bluuebunny/crossref_metadata_2025_split huggingface dataset:
Future Hot and Dry Years Worsen Nile Basin Water Scarcity Despite Projected Precipitation Increases
Authors: Coffel Ethan D. , Keith Bruce , Lesk Corey , Horton Radley M. , Bower Erica , Lee Jonathan , Mankin Justin S. 
Published: August 2019

AbstractCompound extremes—particularly hot and dry years—can reduce crop yields and result in acute water scarcity. These risks are particularly pronounced in the Upper Nile Basin, a chronically water stressed agricultural region that includes western Ethiopia, South Sudan, and Uganda. While the causes of humanitarian crises in the Nile Basin are complex and involve governance, conflict, and climate, we demonstrate that nearly all recent regional crop failures have occurred amid hot and dry conditions and low runoff supplies. Using an observational ensemble, we find that such hot and dry years have been more frequent in recent decades, driven by increasing regional temperatures. This trend is likely to continue despite climate model projections of increasing regional precipitation. By the late 21st century, the frequency of hot and dry years may rise by a factor of 1.5–3, even if warming is limited to 2 °C. Regional water scarcity will continue to be a chronic issue for the Upper Nile from population growth alone, but runoff deficits during future hot and dry years will amplify this effect, leaving an additional 5–15% of the future population facing water scarcity. Climate change, along with the region's complex water politics, dependence on subsistence agriculture, and history of geopolitical instability, places the region at risk of severe food and water shortages as hot and dry years become more frequent. Adaptation and climate‐resilient water management policies informed by an understanding of compound extremes will be essential to manage these risks.
Changes in the Dust‐Influenced Biological Carbon Pump in the Canary Current System: Implications From a Coastal and an Offshore Sediment Trap Record Off Cape Blanc, Mauritania
Authors: Fischer G. , Romero O. , Toby E. , Iversen M. , Donner B. , Mollenhauer G. , Nowald N. , Ruhland G. , Klann M. , Hamady B. , Wefer G. 
Published: August 2019

AbstractLong‐term data characterizing the oceans' biological carbon pump are essential for understanding impacts of climate variability on marine ecosystems. The “Bakun upwelling intensification hypothesis” suggests intensified coastal upwelling due to a greater land‐sea temperature gradient influenced by global warming. We present long time series of bathypelagic (approximately 1,200–3,600 m) particle fluxes from a coastal (CBeu: 2003–2016) and an offshore (CBmeso: 1988–2016) sediment trap setting located in the Canary Current upwelling. Organic carbon (Corg) and biogenic opal (BSi, diatoms) fluxes were twofold to threefold higher at the coastal upwelling site compared to the offshore site, respectively, and showed higher seasonality with flux maxima in spring. A relationship between winter and spring BSi fluxes to the North Atlantic Oscillation index was best expressed at the offshore site CBmeso. Lithogenic (dust) fluxes regularly peaked in winter when frequent low‐altitude dust storms and deposition occurred, decreasing offshore by about threefold. We obtained a high temporal match of short‐term peaks of BSi and dust fluxes in winter to spring at the inner site CBeu. We found synchronous flux variations at both sites and an anomalous year 2005, characterized by high BSi and Corg fluxes under a low North Atlantic Oscillation. Corg and BSi fluxes revealed a decreasing trend from 2006 to 2016 at the coastal site CBeu, pointing to coastal upwelling relaxation during the last two decades. The permanent offshore upwelling zone of the deflected Canary Current represented by the flux record of CBmeso showed no signs of increasing upwelling as well which contradicts the Bakun hypothesis.
Emersion of Distal Domains in Advanced Stages of Continental Rifting Explained by Asynchronous Crust and Mantle Necking
Authors: Chenin Pauline , Manatschal Gianreto , Decarlis Alessandro , Schmalholz Stefan M. , Duretz Thibault , Beltrando Marco 
Published: August 2019

AbstractWe propose an explanation to the enigmatic synrift erosional unconformities reported along the distal domain of several magma‐poor rifted margins. Using thermomechanical numerical modeling, we show that transient emersion of (future) distal domains following a phase of subsidence can be explained by asynchronous necking of first the upper mantle and subsequently the crust, without the need of prominent normal faulting caused by strain softening, mantle phase transitions, or magmatic processes. When the upper crust and upper mantle are mechanically decoupled by a weak lower crust and, in the absence of any prominent rheological heterogeneity, upper mantle, necking starts first because of the higher deviatoric stresses associated with its larger effective viscosity. Consequently, the ductile lower crustal material flows toward the necked mantle domain, delaying thinning of the overlying crust. Once the necked lithospheric mantle has locally lost most of its strength, the overdeepened Moho moves upward toward an isostatically compensated depth. This flexural rebound causes uplift and emersion of distal parts of the rift system that are composed of still relatively thick crust and triggers the necking of the overlying crust. Early necking of the upper mantle causes a transient heating event with temperatures up to 750 °C at the base of the crust in the (future) distal domain. The onset of this thermal event slightly predates emersion of the (future) distal domain. These results are consistent with field observations and thermochronological data from the fossil Alpine Tethys margins, as well as with seismic observations from several present‐day rifted margins.
On the Role of Reduced Air Density Along the Lightning Leader Path to Ground in Increasing X‐Ray Production Relative to Normal Atmospheric Conditions
Authors: Tran M. D. , Kereszy I. , Rakov V. A. , Dwyer J. R. 
Published: August 2019

AbstractMallick et al. (2012, https://doi.org/10.1029/2012JD017555) discovered that subsequent‐stroke leaders in natural negative lightning could be more prolific producers of hard X‐rays and gamma rays than the first‐stroke leader in the same flash. However, they had no optical records to confirm that their subsequent leaders followed the same path to ground as the first leader, as opposed to forging a new path to ground through cold air. In this paper, we present new observations, including optical data, showing that a second stroke produced more detectable X‐ray pulses than the first stroke, with both strokes following the same channel to ground. Additionally, we present data for the fifth stroke from a different flash, which show the occurrence of X‐ray emission at the onset of the common streamer zone between the hot channels of the downward negative dart‐stepped leader and upward positive connecting leader. However, there were no detectable X‐rays associated with negative leader steps.
The Modulation of Solar Wind Hydrogen Deposition in the Martian Atmosphere by Foreshock Phenomena
Authors: Fowler C. M. , Halekas J. , Schwartz S. , Goodrich K. A. , Gruesbeck J. R. , Benna M. 
Published: August 2019

AbstractThe neutral exosphere of Mars extends far upstream beyond the bow shock, and as a result, solar wind protons can charge exchange with this neutral exosphere to produce energetic neutral atoms. Energetic neutral atoms produced directly upstream of Mars will precipitate into the Martian dayside atmosphere, where some fraction can undergo a charge stripping reaction and can be observed as “penetrating protons.” Clear, quasiperiodic modulations in penetrating proton densities are observed during certain Mars Atmosphere and Volatile EvolutioN (MAVEN) periapsis passes, and we show that these modulations occur during radial interplanetary magnetic field conditions. During such times, the region sunward of Mars is defined by quasi‐parallel shock conditions, generating foreshock structures characterized by enhancements in magnetic field strength, enhancements in proton density, and deceleration and deflection of the solar wind flow. These structures are observed at time cadences equal to the modulation of penetrating proton densities at periapsis. Particle tracing simulations show that the convection of these structures with the solar wind leads to localized enhancements in the rate of charge exchange upstream of the shock, producing the observed temporal variations in penetrating proton densities at periapsis. The observation of modulated penetrating proton densities at periapsis can thus be used to infer the existence of radial interplanetary magnetic field conditions upstream of the bow shock at Mars at times when MAVEN does not sample the upstream solar wind.
Physical Drivers of Phytoplankton Bloom Initiation in the Southern Ocean's Scotia Sea
Authors: Prend Channing J. , Gille Sarah T. , Talley Lynne D. , Mitchell B. Greg , Rosso Isabella , Mazloff Matthew R. 
Published: August 2019

AbstractThe Scotia Sea is the site of one of the largest spring phytoplankton blooms in the Southern Ocean. Past studies suggest that shelf‐iron inputs are responsible for the high productivity in this region, but the physical mechanisms that initiate and sustain the bloom are not well understood. Analysis of profiling float data from 2002 to 2017 shows that the Scotia Sea has an unusually shallow mixed‐layer depth during the transition from winter to spring, allowing the region to support a bloom earlier in the season than elsewhere in the Antarctic Circumpolar Current. We compare these results to the mixed‐layer depth in the 1/6° data‐assimilating Southern Ocean State Estimate and then use the model output to assess the physical balances governing mixed‐layer variability in the region. Results indicate the importance of lateral advection of Weddell Sea surface waters in setting the stratification. A Lagrangian particle release experiment run backward in time suggests that Weddell outflow constitutes 10% of the waters in the upper 200 m of the water column in the bloom region. This dense Weddell water subducts below the surface waters in the Scotia Sea, establishing a sharp subsurface density contrast that cannot be overcome by wintertime convection. Profiling float trajectories are consistent with the formation of Taylor columns over the region's complex bathymetry, which may also contribute to the unique stratification. Furthermore, biogeochemical measurements from 2016 and 2017 bloom events suggest that vertical exchange associated with this Taylor column enhances productivity by delivering nutrients to the euphotic zone.
Phylogenetic, genomic, and biogeographic characterization of a novel and ubiquitous marine invertebrate-associated Rickettsiales parasite, Candidatus Aquarickettsia rohweri, gen. nov., sp. nov
Authors: Klinges J Grace , Rosales Stephanie M , McMinds Ryan , Shaver Elizabeth C , Shantz Andrew A , Peters Esther C , Eitel Michael , Wörheide Gert , Sharp Koty H , Burkepile Deron E , Silliman Brian R , Vega Thurber Rebecca L 
Published: August 2019

Abstract
Bacterial symbionts are integral to the health and homeostasis of invertebrate hosts. Notably, members of the Rickettsiales genus Wolbachia influence several aspects of the fitness and evolution of their terrestrial hosts, but few analogous partnerships have been found in marine systems. We report here the genome, phylogenetics, and biogeography of a ubiquitous and novel Rickettsiales species that primarily associates with marine organisms. We previously showed that this bacterium was found in scleractinian corals, responds to nutrient exposure, and is associated with reduced host growth and increased mortality. This bacterium, like other Rickettsiales, has a reduced genome indicative of a parasitic lifestyle. Phylogenetic analysis places this Rickettsiales within a new genus we define as “Candidatus Aquarickettsia.” Using data from the Earth Microbiome Project and SRA databases, we also demonstrate that members of “Ca. Aquarickettsia” are found globally in dozens of invertebrate lineages. The coral-associated “Candidatus A. rohweri” is the first finished genome in this new clade. “Ca. A. rohweri” lacks genes to synthesize most sugars and amino acids but possesses several genes linked to pathogenicity including Tlc, an antiporter that exchanges host ATP for ADP, and a complete Type IV secretion system. Despite its inability to metabolize nitrogen, “Ca. A. rohweri” possesses the NtrY-NtrX two-component system involved in sensing and responding to extracellular nitrogen. Given these data, along with visualization of the parasite in host tissues, we hypothesize that “Ca. A. rohweri” reduces coral health by consuming host nutrients and energy, thus weakening and eventually killing host cells. Last, we hypothesize that nutrient enrichment, which is increasingly common on coral reefs, encourages unrestricted growth of “Ca. A. rohweri” in its host by providing abundant N-rich metabolites to be scavenged.
Altered orbitofrontal sulcogyral patterns in gambling disorder: a multicenter study
Authors: Li Yansong , Wang Zixiang , Boileau Isabelle , Dreher Jean-Claude , Gelskov Sofie , Genauck Alexander , Joutsa Juho , Kaasinen Valtteri , Perales José C. , Romanczuk-Seiferth Nina , Ruiz de Lara Cristian M. , Siebner Hartwig R. , van Holst Ruth J. , van Timmeren Tim , Sescousse Guillaume 
Published: August 2019

AbstractGambling disorder is a serious psychiatric condition characterized by decision-making and reward processing impairments that are associated with dysfunctional brain activity in the orbitofrontal cortex (OFC). However, it remains unclear whether OFC functional abnormalities in gambling disorder are accompanied by structural abnormalities. We addressed this question by examining the organization of sulci and gyri in the OFC. This organization is in place very early and stable across life, such that OFC sulcogyral patterns (classified into Types I, II, and III) can be regarded as potential pre-morbid markers of pathological conditions. We gathered structural brain data from nine existing studies, reaching a total of 165 individuals with gambling disorder and 159 healthy controls. Our results, supported by both frequentist and Bayesian statistics, show that the distribution of OFC sulcogyral patterns is skewed in individuals with gambling disorder, with an increased prevalence of Type II pattern compared with healthy controls. Examination of gambling severity did not reveal any significant relationship between OFC sulcogyral patterns and disease severity. Altogether, our results provide evidence for a skewed distribution of OFC sulcogyral patterns in gambling disorder and suggest that pattern Type II might represent a pre-morbid structural brain marker of the disease. It will be important to investigate more closely the functional implications of these structural abnormalities in future work.
The effects of deep-brain non-stimulation in severe obsessive-compulsive disorder: an individual patient data meta-analysis
Authors: Schruers Koen , Baldi Samantha , van den Heuvel Tijl , Goossens Liesbet , Luyten Laura , Leentjens Albert. F. G. , Ackermans Linda , Temel Yasin , Viechtbauer Wolfgang 
Published: August 2019

AbstractNon-intervention-related effects have long been recognized in an array of medical interventions, to which surgical procedures like deep-brain stimulation are no exception. While the existence of placebo and micro-lesion effects has been convincingly demonstrated in DBS for major depression and Parkinson’s disease, systematic investigations for obsessive-compulsive disorder (OCD) are currently lacking. We therefore undertook an individual patient data meta-analysis with the aim of quantifying the effect of DBS for severe, treatment-resistant OCD that is not due to the electrical stimulation of brain tissue. The MEDLINE/PubMed database was searched for double-blind, sham-controlled randomized clinical trials published in English between 1998 and 2018. Individual patient data was obtained from the original authors and combined in a meta-analysis. We assessed differences from baseline in obsessive-compulsive symptoms following sham treatment, as measured by the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Four studies met the inclusion criteria, randomizing 49 patients to two periods of active or sham stimulation. To preclude confounding by period effects, our estimate was based only on data from those patients who underwent sham stimulation first (n = 24). We found that sham stimulation induced a significant change in the Y-BOCS score (t = −3.15, P < 0.005), lowering it by 4.9 ± 1.6 points [95% CI = (−8.0, –1.8)]. We conclude that non-stimulation-related effects of DBS exist also in OCD. The identification of the factors determining the magnitude and occurrence of these effects will help to design strategies that will ultimately lead to a betterment of future randomized clinical trials.
Association of elevated serumfree light chains with chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis
Authors: Clay-Gilmour Alyssa I. , Rishi Abdul R. , Goldin Lynn R. , Greenberg-Worisek Alexandra J. , Achenbach Sara J. , Rabe Kari G. , Maurer Matthew J. , Kay Neil E. , Shanafelt Tait D. , Call Timothy G. , Brice Weinberg J. , Camp Nicola J. , Cerhan James R. , Leis Jose , Norman Aaron , Murray David L. , Vincent Rajkumar S. , Caporaso Neil E. , Landgren Ola , McMaster Mary L. , Slager Susan L. , Vachon Celine M. 
Published: August 2019

AbstractChronic lymphocytic leukemia (CLL) and its precursor, monoclonal B-cell lymphocytosis (MBL), are heritable. Serumfree light-chain (sFLC) measures are a prognostic factor for CLL, but their role in susceptibility to CLL is not clear. We investigated differences between sFLC measurements in pre-treatment serum from five groups to inform the association of sFLC with familial and sporadic CLL: (1) familial CLL (n = 154), (2) sporadic CLL (n = 302), (3) familial MBL (n = 87), (4) unaffected first-degree relatives from CLL/MBL families (n = 263), and (5) reference population (n = 15,396). The percent of individuals having elevated monoclonal and polyclonal sFLCs was compared using age-stratified and age- and sex-adjusted logistic regression models. In age groups >50 years, monoclonal sFLC elevations were increased in sporadic and familial CLL cases compared to the reference population (p’s < 0.05). However, there were no statistically significant differences in sFLC monoclonal or polyclonal elevations between familial and sporadic CLL cases (p’s > 0.05). Unaffected relatives and MBL cases from CLL/MBL families, ages >60 years, showed elevated monoclonal sFLC, compared to the reference population (p’s < 0.05). This is the first study to demonstrate monoclonal sFLC elevations in CLL cases compared to controls. Monoclonal sFLC levels may provide additional risk information in relatives of CLL probands.
Inhibition of ZIP4 reverses epithelial-to-mesenchymal transition and enhances the radiosensitivity in human nasopharyngeal carcinoma cells
Authors: Zeng Qi , Liu Yi-min , Liu Jun , Han Jian , Guo Jian-xin , Lu Shun , Huang Xue-mei , Yi Ping , Lang Jin-yi , Zhang Peng , Wang Chun-ting 
Published: August 2019

AbstractZIP4 is a zinc transporter involved in epithelial cell morphology and migration in various cancers. In the epithelial-to-mesenchymal transition (EMT), epithelial cells transition into mesenchymal cells. The EMT plays a crucial role in invasiveness and metastasis during tumorigenesis. The aim of this study was to investigate the role of ZIP4 in the invasiveness and radiosensitivity of human nasopharyngeal carcinoma (NPC). In this study, results from 99 human patients with NPC showed that ZIP4 expression levels significantly correlated with a higher TN (tumor, lymph node) classification, as well as shorter overall survival (OS), recurrence-free survival (RFS), and distant metastasis-free survival (DMFS). Forced overexpression of ZIP4 promoted the migration and invasion of C666-1 cells through regulation of the EMT process. In contrast, ZIP4 silencing by lentivirus-mediated shRNA inhibited the EMT and metastasis of C666-1 cells in vitro and in vivo. Importantly, protein microarray analyses showed that downregulation of ZIP4 in C666-1 cells resulted in the decreased abundance of phosphoinositide 3-kinase (PI3K) p85 (Tyr607), phosphorylated (p)-Akt (Ser473), phosphorylated (p)-Akt (Thr308), and phosphorylated glycogen synthase kinase 3β (pGSK3β; Ser9). These data suggest that ZIP4 induces the EMT and promotes migration and invasion via the PI3K/Akt signaling pathway in NPC. Moreover, ZIP4 silencing significantly enhanced radiation-induced apoptosis and growth inhibition of human C666-1 cells in vitro and enhanced the antitumor activity of ionizing radiation (IR), leading to tumor growth inhibition in vivo. These results demonstrate that ZIP4 is a novel prognostic factor for malignant NPC progression. More importantly, targeting ZIP4, along with radiotherapy, may be an effective new treatment for NPC.
Inhibition of transmembrane TNF-α shedding by a specific antibody protects against septic shock
Authors: Li Chenxi , Gu Haiyan , Yu Mingxia , Yang Peng , Zhang Meng , Ba Hongping , Yin Yue , Wang Jing , Yin Bingjiao , Zhou Xiaoxi , Li Zhuoya 
Published: August 2019

AbstractTransmembrane TNF-α (tmTNF-α) and secretory TNF-α (sTNF-α) display opposite effects in septic shock. Reducing tmTNF-α shedding can offset the detrimental effects of sTNF-α and increase the beneficial effect of tmTNF-α. We previously developed a monoclonal antibody that is specific for tmTNF-α and does not cross-react with sTNF-α. In this study, we show that this antibody can specifically suppress tmTNF-α shedding by competing with a TNF-α converting enzyme that cleaves the tmTNF-α ectodomain to release sTNF-α. This tmTNF-α antibody significantly inhibited LPS-induced secretion of interleukin (IL)-1β, IL-6, interferon-β, and nitric oxide by monocytes/macrophages, and protected mice from septic shock induced by lipopolysaccharide (LPS) or cecal ligation and puncture, while reducing the bacterial load. The mechanism associated with the protective effect of this tmTNF-α antibody involved promotion of LPS-induced toll-like receptor 4 (TLR4) internalization and degradation by recruiting Triad3A to TLR4. Moreover, the tmTNF-α antibody inhibited LPS-induced activation of nuclear factor-κB and interferon regulatory factor 3 pathways by upregulating expression of A20 and monocyte chemotactic protein-induced protein 1. Similarly, treatment of macrophages with exogenous tmTNF-α suppressed LPS/TLR4 signaling and release of proinflammatory cytokines, indicating that increased levels of tmTNF-α promoted by the antibody contributed to its inhibitory effect. Thus, use of this tmTNF-α antibody for specific suppression of tmTNF-α shedding may be a promising strategy to treat septic shock.
Long noncoding RNA DANCR regulates proliferation and migration by epigenetically silencing FBP1 in tumorigenesis of cholangiocarcinoma
Authors: Wang Ni , Zhang Chongguo , Wang Wulin , Liu Jie , Yu Yang , Li You , Zhang Mingjiong , Ge Xianxiu , Li Quanpeng , Miao Lin 
Published: August 2019

AbstractRecently, long noncoding RNAs (lncRNAs) have been shown to play significant regulatory roles in human tumorigenesis. However, the biological function of lncRNAs in cholangiocarcinoma (CCA) remains largely unknown. In this study, DANCR was shown to be significantly upregulated in CCA. DANCR regulated the proliferation and migration of CCA cells in vitro. Moreover, downregulation of DANCR suppressed CCA cells proliferation in vivo. RNA-seq revealed that DANCR knockdown preferentially affected genes linked with cell proliferation and cell differentiation. Furthermore, mechanistic investigation validated that DANCR could bind EZH2 and modulate the histone methylation of promoter of FBP1, thereby regulating CCA cells growth and migration. Taken together, these results demonstrated the significant roles of DANCR in CCA and may provide a theoretical basis for clinical diagnosis and treatment of CCA.