bluuebunny/crossref_metadata_2025 huggingface dataset:
Bronchodilator responsiveness in children with asthma is not influenced by spacer device selection
Authors: D'Vaz Nina , Okitika Toluwalose A. , Shackleton Claire , Devadason Sunalene G. , Hall Graham L.
Published: February 2019

Introduction

Spacer devices optimize delivery of aerosol therapies and maximize therapeutic efficacy. We assessed the impact of spacer device on the prevalence and magnitude of bronchodilator response (BDR) in children with asthma.

Methods

Children with physician confirmed asthma and parentally reported symptoms in the last 12 months were recruited for this study. Each participant completed two separate visits (5‐10 days apart) with spirometry performed at baseline and following cumulative doses of salbutamol (200, 400, 800, and 200 μg) delivered by either a small volume disposable spacer or a large volume multi‐use spacer. Spacer type was alternated for each participant during each visit. The primary outcome was the effect of spacer type on bronchodilator responsiveness. The secondary outcome was to assess the relationships between spacer device, salbutamol dose and the proportion of children with a clinically relevant BDR.

Results

Thirty‐two children (mean age 11.8 years) completed both visits. Change in lung function following bronchodilators was increased using the large volume spacer, for relative but not absolute increase in FEV1 [mean difference (95% confidence intervals): 1.28% (0.02, 2.54; P = 0.047) and 0.013 L (−0.01, 0.04; P = 0.288)], respectively. There was no observed difference in FVC by spacer type. Overall, 59% (n = 19) of children exhibited a clinically relevant BDR at 400 µg of salbutamol for any spacer and was independent of spacer type.

Conclusion

Spacer device was not associated with clinically important differences in lung function following bronchodilator inhalation in children with asthma. At a recommended dose of 400 μg, some children with asthma may have their bronchodilator responsiveness misclassified.
Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry analysis for characterization of lignin oligomers using cationization techniques and 2,5‐dihydroxyacetophenone (DHAP) matrix
Authors: Bowman Amber S. , Asare Shardrack O. , Lynn Bert C.
Published: February 2019

Rationale

Effective analytical techniques are needed to characterize lignin products for the generation of renewable carbon sources. Application of matrix‐assisted laser desorption/ionization (MALDI) in lignin analysis is limited because of poor ionization efficiency. In this study, we explored the potential of cationization along with a 2,5‐dihydroxyacetophenone (DHAP) matrix to characterize model lignin oligomers.

Methods

Synthesized lignin oligomers were analyzed using the developed MALDI method. Two matrix systems, DHAP and α‐cyano‐4‐hydroxycinnamic acid (CHCA), and three cations (lithium, sodium, silver) were evaluated using a Bruker UltraFlextreme time‐of‐flight mass spectrometer. Instrumental parameters, cation concentration, matrix, sample concentrations, and sample spotting protocols were optimized for improved results.

Results

The DHAP/Li+ combination was effective for dimer analysis as lithium adducts. Spectra from DHP and ferric chloride oligomers showed improved signal intensities up to decamers (m/z 1823 for the FeCl3 system) and provided insights into differences in the oligomerization mechanism. Spectra from a mixed DHP oligomer system containing H, G, and S units showed contributions from all monolignols within an oligomer level (e.g. tetramer level).

Conclusions

The DHAP/Li+ method presented in this work shows promise to be an effective analytical tool for lignin analysis by MALDI and may provide a tool to assess lignin break‐down efforts facilitating renewable products from lignin.
Preoperative identification of the initial burr hole site in retrosigmoid craniotomies: A teaching and technical note
Authors: Zhou Chuan , Evins Alexander I. , Boschi Andrea , Tang Yinda , Li Shiting , Przepiorka Lukasz , Sadhwani Shaan , Stieg Philip E. , Xu Tao , Bernardo Antonio
Published: February 2019

Background

When fashioning a retrosigmoid craniotomy, precise placement of the initial burr hole is crucial to avoid iatrogenic sinusal injury and to facilitate a corridor that allows for minimal cerebellar retraction.

Methods

3D CT reconstructions of 16 cadaveric sides were used to identify and measure three discrete anatomical points. These three points and distances between them were plotted onto the surface of the skull using a digital caliper to identify the optimal burr hole location. This technique was subsequently applied in 20 clinical cases.

Results

Optimal burr hole placement was achieved in 87.5% of specimens and, with minor refinement, 100% of clinical cases with no significant increase in operative time. Preoperative planning took an average of 10 minutes.

Conclusion

This technique for localizing the location of the initial retrosigmoid burr hole is a simple, safe, reliable, rapid, and inexpensive solution for surgeons who do not have regular access to neuronavigation.
A model‐based bone milling state identification method via force sensing for a robotic surgical system
Authors: Al‐Abdullah Kais I. , Lim Chee Peng , Najdovski Zoran , Yassin Wisam
Published: February 2019

Background

This paper presents a model‐based bone milling state identification method that provides intraoperative bone quality information during robotic bone milling. The method helps surgeons identify bone layer transitions during bone milling.

Methods

On the basis of a series of bone milling experiments with commercial artificial bones, an artificial neural network force model is developed to estimate the milling force of different bone densities as a function of the milling feed rate and spindle speed. The model estimations are used to identify the bone density at the cutting zone by comparing the actual milling force with the estimated one.

Results

The verification experiments indicate the ability of the proposed method to distinguish between one cortical and two cancellous bone densities.

Conclusions

The significance of the proposed method is that it can be used to discriminate a set of different bone density layers for a range of the milling feed rate and spindle speed.
Concise Review: Canine Diabetes Mellitus as a Translational Model for Innovative Regenerative Medicine Approaches
Authors: Moshref Maryam , Tangey Bonnie , Gilor Chen , Papas Klearchos K. , Williamson Peter , Loomba-Albrecht Lindsey , Sheehy Paul , Kol Amir
Published: February 2019

Diabetes mellitus (DM) is a common spontaneous endocrine disorder in dogs, which is defined by persistent hyperglycemia and insulin deficiency. Like type 1 diabetes (T1D) in people, canine DM is a complex and multifactorial disease in which genomic and epigenomic factors interact with environmental cues to induce pancreatic β-cell loss and insulin deficiency, although the pathogenesis of canine DM is poorly defined and the role of autoimmunity is further controversial. Both diseases are incurable and require life-long exogenous insulin therapy to maintain glucose homeostasis. Human pancreatic islet physiology, size, and cellular composition is further mirrored by canine islets. Although pancreatic or isolated islets transplantation are the only clinically validated methods to achieve long-term normoglycemia and insulin independence, their availability does not meet the clinical need; they target a small portion of patients and have significant potential adverse effects. Therefore, providing a new source for β-cell replacement is an unmet need. Naturally occurring DM in pet dogs, as a translational platform, is an untapped resource for various regenerative medicine applications that may offer some unique advantages given dogs’ large size, longevity, heterogenic genetic background, similarity to human physiology and pathology, and long-term clinical management. In this review, we outline different strategies for curative approaches, animal models used, and consider the value of canine DM as a translational animal/disease model for T1D in people. Stem Cells Translational Medicine  2019;8:450–455
Microwave‐Assisted One‐Pot [3+2] Cycloaddition of Azomethine Ylides and 3‐Alkenyl Oxindoles: A Facile Approach to Pyrrolidine‐Fused Bis‐Spirooxindoles
Authors: Bhandari Sonal , Sana Sravani , Sridhar Balasubramanyam , Shankaraiah Nagula
Published: February 2019

An efficient microwave‐assisted one‐pot method has been developed for the construction of pyrrolidine fused bis‐spirooxindoles through insitu generated azomethine ylide from decarboxylative condensation of isatins and primary α‐amino acids with concomitant [3+2] cycloaddition of 3‐alkenyl oxindoles. These reactions were effectively accelerated by microwave irradiation in ethanol solvent without any additives or catalyst and enable broad substrate scope, atom‐economy, eco‐friendly, and good yields. The structure and stereochemistry of pyrrolidine fused bis‐spirooxindole ring was unambiguously established by single‐crystal X‐ray analysis.
Impact of Welan Gum on Cement Paste Containing PCE Superplasticizers with Different Charge Densities
Authors: Wang Fang , Wang Dongmin , Wang Qibao , Yu Jie , Shi Jiajia
Published: February 2019

As a renewable materials, welan gum is microbial biopolymer which is fermented by bacteria. It is widely used in self‐compacting concrete because of its excellent rheological properties. After adding welan gum, the fluidity of cement will decrease rapidly. So it needs to be used together with superplasticizer. Two polycarboxylate superplasticizer with the acid/ether radio of 2 (PC‐2)and with the acid/ether radio of 6 (PC‐6)were synthesized. By FTIR measurements, carboxyl functional groups exists in the dialysed polymer. The specific anionic charge density measurement shows that PC‐6 provide more COO− than PC‐2 in alkaline solution. And TOC test analysis shows that the adsorbed amount of PC‐6 is higher than PC‐2 with low anionic charge density. PC‐6 with the higher COO− seems to be more affected by welan gum than PC‐2. From the rheological properties of cement paste mixed with PCEs and welan gum, it can be concluded that the addition of welan gum aggravates the trend of shear thickening. Hydration heat flow at different temperatures indicates the selected welan gum is capable of retarding early cement hydration even in high temperatures. Finally, the film forming property of the welan gum was initially studied through water loss rate test, and the film formation mechanism needs to be studied in the future.
A Novel One‐Pot Three‐Component Reaction for Rapid Access of Arylidene 2‐Aminoimidazolone Derivatives
Authors: Hanif Aansa , Sardar Aniqa , Alazmi Meshari , Tariq Haniya , Emwas Abdul‐Hamid , Gao Xin , Chotana Ghayoor Abbas , Zaib Saleem Rahman Shah
Published: February 2019

A simple and convenient one‐pot reaction for the synthesis of arylidene 2‐aminoimidazolone derivatives from structurally diverse benzaldehydes, amines and 2‐(methylthio)‐1H‐imidazol‐4(5H)‐one is described. The reaction offers flexibility of use of electron‐rich and electron‐deficient benzaldehydes and mono and di‐substituted amines for the rapid development of combinatorial library.
Rapid, Simple and Efficient Microwave‐Assisted Alkylation of 6‐Acetyl‐2H‐Benzo[e][1, 3] Oxazine‐2, 4(3H)‐Dione
Authors: Gojiya Dinesh G. , Vekariya Mitesh B. , Kapupara Vimal H. , Bhatt Tejal D. , Kalavadiya Prakash L. , Joshi Hitendra S.
Published: February 2019

A simple, efficient and eco‐friendly method has been developed for the synthesis of biologically active alkyl derivatives of 6‐acetyl‐2H‐benzo[e][1,3]oxazine‐2,4(3H)‐dione by using microwave irradiations. The N‐alkylation of 6‐acetyl‐2H‐benzo[e][1,3]oxazine‐2,4(3H)‐dione with substituted alkyl derivatives under microwave radiations in presence of Tetra‐n‐butyl ammonium bromide as a phase transfer catalyst to give the desired products. Comparison between conventional and microwave‐assisted synthesis revealed that it reduced the reaction time, improve the yield and purity of 6‐acetyl‐3‐(substituted alkyl)‐2H‐benzo[e][1,3]oxazine‐2,4(3H)‐diones analog molecules. All the final compounds were characterized by FT‐IR, 1HNMR, 13CNMR, HRMS and Mass spectroscopic analysis, also succeeded to develop and analyze the single crystal XRD of compound 4 f. The antimicrobial evaluation studies show moderate activities against used microbes.
Value creation and value appropriation in public and nonprofit organizations
Authors: Cabral Sandro , Mahoney Joseph T. , McGahan Anita M. , Potoski Matthew
Published: February 2019

Research Summary

In recent years, strategy scholarship expanded its scope beyond the realm of private firms. Despite notable advances, the field still lacks theoretical and empirical frameworks for fully understanding how public and nonprofit organizations interact with private firms to create and appropriate value. By recognizing the inherent complexity of interactions between organizations with different purposes and the existing challenges for designing effective governance arrangements, we assess how recent scholarship addresses some dilemmas related to both private and public value creation. Based on the extant literature and on some novel aspects raised by the articles in this issue, we also propose a framework to advance strategy research in the field. We emphasize the importance of stakeholder management capabilities among public, private, and nonprofit organizations in pursuit of enhanced public value and continuous support from appreciative stakeholders.

Managerial Summary

Despite abundant examples of governance arrangements involving public, private, and nonprofit organizations (e.g., public‐private partnerships and alliances involving NGOs, firms, multilateral organizations, public contracting, and so on), the strategic management field has only recently given attention to value creation and value appropriation beyond the scope of private organizations. Here we connect strategic management and public management to identify relevant dimensions that shape value‐creating strategies and underpinning outcomes in public‐private‐nonprofit interactions. We highlight that public value arises from private interests and that the dynamic of value creation and value appropriation in activities involving the public interest can be influenced by not only resource endowments and organizational capabilities but also by the way organizations address and manage stakeholder expectations.
Translucent Photodetector with Blended Nanowires–Metal Oxide Transparent Selective Electrode Utilizing Photovoltaic and Pyro‐Phototronic Coupling Effect
Authors: Abbas Sohail , Kumar Mohit , Kim Dong‐Wook , Kim Joondong
Published: February 2019

ZnO is a potential candidate for photodetection utilizing the pyroelectric effect. Here, a self‐biased and translucent photodetector with the configuration of Cu4O3/ZnO/FTO/Glass is designed and fabricated. In addition, the pyroelectric effect is effectively harvested using indium tin oxide (ITO), silver nanowires (AgNWs), and a blend of AgNWs‐coated ITO as the transparent selective contact electrode. The improved rise times are observed from 1400 µs (bare condition; without the selective electrode) to 69, 60, 7 µs, and fall times from 720 µs (bare condition) to 80, 70, 10 µs for corresponding ITO, AgNWs, and AgNWs‐coated ITO contact electrodes, respectively. Similarly, the responsivity and detectivity are enhanced by about 4.39 × 107 and 5.27 × 105%, respectively. An energy band diagram is proposed to explain the underlying working mechanism based on the workfunction of the ITO (4.7 eV) and AgNWs (4.57 eV) as measured by Kelvin probe force microscopy, which confirms the formation of type‐II band alignment resulting in the efficient transport of photogenerated charge carriers. The functional use of the transparent selective contact electrode can effectively harness the pyro‐phototronic effect for next‐generation transparent and flexible optoelectronic applications.
Few‐Layered Tin Sulfide Nanosheets Supported on Reduced Graphene Oxide as a High‐Performance Anode for Potassium‐Ion Batteries
Authors: Fang Lingzhe , Xu Jing , Sun Shuo , Lin Baowei , Guo Qiubo , Luo Da , Xia Hui
Published: February 2019

Anodes involving conversion and alloying reaction mechanisms are attractive for potassium‐ion batteries (PIBs) due to their high theoretical capacities. However, serious volume change and metal aggregation upon potassiation/depotassiation usually cause poor electrochemical performance. Herein, few‐layered SnS2 nanosheets supported on reduced graphene oxide (SnS2@rGO) are fabricated and investigated as anode material for PIBs, showing high specific capacity (448 mAh g−1 at 0.05 A g−1), high rate capability (247 mAh g−1 at 1 A g−1), and improved cycle performance (73% capacity retention after 300 cycles). In this composite electrode, SnS2 nanosheets undergo sequential conversion (SnS2 to Sn) and alloying (Sn to K4Sn23, KSn) reactions during potassiation/depotassiation, giving rise to a high specific capacity. Meanwhile, the hybrid ultrathin nanosheets enable fast K storage kinetics and excellent structure integrity because of fast electron/ionic transportation, surface capacitive‐dominated charge storage mechanism, and effective accommodation for volume variation. This work demonstrates that K storage performance of alloy and conversion‐based anodes can be remarkably promoted by subtle structure engineering.
The Effect of Materials Architecture in TiO2/MOF Composites on CO2 Photoreduction and Charge Transfer
Authors: Crake Angus , Christoforidis Konstantinos C. , Gregg Aoife , Moss Benjamin , Kafizas Andreas , Petit Camille
Published: February 2019

CO2 photoreduction to C1/C1+ energized molecules is a key reaction of solar fuel technologies. Building heterojunctions can enhance photocatalysts performance, by facilitating charge transfer between two heterojunction phases. The material parameters that control this charge transfer remain unclear. Here, it is hypothesized that governing factors for CO2 photoreduction in gas phase are: i) a large porosity to accumulate CO2 molecules close to catalytic sites and ii) a high number of “points of contact” between the heterojunction components to enhance charge transfer. The former requirement can be met by using porous materials; the latter requirement by controlling the morphology of the heterojunction components. Hence, composites of titanium oxide or titanate and metal–organic framework (MOF), a highly porous material, are built. TiO2 or titanate nanofibers are synthesized and MOF particles are grown on the fibers. All composites produce CO under UV–vis light, using H2 as reducing agent. They are more active than their component materials, e.g., ≈9 times more active than titanate. The controlled composites morphology is confirmed and transient absorption spectroscopy highlights charge transfer between the composite components. It is demonstrated that electrons transfer from TiO2 into the MOF, and holes from the MOF into TiO2, as the MOF induces band bending in TiO2.
Cultural Baggage: Do Immigrants Import Corruption?
Authors: Bologna Pavlik Jamie , Lujan Padilla Estefania , Powell Benjamin
Published: February 2019

Do immigrants undermine culture in a way that destroys productivity in destination countries? Some scholars have argued that because immigrants come from countries with dysfunctional social capital—norms and institutions—they will import it and pollute the social capital in destination countries. One potential channel through which this could occur is corruption. We examine stocks and flows of immigrants over a 20‐year time period to see if corruption increased in destination countries. We generally find that immigration is not associated with increases in corruption. Additionally, we find that immigration tends to decrease corruption in destination countries with low levels of corruption or high levels of economic freedom.
A new craniid brachiopod genus from the terminal Ordovician Hirnantia fauna of Myanmar and South China
Authors: Chen Di , Rong Jiayu
Published: February 2019

Hirnantian costate craniides are rare in the world; many have only been defined using open taxonomic nomenclature and assigned to the genera Acanthocrania and Philhedra. New material from South China and Myanmar allows establishment of a new genus, Xenocrania, including its type species Palaeocyclus? haimei Reed from the Hirnantia fauna in northern Shan State, Myanmar. This genus is characterized by a unique ornamentation with a large degree of intraspecific variation in sympatric and allopatric populations. Three types of ornamentation (A, B and C) are recognized within the same population of this species, and even on the same individual. Based on this high degree of variation, we consider Xenocrania haimei and Acanthocrania yichangensis Zeng from the Hirnantia fauna of Yichang, western Hubei, South China to be conspecific. X. haimei was probably an opportunistic species, exhibiting considerable significant phenotypic pleiotropy (exemplified by a highly variable ornament) in response to severe ecological stress, particularly during the end Ordovician crisis, enabling the species to survive the extinction event. Geographically, Xenocrania gen. nov. occurs not only in the Hirnantia fauna of Myanmar (Sibumasu) and South China, but also in England (Avalonia), Poland (Baltica) and probably also Bohemia (Perunica). A further reassessment of many nominal or indeterminate taxa of Ordovician and Silurian craniides tentatively attributed to Philhedra, Acanthocrania and other related genera is needed.
Lack of experience‐dependent intrinsic plasticity in the adolescent infralimbic medial prefrontal cortex
Authors: Koppensteiner Peter , Galvin Christopher , Ninan Ipe
Published: February 2019

Fear extinction, an inhibitory learning that suppresses a previously learned fear memory, is diminished during adolescence. Earlier studies have shown that this suppressed fear extinction during adolescence involves an altered glutamatergic plasticity in infralimbic medial prefrontal cortical (IL‐mPFC) pyramidal neurons. However, it is unclear whether the excitability of IL‐mPFC pyramidal neurons plays a role in this development‐dependent suppression of fear extinction. Therefore, we examined whether fear conditioning and extinction affect the active and passive membrane properties of IL‐mPFC layer 5 pyramidal neurons in preadolescent, adolescent and adult mice. Both preadolescent and adult mice exhibited a bidirectional modulation of the excitability of IL‐mPFC layer 5 pyramidal neurons following fear conditioning and extinction, i.e., fear conditioning reduced membrane excitability, whereas fear extinction reversed this effect. However, the fear conditioning‐induced suppression of excitability was not reversed in adolescent mice following fear extinction training. Neither fear conditioning nor extinction affected GABAergic transmission in IL‐mPFC layer 5 pyramidal neurons, suggesting that GABAergic transmission did not play a role in experience‐dependent modulation of neuronal excitability. Our results suggest that the extinction‐specific modulation of excitability is impaired during adolescence.
Management of monoamniotic twins: the question is not ‘where?’, but ‘how?’
Authors: Mieghem T. Van , Shub A.
Published: February 2019

Linked Comment: Ultrasound Obstet Gynecol 2019; 53: 175–183
The End of Epicurean Infinity: Critical Reflections on the Epicurean Infinite Universe
Authors: Bakker Frederik A.
Published: February 2019

In contrast to other ancient philosophers, Epicurus and his followers famously maintained the infinity of matter, and consequently of worlds. This was inferred from the infinity of space, because they believed that a limited amount of matter would inevitably be scattered through infinite space, and hence be unable to meet and form stable compounds. By contrast, the Stoics claimed that there was only a finite amount of matter in infinite space, which stayed together because of a general centripetal tendency. The Roman Epicurean poet Lucretius tried to defend the Epicurean conception of infinity against this Stoic alternative view, but not very convincingly. One might suspect, therefore, that the Epicureans’ adherence to the infinity of matter was not so much dictated by physical arguments as it was motivated by other, mostly theological and ethical, concerns. More specifically, the infinity of atoms and worlds was used as a premise in several arguments against divine intervention in the universe. The infinity of worlds was claimed to rule out divine intervention directly, while the infinity of atoms lent plausibility to the chance formation of worlds. Moreover, the infinity of atoms and worlds was used to ensure the truth of multiple explanations, which was presented by Epicurus as the only way to ward off divine intervention in the realm of celestial phenomena. However, it will be argued that in all of these arguments the infinity of matter is either unnecessary or insufficient for reaching the desired conclusion.
Implementing an interprofessional narrative medicine program in academic clinics: Feasibility and program evaluation
Authors: Gowda Deepthiman , Curran Tayla , Khedagi Apurva , Mangold Michael , Jiwani Faiz , Desai Urmi , Charon Rita , Balmer Dorene
Published: February 2019

Interprofessional education (IPE) is a critical component of medical education and is affected by the characteristics of the clinical teams in which students and residents train. However, clinical teams are often shaped by professional silos and hierarchies which may hinder interprofessional collaborative practice (IPCP). Narrative medicine, a branch of health humanities that focuses on close reading, reflective writing, and sharing in groups, could be an innovative approach for improving IPE and IPCP. In this report, we describe the structure, feasibility, and a process-oriented program evaluation of a narrative medicine program implemented in interprofessional team meetings in three academic primary care clinics. Program evaluation revealed that a year-long narrative medicine program with modest monthly exposure was feasible in academic clinical settings. Staff members expressed engagement and acceptability as well as support for ongoing implementation. Program success required administrative buy-in and sustainability may require staff training in narrative medicine.
High-Index-Faceted Ni3S2 Branch Arrays as Bifunctional Electrocatalysts for Efficient Water Splitting
Authors: Deng Shengjue , Zhang Kaili , Xie Dong , Zhang Yan , Zhang Yongqi , Wang Yadong , Wu Jianbo , Wang Xiuli , Fan Hong Jin , Xia Xinhui , Tu Jiangping
Published: February 2019

For efficient electrolysis of water for hydrogen generation or other value-added chemicals, it is highly relevant to develop low-temperature synthesis of low-cost and high-efficiency metal sulfide electrocatalysts on a large scale. Herein, we construct a new core–branch array and binder-free electrode by growing Ni3S2 nanoflake branches on an atomic-layer-deposited (ALD) TiO2 skeleton. Through induced growth on the ALD-TiO2 backbone, cross-linked Ni3S2 nanoflake branches with exposed {$$\bar{2}10$$

2

¯

10

} high-index facets are uniformly anchored to the preformed TiO2 core forming an integrated electrocatalyst. Such a core–branch array structure possesses large active surface area, uniform porous structure, and rich active sites of the exposed {$$\bar{2}10$$

2

¯

10

} high-index facet in the Ni3S2 nanoflake. Accordingly, the TiO2@Ni3S2 core/branch arrays exhibit remarkable electrocatalytic activities in an alkaline medium, with lower overpotentials for both oxygen evolution reaction (220 mV at 10 mA cm−2) and hydrogen evolution reaction (112 mV at 10 mA cm−2), which are better than those of other Ni3S2 counterparts. Stable overall water splitting based on this bifunctional electrolyzer is also demonstrated.
Economic Development and the“Social Rights Hypothesis”: Regulating Labour Standards in China
Authors: ZOU Mimi
Published: February 2019

This paper provides a critical account of the various roles that labour-law regulation has played in China’s transition to a market-oriented economy. The analysis aims to contribute new insights to an ongoing debate on the relationship between economic development and legal rules and institutions in China. Discussions of social and labour rights have been on the periphery of a debate that has focused on property and contract rights (the so-called “Rights Hypothesis”). While numerous scholars have sought to debunk the explanatory power of the “Rights Hypothesis” in the case of China, I put forward an alternative “Social Rights Hypothesis.” My proposed hypothesis seeks to explain how labour-law rules and institutions have co-evolved with the emergence of a labour market in China’s economic development. Specifically, labour law has played not only a market-constituting role, but also market-corrective and market-limiting functions.
The teams of early-career investigators: A qualitative pilot study
Authors: Norman Marie K. , Hamm Megan E. , Mayowski Colleen A. , Schenker Yael , Kapoor Wishwa N.
Published: February 2019

Introduction: Early team experiences can influence the professional trajectories of early-career investigators profoundly, yet they remain underexplored in the team science literature, which has focused primarily on large, multisite teams led by established researchers. To better understand the unique challenges of teams led by early-career investigators, we conducted a qualitative pilot study.

Methods: Interviews were conducted with the principal investigator and members of 5 teams led by KL2 and K12 scholars at the University of Pittsburgh. A code book was developed and thematic analysis was conducted.

Results: Seven distinct themes emerged. Interview subjects reported a high level of trust and strong communication patterns on their teams; however, the data also suggested underlying tensions that have the potential to escalate into larger problems if unaddressed.

Conclusions: This study yields a deeper understanding of teams led by early-career investigators, which can help us provide appropriately targeted training and support.
A matched cohort examination of publication rates among clinical subspecialty fellows enrolled in a translational science training program
Authors: Ehlers Shawna L. , Cornelius Katherine E. , Greenberg-Worisek Alexandra J. , Warner David O. , Weavers Karen M. , Thomson Kelly R. , Hansen Marissa J. , Larson Joseph J. , Enders Felicity T. , Iyer Prasad G.
Published: February 2019

Purpose

This study examined the effectiveness of a formal postdoctoral education program designed to teach skills in clinical and translational science, using scholar publication rates as a measure of research productivity.

Method

Participants included 70 clinical fellows who were admitted to a master’s or certificate training program in clinical and translational science from 1999 to 2015 and 70 matched control peers. The primary outcomes were the number of publications 5 years post-fellowship matriculation and time to publishing 15 peer-reviewed manuscripts post-matriculation.

Results

Clinical and translational science program graduates published significantly more peer-reviewed manuscripts at 5 years post-matriculation (median 8 vs 5, p=0.041) and had a faster time to publication of 15 peer-reviewed manuscripts (matched hazard ratio = 2.91, p=0.002). Additionally, program graduates’ publications yielded a significantly higher average H-index (11 vs. 7, p=0.013).

Conclusion

These findings support the effectiveness of formal training programs in clinical and translational science by increasing academic productivity.
Experimental research on ultrasound-assisted underwater femtosecond laser drilling
Authors: Sun Xiaoyan , Zhou Jianhang , Duan Ji-An , Du Haifeng , Cui Dongmei , Hu Youwang
Published: February 2019

In order to diminish the occurrence of cavitation bubbles during the liquid-assisted laser machining, ultrasound-assisted underwater femtosecond laser drilling on stainless steel is adopted. This method greatly diminishes the optical disturbance of cavitation bubbles. By investigating and analyzing the effect of laser pulse energy and pulse number on the morphology of the holes, it has been found that ultrasound not only has a remarkable function of forming a hole with clean and flat bottom, but also reduces debris redeposition around the processing area. This method improves the machining quality. Besides, it also improves the depth-to-diameter ratio of the hole about 20%.
Improving Pulse Phase Estimation Accuracy with Sampling and Weighted Averaging
Authors: Lin Haoye , Xu Bo
Published: February 2019

The accuracy in an X-ray pulsar-based navigation system depends mainly on the accuracy of the pulse phase estimation. In this paper, a novel method is proposed which combines an epoch folding process and a cross-correlation method with the idea of “averaging multiple measurements”. In this method, pulse phase is estimated multiple times on the sampled subsets of arriving photons' time tags, and a final estimation is obtained as the weighted average of these estimations. Two explanations as to how the proposed method can improve accuracy are provided: a Signal to Noise Ratio (SNR)-based explanation and an “error-difference trade-off” explanation. Numerical simulations show that the accuracy in pulse phase estimation can be improved with the proposed algorithm.
Fragmented Landscape, Fragmented Knowledge: A Synthesis of Renosterveld Ecology and Conservation
Authors: Topp Emmeline N , Loos Jacqueline
Published: February 2019

Knowledge of ecological patterns and processes is key to effective conservation of biodiversity hotspots under threat. Renosterveld is one of the most critically endangered habitats in the biologically unique Cape Floristic Region, South Africa. For the first time, we map and synthesize the current state of knowledge on renosterveld ecology and conservation. We investigated 132 studies for the themes, locations and taxa of renosterveld research and the fragmentation, threats, recommendations and barriers to renosterveld conservation. More studies focused on plants than any other taxa (48% of articles) and are conducted mostly in larger, intact renosterveld fragments. The most commonly identified threat to renosterveld was agricultural intensification; conservation recommendations spanned improved farming practices, formal protection and local patch management. Conservation implementation has been piecemeal and has depended largely on the goodwill of landowners, which can be constrained by costs of conservation measures and a lack of suitable restoration means. Citizen science is a promising potential solution to some barriers. Fragmented knowledge in such a transformed and relatively densely populated region highlights the scale of knowledge gaps for other biodiversity hotspots and has implications for ongoing conservation work.
A Global Assessment of Terrestrial Evapotranspiration Increase Due to Surface Water Area Change
Authors: Zhan Shengan , Song Chunqiao , Wang Jida , Sheng Yongwei , Quan Jiping
Published: February 2019

Surface water, which is changing constantly, is a crucial component in the global water cycle, as it greatly affects the water flux between the land and the atmosphere through evaporation. However, the influences of changing surface water area on the global water budget have largely been neglected. Here we estimate an extra water flux of 30.38 ± 15.51 km3/year omitted in global evaporation calculation caused by a net increase of global surface water area between periods 1984–1999 and 2000–2015. Our estimate is at a similar magnitude to the recent average annual change in global evapotranspiration assuming a stationary surface water area. It is also comparable to the estimated trends in various components of the hydrological cycle such as precipitation, discharge, groundwater depletion, and glacier melting. Our findings suggest that the omission of surface water area changes may cause considerable biases in global evaporation estimation, so an improved understanding of water area dynamics and its atmospheric coupling is crucial to reduce the uncertainty in the estimation of future global water budgets.
A Coherent Statistical Model for Coastal Flood Frequency Analysis Under Nonstationary Sea Level Conditions
Authors: Ghanbari Mahshid , Arabi Mazdak , Obeysekera Jayantha , Sweet William
Published: February 2019

Flood exposure is increasing in coastal communities due to rising sea levels. Understanding the effects of sea level rise (SLR) on frequency and consequences of coastal flooding and subsequent social and economic impacts is of utmost importance for policymakers to implement effective adaptation strategies. Effective strategies may consider impacts from cumulative losses from minor flooding as well as acute losses from major events. In the present study, a statistically coherent Mixture Normal‐Generalized Pareto Distribution model was developed, which reconciles the probabilistic characteristics of the upper tail as well as the bulk of the sea level data. The nonstationary sea level condition was incorporated in the mixture model using Quantile Regression method to characterize variable Generalized Pareto Distribution thresholds as a function of SLR. The performance validity of the mixture model was corroborated for 68 tidal stations along the Contiguous United States (CONUS) coast with long‐term observed data. The method was subsequently employed to assess existing and future coastal minor and major flood frequencies. The results indicate that the frequency of minor and major flooding will increase along all CONUS coastal regions in response to SLR. By the end of the century, under the “Intermediate” SLR scenario, major flooding is anticipated to occur with return period less than a year throughout the coastal CONUS. However, these changes vary geographically and temporally. The mixture model was reconciled with the property exposure curve to characterize how SLR might influence Average Annual Exposure to coastal flooding in 20 major CONUS coastal cities.
A Geodetic Strain Rate and Tectonic Velocity Model for China
Authors: Rui X. , Stamps D. S.
Published: February 2019

The conjoining and interfering influence of the Circum‐Pacific zone and the Tethys‐Himalayan zone make China a country of intense intracontinental seismicity. Here we provide three new quantitatively assessed products and use them to better constrain seismic hazards in China. First, we process ~2,700 Global Positioning System (GPS) data spanning 1996–2017 provided by the Crustal Movement Observation Network of China (CMONOC) network and the Nevada Geodetic Laboratory. To produce a robust tectonic velocity solution, we implement a data editing scheme to account for 8 Mw ≥ 7 earthquakes to reduce the influence of transient phenomena. The solution is then rotated into a consistent reference frame with 10 other published velocity sources surrounding mainland China. Second, we calculate a new geodetic strain rate model using an optimal mesh grid definition of 0.4° × 0.4° determined jointly by the Nyquist frequency method and checkerboard tests. We evaluate and validate the geodetic strain rate results from both a statistical (i.e., based on the Bayesian factor) and quantitative (i.e., based on the comparison with the 2‐D analytical strain rate result) approaches. Third, we use our new geodetic strain rate model to estimate seismicity rates.
Bubble Coalescence and Percolation Threshold in Expanding Rhyolitic Magma
Authors: Giachetti Thomas , Gonnermann Helge M. , Gardner James E. , Burgisser Alain , Hajimirza Sahand , Earley Tobias C. , Truong Nathan , Toledo Pamela
Published: February 2019

Coalescence during bubble nucleation and growth in crystal‐free rhyolitic melt was experimentally investigated, and the percolation threshold, defined as the porosity at which the vesicular melt first becomes permeable, was estimated. Experiments with bubble number densities between 1014 and 1015 m−3 were compared to four suites of rhyolitic Plinian pumices, which have approximately equal bubble number densities. At the same total porosity, Plinian samples have a higher percentage of coalesced bubbles compared to their experimental counterparts. Percolation modeling of the experimental samples indicates that all of them are impermeable and have percolation thresholds of approximately 80–90%, irrespective of their porosity. Percolation modeling of the Plinian pumices, all of which have been shown to be permeable, gives a percolation threshold of approximately 60%. The experimental samples fall on a distinct trend in terms of connected versus total porosity relative to the Plinian samples, which also have a greater melt‐bubble structural complexity. The same holds true for experimental samples of lower bubble number densities. We interpret the comparatively higher coalescence within the Plinian samples to be a consequence of shear deformation of the erupting magma, together with an inherently greater structural complexity resulting from a more complex nucleation process.
How the Transition Region Along the Cascadia Megathrust Influences Coseismic Behavior: Insights From 2‐D Dynamic Rupture Simulations
Authors: Ramos Marlon D. , Huang Yihe
Published: February 2019

There is a strong need to model potential rupture behaviors for the next Cascadia megathrust earthquake. However, there exists significant uncertainty regarding the extent of downdip rupture and rupture speed. To address this problem, we study how the transition region (i.e., the gap), which separates the locked from slow‐slip regions, influences coseismic rupture propagation using 2‐D dynamic rupture simulations governed by a slip‐weakening friction law. We show that rupture propagation through the gap is strongly controlled by the amount of accumulated tectonic initial shear stress and gap friction level. A large amplitude negative dynamic stress drop is needed to arrest downdip rupture. We also observe downdip supershear rupture when the gradient in effective normal stress from the locked to slow‐slip regions is dramatic. Our results justify kinematic rupture models that extend below the gap and suggests the possibility of high‐frequency energy radiation during the next Cascadia megathrust earthquake.
Singular Spectrum Analysis With Conditional Predictions for Real‐Time State Estimation and Forecasting
Authors: Ogrosky H. Reed , Stechmann Samuel N. , Chen Nan , Majda Andrew J.
Published: February 2019

Singular spectrum analysis (SSA) or extended empirical orthogonal function methods are powerful, commonly used data‐driven techniques to identify modes of variability in time series and space‐time data sets. Due to the time‐lagged embedding, these methods can provide inaccurate reconstructions of leading modes near the endpoints, which can hinder the use of these methods in real time. A modified version of the traditional SSA algorithm, referred to as SSA with conditional predictions (SSA‐CP), is presented to address these issues. It is tested on low‐dimensional, approximately Gaussian data, high‐dimensional non‐Gaussian data, and partially observed data from a multiscale model. In each case, SSA‐CP provides a more accurate real‐time estimate of the leading modes of variability than the traditional reconstruction. SSA‐CP also provides predictions of the leading modes and is easy to implement. SSA‐CP is optimal in the case of Gaussian data, and the uncertainty in real‐time estimates of leading modes is easily quantified.
Satellite‐Observed Changes in Mexico's Offshore Gas Flaring Activity Linked to Oil/Gas Regulations
Authors: Zhang Yuzhong , Gautam Ritesh , Zavala‐Araiza Daniel , Jacob Daniel J. , Zhang Ruixiong , Zhu Lei , Sheng Jian‐Xiong , Scarpelli Tia
Published: February 2019

Gas flaring is a commonly used practice in the oil and gas sector that leads to key air pollutant and greenhouse gas emissions. Here we use multipollutant (NO2, SO2) satellite observations from 2005 to 2017 to quantify gas flaring activity in Mexico's offshore production cluster, which produces ~50–70% of the country's oil and is among the world's largest oil fields. We estimate annual flared gas volume ranging from 5.5 to 20 × 109 m3 over the Mexican offshore corresponding to >40% associated gas production, which is significantly larger than for instance offshore United States where reportedly <3% of associated gas is flared. The 13‐year record of satellite‐derived gas flaring indicates a drastic increase until 2008 and a decline afterward. While the increased flaring is associated with efforts to enhance oil production, the post‐2008 decline is linked to an expanding capacity of associated gas utilization, providing a continuing opportunity to reduce flaring for environmental and economic benefits.
Nonlinearity in the North Pacific Atmospheric Response to a Linear ENSO Forcing
Authors: Jiménez‐Esteve B. , Domeisen D. I. V.
Published: February 2019

El Niño Southern Oscillation (ENSO) exerts a remote impact on the North Pacific and North American winter climate. Both observational and model studies have suggested nonlinearities in this teleconnection. However, it remains unclear if possible nonlinearities arise from the forcing strength or the forcing location in the tropical Pacific, or from factors external to the tropical Pacific. To separate these factors, an idealized model is forced with seasonally varying sea surface temperature with linearly varying strength at a fixed location. Whereas for moderate events the North Pacific response is more linear, strong events exhibit significant nonlinearity both in terms of the strength and location of the impact. The nonlinearity can be traced back to the relationship between sea surface temperature and tropical convection. Nonlinearity in the North Pacific response can have important impacts for long‐range prediction and for potential changes in the diversity of ENSO with climate change.
A Cool, Nutrient‐Enriched Eastern Equatorial Pacific During the Mid‐Pleistocene Transition
Authors: Robinson Rebecca S. , Jones Colin A. , Kelly Roger P. , Rafter Patrick , Etourneau Johan , Martinez Philippe
Published: February 2019

The emergence of high‐amplitude, low‐frequency glacial‐interglacial cycles during the mid‐Pleistocene climate transition (MPT; 800–1,200 ka) is associated with global cooling. In the eastern equatorial Pacific, sea surface temperatures cooled, and the upwelling‐induced cold tongue expanded significantly during the MPT. Here we use sedimentary records of iron, biogenic silica, and nutrient‐nitrogen consumption to evaluate biogeochemical changes hypothesized to accompany the cold tongue expansion. Our results suggest that the eastern equatorial Pacific of the MPT hosted surface waters with higher nitrate contents and biogenic silica production relative to the last 600 ka. Increased production occurred despite low iron supply. We attribute this to enhanced upwelling and nutrient enrichment of thermocline waters, both likely related to the northward migration of Southern Ocean fronts. The return of these fronts to their southward positions after the MPT may be associated with stronger drawdown of nutrients and, potentially, atmospheric CO2 in the Southern Ocean.