bluuebunny/crossref_metadata_2025 huggingface dataset:
Uniqueness for measure-valued equations of nonlinear filtering for stochastic dynamical systems with Lévy noise
Authors: Qiao Huijie
Published: July 2018

In the paper we study the Zakai and Kushner–Stratonovich equations of the nonlinear filtering problem for a non-Gaussian signal-observation system. Moreover, we prove that under some general assumption, the Zakai equation has pathwise uniqueness and uniqueness in joint law, and the Kushner–Stratonovich equation is unique in joint law.
On Seneta–Heyde scaling for a stable branching random walk
Authors: He Hui , Liu Jingning , Zhang Mei
Published: July 2018

We consider a discrete-time branching random walk in the boundary case, where the associated random walk is in the domain of attraction of an α-stable law with 1 < α < 2. We prove that the derivative martingale Dn converges to a nontrivial limit D∞ under some regular conditions. We also study the additive martingale Wn and prove that n1/αWn converges in probability to a constant multiple of D∞.
Local asymptotics for the area under the random walk excursion
Authors: Perfilev Elena , Wachtel Vitali
Published: July 2018

We study the tail behaviour of the distribution of the area under the positive excursion of a random walk which has negative drift and light-tailed increments. We determine the asymptotics for local probabilities for the area and prove a local central limit theorem for the duration of the excursion conditioned on the large values of its area.
Forward-reverse expectation-maximization algorithm for Markov chains: convergence and numerical analysis
Authors: Bayer Christian , Mai Hilmar , Schoenmakers John
Published: July 2018

We develop a forward-reverse expectation-maximization (FREM) algorithm for estimating parameters of a discrete-time Markov chain evolving through a certain measurable state-space. For the construction of the FREM method, we develop forward-reverse representations for Markov chains conditioned on a certain terminal state. We prove almost sure convergence of our algorithm for a Markov chain model with curved exponential family structure. On the numerical side, we carry out a complexity analysis of the forward-reverse algorithm by deriving its expected cost. Two application examples are discussed.
On the significands of uniform random variables
Authors: Berger Arno , Twelves Isaac
Published: July 2018

For all α > 0 and real random variables X, we establish sharp bounds for the smallest and the largest deviation of αX from the logarithmic distribution also known as Benford's law. In the case of uniform X, the value of the smallest possible deviation is determined explicitly. Our elementary calculation puts into perspective the recurring claims that a random variable conforms to Benford's law, at least approximately, whenever it has large spread.
Joint distribution of a Lévy process and its running supremum
Authors: Coutin Laure , Pontier Monique , Ngom Waly
Published: July 2018

Let X be a jump-diffusion process and X* its running supremum. In this paper we first show that for any t > 0, the law of the pair (X*t, Xt) has a density with respect to the Lebesgue measure. This allows us to show that for any t > 0, the law of the pair formed by the random variable Xt and the running supremum X*t of X at time t can be characterized as a weak solution of a partial differential equation concerning the distribution of the pair (X*t, Xt). Then we obtain an expression of the marginal density of X*t for all t > 0.
First-passage time asymptotics over moving boundaries for random walk bridges
Authors: Sloothaak Fiona , Wachtel Vitali , Zwart Bert
Published: July 2018

We study the asymptotic tail behavior of the first-passage time over a moving boundary for a random walk conditioned to return to zero, where the increments of the random walk have finite variance. Typically, the asymptotic tail behavior may be described through a regularly varying function with exponent -½, where the impact of the boundary is captured by the slowly varying function. Yet, the moving boundary may have a stronger effect when the tail is considered at a time close to the return point of the random walk bridge, leading to a possible phase transition depending on the order of the distance between zero and the moving boundary.
Epigenetics and bone diseases
Authors: Huang Tu , Peng Xiu , Li Zhenxia , Zhou Quan , Huang Shishu , Wang Yuting , Li Juan , Song Youqiang
Published: July 2018

Owing to the development of new technologies, the epigenome, a second dimensional method for genome analysis has emerged. Epigenetic mechanisms, including DNA methylation, histone modifications and noncoding RNAs, regulate gene expression without changing the genetic sequence. These epigenetic mechanisms normally modulate gene expression, trans-generational effects and inherited expression states in various biological processes. Abnormal epigenetic patterns typically cause pathological conditions, including cancers, age-related diseases, and specific cartilage and bone diseases. Facing the rapidly developing epigenetic field, we reviewed epigenetic mechanisms and their involvement with the skeletal system and their role in skeletal development, homeostasis and degeneration. Finally, we discuss the prospects for the future of epigenetics.
Classification of sugarcane varieties using visible/near infrared spectral reflectance of stalks and multivariate methods
Authors: Steidle Neto A. J. , Lopes D. C. , Toledo J. V. , Zolnier S. , Silva T. G. F.
Published: July 2018

The use of fast and non-destructive techniques for identifying sugarcane varieties enables the development of automatic sorting systems, contributing towards improving pre-processing steps in the alcohol and sugar industries. In this context, principal component analysis (PCA), factorial discriminant analysis (FDA), stepwise forward discriminant analysis (SFDA) and partial least-squares discriminant analysis (PLS-DA) were used to classify four Brazilian sugarcane varieties based on visible/near infrared (Vis/NIR) spectral reflectance measurements (450–1000 nm range) of stalks. All wavelengths contributed towards discriminating the sugarcane varieties, but the 600–750 nm range was most relevant. When evaluating PCA results considering the four sugarcane varieties, two of them overlapped and it was only possible to use classifiers of three varieties. Factorial discriminant analysis, PLS-DA and SFDA reached correct classifications of 0.81, 0.82 and 0.74, respectively, when considering the external validation data and the four sugarcane varieties evaluated. Results showed that Vis/NIR spectroscopy combined with discriminating methods is a promising tool for non-destructive and fast sugarcane variety classification, which can be used in the agro-food industry or directly in the field.
Experimental evidence for shaping and bloom inducing effects of decapod larvae of Xantho poressa (Olivi, 1792) on marine phytoplankton
Authors: Tanković Mirta Smodlaka , Baričević Ana , Perusco Victor Stinga , Melzer Roland R. , Lopez Alejandro Izquierdo , Dömel Jana Sophie , Heß Martin , Kužat Nataša , Pfannkuchen Daniela Marić , Pfannkuchen Martin
Published: July 2018

To study zooplankton–phytoplankton relationships in the diatom-dominated plankton communities of the northern Adriatic we performed feeding experiments with diatoms and zoea I larvae of the brachyuran Xantho poressa. We found that zoea I of X. poressa feed on diatoms of different forms (centric, pennate, colony forming, single celled, with or without setae) and size classes. In a laboratory setup, we presented the zoeas with a mix of diatom species similar to communities observed during blooms regularly found in the northern Adriatic. We report that the grazing activity resulted in a decrease of the relative abundance of the toxic diatom Pseudo-nitzschia calliantha. For the colonial, bloom-forming diatom Skeletonema marinoi our results show a chain length reduction in the presence of zoea I. Of particular interest is the observation that the presence of larvae also resulted in an increased growth rate and abundance of S. marinoi, which resembles bloom induction by grazer presence.
Exploring shared genetic bases and causal relationships of schizophrenia and bipolar disorder with 28 cardiovascular and metabolic traits
Authors: So Hon-Cheong , Chau Kwan-Long , Ao Fu-Kiu , Mo Cheuk-Hei , Sham Pak-Chung
Published: July 2018

Background

Cardiovascular diseases represent a major health issue in patients with schizophrenia (SCZ) and bipolar disorder (BD), but the exact nature of cardiometabolic (CM) abnormalities involved and the underlying mechanisms remain unclear. Psychiatric medications are known risk factors, but it is unclear whether there is a connection between the disorders (SCZ/BD) themselves and CM abnormalities.

Methods

Using polygenic risk scores and linkage disequilibrium score regression, we investigated the shared genetic bases of SCZ and BD with 28 CM traits. We performed Mendelian randomization (MR) to elucidate causal relationships between the two groups of disorders. The analysis was based on large-scale meta-analyses of genome-wide association studies. We also identified the potential shared genetic variants and inferred the pathways involved.

Results

We found tentative polygenic associations of SCZ with glucose metabolism abnormalities, adverse adipokine profiles, increased waist-to-hip ratio and visceral adiposity (false discovery rate or FDR<0.05). However, there was an inverse association with body mass index. For BD, we observed several polygenic associations with favorable CM profiles at FDR<0.05. MR analysis showed that SCZ may be causally linked to raised triglyceride and that lower fasting glucose may be linked to BD. We also identified numerous single nucleotide polymorphisms and pathways shared between SCZ/BD with CM traits, some of which are related to inflammation or the immune system.

Conclusions

Our findings suggest that SCZ patients may be genetically predisposed to several CM abnormalities independent of medication side effects. On the other hand, CM abnormalities in BD may be more likely to be secondary. However, the findings require further validation.
The long-term effect of typhoons on vascular epiphytes in Taiwan
Authors: Hsu Rebecca C.-C. , Wolf Jan H.D. , Tsai Jer-Min , Lin Yi-Chin
Published: July 2018

We used all 167 typhoon warnings issued by the Taiwanese Central Weather Bureau from 1958–2006 to assess the long-term effect of cyclone disturbance on vascular epiphytes. Tracks and eyes of past typhoons were plotted as circles with radii of Beaufort scale 7 and 10, and the frequency of each cohort in 1-km2 grid cells was calculated. The presence of vascular epiphytes in the same grid cells was predicted using species distribution models (SDMs). First, we used herbarium specimens and other sources to compile a comprehensive georeferenced vascular epiphyte database that contained 39084 records in 331 species. Next, we assigned each epiphyte record to a cell in the same 1-km2 grid as above. Finally, we used SDMs (MaXent), based on 30 environmental variables except typhoon frequency, to predict the potential presence of each species in the grid cells. For our analysis we only considered cells east of the central mountain ridge where typhoons hit with full force. After elimination of rare species and species that could not be validated in the SDMs, we were left with 156 epiphyte species in 10725 1-km2 cells. The number of projected species in the cells was 36.5 on average, varying between two and 82 species. Correlation analyses showed that, over time, typhoons led to a decrease in epiphyte richness at Beaufort scale 7 and 10 (Pearson's r = −0.07 and −0.08 respectively). Ferns, orchids, hemiepiphytes and dicotyledons generally showed the same pattern, except hemiepiphytes that showed a positive correlation at B7 (Pearson's r = 0.15). A partial canonical correspondence ordination analysis showed that, independent of temperature- and rainfall-related variables, Beaufort scale 7 and 10 typhoons also had significant influence on the species composition of the vascular epiphyte communities in the landscape. We recommend in situ monitoring of epiphytes over a long period to corroborate the suggestion from this indirect study that typhoons have a long-term effect on the distribution of epiphytes in Taiwan.
Unambiguous Tracking Technique Based on Combined Correlation Functions for Sine BOC Signals
Authors: Li Tian , Tang Zuping , Wei Jiaolong , Zhou Zhihui , Wang Boyi
Published: July 2018

A new unambiguous tracking technique based on combined correlation functions for sine Binary Offset Carrier (BOC) signals is proposed in this paper. The key to this method is to exploit two types of local reference signals: the BOC signal and a linear combination of a series of BOC signals with different delays. They are both correlated with the received signals. Then, a correlation function without any positive side peaks is obtained by multiplying the two correlation results to make tracking completely unambiguous. Theoretical analysis and simulation in the tracking stage show that the proposed method has the best code tracking accuracy among the method tracking BOC signals like Binary Phase-Shift Keying signals (BPSK-LIKE), the Pseudo correlation function based Unambiguous Delay Lock Loop (PUDLL), Symmetrical Pulse Ambiguity Removing (SPAR) technique, the method proposed by Shen Feng (SF) and the two methods proposed by Yan Tao (YT-V1 and YT-V2). In multipath environments, the proposed method has the best anti-multipath performance of all the tracking methods mentioned above. In conclusion, the proposed method can completely eliminate ambiguity and has significant performance advantages compared with the methods mentioned above.
Multicriteria Analysis Method for Evaluation of Vessel Simulation Models in Open Waters
Authors: Czaplewski Krzysztof , Zwolan Piotr
Published: July 2018

Modern ship simulators enable simulations of reality using available environment and ship models. When choosing a specific vessel from a catalogue, however, it is not always immediately apparent as to how true a simulation is to the original vessel. Its makers are required only to have software certificates, which does not ensure the exact modelling of a ship in the simulation. This paper presents research in continuation of previous work presenting a general methodology for the evaluation of the degree of accuracy of a simulated ship model compared to its real-world counterpart. In this paper, the results are shown of a comparative analysis based on actual measurements with the use of one of the methods of multi-criteria analysis. Furthermore, the methodology for the construction of ship models is presented. The paper concludes with a test verifying the accuracy of the assumptions.
Skorupski and Broome on the Agent-Neutral/Relative Distinction
Authors: BUCKLAND JAMIE
Published: July 2018

I have two aims in this article. The first is to break the deadlocked exchange between John Skorupski and John Broome concerning how best to understand Thomas Nagel's distinction between agent-neutral and agent-relative reasons for action. The second is to provide a reformulation of the distinction which captures an uncontroversial distinction between those reason-giving considerations which encapsulate an indexical relationship between an agent and an object of moral concern, and those which do not. The resolution of this exchange, and subsequent reformulation of the dichotomy, has two important ramifications for contemporary debates in moral philosophy. First and foremost, it reveals the true, pre-theoretical nature of the distinction between agent-neutral and agent-relative reasons for action, and how the notion of agent-relativity cannot be utilized to underwrite the existence of deontic constraints. And, second, it provides definitive support for Skorupski's claim that agent-relative reasons are not the defining feature of deontological ethics.
The transforming city in nineteenth-century literary journalism: Ramón de Mesonero Romanos’ ‘Madrid scenes’ and Charles Dickens’ ‘Street sketches’
Authors: SCHWAB CHRISTIANE
Published: July 2018

Nineteenth-century urbanization and industrialization in western Europe have clearly contributed to the formation of societal knowledge and self-reflexive cultural iconographies. Especially from the 1820s onwards, one major context for discussing the social and cultural diversity of the city and concomitant socio-political tensions was the emerging market of journals and magazines. Based upon the writings of two exemplary authors, this article investigates with which techniques and metaphors nineteenth-century journalistic sketches depicted urban sociability and conditions. Furthermore, it reflects on how not only the ever more differentiating urban environments but also the proximity of different networks and institutions of knowledge encouraged the refinement of social observation and thought. Exploring a neglected genre of social knowledge production, the article proposes new perspectives for urban history and aims at stimulating a critical review of contemporary research practices in all branches of the social sciences.
Mechanism of Etching of Al-4.5Mg-1.0Mn Alloy
Authors: Gabbardo Aline D. , Wang Xi , Huggins Angeire , Frankel G. S.
Published: July 2018

5xxx series aluminum alloys, as Al-4.5Mg-1.0Mn (AA5083), are strengthened by Mg solid solution and work hardening. A drawback of this alloy is the fact thatβphase, Al3Mg2, can precipitate on grain boundaries causing sensitization and intergranular corrosion, which is detrimental to the integrity of the structure. Metallography is an important technique to study the grain structure and highly sought for intergranular corrosion evaluation; however, revealing the grains of completely un-sensitized AA5083 is challenging. This paper introduces a new procedure to etch AA5083 samples that were solutionized at 450°C for 1.5 h. The new procedure is a two-step etching method, including a phosphoric acid pre-etching step and a Weck’s reagent coloring step. Solutionized, lightly sensitized, and as-received AA5083 were evaluated, and the grains were observed using optical microscopy. The microetching mechanism was further studied by optical profilometry, atomic force microscopy, scanning electron microscopy, and energy dispersive spectrometry. The phosphoric acid created a surface profile determined by the grain orientations and its reactivity, and the Weck’s reagent was then able to color grains by preferential MnO2formation over some pre-etched grains. Moreover, the final polishing with colloidal silica was essential to reach a high contrast image.
Effects of Confinement on Reaction‐Induced Fracturing During Hydration of Periclase
Authors: Zheng Xiaojiao , Cordonnier Benoît , Zhu Wenlu , Renard François , Jamtveit Bjørn
Published: July 2018

Hydration of a nominally dry rock can cause expansion of the solid volume, resulting in reaction‐induced fracturing and an associated increase in the porosity and permeability of the rock. We study the effect of confinement on the coupling between stress generation, reaction‐induced fracturing, and porosity evolution during the hydration of periclase (MgO) into brucite (Mg(OH)2). Samples of a microporous MgO ceramic were hydrated at 170–210 °C, 5–80 MPa confining pressure, 6–95 MPa differential stress, and 5–75 MPa pore fluid pressure in a purpose‐designed triaxial load cell. Hydration‐induced changes were recorded in situ by X‐ray microtomographic imaging at 5‐min intervals. Below 30 MPa effective mean stress, the fraction of periclase replaced by brucite is a sigmoidal function of time. After a slow start, the replacement rate picks up with concomitant intense fracturing. The porosity increase resulting from the reaction‐induced fractures is transient (pulse‐like). Following the porosity pulse the rate of replacement declines until the replacement is almost complete. Above 30 MPa, the reaction rate is slow, porosity decreases monotonically without any observable fracturing during the time of the experiment. At these stress conditions, the lack of fracturing cannot be limited by the thermodynamic affinity of the reaction. A possible interpretation is that the stress generated by the reaction may overcome the disjoining pressure at the grain‐grain interface, expelling the water film trapped there and thereby dramatically reducing the reaction rate.
Southwest Pacific Absolute Plate Kinematic Reconstruction Reveals Major Cenozoic Tonga‐Kermadec Slab Dragging
Authors: van de Lagemaat Suzanna H. A. , van Hinsbergen Douwe J. J. , Boschman Lydian M. , Kamp Peter J. J. , Spakman Wim
Published: July 2018

Tectonic plates subducting at trenches having strikes oblique to the absolute subducting plate motion undergo trench‐parallel slab motion through the mantle, recently defined as a form of “slab dragging.” We investigate here long‐term slab‐dragging components of the Tonga‐Kermadec subduction system driven by absolute Pacific plate motion. To this end we develop a kinematic restoration of Tonga‐Kermadec Trench motion placed in a mantle reference frame and compare it to tomographically imaged slabs in the mantle. Estimating Tonga‐Kermadec subduction initiation is challenging because another (New Caledonia) subduction zone existed during the Paleogene between the Australia and Pacific plates. We test partitioning of plate convergence across the Paleogene New Caledonia and Tonga‐Kermadec subduction zones against resulting mantle structure and show that most, if not all, Tonga‐Kermadec subduction occurred after ca. 30 Ma. Since then, Tonga‐Kermadec subduction has accommodated 1,700 to 3,500 km of subduction along the southern and northern ends of the trench, respectively. When placed in a mantle reference frame, the predominantly westward directed subduction evolved while the Tonga‐Kermadec Trench underwent ~1,200 km of northward absolute motion. We infer that the entire Tonga‐Kermadec slab was laterally transported through the mantle over 1,200 km. Such slab dragging by the Pacific plate may explain observed deep‐slab deformation and may also have significant effects on surface tectonics, both resulting from the resistance to slab dragging by the viscous mantle.
Influence of Bed‐Load Transport on Flow Resistance of Step‐Pool Channels
Authors: Hohermuth B. , Weitbrecht V.
Published: July 2018

This study investigates the influence of bed‐load transport on flow resistance and bed stability in steep step‐pool channels. A total of 86 flume experiments was performed. Stable step‐pool sequences were formed with increasing discharge under clear‐water conditions. The addition of fine bed‐load material to the flow led to a decrease in bed roughness and an increased mobility of step‐forming clasts. Velocity measurements showed that bed‐load transport significantly decreased flow resistance and increased near‐bed velocity for the conditions investigated. A set of existing resistance equations was tested against our data, of which the hydraulic geometry relation performed best. However, none of the existing equations was able to reproduce flow resistance during active bed‐load transport. Two new resistance equations based on a hydraulic geometry approach are proposed for conditions with and without bed‐load transport. The increase in near‐bed velocity associated with bed‐load transport was identified as the main cause for the observed increase in step mobility associated with bed‐load transport. For flows with bed‐load transport, step‐forming clasts were mobilized at discharges some 10% to 30% lower than under clear‐water conditions.
Exploring the Paradox of Increased Global Health and Degraded Global Environment: How Much Borrowed Time Is Humanity Living on?
Authors: Filippelli Gabriel M.
Published: July 2018

Ample documentation of the global environmental degradation of air, land, and water paints a grim picture for the future of humanity. And yet by all measures global human health and well‐being have been improving significantly over the past several decades, including significant improvements in middle‐ and low‐income countries as well. The causes and consequences of this apparent paradox have not received the attention that they deserve, largely because they are measured and studied by different fields of inquiry. A systems approach that focuses on the drivers behind this apparent paradox of environmental degradation and human health improvement must include a combination of social and technological developments that have improved resource use, distribution, and innovation. But in many cases, such as phosphate resources and flying insect populations, the resource bank is not inexhaustible or replaceable, and priority must be placed for research and action on those critical resources upon which planetary health relies. Particularly, providing greater support and access to the table for youth leaders may be one way to create space for this first true generation of Anthroponauts to lead with solutions to our resource problems and to help build balance back into the environment‐health equation.
Lunar Swirl Morphology Constrains the Geometry, Magnetization, and Origins of Lunar Magnetic Anomalies
Authors: Hemingway Douglas J. , Tikoo Sonia M.
Published: July 2018

Lunar swirls are collections of finely structured bright and dark surface markings, alternating over length scales of typically 1–5 km. If swirls are the result of plasma interactions with crustal magnetic anomalies or electrostatic or magnetic sorting of fine materials, the magnetic field orientation must vary over similar length scales. This requires that the associated source bodies be both shallow and narrow in horizontal extent. The correspondingly restricted volume of the source bodies in turn implies strong rock magnetization. Here we show that if ∼300‐nT surface fields are necessary to produce observable swirl markings, the required rock magnetization must be >0.5 A/m, even for very shallow sources and likely closer to ∼2 A/m or more. This strong source rock magnetization, together with the geometric constraints that favor magmatic structures such as dikes or lava tubes, requires a mechanism to enhance the magnetic carrying capacity of the rocks. We propose that heating associated with magmatic activity could thermochemically alter host rocks and impart them with magnetizations an order of magnitude stronger than is typical of lunar mare basalts. Our results both place constraints on the geometry and magnetization of the source bodies and provide clues about the possible origins of the Moon's crustal magnetic anomalies.
Predictable Oxygen Isotope Exchange Between Plant Lipids and Environmental Water: Implications for Ecosystem Water Balance Reconstruction
Authors: Maxwell Toby M. , Silva Lucas C. R. , Horwath William R.
Published: July 2018

In this study, we present the first evidence for predictable exchange of oxygen isotopes between water and lipid compounds. Using laboratory incubations with aliphatic alcohols, hexadecanol and eicosanol, and bulk soil lipid extracts in isotopically enriched water for 160 days, we determined the magnitude and direction of exchange rates for bulk and compound‐specific lipid extracts. Our data show that δ18O ratios of long‐chain aliphatic lipids that persist in hydrophobic portions of soil organic matter integrate the signature of plant water δ18O values, which can be used to reconstruct hydrologic shifts in terrestrial systems. For bulk lipid extracts, equilibrium was reached, indicating that 22% of its oxygen content is exchangeable with a half‐life of 0.13 years. Incubations with the same bulk lipid extracts in contact with iron oxyhydroxide minerals showed no difference in exchange rates, although the exchangeable fraction decreases to 19% of the total. This result suggests that mineral surfaces can inhibit oxygen exchange for some oxygen‐containing functional groups. In contrast, pure compounds showed stable oxygen isotope signatures with no exchange under the same conditions. Taken together, these findings represent a significant development in the mechanistic understanding and application of oxygen isotopes in plant‐ and soil‐derived lipids, toward a path for the use of lipid extracts in reconstructions of ecosystem water balance.
Global Land Surface Modeling Including Lateral Groundwater Flow
Authors: Zeng Yujin , Xie Zhenghui , Liu Shuang , Xie Jinbo , Jia Binghao , Qin Peihua , Gao Junqiang
Published: July 2018

The groundwater system is an essential part of Earth's systems. However, most current land surface models (LSMs) for climate modeling do not explicitly account for the lateral groundwater flow process. In this study, schemes describing LSM‐lateral groundwater flow module coupling, model resolution conversion, and parallel simulation were designed and implemented to incorporate a lateral groundwater flow module into the Community Land Model 4.5. The depth to less permeable bedrock also was included in the large‐scale groundwater flow modeling. Model validation was performed using multiple observations from the 20‐year continuous groundwater table depth measurements at 67 stations in 10 countries, 1.6 million worldwide time‐averaged groundwater table depth measurements, previous knowledge about the locations of major aquifer systems, and inversed terrestrial water storage anomalies derived from satellite data. The simulated results show that the groundwater table pattern is a combined reflection of climatic and topographic factors across a range of spatial scales. Lateral groundwater flow significantly modified the equilibrium water table patterns in North Africa, the Arabian Peninsula, central Asia, and southern Australia, deepening the water tables by more than 6 m. The trend of deepening groundwater tables observed between 1970 and 2010, which was found to be 0.025 to 0.125 m/decade, was exacerbated by the lateral flow; however, the seasonal variability of the groundwater table depth was reduced by the buffering effect of the lateral flow.
Pilot Study to Examine the Clinical Utility of Biofeedback in Solid Organ Transplant
Authors: McKenna Kristine , Goodrich Lara , Forbes Peter W. , Ibeziako Patricia
Published: July 2018

Biofeedback-assisted relaxation training (BART) is a useful therapeutic tool for treating pain and anxiety, 2 common issues for patients waiting for and recovering from transplant. Most applications occur in outpatient settings and current research exploring this intervention with transplant patients is limited. The impact of BART on patient-reported mood and pain during hospitalizations is explored. Forty patients referred to transplant psychology for assistance in managing pain and/or anxiety during medical admissions participated in BART. Patients ranged in age from 9 to 23 years ( M = 15.5, SD = 3.7) and completed an average of 2.1 sessions per admission (range: 1–6). BART was utilized by 20 patients prior to transplant, 24 patients posttransplant, and 4 patients both before and after transplant. Mood improvements were reported after BART, regardless of pain level (pre: M = 6.05, SD = 2.28, post: M = 7.45, SD = 1.92, p < .0001). Patients with self-reported pain at the start of the BART session endorsed lower pain at the end ( M = 5.1, SD = 2.1; M = 3.4, SD = 2.4, respectively; p < .001). Average heart coherence differed between organ groups (range of group means: 22.9–42.3, p = .003), with heart and lung transplant patients having lower levels than liver and renal transplant patients. BART may be particularly helpful for pain and anxiety management during admissions prior to solid organ transplant. Preliminary data suggest that BART may be differentially effective for solid organ groups. Practical considerations regarding the implementation of a technology-based psychological intervention across transplant populations also are discussed.

Implications for Impact Statement

This study suggests that biofeedback-assisted relaxation training may be a helpful intervention for management of anxiety and pain symptoms of solid organ transplant patients. It can be used as a brief treatment (2 sessions on average) during hospitalizations before or after transplant surgery.
Oxidation of KCNB1 channels in the human brain and in mouse model of Alzheimer’s disease
Authors: Wei Yu , Shin Mi Ryung , Sesti Federico
Published: July 2018

Oxidative modification of the voltage-gated K+channel subfamily B member 1 (KCNB1, Kv2.1) is emerging as a mechanism of neuronal vulnerability potentially capable of affecting multiple conditions associated with oxidative stress, from normal aging to neurodegenerative disease. In this study we report that oxidation of KCNB1 channels is exacerbated in the post mortem brains of Alzheimer’s disease (AD) donors compared to age-matched controls. In addition, phosphorylation of Focal Adhesion kinases (FAK) and Src tyrosine kinases, two key signaling steps that follow KCNB1 oxidation, is also strengthened in AD vs. control brains. Quadruple transgenic mice expressing a non-oxidizable form of KCNB1 in the 3xTg-AD background (APPSWE, PS1M146V, and tauP301L), exhibit improved working memory along with reduced brain inflammation, protein carbonylation and intraneuronal β-amyloid (Aβ) compared to 3xTg-AD mice or mice expressing the wild type (WT) KCNB1 channel. We conclude that oxidation of KCNB1 channels is a mechanism of neuronal vulnerability that is pervasive in the vertebrate brain.
Distinct multiple fermionic states in a single topological metal
Authors: Hosen M. Mofazzel , Dimitri Klauss , Nandy Ashis K. , Aperis Alex , Sankar Raman , Dhakal Gyanendra , Maldonado Pablo , Kabir Firoza , Sims Christopher , Chou Fangcheng , Kaczorowski Dariusz , Durakiewicz Tomasz , Oppeneer Peter M. , Neupane Madhab
Published: July 2018

Among the quantum materials that have recently gained interest are the topological insulators, wherein symmetry-protected surface states cross in reciprocal space, and the Dirac nodal-line semimetals, where bulk bands touch along a line in k-space. However, the existence of multiple fermion phases in a single material has not been verified yet. Using angle-resolved photoemission spectroscopy (ARPES) and first-principles electronic structure calculations, we systematically study the metallic material Hf2Te2P and discover properties, which are unique in a single topological quantum material. We experimentally observe weak topological insulator surface states and our calculations suggest additional strong topological insulator surface states. Our first-principles calculations reveal a one-dimensional Dirac crossing—the surface Dirac-node arc—along a high-symmetry direction which is confirmed by our ARPES measurements. This novel state originates from the surface bands of a weak topological insulator and is therefore distinct from the well-known Fermi arcs in semimetals.
SUMO-mediated regulation of NLRP3 modulates inflammasome activity
Authors: Barry Rachael , John Sidonie Wicky , Liccardi Gianmaria , Tenev Tencho , Jaco Isabel , Chen Chih-Hong , Choi Justin , Kasperkiewicz Paulina , Fernandes-Alnemri Teresa , Alnemri Emad , Drag Marcin , Chen Yuan , Meier Pascal
Published: July 2018

The NLRP3 inflammasome responds to infection and tissue damage, and rapidly escalates the intensity of inflammation by activating interleukin (IL)-1β, IL-18 and cell death by pyroptosis. How the NLRP3 inflammasome is negatively regulated is poorly understood. Here we show that NLRP3 inflammasome activation is suppressed by sumoylation. NLRP3 is sumoylated by the SUMO E3-ligase MAPL, and stimulation-dependent NLRP3 desumoylation by the SUMO-specific proteases SENP6 and SENP7 promotes NLRP3 activation. Defective NLRP3 sumoylation, either by NLRP3 mutation of SUMO acceptor lysines or depletion of MAPL, results in enhanced caspase-1 activation and IL-1β release. Conversely, depletion of SENP7 suppresses NLRP3-dependent ASC oligomerisation, caspase-1 activation and IL-1β release. These data indicate that sumoylation of NLRP3 restrains inflammasome activation, and identify SUMO proteases as potential drug targets for the treatment of inflammatory diseases.
99TcO4− remediation by a cationic polymeric network
Authors: Li Jie , Dai Xing , Zhu Lin , Xu Chao , Zhang Duo , Silver Mark A. , Li Peng , Chen Lanhua , Li Yongzhong , Zuo Douwen , Zhang Hui , Xiao Chengliang , Chen Jing , Diwu Juan , Farha Omar K. , Albrecht-Schmitt Thomas E. , Chai Zhifang , Wang Shuao
Published: July 2018

Direct removal of 99TcO4− from the highly acidic solution of used nuclear fuel is highly beneficial for the recovery of uranium and plutonium and more importantly aids in the elimination of 99Tc discharge into the environment. However, this task represents a huge challenge given the combined extreme conditions of super acidity, high ionic strength, and strong radiation field. Here we overcome this challenge using a cationic polymeric network with significant TcO4− uptake capabilities in four aspects: the fastest sorption kinetics, the highest sorption capacity, the most promising uptake performance from highly acidic solutions, and excellent radiation-resistance and hydrolytic stability among all anion sorbent materials reported. In addition, this material is fully recyclable for multiple sorption/desorption trials, making it extremely attractive for waste partitioning and emergency remediation. The excellent TcO4− uptake capability is elucidated by X-ray absorption spectroscopy, solid-state NMR measurement, and density functional theory analysis on anion coordination and bonding.
Optimal control theory enables homonuclear decoupling without Bloch–Siegert shifts in NMR spectroscopy
Authors: Coote Paul W. , Robson Scott A. , Dubey Abhinav , Boeszoermenyi Andras , Zhao Mengxia , Wagner Gerhard , Arthanari Haribabu
Published: July 2018

The Bloch–Siegert shift is a phenomenon in NMR spectroscopy and atomic physics in which the observed resonance frequency is changed by the presence of an off-resonance applied field. In NMR, it occurs especially in the context of homonuclear decoupling. Here we develop a practical method for homonuclear decoupling that avoids inducing Bloch–Siegert shifts. This approach enables accurate observation of the resonance frequencies of decoupled nuclear spins. We apply this method to increase the resolution of the HNCA experiment. We also observe a doubling in sensitivity for a 30 kDa protein. We demonstrate the use of band-selective Cβ decoupling to produce amino acid-specific line shapes, which are valuable for assigning resonances to the protein sequence. Finally, we assign the backbone of a 30 kDa protein, Human Carbonic Anhydrase II, using only HNCA experiments acquired with band-selective decoupling schemes, and instrument time of one week.
A mapping framework of competition–cooperation QTLs that drive community dynamics
Authors: Jiang Libo , He Xiaoqing , Jin Yi , Ye Meixia , Sang Mengmeng , Chen Nan , Zhu Jing , Zhang Zuoran , Li Jinting , Wu Rongling
Published: July 2018

Genes have been thought to affect community ecology and evolution, but their identification at the whole-genome level is challenging. Here, we develop a conceptual framework for the genome-wide mapping of quantitative trait loci (QTLs) that govern interspecific competition and cooperation. This framework integrates the community ecology theory into systems mapping, a statistical model for mapping complex traits as a dynamic system. It can characterize not only how QTLs of one species affect its own phenotype directly, but also how QTLs from this species affect the phenotype of its interacting species indirectly and how QTLs from different species interact epistatically to shape community behavior. We validated the utility of the new mapping framework experimentally by culturing and comparing two bacterial species, Escherichia coli and Staphylococcus aureus, in socialized and socially isolated environments, identifying several QTLs from each species that may act as key drivers of microbial community structure and function.
Clade diversification dynamics and the biotic and abiotic controls of speciation and extinction rates
Authors: Aguilée Robin , Gascuel Fanny , Lambert Amaury , Ferriere Regis
Published: July 2018

How ecological interactions, genetic processes, and environmental variability jointly shape the evolution of species diversity remains a challenging problem in biology. We developed an individual-based model of clade diversification to predict macroevolutionary dynamics when resource competition, genetic differentiation, and landscape fluctuations interact. Diversification begins with a phase of geographic adaptive radiation. Extinction rates rise sharply at the onset of the next phase. In this phase of niche self-structuring, speciation and extinction processes, albeit driven by biotic mechanisms (competition and hybridization), have essentially constant rates, determined primarily by the abiotic pace of landscape dynamics. The final phase of diversification begins when intense competition prevents dispersing individuals from establishing new populations. Species’ ranges shrink, causing negative diversity-dependence of speciation rates. These results show how ecological and microevolutionary processes shape macroevolutionary dynamics and rates; they caution against the notion of ecological limits to diversity, and suggest new directions for the phylogenetic analysis of diversification.
Targeted delivery of CRISPR-Cas9 ribonucleoprotein into arthropod ovaries for heritable germline gene editing
Authors: Chaverra-Rodriguez Duverney , Macias Vanessa M. , Hughes Grant L. , Pujhari Sujit , Suzuki Yasutsugu , Peterson David R. , Kim Donghun , McKeand Sage , Rasgon Jason L.
Published: July 2018

Cas9-mediated gene editing is a powerful tool for addressing research questions in arthropods. Current approaches rely upon delivering Cas9 ribonucleoprotein (RNP) complex by embryonic microinjection, which is challenging, is limited to a small number of species, and is inefficient even in optimized taxa. Here we develop a technology termed Receptor-Mediated Ovary Transduction of Cargo (ReMOT Control) to deliver Cas9 RNP to the arthropod germline by injection into adult female mosquitoes. We identify a peptide (P2C) that mediates transduction of Cas9 RNP from the female hemolymph to the developing mosquito oocytes, resulting in heritable gene editing of the offspring with efficiency as high as 0.3 mutants per injected mosquito. We demonstrate that P2C functions in six mosquito species. Identification of taxa-specific ovary-specific ligand–receptor pairs may further extend the use of ReMOT Control for gene editing in novel species.
Unravelling the age of fine roots of temperate and boreal forests
Authors: Solly Emily F. , Brunner Ivano , Helmisaari Heljä-Sisko , Herzog Claude , Leppälammi-Kujansuu Jaana , Schöning Ingo , Schrumpf Marion , Schweingruber Fritz H. , Trumbore Susan E. , Hagedorn Frank
Published: July 2018

Fine roots support the water and nutrient demands of plants and supply carbon to soils. Quantifying turnover times of fine roots is crucial for modeling soil organic matter dynamics and constraining carbon cycle–climate feedbacks. Here we challenge widely used isotope-based estimates suggesting the turnover of fine roots of trees to be as slow as a decade. By recording annual growth rings of roots from woody plant species, we show that mean chronological ages of fine roots vary from <1 to 12 years in temperate, boreal and sub-arctic forests. Radiocarbon dating reveals the same roots to be constructed from 10 ± 1 year (mean ± 1 SE) older carbon. This dramatic difference provides evidence for a time lag between plant carbon assimilation and production of fine roots, most likely due to internal carbon storage. The high root turnover documented here implies greater carbon inputs into soils than previously thought which has wide-ranging implications for quantifying ecosystem carbon allocation.
Author Correction: Direct measurement of superdiffusive energy transport in disordered granular chains
Authors: Kim Eunho , Martínez Alejandro J. , Phenisee Sean E. , Kevrekidis P. G. , Porter Mason A. , Yang Jinkyu
Published: July 2018

The original version of this Article contained an error in second sentence of the Acknowledgements, which incorrectly read ‘J.Y. and P.G.K. also acknowledge support from US-ARO (W911NF-15-1-0604) and US-AFOSR (FA9550-17-1-011), and P.G.K. also gratefully acknowledges support from the Stavros Niarchos Foundation via the Greek Diaspora Fellowship Program.’ The correct version states ‘US-AFOSR (FA9550-17-1-0114)’ in place of ‘US-AFOSR (FA9550-17-1-011)’. This has been corrected in both the PDF and HTML versions of the Article.
Simulating para-Fermi oscillators
Authors: Huerta Alderete C. , Rodríguez-Lara B. M.
Published: July 2018

Quantum mechanics allows for a consistent formulation of particles that are neither bosons nor fermions. These para-particles are rather indiscernible in nature. Recently, we showed that strong coupling between a qubit and two field modes is required to simulate even order para-Bose oscillators. Here, we show that finite-dimensional representations of even order para-Fermi oscillators are feasible of quantum simulation under weak coupling. This opens the door to their potential implementation in different contemporaneous quantum electrodynamics platforms. We emphasize the intrinsic value of para-particles for the quantum state engineering of bichromatic field modes. In particular, we demonstrate that binomial two field mode states result from the evolution of para-Fermi vacuum states in the quantum simulation of these oscillators.
Venom Complexity in a Pitviper Produced by Facultative Parthenogenesis
Authors: Calvete J. J. , Casewell N. R. , Hernández-Guzmán U. , Quesada-Bernat S. , Sanz L. , Rokyta D. R. , Storey D. , Albulescu L.-O. , Wüster W. , Smith C. F. , Schuett G. W. , Booth W.
Published: July 2018

Facultative parthenogenesis (FP) is asexual reproduction in plant and animal species that would otherwise reproduce sexually. This process in vertebrates typically results from automictic development (likely terminal fusion) and is phylogenetically widespread. In squamate reptiles and chondrichthyan fishes, FP has been reported to occur in nature and can result in the production of reproductively viable offspring; suggesting that it is of ecological and evolutionary significance. However, terminal fusion automixis is believed to result in near genome-wide reductions in heterozygosity; thus, FP seems likely to affect key phenotypic characters, yet this remains almost completely unstudied. Snake venom is a complex phenotypic character primarily used to subjugate prey and is thus tightly linked to individual fitness. Surprisingly, the composition and function of venom produced by a parthenogenetic pitviper exhibits a high degree of similarity to that of its mother and conspecifics from the same population. Therefore, the apparent loss of allelic diversity caused by FP appears unlikely to have a significant impact on the prey-capturing ability of this snake. Accordingly, the pitviper offspring produced by FP retained complex phenotypic characteristics associated with fitness. This result reinforces the potential ecological and evolutionary importance of FP and questions our understanding of the inheritance of venom-associated genes.