bluuebunny/crossref_metadata_2025_split huggingface dataset:
The importance of mineral determinations to PROFILE base cation weathering release rates: a case study
Authors: Casetou-Gustafson Sophie , Akselsson Cecilia , Hillier Stephen , Olsson Bengt A. 
Published: May 2019

Abstract. Accurate estimates of base cation weathering rates in forest
soils are crucial for policy decisions on sustainable biomass harvest levels
and for calculations of critical loads of acidity. The PROFILE model is one
of the most frequently used methods to quantify weathering rates, where the
quantitative mineralogical input has often been calculated by the A2M
(“Analysis to Mineralogy”) program based solely on geochemical data. The
aim of this study was to investigate how uncertainties in quantitative
mineralogy, originating from modeled mineral abundance and assumed
stoichiometry, influence PROFILE weathering estimate, by using measured
quantitative mineralogy by X-ray powder diffraction (XRPD) as a reference.
Weathering rates were determined for two sites, one in northern (Flakaliden)
and one in southern (Asa) Sweden. At each site, 3–4 soil profiles were
analyzed at 10 cm depth intervals. Normative quantitative mineralogy was
calculated from geochemical data and qualitative mineral data with the A2M
program using two sets of qualitative mineralogical data inputs to A2M: (1) a
site-specific mineralogy based on information about mineral identification
and mineral chemical composition as determined directly by XRPD and electron
microprobe analysis (EMPA), and (2) regional mineralogy, representing the
assumed minerals present and assumed mineral chemical compositions for large
geographical areas in Sweden, as per previous published studies. Arithmetic
means of the weathering rates determined from A2M inputs (WA2M)
were generally in relatively close agreement with those (WXRPD)
determined by inputs based on direct XRPD and EMPA measurements. The
hypothesis that using site-specific instead of regional mineralogy will
improve the confidence in mineral data input to PROFILE was supported for
Flakaliden. However, at Asa, site-specific mineralogies reduced the
discrepancy for Na between WA2M and WXRPD but produced
larger and significant discrepancies for K, Ca and Mg. For Ca and Mg the
differences between weathering rates based on different mineralogies could be
explained by differences in the content of some specific Ca- and Mg-bearing
minerals, in particular amphibole, apatite, pyroxene and illite. Improving
the accuracy in the determination of these minerals would reduce weathering
uncertainties. High uncertainties in mineralogy, due for example to different
A2M assumptions, had surprisingly little effect on the predicted weathering
of Na- and K-bearing minerals. This can be explained by the fact that the
weathering rate constants for the minerals involved, e.g. K feldspar and
micas, are similar in PROFILE. Improving the description of the dissolution
rate kinetics of the plagioclase mineral group as well as major K-bearing
minerals (K feldspars and micas) should be a priority to help improve future
weathering estimates with the PROFILE model.
“Using Crowd-Sourced Data to Explore Police-Related-Deaths in the United States (2000–2017): The Case of Fatal Encounters”
Authors: Finch Brian Karl , Beck Audrey , Burghart D. Brian , Johnson Richard , Klinger David , Thomas Kyla 
Published: May 2019

Objectives: We evaluated the Fatal Encounters (FE) database as an open-source surveillance system for tracking police-related deaths (PRDs).Methods: We compared the coverage of FE data to several known government sources of police-related deaths and police homicide data. We also replicated incident selection from a recent review of the National Violent Death Reporting System.Results: FE collected data on n = 23,578 PRDs from 2000–2017. A pilot study and ongoing data integration suggest greater coverage than extant data sets. Advantages of the FE data include circumstance of death specificity, incident geo-locations, identification of involved police-agencies, and near immediate availability of data. Disadvantages include a high rate of missingness for decedent race/ethnicity, potentially higher rates of missing incidents in older data, and the exclusion of more comprehensive police use-of-force and nonlethal use-of-force data—a critique applicable to all extant data sets.Conclusions: FE is the largest collection of PRDs in the United States and remains as the most likely source for historical trend comparisons and police-department level analyses of the causes of PRDs.
Sensitivity and Specificity of Alzheimer Type II Astrocytes in Hepatic Encephalopathy
Authors: Agarwal Apeksha N. , Mais Daniel D. 
Published: May 2019

Context.—
Hepatic encephalopathy (HE) is associated with presence of type II astrocytes in the brain on the basis of observations made in single uncontrolled cases. This finding was subsequently demonstrated by in vitro studies with replication of microenvironment of HE by increase in ammonia levels. However, no human studies have been done correlating HE with type II astrocytes.

Objective.—
To determine the sensitivity and specificity of type II astrocytes in HE.

Design.—
This is a retrospective cohort study in which cases and controls were included. A database search was conducted to identify potential cases of hepatic encephalopathy during a 3-year period, as well as concomitant cases with altered mental status from other causes, liver disease, both, and neither. The presence of HE was determined according to standard clinical criteria, and a coronal section of basal ganglia was selected for examination from each case. Type II astrocytes were enumerated over 20 random high-power fields (HPFs).

Results.—
Twenty-one patients with HE were identified, with 35 patient controls (18 females, 38 males). Among the patients with HE there was a mean of 19.8 type II astrocytes in 20 HPFs. Patients with altered mental status without HE had an average of 7.2 type II astrocytes per 20 HPFs, and for those without altered mental status, the average was 2.8. For patients with hepatic insufficiency without HE, the average was 11, while for patients with normal hepatic function, the average was 4.1. Overall, for those without HE, the average was 5.4 type II astrocytes per 20 HPFs.

Conclusions.—
At a cutoff of 5 or more type II astrocytes per 20 HPFs, sensitivity for HE was 85.7% and specificity was 68.6%. Alzheimer type II astrocytes were present in all cases of HE but were also present in a wide variety of patients without HE.
Promotion of growth and metal accumulation of alfalfa by coinoculation with Sinorhizobium and Agrobacterium under copper and zinc stress
Authors: Jian Liru , Bai Xiaoli , Zhang Hui , Song Xiuyong , Li Zhefei 
Published: May 2019

The Legume-Rhizobium symbiosis has been proposed as a promising technique for the phytoremediation of contaminated soils due to its beneficial activity in symbiotic nitrogen fixation. However, numerous studies have shown that excessive heavy metals reduce the efficiency of symbiotic nodulation with Rhizobium and inhibit plant growth. In this study, we aimed to evaluate the synergistic effects of IAA-producing bacteria and Rhizobium on Medicago lupulina growth under Cu and Zn stress. Pot experiments showed that 400 mg kg−1 Cu2 + and Zn2 + greatly inhibited plant growth, but dual inoculation of Medicago lupulina with Sinorhizobium meliloti CCNWSX0020 and Agrobacterium tumefaciens CCNWGS0286 significantly increased the number of nodules and plant biomass by enhancing antioxidant activities. Under double stress of 400 mg kg−1 Cu2 + and Zn2 +, the nodule number and nitrogenase activities of dual-inoculated plants were 48.5% and 154.4% higher, respectively, than those of plants inoculated with Sinorhizobium meliloti. The root and above-ground portion lengths of the dual-inoculated plants were 32.6% and 14.1% greater, respectively, than those of the control, while the root and above-ground portion dry weights were 34.3% and 32.2% greater, respectively, than those of the control. Compared with S. meliloti and A. tumefaciens single inoculation, coinoculation increased total Cu uptake by 39.1% and 47.5% and increased total Zn uptake by 35.4% and 44.2%, respectively, under double metal stress conditions. Therefore, coinoculation with Sinorhizobium meliloti and Agrobacterium tumefaciens enhances metal phytoextraction by increasing plant growth and antioxidant activities under Cu/Zn stress, which provides a new approach for bioremediation in heavy metal-contaminated soil.
Chemovariation and antibacterial activity of extracts and isolated compounds from species of Ixora and Greenea (Ixoroideae, Rubiaceae)
Authors: Buathong Raveevatoo , Chamchumroon Voradol , Schinnerl Johann , Bacher Markus , Santimaleeworagun Wichai , Kraichak Ekaphan , Vajrodaya Srunya 
Published: May 2019

Background
A large number of secondary metabolites can be obtained from plants used for traditional medicine in two related genera (Ixora and Greenea) in the subfamily Ixoroideae (Rubiaceae), but there are only a few detailed studies on their bioactivities. Therefore, the main goals of this study were to determine the antibacterial activities of lipophilic extracts from plants of some Ixora and Greenea species native to Thailand, and to isolate some pure compounds from those extracts. Moreover, we compared the occurrence of compounds in different plant parts of samples from different habitats to better understand their variation.

Methods
A total of 56 lipophilic extracts were obtained from the leaves, stem bark, and root bark of eight Ixora and two Greenea species collected at various locations in Thailand. Isolated compounds were identified using nuclear magnetic resonance. Antimicrobial activities were evaluated against four Gram-positive and nine Gram-negative human pathogenic bacterial strains.

Results
Extracts from I. javanica, I. nigricans, I. brunonis, and G. montana, along with isolated scopoletin, exhibited antibacterial activities against Gram-positive methicillin-resistant Staphylococcus aureus ATCC 43300, with minimum inhibitory concentration values ranging from 64 to 256 µg/mL. The occurrence of scopoletin, isofraxidin, and geniposidic acid in lipophilic extracts showed some variation among different plant parts and species.

Conclusions
Lipophilic extracts of Ixora and Greenea species have the potential to be developed as anti-Gram-positive agents, in particular to counter infections of methicillin-resistant S. aureus strains. The chemical profiles showed differences between floristic regions but similarity within the same plant parts.
Admissions criteria as predictors of first-term success at a chiropractic institution
Authors: Long Ashley N. , Chen P. Daniel 
Published: May 2019

Objective
To determine the relationship between admissions criteria and grade point average (GPA) at the conclusion of the first-term of study at a chiropractic institution.

Methods
Secondary data analysis was used on the Fall 2017 entering cohort of doctor of chiropractic students. Independent samples t-tests and ordinary least squares linear regression were used to explain the extent to which incoming undergraduate GPA, undergraduate chemistry grade, undergraduate anatomy and physiology grade, and age, respectfully, influenced the end-of-trimester GPA.

Results
Linear regression found each of the four independent variables (undergraduate GPA, undergraduate chemistry grade, undergraduate anatomy and physiology grade, and age) to be significant influencers of end-of-trimester-1 GPA with undergraduate GPA being the most statistically significant predictor (p &lt; .001).The difference in mean end-of-trimester GPAs for male and female students was not statistically significant. There also was no difference in mean end-of-trimester GPAs by race/ethnicity.

Conclusion
Current admissions requirements may need to emphasize incoming undergraduate GPA and target student support for older students. This study should be repeated for increased sample size, be performed at other chiropractic institutions, and consider additional cohorts to strengthen results.
Defect and Contact Passivation for Perovskite Solar Cells
Authors: Aydin Erkan , De Bastiani Michele , De Wolf Stefaan 
Published: May 2019

AbstractMetal‐halide perovskites are rapidly emerging as an important class of photovoltaic absorbers that may enable high‐performance solar cells at affordable cost. Thanks to the appealing optoelectronic properties of these materials, tremendous progress has been reported in the last few years in terms of power conversion efficiencies (PCE) of perovskite solar cells (PSCs), now with record values in excess of 24%. Nevertheless, the crystalline lattice of perovskites often includes defects, such as interstitials, vacancies, and impurities; at the grain boundaries and surfaces, dangling bonds can also be present, which all contribute to nonradiative recombination of photo‐carriers. On device level, such recombination undesirably inflates the open‐circuit voltage deficit, acting thus as a significant roadblock toward the theoretical efficiency limit of 30%. Herein, the focus is on the origin of the various voltage‐limiting mechanisms in PSCs, and possible mitigation strategies are discussed. Contact passivation schemes and the effect of such methods on the reduction of hysteresis are described. Furthermore, several strategies that demonstrate how passivating contacts can increase the stability of PSCs are elucidated. Finally, the remaining key challenges in contact design are prioritized and an outlook on how passivating contacts will contribute to further the progress toward market readiness of high‐efficiency PSCs is presented.
Carbon Nanotube/Polyolefin Elastomer Metacomposites with Adjustable Radio‐Frequency Negative Permittivity and Negative Permeability
Authors: Luo Hongchun , Qiu Jun 
Published: May 2019

AbstractMetacomposites have received significant interest over the past decade due to their unique double‐negative electromagnetic properties. Magnetic particles, conductive polymer, and carbon materials are the usual materals used to fabricate metamaterials with doube‐negative electromagnetic properties. Here, insulating polymer polyolefin elastomer is instead used as the matrix to construct such metacomposites. The composites are fabricated by using a swelling, bonding, and hot pressing process. Metacomposites in which 50 vol% binder and 3 vol%, 6 vol%, and 12 vol% multi‐walled carbon nanotubes are added show negative permittivity and permeability in the microwave frequency range. Additionally, the electromagnetic properties of the metacomposites can be effectively adjusted by changing the amount of binder and filler. Specifically, the distribution of carbon nanotubes in the matrix can be tuned and thus some composites can exhibit double‐negative properties after the hot pressing process, which indicates hot pressing is also an effective way to adjust electromagnetic performance. The first insulating‐polymer‐based double‐negative metamaterial is fabricated and new methods are examined to adjust its electromagnetic properties, which greatly expands the potential applications of metacomposites.
Comparative genomics of Bifidobacterium species isolated from marmosets and humans
Authors: Brown Celeste J. , Mtui Dorah , Oswald Benjamin P. , Van Leuven James T. , Vallender Eric J. , Schultz‐Darken Nancy , Ross Corinna N. , Tardif Suzette D. , Austad Steven N. , Forney Larry J. 
Published: May 2019

AbstractThe genus Bifidobacterium is purported to have beneficial consequences for human health and is a major component of many gastrointestinal probiotics. Although species of Bifidobacterium are generally at low relative frequency in the adult human gastrointestinal tract, they can constitute high proportions of the gastrointestinal communities of adult marmosets. To identify genes that might be important for the maintenance of Bifidobacterium in adult marmosets, ten strains of Bifidobacterium were isolated from the feces of seven adult marmosets, and their genomes were sequenced. There were six B. reuteri strains, two B. callitrichos strains, one B. myosotis sp. nov. and one B. tissieri sp. nov. among our isolates. Phylogenetic analysis showed that three of the four species we isolated were most closely related to B. bifidum, B. breve and B. longum, which are species found in high abundance in human infants. There were 1357 genes that were shared by at least one strain of B. reuteri, B. callitrichos, B. breve, and B. longum, and 987 genes that were found in all strains of the four species. There were 106 genes found in B. reuteri and B. callitrichos but not in human bifidobacteria, and several of these genes were involved in nutrient uptake. These pathways for nutrient uptake appeared to be specific to Bifidobacterium from New World monkeys. Additionally, the distribution of Bifidobacterium in fecal samples from captive adult marmosets constituted as much as 80% of the gut microbiome, although this was variable between individuals and colonies. We suggest that nutrient transporters may be important for the maintenance of Bifidobacterium during adulthood in marmosets.
Can the shock index be a reliable predictor of early mortality after trauma in older patients? A retrospective cohort study
Authors: Shibahashi Keita , Sugiyama Kazuhiro , Okura Yoshihiro , Hoda Hidenori , Hamabe Yuichi 
Published: May 2019

AimOlder patients have different physiological characteristics; thus, the reliability of the shock index (SI) to predict mortality could depend on age. We investigated whether the SI is a reliable predictor of early mortality in older patients and evaluated the clinical benefit of age in the interpretation of the SI.MethodsUsing data from the Japan Trauma Data Bank, we identified injured patients aged 20–84 years. Area under the receiver operating characteristic curve (AUC) was used to evaluate the discrimination ability of the SI to predict early mortality. A formula to determine the cut‐off for each age was derived using linear regression analysis. Performance of the new method was compared with that of the traditional SI cut‐off of ≥0.9 AUC.ResultsWe analyzed data from 146,802 patients. Early mortality was observed in 4% of patients. The AUC showed a significant negative correlation with age (Spearman's ρ = –0.97, P < 0.001), and it decreased from 0.788 (95% confidence interval [CI], 0.761–0.815) in the 20–24 years age group to 0.660 (95% CI, 0.643–0.676) in those aged 80–84 years. By adjusting for age in the SI interpretation, AUC significantly improved from 0.681 (95% CI, 0.675–0.688) to 0.695 (95% CI, 0.688–0.701) (P < 0.001).ConclusionsThe performance of the SI to predict mortality after trauma was significantly worse in older patients. Even if the SI cut‐off value was adjusted based on age, the decrease in performance was not sufficiently prevented. Our results indicated that clinicians should be cautious when using the SI in older patients.
Catalytic Kinetic Resolution by Enantioselective Aromatization: Conversion of Racemic Intermediates of the Barton–Zard Reaction into Enantioenriched 3‐Arylpyrroles
Authors: Zheng Sheng‐Cai , Wang Qian , Zhu Jieping 
Published: May 2019

AbstractRacemic 3,4‐dihydro‐2H‐pyrroles, hypothetical intermediates of the Barton–Zard reaction, were synthesized in a highly diastereoselective manner and fully characterized for the first time. Kinetic resolution of the dihydropyrroles with a quinine‐derived thiourea afforded the (+)‐3‐arylpyrrole products and recovered (+)‐3,4‐dihydro‐2H‐pyrroles with high efficiency (s‐factor up to 153). The resolved (+)‐3,4‐dihydro‐2H‐pyrroles underwent subsequent aromatization with a quinidine‐derived thiourea catalyst to afford (−)‐3‐arylpyrroles with excellent central‐to‐axial chirality transfer. In contrast to the well‐accepted Barton–Zard mechanism, the aromatization of the 3,4‐dihydro‐2H‐pyrroles in the presence of a bifunctional catalyst is believed to proceed by an unprecedented sequence involving syn elimination of HNO2 and aromatization.
Stable, Reactive, and Orthogonal Tetrazines: Dispersion Forces Promote the Cycloaddition with Isonitriles
Authors: Tu Julian , Svatunek Dennis , Parvez Saba , Liu Albert C. , Levandowski Brian J. , Eckvahl Hannah J. , Peterson Randall T. , Houk Kendall N. , Franzini Raphael M. 
Published: May 2019

AbstractThe isocyano group is a structurally compact bioorthogonal functional group that reacts with tetrazines under physiological conditions. Now it is shown that bulky tetrazine substituents accelerate this cycloaddition. Computational studies suggest that dispersion forces between the isocyano group and the tetrazine substituents in the transition state contribute to the atypical structure–activity relationship. Stable asymmetric tetrazines that react with isonitriles at rate constants as high as 57 L mol−1 s−1 were accessible by combining bulky and electron‐withdrawing substituents. Sterically encumbered tetrazines react selectively with isonitriles in the presence of strained alkenes/alkynes, which allows for the orthogonal labeling of three proteins. The established principles will open new opportunities for developing tetrazine reactants with improved characteristics for diverse labeling and release applications with isonitriles.
Synthesis of a novel magnetic nanocatalyst based on rhodium complex for transfer hydrogenation of ketone
Authors: Kooti M. , Nasiri E. 
Published: May 2019

A magnetic heterogeneous nanocatalyst based on novel rhodium complex is designed. The transfer hydrogenation of ketones with 2‐propanol as hydrogen donor and the rhodium complex as nanocatalyst was achieved. High yields of ketones under mild conditions were obtained from easily available precursors.
Electron beam‐induced crosslinking of silk fibers using triallyl isocyanurate for enhanced properties
Authors: Thite Amol G. , Krishnanand Kumar , Panda Prasanta K. 
Published: May 2019

ABSTRACTIn this paper, electron beam (EB) radiation‐induced crosslinking of silk fibers by triallyl isocyanurate was accomplished for the first time by exposing the silk fabric in an inert atmosphere. The effect of EB dose (100–300 kGy) on the degree of crosslinking was found to show correlation with sol–gel contents and confirmed by Charlesby–Pinner plot along with their chemical stability in different solvents. Uniform and homogeneous distribution of particles on the fiber surface was observed under a scanning electron microscope, and elemental composition of those particles was detected similar to the silk by energy‐dispersive X‐ray spectra. Chemical changes occurred due to EB irradiation and crosslinking in the silk polymer was affirmed by attenuated total reflectance–Fourier transform infrared spectroscopy. From the thermogravimetric analyses, the thermal stability of the irradiated fibers with respect to weight loss was found to have increased from 17 to 32% at higher temperature range. The changes in mechanical property, stiffness, water contact angle, and degree of crosslinking of silk proportionately change with respect to the EB dose. However, 200 kGy EB dose was found optimum based on physical, chemical, and thermal properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47888.