bluuebunny/crossref_metadata_2025 huggingface dataset:
Spoken word processing in Rett syndrome: Evidence from event‐related potentials
Authors: Key Alexandra P. , Jones Dorita , Peters Sarika
Published: January 2019

This study examined the feasibility of using auditory event‐related potentials to evaluate spoken word processing during passive listening in girls with Rett syndrome (n = 11) and typical peers (n = 33), age 4–12 years. The typical group demonstrated the expected pattern of more negative amplitudes within 200–500 ms in response to words than nonwords at left temporal sites. In participants with Rett syndrome, word‐nonword differentiation was observed at the right temporal sites. More negative left hemisphere amplitudes in response to words were associated (at trend level) with better receptive language skills and more adaptive behavior. The results indicate that girls with Rett syndrome differentiate known words from novel nonwords, but may do so using potentially atypical neural processes. Brain‐behavior correlations support validity of the proposed neural markers of word processing, making passive listening paradigms a promising approach for assessing speech and language processing in participants with limited spoken language skills.
The placenta as a window to the brain: A review on the role of placental markers in prenatal programming of neurodevelopment
Authors: Shallie Philemon Dauda , Naicker Thajasvarie
Published: January 2019

Background

During development, the placenta can be said to be the most important organ, however, the most poorly researched. There is currently a broader understanding of how specific insults during development affect the fetal brain, and also the importance of placental signaling in neurodevelopmental programming. Epigenetic responses to maternal and fetal signals are an obvious candidate for transforming early life inputs into long‐term programmatic outcomes. As a mediator of maternal and environmental signals to the developing fetus, epigenetic processes within the placenta are particularly powerful such that alterations of placental gene expression, downstream function, and signalling during foetal development have the potential for dramatic changes in developmental programming.

In this article, we reviewed emerging evidence for a placental role in prenatal neurodevelopmental programming with a specific focus on nutrient and prenatal stress signals integration into chromatin changes; this new understanding, we hope will provide the means for lowering developmentally based disorder risk, and new therapeutic targets for treatment in adulthood.

Key messages

Based on this review, the placenta is a potent micro‐environmental player in neurodevelopment as it orchestrates a series of complex maternal–foetal interactions. Maternal insults to this microenvironment will impair these processes and disrupt foetal brain development resulting in the prenatal programming of neurodevelopmental disorders. These findings should inspire advance animal model and human research drive to appraise gene–environment impacts during pregnancy that will target the developmental cause of adult‐onset mental disorders.
Exosomes populate the cerebrospinal fluid of preterm infants with post‐haemorrhagic hydrocephalus
Authors: Spaull Robert , McPherson Bryony , Gialeli Andriana , Clayton Aled , Uney James , Heep Axel , Cordero‐Llana Óscar
Published: January 2019

Background

Preterm infants are at risk of germinal matrix haemorrhage‐intraventricular haemorrhage (GMH‐IVH) which leads to post‐haemorrhagic hydrocephalus (PHH) in 30% of infants; this is associated with moderate‐severe neurodevelopmental impairment and confers significant risk of cerebral palsy. There are however no predictive indicators of the severity or long‐term outcome after GMH‐IVH. In recent years, endosome‐derived extracellular vesicles (EVs) or exosomes have been isolated from biofluids and shown to mediate intercellular communication via selective enrichment in proteins and micro‐RNAs.

Methods

This study aimed to isolate and characterise EVs from the cerebrospinal fluid (CSF) of 3 preterm infants with PHH using nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM) with immunogold protein labelling, and micro‐RNA analysis.

Results

NTA of unaltered CSF revealed a heterogeneous and dynamic population of EVs. Exosomal‐sized EVs were isolated by differential ultracentrifugation and TEM confirmed the presence of CD63+ and CD81+ exosomes. The micro‐RNAs miR‐9, miR‐17, miR‐26a, miR‐124 and miR‐1911 were detected within the exosome‐enriched fraction and profiled over time.

Conclusion

This is the first reported characterisation of exosomes from the CSF of preterm infants with post‐haemorrhagic hydrocephalus.
Sexual Health Problems and Discussion in Colorectal Cancer Patients Two Years After Diagnosis: A National Cross-Sectional Study
Authors: Almont T. , Bouhnik A.-D. , Ben Charif A. , Bendiane M.-K. , Couteau C. , Manceau C. , Mancini J. , Huyghe É.
Published: January 2019

Background

Colorectal cancer (CRC) is accompanied by specific treatment-related physical (ostomy, incontinence) and psychosexual (body image, depression) consequences on sexual health.

Aim

To assess sexual health of patients with CRC 2 years after diagnosis.

Methods

We selected all patients with CRC from a French nationwide longitudinal study. Data sources included patient questionnaires, medical questionnaires, and medico-administrative databases.

Main Outcome Measure

We evaluated sexual health using the Relationship and Sexuality Scale and assessed self-reported rates of discussion about sexuality with health care providers.

Results

Across the 487 patients, 258 were men and 229 were women; 77% were diagnosed with colon cancer and 23% with rectal cancer. Overall, 54% of patients reported a decrease in sexual desire, 61% a decrease in frequency of intercourse, and 48% a decrease in the possibility to reach an orgasm. Patients still experiencing fecal incontinence 2 years after diagnosis had decreases in all sexual desire, intercourse, orgasm, and satisfaction Relationship and Sexuality Scale items. Patients with rectal cancer had significantly more frequent troubles with desire and orgasm than did patients with colon cancer (P = .003 and P = .014, respectively). Regarding the discussion about sexuality, only 20% of men, 11% of women, 11% of patients with colon cancer, and 33% of patients with rectal cancer recalled having discussed sexuality with the medical team. Factors independently increasing the chance to have discussed sexuality with the medical team were younger age (odds ratio [OR] = 2.77 [1.31; 5.84]; P = .007), having an ostomy (OR = 2.93 [1.27; 6.73]; P = .011), and radiotherapy (OR = 2.78 [1.23; 6.27]; P = .014).

Clinical Implications

These results highlight the need for developing interventions to improve information delivery at cancer announcement and for managing sexual troubles during survivorship in patients with CRC, particularly those experiencing fecal incontinence.

Strength & Limitations

Strengths are the sample size and the national representation using the data of a large-scale nation-wide survey, with the possibility of comparing colon and rectal cancers. Limitations are the assessment of sexuality 2 years after diagnosis and using only self-reported measures.

Conclusion

This study highlights the lack of discussion about sexuality with the oncology team and the need for specific sexual rehabilitation interventions, especially for patients with rectal cancer and fecal incontinence. Developing these aspects may help patients with CRC improve their sexual prognosis.
First Outcomes of the ZSI 475 FtM, a Specific Prosthesis Designed for Phalloplasty
Authors: Neuville Paul , Morel-Journel Nicolas , Cabelguenne Delphine , Ruffion Alain , Paparel Philippe , Terrier Jean-Etienne
Published: January 2019

Introduction

The ZSI 475FtM is a new prosthesis that has recently been specifically designed for phalloplasty. It has several functions that have been conceived to answer the challenges of implantation after phalloplasty: a large base for pubic bone fixation, realistically shaped hard glans, and a pump shaped like a testicle.

Aim

To assess the safety, feasibility, and patient satisfaction of the ZSI 475 FtM.

Methods

Surgical outcomes were analyzed after implantation of the prosthesis between June 2016 and September 2017 (single institution, single surgeon). Patients were then asked to answer a satisfaction questionnaire that included the International Index of Erectile Function–5, Erectile Dysfunction Inventory of Treatment Satisfaction, and Self-Esteem and Relationship, as well as other non-validated questions.

Main Outcome Measure

Complication rates and the scores of the different questionnaires were reviewed.

Results

20 patients who had gender dysphoria and underwent operation for a female-to-male procedure were included. The mean age was 37.9 years. Complications after 21 implantations included 2 (9.5%) infections that were medically treated (Clavien II), 1 (4.7%) infection treated by explantation (Clavien IIIb), 2 (9.5%) mechanical failures (Clavien IIIb), and 1 (4.7%) malpositioning (Clavien IIIb). The mean follow-up was 8.9 months (SD 4.0), with 50% of the implanted patients having >12 months of follow-up. 14 patients (70%) answered the satisfaction questionnaire. 12 patients (85.7%) had regular penetrative sexual intercourse. The mean International Index of Erectile Function–5 score was 20.2 of 25 (standard deviation [SD] 7.9), the mean Self-Esteem and Relationship score was 84.5 of 100 (SD 9.9), and the mean Erectile Dysfunction Inventory of Treatment Satisfaction score was 82 of 100 (SD 17.5). 13 patients (92.8%) were satisfied or very satisfied with the prosthesis.

Clinical Implications

This new innovative prosthesis could better answer the challenges faced by the implantation of an erectile device by phalloplasty.

Strength & Limitations

Our study is the first to report data on this new prosthesis. The main limitation is the small number of patients and the short follow-up.

Conclusion

Preliminary results for the ZSI 475 FtM are encouraging. Safety seems to be satisfactory, and patient satisfaction is high. Long-term studies are needed for further analysis.
The structure and properties formation in iron–carbon powder composite materials during infiltration
Authors: Dyachkova L.N. , Vityaz P.A.
Published: January 2019

This paper describes some properties and structure formation features of the MMCs obtained by the infiltration of iron–carbon skeletons with tin bronze. It has been shown that the formation of the MMC structure depends on the composition and porosity of the iron skeleton. During the infiltration of a green skeleton, a redistribution of carbon and nickel occurs; outer layers have less carbon and more nickel; and carbon content is higher in the centre of the particles. With higher carbon content of the iron skeleton, the hardness and wear resistance properties of MMCs increase. The strength and wear resistance properties of the MMCs obtained by the infiltration of a green skeleton are higher compared to the sintered one regardless of the carbon content in the skeleton.
Long-term Effects of Disasters on Health Care Utilization: Hurricane Katrina and Older Individuals with Diabetes
Authors: Quast Troy , Feng Lijuan
Published: January 2019

Objective

While the short-term effects of disasters on health care utilization are well documented, less is known regarding potential longer-term effects. This study investigates the effects of Hurricane Katrina on the health care utilization of older individuals with diabetes.

Methods

We examined Medicare claims and enrollment data for the 2002-2004 and 2006-2008 time periods for older individuals with diabetes. Our quasi-experimental design analyzed utilization across 2 treated and 3 control groups. We compared the proportion of individuals who received a screen related to diabetes before and after Katrina in the treated groups to the proportions in the control groups. Our regression analysis employs individual and year fixed effects to control for factors specific to a given individual or to a given year.

Results

We found that utilization rates in the 2002-2004 period exhibited roughly parallel trends for the treated and control groups, which provides support for our research design. The 2006-2008 utilization rates were generally lower for the treated groups than they were for the control groups. The differences were especially pronounced for older age cohorts.

Conclusions

Our study suggests that the effects of disasters on health care utilization may persist for years after the event. Recovery efforts may be improved by addressing both short-term and long-term health care interruptions. (Disaster Med Public Health Preparedness. 2019;13:724–731)
Comparison of the growth performance and long-chain PUFA biosynthetic ability of the genetically improved farmed tilapia (Oreochromis niloticus) reared in different salinities
Authors: You Cuihong , Lu Fangbin , Wang Shuqi , Chen Cuiying , Li Yuanyou
Published: January 2019

To compare the growth and biosynthetic ability of long-chain PUFA (LC-PUFA) of the genetically improved farmed tilapia (GIFT) (Oreochromis niloticus) in different water salinities, an 8-week feeding trial was conducted on the GIFT juveniles at 0, 12 and 24 ‰ (parts per thousand; ppt), respectively, with three isonitrogenous (32 %) and isolipidic (8 %) diets (D1–D3). Diet D1 with fish oils (rich in LC-PUFA) as lipid source was used as the control, while D2 and D3 with vegetable oil (free LC-PUFA) blends as lipid source contained different ratios of linoleic acid (LA, 18 : 2n-6) and α-linolenic acid (ALA, 18 : 3n-3) at 4·04 (D2) and 0·54 (D3), respectively. At the end of feeding trial, the growth performance of D2 and D3 groups under all salinity treatments was as good as that of D1 group, which indicates that the GIFT juveniles may convert dietary LA and ALA into LC-PUFA to meet the requirement of essential fatty acids for normal growth and physiology. When fed the same diets, GIFT at 12 ppt had a better growth performance coupled with a higher liver and muscle arachidonic acid content than those in freshwater. Furthermore, brackish water (24 ppt) significantly promoted the mRNA levels of elongase 5 of very long-chain fatty acids (elovl5) and peroxisome proliferator-activated receptor α (pparα) in liver, when compared with freshwater. These results suggest that the GIFT may display better growth performance together with a relatively higher endogenous LC-PUFA biosynthetic ability under brackish water (12 and 24 ppt), probably through improving the expression of elovl5 and pparα in liver.
A Palaeoproterozoic basement beneath the Rangnim Massif revealed by the in situ U–Pb ages and Hf isotopes of xenocrystic zircons from Triassic kimberlites of North Korea
Authors: Zhu Yu-Sheng , Yang Jin-Hui , Wang Hao , Wu Fu-Yuan
Published: January 2019

In situ U–Pb and Hf analyses were used for crustal zircon xenocrysts from Triassic kimberlites exposed in the Rangnim Massif of North Korea to identify components of the basement hidden in the deep crust of the Rangnim Massif and to clarify the crustal evolution of the massif. The U–Pb age spectrum of the zircons has a prominent population at 1.9–1.8 Ga and a lack of Archaean ages. The data indicate that the deep crust and basement beneath the Rangnim Massif are predominantly of Palaeoproterozoic age, consistent with the ages of widely exposed Palaeoproterozoic granitic rocks. In situ zircon Hf isotope data show that most of the Palaeoproterozoic zircon xenocrysts have negative ϵHf(t) values (−9.7 to +0.7) with an average Hf model age of 2.86 ± 0.02 Ga (2σ), which suggests that the Palaeoproterozoic basement was not juvenile but derived from the reworking of Archaean rocks. Considering the existence of Archaean remanent material in the Rangnim Massif and their juvenile features, a strong crustal reworking event is indicated at 1.9–1.8 Ga, during which time the pre-existing Archaean basement was exhausted and replaced by a newly formed Palaeoproterozoic basement. These features suggest that the Rangnim Massif constitutes the eastern extension of the Palaeoproterozoic Liao–Ji Belt of the North China Craton instead of the Archaean Liaonan Block as previously thought. A huge Palaeoproterozoic orogen may exist in the eastern margin of the Sino-Korean Craton.
Appointments and attrition: time and executive disadvantage in the appointments process
Authors: Hollibaugh Gary E. , Rothenberg Lawrence S.
Published: January 2019

While the importance of political appointments is a matter of consensus, theorists and empiricists generally focus on different considerations, such as ideology and confirmation duration, respectively. More recently, there have been efforts to integrate empirical and theoretical scholarship but, to date, no empirical analysis assesses theoretical expectations about the relationship between temporal concerns and nominee ideologies. We fill this gap by examining theoretical predictions and related expectations about how the passage of time affects the President’s choices of nominees. We find that executives are disadvantaged as days pass and Presidents propose nominees with whom they are less ideologically compatible over time.
Data preprocessing in predictive data mining
Authors: Alexandropoulos Stamatios-Aggelos N. , Kotsiantis Sotiris B. , Vrahatis Michael N.
Published: January 2019

A large variety of issues influence the success of data mining on a given problem. Two primary and important issues are the representation and the quality of the dataset. Specifically, if much redundant and unrelated or noisy and unreliable information is presented, then knowledge discovery becomes a very difficult problem. It is well-known that data preparation steps require significant processing time in machine learning tasks. It would be very helpful and quite useful if there were various preprocessing algorithms with the same reliable and effective performance across all datasets, but this is impossible. To this end, we present the most well-known and widely used up-to-date algorithms for each step of data preprocessing in the framework of predictive data mining.
Asymptotic approximations for the plasmon resonances of nearly touching spheres
Authors: SCHNITZER O.
Published: January 2019

Excitation of surface-plasmon resonances of closely spaced nanometallic structures is a key technique used in nanoplasmonics to control light on subwavelength scales and generate highly confined electric-field hotspots. In this paper, we develop asymptotic approximations in the near-contact limit for the entire set of surface-plasmon modes associated with the prototypical sphere dimer geometry. Starting from the quasi-static plasmonic eigenvalue problem, we employ the method of matched asymptotic expansions between a gap region, where the boundaries are approximately paraboloidal, pole regions within the spheres and close to the gap, and a particle-scale region where the spheres appear to touch at leading order. For those modes that are strongly localised to the gap, relating the gap and pole regions gives a set of effective eigenvalue problems formulated over a half space representing one of the poles. We solve these problems using integral transforms, finding asymptotic approximations, singular in the dimensionless gap width, for the eigenvalues and eigenfunctions. In the special case of modes that are both axisymmetric and odd about the plane bisecting the gap, where matching with the outer region introduces a logarithmic dependence upon the dimensionless gap width, our analysis follows Schnitzer [Singular perturbations approach to localized surface-plasmon resonance: nearly touching metal nanospheres. Phys. Rev. B92(23), 235428 (2015)]. We also analyse the so-called anomalous family of even modes, characterised by field distributions excluded from the gap. We demonstrate excellent agreement between our asymptotic formulae and exact calculations.
Health Care Provision During a Sporting Mass Gathering: A Structure and Process Description of On-Site Care Delivery
Authors: Johnston Amy N. B. , Wadham Jasmine , Polong-Brown Josea , Aitken Michael , Ranse Jamie , Hutton Alison , Richards Brent , Crilly Julia
Published: January 2019

Introduction

Mass gatherings such as marathons are increasingly frequent. During mass gatherings, the provision of timely access to health care services is required for the mass-gathering population, as well as for the local community. However, the nature and impact of health care provision during sporting mass gatherings is not well-understood.

Purpose

The aim of this study was to describe the structures and processes developed for an emergency health team to operate an in-event, acute health care facility during one of the largest mass-sporting participation events in the southern hemisphere, the Gold Coast Marathon (Queensland, Australia).

Methods

A pragmatic, qualitative methodology was used to describe the structures and processes required to operate an in-event, acute health care facility providing services for marathon runners and spectators. Content analysis from 12 semi-structured interviews with emergency department (ED) clinical staff working during the two-day event was undertaken in 2016.

Findings

Important structural elements of the in-event health care facility included: physical spaces, such as the clinical zones in the marathon health tent and surrounding area, and access and egress points; and resources such as bilingual staff, senior medical staff, and equipment such as electrocardiograms (ECGs) and intravenous fluids. Process elements of the in-event health care facility included clear communication pathways, as well as inter-professional care coordination and engagement involving shared knowledge of and access to resources, and distinct but overlapping clinical scope between nurses and doctors. This was seen to be critical for timely care provision and appropriate case management. Staff reported many perceived benefits and opportunities of in-event health care delivery, including ED avoidance and disaster training.

Conclusions

This in-event model of emergency care delivery, established in an out-of-hospital location, enabled the delivery of acute health care that could be clearly described and defined. Staff reported satisfaction with their ability to provide a meaningful contribution to hospital avoidance and to the local community. With the number of sporting mass gatherings increasing, this temporary, in-event model of health care provision is one option for event and health care planners to consider.

JohnstonANB, WadhamJ, Polong-BrownJ, AitkenM, RanseJ, HuttonA, RichardsB, CrillyJ.Health care provision during a sporting mass gathering: a structure and process description of on-site care delivery. Prehosp Disaster Med. 2019;34(1):62–71.
Insight: life, death, and ephemerality of Postmodern Architecture
Authors: Szacka Léa-Catherine
Published: January 2019

In De Arquitectura, Vitruvius lists three interrelated Latin terms – firmitas (strength or structural stability), utilitas (functionality or appropriate spatial accommodation), and venustas (beauty or attractive appearance), as being the basis of good architecture. Regarding firmitas, he implies that a good architect needs to choose the best and most solid materials, regardless of their cost. Yet, perhaps dismissing Vitruvius's advice, in the late 1970s and early 1980s, most Postmodern architects went on to erect buildings that often looked more like stage sets than anything strong and durable.

Postmodern designers applied colour, pattern, and ornament to buildings, transferring ordinary and everyday popular imagery, forms, and material into high culture. By rejecting modern design and aesthetics, they also dismissed the building techniques and materials used by their predecessors. As explained by experts from the Portland-based architecture firm Peter Meijer Architect, PC (PMA), ‘there is an inherent impermanence of the original materials based on a default decision making process that limited a building's longevity to a twenty-five year life-cycle’ for Postmodern architecture. In other words, Postmodern buildings were often built as ephemeral constructions, for which longevity was not an absolute value.
Relationships between stress, demographics and dietary intake behaviours among low-income pregnant women with overweight or obesity
Authors: Chang Mei-Wei , Tan Alai , Schaffir Jonathan
Published: January 2019

Objective

To identify demographic risk factors associated with high stress and examine the relationships between levels of stress, demographics and dietary fat, fruit and vegetable intakes in low-income pregnant women with overweight or obesity.

Design

A cross-sectional study.

Setting

Participants were recruited from the Special Supplemental Nutrition Program for Women, Infants, and Children in Michigan, USA.

Participants

Participants (n 353) were non-Hispanic Black (black) or White (white).

Results

Women aged 35 years or older (OR=4·09; 95% CI 1·45, 11·51) and who had high school or less education (OR=1·88; 95% CI 1·22, 2·89) or were unemployed (OR=1·89; 95% CI 1·15, 3·12) were significantly more likely to report high stress than women who were younger, had at least some college education or were employed/homemakers. However, race and smoking status were not associated with level of stress. Women with high stress reported significantly lower fruit and vegetable intakes but not fat intake than women with low stress. Women aged 35 years or older reported significantly higher vegetable but not fat or fruit intake than women who were 18–24 years old. Black women reported significantly higher fat but not fruit or vegetable intake than white women. Education, employment and smoking status were not significantly associated with dietary intake of fat, fruits and vegetables.

Conclusions

Nutrition counselling on reducing fat and increasing fruit and vegetable intakes may consider targeting women who are black or younger or who report high stress, respectively.
Cultural aspects of vaginismus therapy: a case series of Arab-Muslim patients
Authors: Zgueb Yosra , Ouali Uta , Achour Radhouane , Jomli Rabaa , Nacef Fethi
Published: January 2019

Vaginismus in one of the most frequent causes of non-consummation of marriage, and of infertility, in Arab-Muslim societies. Cognitive behavioural therapy (CBT) proved to be effective, but it is important to consider the cultural context of the patient attending CBT for vaginismus. The aim of our study was therefore to draw attention to the belief systems and behaviours linked to female sexuality and couple relationship in the Arab-Muslim culture. We present a series of four patients representative of the local culture and show how treatment strategies were adapted to fit these behaviours and belief systems, as well as environmental factors. We found that excessive closeness of family members, allowing the family to be intrusive and exercising pressure on the couple, a strict education which highly values virginity, transmits fear of ‘the male’ and fear of sex, and which links sex with pain, were the common denominator of all patients of our case series. We adapted the classical CBT strategies for vaginismus to our cultural context. The educational component was enlarged. Cognitive techniques were used to modify specific traditional beliefs. The integration of the family, and not only of the partner, into the treatment process proved uniquely beneficial for the patients.
Perceived Overqualification and Psychological Well-Being Among	Immigrants
Authors: Wassermann Maria , Hoppe Annekatrin
Published: January 2019

Abstract. Migration is often driven by immigrants’ hope of improving their job situation. However, in the host country, they are at risk of holding jobs below their qualifications. This study examines the relationship between perceived overqualification and psychological well-being (depressive symptoms and life satisfaction) among 176 Italian immigrants in Germany along with the buffering role of optimism and meaning-making. The results show that perceived overqualification is associated with higher levels of depressive symptoms and lower levels of life satisfaction. Optimism moderates the relationship between perceived overqualification and life satisfaction: the relationship is attenuated with increasing optimism. We conclude that interventions that enhance optimism could help immigrants cope with perceived overqualification.
Reservoir Operations to Mitigate Drought Effects With a Hedging Policy Triggered by the Drought Prevention Limiting Water Level
Authors: Chang Jianxia , Guo Aijun , Wang Yimin , Ha Yanping , Zhang Ran , Xue Lu , Tu Ziqian
Published: January 2019

Severe drought events worldwide have considerably unfavorable effects on social and economic development. This paper proposes a hedging policy triggered by the seasonal drought prevention limiting water level (DPLWL) for reservoir operations during a drought event. By using this hedging policy, water resources managers can determine operating policies for drought emergence management according to specific drought conditions. A modeling framework that determines the seasonal DPLWL under different drought conditions is developed based on long‐term hydrological and meteorological information and optimal reservoir operation schemes. In particular, Fisher's optimal partitioning algorithm is applied to identifying the seasonality of the DPLWL based on hydroclimatological factors and reservoir storage conditions. The multireservoir system in the Yellow River Basin is used as a case study to assess the performance of the hedging policy triggered by DPLWLs. The results show that DPLWL has a significant advantage over the standard reservoir operation rules when dealing with multireservoir operation for drought mitigation.
Proactive, Reactive, and Inactive Pathways for Scientists in a Changing World
Authors: McDonald Karlie S. , Hobday Alistair J. , Thompson Peter A. , Lenton Andrew , Stephenson Robert L. , Mapstone Bruce D. , Dutra Leo X. C. , Bessey Cindy , Boschetti Fabio , Cvitanovic Christopher , Bulman Catherine M. , Fulton Elizabeth A. , Moeseneder Christian H. , Pethybridge Heidi , Plagányi Eva E. , van Putten E. Ingrid , Rothlisberg Peter C.
Published: January 2019

As atmospheric CO2levels continue to rise so too does the risk of severe impacts. Scientists clearly have an important role to play in preparing for and responding to climate change impacts; however, calls by scientists for global action have not led to the required changes. It is timely, therefore, for scientists to critically consider their own approach toward climate change research, particularly if we are to ameliorate or adapt to unwanted outcomes. Here we present three different pathways that allow scientists and scientific institutions to conceptualize the implications of their responses to climate change scenarios. These pathways are illustrated via three plausible futures for the marine environment under climate change. This approach allows future responsibilities, outcomes, and implication to be explored within and across pathways and can be applied to different scenarios for scientists and scientific institutions to anticipate and better prepare to contribute effectively to the future.
Detection of Transient Denitrification During a High Organic Matter Event in the Black Sea
Authors: Fuchsman Clara A. , Paul Barbara , Staley James T. , Yakushev Evgeniy V. , Murray James W.
Published: January 2019

N2 production by denitrification can occur in anoxic water or potentially inside organic particles. Here we compare data from the Black Sea, a permanently anoxic basin, during two organic matter regimes: suspended particulate organic matter concentrations were high in the oxycline after the spring bloom in March 2005 compared to lower organic matter concentrations in June 2005, May and October 2007, July 2008, and May 2001. For all cruises, N2 gas had a maximum in the suboxic zone (O2 < 10 μmol/L). During the high organic matter event (March 2005), an additional shallower N2 gas and δ15N‐N2 maxima occurred above the suboxic zone in the oxycline where oxygen concentrations were 30–50 μmol/L. Examination of 16S rRNA indicated that anammox bacteria were not present in the oxycline. The δ15N of biologically produced N2 in the oxycline in March 2005 was significantly enriched (+7‰ to +38‰), not depleted, as would be expected from water column fractionation. A simple diffusion calculation indicated that ammonium produced from remineralization inside particles could be oxidized to nitrate and then completely consumed by denitrification inside the particle. In this calculation, half of denitrified N atoms originated from organic N [δ15N = 11‰] and half of N atoms originated from ambient nitrate [δ15N = 5‰–7‰], producing enriched δ15N‐N2 values. We suggest that denitrifiers were active in microzones inside particulates in hypoxic waters above the suboxic zone of the Black Sea. Denitrification in particles may also explain previous data from the oxycline above ocean oxygen deficient zones.
Evidence for Rupture Through a Double Benioff Zone During the 2017Mw8.2 Chiapas, Mexico Earthquake
Authors: Zhang Hao , Brudzinski Michael R.
Published: January 2019

We combine multi‐array relative back‐projection of high‐frequencyPwaves and finite‐fault modeling of low‐frequencyPwaves from the 8 September 2017Mw8.2 Chiapas, Mexico earthquake to image unilateral rupture on a southeast‐northwest striking subvertical fault plane over depths of 10–70 km. Improved multi‐array relative back‐projection estimates of rupture speed and fault geometry provide key refinements to the slip model from finite‐fault modeling. Compilation of prior seismicity and aftershocks reveals the earthquake initiated in the lower plane of a double Benioff zone (DBZ) and ruptured with large slip across the entire DBZ. The previously aseismic interior does not appear to be due to lack of stress as both planes show downdip extension stresses. Instead, tomographic imaging of DBZs find high Poisson's ratio with fast velocities in the DBZ interior, so we propose that highly hydrated harzburgite generates velocity‐strengthening behavior that inhibits earthquake nucleation, yet it can slip seismically during dynamic weakening from a large throughgoing rupture.
Relation Between Arctic Moisture Flux and Tropical Temperature Biases in CMIP5 Simulations and Its Fingerprint in RCP8.5 Projections
Authors: Lee Sukyoung , Woods Cian , Caballero Rodrigo
Published: January 2019

Arctic moisture intrusions have played an important role in warming the Arctic over the past few decades. A prior study found that Coupled Model Intercomparison Project Phase 5 (CMIP5) models exhibit large regional biases in the moisture flux across 70°N. It is shown here that the systematic misrepresentation of the moisture flux is related to the models' overprediction of zonal wavenumber k = 2 contribution and underprediction of k = 1 contribution to the flux. Models with a warmer tropical upper troposphere and El‐Niño‐like tropical surface temperature tend to simulate stronger k = 2 flux, while k = 1 flux is uncorrelated with tropical upper tropospheric temperature and is associated with La‐Niña‐like surface temperature. The models also overpredict the transient eddy moisture flux while underpredicting the stationary eddy flux. Moreover, future projections in Representative Concentration Pathway 8.5 (RCP8.5) simulations show trends in moisture flux that is consistent with biases in historical simulations, suggesting that these CMIP5 projections reflect the same error(s) that cause the model biases.
Development of Side Bidirectional Leader and Its Effect on Channel Branching of the Progressing Positive Leader of Lightning
Authors: Yuan Shanfeng , Jiang Rubin , Qie Xiushu , Sun Zhuling , Wang Dongfang , Srivastava Abhay
Published: January 2019

Fine time‐resolved images of the development of lightning bidirectional leaders below the cloud base were captured by a high‐speed camera in association with multiband electromagnetic field measurements. The bileaders tended to originate at a radial distance of about 200 m from a progressing positive leader channel, propagating more or less radially toward and away from the main channel. Significant asymmetrical channel extensions at opposite ends were clearly recognized. The positive ends of the bileaders propagated in single paths with average speed of 6.1 × 104 m/s, while the opposite negative end involved obvious branching and stepping propagation with average speed of 1.6 × 105 m/s. The bidirectional leaders eventually connected to the existing main positive leader, producing new branches of the flash. Another cause of positive leader branching was that the positive leader split at its head and developed into different branches synchronously, which were sometimes invisible but were revealed by recoil leaders.
How Does the Seasonal Cycle Control Equatorial Atlantic Interannual Variability?
Authors: Prodhomme C. , Voldoire A. , Exarchou E. , Deppenmeier A.‐L. , García‐Serrano J. , Guemas V.
Published: January 2019

It has long been thought that reducing mean‐state biases would lead to improvements in variability. However, so far, there is no confirmation of a relation between model mean biases and variability. While most coupled models exhibit substantial sea surface temperature (SST) biases in the Tropical Atlantic, they are still able to reproduce reasonable SST variability in the basin. We investigate the relationship between the first‐ and second‐order moments of the SST distribution in the equatorial Atlantic using Coupled Model Intercomparison Project Phase 5 simulations. Results suggest that the ability of the coupled models to properly reproduce the interannual variability is linked to their ability to simulate a realistic seasonal cycle evolution, that is, a realistic cold tongue development and a realistic Bjerknes feedback during the beginning of summer, rather than to their ability to represent the summer SST climatology.
Statistical Properties of Sub‐Ion Magnetic Holes in the Dipolarized Magnetotail: Formation, Structure, and Dynamics
Authors: Shustov P. I. , Zhang X.‐J. , Pritchett P. L. , Artemyev A. V. , Angelopoulos V. , Yushkov E. V. , Petrukovich A. A.
Published: January 2019

Magnetic energy release during magnetic reconnection in the magnetotail leads to fast plasma flows transporting thermal energy toward the inner magnetosphere or deep tail. The interaction of such flows with the ambient plasmas is controlled by forces at the flow's leading edge, manifested as a sharp enhancement of the south‐north component of magnetic field there, which has been called the dipolarization front. In this study, we examine the kinetic plasma structure of equatorial magnetic field perturbations observed behind dipolarization fronts. Using statistical observations of dipolarization fronts in the near‐Earth magnetotail by Time History of Events and Macroscale Interactions during Substorms mission, we find sub‐ion scale (scale is below ion gyroradius) magnetic field depressions (magnetic holes), mostly around the equatorial plane, drifting dawnward. They are populated by hot, transversely anisotropic electrons, likely heated around the front. Combining spacecraft observations, analytical estimates, and particle‐in‐cell simulations, we suggest that these holes result from the ballooning/interchange instability at the dipolarization front. They may represent the nonlinear stage of magnetic field perturbations associated with front instability, which trap hot electrons behind the front. We also discuss the possible role of these holes in scattering and heating electrons and ions in the dipolarized magnetotail.
Variability of Intra–D Ring Azimuthal Magnetic Field Profiles Observed on Cassini's Proximal Periapsis Passes
Authors: Provan G. , Cowley S. W. H. , Bunce E. J. , Bradley T. J. , Hunt G. J. , Cao H. , Dougherty M. K.
Published: January 2019

We overview the properties of the azimuthal magnetic fields observed during the periapsis passes of the final 23 orbits of the Cassini spacecraft, including the partial orbit at end of mission, on near equatorial field lines passing inside of Saturn's D ring. The signatures are variable in form and amplitude, though generally approximately symmetric about the point where the spacecraft trajectory lies tangent to a flux shell, corresponding to where the ionospheric field line feet map closest to the equator, consistent with the effect of interhemispheric field‐aligned currents. The perturbations usually begin and end near symmetrically at some point on field lines threading the D ring and extend into the interior region, but in no case do they clearly extend outward onto field lines passing through the C ring. About 35% of cases display a ~20‐40 nT single positive central field peak indicative of southward field‐aligned current flow, while a further ~30% display two or three weaker ~10‐20 nT positive peaks indicative of multiple sheets of northward and southward current. Significant smaller‐scale >5 nT peak‐to‐peak field fluctuations are commonly superposed. A further ~20% of cases exhibit unique profiles within the data set, including two with ~20‐30 nT negative fields and two with only <10 nT fluctuating fields. The variable nature of the signatures is not connected with the pass altitude, local time, planetary period oscillation phase, or D68 ringlet phase but may relate to variable structured thermospheric winds and/or ionospheric conductivities that suggest a significant dynamical role for D ring‐atmosphere interactions.
Paleoearthquakes and Rupture Behavior of the Lenglongling Fault: Implications for Seismic Hazards of the Northeastern Margin of the Tibetan Plateau
Authors: Guo Peng , Han Zhujun , Mao Zebin , Xie Zhangdi , Dong Shaopeng , Gao Fan , Gai Hailong
Published: January 2019

The Lenglongling fault (LLLF) is located along the northeastern margin of the Tibetan Plateau and forms a part of the Tianzhu seismic gap along the Qilian‐Haiyuan fault zone. Little is known about the recurrence of large earthquakes along the LLLF nor the associated seismic hazards of the gap. Here the six most recent surface rupturing paleoearthquakes of the LLLF are revealed by measurement of offset landforms, trench excavations, and radiocarbon dating. They are labeled E1–E6 from youngest to oldest, and their timings are constrained to the following time ranges: 636–498 to present, 2951–1155, 4016–3609, 5325–4476, 7284–6690, and 8483–7989 years BP, respectively. The LLLF displays evidence of fresh, recent surface rupture, and the trench sections reveal that the fault ruptured to the ground surface during the most recent event. Based on this fresh surface rupture and historical earthquake records, the latest event E1 was most likely the 1927 M8.0 Gulang earthquake. In conjunction with previous studies, Gulang earthquake might be a complicated event characterized by the combined rupture of both strike‐slip and thrust faults. The average recurrence interval of the six paleoearthquakes is 1643 ± 568 years, and the coefficient of variation is 0.34, indicating that the LLLF follows a quasiperiodic recurrence model. Based on this new understanding of the last event, the LLLF may not be a part of the Tianzhu seismic gap. However, an earthquake of up to MW7.6 could still rupture the gap sections composed of the Jinqianghe, Maomaoshan, and Laohushan faults.
Early Inception of the Laramide Orogeny in Southwestern Montana and Northern Wyoming: Implications for Models of Flat‐Slab Subduction
Authors: Carrapa B. , DeCelles P. G. , Romero M.
Published: January 2019

Timing and distribution of magmatism, deformation, exhumation, and basin development have been used to reconstruct the history of Laramide flat‐slab subduction under North America during Late Cretaceous‐early Cenozoic time. Existing geodynamic models, however, ignore a large (~40,000‐km2) sector of the Laramide foreland in southwestern Montana. The Montana Laramide ranges consist of Archean basement arches (fault‐propagation folds) that were elevated by thrust and reverse faults. We present new thermochronological and geochronological data from six Laramide ranges in southwestern Montana (the Beartooth, Gravelly, Ruby and Madison Ranges, and the Tobacco Root and Highland Mountains) that show significant cooling and exhumation during the Early to mid‐Cretaceous, much earlier than the record of Laramide exhumation in Wyoming. These data suggest that Laramide‐style deformation‐driven exhumation slightly predates the eastward sweep of magmatism in western Montana, consistent with geodynamic models involving initial strain propagation into North American cratonic rocks due to stresses associated with a northeastward expanding region of flat‐slab subduction. Our results also indicate various degrees of Cenozoic heating and cooling possibly associated with westward rollback of the subducting Farallon slab, followed by Basin‐and‐Range extension.
Transverse Momentum Exchange Induced by Large Coherent Structures in a Vegetated Compound Channel
Authors: Truong S. H. , Uijttewaal W. S. J.
Published: January 2019

In floodplains of vegetated channels, transverse exchange processes of mass and momentum are of primary importance as these are directly linked to the river bank stability, sedimentation, and nutrient transport. Despite its importance, knowledge about this phenomenon is still incomplete especially in the context of the presence of the large horizontal coherent structures (LHCSs). As a result, although various exchange models have been developed, their applicability in different circumstances is still unclear as their validity is usually restricted to a narrowly ranging experiment data set. A proper model for this exchange in a compound channel geometry with or without vegetation is lacking. In order to obtain more insight, a laboratory experiment of a shallow flow field in a compound vegetated channel has been conducted. A quadrant analysis of the Reynolds shear stresses has been applied to study the connection between the cycloid flow events induced by the LHCSs and transverse momentum exchange in the channel. It is suggested that local variability leads to differences in the transverse exchange of momentum. Furthermore, the experimental data were used to verify state‐of‐the‐art momentum exchange models. As the limitations of those models were analyzed, for the first time a hybrid eddy viscosity model based on the occurrence of LHCSs and the presence of vegetation was proposed and validated using a variety of experimental data sets. The results suggest that the transverse momentum exchange can be well modeled with the new eddy viscosity model for quite a range of different setups and scenarios by varying only a coefficient of proportionality β, which is related to the transverse slope between the main channel and the floodplain.