bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rare‐earth metal derivatives supported by aminophenoxy ligand: Synthesis, characterization and catalytic performance in lactide polymerization
Authors: Li Min , Zhang Jie , Chen Jue , Yao Yingming , Luo Yunjie 
Published: November 2019

A library of rare‐earth metal derivatives supported by an aminophenoxy ligand was prepared and their catalytic performance in lactide polymerization was investigated. It was found that the synthetic strategy had a profound effect on the formation of aminophenoxy rare‐earth metal complexes. Amine elimination between Ln[N(SiMe3)2]3(μ‐Cl)Li(THF)3 (Ln = Yb, Y) and 1 equiv. of the aminophenol [HONH] ([HONH] = ο‐OCH3‐C6H4NHCH2(3,5‐tBu2‐C6H2‐2‐OH)) in toluene gave the unexpected heterobimetallic bis(aminophenoxy) rare‐earth metal complexes [ON]2LnLi(THF)2 (Ln = Yb (1), Y (2)). When the reactions were carried out in THF and TMEDA, amine elimination produced the aminophenoxy rare‐earth metal amide complexes {[ON]LnN(SiMe3)2}2 (Ln = Yb (5), Y (6)) in ca 85% isolated yields. Complexes 5 and 6 could also be obtained from salt metathesis reaction of {[ON]LnCl(THF)}2 (Ln = Yb (3), Y (4)) with NaN(SiMe3)2 in a 1:2 molar ratio. In addition, treatment of complexes 3 and 4 with NaOAr (Ar = &bond;C6H4‐4‐tBu) and (SiMe3)2NC(NPri)2Na in 1:4 and 1:2 molar ratios provided the corresponding aminophenoxy rare‐earth metal derivatives {[ON](μ‐OAr)Ln(μ‐OAr)Na(THF)2}2 (Ln = Yb (7), Y (8)) and {[ON]Ln[(iPrN)2CN(SiMe3)2]}2 (Ln = Yb (9), Y (10)), respectively. These complexes were fully characterized, and their molecular structures were determined using single‐crystal X‐ray diffraction. Polymerization experiments showed that complexes 1, 2, 5, 6, 9 and 10 were highly active for the ring‐opening polymerization of l‐lactide in toluene, and complex 1 promoted l‐lactide polymerization in a controlled fashion. The polymerization of rac‐lactide initiated by the neutral aminophenoxy rare‐earth metal complexes 5, 6, 9 and 10 in THF afforded heterotactic polymers.
Dense georadar survey for a large‐scale reconstruction of the archaeological site of Pyrgi (Santa Severa, Rome)
Authors: Orlando Luciana , Michetti Laura M. , Belelli Marchesini Barbara , Papeschi Paolo , Giannino Fabio 
Published: November 2019

AbstractThe Etruscan site of Pyrgi extended over 10 ha along the Tyrrhenian coastline. Fieldwork has so far brought to light the sanctuary and a ceremonial complex at the southern edge of the settlement, whereas additional evidence is provided by a section cut by sea erosion across the site. The archaeological layer is about 2 m thick and includes dry masonry buildings arranged into lots; the most superficial features are disturbed by deep agricultural activities and the top layer includes scattered building material (limestone and tuff blocks). At this site, the efficacy of geophysical prospections are generally affected by the nearby presence of the beach's magnetic sand and the railway line. The use of dense ground penetrating radar (GPR) data proved to be the most suitable method in the mapping of buried archeological structures and made it possible to map out the topographic layout of the area which is currently under excavation. The dense three‐dimensional georadar (GPR) data highlight the presence of structures implanted at different topographic levels and provide preliminary information about the main building interventions and planimetric modifications inside the urban lots. The work was extremely useful for the future planning of the archaeological excavation as it makes it possible to reduce the costs and environmental impact of the archaeological activity. The georadar anomalies were confirmed by an archaeological test‐trench conducted in the surveyed area.
Promoting colonoscopy screening among low‐income Latinos at average risk of colorectal cancer: A randomized clinical trial
Authors: DuHamel Katherine N. , Schofield Elizabeth A. , Villagra Cristina , Sriphanlop Pathu , Itzkowitz Steven H. , Cotter Gina , Cohen Noah , Erwin Deborah O. , Winkel Gary , Thompson Hayley S. , Zauber Ann G. , Jandorf Lina H. 
Published: November 2019

BackgroundScreening colonoscopy (SC) for colorectal cancer (CRC) is underused by Latino individuals. The current randomized clinical trial examined the impact of 3 interventions: 1) patient navigation; 2) patient navigation plus standard Centers for Disease Control and Prevention print materials; and 3) patient navigation plus culturally targeted print materials for Latinos referred for SC. Demographic, personal and health history, and psychometric factors associated with SC also were examined.MethodsA total of 344 urban Latino individuals aged 50 to 85 years with no personal and/or immediate family history of CRC diagnosed before age 60 years, no personal history of a gastrointestinal disorder, no colonoscopy within the past 5 years, with insurance coverage, and with a referral for SC were consented. Participants were randomized to patient navigation (20%), patient navigation plus standard Centers for Disease Control and Prevention print materials (40%), and patient navigation plus culturally targeted print materials (40%). The completion of SC was assessed at 12 months.ResultsThe interventions had an overall SC rate of 82%. Counterintuitively, patients with an average income of <$10,000 were found to have higher SC rates (87%) than those with a greater income (75%).ConclusionsThe addition of standard or culturally targeted print materials did not appear to increase SC rates above those for patient navigation. Indeed, after controlling for other variables, culturally targeted print materials were found to be associated with lower SC rates among Puerto Rican individuals.
Exosome/microvesicle content is altered in leucine‐rich repeat kinase 2 mutant induced pluripotent stem cell‐derived neural cells
Authors: Candelario Kate M. , Balaj Leonora , Zheng Tong , Skog Johan , Scheffler Bjorn , Breakefield Xandra , Schüle Birgitt , Steindler Dennis A. 
Published: November 2019

AbstractExtracellular vesicles, including exosomes/microvesicles (EMVs), have been described as sensitive biomarkers that represent disease states and response to therapies. In light of recent reports of disease‐mirroring EMV molecular signatures, the present study profiled two EMVs from different Parkinson's disease (PD) tissue sources: (a) neural progenitor cells derived from an endogenous adult stem/progenitor cell, called adult human neural progenitor (AHNP) cells, that we found to be pathological when isolated from postmortem PD patients' substantia nigra; and (b) leucine‐rich repeat kinase 2 (LRRK2) gene identified patient induced pluripotent stem cells (iPSCs), which were used to isolate EMVs and begin to characterize their cargoes. Initial characterization of EMVs derived from idiopathic patients (AHNPs) and mutant LRRK2 patients showed differences between both phenotypes and when compared with a sibling control in EMV size and release based on Nanosight analysis. Furthermore, molecular profiling disclosed that neurodegenerative‐related gene pathways altered in PD can be reversed using gene‐editing approaches. In fact, the EMV cargo genes exhibited normal expression patterns after gene editing. This study shows that EMVs have the potential to serve as sensitive biomarkers of disease state in both idiopathic and gene‐identified PD patients and that following gene‐editing, EMVs reflect a corrected state. This is relevant for both prodromal and symptomatic patient populations where potential responses to therapies can be monitored via non‐invasive liquid biopsies and EMV characterizations.
The Effect of Boron Forms on the Crystallization Process of Lithium Carbonate
Authors: Lu Pengcheng , Song Xingfu , Chen Hang , Sun Yuzhu , Yu Jianguo 
Published: November 2019

AbstractThe present study investigates the effect of low concentrations of boron on the crystallization of lithium carbonate (Li2CO3). Experimental results indicate that the boron in brine mainly exists in the forms of boric acid (B(OH)3) and borate anion (B(OH)4−). Temperature and pH are critical factors to adjust the ratio of B(OH)3 and B(OH)4−. Meanwhile, the density functional theory calculation results suggest that the interaction of B(OH)4− with Li+ is stronger than that of B(OH)3 with Li+. Based on this result, the effect of boron on the crystallization of Li2CO3 is investigated and discussed at different added forms of boron, added amount of sodium hydroxide, temperatures, and concentrations of boron. B(OH)4− is proved to be the form of boron that has significant influence. Temperature and amount of sodium hydroxide have significant influence on the balance of B(OH)3 and B(OH)4−. The boron content of Li2CO3 significantly decreases as the temperature increases, and that at 80 °C is 133 ppm while that at 25 °C is 397 ppm. And that increases as nNaOH/nB increases. Finally, effect of addition of polyhydric alcohols on reducing boron entrainment is investigated.
Efficient coordination of almost blank subframes with coupling macro cells in heterogeneous networks
Authors: Wang You‐Chiun , Huang Bo‐Jyun 
Published: November 2019

SummaryHeterogeneous networking is an inevitable trend in mobile communication systems, where macrocells and small cells coexist to provide the service of wireless access. The technique of enhanced inter‐cell interference coordination (eICIC) is popularly used to mitigate signal interference among cells. A number of subframes are picked as almost blank subframes (ABSs), during which a macro‐cell base station suspends data transmissions to improve signal quality of small cells that it covers. Since the throughput of macro cells drops to zero in an ABS, how to decide the number of ABSs (ie, the ABS ratio) and their positions (ie, the ABS placement) is critical. Many studies implicitly consider that every small cell resides in only one macro cell and they manage ABSs for each individual macro cell accordingly. In practice, some macro cells may cover the same small cells (called coupling macrocells) which makes the management of their ABSs depend on each other. To address this issue, the paper proposes an efficient coordination of ABS with coupling macro cells (ECO) algorithm. It divides the network into component subnetworks depending on whether macro cells are coupling or not. Then, ECO computes the ABS ratios for the macro cells in each component subnetwork based on multiple factors, including data rate, traffic demand, and quality of service (QoS) support. Moreover, ECO jointly places the ABSs of coupling macro cells to shorten packet latency. Experimental results show that the ECO algorithm not only increases the network throughput but also reduces the loss rate of real‐time data.
Prevalence, correlates and comorbidities of feeding and eating disorders in a nationally representative sample of Iranian children and adolescents
Authors: Mohammadi Mohammad Reza , Mostafavi Seyed‐Ali , Hooshyari Zahra , Khaleghi Ali , Ahmadi Nastaran , Molavi Parviz , Armani Kian Alireza , Safavi Parvin , Delpisheh Ali , Talepasand Siavash , Hojjat Seyed Kaveh , Pourdehghan Parandis , Ostovar Rahim , Hosseini Seyed Hamzeh , Mohammadzadeh Soleiman , Salmanian Maryam , Alavi Seyyed Salman , Ahmadi Ameneh , Zarafshan Hadi 
Published: November 2019

AbstractObjectiveThis study investigated the prevalence of feeding and eating disorders, and identified their correlates and comorbidities among children and adolescents.MethodWe used the nationally representative sample of the Iranian Children and Adolescents' Psychiatric disorders (IRCAP) survey, with 30,532 participants randomly selected by a multistage cluster sampling method. We employed the kiddie schedule for affective disorders and schizophrenia‐present and lifetime version (K‐SADS‐PL) semi‐structured face‐to‐face interview to screen for any psychiatric disorders, including feeding and eating disorders, and associated factors. We used multivariate binary logistic regression to analyze the data.ResultsValid data from 27,111 participants were analyzed. The total prevalence of feeding and eating disorders among children and adolescents was 0.89 (0.81–1.10). In all types of feeding and eating disorders, the adjusted odds ratio was higher among girls (except binge‐eating disorder) and older adolescents but was lower among rural residents. The most common psychiatric comorbidities observed in children and adolescents with feeding and eating disorders were obsessive–compulsive disorder (20.2%), agoraphobia (20.2%), depressive disorder (16.4%), social phobia (10.1%), oppositional defiant disorder (10.1%), generalized anxiety disorder (9.4%), attention deficit hyperactivity disorder (7.5%), and conduct disorder (5.7%), which were significantly more common compared to their peers without feeding and eating disorders.DiscussionOlder age, female gender and living in an urban area are predisposing factors in feeding and eating disorders (in binge‐eating disorder, the male gender is a positive correlate). We suggest that future works pay attention to the role of gender, comorbidities and predisposing factors.
Silhouette width using generalized mean—A flexible method for assessing clustering efficiency
Authors: Lengyel Attila , Botta‐Dukát Zoltán 
Published: November 2019

AbstractCluster analysis plays vital role in pattern recognition in several fields of science. Silhouette width is a widely used index for assessing the fit of individual objects in the classification, as well as the quality of clusters and the entire classification. Silhouette combines two clustering criteria, compactness and separation, which imply that spherical cluster shapes are preferred over others—a property that can be seen as a disadvantage in the presence of complex, nonspherical clusters, which is common in real situations. We suggest a generalization of the silhouette width using the generalized mean. By changing the p parameter of the generalized mean between −∞ and +∞, several specific summary statistics, including the minimum, maximum, the arithmetic, harmonic, and geometric means, can be reproduced. Implementing the generalized mean in the calculation of silhouette width allows for changing the sensitivity of the index to compactness versus connectedness. With higher sensitivity to connectedness, the preference of silhouette width toward spherical clusters should reduce. We test the performance of the generalized silhouette width on artificial data sets and on the Iris data set. We examine how classifications with different numbers of clusters prepared by different algorithms are evaluated, if p is set to different values. When p was negative, well‐separated clusters achieved high silhouette widths despite their elongated or circular shapes. Positive values of p increased the importance of compactness; hence, the preference toward spherical clusters became even more detectable. With low p, single linkage clustering was deemed the most efficient clustering method, while with higher parameter values the performance of group average, complete linkage, and beta flexible with beta = −0.25 seemed better. The generalized silhouette allows for adjusting the contribution of compactness and connectedness criteria, thus avoiding underestimation of clustering efficiency in the presence of clusters with high internal heterogeneity.
Intercontinental trends in functional and phylogenetic structure of stream fish assemblages
Authors: Bower Luke M. , Winemiller Kirk O. 
Published: November 2019

AbstractUnderstanding of community assembly has been improved by phylogenetic and trait‐based approaches, yet there is little consensus regarding the relative importance of alternative mechanisms and few studies have been done at large geographic and phylogenetic scales. Here, we use phylogenetic and trait dispersion approaches to determine the relative contribution of limiting similarity and environmental filtering to community assembly of stream fishes at an intercontinental scale. We sampled stream fishes from five zoogeographic regions. Analysis of traits associated with habitat use, feeding, or both resulted in more occurrences of trait underdispersion than overdispersion regardless of spatial scale or species pool. Our results suggest that environmental filtering and, to a lesser extent, species interactions were important mechanisms of community assembly for fishes inhabiting small, low‐gradient streams in all five regions. However, a large proportion of the trait dispersion values were no different from random. This suggests that stochastic factors or opposing assembly mechanisms also influenced stream fish assemblages and their trait dispersion patterns. Local assemblages tended to have lower functional diversity in microhabitats with high water velocity, shallow water depth, and homogeneous substrates lacking structural complexity, lending support for the stress‐dominance hypothesis. A high prevalence of functional underdispersion coupled with phylogenetic underdispersion could reflect phylogenetic niche conservatism and/or stabilizing selection. These findings imply that environmental filtering of stream fish assemblages is not only deterministic, but also influences assemblage structure in a fairly consistent manner worldwide.
Capillary electrophoresis‐integrated immobilized enzyme microreactor with graphene oxide as support: Immobilization of negatively charged L‐lactate dehydrogenase via hydrophobic interactions
Authors: Li Xiaojuan , Yin Zhengri , Cui Xiujun , Yang Li 
Published: November 2019

AbstractWe report the first application of hydrophobic interaction between graphene oxide (GO) and negatively charged enzymes to fabricate CE‐integrated immobilized enzyme microreactors (IMERs) by a simple and reliable immobilization procedure based on layer by layer assembly. L‐lactate dehydrogenase (L‐LDH), which is negatively charged during the enzymatic reaction, is selected as the model enzyme. Various spectroscopic techniques, including SEM, FTIR, and UV‐vis are used to characterize the fabricated CE‐IMERs, demonstrating the successful immobilization of enzymes on the negatively charged GO layer in the capillary surface. The IMER exhibits excellent repeatability with RSDs of inter‐day and batch‐to‐batch less than 3.49 and 6.37%, respectively, and the activity of immobilized enzymes remains about 90% after five‐day usage. The measured Km values of pyruvate and NADH of the immobilized L‐LDH are in good agreement with those obtained by free enzymes. The results demonstrate that the hydrophobic interactions and/or π‐π stacking is significant between the GO backbone and the aromatic residues of L‐LDH and favorable to fabrication of CE‐integrated IMERs. Finally, the method is successfully applied to the determination of pyruvate in beer samples.
A new theoretical method for calculating front abutment stress during coal mining
Authors: Liu Hao , Wang Pu , Liu Yuting , Dai Jin , Yang Jiqiang 
Published: November 2019

AbstractThe calculation of abutment stress has always been the most important topic in safe underground mining and design. In this paper, based on the formation mechanism of abutment stress, combined with the mechanical properties of actual strata and the theory of elastic foundation beams, a structure model of overlying strata with an elastic foundation is established, and a new theoretical calculation method of abutment stress is proposed. The new calculation method takes into account the interaction of the overlying key strata and the effect on the transmission of the front abutment stress and then analyzes the stress patterns of multilayered key strata under the combined action of the bending moment, shear force, and nonuniform load and its transmission to the underlying strata. In addition, based on field observations of panel 10 305 in the Xinglongzhuang coalmine, the influence range, peak position, and variation trend of the front abutment stress before and after breaking of the overlying key strata are studied and verified. The results show that the influence range of the abutment stress remains unchanged after KS1 breaks (eg, from 0 to 180 m), and its peak position shifts forward from 8 to 19 m, while the influence range (0‐180 m) and its peak position (6‐8 m in front of coal wall) remain unchanged after KS2 breaks; the abutment stress decreases, and the maximum decrease is 3.9 MPa in the range of 0‐22 m ahead of the coal wall after KS1 breaks, while the maximum decrease in the abutment stress is 2.1 MPa in the range of 0‐71 m ahead of the coal wall after KS2 breaks. The results of the new calculation method are basically consistent with the field observations and the existing theoretical results, showing that the method has good adaptability and reliability and can provide a new theoretical basis for on‐site design and construction practices.
Effect of Artemisia sphaerocephala Krasch polysaccharide on the gelatinization and retrogradation of wheat starch
Authors: Li Xiaowen , Li Junjun , Yin Xiuxiu , Wang Xiaolong , Ren Tian , Ma Zhen , Li Xiaoping , Hu Xinzhong 
Published: November 2019

AbstractThe effect of Artemisia sphaerocephala Krasch polysaccharide (ASKP) on the gelatinization and retrogradation of wheat starch (WS) was studied. RVA results displayed that ASKP addition increased the setback values of WS, which indicated that ASKP might promote the short‐term retrogradation of WS. DSC and XRD results demonstrated that the retrogradation percentage of WS during long‐time storage significantly decreased with the addition of ASKP, suggesting the inhibition effect of ASKP on the long‐term retrogradation of WS. As shown in TPA test, ASKP addition increased the hardness of starch gel at the beginning but decreased it after 14 days’ storage. Results of FT‐IR revealed that ASKP could promote the water retention and intermolecular hydrogen bonding formation. With the addition of ASKP, the spin–spin relaxation time measured by LF‐NMR decreased from 358.47 ms to 274.15 ms, illustrating that the WS paste containing ASKP had higher water retention ability. Leached amylose content results manifested the interaction between WS and ASKP. In summary, ASKP has potential to be a modifier on the retrogradation of starch in food processing.
The modification of gelatin films: Based on various cross‐linking mechanism of glutaraldehyde at acidic and alkaline conditions
Authors: Lin Junjie , Pan Daodong , Sun Yangying , Ou Changrong , Wang Ying , Cao Jinxuan 
Published: November 2019

AbstractIn order to investigate the effect of glutaraldehyde (GTA) on the structure, mechanical properties and thermal stability of gelatin films, gelatin films modified by GTA at various pH (4.5, 6.5, and 11), were prepared. According to FTIR analysis, the reaction mechanism between GTA and gelatin was different at various pH. With the addition of GTA, the intermolecular forces (hydrogen bonds and ionic bonds) and triple helix structure of gelatin film were significantly disrupted. At pH 4.5, gelatin films modified by GTA showed the highest mechanical properties and thermal stability among all films, which tensile strength and residues in TGA up to 16.13 MPa and 15.05%, respectively. Therefore, an optimum pH was around 4.5 in gelatin films cross‐linked by GTA.
Intraoperative monitoring of placental blood flow after cesarean birth to diagnose placenta accreta spectrum disorder: A preliminary study
Authors: Ryo Eiji , Namai Shigenari , Seto Michiharu , Shiba Masahiro , Kido Koichiro , Ayabe Takuya 
Published: November 2019

The risk of placenta accreta spectrum disorder was high when intraplacental blood flow continued 15 minutes after childbirth following a cesarean delivery.