bluuebunny/crossref_metadata_2025 huggingface dataset:
The Pandemic and Gender Inequality in Academia
Authors: Kim Eunji , Patterson Shawn
Published: September 2021

Has the pandemic exacerbated gender inequality in academia? We provide real- time evidence by analyzing 1.8 million tweets from approximately 3,000 political scientists, leveraging their use of social media for career advancement. Using automated text analysis and difference-in-differences estimation, we find that although faculty members of both genders were affected by the pandemic, the shift to remote work caused women to tweet less often than their male colleagues about professional accomplishments. We argue that these effects are driven by the increased familial obligations placed on women, as demonstrated by the increase in family-related tweets and the more pronounced effects among junior academics. Our evidence demonstrating the gendered shift in professional visibility during the pandemic provides the opportunity for proactive efforts to address disparities that otherwise may take years to manifest.
Coproduction as Pedagogy: Harnessing Community Data Partnerships for the Classroom
Authors: Pudlo Jason M. , Ellis William C. , Cole Jamie M.
Published: September 2021

Increased computing capacity and the spread of computational knowledge has generated the expectation that organizations and municipalities use large quantities of data to drive decision making. However, municipalities may lack the resources to meaningfully use their data for decision making. Relatedly, political science and public administration programs face the challenge of training students for success in this environment. We believe one remedy is the adoption of coproduction as a pedagogical strategy. This article presents a case study of a partnership between a university research team and a municipal emergency communications center as a demonstration of how coproduction can be harnessed as a teaching tool. Findings from this project were presented at the Southern Political Science Association Annual Meeting, January 8–11, 2020, in San Juan, Puerto Rico.
FRIENDSHIP IS SKIN (COLOR) DEEP
Authors: Santana Emilce
Published: September 2021

Friendships between members of different ethnoracial groups can help to reduce prejudice and ease tensions across ethnoracial groups. A large body of literature has explored possible determinants for the formation of these friendships. One unexplored factor is the role of an individual’s skin color in influencing their opportunities to befriend members of other ethnoracial groups. This study seeks to answer two questions: For ethnoracial minorities, how is an individual’s skin color associated with the likelihood that they will engage in a cross-ethnoracial friendship? Does the role of skin color depend on the ethnoracial combination of the two groups that befriend one another? Using waves 1, 2, and 3 of the National Longitudinal Survey of Freshmen and a series of multinomial logit models, the results suggest that the role of skin color is a function of the relative levels of social status of the two ethnoracial groups that befriend one another. I argue that lighter-skinned members of lower status ethnoracial groups have a greater likelihood of having close friendships with members of higher status ethnoracial groups. There is also limited evidence that darker-skinned members of a higher status group, specifically Asians, have a greater likelihood of having close friends from a lower status group.
Potential wheat yield loss due to weeds in the United States and Canada
Authors: Flessner Michael L. , Burke Ian C. , Dille J. Anita , Everman Wesley J. , VanGessel Mark J. , Tidemann Breanne , Manuchehri Misha R. , Soltani Nader , Sikkema Peter H.
Published: September 2021

Yield losses due to weeds are a major threat to wheat production and economic well-being of farmers in the United States and Canada. The objective of this Weed Science Society of America (WSSA) Weed Loss Committee report is to provide estimates of wheat yield and economic losses due to weeds. Weed scientists provided both weedy (best management practices but no weed control practices) and weed-free (best management practices providing >90% weed control) average yield from replicated research trials in both winter and spring wheat from 2007 to 2017. Winter wheat yield loss estimates ranged from 2.9% to 34.4%, with a weighted average (by production) of 25.6% for the United States, 2.9% for Canada, and 23.4% combined. Based on these yield loss estimates and total production, the potential winter wheat loss due to weeds is 10.5, 0.09, and 10.5 billion kg with a potential loss in value of US$2.19, US$0.19, and US$2.19 billion for the United States, Canada, and combined, respectively. Spring wheat yield loss estimates ranged from 7.9% to 47.0%, with a weighted average (by production) of 33.2% for the United States, 8.0% for Canada, and 19.5% combined. Based on this yield loss estimate and total production, the potential spring wheat loss is 4.8, 1.6, and 6.6 billion kg with a potential loss in value of US$1.14, US$0.37, and US$1.39 billion for the United States, Canada, and combined, respectively. Yield loss in this analysis is greater than some previous estimates, likely indicating an increasing threat from weeds. Climate is affecting yield loss in winter wheat in the Pacific Northwest, with percent yield loss being highest in wheat-fallow systems that receive less than 30 cm of annual precipitation. Continued investment in weed science research for wheat is critical for continued yield protection.
Automatic Identification of Mantle Seismic Phases Using a Convolutional Neural Network
Authors: Garcia J. A. , Waszek L. , Tauzin B. , Schmerr N.
Published: September 2021

Typical seismic waveform data sets comprise hundreds of thousands to millions of records. Compilation is performed by time‐consuming handpicking of phase arrival times, or signal processing algorithms such as cross‐correlation. The latter generally underperform compared to handpicking. However, differences in picking methods creates variations in models and interpretation of Earth's structure. Here, we exploit the pattern recognition capabilities of Convolutional Neural Networks (CNN). Using a large handpicked data set, we train a CNN model to identify the seismic shear phase SS. This accelerates, automates, and makes consistent data compilation, a task usually completed by visual inspection and influenced by scientists' choices. The CNN model is employed to identify precursors to SS generated by mantle discontinuities. It identifies precursors in stacked and individual seismograms, producing new measurements of the mantle transition zone with quality comparable to handpicked data. This rapid acquisition of high‐quality observations has implications for automation of future seismic tomography studies.
Properties of the Recovery Phase of Extreme Storms
Authors: Choraghe Komal , Raghav Anil , Chakrabarty D. , Kasthurirangan S. , Bijewar N.
Published: September 2021

A geomagnetic storm is a phenomenon of weakening of Earth's magnetic field from a few hours to several days, which directly or indirectly affects navigation, transportation, communication, power grids, satellite electronics, etc. In general, the duration of the recovery phase is larger. Thus, its cumulative effect is greater than the main phase. Therefore, it is important to understand the physical processes involved during the recovery phase. In this paper, we have studied the recovery phase of 31 extreme geomagnetic storms that occurred from 1990 to 2020. Each storm demonstrates two distinct features of the recovery phase that is, initial fast and later slow recovery phase. During the fast recovery phase, the rate of recovery either linearly or non‐linearly depends on , which has been characterized by an exponential or hyperbolic decay function in various reported studies. In our study, we have noted that the hyperbolic function explains the complete recovery phase of only 11 extreme events. Furthermore, both decay functions fail to explain the late recovery phase of storms. Interestingly, we have found that the rate of recovery during the slow phase shows steady variation (independent to ), that is, . Our analysis suggests that the magnitude of the recovery rate during the late phase is proportional to the magnitude of the storm.
Transient Slow Slip Characteristics of Frictional‐Viscous Subduction Megathrust Shear Zones
Authors: Behr Whitney M. , Gerya Taras V. , Cannizzaro Claudio , Blass Robert
Published: September 2021

The deep roots of subduction megathrusts exhibit aseismic slow slip events, commonly accompanied by tectonic tremor. Observations from exhumed rocks suggest this region of the subduction interface is a shear zone with frictional lenses embedded in a viscous matrix. Here, we use numerical models to explore the transient slip characteristics of finite‐width frictional‐viscous megathrust shear zones. Our model utilizes an invariant, continuum‐based, regularized form of rate‐ and state‐dependent friction (RSF) and simulates earthquakes along spontaneously evolving faults embedded in a 2D heterogeneous continuum. The setup includes two elastic plates bounding a viscoelastoplastic shear zone (subduction interface melange) with inclusions (clasts) of varying distributions and viscosity contrasts with respect to the surrounding weaker matrix. The entire shear zone exhibits the same velocity‐weakening RSF parameters, but the lower viscosity matrix has the capacity to switch between RSF and viscous creep as a function of local stress state. Results demonstrate a mechanism in which stress heterogeneity in these shear zones both (a) sets the “speed limit” for earthquake ruptures that nucleate in clasts such that they propagate at slow velocities; and (b) permits the transmission of slow slip from clast to clast, allowing slow ruptures to propagate substantial distances over the model domain. For reasonable input parameters, modeled events have moment‐duration statistics, stress drops, and rupture propagation rates that overlap with some natural slow slip events. These results provide new insights into how geologic observations from ancient analogs of the slow slip source may scale up to match geophysical constraints on modern slow slip phenomena.
Turbulence Theory: Imperfect, but Necessary
Authors: Vallis Geoffrey K.
Published: September 2021

Key Points

Provides a scaling theory for baroclinic turbulence

Use a novel combination of vortex gas theory and theory of beta‐plane jets

Good agreement with the simulations presented
A Mélange of Subduction Ages: Constraints on the Timescale of Shear Zone Development and Underplating at the Subduction Interface, Catalina Schist (CA, USA)
Authors: Harvey K. M. , Walker S. , Starr P. G. , Penniston‐Dorland S. C. , Kohn M. J. , Baxter E. F.
Published: September 2021

The presence of mélange at the subduction interface influences numerous geochemical and geophysical processes. However, the relationship between the timescales of mélange development, deformation, and resultant mass transport is poorly understood. Here, we use Sm‐Nd garnet geochronology to elucidate the timing of peak metamorphism for five garnet amphibolite tectonic blocks from the amphibolite‐facies mélange zone of the Catalina Schist (Santa Catalina Island, CA). Ages range from 108 to 116 Ma and do not appear to correlate with the peak metamorphic temperature recorded by each block (between 640 and 740°C). The lack of correlation between age and peak temperature favors the tectonic mixing model previously proposed for the unit. These ages overlap with previous estimates of 111–114 Ma for peak metamorphism of the mélange zone but are predominately younger than an estimate for the structurally lower coherent amphibolite unit of ca. 115 Ma. White mica 40Ar/39Ar ages from previous studies suggest that the units cooled asynchronously to 400–425°C by 106 to 97 Ma at rates between 18 and 43°C/Ma. Collectively, these results demonstrate that mélange formation occurred over at least 8 Myr from 116 to 108 Ma and was followed by cooling. The structural and chronologic relationship between the mélange zone and underlying lower‐grade units indicates that the cooling occurred in conjunction with an underplating event between 109 and 108 Ma. The age discrepancy between the mélange zone and the underlying coherent amphibolite unit may indicate that the two units were juxtaposed either during or after the underplating event.
Carpathian‐Pannonian Magmatism Database
Authors: Vlasceanu Mihai , Ducea Mihai N. , Luffi Peter , Barla Anca , Seghedi Ioan
Published: September 2021

A database containing previously published geochronologic, geochemical, and isotopic data on Mesozoic to Quaternary igneous rocks from the Carpathian‐Pannonian region is presented. Georeferenced data making up this database belong mostly to rocks sampled from five magmatic arcs: (a) the South Apuseni Jurassic island arc/backarc province, (b) a small volume mid‐Cretaceous arc of the northernmost South Carpathians, (c) a late Cretaceous arc, locally known as “banatitic,” marking the closure of the Neotethys, (d) a regionally extensive Miocene ignimbrite flare‐up, and (e) the Miocene‐Quaternary collisional arc and associated extension‐related basalts of the Pannonian and Transylvanian basins. The database is anchored by location and ages of various igneous rocks, as well as geochemical and isotopic data, where available. The database is publicly available online (https://osf.io/23kdg/), as well as a Supporting Information S1 attached to this manuscript. We exemplify the utility of the database by calculating paleo crustal thicknesses in the Carpathians as a function of time using well‐calibrated geochemical paleo‐mohometers.
Decomposing the Oxygen Signal in the Ocean Interior: Beyond Decomposing Organic Matter
Authors: Cassar Nicolas , Nicholson David , Khatiwala Samar , Cliff Ellen
Published: September 2021

In the subsurface ocean, O2 depleted because of organic matter remineralization is generally estimated based on apparent oxygen utilization (AOU). However, AOU is an imperfect measure of oxygen utilization because of O2 air‐sea disequilibrium at the site of deepwater formation. Recent methodological and instrumental advances have paved the way to further deconvolve the processes driving the O2 signature. Using numerical model simulations of the global ocean, we show that the measurements of the dissolved O2/Ar ratio, which so far have been confined to the ocean surface, can provide improved estimates of oxygen utilization, especially in regions where the disequilibrium at the site of deepwater formation is associated with physical processes. We discuss applications of this new approach and implications for the current tracers relying on O2 such as remineralization ratios, respiratory quotients, and preformed nutrients. Finally, we propose a new composite geochemical tracer, combining dissolved O2/Ar and phosphate concentration. Being insensitive to photosynthesis and respiration, the change in this new tracer reflects gas exchange at the air‐sea interface at the sites of deepwater formation.
Future Weakening of the ENSO Ocean Carbon Buffer Under Anthropogenic Forcing
Authors: Liao Enhui , Resplandy Laure , Liu Junjie , Bowman Kevin W.
Published: September 2021

The El Niño Southern Oscillation (ENSO) is the largest driver of atmospheric CO2 interannual variability. The equatorial Pacific Ocean, which is a natural source of CO2 to the atmosphere, acts as a buffer of the terrestrial variations by releasing less CO2 during El Niño events and releasing more CO2 during La Niña events. Here, we examine how this ocean carbon buffer will respond to high anthropogenic emissions using Earth system models from Coupled Model Intercomparison Project Phase 6. The models project weaker ocean CO2 flux anomalies in the future due to two main factors: a stronger compensation between thermal and nonthermal changes in ocean biogeochemistry (55% of signal) and a weaker influence of ENSO on the CO2 transfer across the air‐sea interface (10%–25% of signal). The ocean would no longer buffer the land response to ENSO, and could even reinforce its impact on atmospheric CO2, amplifying the atmospheric carbon variability on interannual timescales.
A Stable H2O Atmosphere on Europa’s Trailing Hemisphere From HST Images
Authors: Roth Lorenz
Published: September 2021

Previous studies of the global intensities of the oxygen emissions at 1,356 Å and 1,304 Å revealed molecular oxygen (O2) in Europa's atmosphere. Here we investigate the relative changes of the two oxygen emissions when Europa emerges from eclipse as well as the radial profiles of the relative emissions across the sunlit disk in Hubble Space Telescope observations taken in 1999, 2012, 2014, and 2015 while the moon was at various orbital positions. The eclipse observation constrains the atomic oxygen (O) column density to or lower. We then find that the OI1356‐Å/OI1304‐Å ratio systematically decreases towards the disk center on the trailing hemisphere. The observed emission ratio pattern and the persistence of it from 1999 to 2015 imply a stable H2O abundance in the central sunlit trailing hemisphere with an H2O/O2 ratio of 12–22. On the leading hemisphere, the emissions are consistent with a pure O2 atmosphere everywhere across the moon disk.
First Observations of O2+ Band EMIC Waves in the Terrestrial Magnetosphere
Authors: Yu Xiongdong , Yuan Zhigang , Ouyang Zhihai
Published: September 2021

Although electromagnetic ion cyclotron (EMIC) waves are often known to exhibit three (H+, He+, and O+) usual bands, other peculiar minor ions (excluding He+ and O+) might also play an important role in the spectra of EMIC waves. This letter reports an interesting case that He+ band EMIC waves appear to split into O2+ and He+ band emissions. Wave frequency spectra suggesting that the organization of the wave emissions by the O2+ gyrofrequency motivates an investigation of the effects of O2+ presence on EMIC wave growth using linear theory. The calculated growth rates show that the original He+ band EMIC waves might be locally excited when O2+ is absent, while significant growth occurs for O2+ band and He+ band EMIC waves when O2+ is present. Our results provide insight into the generation of O2+ band EMIC waves.
Cloud Top Radiative Cooling Rate Drives Non‐Precipitating Stratiform Cloud Responses to Aerosol Concentration
Authors: Williams Abigail S. , Igel Adele L.
Published: September 2021

Increases in aerosol concentration are well known to influence the microphysical processes and radiative properties of clouds. By reducing droplet size, an increase in aerosol can lessen collision efficiency and increase liquid water path (LWP) in precipitating clouds or enhance evaporation rate and decrease LWP in non‐precipitating clouds. We utilize large eddy simulations to further investigate these aerosol indirect effects in Arctic mixed‐phase clouds and find, in agreement with previous studies, precipitating clouds to experience an increase in LWP and non‐precipitating clouds a decrease in LWP. Most importantly however, our results reveal a different explanation for why such an LWP decrease occurs in decoupled, non‐precipitating clouds. We find enhanced evaporation near cloud top to be driven primarily by a strengthening of maximum radiative cooling rate with aerosol concentration which drives stronger entrainment, an effect that holds true even in clouds that are optically thick.
Crustal Deformation and Detachment in the Sulu Orogenic Belt: New Constraints From Onshore‐Offshore Wide‐Angle Seismic Data
Authors: Liu Lihua , Hao Tianyao , Lu Chuanchuan , Wu Zhiqiang , Zheng Yanpeng , Wang Fuyun , Xu Ya , Kim Kwang‐hee , Kim Han‐joon
Published: September 2021

We deployed the first dense onshore‐offshore seismic survey profile across the ultrahigh/high‐pressure metamorphic Sulu Orogenic Belt (SLOB). By applying multiple seismic and gravity modeling, we obtained the crustal P wave velocity and density model across the SLOB and extending into tectonic units on both sides, including the eastern Sino‐Korean Block (SKB), and the lower Yangtze Block (YZB). A ∼120‐km‐wide high‐velocity and high‐density upper crust in the southern SLOB reveals the distribution of ultrahigh/high‐pressure metamorphism, which should be linking with the deep subduction, detachment, and exhumation of YZB midcrust. In the northern SLOB, the U‐shaped velocity contours throughout the crust and the low‐density midcrust reveals the downward bending of the crustal deformation due to the collision between SKB and YZB. The crustal deformation and detachment in the SLOB revealed by our results indicate that the orogenic spatial distribution should be wider than what we know before.
East Asian Summer Monsoon Rainfall Anomalies in 2020 and the Role of Northwest Pacific Anticyclone on the Intraseasonal‐to‐Interannual Timescales
Authors: Wang Xudong , Guan Zhaoyong , Jin Dachao , Zhu Jing
Published: September 2021

In summer 2020, extreme rainfall occurred over the middle and lower reaches of the Yangtze River Basin (YRB). The accumulated precipitation amount of this rainfall event broke the record since 1961. On the interannual timescale, seasonal mean rainfall anomalies in the YRB during summer 2020 are related to the tropical North Indian Ocean (NIO) sea surface temperature (SST) warming and a La Niña event in the equatorial eastern Pacific. Both the NIO SST warming and La Niña help to generate the anomalous tropospheric low‐level Northwest Pacific anticyclone (NWP‐AAC) via the Matsuno‐Gill type response. On the subseasonal timescale, rainfall anomalies in the YRB exhibit two significant periods during summer 2020, intraseasonal (40–60 days) and quasi‐biweekly (∼10 days). The former intraseasonal component is the focus of this study. The intraseasonal NWP‐AAC, which is a part of tropical intraseasonal oscillation, plays a dominant role in connecting the East Asian summer monsoon (EASM) rainfall with tropical convection. Using the pattern regression, a real‐time index (RTI) is proposed to represent the intraseasonal‐to‐interannual variability of the NWP‐AAC. The RTI captures the quasi‐biennial tendency of NWP‐AAC as well as its intraseasonal variability. These suggest that the NWP‐AAC is a common mode across timescales. Also, the RTI well depicts the EASM rainfall variability in 2020. Our results provide an alternative view of cross‐scale EASM variability, with an emphasis on the conduit effect of NWP‐AAC from intraseasonal to interannual timescale. Hence, the RTI could be utilized for subseasonal to seasonal climate monitoring in the Asian summer monsoon region.
Positron emission tomography imaging of serotonin degeneration and beta-amyloid deposition in late-life depression evaluated with multi-modal partial least squares
Authors: Smith Gwenn S. , Workman Clifford I. , Protas Hillary , Su Yi , Savonenko Alena , Kuwabara Hiroto , Gould Neda F. , Kraut Michael , Joo Jin Hui , Nandi Ayon , Avramopoulos Dimitri , Reiman Eric M. , Chen Kewei
Published: September 2021

Depression in late-life is associated with increased risk of cognitive decline and development of all-cause dementia. The neurobiology of late-life depression (LLD) may involve both neurochemical and neurodegenerative mechanisms that are common to depression and dementia. Transgenic amyloid mouse models show evidence of early degeneration of monoamine systems. Informed by these preclinical data, the hypotheses were tested that a spatial covariance pattern of higher beta-amyloid (Aβ) and lower serotonin transporter availability (5-HTT) in frontal, temporal, and parietal cortical regions would distinguish LLD patients from healthy controls and the expression of this pattern would be associated with greater depressive symptoms. Twenty un-medicated LLD patients who met DSM-V criteria for major depression and 20 healthy controls underwent PET imaging with radiotracers for Aβ ([11C]-PiB) and 5-HTT ([11C]-DASB). A voxel-based multi-modal partial least squares (mmPLS) algorithm was applied to the parametric PET images to determine the spatial covariance pattern between the two radiotracers. A spatial covariance pattern was identified, including higher Aβ in temporal, parietal and occipital cortices associated with lower 5-HTT in putamen, thalamus, amygdala, hippocampus and raphe nuclei (dorsal, medial and pontine), which distinguished LLD patients from controls. Greater expression of this pattern, reflected in summary 5-HTT/Aβ mmPLS subject scores, was associated with higher levels of depressive symptoms. The mmPLS method is a powerful approach to evaluate the synaptic changes associated with AD pathology. This spatial covariance pattern should be evaluated further to determine whether it represents a biological marker of antidepressant treatment response and/or cognitive decline in LLD patients.
Differential dopamine release by psychosis-generating and non-psychosis-generating addictive substances in the nucleus accumbens and dorsomedial striatum
Authors: Danielsson Klara , Stomberg Rosita , Adermark Louise , Ericson Mia , Söderpalm Bo
Published: September 2021

Schizophrenia is associated with three main categories of symptoms; positive, negative and cognitive. Of these, only the positive symptoms respond well to treatment with antipsychotics. Due to the lack of effect of antipsychotics on negative symptoms, it has been suggested that while the positive symptoms are related to a hyperdopaminergic state in associative striatum, the negative symptoms may be a result of a reduced dopamine (DA) activity in the nucleus accumbens (nAc). Drug abuse is common in schizophrenia, supposedly alleviating negative symptomatology. Some, but not all, drugs aggravate psychosis, tentatively due to differential effects on DA activity in striatal regions. Here this hypothesis was tested in rats by using a double-probe microdialysis technique to simultaneously assess DA release in the nAc and associative striatum (dorsomedial striatum; DMS) following administration of the psychosis-generating substances amphetamine (0.5 mg/kg), cocaine (15 mg/kg) and Δ9-tetrahydrocannabinol (THC, 3 mg/kg), and the generally non-psychosis-generating substances ethanol (2.5 g/kg), nicotine (0.36 mg/kg) and morphine (5 mg/kg). The data show that amphetamine and cocaine produce identical DA elevations both in the nAc and DMS, whereas nicotine increases DA in nAc only. Ethanol and morphine both increased DMS DA, but weaker and in a qualitatively different way than in nAc, suggesting that the manner in which DA is increased might be important to the triggering of psychosis. THC elevated DA in neither region, indicating that the pro-psychotic effects of THC are not related to DA release. We conclude that psychosis-generating substances affect striatal DA release differently than non-psychosis-generating substances.
“If I have teeth, I can smile.” Experiences with tooth loss and the use of a removable dental prosthesis among people who are partially and completely edentulous in Karnataka, India
Authors: Rodrigues Anisha , Dhanania Shradha , Rodrigues Rashmi
Published: September 2021

Objectives

Tooth loss is a phenomenon associated with structural and functional changes, with a negative influence on the oral and general health of an individual. Removable dental prosthesis is commonly fabricated as treatment for tooth loss. However, the perceptions and experiences of individuals during the transition from a dentate to a partially or completely edentulous state and their acceptance of the denture are largely ignored. The objective of this study was to explore the perceptions and experiences during the transition from a dentate state to being partially or completely edentulous in the Indian population.

Methods

Fifteen individuals wearing partial or complete denture prosthesis were interviewed in depth using open-ended questions. These interviews were recorded using a voice-recording device. They were then transcribed, and a coding process was applied using the thematic framework approach to qualitative analysis.

Findings

Five themes emerged, namely: (i) Transition from dentulous to partially or completely edentulous state; (ii) Varying experiences with the use of dentures; (iii) Convenience and duration of wearing dentures; (iv) Attitude of dentists towards patients’ complaints; (v) Knowledge and preference of available treatment modalities.

Conclusions

The loss of natural teeth seemed to affect the psychological, functional, and social well-being of participants. Tooth loss was believed to be a natural aging process. Costs of treatment deterred the uptake of fixed denture treatment options. However, some participants preferred removable dentures to fixed prosthesis.
Epo/EpoR signaling in osteoprogenitor cells is essential for bone homeostasis and Epo-induced bone loss
Authors: Rauner Martina , Murray Marta , Thiele Sylvia , Watts Deepika , Neumann Drorit , Gabet Yankel , Hofbauer Lorenz C. , Wielockx Ben
Published: September 2021

High erythropoietin (Epo) levels are detrimental to bone health in adult organisms. Adult mice receiving high doses of Epo lose bone mass due to suppressed bone formation and increased bone resorption. In humans, high serum Epo levels are linked to fractures in elderly men. Our earlier studies indicated that Epo modulates osteoblast activity; however, direct evidence that Epo acts via its receptor (EpoR) on osteoblasts in vivo is still missing. Here, we created mice lacking EpoR in osteoprogenitor cells to specifically address this gap. Deletion of EpoR in osteoprogenitors (EpoR:Osx-cre, cKO) starting at 5 weeks of age did not alter red blood cell parameters but increased vertebral bone volume by 25% in 12-week-old female mice. This was associated with low bone turnover. Histological (osteoblast number, bone formation rate) and serum (P1NP, osteocalcin) bone formation parameters were all reduced, as were the number of osteoclasts and TRAP serum level. Differentiation of osteoblast precursors isolated from cKO versus control mice resulted in lower expression of osteoblast marker genes including Runx2, Alp, and Col1a1 on day 21, whereas the mineralization capacity was similar. Moreover, the RANKL/OPG ratio, which determines the osteoclast-supporting potential of osteoblasts, was substantially decreased by 50%. Similarly, coculturing cKO osteoblasts with control or cKO osteoclast precursors produced significantly fewer osteoclasts than coculture with control osteoblasts. Finally, exposing female mice to Epo pumps (10 U·d−1) for 4 weeks resulted in trabecular bone loss (−25%) and increased osteoclast numbers (1.7-fold) in control mice only, not in cKO mice. Our data show that EpoR in osteoprogenitors is essential in regulating osteoblast function and osteoblast-mediated osteoclastogenesis via the RANKL/OPG axis. Thus, osteogenic Epo/EpoR signaling controls bone mass maintenance and contributes to Epo-induced bone loss.
Secretory products from epicardial adipose tissue induce adverse myocardial remodeling after myocardial infarction by promoting reactive oxygen species accumulation
Authors: Hao Shuang , Sui Xin , Wang Jing , Zhang Jingchao , Pei Yu , Guo Longhui , Liang Zhenxing
Published: September 2021

Adverse myocardial remodeling, manifesting pathologically as myocardial hypertrophy and fibrosis, often follows myocardial infarction (MI) and results in cardiac dysfunction. In this study, an obvious epicardial adipose tissue (EAT) was observed in the rat model of MI and the EAT weights were positively correlated with cardiomyocyte size and myocardial fibrosis areas in the MI 2- and 4-week groups. Then, rat cardiomyocyte cell line H9C2 and primary rat cardiac fibroblasts were cultured in conditioned media generated from EAT of rats in the MI 4-week group (EAT-CM). Functionally, EAT-CM enlarged the cell surface area of H9C2 cells and reinforced cardiac fibroblast activation into myofibroblasts by elevating intracellular reactive oxygen species (ROS) levels. Mechanistically, miR-134-5p was upregulated by EAT-CM in both H9C2 cells and primary rat cardiac fibroblasts. miR-134-5p knockdown promoted histone H3K14 acetylation of manganese superoxide dismutase and catalase by upregulating lysine acetyltransferase 7 expression, thereby decreasing ROS level. An in vivo study showed that miR-134-5p knockdown limited adverse myocardial remodeling in the rat model of MI, manifesting as alleviation of cardiomyocyte hypertrophy and fibrosis. In general, our study clarified a new pathological mechanism involving an EAT/miRNA axis that explains the adverse myocardial remodeling occurring after MI.
CXCL13/CXCR5 axis facilitates endothelial progenitor cell homing and angiogenesis during rheumatoid arthritis progression
Authors: Tsai Chun-Hao , Chen Chao-Ju , Gong Chi-Li , Liu Shan-Chi , Chen Po-Chun , Huang Chien-Chung , Hu Sung-Lin , Wang Shih-Wei , Tang Chih-Hsin
Published: September 2021

Angiogenesis is a critical process in the formation of new capillaries and a key participant in rheumatoid arthritis (RA) pathogenesis. The chemokine (C-X-C motif) ligand 13 (CXCL13) plays important roles in several cellular functions such as infiltration, migration, and motility. We report significantly higher levels of CXCL13 expression in collagen-induced arthritis (CIA) mice compared with controls and also in synovial fluid from RA patients compared with human osteoarthritis (OA) samples. RA synovial fluid increased endothelial progenitor cell (EPC) homing and angiogenesis, which was blocked by the CXCL13 antibody. By interacting with the CXCR5 receptor, CXCL13 facilitated vascular endothelial growth factor (VEGF) expression and angiogenesis in EPC through the PLC, MEK, and AP-1 signaling pathways. Importantly, infection with CXCL13 short hairpin RNA (shRNA) mitigated EPC homing and angiogenesis, articular swelling, and cartilage erosion in ankle joints of mice with CIA. CXCL13 is therefore a novel therapeutic target for RA.
Multi-platform profiling characterizes molecular subgroups and resistance networks in chronic lymphocytic leukemia
Authors: Bloehdorn Johannes , Braun Andrejs , Taylor-Weiner Amaro , Jebaraj Billy Michael Chelliah , Robrecht Sandra , Krzykalla Julia , Pan Heng , Giza Adam , Akylzhanova Gulnara , Holzmann Karlheinz , Scheffold Annika , Johnston Harvey E. , Yeh Ru-Fang , Klymenko Tetyana , Tausch Eugen , Eichhorst Barbara , Bullinger Lars , Fischer Kirsten , Weisser Martin , Robak Tadeusz , Schneider Christof , Gribben John , Dahal Lekh N. , Carter Mathew J. , Elemento Olivier , Landau Dan A. , Neuberg Donna S. , Cragg Mark S. , Benner Axel , Hallek Michael , Wu Catherine J. , Döhner Hartmut , Stilgenbauer Stephan , Mertens Daniel
Published: September 2021

Knowledge of the genomic landscape of chronic lymphocytic leukemia (CLL) grows increasingly detailed, providing challenges in contextualizing the accumulated information. To define the underlying networks, we here perform a multi-platform molecular characterization. We identify major subgroups characterized by genomic instability (GI) or activation of epithelial-mesenchymal-transition (EMT)-like programs, which subdivide into non-inflammatory and inflammatory subtypes. GI CLL exhibit disruption of genome integrity, DNA-damage response and are associated with mutagenesis mediated through activation-induced cytidine deaminase or defective mismatch repair. TP53 wild-type and mutated/deleted cases constitute a transcriptionally uniform entity in GI CLL and show similarly poor progression-free survival at relapse. EMT-like CLL exhibit high genomic stability, reduced benefit from the addition of rituximab and EMT-like differentiation is inhibited by induction of DNA damage. This work extends the perspective on CLL biology and risk categories in TP53 wild-type CLL. Furthermore, molecular targets identified within each subgroup provide opportunities for new treatment approaches.
Functional basis of electron transport within photosynthetic complex I
Authors: Richardson Katherine H. , Wright John J. , Šimėnas Mantas , Thiemann Jacqueline , Esteves Ana M. , McGuire Gemma , Myers William K. , Morton John J. L. , Hippler Michael , Nowaczyk Marc M. , Hanke Guy T. , Roessler Maxie M.
Published: September 2021

Photosynthesis and respiration rely upon a proton gradient to produce ATP. In photosynthesis, the Respiratory Complex I homologue, Photosynthetic Complex I (PS-CI) is proposed to couple ferredoxin oxidation and plastoquinone reduction to proton pumping across thylakoid membranes. However, little is known about the PS-CI molecular mechanism and attempts to understand its function have previously been frustrated by its large size and high lability. Here, we overcome these challenges by pushing the limits in sample size and spectroscopic sensitivity, to determine arguably the most important property of any electron transport enzyme – the reduction potentials of its cofactors, in this case the iron-sulphur clusters of PS-CI (N0, N1 and N2), and unambiguously assign them to the structure using double electron-electron resonance. We have thus determined the bioenergetics of the electron transfer relay and provide insight into the mechanism of PS-CI, laying the foundations for understanding of how this important bioenergetic complex functions.
Design and realization of topological Dirac fermions on a triangular lattice
Authors: Bauernfeind Maximilian , Erhardt Jonas , Eck Philipp , Thakur Pardeep K. , Gabel Judith , Lee Tien-Lin , Schäfer Jörg , Moser Simon , Di Sante Domenico , Claessen Ralph , Sangiovanni Giorgio
Published: September 2021

Large-gap quantum spin Hall insulators are promising materials for room-temperature applications based on Dirac fermions. Key to engineer the topologically non-trivial band ordering and sizable band gaps is strong spin-orbit interaction. Following Kane and Mele’s original suggestion, one approach is to synthesize monolayers of heavy atoms with honeycomb coordination accommodated on templates with hexagonal symmetry. Yet, in the majority of cases, this recipe leads to triangular lattices, typically hosting metals or trivial insulators. Here, we conceive and realize “indenene”, a triangular monolayer of indium on SiC exhibiting non-trivial valley physics driven by local spin-orbit coupling, which prevails over inversion-symmetry breaking terms. By means of tunneling microscopy of the 2D bulk we identify the quantum spin Hall phase of this triangular lattice and unveil how a hidden honeycomb connectivity emerges from interference patterns in Bloch px ± ipy-derived wave functions.
AI enabled sign language recognition and VR space bidirectional communication using triboelectric smart glove
Authors: Wen Feng , Zhang Zixuan , He Tianyiyi , Lee Chengkuo
Published: September 2021

Sign language recognition, especially the sentence recognition, is of great significance for lowering the communication barrier between the hearing/speech impaired and the non-signers. The general glove solutions, which are employed to detect motions of our dexterous hands, only achieve recognizing discrete single gestures (i.e., numbers, letters, or words) instead of sentences, far from satisfying the meet of the signers’ daily communication. Here, we propose an artificial intelligence enabled sign language recognition and communication system comprising sensing gloves, deep learning block, and virtual reality interface. Non-segmentation and segmentation assisted deep learning model achieves the recognition of 50 words and 20 sentences. Significantly, the segmentation approach splits entire sentence signals into word units. Then the deep learning model recognizes all word elements and reversely reconstructs and recognizes sentences. Furthermore, new/never-seen sentences created by new-order word elements recombination can be recognized with an average correct rate of 86.67%. Finally, the sign language recognition results are projected into virtual space and translated into text and audio, allowing the remote and bidirectional communication between signers and non-signers.
Selective deoxygenative alkylation of alcohols via photocatalytic domino radical fragmentations
Authors: Guo Hong-Mei , Wu Xuesong
Published: September 2021

The delivery of alkyl radicals through photocatalytic deoxygenation of primary alcohols under mild conditions is a so far unmet challenge. In this report, we present a one-pot strategy for deoxygenative Giese reaction of alcohols with electron-deficient alkenes, by using xanthate salts as alcohol-activating groups for radical generation under visible-light photoredox conditions in the presence of triphenylphosphine. The convenient generation of xanthate salts and high reactivity of sequential C–S/C–O bond homolytic cleavage enable efficient deoxygenation of primary, secondary and tertiary alcohols with diverse functionality and structure to generate the corresponding alkyl radicals, including methyl radical. Moreover, chemoselective radical monodeoxygenation of diols is achieved via selective formation of xanthate salts.
Impact of global cooling on Early Cretaceous high pCO2 world during the Weissert Event
Authors: Cavalheiro Liyenne , Wagner Thomas , Steinig Sebastian , Bottini Cinzia , Dummann Wolf , Esegbue Onoriode , Gambacorta Gabriele , Giraldo-Gómez Victor , Farnsworth Alexander , Flögel Sascha , Hofmann Peter , Lunt Daniel J. , Rethemeyer Janet , Torricelli Stefano , Erba Elisabetta
Published: September 2021

The Weissert Event ~133 million years ago marked a profound global cooling that punctuated the Early Cretaceous greenhouse. We present modelling, high-resolution bulk organic carbon isotopes and chronostratigraphically calibrated sea surface temperature (SSTs) based on an organic paleothermometer (the TEX86 proxy), which capture the Weissert Event in the semi-enclosed Weddell Sea basin, offshore Antarctica (paleolatitude ~54 °S; paleowater depth ~500 meters). We document a ~3–4 °C drop in SST coinciding with the Weissert cold end, and converge the Weddell Sea data, climate simulations and available worldwide multi-proxy based temperature data towards one unifying solution providing a best-fit between all lines of evidence. The outcome confirms a 3.0 °C ( ±1.7 °C) global mean surface cooling across the Weissert Event, which translates into a ~40% drop in atmospheric pCO2 over a period of ~700 thousand years. Consistent with geologic evidence, this pCO2 drop favoured the potential build-up of local polar ice.
CryoEM structure of the super-constricted two-start dynamin 1 filament
Authors: Liu Jiwei , Alvarez Frances Joan D. , Clare Daniel K. , Noel Jeffrey K. , Zhang Peijun
Published: September 2021

Dynamin belongs to the large GTPase superfamily, and mediates the fission of vesicles during endocytosis. Dynamin molecules are recruited to the neck of budding vesicles to assemble into a helical collar and to constrict the underlying membrane. Two helical forms were observed: the one-start helix in the constricted state and the two-start helix in the super-constricted state. Here we report the cryoEM structure of a super-constricted two-start dynamin 1 filament at 3.74 Å resolution. The two strands are joined by the conserved GTPase dimeric interface. In comparison with the one-start structure, a rotation around Hinge 1 is observed, essential for communicating the chemical power of the GTPase domain and the mechanical force of the Stalk and PH domain onto the underlying membrane. The Stalk interfaces are well conserved and serve as fulcrums for adapting to changing curvatures. Relative to one-start, small rotations per interface accumulate to bring a drastic change in the helical pitch. Elasticity theory rationalizes the diversity of dynamin helical symmetries and suggests corresponding functional significance.
Selective targeting of the TLR2/MyD88/NF-κB pathway reduces α-synuclein spreading in vitro and in vivo
Authors: Dutta Debashis , Jana Malabendu , Majumder Moumita , Mondal Susanta , Roy Avik , Pahan Kalipada
Published: September 2021

Pathways to control the spreading of α-synuclein (α-syn) and associated neuropathology in Parkinson’s disease (PD), multiple system atrophy (MSA) and dementia with Lewy bodies (DLB) are unclear. Here, we show that preformed α-syn fibrils (PFF) increase the association between TLR2 and MyD88, resulting in microglial activation. The TLR2-interaction domain of MyD88 (wtTIDM) peptide-mediated selective inhibition of TLR2 reduces PFF-induced microglial inflammation in vitro. In PFF-seeded A53T mice, the nasal administration of the wtTIDM peptide, NEMO-binding domain (wtNBD) peptide, or genetic deletion of TLR2 reduces glial inflammation, decreases α-syn spreading, and protects dopaminergic neurons by inhibiting NF-κB. In summary, α-syn spreading depends on the TLR2/MyD88/NF-κB pathway and it can be reduced by nasal delivery of wtTIDM and wtNBD peptides.
Tissue-agnostic drug approvals: how does this apply to patients with breast cancer?
Authors: Weis Luiza N. , Tolaney Sara M. , Barrios Carlos H. , Barroso-Sousa Romualdo
Published: September 2021

Precision medicine has provided new perspectives in oncology, yielding research on the use of targeted therapies across different tumor types, regardless of their site of origin, a concept known as tissue-agnostic indication. Since 2017, the Food and Drug Administration (FDA) has approved the use of three different agents for tumor-agnostic treatment: pembrolizumab (for patients with microsatellite instability or high tumor mutational burden) and larotrectinib and entrectinib (both for use in patients harboring tumors withNTRKfusions). Importantly, the genomic alterations targeted by these agents are uncommon or rare in breast cancer, and little information exists regarding their efficacy in advanced breast cancer. In this review, we discuss the prevalence of these targets in breast cancer, their detection methods, the clinical characteristics of patients whose tumors have these alterations, and available data regarding the efficacy of these agents in breast cancer.
Properties of poly (vinyl chloride) membranes containing cadmium pigments, irradiated with UV radiation
Authors: Tworek Magdalena , Skowroński Łukasz , Makarewicz Edwin , Kowalik Joanna
Published: September 2021

The cadmium pigments were yellow, orange and red pigments. They consisted of cadmium sulphide and cadmium sulphide with zinc sulphide as well as cadmium sulphide with cadmium selenide. Their quantitative composition and specific surface area were examined. The pigments were used to color the poly (vinyl chloride) plastisol films, which were then exposed to UV radiation. The surfaces of the coloured membranes were examined by infrared spectroscopy before and after irradiation with UV. The changes occurred in the PVC membrane were investigated by thermogravimetric analysis. The degree of crystallinity of the pigments and the membrane was determined by X-ray diffraction. The color change of the membranes was determined from the spectra obtained by reflection spectroscopy, and the components of colour L*, a* and b* were calculated. Base of them, the tolerance of colour deviations (ΔE*) was determined. The calculations allowed for the determination of the effect of UV irradiation on the change of the colour of the membranes and confirmation of the degradation of the pigments and polymer membrane.