bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term impacts of grazing management on land degradation in a rural community of Southern Italy: Depopulation matters
Authors: Quaranta Giovanni , Salvia Rosanna , Salvati Luca , Paola Velia De , Coluzzi Rosa , Imbrenda Vito , Simoniello Tiziana
Published: February 2020

Depopulation and economic marginalization of rural districts have induced a progressive land abandonment in agricultural and pastoral districts. In Europe, areas at higher risk of farmland abandonment are characterized by low‐intensity pasture systems whose fate is strongly dependent on state incentives or subsidies to rural development promoting more sustainable land‐use trajectories. Especially in Southern Europe, undergrazing is the main driver of pasture degradation. In such a context, a land management preserving pasture resilience requires a wider knowledge about the impact of practices on the ecological characteristics of pastures and an improved understanding of complex socio‐environmental interactions underlying the adoption of such practices. Based on these premises, this study investigates the extent to which the past land management reflects the current state of agro‐pastoral systems in a local community of Southern Apennine (Basilicata, Italy). Based on a multi‐scale analysis integrating multiple sources of data and exploratory techniques, three land‐use trajectories with different implications for land degradation were identified: (a) areas completely abandoned, (b) areas with a decrease in grazing where the management system is remained unchanged, and (c) areas characterized by a decrease in grazing with changes in the management system. Results outline the importance of landscape history shaping (optimal and sub‐optimal) land management and the influence of landscape structure on livestock performances within different farm management types.
Assessing spatial patterns of soil erosion in a high‐latitude rangeland
Authors: Streeter Richard T. , Cutler Nick A.
Published: February 2020

High‐latitude areas are experiencing rapid change: we therefore need a better understanding of the processes controlling soil erosion in these environments. We used a spatiotemporal approach to investigate soil erosion in Svalbarðstunga, Iceland (66°N, 15°W), a degraded rangeland. We used three complementary datasets: (a) high‐resolution unmanned‐aerial vehicle imagery collected from 12 sites (total area ~0.75 km2); (b) historical imagery of the same sites; and (c) a simple, spatially‐explicit cellular automata model. Sites were located along a gradient of increasing altitude and distance from the sea, and varied in erosion severity (5–47% eroded). We found that there was no simple relationship between location along the environmental gradient and the spatial characteristics of erosion. Patch‐size frequency distributions lacked a characteristic scale of variation, but followed a power‐law distribution on five of the 12 sites. Present total eroded area is poorly related to current, site‐scale levels of environmental stress, but the number of small erosion patches did reflect site‐level stress. Small (<25 m2) erosion patches clustered near large patches. The model results suggested that the large‐scale patterns observed likely arise from strong, local interactions, which mean that erosion spreads from degraded areas. Our findings suggest that contemporary erosion patterns reflect historical stresses, as well as current environmental conditions. The importance of abiotic processes to the growth of large erosion patches and their relative insensitivity to current environmental conditions makes it likely that the total eroded area will continue to increase, despite a warming climate and reducing levels of grazing pressure.
Analysis of Liver Resection Versus Liver Transplantation on Outcome of Small Intrahepatic Cholangiocarcinoma and Combined Hepatocellular‐Cholangiocarcinoma in the Setting of Cirrhosis
Authors: De Martin Eleonora , Rayar Michael , Golse Nicolas , Dupeux Margot , Gelli Maximiliano , Gnemmi Viviane , Allard Marc Antoine , Cherqui Daniel , Sa Cunha Antonio , Adam Rene , Coilly Audrey , Antonini Teresa Maria , Guettier Catherine , Samuel Didier , Boudjema Karim , Boleslawski Emmanuel , Vibert Eric
Published: February 2020

This multicenter study compares the outcomes of patients with cirrhosis undergoing liver transplantation (LT) or liver resection (LR) between January 2002 and July 2015 who had intrahepatic cholangiocarcinoma (iCCA) or combined hepatocellular‐cholangiocarcinoma (cHCC‐CCA) found incidentally in the native liver. A total of 49 (65%) LT and 26 (35%) LR patients with cirrhosis and histologically confirmed iCCA/cHCC‐CCA ≤5 cm were retrospectively analyzed. LT patients had significantly lower tumor recurrence (18% versus 46%; P = 0.01), for which the median diameter of the largest nodule (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.02‐1.12]; P = 0.006) and tumor differentiation (HR, 3.74; 95% CI 1.71‐8.17; P = 0.001) were independently predictive. The LT group had significantly higher 5‐year recurrence‐free survival (RFS; 75% versus 36%; P = 0.004). In patients with tumors >2 cm but ≤5 cm, LT patients had a lower recurrence rate (21% versus 48%; P = 0.06) and a higher 5‐year RFS (74% versus 40%; P = 0.06). Independent risk factors for recurrence were LT (protective; HR, 0.23; 95% CI, 0.07‐0.82; P = 0.02), the median diameter of the largest nodule (HR, 1.10; 95% CI, 1.02‐1.73; P = 0.007), and tumor differentiation (HR, 4.16; 95% CI, 1.37‐12.66; P = 0.01). In the LT group, 5‐year survival reached 69% and 65% (P = 0.40) in patients with tumors ≤2 cm and >2‐5 cm, respectively, and survival was also comparable between iCCA and cHCC‐CCA patients (P = 0.29). LT may offer a benefit for highly selected patients with cirrhosis and unresectable iCCA/cHCC‐CCA having tumors ≤5 cm. Efforts should be made to evaluate tumor differentiation, and these results need to be confirmed prospectively in a larger population.
Chloride‐induced steel corrosion in alkali‐activated fly ash mortar: Increased propensity for corrosion initiation at defects
Authors: Gluth Gregor J. G. , Ebell Gino , Hlaváček Petr , Mietz Jürgen
Published: February 2020

Chloride contents at the steel–mortar interface that initiate steel corrosion were determined for carbon steel in alkali‐activated fly ash mortar for three different exposure conditions: exposure to 1 M NaCl solution; leaching in deionized water and then exposure to 1 M NaCl solution; and leaching in deionized water, aging in air at 20°C and natural CO2 concentration, and then exposure to 1 M NaCl solution. For comparison, a Portland cement mortar, exposed to 1 M NaCl solution, was studied. The median values of the corrosion‐initiating chloride contents (average over the full length of the rebar) in the alkali‐activated fly ash mortar varied between 0.35 and 1.05 wt% Cl with respect to binder, consistently lower than what was obtained for the Portland cement mortar, but with no clear trend regarding the exposure conditions. For most of the alkali‐activated fly ash mortar specimens, preferential corrosion at the connection between the working electrode and the external measurement setup was observed, while preferential corrosion did not occur for the Portland cement mortar. Scanning electron microscopy and auxiliary experiments in synthetic solutions indicated that this behavior was caused by inhomogeneities at the steel–mortar interface in the alkali‐activated mortar, likely due to its peculiar rheological properties in the fresh state.
Corrosion behaviour of steel in mortar with wood biomass ash
Authors: Serdar Marijana , Carević Ivana , Nardin Mateo , Štirmer Nina
Published: February 2020

The present study investigates the influence of partial cement substitution with biomass ash on the corrosion behaviour of steel embedded in the mortar. To evaluate this influence, corrosion parameters of steel in mortar exposed to tap water and 3.5 wt% NaCl solution were monitored over a period of 50 days. The electrochemical cell consisted of a steel plate as a working electrode, covered with a layer of mortar that was exposed to the testing solution. Open‐circuit potential and linear polarisation were used to monitor changes in corrosion behaviour, whereas electrical impedance spectroscopy was used to evaluate the conductivity of the matrix. Additional to corrosion parameters, the chloride migration coefficient was tested after 28 days. On the basis of the results, it was observed that mortars with biomass ash provide equal or better protection for embedded steel, compared with the reference mortar. Mortars that performed slightly better than the reference mortar and other mortars were prepared with ashes with a higher amount of pozzolanic oxides.
3D Printed Sugar‐Sensing Hydrogels
Authors: Bruen Danielle , Delaney Colm , Chung Johnson , Ruberu Kalani , Wallace Gordon G. , Diamond Dermot , Florea Larisa
Published: February 2020

The ability of boronic acids (BAs) to reversibly bind diols, such as sugars, has been widely studied in recent years. In solution, through the incorporation of additional fluorophores, the BA–sugar interaction can be monitored by changes in fluorescence. Ultimately, a practical realization of this technology requires a transition from solution‐based methodologies. Herein, the first example of 3D‐printed sugar‐sensing hydrogels, achieved through the incorporation of a BA–fluorophore pair in a gelatin methacrylamide‐based matrix is presented. Through optimization of monomeric cocktails, it is possible to use extrusion printing to generate structured porous hydrogels which show a measurable and reproducible linear fluorescence response to glucose and fructose up to 100 mm.
Association Between Lifestyle and Hypertriglyceridemic Waist Phenotype in the PREDIMED‐Plus Study
Authors: Fernández‐García José Carlos , Muñoz‐Garach Araceli , Martínez‐González Miguel Ángel , Salas‐Salvado Jordi , Corella Dolores , Hernáez Álvaro , Romaguera Dora , Vioque Jesús , Alonso‐Gómez Ángel M. , Wärnberg Julia , Martínez J. Alfredo , Serra‐Majem Luís , Estruch Ramón , Lapetra José , Pintó Xavier , Tur Josep A. , Garcia‐Rios Antonio , García Molina Laura , Gaforio José Juan , Matía‐Martín Pilar , Daimiel Lidia , Martín Sánchez Vicente , Vidal Josep , Prieto Lucia , Ros Emilio , Goñi Nuria , Babio Nancy , Ortega‐Azorin Carolina , Castañer Olga , Konieczna Jadwiga , Notario Barandiaran Leyre , Vaquero‐Luna Jessica , Benavente‐Marín Juan Carlos , Zulet M. Angeles , Sanchez‐Villegas Almudena , Sacanella Emilio , Gómez Huelgas Ricardo , Miró‐Moriano Leticia , Gimenez‐Gracia Mariano , Julibert Alicia , Razquin Cristina , Basora Josep , Portolés Olga , Goday Albert , Galmés‐Panadés Aina M. , López‐García Carmen M. , Moreno‐Rodriguez Anai , Toledo Estefanía , Díaz‐López Andrés , Fitó Montserrat , Tinahones Francisco J. , Bernal‐López M. Rosa ,   PREDIMED‐Plus Investigators
Published: February 2020

Objective

The hypertriglyceridemic waist (HTGW) phenotype is characterized by abdominal obesity and high levels of triglycerides. In a cross‐sectional assessment of PREDIMED‐Plus trial participants at baseline, HTGW phenotype prevalence was evaluated, associated risk factors were analyzed, and the lifestyle of individuals with metabolic syndrome and HTGW was examined.

Methods

A total of 6,874 individuals aged 55 to 75 with BMI ≥ 27 and < 40 kg/m2 were included and classified by presence (HTGW+) or absence (HTGW−) of HTGW (waist circumference: men ≥ 102 cm, women ≥ 88 cm; fasting plasma triglycerides ≥ 150 mg/dL). Analytical parameters and lifestyle (energy intake and expenditure) were analyzed.

Results

A total of 38.2% of the sample met HTGW+ criteria. HTGW+ individuals tended to be younger, have a greater degree of obesity, be sedentary, and be tobacco users. They had higher peripheral glucose, total cholesterol, and low‐density lipoprotein cholesterol levels; had lower high‐density lipoprotein cholesterol levels; and had increased prevalence of type 2 diabetes mellitus. Mediterranean diet (MedDiet) adherence and physical activity were greater in HTGW− patients. Age, BMI, tobacco use, total energy expenditure, hypertension, type 2 diabetes mellitus, and MedDiet adherence were associated with HTGW+.

Conclusions

HTGW is a highly prevalent phenotype in this population associated with younger age, higher BMI, tobacco use, and decreased MedDiet adherence. HTGW− individuals were more physically active with greater total physical activity, and fewer had hypertension.
Phase Control of Polyamide 6 via Extension‐Dominated Polymer Blend Reactive Extrusion
Authors: Chen Hao , Zhu Sunsheng , Maia João
Published: February 2020

Control of the crystalline phase transition of polymers is critical to improve mechanical properties and to achieve good levels of thermal properties in polymer engineering. Current methods control the transition process by using thermal methods that is, annealing above the glass transition temperature (Tg) to get the targeting crystalline phase. It requires precise control of the temperature and process time and is limited to a small scale. In contrast, a novel processing‐based method developed in our group by combining the use of reactive processing technique and extensional mixing elements (EME) allows different sizes of minor phase droplets in immiscible polymer blends to be achieved by controlling the degree of aggressiveness of the EME. The use of EME can confine polyamide crystalline structure into the γ‐phase from the α‐phase. The reactive processing benefits in stabilizing these droplets and in freezing the corresponding crystalline morphologies in droplets. Crystalline phase transition of the minor phase in these droplets is therefore observed as the size of droplet decreases from micro to submicron. Furthermore, phase transition can be precisely controlled by tuning additives and EME blocks. POLYM. ENG. SCI., 60:1019–1028, 2020. © 2020 Society of Plastics Engineers
Nephrotoxicity Risk and Clinical Effectiveness of Continuous versus Intermittent Infusion Vancomycin Among Patients in an Outpatient Parenteral Antimicrobial Therapy Program
Authors: Shakeraneh Pegah , Fazili Tasaduq , Wang Dongliang , Gilotra Tarvinder , Steele Jeffrey M. , Seabury Robert W. , Miller Christopher D. , Darko William , Probst Luke A. , Kufel Wesley D.
Published: February 2020

Study Objective

To compare rates of nephrotoxicity, time to nephrotoxicity onset, and clinical failure among patients who received continuous infusion (C‐I) or intermittent infusion (I‐I) vancomycin in an outpatient parenteral antimicrobial therapy (OPAT) program. Nephrotoxicity was defined as an increase in serum creatinine greater than 0.5 mg/dl or a 50% increase from baseline for two consecutive measurements while receiving vancomycin during OPAT. Clinical failure was defined as unplanned readmission, extension of therapy, or change in antibiotics.

Design

Single‐center propensity score‐matched retrospective cohort study.

Setting

OPAT clinic affiliated with two nearby hospitals.

Patients

We identified 300 patients who received C‐I or I‐I vancomycin for at least 1 week in the OPAT program between October 1, 2017, and March 31, 2019. Propensity score matching based on age, sex, and infection was performed to minimize differences in patient characteristics between groups.

Measurements and Main Results

After propensity score matching and exclusion criteria, 74 patients were included in each cohort. Continuous infusion vancomycin was associated with a 3.22‐fold decrease in nephrotoxicity risk (C‐I 6.8% [5/74 patients] vs I‐I 18.9% [14/74 patients]; odds ratio 3.22, 95% confidence interval 1.10–9.46, p=0.027) and a significantly slower onset to nephrotoxicity compared with I‐I (p=0.035). No statistically significant difference in clinical failure rates was observed between the C‐I and I‐I groups (13.5% [10/74 patients] vs 23.0% [17/74 patients], p=0.147).

Conclusion

In an OPAT setting, C‐I vancomycin was associated with a lower risk of and slower onset to nephrotoxicity than I‐I vancomycin; however, no statistically significant difference in clinical failure rates was observed with C‐I versus I‐I vancomycin.
Morphological transition of nanostructures of self‐assembled block copolymers by stimuli‐induced conformational changes in the hydrophilic block
Authors: Jeong Moon Gon , Kim Jiwon , Kwon Jun Ho , Kim Kyoung Taek
Published: February 2020

The morphological control of nanostructures created by the self‐assembly of macromolecular building blocks in solution has practical importance because the structural parameters of nanostructures greatly affect their physical and chemical behavior in solution, for example, pharmacokinetics. Herein, we report that the stimuli‐induced changes to the conformation of the hydrophilic polymer block of a block copolymer (BCP), in this case branched‐linear poly(ethylene glycol)‐b‐poly(styrene) BCPs, are translated to changes in the morphology of the BCP self‐assemblies in solution. Specifically, the cone angle between the poly(ethylene glycol) arms in the tri‐arm hydrophilic block equipped with pyridyl units in the scaffold can be changed by varying the self‐assembly conditions, thus affecting the packing parameter (p) of the BCP. Upon increasing the cone angle by protonating the pyridyl units, the self‐assembled BCP structures underwent changes consistent with a reduction in the p value. In contrast, the chelation of zinc metal cations (Zn2+) to the pyridyl groups resulted in the conformation of the hydrophilic block taking on a closed form, resulting in an apparent increase in the p value of the BCP. Our results could be applied to stimuli‐dependent morphological transitions of other self‐assembled BCP nanostructures in solution.
Experiment study on etching process of graphite electrode by DC hydrogen plasma
Authors: Long Lin , Zhou Weixing , Tang Jingfeng , Zhou Desheng
Published: February 2020

DC (direct current) graphite electrodes were used to investigate the hydrogen plasma etching characteristics. Results show that the intermittent spark is marked by physical etching, whereas glow discharge is marked by chemical etching. CH4 is the main gas product, together with the existence of C2H6, C2H4, C3H8, and C3H6. A detailed analysis of the 20‐mA glow discharge showed that the chemical reactions due to the plasma occur mainly through hydrogenation reactions on graphite defects, and different plasma action zones on the graphite also play different roles. Additionally, plasma gaseous reaction processes were analyzed through free radical reactions.
Effects of amendments and microtopography on created tidal freshwater wetland soil morphology and carbon
Authors: Ott Emily T. , Galbraith John M. , Daniels W. Lee , Aust W. Michael
Published: February 2020

Created wetlands used to mitigate impacts to natural wetlands often have lower organic matter, less microtopography, fewer hydric soil field indicators (HSFIs), and higher bulk density (BD) than natural wetlands. Organic matter amendments may improve soil properties soon after wetland construction, but long‐term effects are seldom studied. This study investigated changes with time in soil properties of a sandy freshwater tidal created wetland in the Coastal Plain of Virginia. During construction in 2003/2004, five compost and topsoil treatments were applied, along with pit–mound microtopography. Soil descriptions were made in 2005, 2007, and 2015; samples were taken in 2006 and 2015. Four years after wetland construction, 69% of sandy plots met one or more HSFIs (S5, S6), and 62% of loamy plots met an HSFI (F3). Plots with loamy topsoil additions exhibited greater horizon and structure development, HSFI stability, greater soil mass C (0–30 cm), and higher soil C accumulation. Average soil C accumulation to 30 cm was 2.86 Mg ha−1 yr−1 in topsoil plots. With time, soils became darker (lower value, chroma) and higher in A horizon total C, and grayer (lower chroma) in C horizons, regardless of treatment. In 2015, microtopographic pits had lower color value (2.4), chroma (1.9), BD (0.87 g cm−3), and higher total C (2.39%) than mounds. We recommend adding pit and mound microtopography to created wetlands for increasing diversity of habitat. Further study is needed to see if topsoil and compost amendments improve long‐term plant community development in sandy created wetlands and in other wetland types.
Get rich or die trying… finding revenue model fit using machine learning and multiple cases
Authors: Tidhar Ron , Eisenhardt Kathleen M.
Published: February 2020

Research Summary

While revenue models are strategically important, research is incomplete. Thus, we ask: “What is the optimal choice of revenue model?” Using a novel theory‐building method combining machine learning and multi‐case theory building, we unpack optimal revenue model choice for a wide range of products on the App Store. Our primary theoretical contribution is a framework of high‐performing revenue model‐activity system configurations. Our core insight is the fit between value capture (revenue models) and value creation (activities) at the heart of successful business models. Contrastingly, low‐performing products avoid complex value capture (i.e., freemium) and misunderstand value creation (e.g., overweight effort). Overall, we contribute a theoretically accurate and empirically grounded view of successful business models using a pioneering method for theory building using large, quantitative data sets.

Managerial Summary

Revenue models are critical for product performance. Yet, the high‐performing choice is often unclear. We combine machine learning with multiple‐case deep‐dives to unpack optimal revenue model choice for a wide range of products on the App Store, a significant setting in the digital economy. Our primary insight is that high‐performing products fit value capture (revenue models) and value creation (activity systems) to form coherent business models. Contrastingly, low‐performing products avoid complex value capture (i.e., freemium) and misunderstand value creation (e.g., overweight effort and price). We also identify the importance of user resources, marketing, offline brand, and product complexity for specific revenue models. Overall, we contribute a framework for the optimal choice of revenue model and spotlight the revenue model‐activity system configurations of successful business models.
Shaping Metallic Nanolattices: Design by Microcontact Printing from Wrinkled Stamps
Authors: Wang Xuepu , Sperling Marcel , Reifarth Martin , Böker Alexander
Published: February 2020

A method for the fabrication of well‐defined metallic nanostructures is presented here in a simple and straightforward fashion. As an alternative to lithographic techniques, this routine employs microcontact printing utilizing wrinkled stamps, which are prepared from polydimethylsiloxane (PDMS), and includes the formation of hydrophobic stripe patterns on a substrate via the transfer of oligomeric PDMS. Subsequent backfilling of the interspaces between these stripes with a hydroxyl‐functional poly(2‐vinyl pyridine) then provides the basic pattern for the deposition of citrate‐stabilized gold nanoparticles promoted by electrostatic interaction. The resulting metallic nanostripes can be further customized by peeling off particles in a second microcontact printing step, which employs poly(ethylene imine) surface‐decorated wrinkled stamps, to form nanolattices. Due to the independent adjustability of the period dimensions of the wrinkled stamps and stamp orientation with respect to the substrate, particle arrays on the (sub)micro‐scale with various kinds of geometries are accessible in a straightforward fashion. This work provides an alternative, cost‐effective, and scalable surface‐patterning technique to fabricate nanolattice structures applicable to multiple types of functional nanoparticles. Being a top‐down method, this process could be readily implemented into, e.g., the fabrication of optical and sensing devices on a large scale.
Nano‐Architectured Composite Anode Enabling Long‐Term Cycling Stability for High‐Capacity Lithium‐Ion Batteries
Authors: Kumar Praveen , Berhaut Christopher L. , Zapata Dominguez Diana , De Vito Eric , Tardif Samuel , Pouget Stéphanie , Lyonnard Sandrine , Jouneau Pierre‐Henri
Published: February 2020

Failure mechanisms associated with silicon‐based anodes are limiting the implementation of high‐capacity lithium‐ion batteries. Understanding the aging mechanism that deteriorates the anode performance and introducing novel‐architectured composites offer new possibilities for improving the functionality of the electrodes. Here, the characterization of nano‐architectured composite anode composed of active amorphous silicon domains (a‐Si, 20 nm) and crystalline iron disilicide (c‐FeSi2, 5–15 nm) alloyed particles dispersed in a graphite matrix is reported. This unique hierarchical architecture yields long‐term mechanical, structural, and cycling stability. Using advanced electron microscopy techniques, the nanoscale morphology and chemical evolution of the active particles upon lithiation/delithiation are investigated. Due to the volumetric variations of Si during lithiation/delithiation, the morphology of the a‐Si/c‐FeSi2 alloy evolves from a core‐shell to a tree‐branch type structure, wherein the continuous network of the active a‐Si remains intact yielding capacity retention of 70% after 700 cycles. The root cause of electrode polarization, initial capacity fading, and electrode swelling is discussed and has profound implications for the development of stable lithium‐ion batteries.
Ten‐Gram‐Scale Facile Synthesis of Organogadolinium Complex Nanoparticles for Tumor Diagnosis
Authors: Wei Zhenni , Jiang Zhenqi , Pan Chunshu , Xia Jianbi , Xu Kaiwei , Xue Ting , Yuan Bo , Akakuru Ozioma Udochukwu , Zhu Chengjie , Zhang Guilong , Mao Zheng , Qiu Xiaozhong , Wu Aiguo , Shen Zheyu
Published: February 2020

The market of available contrast agents for clinical magnetic resonance imaging (MRI) has been dominated by gadolinium (Gd) chelates based T1 contrast agents for decades. However, there are growing concerns about their safety because they are retained in the body and are nephrotoxic, which necessitated a warning by the U.S. Food and Drug Administration against the use of such contrast agents. To ameliorate these problems, it is necessary to improve the MRI efficiency of such contrast agents to allow the administration of much reduced dosages. In this study, a ten‐gram‐scale facile method is developed to synthesize organogadolinium complex nanoparticles (i.e., reductive bovine serum albumin stabilized Gd‐salicylate nanoparticles, GdSalNPs‐rBSA) with high r1 value of 19.51 mm−1 s−1 and very low r2/r1 ratio of 1.21 (B0 = 1.5 T) for high‐contrast T1‐weighted MRI of tumors. The GdSalNPs‐rBSA nanoparticles possess more advantages including low synthesis cost (≈0.54 USD per g), long in vivo circulation time (t1/2 = 6.13 h), almost no Gd3+ release, and excellent biosafety. Moreover, the GdSalNPs‐rBSA nanoparticles demonstrate excellent in vivo MRI contrast enhancement (signal‐to‐noise ratio (ΔSNR) ≈ 220%) for tumor diagnosis.
Promoting Student Agency in Writing
Authors: Barnes Jill
Published: February 2020

With increasing expectations on students regarding written communication, the promotion of student agency in writing is more important now than ever. Teachers must find ways to engage and empower all learners throughout the writing process so they can produce authentic and meaningful writing independently. To promote such agency, educators must allow students to do more of the work, even while scaffolding for students who need more support. Supporting students in ways that promote metacognition, using their own voice and ideas, pinpointing their individual needs, and encouraging student leadership throughout the writing process kindle students’ capacity and inclination to take initiative for their own achievement. The author presents strategies that teachers can use to promote student metacognition and agency during the writing processes while allowing students to keep their own writing identity and build independence.
NMR based metabolomic approach for evaluation of Vietnamese honey
Authors: Luong Dang Vu , Tam Nguyen Quang , Xuan Do Thi Thanh , Tai Nguyen Tien
Published: February 2020

Honey represents a natural, agricultural product endowed with valuable nutritional and pharmacological functions. Therefore, the classification and evaluation of honey has always been a challenge for chemical analysis, especially when honey adulteration is increasing. The traditional methods for quality control of honey is currently based on physicochemical methods, which is often relatively high cost and time‐consuming. NMR based metabolomics is a metabolomic fingerprinting approach for NMR data using chemometric tools. This combined approach can be apply in food analysis for origin discrimination, biomarker discovery and authenticity screening. The present study demonstrated the capability of the 1H NMR based metabolomics for evaluation of 27 NMR spectra of 09 selected honey samples from Viet Nam. 1H NMR analysis was conducted immediately on collected honey samples, without extraction. Unsupervised PCA multivariate data analysis, applied on 1H NMR experimental data, used to characterize and classify honey samples according to their origin and quality. Different metabolites specific for each botanical origins of honey samples also determined. The obtained results of the demonstration suggests that this combined approach could be useful to develop generally applicable metabolomic approaches to valuate honey products as well as other agricultural products.
Substituent effects on antioxidant activity of monosubstituted indole‐3‐carbinols: A DFT study
Authors: Van Quan Vo , Phu Ho Thi , Thao Pham Thi Thu , Nam Pham Cam
Published: February 2020

Indole‐3‐carbinol (I3C) is an indole compound with proven health benefits and thus potential preventive medicine and therapeutic applications. Here the origins of the substituent effects on the antioxidant activity of monosubstituted indole‐3‐carbinols (I3Cs) were studied in silico by calculating their thermochemical properties using the (RO)B3LYP/6‐311++G(2df,2p)//B3LYP/6‐311G(d,p) model chemistry. It was found that the electron withdrawing groups such as CF3, CN, COOH, COOMe can increase the bond dissociation energy (BDE) values of N‐H bonds and decrease the BDE(C8‐H) values, while the presence of the Br, Cl, F, Me, NMe2, NH2, NHMe, OH, OMe, Ph groups seems to decline the BDE(X‐H)s (X = N, C). It is worth noticing that a sequential electron transfer mechanism is responsible for these I3Cs with the strong electron donating groups including NMe2, NHMe and NH2, while a hydrogen atom transfer mechanism is likely favored for the remaining monosubstituted I3Cs. The kinetic study according to the HAT mechanism showed that the CH3OO• radical scavenging of 2‐NMe2‐I3C derivative has the highest rate constant (k = 1.93×1010 M‐1s‐1) and it is higher than that of typical antioxidants i.e. Trolox or ascorbic acid. Thus, the results appear to suggest that the N‐Br‐I3C and 2‐NMe2‐I3C compounds are potential antioxidants.
Study to improve the properties of polylactic acid by epoxidized crude rubber seed oil
Authors: Thuy Nguyen Thi , Nam Bui Xuan , Duc Vu Minh
Published: February 2020

The polylactic acid plasticized by epoxidized crude rubber seed oil (EcRSO) was prepared by using a Brabender mixer to improve the ductility of polylactic acid (PLA). The weight ratios of PLA/EcRSO were changed from 100/0 to 90/10. The tensile properties proved that the addition of EcRSO to PLA led to a strong increase in elongation at break (815 %) and a very strong increase in tensile toughness (1370 %), but a decrease in tensile strength. The plasticization of PLA with EcRSO lowered the Tg as well as cold‐crystallization temperature. The initial weight loss temperature grew from 261.8 to 308.8 oC and the weight loss at 380 oC of PLA reduced from 90.9 to 83.2 % with the presence of 5 wt.% EcRSO. Based on the overall results of this investigation, EcRSO could be used as an environmental friendly plasticizer to replace petroleum‐based plasticizers in improvement the overall properties of PLA.
Transition metal oxides as Pt‐free counter electrodes for liquid‐junction photovoltaic devices
Authors: Dao Van‐Duong , Quang Dang Viet , Vu Ngoc Hung , Vu Hong Ha Thi , Hoa Nguyen Duc , Duoc Vo Thanh , Van Hieu Nguyen , Nguyen Thi Hanh , Tran Nam Anh
Published: February 2020

This work presents the synthesis of the transition metal oxides (micro‐wheels composed of self‐assembled WO3 nanorods, SnO2 nanosheets, and Fe2O3 nanoparticles) by hydrothermal method. The synthesized catalysts are then applied for the regeneration of iodide ions from triiodide ions at counter electrodes (CEs) of dye‐sensitized solar cells (DSCs). As the results, the DSCs with low‐cost catalysts as WO3, SnO2, and Fe2O3 provided an efficiency of 4.36, 4.37 and 1.54 %, respectively, under 1 sun irradiation that is slightly lower than that of a cell with Pt electrode (5.86 %). This behavior is elucidated by electrochemical impedance measurements. These findings provide a strategy to develop low‐cost materials for DSC application.
Antioxidant vs. pro‐oxidant activities of quercetin in aqueous phase: A Density Functional Theory study
Authors: Thao Tran Hoang Dieu , Dung Vo Thi Ngoc , Dao Duy Quang
Published: February 2020

The antioxidant potential of quercetin (Quer) has been investigated for its radical scavenging activity and Cu(II) ion chelating one. Two intrinsic reactivities including bond dissociation enthalpy (BDE) and proton affinity (PA) were systematically calculated in water at the M05‐2X/6‐311++G(d,p) level of theory. All possible hydrated Quer–Cu(II) complexes were also performed to consider its indirect antioxidant activity via the meal ion chelation capacity. Furthermore, reaction enthalpies as well as Gibbs free energies of reactions between Quer‐Cu(II) complexes with O2•‐ and ascorbate anion (Asc‐) in forming corresponding Quer‐Cu(I) ones have also been investigated to draw the larger picture on reduction potential of Cu(II)to Cu(I) ions which may involve in Fenton‐like reactions leading to HO• radical formation.
Comparison of Merriam's Turkey Harvest Strategies and Survival in Northern Arizona
Authors: McCall Thomas C. , Clement Matthew J. , Wakeling Brian F.
Published: February 2020

We compared annual survival and hunting‐related mortality of female Merriam's turkey (Meleagris gallopavo merriami) between a period of relatively liberal hunting regulation (before 1990) and after implementation of a more conservative hunting regulation (after 1991) in Arizona, USA, to determine how those regulation changes affected hunting opportunity. Between January 2013 and October 2016, we used radiotelemetry to estimate survival and mortality rates of 185 female wild turkeys (60 juvenile, 125 adult) on 3 study areas in northern Arizona, which we compared with survival and mortality rates documented during an earlier study (1987–1990; Wakeling 1991). We used the nest survival approach in Program MARK to estimate survival and mortality rates for turkeys. Annual survival rate for radiomarked hens was 0.649 (95% CI = 0.597–0.702). Annual survival differed among Game Management Units, but not by season, year, age, or age × season interaction. Harvest rates were 0.024 (95% CI = 0.011–0.51) and 0.039 (95% CI = 0.022–0.071) for females during spring (Mar–May) and fall (Aug–Oct), respectively. The overall human‐caused mortality rate (i.e., fall harvest, spring harvest, unlawful take, wounding loss) was 0.073 (95% CI = 0.046–0.115). The decision to restrict fall turkey hunting opportunities using a regulated permit system had little effect on female turkey survival and hunting‐related mortality, but reduced the number of turkey hunters that could participate by 43%. © 2020 The Wildlife Society.
Bulk reconstruction for spinor fields in AdS/CFT
Authors: Foit Valentino F. , Kabat Daniel , Lifschytz Gilad
Published: February 2020

Abstract

We develop the representation of free spinor fields in the bulk of Lorentzian anti-de Sitter space in terms of smeared operators in the dual conformal field theory. To do this we expand the bulk field in a complete set of normalizable modes, work out the extrapolate dictionary for spinor fields, and show that the bulk field can be reconstructed from its near-boundary behavior. In some cases chirality and reality conditions can be imposed in the bulk. We study the action of the CFT modular Hamiltonian on bulk fermions to show that they transform with the expected spinor Lie derivative, and we calculate bulk-boundary two-point functions starting from CFT correlators.
Stability of neuronal avalanches and long-range temporal correlations during the first year of life in human infants
Authors: Jannesari Mostafa , Saeedi Alireza , Zare Marzieh , Ortiz-Mantilla Silvia , Plenz Dietmar , Benasich April A.
Published: February 2020

During infancy, the human brain rapidly expands in size and complexity as neural networks mature and new information is incorporated at an accelerating pace. Recently, it was shown that single-electrode EEG in preterms at birth exhibits scale-invariant intermittent bursts. Yet, it is currently not known whether the normal infant brain, in particular, the cortex, maintains a distinct dynamical state during development that is characterized by scale-invariant spatial as well as temporal aspects. Here we employ dense-array EEG recordings acquired from the same infants at 6 and 12 months of age to characterize brain activity during an auditory odd-ball task. We show that suprathreshold events organize as spatiotemporal clusters whose size and duration are power-law distributed, the hallmark of neuronal avalanches. Time series of local suprathreshold EEG events display significant long-range temporal correlations (LRTCs). No differences were found between 6 and 12 months, demonstrating stability of avalanche dynamics and LRTCs during the first year after birth. These findings demonstrate that the infant brain is characterized by distinct spatiotemporal dynamical aspects that are in line with expectations of a critical cortical state. We suggest that critical state dynamics, which theory and experiments have shown to be beneficial for numerous aspects of information processing, are maintained by the infant brain to process an increasingly complex environment during development.
InvestRM – Investieren in Rohstoffe am Balkan
Authors: Haindl Angelika
Published: February 2020

Der Balkan ist ein Gebiet mit geologischem Potential, besonders für die Selbstversorgung Europas mit kritischen Rohstoffen. In der gesamten Region fehlen relevante, gut aufbereitete Daten im Rohstoffsektor. Vorhandene Informationen über Vorkommen und Lagerstätten sind nicht immer objektiv, neutral und verifiziert. Dies macht es für Investoren schwierig, Investitionskalkulationen auf einer profunden Datenbasis durchzuführen. Genau hier setzt die Idee von „InvestRM“ an.

Am Beispiel Bosniens und Herzegowinas wird im Zuge des Projektes ein Online-Werkzeug entwickelt, welches auf eine umfangreche Datenbank aufbaut, die strukturierte Landesdaten sowie validierte geologische Informationen von rund 120 Vorkommen und Lagerstätten kritischer Rohstoffe enthält. Dabei handelt es sich um Vorkommen und Lagerstätten für den Abbau von Antimon, Bauxit (als Quelle für Seltene Erden), Fluorit und Magnesit.

Abgefragte Daten werden in wenigen Sekunden in einem PDF-Bericht in englischer Sprache zusammengestellt. Der Anwender erhält einen verlässlichen, modern aufbereiteten Auszug, welcher als Entscheidungsgrundlage für Investitionen fungieren kann.

Aktuell befindet sich das InvestRM-Tool gerade in der Testphase. Online, unter https:\\test.investrm.eu, können Interessierte bereits Berichte erstellen. Neben der Entwicklung des Webportals sind im Projekt auch Projektteam-Treffen und Informationstage (in Banja Luka, Prijedor, Tuzla und Zenica) eingeplant.
Stromal vascular fraction cells as biologic coating of mesh for hernia repair
Authors: Guillaume O. , Pérez-Köhler B. , Schädl B. , Keibl C. , Saxenhuber N. , Heimel P. , Priglinger E. , Wolbank S. , Redl H. , Petter-Puchner A. , Fortelny R.
Published: February 2020

Background

The interest in non-manipulated cells originating from adipose tissue has raised tremendously in the field of tissue engineering and regenerative medicine. The resulting stromal vascular fraction (SVF) cells have been successfully used in numerous clinical applications. The aim of this experimental work is, first to combine a macroporous synthetic mesh with SVF isolated using a mechanical disruption process, and to assess the effect of those cells on the early healing phase of hernia.

Methods

Human SVF cells combined with fibrin were used to coat commercial titanized polypropylene meshes. In vitro, viability and growth of the SVF cells were assessed using live/dead staining and scanning electron microscopy. The influence of SVF cells on abdominal wall hernia healing was conducted on immunodeficient rats, with a focus on short-term vascularization and fibrogenesis.

Results

Macroporous meshes were easily coated with SVF using a fibrin gel as temporary carrier. The in vitro experiments showed that the whole process including the isolation of human SVF cells and their coating on PP meshes did not impact on the SVF cells’ viability and on their capacity to attach and to proliferate. In vivo, the SVF cells were well tolerated by the animals, and coating mesh with SVF resulted in a decrease degree of vascularity compared to control group at day 21.

Conclusions

The utilization of SVF-coated mesh influences the level of angiogenesis during the early onset of tissue healing. Further long-term animal experiments are needed to confirm that this effect correlates with a more robust mesh integration compared to non-SVF-coated mesh.
Improvements in turbulence model realizability for enhanced stability of ocean forecast and its importance for downstream components
Authors: Brüning Thorger
Published: February 2020

The numerical stability of ocean circulation models is of high significance in operational forecasting. A substantial improvement in numerical stability of the 3D-ocean model HBM could be achieved by the implementation of new realizability criteria in the turbulence closure scheme. Realizability criteria which were already well documented for closure functions without double diffusion were therefore extended to those using double diffusion. A purely technical validation method called ε-test which is suitable for the detection of numerical stability problems is presented, and the effect of the development in turbulence model is demonstrated under severe weather conditions during extreme storm events. Evaluation of statistics of longer simulations indicate that instabilities appeared only locally and temporary; nevertheless, a significant impact on drift products relying on the current forecasts could be demonstrated, which underlines the importance of realizability in turbulence closure schemes in comprehensive operational model systems including ocean circulation and downstream drift components.
The oldest stage of the Outer Carpathian evolution in the light of Oxfordian–Kimmeridgian exotic clast studies (southern Poland)
Authors: Kowal-Kasprzyk Justyna , Krajewski Marcin , Gedl Przemysław
Published: February 2020

In the Late Jurassic, the rifting process led to the disintegration of the southern margin of the North European Platform and to the opening of the Outer Carpathian flysch basin sedimentary system. The initial sediments accumulated in the northern part of the basin are related to both the destruction and resedimentation of older platform deposits. Since the sedimentary succession of this pre-flysch phase was consumed by the Miocene subduction, its only traces are represented, nowadays, by clasts preserved as exotics in the succeeding flysch deposits. Our analysis of foraminifers as well as calcareous and organic dinoflagellate cysts found in these exotics confirms the Oxfordian–early Kimmeridgian timing of the platform phase that preceded the opening of the flysch basin. The exotics are represented by three main facies types: sponge–microbial limestones, oncoid–intraclastic–Crescentiellalimestones and fine-grained, biodetrital limestones withSaccocoma. These deposits are related to mid-ramp to outer-ramp settings. The land influence was rather weak, and these sedimentary settings were dominated by pelagic/hemipelagic accumulation. The studied facies are similar to facies types widely distributed over the northern shelf area of the Western Tethys (e.g., extra-Carpathian southern Poland, Carpathian Foredeep basement, southern Germany). In turn, coeval strata known from the part of the Magura Basin and of the Penninic–Pieninic Ocean, which were situated in more southern part of the Tethys, yielded different microfacies reflecting significant differences between the sedimentary settings of the study area and its southern extensions.
Curative-intent pancreas resection for pancreatic metastases: surgical and oncological results
Authors: Chikhladze Sophia , Lederer Ann-Kathrin , Kühlbrey Christian M. , Hipp Julian , Sick Olivia , Fichtner-Feigl Stefan , Wittel Uwe A.
Published: February 2020

Background

Pancreatic metastasis is a rare cause for pancreas surgery and often a sign of advanced disease no chance of curative-intent treatment. However, surgery for metastasis might be a promising approach to improve patients’ survival. The aim of this study was to analyze the surgical and oncological outcome after pancreatic resection of pancreatic metastasis.

Methods

This is a retrospective cohort analysis of a prospectively-managed database of patients undergoing pancreatic resection at the University of Freiburg Pancreatic Center from 2005 to 2017.

Results

In total, 29 of 1297 (2%) patients underwent pancreatic resection due to pancreatic metastasis. 20 (69%) patients showed metastasis of renal cell carcinoma (mRCC), followed by metastasis of melanoma (n = 5, 17%), colon cancer (n = 2, 7%), ovarian cancer (n = 1, 3%) and neuroendocrine tumor of small intestine (n = 1, 3%). Two (7%) patients died perioperatively. Median follow-up was 76.4 (range 21–132) months. 5-year and overall survival rates were 82% (mRCC 89% vs. non-mRCC 67%) and 70% (mRCC 78% vs. non-mRCC 57%), respectively. Patients with mRCC had shorter disease-free survival (14 vs. 22 months) than patients with other primary tumor entities.

Conclusion

Despite malignant disease, overall survival of patients after metastasectomy for pancreatic metastasis is acceptable. Better survival appears to be associated with the primary tumor entity. Further research should focus on molecular markers to elucidate the mechanisms of pancreatic metastasis to choose the suitable therapeutic approach for the individual patient.
A Closed-Cycle Miniature Dilution Refrigerator for a Fast-Cooldown 100 mK Detector Wafer Test Cryostat
Authors: Azzoni S. , May A. J. , Chase S. T. , Coppi G. , Kenny L. C. , Melhuish S. J. , Piccirillo L. , Suzuki A. , Wenninger J.
Published: February 2020

The forthcoming generation of cosmic microwave background polarization observatories is developing large format detector arrays which will operate at 100 mK. Given the volume of detector wafers that will be required, fast-cooldown 100 mK test cryostats are increasingly needed. A miniature dilution refrigerator (MDR) has been developed for this purpose and is reported. The MDR is precooled by a double-stage $${^3}\mathrm{He}$$3He–$${^4}\mathrm{He}$$4He Chase Research Cryogenics sorption refrigerator. The test cryostat based on this MDR will enable fast cooldown to 100 mK to support rapid feedback testing of detector wafers fabricated for the Simons Observatory. The MDR has been designed to provide a 100 mK stage to be retrocompatible with existing CRC10 sorption coolers, reducing the base temperature from 250 mK for the new generation of detectors. Other 250 mK cryostats can be retrofitted in the same way. This configuration will meet the cryogenic requirements for single-wafer testing, providing 5–10 $$\upmu \mathrm{W}$$μW of cooling power at 100 mk for over 8 h. The system operates in a closed cycle, thereby avoiding external gas connections and cold o-rings. No moving parts are required, with the system operated entirely by heaters.