bluuebunny/crossref_metadata_2025 huggingface dataset:
7T MR neurography‐ultrasound fusion for peripheral nerve imaging
Authors: Schreiber Stefanie , Schreiber Frank , Peter Alica , Isler Eser , Dörner Marc , Heinze Hans‐Jochen , Petri Suanne , Tempelmann Claus , Nestor Peter J. , Grimm Alexander , Vielhaber Stefan
Published: January 2020

Background

We present one patient with an initial diagnosis of Guillain‐Barré syndrome (GBS) and one with Charcot–Marie–Tooth disease (CMT) type 1A.

Methods

Both patients underwent ankle tibial nerve fusion‐imaging of high‐resolution ultrasound (HRUS) with 7T MR neurography (MRN).

Results

In GBS, the nerve was enlarged, T2‐hyperintense, and showed increased vascularization 21 months after symptom onset. In CMT1A, the enlarged nerve was T2‐isointense with normal endoneurial blood flow.

Conclusions

We demonstrate the utility of 7T‐MRN‐HRUS‐fusion‐imaging. In GBS, there was evidence of ongoing inflammation resulting in a changed diagnosis to acute‐onset chronic demyelinating polyradiculoneuropathy and maintenance of immunotherapy. By MRN‐HRUS‐fusion, patients with presumed peripheral axonal degeneration could be shown to display imaging markers associated with peripheral nervous system inflammation. Thus, more accurate identification of a treatable inflammatory component may become possible.
Kinetic detection of osmium(VI) ester intermediates during the OsO4‐mediated aqueous dihydroxylation of chloroethylenes
Authors: Gabričević Mario , Lente Gábor , Fábián István
Published: January 2020

The kinetics and mechanism of the cis dihydroxylation of cis‐1,2‐dichloroethylene, trans‐1,2‐dichloroethylene, and trichloroethylene by osmium tetroxide was studied systematically in aqueous solution. The stoichiometry of the process was determined based on the principle of continuous variation of reactant ratios with spectrophotometric detection. The results always showed 1:1 stoichiometry, which is in agreement with dihydroxylation. All three reactions were found to proceed in two distinct steps. The first step occurred on a time scale of seconds and was associated with a minor change in absorbance and was identified as the formation of a 1:1 adduct between the two reagents, which is the osmium(VI) ester that plays a decisive role in catalytic applications. This species is formed in an equilibrium that is very much shifted toward the reactants, so the osmium(VI) complex is a short‐lived intermediate of the process, which is detected kinetically, but its concentration is never high enough for structural characterization. The second reaction is accompanied by major spectral changes; it involves the formation of the final products. Our results clearly show that it is possible to detect the intermediate of the process by careful kinetic studies. It is also possible that the same strategy might be successful in other OsO4‐dependent dihydroxylation processes.
Substantially Improving Device Performance of All‐Inorganic Perovskite‐Based Phototransistors via Indium Tin Oxide Nanowire Incorporation
Authors: Hou Yue , Wang Liming , Zou Xuming , Wan Da , Liu Chang , Li Guoli , Liu Xingqiang , Liu Yufang , Jiang Changzhong , Ho Johnny C. , Liao Lei
Published: January 2020

All‐inorganic halide perovskites (IHPs) have attracted enormous attention due to their intrinsically high optical absorption coefficient and superior ambient stabilities. However, the photosensitivity of IHP‐based photodetectors is still restricted by their poor conductivities. Here, a facile design of hybrid phototransistors based on the CsPbBr3 thin film and indium tin oxide (ITO) nanowires (NWs) integrated into a InGaZnO channel in order to achieve both high photoresponsivity and fast response is reported. The metallic ITO NWs are employed as electron pumps and expressways to efficiently extract photocarriers from CsPbBr3 and inject electrons into InGaZnO. The obtained device exhibits the outstanding responsivity of 4.9 × 106 A W−1, which is about 100‐fold better than the previous best results of CsPbBr3‐based photodetectors, together with the fast response (0.45/0.55 s), long‐term stability (200 h in ambient), and excellent mechanical flexibility. By operating the phototransistor in the depletion regime, an ultrahigh specific detectivity up to 7.6 × 1013 Jones is achieved. More importantly, the optimized spin‐coating manufacturing process is highly beneficial for achieving uniform InGaZnO‐ITO/perovskite hybrid films for high‐performance flexible detector arrays. All these results can not only indicate the potential of these hybrid phototransistors but also provide a valuable insight into the design of hybrid material systems for high‐performance photodetection.
Shape Control of Monodispersed Sub‐5 nm Pd Tetrahedrons and Laciniate Pd Nanourchins by Maneuvering the Dispersed State of Additives for Boosting ORR Performance
Authors: Zhang Huaifang , Qiu Xiaoyu , Chen Yifan , Wang Shangzhi , Skrabalak Sara E. , Tang Yawen
Published: January 2020

It is a great challenge to simultaneously control the size, morphology, and facets of monodispersed Pd nanocrystals under a sub‐5 nm regime. Meanwhile, quantitative understanding of the thermodynamic and kinetic parameters to maneuver the shape evolution of nanocrystals in a one‐pot system still deserves investigation. Herein, a systematic study of the density functional theory (DFT)‐calculated adsorption energy, thermodynamic factors, and reduction kinetics on Pd growth patterns is reported by combining theory and experiments, with a focus on the dispersed state of additives. As pure models, monodispersed Pd tetrahedrons enclosed by (111) facets with a narrow size distribution of 4.9 ± 1 nm and a high purity approaching 98% can be obtained when using 1,1′‐binaphthalene (C20H14) +2NH3 as additives. Specifically, laciniate Pd nanourchins (Pd LUs) can evolve via anisotropic growth when replacing additive with dose‐consistent 1,1′‐binaphthyl‐2,2′‐diamine (C20H16N2, two NH2 binding in C20H14). Catalytic investigations show that the sub‐5 nm Pd tetrahedrons exhibit higher activity in both the oxygen reduction (Eonset = 1.025 V, E1/2 = 0.864 V) and formic acid oxidation reaction with respect to the Pd LUs and Pd black, which represents a great step for the development of well‐defined Pd nanocrystals with size in the sub‐5 nm regime as non‐Pt electrocatalysts.
Comparing the Effect of Mn Substitution in Sulfide and Sulfoselenide‐Based Kesterite Solar Cells
Authors: Lie Stener , Li Wenjie , Leow Shin Woei , Bishop Douglas M. , Gunawan Oki , Helena Wong Lydia
Published: January 2020

Cation substitution is one of the effective ways to improve Cu2ZnSn(S,Se)4 (CZTSSe) photovoltaic performance. However, the commonly reported substitutes, Ag and Cd, are not ideal as they detract from the earth‐abundant and nontoxic motivation of CZTSSe. Herein, the role of Mn substitution in sulfide and sulfoselenide films are compared in terms of optoelectronic properties and device performance. CZT(S,Se) + CMZT(S,Se) double‐layered structures are fabricated by a sol–gel spin‐coating method with variations in the CMZT(S,Se) layer thickness. It is found that a smaller amount of Mn is required to achieve the highest photovoltaic performance in sulfoselenide films in comparison with sulfide‐based films. All device parameters (particularly Voc and fill factor) of the sulfoselenide films are improved as compared with the sulfide system. Using a combination of capacitance–voltage, drive‐level capacitance profiling, and photoluminescence (PL), it is found that the sulfoselenide film has a smaller interface defect density and higher hole mobility and PL intensity, which suggest much more effective charge separation and transport. In contrast, in double‐layer sulfide films, Mn reduces the acceptor defect level of the absorber.
Autonomous Formation and Annealing of Colloidal Crystals Induced by Light‐Powered Oscillations of Active Particles
Authors: Altemose Alicia , Harris Aaron J. , Sen Ayusman
Published: January 2020

The front cover artwork is provided by the Sen group at Penn State (USA). The image shows how active Ag3PO4 particles herd inactive SiO2 particles into colloidal crystals that exhibit oscillatory motion. The crystals disperse then rejoin/reorganize, undergoing “autonomous annealing”. Read the full text of the Communication at 10.1002/syst.201900021.
Dynamic measurement of moisture content using microwaves for moisture evaluation of agricultural products
Authors: Kon Seitaro , Kato Yuto , Horibe Masahiro
Published: January 2020

This paper describes a dynamic measurement method using correlations between phase and amplitude changes of microwaves for the moisture content of agricultural products such as rice and wheat. The proposed method does not require the value of the bulk density and/or the mass of the target. Static and dynamic measurements of rice with different moisture contents were performed. The results of the dynamic measurements were in close agreement with those of the static measurements. The ratio of the amplitude change and phase shift is linearly dependent on the moisture content of rice for both the static and dynamic measurements. Furthermore, it is possible to measure wrapped silage samples with a high moisture content directly. To optimize the measurement frequency, the relationships between the moisture content and phase–amplitude correlation was evaluated. As a result, an optimized frequency was obtained. The proposed method is available under conditions such as the range of moisture content from 10 to 80% with one optimized frequency. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Mechanochemical Synthesis of Cu2MgSn3S8 and Ag2MgSn3S8
Authors: Heppke Eva Maria , Klenner Steffen , Janka Oliver , Pöttgen Rainer , Lerch Martin
Published: January 2020

Two new thiospinels of the type AI2BIICIV3SVI8 were successfully synthesized via a mechanochemical route using binary sulfides and sulfur. Cu2MgSn3S8 and Ag2MgSn3S8 are the first AI2BIICIV3SVI8 compounds with magnesium as divalent cation. The crystal structures of Cu2MgSn3S8 and Ag2MgSn3S8 were refined in the cubic space group Fd3m using X‐ray powder diffraction. According to UV/Vis measurements, a direct optical bandgap of ca. 1.65 eV was determined for both Cu2MgSn3S8 and Ag2MgSn3S8. Temperature‐dependent magnetic susceptibility measurements of the Cu2MgSn3S8 sample indicate diamagnetism. A 119Sn Mössbauer spectrum confirms the tetravalent state of tin, underlining the electron‐precise description.
Une aventure sociale et humaine: The Service des Centres Sociaux in Algeria, 1955–1962
Authors: Durham Brooke
Published: January 2020

The history of the Service des centres sociaux in Algeria brings together ideas about integration, fundamental education, and the existence of a unified Franco-Muslim community during the Algerian War. This chapter pairs the history of education and international development to study approaches to human development in Algeria before independence in 1962. Sanctioned by the Governor-General of Algeria, Jacques Soustelle, the centres sought to modernize the Algerian masses through improving literacy rates, and increasing Muslim Algerians’ access to medical and social services. Linked to the United Nations Educational, Scientific and Cultural Organization’s Fundamental Education Programs, the centres arose out of local initiatives to break down barriers between communities and to meet the needs of the most disenfranchised in the midst of colonial violence and injustice.
Einleitung
Authors: Willert Emanuel
Published: January 2020

Kollisionen und Lösungen von Stoßproblemen haben vielfältige Anwendungen in verschiedenen Bereichen von Physik, Technik und Medizin. Fasst man „Stoß“ im weiteren Sinn als kurzzeitige starke Belastung auf, betrifft das nicht nur Wechselwirkungen zwischen unverbundenen Teilen eines Systems (beispielsweise Billard-Kugeln), sondern auch dauerhafte Verbindungen (z. B. in Hüft- oder Kniegelenken beim Stolpern oder Springen).
Kontaktmechanische Grundlagen
Authors: Willert Emanuel
Published: January 2020

In diesem sehr umfangreichen Kapitel sind die Methoden und Lösungen der Mechanik von axialsymmetrischen Kontaktproblemen dargelegt, die später zur Behandlung des Stoßproblems herangezogen werden. Ausgehend von der statischen Fundamentallösung der Elastizitätstheorie für einen homogenen elastischen Halbraum werden Schritt für Schritt die später im Buch verwendeten, relevanten Teile der axialsymmetrischen Kontaktmechanik entwickelt und dabei unterschiedliche physikalische Eigenschaften und Effekte (Adhäsion, Reibung, Viskoelastizität, Inhomogenität und Plastizität) berücksichtigt.
Quasistatische ebene Stöße von Kugeln
Authors: Willert Emanuel
Published: January 2020

Nach der Behandlung des reinen Normalstoßproblems ist das folgende Kapitel dem allgemeinen Stoßproblem von Kugeln gewidmet. Im Rahmen der im zweiten und dritten Kapitel beschriebenen Annahmen ist diese Aufgabe äquivalent zu dem ebenen Stoß einer starren Kugel auf einen deformierbaren Halbraum (siehe Abb. 2.2).
Anhang
Authors: Willert Emanuel
Published: January 2020

In diesem Kapitel werden zunächst die Lösungen einiger Tangentialkontaktprobleme, basierend auf der elastischen Fundamentallösung, hergeleitet. Außerdem ist eine kurze Übersicht der im Buch verwendeten mathematischen Spezialfunktionen und eine einfache Implementierung des MDR-Modells zur Untersuchung des ebenen Stoßes mit Reibung einer starren Kugel auf einen inkompressiblen viskoelastischen Halbraum in der Programmiersprache der kommerziellen Software MATLAB gegeben.
Economic Constraints to the Intensification of Rainfed Lowland Rice in Laos
Authors: Newby Jonathan , Manivong Vongpaphane , Cramb Rob
Published: January 2020

Despite the widespread adoption of mechanised land preparation, improved varieties, and low levels of inorganic fertilisers, rainfed lowland rice production in Laos remains an economically marginal activity, with limited incentives for farmers to intensify production beyond household needs. This is a challenge for the government, which promotes rice intensification by setting high official yield targets. We analyse farmers’ decisions regarding the intensification of rainfed lowland rice systems in two lowland provinces—Savannakhet and Champasak. We demonstrate that farmers have selectively adopted a range of new technologies and continue to respond to changing incentives. However, this has largely involved the adoption of Low-Input, more labour-efficient, and more stable production systems rather than commercially oriented, High-Input, high-yield systems. We use activity budgeting and sensitivity analysis to explore the economic performance of several input scenarios, ranging from farmers’ practice to input levels required to achieve government policy targets. The budget models show that, given their resource endowments and the high degree of production and market risk they encounter, households in the rainfed lowlands have been rational in adopting a Low-Input system rather than intensifying rice production to achieve government yield and production targets. We argue that the strategy of diversifying livelihoods while maintaining a largely subsistence-oriented rice production system is likely to persist, given current economic trends.
The Role of Irrigation in the Commercialisation of Rice Farming in Southern Cambodia
Authors: Sareth Chea , Cramb Rob , Fukai Shu
Published: January 2020

This chapter explores constraints to rice-based farming systems in the rainfed lowlands of Cambodia and the role of different sources of irrigation in alleviating some of those constraints. The research was carried out in lowland districts in Takeo and Kampong Speu Provinces, representing a major lowland rice-growing region with high population density, small farm sizes, and severe production constraints. Three villages were selected with similar biophysical and socioeconomic environments but different degrees of access to irrigation. The comparison shows that on-farm and (where feasible) canal irrigation can greatly increase the intensity, diversity, and profitability of land use, without being seriously constrained by available family labour. However, the potential for irrigated cropping has not been fully realised due to scattering of plots, restricted investment in tube wells, and underinvestment in maintaining canals. Nevertheless, even these partially irrigated systems not only increased land and labour utilisation but improved soil properties, reduced the risk of a household rice-deficit, increased the production of a marketable surplus of rice, and increased the level and diversity of crop income. The resultant cash flow provided the necessary working capital to keep the cropping system turning over with minimal need for credit, while providing income for household needs. While outmigration from southern Cambodia will undoubtedly continue, the case studies show that the development of more intensive, diverse, and market-oriented farming systems based on on-farm irrigation can provide a promising alternative pathway for many rural households.
Contract Farming of High-Quality Rice in Kampong Speu
Authors: Keosothea Nou , Molyaneth Heng
Published: January 2020

Contract farming is seen as one of the policies to overcome current impediments to commercialisation in the Cambodian rice sector. The Angkor Kasekam Roongroeung Co. Ltd. (AKR) was the first agribusiness firm to implement contract farming of rice and currently claims to have over 50,000 contracted farmers in four provinces. The approach was later adopted by other development organisations. Little is known about rice contract farming in Cambodia in terms of its contractual arrangements, inclusiveness, benefits, and challenges. This study examined the inclusion of smallholder farmers and the nature of contractual arrangements, the benefits of contract farming for farmers, and the challenges faced by farmers and agribusiness firms. AKR was selected as a case study because the company operates the largest scale of rice contract farming in Cambodia. The study found that the rice contract farming scheme of AKR was inclusive of poor farmers with small farms, even those with less than one hectare. With access to the benefits of the scheme, contract farmers were able to increase their returns from rice farming. However, some flaws in the contractual arrangements and the requirement to deliver high-quality rice for the export market posed a number of challenges to both AKR and the participating farmers, some of which could be addressed through policy interventions. Overcoming these challenges will enhance the benefits of contract farming for both farmers and agribusiness firms and thus contribute to further commercialisation of the rice sector and rural poverty reduction.
Issues of Rice Policy in the Lower Mekong Basin
Authors: Cramb Rob
Published: January 2020

The commercialisation of rice farming in the Lower Mekong Basin has been at the centre of that region’s remarkable journey out of poverty and food insecurity since the 1970s. A development strategy that centred on opening rice farming to productivity-enhancing investments had the double effect of increasing the incomes of large numbers of poor rural households while generating a marketable surplus to supply the rapidly growing urban population at low prices. The growth in export demand further added to the incomes of rice farmers in the more productive parts of the Basin. Thus, a development pathway emerged that was driven by political necessity to be broadly based and inclusive. However, the very success of this pathway has created new policy issues, requiring adjustments in the long-term emphasis on the intensification of smallholder rice production. The growth in production has led to a decline in prices while costs have been increasing. This has led to pressure from rice farmers for price support. Related policy issues include the persistence of smallholdings, the growing preference for more diversified farming systems, the role of the processing and exporting sectors, and the changing physical environment in the Basin. This chapter examines policies influencing access to resources (specifically, to land, water, and technology), the management of farm activities (whether specialised in production of high-quality rice or diversified into production of non-rice crops), and the appropriation of value (as determined by interventions in the marketing and pricing of paddy and rice).
From Subsistence to Commercial Rice Production in Laos
Authors: Manivong Vongpaphane , Cramb Rob
Published: January 2020

Rice farming in Laos is the least commercialised within the Lower Mekong. Moreover, Laos has suffered the most from variability in production due to the high incidence of droughts and floods. Nevertheless, as in the region as a whole, there has been a remarkable transformation of rice-based farming systems and supply chains over recent decades. These farming systems have been undergoing a transition from subsistence-based to market-oriented production. Rice production is dominated by the rainfed lowland system and is still predominantly for subsistence production of glutinous rice, with only a small proportion marketed and even less exported. However, the cultivated area and especially the yield of both rainfed and irrigated rice have been increasing, contributing to the achievement of rice self-sufficiency at the national level. Moreover, rural livelihoods have become increasingly diversified as the economy of the region develops and opportunities for off-farm and non-farm employment increase.
Energy correlations in the end-point region
Authors: Korchemsky G.P.
Published: January 2020

Abstract

The energy-energy correlation (EEC) measures the angular distribution of the energy that flows through two calorimeters separated by some relative angle in the final state created by a source. We study this observable in the limit of small and large angles when it describes the correlation between particles belonging, respectively, to the same jet and to two almost back-to-back jets. We present a new approach to resumming large logarithmically enhanced corrections in both limits that exploits the relation between the energy correlations and four-point correlation functions of conserved currents. At large angle, we derive the EEC from the behaviour of the correlation function in the limit when four operators are light-like separated in a sequential manner. At small angle, in a conformal theory, we obtain the EEC from resummation of the conformal partial wave expansion of the correlation function at short-distance separation between the calorimeters. In both cases, we obtain a concise representation of the EEC in terms of the conformal data of twist-two operators and verify it by comparing with the results of explicit calculation at next-to-next-to-leading order in maximally supersymmetric Yang-Mills theory. As a byproduct of our analysis, we predict the maximal weight part of the analogous QCD expression in the back-to-back limit.
On stringy de Sitter spacetimes
Authors: Berglund Per , Hübsch Tristan , Minić Djordje
Published: January 2020

Abstract

We reexamine a family of models with a 3+1-dimensional de Sitter spacetime obtained in the standard tree-level low-energy limit of string theory with a non-trivial anisotropic axion-dilaton background. While such limiting approximations are encouraging but incomplete, our analysis reveals a host of novel features, and shows these models to relate standard and well understood supersymmetric string theory solutions. Finally, we conjecture that this de Sitter spacetime naturally arises by including more of the stringy degrees of freedom, such as a recently advanced variant of the non-commutative phase-space formalism, as well as the analytic continuation of a complex two-dimensional Fano variety arising as a small resolution in a Calabi-Yau 5-fold.
Prognostic Nomogram for Resected Pancreatic Adenocarcinoma: A TRIPOD‐Compliant Retrospective Long‐Term Survival Analysis
Authors: Xu Dong , Zhang Kai , Li Mingna , Neoptolemos J. P. , Wu Junli , Gao Wentao , Wu Pengfei , Cai Baobao , Yin Jie , Shi Guodong , Lu Zipeng , Jiang Kuirong , Miao Yi
Published: January 2020

Background

Prognostic prediction had been widely used in various cancer entities, from early screening to end‐stage patient caring. Currently, there is hardly any well‐validated nomogram which exists for long‐term survival prediction in pancreatic adenocarcinoma (PC) patients in a post‐surgery setting. Our objectives are to identify possible prognostic factors in PC patients following radical resection and to develop a prognostic nomogram based on independent survival predictors.

Methods

From 2009 to 2014, a total of 432 PC patients who underwent curative intended surgeries with complete follow‐up data were included in this current retrospective long‐term survival analysis. Clinicopathological data were extracted from medical records, and all missing values (percentage 0.9–8.3%) were imputed five times with the “PMM” method. Cox proportional hazards models were utilized. A nomogram was formulated based on results from the multivariate regression model so as to predict OS at 1‐, 2‐ and 3‐year as well as median OS. Validations, including discrimination and calibration, were carried out with 1000 bootstrap resamples. External validation was conducted in order to verify the accuracy of our nomogram at 1 and 2 years by utilizing the clinicopathological data of 122 PC patients who underwent curative intended surgeries in 2015 in our centre.

Results

Age, abdominal pain, back pain, tumour location, preoperative neutrophil–lymphocyte ratio, preoperative CA19‐9, tumour differentiation, microscopic nerve invasion, microscopic vascular invasion, T stage, lymph node ratio, M stage and adjuvant chemotherapy were all assembled into nomogram. The concordance index (C‐index) of internal and external validation was 0.702 and 0.688, respectively. The C‐index of the TNM staging system was 0.572 (P < 0.001 vs. nomogram).

Conclusion

Our prognostic nomogram based on clinicopathological parameters shows good performance in long‐term survival prediction in PC patients following radical surgery and could play a role in further clinical utilization.
The Efficacy of Prophylactic Negative Pressure Wound Therapy for Closed Incisions in Breast Surgery: A Systematic Review and Meta‐Analysis
Authors: Cagney David , Simmons Lydia , O'Leary Donal Peter , Corrigan Mark , Kelly Louise , O'Sullivan M. J. , Liew Aaron , Redmond Henry Paul
Published: January 2020

Background

Negative pressure wound therapy (NPWT) is a promising advance in the management of closed surgical incisions. NPWT application induces several effects locally within the wound including reduced lateral tension and improving lymphatic drainage. As a result, NPWT may improve wound healing and reduce surgical site complications. We aim to evaluate the efficacy of prophylactic application of NPWT in preventing surgical site complications for closed incisions in breast surgery.

Methods

This systematic review was reported according to PRISMA guidelines. The protocol was published in PROSPERO (CRD42018114625). Medline, Embase, CINAHL and Cochrane Library databases were searched for studies which compare the efficacy of NPWT versus non‐NPWT dressings for closed incisions in breast surgery. Specific outcomes of interest were total wound complications, surgical site infection (SSI), seroma, haematoma, wound dehiscence and necrosis.

Results

Seven studies (1500 breast incisions in 904 patients) met the inclusion criteria. NPWT was associated with a significantly lower rate of total wound complications [odds ratio (OR) 0.36; 95% CI 0.19–069; P = 0.002], SSI (OR 0.45; 95% CI 0.24–0.86; P = 0.015), seroma (OR 0.28; 95% CI 0.13–0.59; P = 0.001), wound dehiscence (OR 0.49; 95% CI 0.32–0.72; P < 0.001) and wound necrosis (OR 0.38; 95% CI 0.19–0.78; P = 0.008). There was no significant difference in haematoma rate (OR 0.8; 95% CI 0.19–3.2; P = 0.75). Statistically significant heterogeneity existed for total wound complications, but no other outcomes.

Conclusion

Compared with conventional non‐NPWT dressings, prophylactic application of NPWT is associated with significantly fewer surgical site complications including SSI, seroma, wound dehiscence and wound necrosis for closed breast incisions.
Stronger MIP formulations for the Steiner forest problem
Authors: Schmidt Daniel , Zey Bernd , Margot François
Published: January 2020

The Steiner forest problem asks for a minimum weight forest that spans a given number of terminal sets. We propose new cut- and flow-based integer linear programming formulations for the problem which yield stronger linear programming bounds than the two previous strongest formulations: The directed cut formulation (Balakrishnan et al. in Oper Res 37(5):716–740, 1989; Chopra and Rao in Math Prog 64(1):209–229, 1994) and the advanced flow formulation by Magnanti and Raghavan (Networks 45:61–79, 2005). We further introduce strengthening constraints and provide an example where the integrality gap of our models is 1.5. In an experimental evaluation, we show that the linear programming bounds of the new formulations are indeed strong on practical instances and that the related branch-and-cut algorithm outperforms algorithms based on the previous formulations.
MGUS Predicts Worse Prognosis in Patients with Coronary Artery Disease
Authors: Xu Zhao , Sun Yifeng , Xu Tianhong , Shi Yidan , Liang Lifan , Liu Peng , Ge Junbo
Published: January 2020

We performed a retrospective cohort study to analyze all 87 CAD patients with MGUS and 178 CAD patients without MGUS admitted in Zhongshan Hospital Fudan University from 2015 to 2017. Patients were followed up via regular patient visits or telephone, and the median follow-up period was 2.9 years. The end point of follow-up was the occurrence of major adverse cardiac events (MACE). CAD patients with MGUS had a higher risk of MACE than those without MGUS (log-rank P = 0.0015). After adjustment for other markers in the stepwise Cox regression model, MGUS was still related to the increasing risk of MACE incident (P = 0.002, HR = 2.308). Then, we constructed the nomogram based on the Cox regression model, and the concordance index (C-index) was 0.667. Hence, MGUS might be added into the risk model of CAD.
How is silicic acid transported in plants?
Authors: Exley Christopher , Guerriero Gea , Lopez Xabier
Published: January 2020

Plants accumulate silicon in their tissues as amorphous silica. The form of silicon taken up by plants is silicic acid, a neutral molecule that passes through membrane channels with water. After seminal work on rice identified an aquaporin that appeared to mediate the passage of silicic acid, several papers followed and classified similar channels (referred to as “transporters”) in a number of plant species. These channels have been described as essential for silicon uptake and specific for the metalloid. Herein, we critically review the published data on the characterisation of one channel in particular, Lsi1, and identify possible caveats in results and limitations in methods used. Our analysis does not support the suggestion that the identified channels are specific for silicic acid. Computational analyses of the size of the Lsi1 pore additionally suggest that it may not play a significant role in mediating the movement of silicic acid in planta. We suggest that to avoid further confusion, channels currently implicated in the transport of silicic acid in planta are not referred to as silicon-specific transporters. Future research including the use of molecular dynamics simulations will enable the unequivocal identification of channels involved in silicon transport in plants.
Alkaline Ethanol Oxidation Reaction on Carbon Supported Ternary PdNiBi Nanocatalyst using Modified Instant Reduction Synthesis Method
Authors: Cermenek Bernd , Genorio Boštjan , Winter Thomas , Wolf Sigrid , Connell Justin G. , Roschger Michaela , Letofsky-Papst Ilse , Kienzl Norbert , Bitschnau Brigitte , Hacker Viktor
Published: January 2020

Direct ethanol fuel cells (DEFC) still lack active and efficient electrocatalysts for the alkaline ethanol oxidation reaction (EOR). In this work, a new instant reduction synthesis method was developed to prepare carbon supported ternary PdNiBi nanocatalysts with improved EOR activity. Synthesized catalysts were characterized with a variety of structural and compositional analysis techniques in order to correlate their morphology and surface chemistry with electrochemical performance. The modified instant reduction synthesis results in well-dispersed, spherical Pd85Ni10Bi5 nanoparticles on Vulcan XC72R support (Pd85Ni10Bi5/C(II-III)), with sizes ranging from 3.7 ± 0.8 to 4.7 ± 0.7 nm. On the other hand, the common instant reduction synthesis method leads to significantly agglomerated nanoparticles (Pd85Ni10Bi5/C(I)). EOR activity and stability of these three different carbon supported PdNiBi anode catalysts with a nominal atomic ratio of 85:10:5 were probed via cyclic voltammetry and chronoamperometry using the rotating disk electrode method. Pd85Ni10Bi5/C(II) showed the highest electrocatalytic activity (150 mA⋅cm−2; 2678 mA⋅mg−1) with low onset potential (0.207 V) for EOR in alkaline medium, as compared to a commercial Pd/C and to the other synthesized ternary nanocatalysts Pd85Ni10Bi5/C(I) and Pd85Ni10Bi5/C(III). This new synthesis approach provides a new avenue to developing efficient, carbon supported ternary nanocatalysts for future energy conversion devices.
Assessment of water quality status of Doyang River, Nagaland, India, using Water Quality Index
Authors: Lkr Akumtoshi , Singh M. R. , Puro Neizo
Published: January 2020

The Doyang River of Wokha district, Nagaland, NE India, has a strong economic and traditional attachment to the local people. It provides sufficient fertile plains and slopes for cultivation, good grounds for community fishing and hunting. It is not only important for the people of Wokha but also for the state of Nagaland because of the rich natural resources it provides. This study was conducted to assess the Water Quality Index (WQI) of the Doyang River from eight selected sampling stations. Maximum WQI values were recorded during monsoon season in all the stations followed by pre-monsoon and post-monsoon. Sampling stations located in the upstream of the river experience deteriorating WQI due to the presence of hydroelectric dam, changing landuse practices, increasing settlements and deforestation in the catchment and river banks. The overall WQI values showed good water quality status indicating suitability for different human uses. The present study points out that pH, DO and BOD played a central role in affecting the WQI of the river; however, in case of nutrient elements no such significant roles were observed in affecting the water quality of the river. The condition of water quality in our present study felt the necessity to adopt proper management policy and conservation efforts along the riparian zones of Doyang River.
Analyzing multi-stakeholder collaborative governance practices in urban water projects in Addis Ababa City: procedures, priorities, and structures
Authors: Woldesenbet Wassihun Gebreegiziaber
Published: January 2020

Though different technical approaches have been applied, Addis Ababa water bodies are persistently facing problems that affect their biological, economic, sociological, and ecological assets. To fill the technical gaps, multi-stakeholder collaborative governance approaches are unfolding, in the academia, as the important tools or methods of dealing with water problems. Thus, the basic objective of this qualitative exploratory study is analyzing the processes and outcomes of multi-stakeholder collaboration structures on the governance of urban water projects, and developing potential pathways of building collaboration among stakeholders for the governance of water bodies. The results of this study show that the processes of multi-stakeholder dialogues are handicapped by the absence of prehistory of collaborations, asymmetrical pre-deliberation communication, and the representation of stakeholders by individuals with no experience or the required expertise, and the lack of willingness among stakeholders to engage in the process of dialogues. The activities of supervision, evaluation, river assessment programs, and the establishment of stable and secured governance frameworks are loaded in a few government sectors, leading to the eruption of multiple problems. On the other hand, the potential pathways of building strong collaboration among stakeholders require a systematic procedure that establishes legal, political, and administrative commonality among stakeholders. This guides to instill responsibility, ownership, and commitment on the leaders, directors, and experts to work with others. The study concludes that urban water problems could not be well addressed unless the governance structures are built in advance by making the pre-deliberation and deliberation processes that combine the principles of simplicity, symmetrical communication with all stakeholders, the appointment of experts, and the development of a regular collaboration system. Further, these would enable to govern water governance projects effectively by combining the ecological, social, political, and economic perspectives. Besides, considering cultural, legal, social, and political contexts and establishing individual and organization sensitive committees at various levels is crucial for sustainability and adaptability.
Comparative study of the explosion pressure characteristics of micro- and nano-sized coal dust and methane–coal dust mixtures in a pipe
Authors: Tan Bo , Liu Huilin , Xu Bin , Wang Tian
Published: January 2020

Coal dust explosion accidents often cause substantial property damage and casualties and frequently involve nano-sized coal dust. In order to study the impact of nano-sized coal on coal dust and methane–coal dust explosions, a pipe test apparatus was used to analyze the explosion pressure characteristics of five types of micro-nano particle dusts (800 nm, 1200 nm, 45 μm, 60 μm, and 75 μm) at five concentrations (100 g/m3, 250 g/m3, 500 g/m3, 750 g/m3, and 1000 g/m3). The explosion pressure characteristics were closely related to the coal dust particle size and concentration. The maximum explosion pressure, maximum rate of pressure rise, and deflagration index for nano-sized coal dust were larger than for its micro-sized counterpart, indicating that a nano-sized coal dust explosion is more dangerous. The highest deflagration index Kst for coal dust was 13.97 MPa/(m·s), indicating weak explosibility. When 7% methane was added to the air, the maximum deflagration index Kst for methane–coal dust was 42.62  MPa/(m·s), indicating very strong explosibility. This indicates that adding methane to the coal dust mixture substantially increased the hazard grade.
The homalonotid trilobiteBurmeisteriaSalter, 1865 in the Lower Devonian of Argentina: new data in the context of southwestern Gondwana
Authors: Rustán Juan José , Waisfeld Beatriz G. , Vaccari N. Emilio
Published: January 2020

The homalonotid trilobiteBurmeisteriaSalter, 1865 is revised from material from the Lower Devonian of central western Argentina (the Talacasto Formation in the Precordillera Basin). In contrast to other closely related Devonian marine basins from South America (mainly Bolivia, Brazil and Uruguay), the only species recognized in Argentina includeBurmeisteria herschelii(Murchison, 1839) andB.notica(Clarke, 1913). New observations on the structure of the carapace indicate that structures sometimes interpreted as granules with taxonomic meaning are, in fact, taphonomic characters that represent the fillings of pore canals exposed by decortication. The antero-ventral process of the rostral plate may be a locking device during enrollment, which allowed long-term defensive behavior with a minimum of muscular energy.Burmeisteriais an upper Silurian to Middle Devonian endemic representative of southwestern Gondwanan (Malvinokaffric) basins. In the Argentine Precordillera Basin, this genus is virtually restricted to a sandy, Pragian, stratigraphic interval capped by a marker bed first reported by Keidel in 1921.
The role of reference frames in memory recollection
Authors: Riva Giuseppe , Di Lernia Daniele , Serino Andrea , Serino Silvia
Published: January 2020

In this commentary on Bastin et al., we suggest that spatial context plays a critical role in the encoding and retrieval of events. Specifically, the translation process between the viewpoint-independent content of a memory and the viewpoint-dependent stimuli activating the retrieval (mental frame syncing) plays a critical role in spatial memory recollection. This perspective also provides an explanatory model for pathological disturbances such as Alzheimer's disease.
Interactions with the integrative memory model
Authors: Bastin Christine , Besson Gabriel , Delhaye Emma , Folville Adrien , Geurten Marie , Simon Jessica , Willems Sylvie , Salmon Eric
Published: January 2020

The integrative memory model formalizes a new conceptualization of memory in which interactions between representations and cognitive operations within large-scale cerebral networks generate subjective memory feelings. Such interactions allow to explain the complexity of memory expressions, such as the existence of multiples sources for familiarity and recollection feelings and the fact that expectations determine how one recognizes previously encountered information.
Teaching Chinese as a second or foreign language to non-Chinese learners in mainland China (2014–2018)
Authors: Gong Yang (Frank) , Gao Xuesong (Andy) , Lyu Boning
Published: January 2020

This review involved 60 articles chosen from 336 empirical studies identified in five leading journals on the learning and teaching of Chinese as a second or foreign language in mainland China during the period 2014–2018. The selected studies document Chinese researchers' efforts to improve the teaching and learning of the Chinese language in terms of language pedagogy, language learning and teacher development. We contend that these studies on the teaching and learning of Chinese as a second or foreign language (CSL/CFL) can contribute to the advancement of second/foreign language education theories even though they were largely conducted to address local needs and interests in the Chinese context. Unfortunately, the impact of these studies on international language education research and pedagogical development remains limited and peripheral. For this reason, this review concludes with recommendations for Chinese researchers and journal editors in the field of Chinese language teaching and learning research on how to promote quality empirical research and enhance their contributions to second/foreign language education research.
Early caregiving quality predicts consistency of competent functioning from middle childhood to adolescence following early psychosocial deprivation
Authors: Guyon-Harris Katherine L. , Humphreys Kathryn L. , Miron Devi , Tibu Florin , Fox Nathan A. , Nelson Charles A. , Zeanah Charles H.
Published: January 2020

Adverse developmental outcomes for some children following institutional care are well established. Removal from institutional care and placement into families can promote recovery. However, little is known about how positive outcomes are sustained across adolescence among children with histories of severe deprivation. The present study examined the caregiving conditions that are associated with attaining and maintaining competent functioning (i.e., outcomes within typical levels) from middle childhood to adolescence following exposure to early institutional care. The participants included children with and without a history of institutional care who had competence assessed at ages 8, 12, and 16 years across seven domains: family relationships, peer relationships, academic performance, physical health, mental health, substance use (ages 12 and 16 years only), and risk-taking behavior. The participants were grouped based on whether they were always versus not always competent and never versus ever competent at ages 8 through 16 years. Adolescents with a history of institutional care were less likely to be consistently competent than those who were family reared. Among those who were exposed to early institutional rearing, maintaining competent functioning from 8 to 16 years was associated with spending less time in institutions and receiving higher-quality caregiving early in life. Ensuring high quality early caregiving may promote competent functioning following early deprivation.
Incorporating Posterior‐Informed Approximation Errors Into a Hierarchical Framework to Facilitate Out‐of‐the‐Box MCMC Sampling for Geothermal Inverse Problems and Uncertainty Quantification
Authors: Maclaren Oliver J. , Nicholson Ruanui , Bjarkason Elvar K. , O'Sullivan John P. , O'Sullivan Michael J.
Published: January 2020

We consider geothermal inverse problems and uncertainty quantification from a Bayesian perspective. Our main goal is to make standard, “out‐of‐the‐box” Markov chain Monte Carlo (MCMC) sampling more feasible for complex simulation models by using suitable approximations. To do this, we first show how to pose both the inverse and prediction problems in a hierarchical Bayesian framework. We then show how to incorporate so‐called posterior‐informed model approximation error into this hierarchical framework, using a modified form of the Bayesian approximation error approach. This enables the use of a “coarse,” approximate model in place of a finer, more expensive model, while accounting for the additional uncertainty and potential bias that this can introduce. Our method requires only simple probability modeling, a relatively small number of fine model simulations and only modifies the target posterior—any standard MCMC sampling algorithm can be used to sample the new posterior. These corrections can also be used in methods that are not based on MCMC sampling. We show that our approach can achieve significant computational speedups on two geothermal test problems. We also demonstrate the dangers of naively using coarse, approximate models in place of finer models, without accounting for the induced approximation errors. The naive approach tends to give overly confident and biased posteriors while incorporating Bayesian approximation error into our hierarchical framework corrects for this while maintaining computational efficiency and ease of use.
A Detectable Anthropogenic Shift Toward Intensified Summer Hot Drought Events Over Northeastern China
Authors: Li Huixin , Chen Huopo , Sun Bo , Wang Huijun , Sun Jianqi
Published: January 2020

This study investigates the influence of external forcings on the various summer hot drought events (SHDEs) over northeastern China (NEC). SHDEs are represented by the probability‐based index (PI), which considers precipitation and temperature anomalies. The results show that SHDEs over NEC increased from 1961 to 2005, and the experiments for historical forcing (ALL), increased greenhouse gases emission forcing (GHG), and anthropogenic forcing (ANT) can largely reproduce the spatial and temporal features of the trends of SHDEs over NEC. Based on the optimal fingerprinting method, the impact of increased anthropogenic activities can be detected at the 90% confidence level. In addition, the attributable changes of PI in response to GHG and ANT forcings resemble the observation, implying that the increasing trends of SHDEs over NEC are primarily attributed to the increased anthropogenic activity. Furthermore, the occurrence probability of SHDEs over NEC will be further increased under different Representative Concentration Pathways in the future. Additional strict control regulations on GHG emissions are thus suggested to mitigate its impact on regional climate changes.