bluuebunny/crossref_metadata_2025 huggingface dataset:
MASS SPECTROMETRY ANALYSIS OF DRUGS OF ABUSE: CHALLENGES AND EMERGING STRATEGIES
Authors: Borden Scott A. , Palaty Jan , Termopoli Veronica , Famiglini Giorgio , Cappiello Achille , Gill Chris G. , Palma Pierangela
Published: February 2020

Mass spectrometry has been the “gold standard” for drugs of abuse (DoA) analysis for many decades because of the selectivity and sensitivity it affords. Recent progress in all aspects of mass spectrometry has seen significant developments in the field of DoA analysis. Mass spectrometry is particularly well suited to address the rapidly proliferating number of very high potency, novel psychoactive substances that are causing an alarming number of fatalities worldwide. This review surveys advancements in the areas of sample preparation, gas and liquid chromatography‐mass spectrometry, as well as the rapidly emerging field of ambient ionization mass spectrometry. We have predominantly targeted literature progress over the past ten years and present our outlook for the future. © 2020 Periodicals, Inc. Mass Spec Rev
Dosimetric accuracy of delivering SBRT using dynamic arcs on Cyberknife
Authors: Bedford James L. , Nill Simeon , Oelfke Uwe
Published: February 2020

Purpose

Several studies have demonstrated potential improvements in treatment time through the use of dynamic arcs for delivery of stereotactic body radiation therapy (SBRT) on Cyberknife. However, the delivery system has a finite accuracy, so that potential exists for dosimetric uncertainties. This study estimates the expected dosimetric accuracy of dynamic delivery of SBRT, based on realistic estimates of the uncertainties in delivery parameters.

Methods

Five SBRT patient cases (prostate A — conventional, prostate B — brachytherapy‐type, lung, liver, partial left breast) were retrospectively studied. Treatment plans were produced for a fixed arc trajectory using fluence optimization, segmentation, and direct aperture optimization. Dose rate uncertainty was modeled as a smoothly varying random fluctuation of ± 1.0%, ±2.0% or ± 5.0% over a time period of 10, 30 or 60 s. Multileaf collimator uncertainty was modeled as a lag in position of each leaf up to 0.25 or 0.5 mm. Robot pointing error was modeled as a shift of the target location, with the direction of the shift chosen as a random angle with respect to the multileaf collimator and with a random magnitude in the range 0.0–1.0 mm at the delivery nodes and with an additional random magnitude of 0.5–1.0 mm in between the delivery nodes. The impact of the errors was investigated using dose‐volume histograms.

Results

Uncertainty in dose rate has the effect of varying the total monitor units delivered, which in turn produces a variation in mean dose to the planning target volume. The random sampling of dose rate error produces a distribution of mean doses with a standard deviation proportional to the magnitude of the dose rate uncertainty. A lag in multileaf collimator position of 0.25 or 0.5 mm produces a small impact on the delivered dose. In general, an increase in the PTV mean dose of around 1% is observed. An error in robot pointing of the order of 1 mm produces a small increase in dose inhomogeneity to the planning target volume, sometimes accompanied by an increase in mean dose by around 1%.

Conclusions

Based upon the limited data available on the dose rate stability and geometric accuracy of the Cyberknife system, this study estimates that dynamic arc delivery can be accomplished with sufficient accuracy for clinical application. Dose rate variation produces a change in dose to the planning target volume according to the perturbation of total monitor units delivered, while multileaf collimator lag and robot pointing error typically increase the mean dose to the planning target volume by up to 1%.
A novel gamma GLM approach to MRI relaxometry comparisons
Authors: Kapre Rohan , Zhou Junhan , Li Xinzhe , Beckett Laurel , Louie Angelique Y.
Published: February 2020

Purpose

To demonstrate that constant coefficient of variation (CV), but nonconstant absolute variance in MRI relaxometry (T1,T2,R1,R2) data leads to erroneous conclusions based on standard linear models such as ordinary least squares (OLS). We propose a gamma generalized linear model identity link (GGLM‐ID) framework that factors the inherent CV into parameter estimates. We first examined the effects on calculations of contrast agent relaxivity before broadening to other applications such as analysis of variance (ANOVA) and liver iron content (LIC).

Methods

Eight models including OLS and GGLM‐ID were initially fit to data obtained on sulfated dextran iron oxide (SDIO) nanoparticles. Both a resampling simulation on the data as well as two separate Monte Carlo simulations (with and without concentration error) were performed to determine mean square error (MSE) and type I error rate. We then evaluated the performance of OLS/GGLM‐ID onR1repeatability and LIC data sets.

Results

OLS had an MSE of 4–5× that of GGLM‐ID as well as a type I error rate of 20–30%, whereas GGLM‐ID was near the nominal 5% level in the relaxivity study. Only OLS found statistically significant effects of MRI facility on relaxivity in anR1repeatability study, but no significant differences were found in a resampling, whereas GGLM was more consistent. GGLM‐ID was also superior to OLS for modeling LIC.

Conclusions

OLS leads to erroneous conclusions when analyzing MRI relaxometry data. GGLM‐ID factors in the inherent CV of an MRI experiment, leading to more reproducible conclusions.
Otoliths Reveal Spawning Ecology and Early Life History of Sympatric Catostomids
Authors: Clark Barkalow Stephani L. , Brandenburg Mary A. , Platania Steven P.
Published: February 2020

Differences in spawning ecology and early life history may influence the recruitment success of three sympatric catostomids in the Colorado River basin: the Bluehead Sucker Catostomus discobolus, Flannelmouth Sucker C. latipinnis, and federally endangered Razorback Sucker Xyrauchen texanus. In the San Juan River, all three species annually produce larvae, but only Bluehead and Flannelmouth suckers regularly recruit to the juvenile phase and older. Otolith microstructure analysis can determine age, growth rates, and spawning periodicity and may elucidate possible reasons for differences in recruitment among species. Larval suckers were collected from low-velocity habitats in the San Juan River in 2011; fish were measured, and ontogenetic phase and fish age were determined from otolith increment counts. Otolith age was used to determine hatch dates and spawning periodicity, calculate daily growth rates, and develop three candidate growth functions relating fish age and body length. Relative to Bluehead and Flannelmouth suckers, Razorback Suckers had a shorter spawning period, lower growth rate, and a higher proportion of the least developed ontogenetic phase. The small size of Razorback Suckers relative to other suckers may result in higher predation and lower prey acquisition, thus restricting their transition to more developed phases and limiting recruitment to the juvenile phase. Model ranking based on Akaike's information criterion (corrected for small sample size) was nearly identical for all growth functions. The early life history information we provide may guide flow releases in this regulated system to provide suitable backwater habitat and warmer water temperatures compatible with reproduction, growth, and survival of native catostomids, including the endangered Razorback Sucker. However, due to the limited temporal and geographic extent of samples used in this study, data presented herein are not inclusive of all conditions under which suckers may be present in the San Juan River.
Paddlefish Exploitation and Movements within the Mississippi River Basin
Authors: Devine Thomas E. , Tripp Sara J. , Kramer Nicholas W.
Published: February 2020

The Paddlefish Polyodon spathula is an ancient species that is native to the Mississippi River and its larger tributaries. This species exhibits a unique combination of morphology and life history characteristics that leaves it vulnerable to river modifications and potential overexploitation, which has led to population declines in portions of the historic range. Concern regarding unknown exploitation rates from recreational and commercial fisheries has increased in recent decades, and the Convention on International Trade of Endangered Species is now requesting information from state agencies regarding the sustainability of commercially harvested Paddlefish populations. The Missouri Department of Conservation addressed this, in part, through the implementation of a 5-year mark–recapture study to estimate exploitation and nonreporting rates, evaluate movement patterns, and provide a baseline estimate of abundance for Paddlefish in the Mississippi River basin. A total of 2,224 Paddlefish were jaw-banded, and 102 were also implanted with transmitters in the Mississippi River basin within the borders of Missouri. Of those, 139 Paddlefish were caught by commercial or recreational anglers and 92 were harvested, resulting in an average annual exploitation estimate of 2.5% (SE = 0.6). Jaw band returns and telemetry information demonstrated that Paddlefish moved great distances (maximum 2,359 km) and crossed many regulatory boundaries (14 states). Despite relatively low exploitation rate estimates, a precautionary adjustment of regulations is advised to protect Paddlefish through maturation and ensure sustainability. In addition, regulations for this species should be assessed across the entire Mississippi River basin, as they differ within and between regulatory authorities. A combination of population monitoring (e.g., exploitation and population dynamics) and telemetry efforts have potential to help inform future basin-wide management approaches.
Investigating the associations of mucosal P2Y6 receptor expression and urinary ATP and ADP concentrations, with symptoms of overactive bladder
Authors: Firouzmand Sepinoud , Ajori Ladan , Towse Jonathan , Allameh Farzad , Najafi Saman , Javed Saqib , John Babbin , Langley Stephen E. M. , Fry Christopher H. , Young John S.
Published: February 2020

Aim

To characterize purinergic signaling in overactive bladder (OAB).

Methods

Mucosal biopsies were taken by flexible cystoscopy from patients with storage symptoms referred to Urology Departments of collaborating hospitals. Immunohistochemistry (n = 12) and Western blot analysis (n = 28) were used to establish the qualitative and quantitative expression profile of P2Y6 in human mucosa. Participants from the general population provided a mid‐stream urine sample. Bioluminescent assays were used to quantify adenosine triphosphate (ATP; n = 66) and adenosine diphosphate (ADP; n = 60) concentrations, which were normalized to creatinine (Cr) concentration. All participants completed a questionnaire (International Consultation on Incontinence Questionnaire – Overactive Bladder) to score urinary symptoms of OAB.

Results

P2Y6 immunoreactivity, more prominent in the urothelium (colocalized with the uroepithelial marker pan‐cytokeratin), was more greatly expressed in OAB compared to age‐ and sex‐matched controls (benign prostatic hyperplasia) without OAB symptoms. Mucosal P2Y6 was positively correlated only with incontinence (P = .009). Both urinary ATP and its hydrolysis product, ADP, an agonist to P2Y6, were positively correlated with total OAB symptom score (P = .010 and P = .042, respectively).

Conclusions

The positive correlation of P2Y6 only with incontinence may indicate a different phenotype in OAB wet and warrants further investigation. Positive correlations of ATP and ADP with total OAB symptom score demonstrate upregulation in purinergic signaling in OAB; shown previously only in animal models. Further research is required to validate whether purinoceptors are indeed new therapeutic targets for this highly prevalent symptom complex.
“The right place and the right time”: A qualitative study of the decision‐making process of self‐initiated HIV testing among young adults
Authors: Adebayo Oluwamuyiwa W. , Williams Jessica R. , Garcia Ana
Published: February 2020

Young adults continue to have very low rates of human immunodeficiency virus (HIV) testing, which contribute to transmission, late diagnoses, and poor health outcomes. The access and uptake of HIV testing among young adults can be improved by promoting self‐initiated testing (i.e., testing without the immediate recommendation of a clinician). Little is known, however, about how young adults self‐initiate HIV testing. The purpose of this study was to explore the decision‐making process of young adults who self‐initiated HIV testing. A qualitative descriptive study was conducted with 30 young adults aged 18–24 years. The findings from this study describe how young adults acknowledge their vulnerability to HIV infection and navigate the process of deciding to self‐initiate testing. Some subcategories include Self‐Convincing, Conversation Prompts, and The Right Place and Right Time. Findings from this study are pivotal for subsequent studies to further understand self‐initiated HIV testing among young adults and design targeted interventions that will improve testing uptake.
Diffusion models over the life cycle of an innovation: A bottom‐up and top‐down synthesis approach
Authors: Wang Conghu , Li Xiaoming , Ma Wenjuan , Wang Xiaopeng
Published: February 2020

The diffusion models tend to be tested individually in isolation and remain the same over time for the studied innovations in the literature. Moreover, there is growing interest to learn from other countries in our current age of globalization. Therefore, this paper chooses the innovation of public resources trading platforms in China to fulfill above literature gaps. We have examined key events and the issuances of related laws and regulations by Chinese governments. Our contributions are twofold: (a) Our analysis and results show that the diffusion models evolve over the different stages of a life cycle of an innovation, contrasting to the literature results that diffusion models remain the same for their studied innovations. Due to major diverse characteristics among different adopter categories over a life cycle of an innovation, we argue that it is appropriate and necessary to apply different diffusion models on different adopter categories, which is missing in the current literature. (b) We find a first bottom‐up and then top‐down synthesis approach as an effective, efficient diffusion process for both fitting local needs (i.e., effective) and adopting innovations rapidly nationwide (i.e., efficient).
Polyethylene Nanocomposites with Ni, Co, and Fe Carbon‐Based Magnetic Fillers
Authors: Nisar Muhammad , Thue Pascal S. , Heck Cesar A. , Geshev Julian , Lima Eder C. , Galland Griselda Barrera
Published: February 2020

In the present study, the effect of Ni, Co, and Fe carbon‐based magnetic fillers (Ni‐C, Co‐C, and Fe‐C) was investigated on the magnetic, mechanical, thermal, and morphological properties of polyethylene nanocomposites. The in situ polymerization technique was used to prepare nanocomposites of polyethylene from the ethylene monomer introducing small amounts of filler ranging from 1 to 2 wt.%. The metal‐carbonized fillers were obtained by pyrolysis of wood sawdust activated by Ni, Co, or Fe salts. X‐ray diffraction showed that the fillers were of nanometric size. Thermogravimetric analysis was executed to investigate the thermal strength of the materials as well as to calculate the metal content in the carbon‐based fillers. The onset degradation temperature showed an enhancement of 17°C, whereas the maximum degradation temperatures increased 4°C with the introduction of the filler. Differential scanning calorimetry indicated an improvement of 3°C in crystallization temperature, whereas the melting temperature remained unchanged compared to neat polyethylene. The filler was shown to increase the modulus of elasticity of the nanocomposites. The addition of 1.0 wt.% of the metal‐carbonized material in the diamagnetic polymer matrix resulted in a thermoplastic nanocomposite with ferromagnetic behavior. POLYM. ENG. SCI., 60:988–995, 2020. © 2020 Society of Plastics Engineers
Searching for Prosociality in Qualitative Data: Comparing Manual, Closed–Vocabulary, and Open–Vocabulary Methods
Authors: McAuliffe William H.B. , Moshontz Hannah , McCauley Thomas G. , McCullough Michael E.
Published: February 2020

Although most people present themselves as possessing prosocial traits, people differ in the extent to which they actually act prosocially in everyday life. Qualitative data that were not ostensibly collected to measure prosociality might contain information about prosocial dispositions that is not distorted by self–presentation concerns. This paper seeks to characterise charitable donors from qualitative data. We compared a manual approach of extracting predictors from participants’ self–described personal strivings to two automated approaches: A summation of words predefined as prosocial and a support vector machine classifier. Although variables extracted by the support vector machine predicted donation behaviour well in the training sample ( N = 984), virtually, no variables from any method significantly predicted donations in a holdout sample ( N = 496). Raters’ attempts to predict donations to charity based on reading participants’ personal strivings were also unsuccessful. However, raters’ predictions were associated with past charitable involvement. In sum, predictors derived from personal strivings did not robustly explain variation in charitable behaviour, but personal strivings may nevertheless contain some information about trait prosociality. The sparseness of personal strivings data, rather than the irrelevance of open–ended text or individual differences in goal pursuit, likely explains their limited value in predicting prosocial behaviour. © 2020 European Association of Personality Psychology
Effects of developmental relationships with teachers on middle‐school students’ motivation and performance
Authors: Scales Peter C. , Van Boekel Martin , Pekel Kent , Syvertsen Amy K. , Roehlkepartain Eugene C.
Published: February 2020

We examined how middle‐school students’ motivation, belonging, school climate, and grade point average (GPA) are affected by students experiencing developmental relationships—those that go beyond teachers being caring (e.g., showing warmth to students) and providing challenge (e.g., high expectations) to also include teachers providing support, sharing power, and expanding students’ sense of possibilities. We also examined variations in those associations by student socioeconomic status (SES). The study included 534 diverse Grades 6–8 students (51% female, 46% non‐White, 33% eligible for free and reduced price meals). Structural equation modeling and regressions showed that students with better developmental relationships with their teachers had better outcomes. Developmental relationships strongly predicted academic motivation at both the beginning and end of the school year, and also directly predicted students’ sense of belonging and school climate. Relationships indirectly predicted GPA, through motivation. Student–teacher relationship quality for low‐SES students was lower and declined more than for other students. The results both reflect current literature in showing the importance of strong student–teacher relationships, and extend it in showing the worsening relationships quality for low‐income students, and in suggesting that strengthening multiple facets of student–teacher developmental relationships may have important effects on motivation and achievement of middle‐school students.
Body image in older breast cancer survivors: A systematic review
Authors: Davis Caitlin , Tami Perrine , Ramsay Diane , Melanson Lydia , MacLean Leah , Nersesian Sarah , Ramjeesingh Ravi
Published: February 2020

Objective

Breast cancer is the most common cancer among women world‐wide. In North America survival rates are >80%, resulting in a large population of survivors. The goal of this review was to systematically explore the literature to identify the status of body image and factors that can impact the body image of older breast cancer survivors.

Methods

A systematic review of the literature was conducted and registered with PROSPERO (CRD42019133617). EMBASE and PubMed were searched for articles including terms related to “body image” and “breast cancer.” Duplicates were removed and the remaining 322 abstracts were screened. Articles published before 2000, were off‐topic, or those that were non‐primary research articles were excluded. Sixty‐nine remaining full‐length articles were screened for language, gender and location. Seven articles underwent quality assessment of which five passed and were reviewed in depth. The remaining two articles were briefly discussed.

Results

The literature review suggests that body image is considered important in older BCS and that body image may impact or be impacted by several factors including age, menopausal status, mental health, treatment modality and exercise. Additionally, themes of dealing with physical changes and the length of time women are impacted following treatment were explored.

Conclusion

Our findings highlight that older women may be at an advantage in terms of being post‐menopausal, however concerns surrounding physical and emotional changes affecting body image are indeed present. Future studies on breast cancer survivorship should consider the inclusion of body image as an outcome measure in addition to including individuals representing a wide range of ages.
The Performance of Red Flare Pyrotechnic Compositions Modified with Gas Generating Additives
Authors: Juknelevicius Dominykas , Alenfelt Per , Ramanavicius Arunas
Published: February 2020

In this work, an effective, but still not well‐explored area of red flare pyrotechnic formulations was investigated. High magnesium content (40–60 % w.t.) and the presence of conventional gas generating materials were the specific features of formulations explored herein. Such illuminant compositions possessed a low burning rate and high specific luminous intensity. The investigated system was based on strontium nitrate, rounded magnesium powder, chlorinated rubber, binder and gas generating additives. Emission spectra, light intensity and burning time have been measured during the experiment and recalculated to the specific luminous intensity and color purity. Additives in the form of 2‐cyanoguanidine, Melamine, Azodicarbonamide, Calcium resinate, Shellac, Strontium oxalate, Lactose, Dextrin, Phenolic resin, Lignin sulfonate, 5‐aminotetrazole, Urea, Guanidinium nitrate (GN), Hexamine and Sulfur were evaluated in Mg‐rich flare compositions. The use of GN was studied more carefully as an exceptionally efficient additive that increased the flares light intensity by 60 %, in comparison to the standard GN‐free composition, while maintaining high color purity of 90–97 %.
The effect of flaxseed supplementation on circulating adiponectin and leptin concentration in adults: A systematic review and meta‐analysis of randomized controlled trials
Authors: Jalili Cyrus , Pezeshki Mehran , Askarpour Moein , Marx Wolfgang , Hassani Bahar , Hadi Amir , Ghaedi Ehsan
Published: February 2020

Objective

Our objective was to perform a systematic review and meta‐analysis on randomized controlled trials (RCTs) assessing the effect of flaxseed supplementation on serum adiponectin and leptin concentration.

Methods

Electronic searches were performed in PubMed, Scopus, Web of Science, and Google Scholar up to May 2019 without any restriction. All RCTs that reported the effect of flaxseed supplementation on circulating adiponectin and leptin concentration were included. A random‐effects model was used to pool calculated effect sizes.

Results

Nine RCTs (11 arms) were eligible to be included. Our analysis showed that flaxseed supplementation did not significantly affect adiponectin (weighted mean difference [WMD]: 0.15 μg/ml; 95% CI [−0.16, 0.47], p = .34) and leptin (WMD: 0.47 ng/ml; 95% CI [−3.10, 4.06], p = .79) concentration in comparison with control. Furthermore, subgroup analysis revealed that effects remained nonsignificant in all subgroups of trial duration, flaxseed type, and health status of participants. The pooled effect size was also robust and remained nonsignificant in the sensitivity analysis.

Conclusion

Flaxseed supplementation had no significant effect on adiponectin and leptin levels in adults. However, future well‐designed trials are still needed to confirm these results.
Nitrogen mineralization from organic materials and fertilizers: Predicting N release
Authors: Cassity‐Duffey Kate , Cabrera Miguel , Gaskin Julia , Franklin Dory , Kissel David , Saha Uttam
Published: February 2020

Organic growers use a wide range of organic fertilizers and materials to supply nutrients and meet plant demand of N. These products range from commercially processed animal and plant byproducts to composts and poultry litters. To better synchronize N release with plant demand, we investigated the rate and pool of potentially mineralizable N from 22 commercial, organic fertilizers; 15 poultry litters; and 11 composts. Fertilizers and organic materials were mixed with soil and inorganic N was measured over 99 days under optimal conditions (50% estimated water holding capacity and 30°C). Net N mineralized from the organic fertilizer or material was determined and fit to first‐order kinetics to determine the rate of mineralization (k) and the pool of mineralizable nitrogen (N0). Net N mineralized ranged from 25–93%, 10–55%, and 1–5% of the organic N applied for the fertilizers, poultry litters, and composts that mineralized, respectively. The pool of mineralizable N was accurately predicted from the initial total N of the materials, but no characteristics predicted the rate constant,k. Using a grouped approach based on product type and the percentage of N mineralized to determinek, we were able to predict net mineralized for fertilizers (R2 = 0.84) and poultry litters (R2 = 0.62).
Adaptive multiarm multistage clinical trials
Authors: Ghosh Pranab , Liu Lingyun , Mehta Cyrus
Published: February 2020

Two methods for designing adaptive multiarm multistage (MAMS) clinical trials, originating from conceptually different group sequential frameworks are presented, and their operating characteristics are compared. In both methods pairwise comparisons are made, stage‐by‐stage, between each treatment arm and a common control arm with the goal of identifying active treatments and dropping inactive ones. At any stage one may alter the future course of the trial through adaptive changes to the prespecified decision rules for treatment selection and sample size reestimation, and notwithstanding such changes, both methods guarantee strong control of the family‐wise error rate. The stage‐wise MAMS approach was historically the first to be developed and remains the standard method for designing inferentially seamless phase 2‐3 clinical trials. In this approach, at each stage, the data from each treatment comparison are summarized by a single multiplicity adjusted P‐value. These stage‐wise P‐values are combined by a prespecified combination function and the resultant test statistic is monitored with respect to the classical two‐arm group sequential efficacy boundaries. The cumulative MAMS approach is a more recent development in which a separate test statistic is constructed for each treatment comparison from the cumulative data at each stage. These statistics are then monitored with respect to multiplicity adjusted group sequential efficacy boundaries. We compared the powers of the two methods for designs with two and three active treatment arms, under commonly utilized decision rules for treatment selection, sample size reestimation and early stopping. In our investigations, which were carried out over a reasonably exhaustive exploration of the parameter space, the cumulative MAMS designs were more powerful than the stage‐wise MAMS designs, except for the homogeneous case of equal treatment effects, where a small power advantage was discernable for the stage‐wise MAMS designs.
Cesium‐Exchanged Lacunar Keggin Heteropolyacid Salts: Efficient Solid Catalysts for the Green Oxidation of Terpenic Alcohols with Hydrogen Peroxide
Authors: Batalha Daniel Carreira , Ferreira Sukarno Olavo , da Silva Rene Chagas , da Silva Márcio José
Published: February 2020

In this work, an innovative and green oxidative process to convert renewable and abundant raw material to more value‐added fine chemicals was developed. Hydrogen peroxide, an environmentally benign oxidant, was used in Cs–exchanged lacunar Keggin heteropolyacid salts‐catalyzed oxidation reactions of the terpenic alcohols (i. e., nerol was the model molecule). The activity of most outstanding catalyst (Cs8SiW11O39) was compared with various catalysts. Epoxides and aldehydes, which are an attractive feedstock for fragrance and pharmaceutical industries were selectively obtained. Lacunar Keggin heteropolyacid salts containing cesium as the counter ion (i. e., Cs7PW11O39, Cs7PMo11O39 and Cs8SiW11O39) were easily synthesized and characterized by infrared spectroscopy, powdered X‐rays diffraction, X‐rays dispersive spectroscopy, scanning electronic microscopy, thermal analysis, porosimetry analyses, diameter and pores distribution. The influences of the main reaction variables such as catalyst concentration, the stoichiometry of the reactants and reaction temperature were evaluated. The reaction scope was successfully extended to the other terpenic alcohols. The Cs8SiW11O39 was the most active and selective lacunar salt. After five cycles of successive reuse, no loss of catalytic activity or selectivity was observed.
A Rare Triterpenoidal Saponin Isolated and Identified fromTetraena simplex(L.) Beier &Thulin (Syn.Zygophyllum simplexL.)
Authors: Baky Mostafa H. , Gabr Nagwan M. , Shawky Enas M. , Elgindi Mohamed R. , Mekky Reham H.
Published: February 2020

Tetraena simplex(L.) Beier & Thulin (syn.Zygophyllum simplexL.) is an annual, succulent plant belonging to family Zygophyllaceae. The plant grows in harsh environmental conditions and it is traditionally used as an analgesic and anti‐inflammatory agent. This study aims to isolate and identify phytochemical constituents of then‐butanol fraction of its aerial parts that was repeatedly chromatographed on Diaion HP‐20 and silica gel columns to yield a rare triterpenoidal saponin, 3‐O‐[β‐D‐glucopyranosyl‐(1→2)‐β‐D‐glucopyranosyl] quinovic acid‐28‐O‐β‐D‐glucopyranosyl ester (1) along with three other known triterpenoidal compounds namely; 3‐O‐methoxy‐quinovic acid (2), quinovic acid (3), and 3‐O‐β‐D‐glucopyranosyl‐quinovic acid (4). Moreover, quercetin 3‐O‐α‐L‐rhamnoside (5) was isolated from this fraction. Different spectroscopic techniques including one dimensional (1D) and two dimensional (2D) NMR (Nuclear Magnetic Resonance) spectroscopy allowed the unambiguous structure elucidation of the isolated compounds.
Ascorbyl‐6‐O‐oleate: A Bioconjugate Antioxidant Lipid
Authors: Perini Ilaria , Ambrosi Moira , Tanini Damiano , Ninham Barry W. , Capperucci Antonella , Nostro Pierandrea Lo
Published: February 2020

Ascorbyl‐6‐O‐oleate (Asc‐OL) was synthesized enzimatically and studied in the pure state and in aqueous dispersions. Small‐angle X‐ray scattering (SAXS), differential scanning calorimetry (DSC), Fourier transformed infrared (FTIR) spectroscopy experiments and antioxidant tests were conducted in order to characterize the compound and to evaluate its reducing properties. Asc‐OL is a bioconjugate molecule, in fact it combines the main physico‐chemical features of the two parent molecules, i. e. the redox and acidic properties of Vitamin C and the fluid‐like state of oleic acid. The appropriate tests were carried out to confirm the excellent radical scavenging activities of Asc‐OL, that turned out to be a promising candidate for the stabilization, transport and protection against radical attack of valuable hydrophobic active ingredients used in food and pharmaceutical formulations.
Metal‐Ceramic Composites for Photocatalytic Oxidation of Diclofenac in Aqueous Solution
Authors: Sherstoboeva Maria V. , Bavykina Anastasiya V. , Bolgaru Konstantin A. , Maksimov Yury M. , Sastre Francesc , Skvortsova Lidia N.
Published: February 2020

Photocatalytic activity of metal‐ceramic composites synthesized by self‐propagating high‐temperature synthesis (SHS) is investigated in the processes of degradation of diclofenac (DCF). Optical properties of the composites were studied, and the band gaps of ceramic matrix semiconducting components were calculated from the absorbance spectra. The effect of the phase composition, UV irradiation duration, the nature and quantity of the activator (H2C2O4 and H2O2) on the degree of oxidation destruction was investigated. The best catalytic performance (98–99 % DCF degradation) was achieved with the combination of heterogeneous boron nitride and SiAlON based composites and a homogeneous photo‐Fenton system. However, DCF decomposition with a minimum number of intermediates was achieved using boron nitride‐based composites.
Phosphate and Water Sensing with a Zinc‐Dipicolylamine‐Based Charge‐Transfer Dye
Authors: Gayton Jacqueline , Autry Shane A. , Kolodziejczyk Wojciech , Hill Glake A. , Hammer Nathan I. , Delcamp Jared H.
Published: February 2020

A D‐π‐A (donor‐π bridge‐acceptor) dye with a conjugated dipicolylamine group as the donor was synthesized and characterized. When zinc is bound to the dipicolylamine ligand, charge transfer strength from the donor is decreased resulting in a large blue‐shift in the absorption spectrum with a quenching of dye emission. Upon addition of phosphate, changes in both the absorption and emission spectrum are observed with intermediate states between the starting zinc complex and free dye observed. The zinc‐dye complex was found to react with two equivalents of phosphate or trace water to give the free dye. The water response is unexpected given the widespread use of the dipicolylamine group as an anion sensor in water. When the dipicolylamine group is part of conjugated D‐π‐A dye designs with zinc complexes, the dye is observed to act as a humidity sensor at low water amounts.
Construction of Defect‐Rich Ni‐Fe‐Doped K0.23MnO2 Cubic Nanoflowers via Etching Prussian Blue Analogue for Efficient Overall Water Splitting
Authors: Liao Huanyun , Guo Xingzhong , Hou Yang , Liang Hao , Zhou Zheng , Yang Hui
Published: February 2020

Designing elaborate nanostructures and engineering defects have been promising approaches to fabricate cost‐efficient electrocatalysts toward overall water splitting. In this work, a controllable Prussian‐blue‐analogue‐sacrificed strategy followed by an annealing process to harvest defect‐rich Ni‐Fe‐doped K0.23MnO2 cubic nanoflowers (Ni‐Fe‐K0.23MnO2 CNFs‐300) as highly active bifunctional catalysts for oxygen and hydrogen evolution reactions (OER and HER) is reported. Benefiting from many merits, including unique morphology, abundant defects, and doping effect, Ni‐Fe‐K0.23MnO2 CNFs‐300 shows the best electrocatalytic performances among currently reported Mn oxide‐based electrocatalysts. This catalyst affords low overpotentials of 270 (320) mV at 10 (100) mA cm−2 for OER with a small Tafel slope of 42.3 mV dec−1, while requiring overpotentials of 116 and 243 mV to attain 10 and 100 mA cm−2 for HER respectively. Moreover, Ni‐Fe‐K0.23MnO2 CNFs‐300 applied to overall water splitting exhibits a low cell voltage of 1.62 V at 10 mA cm−2 and excellent durability, even superior to the Pt/C||IrO2 cell at large current density. Density functional theory calculations further confirm that doping Ni and Fe into the crystal lattice of δ‐MnO2 can not only reinforce the conductivity but also reduces the adsorption free‐energy barriers on the active sites during OER and HER.
Lightning attachment behavior of wind turbine generator with blades equipped with two lightning receptors
Authors: Wang Jianguo , Wang Yu , Zhou Mi , Liu Yuhe , Li Jin , Su Rui , Xue Jian
Published: February 2020

Lightning striking of wind turbine generators (WTGs) has taken place frequently in recent years and usually results in severe blade damages. In order to study the lightning attachment behavior of the WTG, a scaled‐down model with a ratio of 1:100 was assembled to simulate a 2 MW‐class wind turbine for which each blade is equipped with two pairs of lightning receptors. In order to simulate the lightning strikes from different directions, the high‐voltage rod electrode was repositioned at 29 orientations with respect to the WTG model, and by energizing the rod electrode via an impulse voltage generator, which can generate the switching impulse voltage and the lightning impulse voltage, the negative and positive impulses were generated. Obtained results show that the negative impulses tend to be intercepted by the blade‐tip receptor, whereas the positive ones are also likely to attach to the insulation parts of blade and the nacelle. Moreover, the switching impulse is prone to being intercepted by the insulation parts of blade, more distinctly than that in the case of lightning impulse. The interception efficiency of the WTG model, represented by the ratio of number of discharges intercepted by blade receptors and lightning rod against the total applied strikes, is larger in the case of negative impulse than that of the positive impulse. Our test results show important implications for the phenomenon of lightning damage and the attachment behavior of WTGs affected by lightning polarity and waveform. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Financing the circular economic model
Authors: Aboulamer Anas , Soufani Khaled , Esposito Mark
Published: February 2020

Capitalism, as we know it, is the result of the industrial revolution, when resources were perceived as abundant and limitless. The population was much smaller and the environmental impact of the industrial activity was perceived as minimal. As the world population increased exponentially and more countries emerged from poverty to join the middle‐income rank, demand for products increased leading to a rapid industrialization with no concerns for its environmental and societal impact. Capitalism is also based on the idea of free markets that adjust automatically to new information about scarcity, demand, and processes of production to allocate resources in the most efficient way possible. However, free market implies that possibly unobservable factors are taken into consideration to lower the potential impact of negative externalities by imbedding them in the pricing process. Unfortunately, free markets failed in this task and the list of environmental disasters from the Gulf oil spill of BP, the tobacco health issue are good examples of the inability of the markets to gauge the impact of these negative externalities.
Cover Image, Volume 12, Issue 2
Authors: Wege Christina , Koch Claudia
Published: February 2020

The cover image is based on the Advanced Review From stars to stripes: RNA‐directed shaping of plant viral protein templates ‐ structural synthetic virology for smart biohybrid nanostructures, by Christina Wege and Claudia Koch. https://doi.org/10.1002/wnan.1591.

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Determining elemental strontium distribution in rat bones treated with strontium ranelate and strontium citrate using 2D micro‐XRF and 3D dual energy K‐edge subtraction synchrotron imaging
Authors: Cardenas Daniel , Turyanskaya Anna , Rauwolf Mirjam , Panahifar Arash , Cooper David , Wohl Gregory R. , Streli Christina , Wobrauschek Peter , Pejović‐Milić Ana
Published: February 2020

Strontium‐based medications, such as strontium ranelate, have been suggested to have therapeutic effects in patients with osteoporosis. Strontium salts available off‐shelf in stores across North America are assumed to provide similar effects as strontium ranelate and thus should lead to similar distributions of elemental strontium incorporated in bone. The objective of this study was to compare the spatial distribution of strontium in animal bones following the administration of strontium ranelate and strontium citrate. Seventeen‐week‐old Sprague–Dawley rats were split into three groups over 10 weeks and given 625 mg/kg/day of strontium ranelate and 676 mg/kg/day of strontium citrate; the control group received no additional supplementary strontium. The humeri were collected from all animals, and strontium distribution was mapped using 2D micro‐XRF and 3D dual energy K‐edge subtraction (KES) imaging. 2D and 3D elemental mapping methods demonstrated that strontium delivered during treatment by both salts had the same spatial distribution. 3D elemental strontium maps of treated animal bones showed that strontium was largely observed in the trabecular regions under the epiphyseal (growth) plate. The thickness of the strontium layers in both the strontium ranelate and strontium citrate sample was not significantly different (p = .9201). 2D micro‐XRF and 3D dual‐energy KES images effectively elucidated the spatial distribution of elemental strontium in calcified tissue. These methods provide a novel approach to evaluating the potential efficacy of strontium supplements in the treatment of osteoporosis.
Physiological functions of SPP/SPPL intramembrane proteases
Authors: Mentrup Torben , Cabrera-Cabrera Florencia , Fluhrer Regina , Schröder Bernd
Published: February 2020

Intramembrane proteolysis describes the cleavage of substrate proteins within their hydrophobic transmembrane segments. Several families of intramembrane proteases have been identified including the aspartyl proteases Signal peptide peptidase (SPP) and its homologues, the SPP-like (SPPL) proteases SPPL2a, SPPL2b, SPPL2c and SPPL3. As presenilin homologues, they employ a similar catalytic mechanism as the well-studied γ-secretase. However, SPP/SPPL proteases cleave transmembrane proteins with a type II topology. The characterisation of SPP/SPPL-deficient mouse models has highlighted a still growing spectrum of biological functions and also promoted the substrate discovery of these proteases. In this review, we will summarise the current hypotheses how phenotypes of these mouse models are linked to the molecular function of the enzymes. At the cellular level, SPP/SPPL-mediated cleavage events rather provide specific regulatory switches than unspecific bulk proteolysis. By this means, a plethora of different cell biological pathways is influenced including signal transduction, membrane trafficking and protein glycosylation.
Effective Mass of the Polaron—Revisited
Authors: Dybalski Wojciech , Spohn Herbert
Published: February 2020

Properties of the energy–momentum relation for the Fröhlich polaron are of continuing interest, especially for large values of the coupling constant. By combining spectral theory with the available results on the central limit theorem for the polaron path measure, we prove that, except for an intermediate range of couplings, the inverse effective mass is strictly positive and coincides with the diffusion constant. Such a result is established also for polaron-type models with a suitable ultraviolet cut-off and for arbitrary values of the coupling constant. We point out a slightly stronger variant of the central limit theorem which would imply that the energy–momentum relation has auniqueglobal minimum attained at zero momentum.
Flowering patterns change along elevational gradients and relate to life-history strategies in 29 herbaceous species
Authors: Bucher Solveig Franziska , Römermann Christine
Published: February 2020

Patterns of flowering phenology, i.e. first and last flowering day (FFD and LFD) and flowering duration (FD) govern plant pollination and reproduction. Most research has focused on FFD whereas LFD, FD and second flowering events were neglected although they are crucial events. To assess whether flowering patterns change species-specifically with changing abiotic conditions and whether these are related to leaf persistence, reproduction and pollination syndrome, we monitored flowering phenology (including also second flowering events) of 29 herbaceous species along two elevational gradients ranging from 700 to 1800 m a.s.l. in two consecutive years. FFD was delayed with increasing elevation. LFD followed two alternative strategies: species which ceased flowering early in the season delayed LFD with increasing elevation, species which ceased flowering late did not change LFD. FD decreased with increasing elevation in most species. The timing of flowering phenology had strong influences on the intensity of change along the elevational gradient and other stages of flowering phenology. Many species showed a second flowering event which occurred irrespective of elevation, suggesting a link to unsuccessful pollination rather than temperature. Life history strategies helped explain patterns of flowering phenology and a species’ ability to track changes in abiotic conditions, e.g. evergreen species started to flower earlier than summer green species and insect-pollinated species were able to expand FD most. These findings give insight into species-specific changes in phenological patterns and thus plant performance with changing environment. They should be considered when assessing the consequences of environmental change at both the community and ecosystem level.
Idiopathische Chondrolyse beider Hüftgelenke – Fallbericht bei einer adoleszenten Patientin
Authors: Schumann Eckehard , Kübler Fabian Bastian , Roth Christian , Heyde Christoph‑E. , Roth Andreas
Published: February 2020

Am Fallbeispiel eines 12-jährigen Mädchens wird die Diagnose und Therapie einer idiopathischen Chondrolyse der Hüftgelenke beschrieben. Die Patientin stellte sich mit intermittierenden Schmerzen und hochgradigen Funktionsstörungen beider Hüften vor. Nach klinischer Untersuchung und Beckenübersichtsröntgenaufnahme zeigte die MRT die typischen Veränderungen einer idiopathischen Chondrolyse. Die rein konservative Therapie mit einer konsequenten physiotherapeutischen Behandlung und regelmäßigen Einnahme eines nichtsteroidalen Antirheumatikums hat ein gutes klinisches Ergebnis erbracht.
Geometry of holomorphic mappings and Hölder continuity of the pluricomplex Green function
Authors: Pierzchała Rafał
Published: February 2020

We provide a solution to a long-standing open problem that lives in the interface of pluripotential theory and multivariate approximation theory. The problem is to characterize the holomorphic maps which preserve Hölder continuity of the pluricomplex Green function associated with a compact subset of$${\mathbb {C}}^N$$CN. We also prove, under mild restrictions, that nondegenerate holomorphic maps preserve Markov’s inequality for polynomials.
A filtered Boris algorithm for charged-particle dynamics in a strong magnetic field
Authors: Hairer Ernst , Lubich Christian , Wang Bin
Published: February 2020

A modification of the standard Boris algorithm, called filtered Boris algorithm, is proposed for the numerical integration of the equations of motion of charged particles in a strong non-uniform magnetic field in the asymptotic scaling known as maximal ordering. With an appropriate choice of filters, second-order error bounds in the position and in the parallel velocity, and first-order error bounds in the normal velocity are obtained with respect to the scaling parameter. This also yields a second-order approximation to the guiding center motion. The proof compares the modulated Fourier expansions of the exact and the numerical solutions. Numerical experiments illustrate the error behaviour of the filtered Boris algorithm.