Life Cycle Assessment: Framework and Application to an Institutional Building" that was published online on January 23, 2013, is presented.