bluuebunny/crossref_metadata_2025 huggingface dataset:
Platelet-Rich Plasma Therapy for Male Sexual Dysfunction: Myth or Reality?
Authors: Epifanova Maya V. , Gvasalia Badri R. , Durashov Maksim A. , Artemenko Sergey A.
Published: March 2019

Introduction

Platelet-rich plasma (PRP) found its use in treating different conditions and diseases, because concentrated plasma PRP consists of many growth factors. Their interaction with surrounding cells, intracellular matrix, and mediators at the site of injection leads to tissue regeneration. Angiogenic, vasculogenic, and regenerative effects of PRP may be used for erectile dysfunction (ED) and Peyronie’s disease (PD) treatment.

Aim

To present a current data review of preclinical and clinical trials on PRP use for treating ED and PD.

Methods

Up-to-date literature on PRP use for ED and PD treatment was analyzed. The search was based on Pubmed, Cochrane Library, clinicaltrials.gov databases, with the following key words: “platelet-rich plasma” and/or “erectile dysfunction” and/or “Peyronie’s disease” and/or “sexual dysfunction.”

Main Outcome Measures

The main outcome measures for preclinical trials on ED were erectile function, assessed with intracavernous pressure, and pathologic analysis of penile tissue. The main outcome measures for clinical trials on ED included penile duplex Doppler ultrasound scanning and validated questionnaires. The main outcome measures on PD were pathologic analysis of penile tissue for preclinical trials, as well as penile duplex Doppler ultrasound scanning, penile curvature angle measuring, and validated questionnaires for clinical trials.

Results

4 preclinical and 6 clinical trials were described and analyzed in this article. Limitations for both preclinical and clinical trials included small groups, short follow-up periods, a lack of control groups or groups with placebo, and the lack of quality and quantity analysis of PRP.

Conclusion

Available data show the lack of adverse reactions with PRP treatment. The studies that we found were limited by small groups. This is why the data on safety and effectiveness should be taken carefully. However, it is important to mention that PRP therapy has the potential for treating male sexual dysfunction and may be useful in andrology.
Facial recognition as a force for good
Authors: Watts Rob
Published: March 2019

Facial recognition has become one of the most widely discussed technology solutions in recent years. Advocates such as myself point to its ability to make us all safer, to offer added convenience to users and to underpin operational efficiencies. Meanwhile critics tend to fall into one of two camps. They either claim it doesn't work, or conversely that it is an invasion of privacy and therefore a threat to society. Some of the concerns about how the technology is to be deployed are valid. However, history has almost always shown that those who seek to stand in the way of technological advancement find themselves on the wrong side of the debate.
Hegel on Reflection and Reflective Judgement
Authors: Miller Elaine P.
Published: March 2019

I examine the relation between logic and nature in terms of ‘reflection’, the word that Hegel uses at the end of theEncyclopaedia Logicto describe the self-sundering or externalization of the idea into nature. Although nominally the term ‘reflection’ seems to denote a uniquely mental process and is often used so by Hegel in his early critique ofReflexionsphilosophie, in his later writings it also has an irreducibly ontological significance. Hegel describes logic's opening-out to nature as a movement of ‘reflection’ [Widerschein] and he follows Kant in describing the shift from the finite to the infinite in the relation between nature and thought as one of reflective judgement. Although Hegel generally considers reflection to be uniquely concerned with finite cognition and the constitution of finite things, I argue that in his embrace of reflective judgement he sees a key role for reflection in the relation of logic, nature and spirit.
The prevalence of antiseptic tolerance genes among staphylococci and enterococci in a pediatric population
Authors: Sommer Lauren M. , Krauss Jennifer L. , Hultén Kristina G. , Dunn James J. , Kaplan Sheldon L. , McNeil J. Chase
Published: March 2019

Objective:

The smr and qacA/B genes in Staphylococcus aureus confer tolerance to antiseptics and are associated with nosocomial acquisition of infection and underlying medical conditions. Such antiseptic tolerance (AT) genes have also been reported in coagulase-negative staphylococci (CoNS) and enterococci, however, few data are available regarding their prevalence. We sought to describe the frequency of AT genes among bloodstream isolates of S. aureus, CoNS and enterococci at Texas Children’s Hospital (TCH).

Methods:

Banked CoNS, S. aureus and enterococci isolated from blood cultures collected bewteen October 1, 2016, and October 1, 2017, were obtained from the TCH clinical microbiology laboratory. All isolates underwent polymerase chain reaction (PCR) assay for the qacA/B and smr genes. Medical records were reviewed for all cases.

Results:

In total, 103 CoNS, 19 Enterococcus spp, and 119 S. aureus isolates were included in the study, and 80.6% of the CoNS possessed at least 1 AT gene compared to 37% of S. aureus and 43.8% of E. faecalis isolates (P < .001). Among CoNS bloodstream isolates, the presence of either AT gene was strongly associated with nosocomial infection (P < .001). The AT genes in S. aureus were associated with nosocomial infection (P = .025) as well as the diagnosis of central-line–associated bloodstream infection (CLABSI; P = .04) and recent hospitalizations (P < .001). We found no correlation with genotypic AT in E. faecalis and any clinical variable we examined.

Conclusions:

Antiseptic tolerance is common among bloodstream staphylococci and E. faecalis isolates at TCH. Among CoNS, the presence of AT genes is strongly correlated with nosocomial acquisition of infection, consistent with previous studies in S. aureus. These data suggest that the healthcare environment contributes to AT among staphylococci.
Advocacy for scaling up biofortified crops for improved micronutrient status in Africa: approaches, achievements, challenges and lessons
Authors: Omari Rose , Zotor Francis , Tagwireyi Julia , Lokosang Laila
Published: March 2019

Biofortification is an approach used to increase micronutrient content of crops through agronomic practices, conventional or modern biotechnology. Through a plethora of projects, partnerships were formed to advocate for policy changes, and increased investments in research, production and utilisation of biofortified crops. One of such projects is the Building Nutritious Food Baskets project, which has been appraised in order to draw and share successes, challenges and lessons for the improvement of similar future projects to achieve substantial impacts. The paper provides an overview of the role of biofortification in addressing nutritional challenges and highlights the efficacy of biofortified crops in improving micronutrient status. Through advocacy at the African Regional and sub-regional levels, awareness has been created on biofortification among governments, investors, development partners, farmers and consumers. This awareness has resulted in the incorporation of biofortification in some key policies, strategies and investment programmes. Key lessons learnt from regional advocacy are (1) in order to integrate biofortification in regional policies, strategies and programmes, it is important to identify champions from key and strategic regional organisations as they provide information on potential opportunities for influencing policies, (2) having a common advocacy message helps to highlight the role of biofortification in contributing to the prevention of micronutrient problems as well as evidence of impact on nutrition outcome, (3) champions need to be allocated a budget to support their advocacy work and (4) to engender adoption of biofortification, it is important to align biofortification with relevant initiatives as well as ongoing opportunities for advocacy.
Unpredictable homeodynamic and ambient constraints on irrational decision making of aneural and neural foragers
Authors: Clark Kevin B.
Published: March 2019

Foraging for nutritional sustenance represents common significant learned/heritable survival strategies evolved for phylum-diverse cellular life on Earth. Unicellular aneural to multicellular neural foragers display conserved rational or irrational decision making depending on outcome predictions for noise-susceptible real/illusory homeodynamic and ambient dietary cues. Such context-dependent heuristic-guided foraging enables optimal, suboptimal, or fallacious decisions that drive organismal adaptation, health, longevity, and life history.
Hope, exploration, and equilibrated action schemes
Authors: Gozli Davood G. , Gao Ci Jun
Published: March 2019

The concepts want, hope, and exploration cannot be organized in relation to a single type of motive (e.g., motive for food). They require, in addition, the motive for acquiring and maintaining a stable scheme that enables reward-directed activity. Facing unpredictability, the animal has to seek not only reward, but also a new equilibrated state within which reward seeking is possible.
Does the “incentive hope” hypothesis explain food-wasting behavior among humans? Yes and no
Authors: Misiak Michał , Sorokowski Piotr , Karwowski Maciej
Published: March 2019

In this commentary, we discuss how the “incentive hope” hypothesis explains differences in food-wasting behaviors among humans. We stress that the role of relevant ecological characteristics should be taken into consideration together with the incentive hope hypothesis: population mobility, animal domestication, and food-wasting visibility.
Household composition and the dynamics of community-based social care in England
Authors: Iparraguirre José
Published: March 2019

Little is known about the dynamic relationship between the different funding sources of community-based social care in England. Using Waves 2–6 (2004–2013) of the English Longitudinal Study of Ageing survey, I estimated dynamic multi-level cross-classified mixed-effects logistic regression models to investigate whether receiving services by one source is more or less likely if an older person was already receiving services funded by the same source or another in the previous period. Four hypotheses between formal privately and publicly funded help and informal help are tested: substitution, complementarity, compensation and task-specificity. I also report evidence that older people on low incomes residing in local authorities that reduce social care spending are especially affected.
‘That's for old so and so's!’: does identity influence older adults’ technology adoption decisions?
Authors: Astell Arlene J. , McGrath Colleen , Dove Erica
Published: March 2019

The role of identity in older adults’ decision-making about assistive technology adoption has been suggested but not fully explored. This scoping review was conducted to understand better how older adults’ self-image and their desire to maintain this influence their decision-making processes regarding assistive technology adoption. Using the five-stage scoping review framework by Arksey and O'Malley, a total of 416 search combinations were run across nine databases, resulting in a final yield of 49 articles. From these 49 articles, five themes emerged: (a) resisting the negative reality of an ageing and/or disabled identity; (b) independence and control are key; (c) the aesthetic dimension of usability; (d) assistive technology as a last resort; and (e) privacy versus pragmatics. The findings highlight the importance of older adults’ desire to portray an identity consistent with independence, self-reliance and competence, and how this desire directly impacts their assistive technology decision-making adoption patterns. These findings aim to support the adoption of assistive technologies by older adults to facilitate engagement in meaningful activities, enable social participation within the community, and promote health and wellbeing in later life.
Coriolis force-assisted inertial confinement fusion
Authors: Winterberg F.
Published: March 2019

A fundamental problem for the realization of laser fusion through the implosion of a spherical target is Kidder's E−1/6 law, where E is the energy needed for ignition, proportional to the 6th power of the ratio R/R0, where R0 and R are the initial and final implosion radii, respectively. This law implies that the ignition energy is very sensitive to the ratio R0/R, or vice versa, the ratio R0/R is very insensitive to the energy input, with R0/R limited by the Rayleigh–Taylor instability. According to still classified data of the Centurion–Halite experiment at the Nevada Test Site, ignition would require an energy of ${\rm E}\simeq 50\,{\rm MJ}$, 25 times larger than the 2 MJ laser at the National Ignition Facility (NIF) reported in the New York Times. This means that even a tenfold increase from 2 to 20 MJ would only decrease the R/R0 ratio by an insignificant factor of 10−1/6 ≃ 0.7. To overcome this problem, it is proposed that the spherical target is replaced with a hollowed-out, rapidly rotating, cm-size ferromagnetic target, accelerated by a rotating traveling magnetic wave to a rotational velocity of ~1 km/s, at the limit of its tensile strength. In a rotating reference system, the general theory of relativity predicts the occurrence of negative gravitational field masses in the center of rotation, with their source located in the Coriolis force field. The density of this negative gravitational field mass can be larger than the magnitude of the positive mass density of a neutron star. The repulsive gravitational force causes the centrifugal force. For a magnetized plasma placed in the rapidly spinning, hollowed-out target chamber, this repulsive force can be balanced by the magnetic force generated by thermomagnetic currents of the Nernst effect. Such a configuration does not suffer from the Rayleigh–Taylor instability, but becomes a small magnetohydrodynamic generator, amplifying the magnetic field to values about equal to those of the Nernst effect, axially confining the plasma. By placing the spinning target in the center of a lithium vortex, the fusion neutrons absorbed in the vortex can breed tritium, and at the same time remove heat from the target chamber to sustain the Nernst effect. A hot spot is thereby produced in the target chamber, which launches a thermonuclear burn wave into a cylindrical deuterium–tritium configuration. With the stability of a rapidly rotating target greatly increased, and the range of 10 MeV electrons in the wall of the cm-size ferromagnetic target, an intense 10 MeV relativistic electron beam drawn from a 10 MJ Marx generator should be sufficient to implode the target for thermonuclear ignition.
Surgery-induced cryptorchidism induces apoptosis and autophagy of spermatogenic cells in mice
Authors: Zheng Yi , Zhang Pengfei , Zhang Conghui , Zeng Wenxian
Published: March 2019

Cryptorchidism, characterized by the presence of one (unilateral) or both (bilateral) undescended testes, is a common male urogenital defect. Cryptorchidism can lead to male infertility, testicular cancer being the most extreme clinical symptom, as well as psychological issues of the inflicted individual. Despite this, both knowledge about the aetiology of cryptorchidism and the mechanism for cryptorchidism-induced male infertility remain limited. In this present study, by using an artificial cryptorchid mouse model, we investigated the effects of surgery-induced cryptorchidism on spermatogenic cells and seminiferous epithelial cycles. We found that surgery-induced cryptorchidism led to a reduced testicular weight, aberrant seminiferous epithelial cycles and impaired spermatogenesis characterized by degenerating spermatogenic cells. We also observed multinucleated giant cells after surgery-induced cryptorchidism. Transmission electron microscopy, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) and western blot assays demonstrated cryptorchidism-induced apoptosis of spermatogenic cells. Moreover, we identified the occurrence of autophagy in germ cells after surgery-induced cryptorchidism. Interestingly, apoptosis and autophagy were synchronous, suggestive of their synergetic roles in promoting germ cell death. Our results provide novel insights into the cryptorchidism-induced male infertility, thereby contributing to the development of male contraceptive strategies as well as treatment options for male infertility caused by cryptorchidism.
A SECOND-GENERATION STRUCTURALIST TRANSFORMATION PROBLEM: THE RISE OF THE INERTIAL INFLATION HYPOTHESIS
Authors: Roncaglia de Carvalho André
Published: March 2019

The paper analyzes the rise of the Latin American-based inertial inflation theory. Starting in the 1950s, various traditions in economics purported to explain the concept of “inflation inertia.” Contributions ranging from Celso Furtado and Mário Henrique Simonsen to James Tobin anticipated key aspects of what later became the inertial inflation hypothesis, building it into either mathematical or conceptual frameworks compatible with the then contemporaneous macroeconomic theory. In doing so, they bridged the analytical gap with the North American developments while maintaining the key features of the CEPAL (United Nations Economic Commission for Latin America and the Caribbean) approach, such as distributional conflicts and local institutional details. These contributions eventually influenced the second moment of the monetarist–structuralist controversy that unraveled in the 1980s. The paper also highlights how later works by structuralist economists gradually stripped the inertial inflation approach of its previous substance and form, thereby unearthing tensions among Latin American structuralists that led to the eventual decline of this research program.
Ingredient bundles and recipe tastings in food pantries: a pilot study to increase the selection of healthy foods
Authors: Stein Emma C , Stowers Kristen Cooksey , McCabe Michelle L , White Marney A , Schwartz Marlene B
Published: March 2019

Objective

The present study examined the effect of ingredient bundles (i.e. measured ingredients with recipes) and recipe tastings as a strategy to increase the selection of healthy, target foods (kale, brown rice and whole-wheat pasta).

Design

Each of the three conditions was tested once per week for three weeks. The conditions were: Treatment 1 (T1), recipe tastings only; Treatment 2 (T2), ingredient bundle plus recipe tastings; and Control, no intervention.

Setting

A food pantry in Bridgeport, CT, USA.

Participants

Food pantry clients.

Results

Controlling for family size and intervention week, the likelihood of clients in T2 (n 160) selecting at least one target item compared with the Control group (n 160) was 3·20 times higher for kale, 4·76 times higher for brown rice and 7·25 times higher for whole-wheat pasta. Compared with T1 (n 128), T2 clients were 2·67 times more likely to select kale, 7·67 times more likely to select brown rice and 11·43 times more likely to select whole-wheat pasta. No differences between T1 and the Control group were found.

Conclusions

Findings suggest that innovative, nudging strategies such as ingredient bundles may increase appeal of foods and encourage pantry clients to select healthier options.
Melt-water formed dark streaks on slopes of Haughton crater as possible Mars analogues
Authors: Clarke Jonathan , Knightly Paul , Rupert Shannon
Published: March 2019

Haughton crater in the Canadian Arctic has been extensively used as a Mars (and lunar) analogue over the past 20 years. Here we report on small scale, dark, semi-seasonal slope streaks formed by melt water flowing down the crater walls that we observed during the Mars Society-sponsored M160 expedition to the F-MARS facility on the NW rim of the crater. The streaks are formed by biofilms colonizing snow melt flowing from semi-permanent snow patches in Haughton crater on Devon Island and elsewhere in the Canadian Arctic. These features superficially resemble the dark slope streaks and recurring slope lineae (RSL) observed on Mars and may serve as analogues for wet models for their formation and a contrast with dry formation models. Their significance to astrobiology and planetary science is three-fold: (1) as examples of dark recurring streaks known to be associated with water they provide a benchmark to compare with Martian slope streaks and RSL. (2) The melt streaks may have potential as astrobiological analogues for wet models of slope streaks and RSL. (3) They are natural laboratories to study planetary protection issues associated with robotic and astronaut exploration of potential water-related slope features on Mars.
Paleometry as a key tool to deal with paleobiological and astrobiological issues: some contributions and reflections on the Brazilian fossil record
Authors: Gomes Amanda L. S. , Becker-Kerber Bruno , Osés Gabriel L. , Prado Gustavo , Becker Kerber Pedro , de Barros Gabriel E. B. , Galante Douglas , Rangel Elidiane , Bidola Pidassa , Herzen Julia , Pfeiffer Franz , Rizzutto Márcia A. , Pacheco Mírian L. A. F.
Published: March 2019

Investigations into the existence of life in other parts of the cosmos find strong parallels with studies of the origin and evolution of life on our own planet. In this way, astrobiology and paleobiology are married by their common interest in disentangling the interconnections between life and the surrounding environment. In this way, a cross-point of both sciences is paleometry, which involves a myriad of imaging and geochemical techniques, usually non-destructive, applied to the investigation of the fossil record. In the last decades, paleometry has benefited from an unprecedented technological improvement, thus solving old questions and raising new ones. This advance has been paralleled by conceptual approaches and discoveries fuelled by technological evolution in astrobiological research. In this context, we present some new data and review recent advances on the employment of paleometry to investigations on paleobiology and astrobiology in Brazil in areas such biosignatures in Ediacaran microbial mats, biogenicity tests on enigmatic Ediacaran structures, research on Ediacaran metazoan biomineralization, fossil preservation in Cretaceous insects and fish, and finally the experimental study on the decay of fish to test the effect of distinct types of sediment on soft-tissue preservation, as well as the effects of early diagenesis on fish bone preservation.
Measurement of Hedonic and Eudaimonic Orientations to Happiness: The Spanish Orientations to Happiness Scale
Authors: Lorente Laura , Tordera Núria , Peiró José María
Published: March 2019

Understanding happiness and well-being has been one of the central issues for psychologists in recent decades. Happiness orientations have been identified as important pathways toward different types of well-being, and so the development and validation of scales for their measurement is an important step in their study. The present research aims to adapt and validate the Spanish Orientations to Happiness Scale (SOTH), a 6-item scale based on the Orientations to Happiness Questionnaire. This brief scale, which measures hedonic and eudemonic orientations, was administered to 1,647 Spanish workers. Scale structure was subjected to exploratory (EFA) and confirmatory (CFA) factor analysis to obtain evidence of factorial validity. Evidence for convergent validity was assessed by correlating the scale with two measures of hedonic and eudaimonic well-being, and discriminant validity was assessed with the average variance extracted (AVE). Results of EFA showed a two-factor solution, and CFA partially supported this structure, χ2(8,N= 793) = 36.61, p < .001; RMSEA = .06; SRMR = .05; CFI = .97; ACFI = .96. Results also demonstrated appropriate convergent and discriminant validity. The SOTH Scale has been shown to be reliable (CR indices > .72) and valid (AVE = .50), and so it is a valuable tool for assessing orientations to happiness in the Spanish context. Finally, the scientific value and practical utility of the scale are discussed.
Coping, Social Support, and Suicide Attempts Among Homeless Adolescents
Authors: Gauvin Geoffrey , Labelle Réal , Daigle Marc , Breton Jean-Jacques , Houle Janie
Published: March 2019

Abstract. Background: Homeless youth are a population at risk for suicidal behavior. Despite growing knowledge about risk factors, protective factors against suicidal behavior among this population are still poorly understood. Aims: To explore differences in coping and social support between homeless adolescents who attempted suicide and those who did not. Method: In total, 76 homeless adolescents from eight different shelters provided information about their suicidal behaviors over the previous year and filled out coping and social support questionnaires. Results: Homeless adolescents who had not attempted suicide perceived more social support (tangible assistance and guidance). Conversely, youth who had attempted suicide reported using more nonproductive strategies of coping (tension reduction, keep to self, and self-blame). Tangible assistance and tension reduction were found to be the strongest predictors. Limitations: As most of these youth were not homeless for a long time, care should be taken in generalizing these results to adolescents with longer histories of homelessness. Conclusion: Productive coping does not seem to constitute a sufficient personal resource to protect homeless adolescents from suicide attempts. Nonproductive coping could, however, be considered a serious risk factor. Consequently, promoting homeless youths' ability to find environmental resources, especially tangible assistance, could be the most valuable approach.
Young People's Reasons for Feeling Suicidal
Authors: Ali Aamina , Gibson Kerry
Published: March 2019

Abstract. Background: While considerable attention has been given to explanations for youth suicide, less is known about the reasons that young people themselves give for suicidality. Research on online communications gives an opportunity to investigate the real-time reasons young people give for feeling suicidal. Aims: This study aimed to identify the reasons that young people provide for feeling suicidal in posts published on a suicide prevention forum, hosted on the social media platform Tumblr. Method: We filtered 2 months' worth of posts to identify those that related specifically to suicide. In total, 210 posts were thematically analyzed to identify the reasons given for suicidality and the meanings associated with these. Results: Six main reasons for suicidality were identified in the analysis: feeling lonely and socially disconnected, experiencing identity stigma, failing to meet expectations, being helpless, feeling worthless, and experiences of mental ill-health. Limitations: There are advantages as well as limitations associated with relying on Internet-based data. Limitations include the inability to establish participant demographics and the lack of context for posts. Conclusion: Suicide prevention efforts should target the reasons that young people give for feeling suicidal in the moment of crisis in order to engage this population more effectively.
Quantifying the Impact of Atmospheric Transport Uncertainty on CO2 Surface Flux Estimates
Authors: Schuh Andrew E. , Jacobson Andrew R. , Basu Sourish , Weir Brad , Baker David , Bowman Kevin , Chevallier Frédéric , Crowell Sean , Davis Kenneth J. , Deng Feng , Denning Scott , Feng Liang , Jones Dylan , Liu Junjie , Palmer Paul I.
Published: March 2019

We show that transport differences between two commonly used global chemical transport models, GEOS‐Chem and TM5, lead to systematic space‐time differences in modeled distributions of carbon dioxide and sulfur hexafluoride. The distribution of differences suggests inconsistencies between the transport simulated by the models, most likely due to the representation of vertical motion. We further demonstrate that these transport differences result in systematic differences in surface CO2 flux estimated by a collection of global atmospheric inverse models using TM5 and GEOS‐Chem and constrained by in situ and satellite observations. While the impact on inferred surface fluxes is most easily illustrated in the magnitude of the seasonal cycle of surface CO2 exchange, it is the annual carbon budgets that are particularly relevant for carbon cycle science and policy. We show that inverse model flux estimates for large zonal bands can have systematic biases of up to 1.7 PgC/year due to large‐scale transport uncertainty. These uncertainties will propagate directly into analysis of the annual meridional CO2 flux gradient between the tropics and northern midlatitudes, a key metric for understanding the location, and more importantly the processes, responsible for the annual global carbon sink. The research suggests that variability among transport models remains the largest source of uncertainty across global flux inversion systems and highlights the importance both of using model ensembles and of using independent constraints to evaluate simulated transport.
Evidence for Slip on a Border Fault Triggered by Magmatic Processes in an Immature Continental Rift
Authors: Jones J. Robert , Stamps D. Sarah , Wauthier Christelle , Saria Elifuraha , Biggs Juliet
Published: March 2019

Continental rifting evolves through repeated tectonic and magmatic processes. Here we investigate the 2007–2008 northern Tanzania rifting episode to understand the interactions between magmatism and border fault slip during immature continental rifting. We compare modeled stress changes with geodetic observations from the western adjacent border fault of the Natron basin. We model six distinct phases of the rifting episode, including the eruptive activity of Ol Doinyo Lengai. The southern portion of the border fault experienced a positive cumulative Coulomb stress change, consistent with newly processed Global Positioning System data showing a distinct instance of slip during this time period. Our work suggests active volcanism and faulting are correlated in time, indicating magmatism associated with volcanic activity influences slip on border faults in immature continental rifts.
EMIC Wave‐Driven Bounce Resonance Scattering of Energetic Electrons in the Inner Magnetosphere
Authors: Blum L.W. , Artemyev A. , Agapitov O. , Mourenas D. , Boardsen S. , Schiller Q.
Published: March 2019

While electromagnetic ion cyclotron (EMIC) waves have been long studied as a scattering mechanism for ultrarelativistic (megaelectron volt) electrons via cyclotron‐resonant interactions, these waves are also of the right frequency to resonate with the bounce motion of lower‐energy (approximately tens to hundreds of kiloelectron volts) electrons. Here we investigate the effectiveness of this bounce resonance interaction to better determine the effects of EMIC waves on subrelativistic electron populations in Earth's inner magnetosphere. Using wave and plasma parameters directly measured by the Van Allen Probes, we estimate bounce resonance diffusion coefficients for four different events, illustrative of wave and plasma parameters to be encountered in the inner magnetosphere. The range of electron energies and pitch angles affected is examined to better assess the realistic effects of EMIC‐driven bounce resonance on energetic electron populations based on actual, locally observed event‐based parameters. Significant local diffusion coefficients (~ > 10−6 s−1) for 50‐ to 100‐keV electrons are achieved for both H+ band wave events as well as He+ band, with diffusion coefficients peaking for near‐90° pitch angles but remaining elevated for intermediate ones as well. Diffusion coefficients for higher‐energy 200‐keV electrons are typically multiple orders of magnitude lower (ranging from 10−11 to 10−6 s−1) and often peak at lower pitch angles (~20–30°). These results suggest that both H+ and He+ band EMIC waves can play a role in shaping lower‐energy electron dynamics via bounce‐resonant interactions, in addition to their role in relativistic electron loss via cyclotron resonance.
Preferential Orthopyroxene Serpentinization and Implications for Seismic Velocity Interpretation in the Fore‐Arc Mantle
Authors: Nakatani T. , Nakamura M.
Published: March 2019

For better interpretation of seismic tomography data of the hydrated fore‐arc mantle, we examined conditions of nonstoichiometric hydration of peridotite reported by a previous experimental study (i.e., preferential orthopyroxene (Opx) serpentinization and resultant talc formation) at 500–580 °C and under 0.8–1.8 GPa. The corresponding seismic velocity was calculated by considering the talc production. Talc formed under all the experimental conditions even in the olivine‐dominated system, in which the olivine to Opx ratio was 7:3 by weight. The amount of talc produced was comparable to that of serpentine at high temperature and low pressure and increased with increasing temperature and decreasing pressure due to decreasing contribution of olivine in the reaction. We also present a natural case of preferential Opx reaction in the Horoman peridotite complex, Japan, on the basis of its strong similarity in textures and mineral phases to our experimental products obtained at 0.8–1.3 GPa. Calculations on seismic velocities of hydrated harzburgite using the Voigt‐Reuss‐Hill averaging scheme showed that the formation of talc along with antigorite leads to a decrease in P wave (Vp) and S wave velocities (Vs) but no remarkable increase in Vp/Vs due to the lower Vp/Vs value of talc (~1.60) compared with that of antigorite (~1.77). Such a seismic anomaly has been observed in the shallow mantle wedge of the southern Western Alps subduction zone, where suppressed water supply from the subducted continental lithosphere might allow the persistence of talc produced by the preferential Opx reaction.
Sea Surface Salinity Distribution in the Southern Ocean as Observed From Space
Authors: Garcia‐Eidell Cynthia , Comiso Josefino C. , Dinnat Emmanuel , Brucker Ludovic
Published: March 2019

Large‐scale spatial and temporal variabilities of sea surface salinity (SSS) in the Southern Ocean from 2011 to 2017 were studied using products derived from microwave sensors on board Aquarius, Soil Moisture and Ocean Salinity (SMOS), and Soil Moisture Active and Passive (SMAP) satellites. Four products, three from Aquarius and one from SMOS, were evaluated and shown to be generally consistent within 0.3 to 0.6 psu and agree favorably with in situ measurements. However, although the Aquarius products show consistent seasonality of SSS with high values of 34.45 psu in October and low values of 33.40 psu in May, the SMOS and SMAP products lack such seasonal variations. This may be caused by larger uncertainties in the SMOS and SMAP data due in part to the lack of concurrent scatterometer measurements that is used to correct for roughness effects. The four products provide similar spatial distributions of SSS with root‐mean‐square difference from 0.25 to 0.58 psu. Differences among Aquarius products are mainly due to varying salinity retrieval algorithms, smoothing, and masking of sea ice, while the SMOS product showed the highest SSS deviation that is likely due to the bias‐adjustment done on the data set. Our analyses show that SSS in the Southern Ocean region has significant meridional variations with the lowest SSS near the ice edge and highest at lower latitudes. The SSS is also lowest in summer indicating the predominant influence of sea ice and glacial melt, but it stays low near ice edges even during the growth season.
A Comparison of the Atlantic and Pacific Bjerknes Feedbacks: Seasonality, Symmetry, and Stationarity
Authors: Dippe T. , Lübbecke J. F. , Greatbatch R. J.
Published: March 2019

The Bjerknes feedback is the dominant positive feedback in the equatorial ocean basins. To examine the seasonality, symmetry, and stationarity of the Pacific and Atlantic Bjerknes feedbacks we decompose them into three feedback elements that relate thermocline depth, sea surface temperature, and western basin wind stress variability to each other. We partition feedback elements into composites associated with positive or negative anomalies. Using robust regression, we diagnose the strength of each composite. For the recent period 1993–2012, composites of the Pacific Bjerknes feedback elements agree well with previous work. Positive composites are generally stronger than negative composites, and all feedback elements are weakest in late boreal spring. In the Atlantic, differences between positive and negative composites are less consistent across feedback elements. Specifically, wind variability seems to play a less important role in shaping atmosphere‐ocean coupling in the Atlantic when compared to the Pacific. However, a clear seasonality emerges: Feedback elements are generally strong in boreal summer and, for the negative composites, again in boreal winter. The Atlantic Bjerknes feedback is dominated by subsurface‐surface coupling. Applying our analysis to overlapping 25‐year periods for 1958–2009 shows that the strengths of feedback elements in both ocean basins vary on decadal time scales. While the overall asymmetry of the Pacific Bjerknes feedback is robust, the strength and symmetry of Atlantic feedback elements vary considerably between decades. Our results indicate that the Atlantic Bjerknes feedback is nonstationary on decadal time scales.
Plant Feedback Aggravates Soil Organic Carbon Loss Associated With Wind Erosion in Northwest China
Authors: Lei Lingjie , Zhang Kesheng , Zhang Xuanze , Wang Ying‐Ping , Xia Jianyang , Piao Shilong , Hui Dafeng , Zhong Mingxing , Ru Jingyi , Zhou Zhenxing , Song Hongquan , Yang Zhongling , Wang Dong , Miao Yuan , Yang Fan , Liu Bin , Zhang Ang , Yu Mengyang , Liu Xianghui , Song Yongheng , Zhu Lili , Wan Shiqiang
Published: March 2019

Soil organic carbon (SOC) loss caused by wind erosion can profoundly impact carbon (C) balance in arid and semiarid regions. Nevertheless, previous researches mainly focused on the direct effect of wind erosion through removing surface soil only but ignored its indirect effects associated with soil nitrogen (N) loss and subsequent reductions of plant productivity. To better understand the wind erosion effect on SOC storage, we conducted a large‐scale field experiment by manipulating wind erosion at 371 sites in arid and semiarid regions of northwest China from 2014 to 2016. We further integrated an observation‐based empirical equation of wind erosion process into a terrestrial biogeochemical model to evaluate the direct and indirect effects of wind erosion on SOC storage in northwest China. The observed results showed that direct SOC losses increased linearly with the square of wind speed but decreased nonlinearly with soil water content. Over the 34 years (1980–2013), simulated cumulative SOC losses associated with wind erosion in northwest China were 27.47 Tg C, among which the indirect effects contributed to 2.68 Tg C (9.76%). The indirect effect of wind erosion initially enhanced SOC storage by decreasing heterotrophic respiration from 1984 to 1988 but decreased SOC pool by reducing net primary productivity due to soil N loss under the long‐term wind erosion scenario. This work, for the first time, quantified the indirect impact of wind erosion on SOC storage via feedback of suppressed plant productivity, which is crucial for the convincing assessment on SOC storage in arid and semiarid regions.
Aerosol‐Cloud‐Precipitation Interactions in the Context of Convective Self‐Aggregation
Authors: Beydoun H. , Hoose C.
Published: March 2019

We investigate the sensitivity of self‐aggregated radiative‐convective‐equilibrium cloud‐resolving model simulations to the cloud condensation nuclei (CCN) concentration. Experiments were conducted on a long (2,000‐km × 120‐km) channel domain, allowing the emergence of multiple convective clusters and dry regions of subsidence. Increasing the CCN concentration leads to increased moisture in the dry regions, increased midlevel and upper level clouds, decreased radiative cooling, and decreased precipitation. We find that these trends follow from a decrease in the strength of the self‐aggregation as measured by the moist static energy (MSE) variance. In our simulations, precipitation is correlated, both locally and in total, with the distribution of MSE anomalies. We thus quantify changes in the adiabatic/diabatic contributions to MSE anomalies (Wing & Emanuel, 2014, https://doi.org/10.1002/2013MS000269) and relate those changes to changes in precipitation. Through a simple two‐column conceptual model, we argue that the reduction in precipitation can be explained thermodynamically by the reduction in mean net radiative cooling and mechanistically by the weakening of the area‐weighted radiatively driven subsidence velocity—defined as the ratio of the total radiative cooling over the dry regions and the static stability. We interpret the system's response to increasing CCN as a thermodynamically constrained realization of an aerosol indirect effect on clouds and precipitation.
Thermotectonic Evolution of the North Pyrenean Agly Massif During Early Cretaceous Hyperextension Using Multi‐mineral U‐Pb Thermochronometry
Authors: Odlum M. L. , Stockli D. F.
Published: March 2019

The North Pyrenean Zone represents a fossil hyperextended passive margin, with limited orogenic overprinting, where the thermal and structural patterns associated with crustal thinning and mantle exhumation can be studied on rocks exposed at the surface. The Agly Massif is a tilted ~10‐km‐thick crustal section of Paleozoic and upper Proterozoic magmatic and greenschist to granulitic metamorphic rocks in the easternmost North Pyrenean Zone. We applied multi‐mineral geochronometry and thermochronometry on structural/crustal transects across the massif to understand the exhumation history of the upper and lower continental crust during extreme crustal thinning and mantle exhumation. Integration of zircon and apatite U‐Pb ages provides unprecedented constraints to understand the decoupled versus coupled extensional evolution, exhumation timing of the middle‐lower crust, and the age of juxtaposition of the upper crust granitic pluton with high‐grade gneisses. The Saint Arnac pluton was emplaced and cooled in the upper crust during the Carboniferous and remained at temperatures between 450 and 180 °C until the Late Cretaceous. The middle to lower crust was metamorphosed during the Carboniferous and remained at temperatures >450 °C until the Aptian, when it was rapidly exhumed along a midcrustal shear zone. Deformation was initially decoupled along a midcrustal ductile shear zone until the whole massif was in the brittle field, with structural juxtaposition of the units, and exhumation was coupled and controlled by a major southward dipping detachment fault at the southern border of the massif. The basement massif and synrift sedimentary rocks record significantly different thermal histories during rifting.
Ecuador’s El Reventador Volcano Continually Remakes Itself
Authors: Almeida Marco , Gaunt H. , Ram�n Patricio
Published: March 2019

A research team from Ecuador’s Geophysical Institute keeps a close eye on an unusually active and unstable volcano in the nation’s remote jungles.
Strategies to Improve Urban Hydrology
Authors: Sidder Aaron
Published: March 2019

Cities can reduce surface runoff and increase groundwater recharge by encouraging their residents to implement simple, hydrologic modifications on individual buildings and single-family parcels.
Climatic Controls on Landscape Dissection and Network Structure in the Absence of Vegetation
Authors: Hooshyar Milad , Singh Arvind , Wang Dingbao , Foufoula‐Georgiou Efi
Published: March 2019

Drainage networks emerge due to the movement of sediment driven by climatic and tectonic forcings. Previous observations revealed the dependence of drainage density (Dd) on climatic factors such as mean annual precipitation (MAP). Specifically, it has been observed in intermediate climate (~175 mm < MAP < 700 mm) that Dd decreases with increasing MAP. This declining trend has been argued to be attributed to biotic activity, that is, the dominance of vegetation growth over runoff erosive force. Using high‐resolution topographic data from a physical experiment, we show that increasing rainfall may result in decreasing Dd even in the absence of biotic activity. Increasing rainfall rate results in narrower and less variable bifurcation angle and relatively longer links. The response of the evolving network in terms of bifurcation angle continues beyond the time when Dd has reached a new stable value, indicating that the network's topological response is relatively slower than the geomorphic response.
Prediction of Reservoir Storage Anomalies in India
Authors: Tiwari Amar Deep , Mishra Vimal
Published: March 2019

Reservoirs provide water for irrigation and hydropower and protect downstream regions from flooding. Reservoir storage is affected by drought, which hampers the ability to provide water for irrigation and hydropower. Despite the need for reservoir storage prediction for planning and decision‐making, a reservoir storage forecast system at 1‐ to 3‐month lead has been lacking for major reservoirs in India. Here we evaluate the potential of observed accumulated precipitation, standardized precipitation index (SPI), standardized precipitation evapotranspiration index (SPEI), standardized streamflow index (SSI), and observed reservoir storage to provide reservoir storage anomaly forecast at 1‐ to 3‐month lead for the dry season (February to May) using a statistical approach. We find that accumulated precipitation for 3–11 months is strongly associated with the monthly reservoir storage anomalies in India. Moreover, accumulated precipitation and observed reservoir storage provide a reasonable (R2 = 0.7) forecast skill for reservoir storage anomalies at 1‐ to 3‐month lead. Similarly, SPI and SPEI can be used to predict reservoir storage anomalies at 1‐ to 3‐month lead in India. Since the prediction skill from SPI and SPEI is similar, reservoir storage at monthly timescale is largely affected by accumulated precipitation instead of variability in air temperature. We find that the forecast skill for the 1‐month lead from SPI, SPEI, and SSI is similar for Indira Sagar (Narmada) and Minimata (Mahanadi) reservoirs; however, prediction skill for reservoir storage anomalies improves substantially using SSI for 2‐ to 3‐month lead. Reservoir storage anomalies forecast at 1‐to 3‐month lead can be valuable for water management‐related decision‐making and planning during the dry season in India.
Net Ecosystem Carbon Balance of a Peat Bog Undergoing Restoration: Integrating CO2 and CH4 Fluxes From Eddy Covariance and Aquatic Evasion With DOC Drainage Fluxes
Authors: D′Acunha Brenda , Morillas Laura , Black T. Andrew , Christen Andreas , Johnson Mark S.
Published: March 2019

Peatland ecosystems are generally carbon (C) sinks. However, the role of dissolved organic C (DOC) relative to gaseous fluxes of CO2 and CH4 in the C balance of these ecosystems has not often been studied. Dissolved C fluxes are important for understanding C partitioning within the peatland and the potential C drainage from it. This research was conducted in Burns Bog, a heavily impacted ecosystem near Vancouver, Canada, undergoing ecological restoration efforts by rewetting. Here we present data on (i) ecosystem‐scale fluxes of CO2 (net ecosystem exchange, NEE) and CH4 (FCH4) determined by eddy covariance, (ii) evasion fluxes of CO2 and CH4 from the water surface to estimate the role of open water in ecosystem‐scale fluxes, and (iii) DOC flux (fDOC) in water draining from the peatland. Our results showed that open water areas inside the footprint were a continual C source, emitting 47.0 ± 2.4 g C·m−2·year−1. DOC export (15.6 g C·m−2·year−1) was significant to the net ecosystem C balance, decreasing the magnitude of the eddy covariance‐determined C balance (i.e., NEE + FCH4) of −45.0 ± 16.8 g C·m−2·year−1 by 35%, resulting in a net ecosystem C balance (i.e., NEE + FCH4 + fDOC) of −29.7 ± 17.0 g C·m−2·year−1. Most of this offset occurred during the wetter nongrowing season when gross primary production was low and fDOC was relatively high.