bluuebunny/crossref_metadata_2025 huggingface dataset:
Formation of Amphibole‐Bearing Peridotite and Amphibole‐Bearing Pyroxenite Through Hydrous Melt‐Peridotite Reaction and In Situ Crystallization: An Experimental Study
Authors: Wang Chunguang , Liang Yan , Xu Wenliang
Published: January 2021

Amphibole is a common hydrous mineral in mantle rocks. To better understand processes leading to the formation of amphibole‐bearing peridotites and pyroxenites in the lithospheric mantle, we conducted experiments by juxtaposing a lherzolite against hydrous basaltic melts in Au‐Pd capsules. Two melts were examined, a basaltic andesite and a basalt, each containing 4 wt% of water. The experiments were run at 1200°C and 1 GPa for 3 or 12 h, and then cooled to 880°C and 0.8 GPa over 49 h. The reaction at 1200°C produced a melt‐bearing orthopyroxenite‐dunite sequence. Crystallization of the partially reacted melts during cooling lead to the formation of an amphibole‐bearing gabbronorite‐orthopyroxenite‐peridotite sequence. Orthopyroxene in the peridotite and orthopyroxenite has a poikilitic texture enclosing olivines and spinels. Amphibole in the peridotite occurs interstitial to olivine, orthopyroxene, clinopyroxene, and spinel. Comparisons of texture and mineral compositions in the experimental products with those from field observations allow a better understanding of hydrous melt‐rock reaction in the lithospheric mantle. Amphibole‐bearing pyroxenite veins (or dikes) can be formed in the lithospheric mantle or at the crust‐mantle boundary by interaction between hydrous melt and peridotite and subsequent crystallization. Hornblendite or amphibole gabbronorite can be formed in the veins when the flux of hydrous melt is high. Differences in reacting melt and peridotite compositions are responsible for the variation in amphibole composition in mantle xenoliths from different tectonic settings. The extent of melt‐rock reaction is a factor that control amphibole composition across the amphibole‐bearing vein and the host peridotite.
Remote Control of Filchner‐Ronne Ice Shelf Melt Rates by the Antarctic Slope Current
Authors: Bull Christopher Y. S. , Jenkins Adrian , Jourdain Nicolas C. , Vaňková Irena , Holland Paul R. , Mathiot Pierre , Hausmann Ute , Sallée Jean‐Baptiste
Published: January 2021

Recent work on the Filchner‐Ronne Ice Shelf (FRIS) system has shown that a redirection of the coastal current in the southeastern Weddell Sea could lead to a regime change in which an intrusion of warm Modified Circumpolar Deep Water results in large increases in the basal melt rate. Work to date has mostly focused on how increases in the Modified Circumpolar Deep Water crossing the continental shelf break leads directly to heat driven changes in melting in the ice‐shelf cavity. In this study, we introduce a Weddell Sea regional ocean model configuration with static ice shelves. We evaluate a reference simulation against radar observations of melting, and find good agreement between the simulated and observed mean melt rates. We analyze 28 sensitivity experiments that simulate the influence of changes in remote water properties of the Antarctic Slope Current on basal melting in the FRIS. We find that remote changes in salinity quasi‐linearly modulate the mean FRIS net melt rate. Changes in remote temperature quadratically vary the FRIS net melt rate. In both salinity and temperature perturbations, the response is rapid and transient, with a recovery time‐scale of 5–15 years dependent on the size/type of perturbation. We show that the two types of perturbations lead to different changes on the continental shelf, and that ultimately different factors modulate the melt rates in the FRIS cavity. We discuss how these results, are relevant for ocean hindcast simulations, sea level, and melt rate projections of the FRIS.
Volume Transport Variability on the Northern Argentine Continental Shelf From In Situ and Satellite Altimetry Data
Authors: Lago L. S. , Saraceno M. , Piola A. R. , Ruiz‐Etcheverry L. A.
Published: January 2021

Direct current observations and satellite altimetry data over the northern portion of the Argentine continental shelf are used to produce an 11‐month long hourly time series and a 25‐year long daily time series of along‐shore volume transport, respectively. At time scales longer than 20 days, the temporal variability of the in situ transport is significantly correlated with the transport inferred from satellite altimetry (r = 0.74). The mean in situ along‐shore transport is 2.65 ± 0.07 Sv (1 Sv = 106 m3 s−1) to the northeast and presents large variability, with a peak‐to‐peak range of 16 Sv. The extended satellite transport presents variability at multiple time scales. The annual cycle is the dominant signal, with a maximum during the austral autumn and a minimum during the austral spring. The interannual component of the transport is significantly correlated (r = −0.5) with the Southern Annular Mode (SAM). SAM‐induced along‐shore wind stress anomalies over the region modulate the cross‐shore pressure gradient that, in turn, modulates the along‐shore transport variability. This mechanism holds also at synoptic scales, highlighting the dominant role of the wind on the along‐shore transport. Satellite altimetry measurements also indicate that the cross‐shore pressure gradient generated by the variability of the Malvinas Current affects the along‐shore transport only in the outer 30 km of the continental shelf.
Impact of Different Nesting Methods on the Simulation of a Severe Convective Event Over South Korea Using the Weather Research and Forecasting Model
Authors: Madhulatha A. , Choi Suk‐Jin , Han Ji‐Young , Hong Song‐You
Published: January 2021

In this study, the effects of different nesting methods on simulating a flash‐flood‐producing severe convective event over Cheongju, South Korea on July 16, 2017 was examined. This event developed as part of a mesoscale convective system (MCS) accompanied by frontal forcing. Numerical experiments were conducted using the Weather Research and Forecasting model (WRF) employing one‐way concurrent (OWC), one‐way sequential (OWS), and two‐way (TW) nesting approaches with advanced physics options from Korean Integrated Model (KIM). Analysis of model simulations against Tropical Rainfall Measuring Mission (TRMM) and Automatic Weather Station (AWS) observations suggests that the TW nesting method performs better than both OW nesting methods in simulating rainfall. Large‐scale features, moisture, instability in the boundary layer, and the vertical distribution of meteorological parameters favorable for convection are better represented by TW nesting. Probability distribution Function (PDF) analysis from AWS/WRF reveals that the local‐scale distribution of surface meteorological parameters which affect storm intensity were well captured using TW. Further assessment of Equitable Threat score (ETS) also showed better precipitation forecast skill over different thresholds in TW. Vertical velocity in the innermost domain simulated using TW nesting is more consistent with ERA5 reanalysis. An additional MCS (11–13 July 2006) simulated using a similar numerical setup also benefited from TW nesting, increasing confidence in the initial findings. Along with frequent lateral boundary conditions, TW nesting allows multi‐scale interactions between parent and nested domains and improves the representation of both synoptic and local‐scale features, enhanced cloud hydrometeor, vertical velocity distributions, and subsequent rainfall.
Simulated Dust Transport in the Convective Boundary Layer
Authors: Cornwell Gavin C. , Xiao Heng , Berg Larry K. , Burrows Susannah M.
Published: January 2021

Soil dusts are an important source of aerosol in agricultural regions and can affect the Earth's radiation budget through the modification of cloud properties, and in particular, through their ability to act as ice nucleating particles. In order to impact cloud properties, agricultural soil dusts need to be transported from the point of emission to cloud‐relevant altitudes. Vertical transport within the planetary boundary layer is strongly controlled by turbulence and is challenging to represent accurately in regional and global models. Large‐eddy simulations (LES) are run at resolutions capable of resolving most of the turbulent energy directly and can thus better simulate vertical transport. In this study, we leverage the LES ARM Symbiotic Simulation and Observation (LASSO) large‐eddy simulations to simulate vertical transport of agricultural dust within the turbulent boundary layer using a modified version of the stochastic dispersion model FLEXPART‐WRF. We find that the modified model is better capable of simulating particle transport due to turbulence, and that particle size was the greatest factor in determining particle lifetime. Individual meteorology and particle density had intermediate effects upon particle transport, while release height had little effect upon simulation results. Finally, we utilize a quasi‐single column model (QSCM) approach to determine how our results compare to a parameterized treatment of turbulence. The QSCM simulations led to greater tracer transport out of the boundary layer, with ramifications for any studies utilizing a Lagrangian stochastic model to understand tracer dispersion. These results highlight the importance of accurately simulating turbulence for understanding particle transport.
Global Impact of Cloud Longwave Scattering in an Atmosphere‐Only General Circulation Model Simulation
Authors: Gu Boyan , Ren Tong , Kuo Chia‐Pang , Yang Ping , Bowman Kenneth
Published: January 2021

Most general circulation models (GCMs) neglect cloud longwave scattering in pursuit of computational efficiency. This study implements the 2‐/4‐stream (2/4S) method, a relatively fast cloud longwave scattering treatment, in Community Atmospheric Model version 5 (CAM5) to analyze the impact of cloud longwave scattering on the large‐scale circulation. Two 45‐years‐long integrations are performed with prescribed sea surface temperature (SST). In the experiment run, cloud longwave scattering is included using the 2/4S method; in the control run, clouds only absorb in the longwave. The results show that cloud longwave scattering acts to enhance the cloud longwave (greenhouse) effect by reducing outgoing longwave radiation (OLR) and enhancing downward longwave irradiance at the surface. The OLR reduction is most significant over the tropics, where surface temperatures and cloud elevations are high. The surface downward irradiance increase is most significant over polar areas and the Tibetan Plateau, where cloud elevations are low and the air below clouds is dry. Inclusion of cloud longwave scattering enhances the Walker circulation, suggestive of the importance of diabatic radiative heating in the tropical circulation. Inclusion of cloud longwave scattering also appears to shift the eddy‐driven jet poleward in the austral summer in the Southern Hemisphere, suggesting that the cloud longwave effect plays a role in shaping the jet position. Persistent equatorward jet biases in GCMs may be reduced if cloud longwave scattering is considered.
A Culinary Silver Lining of Climate Change: More Truffles
Authors: Kornei Katherine
Published: January 2021

The cultivation potential of a popular truffle species will increase in central Europe by 2050, global climate models predict.
Band-structure-engineered high-gain LWIR photodetector based on a type-II superlattice
Authors: Dehzangi Arash , Li Jiakai , Razeghi Manijeh
Published: January 2021

The LWIR and longer wavelength regions are of particular interest for new developments and new approaches to realizing long-wavelength infrared (LWIR) photodetectors with high detectivity and high responsivity. These photodetectors are highly desirable for applications such as infrared earth science and astronomy, remote sensing, optical communication, and thermal and medical imaging. Here, we report the design, growth, and characterization of a high-gain band-structure-engineered LWIR heterojunction phototransistor based on type-II superlattices. The 1/e cut-off wavelength of the device is 8.0 µm. At 77 K, unity optical gain occurs at a 90 mV applied bias with a dark current density of 3.2 × 10−7 A/cm2. The optical gain of the device at 77 K saturates at a value of 276 at an applied bias of 220 mV. This saturation corresponds to a responsivity of 1284 A/W and a specific detectivity of 2.34 × 1013 cm Hz1/2/W at a peak detection wavelength of ~6.8 µm. The type-II superlattice-based high-gain LWIR device shows the possibility of designing the high-performance gain-based LWIR photodetectors by implementing the band structure engineering approach.
Effect of time restricted eating on body weight and fasting glucose in participants with obesity: results of a randomized, controlled, virtual clinical trial
Authors: Peeke Pamela M. , Greenway Frank L. , Billes Sonja K. , Zhang Dachuan , Fujioka Ken
Published: January 2021

Background

Time restricted eating (TRE) is an emerging dietary intervention for weight loss that is hypothesized to reinforce the metabolic benefits of nightly fasting/ketosis. This pilot study investigated the effectiveness of a daily 14-h metabolic fast (14:10 TRE beginning after dinner, a “fasting snack” at hour 12, and ending with breakfast 14 h later) combined with a commercial weight management program on body weight and fasting blood glucose (FBG) in individuals with obesity. We also investigated the effect of the low-calorie, high-fat, low-carbohydrate, and low-protein “fasting snack” on blood glucose.

Methods

This 8-week, randomized, controlled, clinical trial included men and women (BMI ≥ 30 kg/m2) between June and October 2020. Study procedures were conducted remotely. Participants were randomized to 14:10 or 12-h TRE (12:12, active comparator) and prescribed a diet (controlled for calories and macronutrient composition) and exercise program that included weekly customized counseling and support. The primary outcome was change from baseline in body weight in the 14:10 group.

Results

Of the 78 randomized participants, 60 (n = 30/group) completed 8 weeks. The LS mean change from baseline in weight in the 14:10 group was −8.5% (95% CI −9.6 to −7.4;P < 0.001) and −7.1% (−8.3 to −5.8;P < 0.001) in the 12:12 group (between group difference −1.4%; −2.7 to −0.2;P < 0.05). There was a statistically significant LS mean change from baseline to week 8 in FBG in the 14:10 group of −7.6 mg/dl (95% CI −15.1 to −0.1;P < 0.05) but not in the 12:12 group (−3.1 mg/dl, −10.0 to 3.7;P = NS). Both interventions resulted in a larger reduction in FBG in participants with elevated FBG (≥100 mg/dl) at baseline (bothP < 0.05).

Conclusions

In participants with obesity who completed 8 weeks of the 14:10 TRE schedule combined with a commercial weight loss program, there was statistically significant and clinically meaningful weight loss and improvements in FBG.
Prolactin receptor-driven combined luminal and epithelial differentiation in breast cancer restricts plasticity, stemness, tumorigenesis and metastasis
Authors: Shams Anwar , Binothman Najat , Boudreault Julien , Wang Ni , Shams Fuad , Hamam Dana , Tian Jun , Moamer Alaa , Dai Meiou , Lebrun Jean-Jacques , Ali Suhad
Published: January 2021

Dedifferentiation increased cellular plasticity and stemness are established derivers of tumor heterogeneity, metastasis and therapeutic failure resulting in incurable cancers. Therefore, it is essential to decipher pro/forward-differentiation mechanisms in cancer that may serve as therapeutic targets. We found that interfering with expression of the receptor for the lactogenic hormone prolactin (PRLR) in breast cancer cells representative of the luminal and epithelial breast cancer subtypes (hormone receptor positive (HR+) and HER2-enriched (HER2-E) resulted in loss of their differentiation state, enriched for stem-like cell subpopulations, and increased their tumorigenic capacity in a subtype-specific manner. Loss of PRLR expression in HR+ breast cancer cells caused their dedifferentiation generating a mesenchymal-basal-like phenotype enriched in CD44+ breast cancer stem-like cells (BCSCs) showing high tumorigenic and metastatic capacities and resistance to anti-hormonal therapy. Whereas loss of PRLR expression in HER2-E breast cancer cells resulted in loss of their luminal differentiation yet enriched for epithelial ALDH+ BCSC population showing elevated HER2-driven tumorigenic, multi-organ metastatic spread, and resistance to anti-HER2 therapy. Collectively, this study defines PRLR as a driver of precise luminal and epithelial differentiation limiting cellular plasticity, stemness, and tumorigenesis and emphasizing the function of pro/forward-differentiation pathways as a foundation for the discovery of anti-cancer therapeutic targets.
Multimodal sensory evaluation of neuropathic spinal cord injury pain: an experimental study
Authors: Opsommer Emmanuelle , Korogod Natalya , Stockinger Lenka , Landmann Gunther
Published: January 2021

Study design

An experimental study.

Objectives

To investigate the changes in somatosensory functions using the combined application of quantitative sensory testing (QST), contact heat-evoked potentials (CHEPs) and laser-evoked potentials (LEPs) studies in individuals with spinal cord injury (SCI) in relation to neuropathic pain (NeP).

Setting

Centre for Pain Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland.

Methods

Individuals with SCI were compared: 12 with NeP (SCI NeP) and 12 without NeP (SCI no NeP). Tools used were QST, CHEPs, LEPs and self-reported questionnaires. Tests were applied to the control (hand) and test (dermatome of altered sensation) sites, and compared to the able-bodied group.

Results

QST, LEPs and CHEPs assessments showed abnormalities both on the test and control sites, which did not differ between the groups with SCI. QST showed higher prevalence of allodynia in SCI NeP. CHEPs and LEPs demonstrated diminished amplitudes in both groups with SCI in comparison to able-bodied individuals. Only reaction time (RT) analysis revealed the difference of SCI NeP from the other two groups, expressed in partially preserved responses to the laser C-fibre stimulations.

Conclusions

Combination of assessments in our study allowed to examine spinothalamic and dorsal column functions in individuals with SCI. Changes in QST, CHEPs and LEPs were detected below the level of injury independent of NeP and at the control site indicating modifications in sensory processing rostral to the spinal lesion. Analysis of RT during laser stimulation could be an essential component when evaluating the somatosensory functions related to NeP in persons with SCI.
Comparative genomics reveals new functional insights in uncultured MAST species
Authors: Labarre Aurelie , López-Escardó David , Latorre Francisco , Leonard Guy , Bucchini François , Obiol Aleix , Cruaud Corinne , Sieracki Michael E , Jaillon Olivier , Wincker Patrick , Vandepoele Klaas , Logares Ramiro , Massana Ramon
Published: January 2021

Heterotrophic lineages of stramenopiles exhibit enormous diversity in morphology, lifestyle, and habitat. Among them, the marine stramenopiles (MASTs) represent numerous independent lineages that are only known from environmental sequences retrieved from marine samples. The core energy metabolism characterizing these unicellular eukaryotes is poorly understood. Here, we used single-cell genomics to retrieve, annotate, and compare the genomes of 15 MAST species, obtained by coassembling sequences from 140 individual cells sampled from the marine surface plankton. Functional annotations from their gene repertoires are compatible with all of them being phagocytotic. The unique presence of rhodopsin genes in MAST species, together with their widespread expression in oceanic waters, supports the idea that MASTs may be capable of using sunlight to thrive in the photic ocean. Additional subsets of genes used in phagocytosis, such as proton pumps for vacuole acidification and peptidases for prey digestion, did not reveal particular trends in MAST genomes as compared with nonphagocytotic stramenopiles, except a larger presence and diversity of V-PPase genes. Our analysis reflects the complexity of phagocytosis machinery in microbial eukaryotes, which contrasts with the well-defined set of genes for photosynthesis. These new genomic data provide the essential framework to study ecophysiology of uncultured species and to gain better understanding of the function of rhodopsins and related carotenoids in stramenopiles.
Newly discovered Asgard archaea Hermodarchaeota potentially degrade alkanes and aromatics via alkyl/benzyl-succinate synthase and benzoyl-CoA pathway
Authors: Zhang Jia-Wei , Dong Hong-Po , Hou Li-Jun , Liu Yang , Ou Ya-Fei , Zheng Yan-Ling , Han Ping , Liang Xia , Yin Guo-Yu , Wu Dian-Ming , Liu Min , Li Meng
Published: January 2021

Asgard archaea are widely distributed in anaerobic environments. Previous studies revealed the potential capability of Asgard archaea to utilize various organic substrates including proteins, carbohydrates, fatty acids, amino acids and hydrocarbons, suggesting that Asgard archaea play an important role in sediment carbon cycling. Here, we describe a previously unrecognized archaeal phylum, Hermodarchaeota, affiliated with the Asgard superphylum. The genomes of these archaea were recovered from metagenomes generated from mangrove sediments, and were found to encode alkyl/benzyl-succinate synthases and their activating enzymes that are similar to those identified in alkane-degrading sulfate-reducing bacteria. Hermodarchaeota also encode enzymes potentially involved in alkyl-coenzyme A and benzoyl-coenzyme A oxidation, the Wood–Ljungdahl pathway and nitrate reduction. These results indicate that members of this phylum have the potential to strictly anaerobically degrade alkanes and aromatic compounds, coupling the reduction of nitrate. By screening Sequence Read Archive, additional genes encoding 16S rRNA and alkyl/benzyl-succinate synthases analogous to those in Hermodarchaeota were identified in metagenomic datasets from a wide range of marine and freshwater sediments. These findings suggest that Asgard archaea capable of degrading alkanes and aromatics via formation of alkyl/benzyl-substituted succinates are ubiquitous in sediments.
Light stimulates anoxic and oligotrophic growth of glacial Flavobacterium strains that produce zeaxanthin
Authors: Liu Qing , Li Wei , Liu Di , Li Lingyan , Li Jie , Lv Na , Liu Fei , Zhu Baoli , Zhou Yuguang , Xin Yuhua , Dong Xiuzhu
Published: January 2021

Bacteria that inhabit glaciers usually produce carotenoids. Here, we report that a group of zeaxanthin-producing glacial Flavobacterium exhibited light-promoted growth. Of the tested 47 strains, 45 showed increased growths but two died under illumination at 50 μmol photon m−2 s−1. Light stimulation occurred mainly in either anoxic or nutrient-poor cultures, while the same levels of light promotion were found for that grown at 14 and 7 °C. Pigment assays identified overrepresentative zeaxanthin but trace retinal in the light promoted 45 strains, while flexirubin was exclusively in the light-lethal two. Genomic analysis revealed the gene cluster for zeaxanthin synthesis in the 45 strains, in which 37 strains also harbored the proteorhodopsin gene prd. Transcriptomic analysis found that light-induced expressions of both the zeaxanthin synthesis and proteorhodopsin genes. Whereas, deletion of the prd gene in one strain did not diminish light promotion, inhibition of zeaxanthin synthesis did. In comparison, no light promotion was determined in a glacier Cryobacterium luteum that produced a non-zeaxanthin-type carotenoid. Therefore, light stimulation on the glacial Flavobacterium is mostly likely related to zeaxanthin, which could provide better photoprotection and sustain membrane integrity for the organisms living in cold environments.
A cortical immune network map identifies distinct microglial transcriptional programs associated with β-amyloid and Tau pathologies
Authors: Patrick Ellis , Olah Marta , Taga Mariko , Klein Hans-Ulrich , Xu Jishu , White Charles C. , Felsky Daniel , Agrawal Sonal , Gaiteri Chris , Chibnik Lori B. , Mostafavi Sara , Schneider Julie A. , Bennett David A. , Bradshaw Elizabeth M. , De Jager Philip L.
Published: January 2021

Microglial dysfunction has been proposed as one of the many cellular mechanisms that can contribute to the development of Alzheimer’s disease (AD). Here, using a transcriptional network map of the human frontal cortex, we identify five modules of co-expressed genes related to microglia and assess their role in the neuropathologic features of AD in 540 subjects from two cohort studies of brain aging. Two of these transcriptional programs—modules 113 and 114—relate to the accumulation of β-amyloid, while module 5 relates to tau pathology. We replicate these associations in brain epigenomic data and in two independent datasets. In terms of tau, we propose that module 5, a marker of activated microglia, may lead to tau accumulation and subsequent cognitive decline. We validate our model further by showing that three representative module 5 genes (ACADVL, TRABD, and VASP) encode proteins that are upregulated in activated microglia in AD.
Weighted gene coexpression network and experimental analyses identify lncRNA SPRR2C as a regulator of the IL-22-stimulated HaCaT cell phenotype through the miR-330/STAT1/S100A7 axis
Authors: Luo Meijunzi , Huang Pan , Pan Yi , Zhu Zhu , Zhou Rong , Yang Zhibo , Wang Chang
Published: January 2021

Psoriasis is a chronic inflammatory disease of the skin with highly complex pathogenesis. In this study, we identified lncRNA SPRR2C (small proline-rich protein 2C) as a hub gene with a critical effect on the pathogenesis of psoriasis and response to treatment using both weighted gene coexpression network analysis (WGCNA) and differential expression analysis. SPRR2C expression was significantly upregulated in both psoriatic lesion samples and HaCaT cell lines in response to IL-22 treatment. After SPRR2C knockdown, IL-22-induced suppression of HaCaT proliferation, changes in the KRT5/14/1/10 protein levels, and suppression of the IL-1β, IL-6, and TNF-α mRNA levels were dramatically reversed. In the coexpression network with SPRR2C based on GSE114286, miR-330 was significantly negatively correlated with SPRR2C, while STAT1 and S100A7 were positively correlated with SPRR2C. By binding to miR-330, SPRR2C competed with STAT1 and S100A7 to counteract miR-330-mediated suppression of STAT1 and S100A7. MiR-330 overexpression also reversed the IL-22-induced changes in HaCaT cell lines; in response to IL-22 treatment, miR-330 inhibition significantly attenuated the effects of SPRR2C knockdown. STAT1 and S100A7 expression was significantly upregulated in psoriatic lesion samples. The expression of miR-330 had a negative correlation with the expression of SPRR2C, while the expression of SPRR2C had a positive correlation with the expression of STAT1 and S100A7. Thus, SPRR2C modulates the IL-22-stimulated HaCaT cell phenotype through the miR-330/STAT1/S100A7 axis. WGCNA might uncover additional biological pathways that are crucial in the pathogenesis and response to the treatment of psoriasis.
Transneuronal delivery of hyper-interleukin-6 enables functional recovery after severe spinal cord injury in mice
Authors: Leibinger Marco , Zeitler Charlotte , Gobrecht Philipp , Andreadaki Anastasia , Gisselmann Günter , Fischer Dietmar
Published: January 2021

Spinal cord injury (SCI) often causes severe and permanent disabilities due to the regenerative failure of severed axons. Here we report significant locomotor recovery of both hindlimbs after a complete spinal cord crush. This is achieved by the unilateral transduction of cortical motoneurons with an AAV expressing hyper-IL-6 (hIL-6), a potent designer cytokine stimulating JAK/STAT3 signaling and axon regeneration. We find collaterals of these AAV-transduced motoneurons projecting to serotonergic neurons in both sides of the raphe nuclei. Hence, the transduction of cortical neurons facilitates the axonal transport and release of hIL-6 at innervated neurons in the brain stem. Therefore, this transneuronal delivery of hIL-6 promotes the regeneration of corticospinal and raphespinal fibers after injury, with the latter being essential for hIL-6-induced functional recovery. Thus, transneuronal delivery enables regenerative stimulation of neurons in the deep brain stem that are otherwise challenging to access, yet highly relevant for functional recovery after SCI.
Rhythmic glucose metabolism regulates the redox circadian clockwork in human red blood cells
Authors: Ch Ratnasekhar , Rey Guillaume , Ray Sandipan , Jha Pawan K. , Driscoll Paul C. , Dos Santos Mariana Silva , Malik Dania M. , Lach Radoslaw , Weljie Aalim M. , MacRae James I. , Valekunja Utham K. , Reddy Akhilesh B.
Published: January 2021

Circadian clocks coordinate mammalian behavior and physiology enabling organisms to anticipate 24-hour cycles. Transcription-translation feedback loops are thought to drive these clocks in most of mammalian cells. However, red blood cells (RBCs), which do not contain a nucleus, and cannot perform transcription or translation, nonetheless exhibit circadian redox rhythms. Here we show human RBCs display circadian regulation of glucose metabolism, which is required to sustain daily redox oscillations. We found daily rhythms of metabolite levels and flux through glycolysis and the pentose phosphate pathway (PPP). We show that inhibition of critical enzymes in either pathway abolished 24-hour rhythms in metabolic flux and redox oscillations, and determined that metabolic oscillations are necessary for redox rhythmicity. Furthermore, metabolic flux rhythms also occur in nucleated cells, and persist when the core transcriptional circadian clockwork is absent in Bmal1 knockouts. Thus, we propose that rhythmic glucose metabolism is an integral process in circadian rhythms.
The human endogenous attentional control network includes a ventro-temporal cortical node
Authors: Sani Ilaria , Stemmann Heiko , Caron Bradley , Bullock Daniel , Stemmler Torsten , Fahle Manfred , Pestilli Franco , Freiwald Winrich A.
Published: January 2021

Endogenous attention is the cognitive function that selects the relevant pieces of sensory information to achieve goals and it is known to be controlled by dorsal fronto-parietal brain areas. Here we expand this notion by identifying a control attention area located in the temporal lobe. By combining a demanding behavioral paradigm with functional neuroimaging and diffusion tractography, we show that like fronto-parietal attentional areas, the human posterior inferotemporal cortex exhibits significant attentional modulatory activity. This area is functionally distinct from surrounding cortical areas, and is directly connected to parietal and frontal attentional regions. These results show that attentional control spans three cortical lobes and overarches large distances through fiber pathways that run orthogonally to the dominant anterior-posterior axes of sensory processing, thus suggesting a different organizing principle for cognitive control.
Massively parallel cantilever-free atomic force microscopy
Authors: Cao Wenhan , Alsharif Nourin , Huang Zhongjie , White Alice E. , Wang YuHuang , Brown Keith A.
Published: January 2021

Resolution and field-of-view often represent a fundamental tradeoff in microscopy. Atomic force microscopy (AFM), in which a cantilevered probe deflects under the influence of local forces as it scans across a substrate, is a key example of this tradeoff with high resolution imaging being largely limited to small areas. Despite the tremendous impact of AFM in fields including materials science, biology, and surface science, the limitation in imaging area has remained a key barrier to studying samples with intricate hierarchical structure. Here, we show that massively parallel AFM with >1000 probes is possible through the combination of a cantilever-free probe architecture and a scalable optical method for detecting probe–sample contact. Specifically, optically reflective conical probes on a comparatively compliant film are found to comprise a distributed optical lever that translates probe motion into an optical signal that provides sub-10 nm vertical precision. The scalability of this approach makes it well suited for imaging applications that require high resolution over large areas.
Plasmons in the van der Waals charge-density-wave material 2H-TaSe2
Authors: Song Chaoyu , Yuan Xiang , Huang Ce , Huang Shenyang , Xing Qiaoxia , Wang Chong , Zhang Cheng , Xie Yuangang , Lei Yuchen , Wang Fanjie , Mu Lei , Zhang Jiasheng , Xiu Faxian , Yan Hugen
Published: January 2021

Plasmons in two-dimensional (2D) materials beyond graphene have recently gained much attention. However, the experimental investigation is limited due to the lack of suitable materials. Here, we experimentally demonstrate localized plasmons in a correlated 2D charge-density-wave (CDW) material: 2H-TaSe2. The plasmon resonance can cover a broad spectral range from the terahertz (40 μm) to the telecom (1.55 μm) region, which is further tunable by changing thickness and dielectric environments. The plasmon dispersion flattens at large wave vectors, resulted from the universal screening effect of interband transitions. More interestingly, anomalous temperature dependence of plasmon resonances associated with CDW excitations is observed. In the CDW phase, the plasmon peak close to the CDW excitation frequency becomes wider and asymmetric, mimicking two coupled oscillators. Our study not only reveals the universal role of the intrinsic screening on 2D plasmons, but also opens an avenue for tunable plasmons in 2D correlated materials.
Publisher Correction: Unveiling the strong interaction among hadrons at the LHC
Authors:   ALICE Collaboration
Published: January 2021

A Correction to this paper has been published: https://doi.org/10.1038/s41586-020-03142-2.
Single-neuron dynamical effects of dendritic pruning implicated in aging and neurodegeneration: towards a measure of neuronal reserve
Authors: Kirch Christoph , Gollo Leonardo L.
Published: January 2021

Aging is a main risk factor for neurodegenerative disorders including Alzheimer's disease. It is often accompanied by reduced cognitive functions, gray-matter volume, and dendritic integrity. Although age-related brain structural changes have been observed across multiple scales, their functional implications remain largely unknown. Here we simulate the aging effects on neuronal morphology as dendritic pruning and characterize its dynamical implications. Utilizing a detailed computational modeling approach, we simulate the dynamics of digitally reconstructed neurons obtained from Neuromorpho.org. We show that dendritic pruning affects neuronal integrity: firing rate is reduced, causing a reduction in energy consumption, energy efficiency, and dynamic range. Pruned neurons require less energy but their function is often impaired, which can explain the diminished ability to distinguish between similar experiences (pattern separation) in older people. Our measures indicate that the resilience of neuronal dynamics is neuron-specific, heterogeneous, and strongly affected by dendritic topology and the position of the soma. Based on the emergent neuronal dynamics, we propose to classify the effects of dendritic deterioration, and put forward a topological measure of “neuronal reserve” that quantifies the resilience of neuronal dynamics to dendritic pruning. Moreover, our findings suggest that increasing dendritic excitability could partially mitigate the dynamical effects of aging.
Ultra-purification of Lipopolysaccharides reveals species-specific signalling bias of TLR4: importance in macrophage function
Authors: Stephens Matthew , Liao Shan , von der Weid Pierre-Yves
Published: January 2021

TLR4 location, and bacterial species-derived lipopolysaccharides, play a significant role in the downstream activation of transcription factors, accessory molecules, and products. Here, this is demonstrated through the use of classically-activated and alternatively-activated macrophages. We show that, when polarized, human macrophages differentially express and localize TLR4, resulting in biased recognition and subsequent signalling of LPS derived from Pseudomonas aeruginosa, Escherichia coli, and Salmonella enterica. Analysis of activation demonstrated that in classically activated macrophages, P. aeruginosa signals from the plasma membrane via TLR4 to p65 dependent on TAK1 and TBK1 signalling. E. coli signals dependent or independent of the endosome, utilizing both TAK1- and TBK1-signalling to induce P65 and IRF3 inducible genes and cytokines. S. enterica however, only induces P65 and IRF3 phosphorylation through signalling via the endosome. This finding outlines clear signalling mechanisms by which innate immune cells, such as macrophages, can distinguish between bacterial species and initiate specialized responses through TLR4.
Test–retest reliability of laser evoked pain perception and fMRI BOLD responses
Authors: Bi Yanzhi , Hou Xin , Zhong Jiahui , Hu Li
Published: January 2021

Pain perception is a subjective experience and highly variable across time. Brain responses evoked by nociceptive stimuli are highly associated with pain perception and also showed considerable variability. To date, the test–retest reliability of laser-evoked pain perception and its associated brain responses across sessions remain unclear. Here, an experiment with a within-subject repeated-measures design was performed in 22 healthy volunteers. Radiant-heat laser stimuli were delivered on subjects’ left-hand dorsum in two sessions separated by 1–5 days. We observed that laser-evoked pain perception was significantly declined across sessions, coupled with decreased brain responses in the bilateral primary somatosensory cortex (S1), right primary motor cortex, supplementary motor area, and middle cingulate cortex. Intraclass correlation coefficients between the two sessions showed “fair” to “moderate” test–retest reliability for pain perception and brain responses. Additionally, we observed lower resting-state brain activity in the right S1 and lower resting-state functional connectivity between right S1 and dorsolateral prefrontal cortex in the second session than the first session. Altogether, being possibly influenced by changes of baseline mental state, laser-evoked pain perception and brain responses showed considerable across-session variability. This phenomenon should be considered when designing experiments for laboratory studies and evaluating pain abnormalities in clinical practice.
Sustainable production of camptothecin from an Alternaria sp. isolated from Nothapodytes nimmoniana
Authors: Mohinudeen I. A. H. Khwajah , Kanumuri Rahul , Soujanya K. N. , Shaanker R. Uma , Rayala Suresh Kumar , Srivastava Smita
Published: January 2021

Camptothecin the third most in demand alkaloid, is commercially extracted in India from the endangered plant, Nothapodytes nimmoniana. Endophytes, the microorganisms that reside within plants, are reported to have the ability to produce host–plant associated metabolites. Hence, our research aims to establish a sustainable and high camptothecin yielding endophyte, as an alternative source for commercial production of camptothecin. A total of 132 endophytic fungal strains were isolated from different plant parts (leaf, petiole, stem and bark) of N. nimmoniana, out of which 94 were found to produce camptothecin in suspension culture. Alternaria alstroemeriae (NCIM1408) and Alternaria burnsii (NCIM1409) demonstrated camptothecin yields up to 426.7 ± 33.6 µg/g DW and 403.3 ± 41.6 µg/g DW, respectively, the highest reported production to date. Unlike the reported product yield attenuation in endophytes with subculture in axenic state, Alternaria burnsii NCIM1409 could retain and sustain the production of camptothecin up to ~ 200 μg/g even after 12 continuous subculture cycles. The camptothecin biosynthesis in Alternaria burnsii NCIM1409 was confirmed using 13C carbon labelling (and cytotoxicity analysis on different cancer cell lines) and this strain can now be used to develop a sustainable bioprocess for in vitro production of camptothecin as an alternative to plant extraction.
Unusual derivatives from Hypericum scabrum
Authors: Soroury Sara , Alilou Mostafa , Gelbrich Thomas , Tabefam Marzieh , Danton Ombeline , Ebrahimi Samad N. , Kaiser Marcel , Hamburger Matthias , Stuppner Hermann , Moridi Farimani Mahdi
Published: January 2021

Three new compounds (1–3) with unusual skeletons were isolated from the n-hexane extract of the air-dried aerial parts of Hypericum scabrum. Compound 1 represents the first example of an esterified polycyclic polyprenylated acylphloroglucinol that features a unique tricyclo-[4.3.1.11,4]-undecane skeleton. Compound 2 is a fairly simple MPAP, but with an unexpected cycloheptane ring decorated with prenyl substituents, and compound 3 has an unusual 5,5-spiroketal lactone core. Their structures were determined by extensive spectroscopic and spectrometric techniques (1D and 2D NMR, HRESI-TOFMS). Absolute configurations were established by ECD calculations, and the absolute structure of 2 was confirmed by a single crystal determination. Plausible biogenetic pathways of compounds 1–3 were also proposed. The in vitro antiprotozoal activity of the compounds against Trypanosoma brucei rhodesiense and Plasmodium falciparum and cytotoxicity against rat myoblast (L6) cells were determined. Compound 1 showed a moderate activity against T. brucei and P. falciparum, with IC50 values of 3.07 and 2.25 μM, respectively.
Leg amputation modifies coordinated activation of the middle leg muscles in the cricket Gryllus bimaculatus
Authors: Owaki Dai , Aonuma Hitoshi , Sugimoto Yasuhiro , Ishiguro Akio
Published: January 2021

Insects alter their walking pattern in order to respond to demands of an ever-changing environment, such as varying ground surface textures. They also exhibit resilient and flexible ability to retain the capacity to walk even after substantial changes in their body properties, e.g. leg amputation. While the motor control paradigm governing the inter-leg coordination in such adaptive walking has been extensively described in past studies, the mechanism remains unknown. Here, we examined this question by using the cricket (Gryllus bimaculatus), which shows a tetrapod/tripod gait on a flat surfaces, like many other insects. We performed leg amputation experiments to investigate modifications of leg movements and coordination of muscle activities. We simultaneously recorded (1) the leg movements, locomotion velocity, and body rotation and (2) the leg movements and leg muscles activities before and after leg amputation. Crickets displayed adaptive coordination of leg movement patterns in response to amputations. The activation timings of levator muscles in both middle legs tended to synchronize in phase when both legs were amputated at the coxatrochanteral joint. This supports the hypothesis that an intrinsic contralateral connection within the mesothoracic ganglion exists, and that mechanosensory feedback from the legs override this connection, resulting in the anti-phase movement of a normal gait.
A system dynamics model for pests and natural enemies interactions
Authors: Sokame Bonoukpoè Mawuko , Tonnang Henri E. Z. , Subramanian Sevgan , Bruce Anani Y. , Dubois Thomas , Ekesi Sunday , Calatayud Paul-André
Published: January 2021

Stemborers (Busseola fusca, Sesamia calamistis and Chilo partellus), the fall armyworm (Spodoptera frugiperda) and associated parasitoids constitute an interacting system in maize fields in Kenya. This work aims at developing and evaluating models that represent the evolution of those interactions by applying system thinking and system dynamics approaches with its archetypes [causal loop diagram (CLD), reinforcing (R) and balancing (B)] to analyse the population of these multi-species systems. The software Vensim PLE 8.0.9 was used to implement the models and carry out the simulations of single- and multi-species systems. The results showed that when a single pest species with its associated parasitoids interact with the host plant, the species was able to establish and sustain by cyclical relationship between populations of the pest and the associated parasitoids. However, in multi- pest species systems, dominance of S. frugiperda and C. partellus over B. fusca and S. calamistis was observed, but without extinction. However, there was a likelihood for B. fusca being displaced by C. partellus. Overall, the models predict the co-existence of fall armyworm with stemborer species as an additional pest of maize in Africa that need to be considered henceforth in designing IPM strategies in maize.
Shared and unique metabolic features of the malignant and benign thyroid lesions determined with use of 1H HR MAS NMR spectroscopy
Authors: Skorupa Agnieszka , Ciszek Mateusz , Chmielik Ewa , Boguszewicz Łukasz , Oczko-Wojciechowska Małgorzata , Kowalska Małgorzata , Rusinek Dagmara , Tyszkiewicz Tomasz , Kluczewska-Gałka Aneta , Czarniecka Agnieszka , Jarząb Barbara , Sokół Maria
Published: January 2021

The purpose of this work was to investigate the distinct and common metabolic features of the malignant and benign thyroid lesions in reference to the non-transformed tissue from the contralateral gland (chronic thyroiditis and colloid goiter). 1H HR MAS NMR spectra of 38 malignant lesions, 32 benign lesions and 112 samples from the non-tumoral tissue (32 from chronic thyroiditis and 80 samples from colloid goiter) were subjected both to multivariate and univariate analysis. The increased succinate, glutamine, glutathione, serine/cysteine, ascorbate, lactate, taurine, threonine, glycine, phosphocholine/glycerophosphocholine and decreased lipids were found in both lesion types in comparison to either colloid goiter or chronic thyroiditis. The elevated glutamate and choline, and reduced citrate and glucose were additionally evident in these lesions in reference to goiter, while the increased myo-inositol—in comparison to thyroiditis. The malignant lesions were characterized by the higher alanine and lysine levels than colloid goiter and thyroiditis, while scyllo-inositol was uniquely increased in the benign lesions (not in cancer) in comparison to both non-tumoral tissue types. Moreover, the benign lesions presented with the unique increase of choline in reference to thyroiditis (not observed in the cancerous tissue). The metabolic heterogeneity of the non-tumoral tissue should be considered in the analysis of metabolic reprogramming in the thyroid lesions.
NT-PGC-1α deficiency attenuates high-fat diet-induced obesity by modulating food intake, fecal fat excretion and intestinal fat absorption
Authors: Kim Jihyun , Moon Jiyoung , Park Chul-Hong , Lee Jisu , Cheng Helia , Floyd Z. Elizabeth , Chang Ji Suk
Published: January 2021

Transcriptional coactivator PGC-1α and its splice variant NT-PGC-1α regulate metabolic adaptation by modulating many gene programs. Selective ablation of PGC-1α attenuates diet-induced obesity through enhancing fatty acid oxidation and thermogenesis by upregulation of NT-PGC-1α in brown adipose tissue (BAT). Recently, we have shown that selective ablation of NT-PGC-1α reduces fatty acid oxidation in BAT. Thus, the objective of this study was to test our hypothesis that NT-PGC-1α−/− mice would be more prone to diet-induced obesity. Male and female NT-PGC-1α+/+ (WT) and NT-PGC-1α−/− mice were fed a regular chow or 60% high-fat (HF) diet for 16 weeks. Contrary to our expectations, both male and female NT-PGC-1α−/− mice fed HFD were protected from diet-induced obesity, with more pronounced effects in females. This lean phenotype was primarily driven by reduced dietary fat intake. Intriguingly, HFD-fed female, but not male, NT-PGC-1α−/− mice further exhibited decreased feed efficiency, which was closely associated with increased fecal fat excretion and decreased uptake of fatty acids by the intestinal enterocytes and adipocytes with a concomitant decrease in fatty acid transporter gene expression. Collectively, our results highlight the role for NT-PGC-1α in regulating whole body lipid homeostasis under HFD conditions.