bluuebunny/crossref_metadata_2025 huggingface dataset:
Misuse of Habitat Terminology by Wildlife Educators, Scientists, and Organizations
Authors: Darracq Andrea K. , Tandy Jordan
Published: May 2019

We analyzed the use of habitat terminology in articles from the Journal of Wildlife Management (JWM) each year (1998–2017) in course descriptions from 1 wildlife biology degree program in each state within the United States, and by wildlife‐related non‐profit organizations and state and federal agencies. Sixty‐five percent of JWM articles fluctuated in their correct use and 31% incorrectly used the term habitat and there was no significant decrease in the misuse of the term since 1998. Habitat type was used in 46% of the papers analyzed and was always used incorrectly. Misuse of the term habitat type in JWM articles decreased since 1998, from 70% of articles using the term from 1998 to 2002, 50% from 2013 to 2016, and no papers using the term in 2017. From the course descriptions using the term habitat, 75% fluctuated in their correct use and 13% incorrectly used habitat terminology. When considering only the management course descriptions and the term wildlife habitat as correct, 28% of programs fluctuated in their correct use and 31% incorrectly used habitat terminology. All wildlife‐related organizations fluctuated in their correct use of the term habitat. Our results demonstrate that the misuse of habitat terminology is still being missed during the JWM editorial process, at least until very recently. In combination with the continued misuse of habitat terminology in the primary literature, our results suggest an underlying reason for the continued incorrect use of habitat terminology is the misuse of the terms by educators within wildlife degree programs and by wildlife‐related organizations. By dealing with misuse of habitat terminology at the undergraduate level concurrent with misuse in the primary literature and by wildlife‐related organizations, we should begin to see a shift in the correct use of habitat terminology in current and future generations of natural resource professionals. © 2019 The Wildlife Society.
Land use and dispersal influence mortality in white‐tailed deer
Authors: Haus Jacob M. , Webb Stephen L. , Strickland Bronson K. , Rogerson Joseph E. , Bowman Jacob L.
Published: May 2019

Restoring male age structure in white‐tailed deer populations has become an important objective for many state agencies aimed at improving herd dynamics. Limiting mortality in the yearling (1–2 yr old) age class is a primary consideration, and regional differences in climate, habitat characteristics, hunting regulations, and hunter behavior complicate the understanding of how specific factors influence the risk of mortality. We used Cox proportional hazard modeling to determine the effects of body size, mean distance to road, dispersal behaviors, use of forested land, and use of land open to public hunting on the risk of mortality for a population of radio‐collared, yearling males (n= 76) in Sussex County, Delaware, USA. Annual survival averaged 0.55 (95% CI = 0.45–0.68), with harvest accounting for 79% (26/33) of all mortalities. Measurements of body size (chest girth, shoulder height, and total length; cm) influenced dispersal probability but not dispersal distance. The best approximating model for mortality risk included a covariate for landownership, whereby mortality risk increased on public land. Among males who dispersed, longer‐distance dispersal was associated with reduced mortality, which contradicts previous research describing dispersal as a high‐risk behavior. The effect of landownership on mortality risk has not been previously identified, especially when regulations regarding harvest of yearling males are similar between landownership types. We observed annual survival rates of 0.69 (95% CI = 0.57–0.82) for deer apparently using private land exclusively during the hunting season, and 0.20 (95% CI = 0.11–0.48) for deer that used public land during the hunting season. Survival rates on private land were comparable to those of other regions actively managing male age structure. These results suggest survival of yearling males in the region is influenced by hunter harvest and the risks associated with dispersal may be minimal in areas where harvest pressure is low, although hunter harvest on public land may limit male age structure on a localized scale. © The Wildlife Society, 2019
Columbian sharp‐tailed grouse nesting ecology: wind energy and habitat
Authors: Proett Matt , Roberts Shane B. , Horne Jon S. , Koons David N. , Messmer Terry A.
Published: May 2019

The rapid pace of wind‐energy development has increased stakeholder concerns regarding the potential effects on wildlife. Locations targeted for wind‐energy development frequently overlap prairie grouse and greater sage‐grouse (Centrocercus urophasianus) habitats. Research suggests that anthropogenic developments may have negative effects on these species. There is, however, no information published regarding the effect of wind‐energy development on Columbian sharp‐tailed grouse (Tympanuchus phasianellus columbianus), a subspecies that has twice been petitioned for Endangered Species Act protection. To address this need, from 2014 to 2015 we studied Columbian sharp‐tailed grouse nesting ecology across restored grasslands in eastern Idaho, USA, where a 215‐turbine wind‐energy complex had been developed. We monitored 147 nests from 135 females captured at leks 0.1–13.8 km from wind turbines. We used an information‐theoretic approach to evaluate the influence of wind‐energy infrastructure and habitat characteristics on nest‐site selection and daily nest survival. We did not detect any influence of wind‐energy infrastructure on nest‐site selection or nest survival. Nest‐site selection and daily nest survival were influenced by vegetation structure and composition measured at 2 spatial scales. Females selected nest sites with more restored grassland containing >30% forb cover within the nesting core‐use area (i.e., 60 ha around the nest) and exhibited a functional response to the availability of that land cover type. Daily nest survival was best predicted by visual obstruction at the nest site and the amount of restored grassland containing >30% forb cover within the nesting core‐use area. We recommend wildlife managers continue to implement management practices that will provide bunchgrass‐dominated grasslands with >30% forb cover in restored grasslands (e.g., Conservation Reserve Program fields) within Columbian sharp‐tailed grouse range. © The Wildlife Society, 2019
Is it common for charge recombination to be faster than charge separation?
Authors: Espinoza Eli M. , Bao Duoduo , Krzeszewski Maciej , Gryko Daniel T. , Vullev Valentine I.
Published: May 2019

Attaining long‐lived charge‐transfer (CT) states is of the utmost importance for energy science, photocatalysis, and materials engineering. When charge separation (CS) is slower than consequent charge recombination (CR), formation of a CT state is not apparent, yet the CT process provides parallel pathways for deactivation of electronically excited systems. The nuclear, or Franck‐Condon (FC), contributions to the CT kinetics, as implemented by various formalisms based on the Marcus transition‐state theory, provide an excellent platform for designing systems that produce long‐lived CT states. Such approaches, however, tend to underestimate the complexity of alternative parameters that govern CT kinetics. Here we show a comparative analysis of two systems that have quite similar FC CT characteristics but manifest distinctly different CT kinetics. A decrease in the donor‐acceptor electronic coupling during the charge‐separation step provides an alternative route for slowing down undesired charge recombination. These examples suggest that, while infrequently reported and discussed, cases where CR is faster than CS are not necessarily rare occurrences.
Episodic hypoxia in the western basin of Lake Erie
Authors: Jabbari Aidin , Ackerman Josef D. , Boegman Leon , Zhao Yingming
Published: May 2019

Hypoxic conditions continue to be an environmental concern in lakes, including those with shallow and well‐mixed basins, such as the western basin of Lake Erie, in which hypoxia is not anticipated. We investigated the dynamics and causes of hypoxia using field measurements at two locations in the western basin during the late summer of 2017. Two hypoxic events (dissolved oxygen [DO] concentrations < 2 mg L−1) were recorded that were caused by upwelling of hypolimnetic water from the central basin of the lake following winds from the south and southwest. In this case, instantaneous stratification occurred when cool central basin water (i.e., 15.7°C) intruded as a 2.5‐m‐thick layer above the bottom under the warm western basin waters (i.e., 23.9°C). A third hypoxic event, which was associated with more typical thermal stratification from atmospheric warming, occurred during a calm and warm period near the end of the deployment. In this case, we observed a continuous decline in hypolimnetic DO from ≈ 8 to < 5 mg L−1, which likely declined to < 2 mg L−1 in 14 d using a one‐dimensional model. Interbasin exchange flows generated instantaneous hypoxia multiple times within a year and were the dominate cause (63% of 11 cases) of hypoxia identified during August fishing trawls in the study area over the past 30 yr. Results of this work should help with the prediction and understanding of hypoxia in lakes with multiple basins, which will be informative for water quality and fisheries management.
A µ‐XANES study of the combined oxidation/sulfidation of Fe–Cr model alloys
Authors: Weber Kathrin , Guilherme Buzanich Ana , Radtke Martin , Reinholz Uwe , Stephan‐Scherb Christiane
Published: May 2019

The precise analysis of cation diffusion profiles through corrosion scales is an important aspect to evaluate corrosion phenomena under multicomponent chemical load, as during high‐temperature corrosion under deposits and salts. The present study shows a comprehensive analysis of cation diffusion profiles by electron microprobe analysis and microbeam X‐ray absorption near edge structure (µ‐XANES) spectroscopy in mixed oxide/sulfide scales grown on Fe–Cr model alloys after exposing them to 0.5% SO2. The results presented here correspond to depth‐dependent phase identification of oxides and sulfides in the corrosion scales by µ‐XANES and the description of oxidation‐state‐dependent diffusion profiles. Scales grown on low‐ and high‐alloyed materials show both a well‐pronounced diffusion profile with a high concentration of Fe3+ at the gas and a high concentration of Fe2+ at the alloy interface. The distribution of the cations within a close‐packed oxide lattice is strongly influencing the lattice diffusion phenomena due to their different oxidation states and therefore different crystal‐field preference energies. This issue is discussed based on the results obtained by µ‐XANES analysis.
Synthesis of Diblock and Triblock Polymers from Cyclooctadiene and Norbornene Via ROMP in Miniemulsion
Authors: Torres‐Rocha Olga Lidia , Wu Xiaowei , Zhu Chunyang , Crudden Cathleen M. , Cunningham Michael F.
Published: May 2019

The synthesis of diblock and triblock linear polyolefins via ring opening metathesis polymerization (ROMP) in an aqueous nanoparticle dispersion is presented. The different block polyolefins are synthesized from the cyclic olefins 1,5‐cyclooctadiene and norbornene (NB), using a water‐soluble TEGylated ruthenium alkylidene catalyst, yielding the structures PCOD‐b‐PNB, PNB‐b‐PCOD, and PCOD‐b‐PNB‐b‐PCOD. High monomer conversion (>90%), monitored by NMR, is achieved in relatively short times (≈1 h) for the polymerization of each block. The livingness of the system, essential to obtain block copolymers, is confirmed by gel permeation chromatography. Latex particles' size during the multiple steps range between 90 and 150 nm. The results demonstrate that it is possible to obtain nanoparticle latexes from ROMP‐based monomers with block copolymer architectures, creating the opportunity to copolymerize olefins bearing different functional groups for the synthesis of new materials.
A One‐Pot Polymerization for Concurrently Inducing Predominant Helicity in Optically Inactive Helical Polymer and Constructing Graphene‐Based Chiral Hybrid Foams
Authors: Li Pengpeng , Ma Zongwen , Mei Song , Pan Kai , Deng Jianping
Published: May 2019

Synthetic chiral helical polymers have achieved impressive progress in past few decades. Unfortunately, how to construct chiral helical polymer‐derived functional materials still remains highly challenging. The present contribution reports an unprecedented, one‐step strategy for judiciously combining chiral helical polymer with graphene to construct chiral hybrid foams. Graphene oxide (GO), ascorbic acid (L‐AA), Rh catalyst, and an achiral acetylenic monomer bearing phenylboronic acid group are mixed in an aqueous dispersion. Under mild conditions, the monomer underwent polymerization; meanwhile GO transforms into reduced graphene oxide (RGO) which in situ self‐assembles to construct a 3D porous structure. Herein, L‐AA simultaneously plays double roles: 1) working as a chiral source for the monomer to undergo helix‐sense‐selective polymerization or transferring its chirality to the polymer chains via forming borate structure; and 2) working as a reducing agent for reducing GO. The preparation strategy combines four processes into one single step: monomer polymerization, chirality transfer, reduction of GO, and RGO's self‐assembly. The eventually obtained chiral hybrid foams demonstrate advantages of porous structure, chirality, and reversible borate functional groups. The established preparation strategy promises a potent platform for conveniently constructing advanced chiral polymeric materials and even chiral hybrids starting from achiral monomers.
Spatial and temporal dynamics of bacterioplankton community composition in a subtropical dammed karst river of southwestern China
Authors: Yu Shi , He Ruoxue , Song Ang , Huang Yadan , Jin Zhenjiang , Liang Yueming , Li Qiang , Wang Xiaohong , Müller Werner E. G. , Cao Jianhua
Published: May 2019

River damming influences the hydro‐physicochemical variations in karst water; however, such disruption in bacterioplankton communities has seldom been studied. Here, three sampling sites (city‐river section, reservoir area, and outflow area) of the Ca2+–Mg2+–HCO3−–SO42− water type in the dammed Liu River were selected to investigate the bacterioplankton community composition as identified by high‐throughput 16S rRNA gene sequencing. In the dammed Liu River, thermal regimes have been altered, which has resulted in considerable spatial‐temporal differences in total dissolved solids (TDSs), oxidation‐reduction potential (Eh), dissolved oxygen (DO), and pH and in a different microenvironment for bacterioplankton. Among the dominant bacterioplankton phyla, Proteobacteria, Actinobacteria, Bacteroidetes, and Cyanobacteria account for 38.99%–87.24%, 3.75%–36.55%, 4.77%–38.90%, and 0%–14.44% of the total reads (mean relative frequency), respectively. Bacterioplankton communities are dominated by Brevundimonas, Novosphingobium, Zymomonas, the Actinobacteria hgcIclade, the CL500‐29 marine group, Sediminibacterium, Flavobacterium, Pseudarcicella, Cloacibacterium, and Prochlorococcus. Their abundances covary with spatial‐temporal variations in hydro‐physicochemical factors, as also demonstrated by beta diversity analyses. In addition, temperature plays a pivotal role in maintaining bacterioplankton biodiversity and hydro‐physicochemical variations. This result also highlights the concept that ecological niches for aquatic bacteria in dammed karst rivers do not accidentally occur but are the result of a suite of environmental forces. In addition, bacterioplankton can alter the aquatic carbon/nitrogen cycle and contribute to karst river metabolism.
Bottom Currents Affect Spanner Crab Catch Rates in Southern Queensland, Australia
Authors: Spencer David M. , Brown Ian W. , Doubell Mark J. , McGarvey Richard , Lee Shing Y. , Lemckert Charles J.
Published: May 2019

During daily fishing operations, spanner crab Ranina ranina catch rates can fluctuate substantially, but the environmental drivers responsible for these fluctuations largely remain unresolved. Earlier research suggests that spanner crab catchability increases with strengthening currents, but uncertainties surround the magnitude of the measured current speeds and, consequently, their relationship with catch rates. Here, we explore the effects of bottom currents on spanner crab catch rates in South East Queensland, Australia. Using generalized additive mixed modeling, our results indicated that strengthening current speeds increased catch rates until reaching approximately 0.15 m/s, at which point the catch rates began to gradually decline. Results from a general linear regression model also showed that between fishing periods carried out on the same day, catch rates increased or decreased concurrently with current speeds. We conclude that bottom current speed should be considered in future stock assessment models. Better understanding the processes responsible for changes in bottom current speed will enable more accurate estimates of spanner crab population densities in the Australian fishery and will benefit the economic efficiency of commercial crabbing operations. Furthermore, future studies that investigate the effects of current speed on catch rates for other crab species should consider differences in locomotory characteristics and how they may impact the foraging efficiency of crabs under different flow conditions.
Cognitive Functional Abilities in Parkinson's Disease: Agreement Between Patients and Informants
Authors: Deck Benjamin L. , Xie Sharon X. , Choi Gyujae , Rick Jacqueline , Siderowf Andrew , Rudovsky Samuel , Chen‐Plotkin Alice , Duda John E. , Morley James F. , Dahodwala Nabila , Trojanowski John Q. , Weintraub Daniel
Published: May 2019

Background

The Penn Parkinson's Daily Activities Questionnaire‐15 (PDAQ‐15) assesses cognition‐related instrumental activities of daily living (IADL) in Parkinson's disease (PD).

Objectives

To assess the degree and predictors of disagreement between patients (PT) and knowledgeable informants (KI) on the PDAQ‐15.

Methods

We recruited 254 PT and KI pairs (PT‐KI), determined predictors of agreement, and compared scores to a performance‐based functional measure (Direct Assessment of Functional Status [DAFS]; N = 61).

Results

PT and KI total score (intraclass correlation = 0.57) and individual item (Cohen's kappa = 0.46–0.62) agreement were moderate. Patient depression, global cognition, and caregiver burden (all P < 0.05), predicted PT‐KI discrepancy. PT‐KI discrepancy was highest in patients with a dementia diagnosis, followed by mild cognitive impairment and then normal cognition (all P < 0.01), with PT rating themselves relatively more functionally intact as cognition worsened. DAFS performance was more highly correlated with KI (r = 0.82; P < 0.001) than PT (r = 0.62; P < 0.001) PDAQ‐15 score.

Conclusions

Our results support using KI as proxies when assessing cognitive IADLs in PD PTs, particularly in cases of more advanced cognitive decline.
Genetic analysis in the bariatric clinic; impact of a PTEN gene mutation
Authors: Cooiman Mellody I. , Kleinendorst Lotte , van der Zwaag Bert , Janssen Ignace M. C. , Berends Frits J. , van Haelst Mieke M.
Published: May 2019

Background

Pathogenic PTEN gene mutations are known to cause PTEN tumor hamartoma syndrome. Recent studies also suggest a role for PTEN mutations in the pathogenesis of obesity. No PTEN mutations have been reported among bariatric surgery patients and obesity treatment results are unknown. Since preventive screening for associated tumors is offered to patients with molecular proven PTEN hamartoma tumor syndrome, recognition of this condition in the bariatric surgery clinic is important.

Method

We present a patient with morbid obesity who carries a known pathogenic PTEN mutation, identified at the bariatric surgery clinic using an obesity gene panel consisting of 52 obesity–associated genes. We analyzed the weight loss response during the first 3 years after Sleeve Gastrectomy.

Results

At 1, 2 and 3 years after surgery, the patient achieved a Total Body Weight Loss of 39.4%, 48.8% and 44.9%, respectively. This corresponds to the results of a control group of 18 female patients with normal genetic test results.

Conclusion

Our patient illustrates the importance of recognizing this serious genetic condition for which preventive cancer screening options are available. The positive weight loss results after Sleeve Gastrectomy suggest that this could be a successful treatment option for obesity patients with PTEN mutations.
A case of combined 21‐hydroxylase deficiency and CHARGE syndrome featuring micropenis and cryptorchidism
Authors: Umino Satoko , Kitamura Miyuki , Katoh‐Fukui Yuko , Fukami Maki , Usui Takeshi , Yatsuga Shuichi , Koga Yasutoshi
Published: May 2019

Background

21‐hydroxylase deficiency (21‐OHD) is caused due to CYP21A2 gene variant. In males, the excess androgens produce varying degrees of penile enlargement and small testes. CHARGE syndrome (CS) has a broad spectrum of symptoms. In males, genital features such as micropenis and cryptorchidism are found in 48% of CS. There are no reports of patients with combined 21‐OHD and CS; therefore, it is unknown whether the external genitalia shows penile enlargement or micropenis with/without cryptorchidism.

Case

A boy, born at 37 weeks and 5 days of gestational age with no consanguineous marriage, was admitted to our hospital due to congenital cleft lip, cleft palate, micropenis, cryptorchidism, and a ventricular septal defect. He had severe hyponatremia and hyperkalemia on day 10. He was diagnosed to have 21‐OHD and CS. His external genitalia demonstrated both cryptorchidism and micropenis, but not penile enlargement.

Methods

DNA was extracted from peripheral leukocytes using standard procedures. Sanger sequence was performed in CYP21A2. Exome sequence was performed, and then, Sanger sequence was performed around variant in CHD7.

Results

Genetic screening for CYP21A2 gene was performed and compound heterozygous variants of c.293‐13A/C>G (IVS2‐13A/C>G) and c.518T>A (p.I172N) were detected in chromosome 6p21.3. His mother had been heterozygous variant of c.293‐13A/C>G, and his father had been heterozygous variant of c.518T>A. Simultaneously, a de novo splicing acceptor alteration in c.7165–4 A>G, in chromodomain helicase DNA binding protein‐7 (CHD7), located in chromosome 8q12 was detected, and the patient was diagnosed with 21‐OHD and CS.

Conclusion

Although these two disorders exhibit different modes of inheritance and their co‐morbidity is extremely rare, we encountered one male patient who suffered from both 21‐OHD and CS.
Characterization of EBT3 radiochromic films for dosimetry of proton beams in the presence of magnetic fields
Authors: Padilla‐Cabal Fatima , Kuess Peter , Georg Dietmar , Palmans Hugo , Fetty Lukas , Fuchs Hermann
Published: May 2019

Purpose

Radiochromic film dosimetry is extensively used for quality assurance in photon and proton beam therapy. So far, GafchromicTM EBT3 film appears as a strong candidate to be used in future magnetic resonance (MR) based therapy systems. The response of Gafchromic EBT3 films in the presence of magnetic fields has already been addressed for different MR‐linacs systems. However, a detailed evaluation of the influence of external magnetic fields on the film response and calibration curves for proton therapy has not yet been reported. This study aims to determine the dose responses of EBT3 films for clinical proton beams exposed to magnetic field strengths up to 1 T in order to investigate the feasibility of EBT3 film as an accurate dosimetric tool for a future MR particle therapy system (MRPT).

Methods

The dosimetric characteristics of EBT3 films were studied for a proton beam passing through magnetic field strengths of B = 0, 0.5, and 1 T. Absorbed dose calibration and measurements were performed using clinical proton beams in the nominal energy range of 62.4–252.6 MeV. Irradiations were done using an in‐house developed PMMA slab phantom placed in the center of a dipole research magnet. Monte Carlo (MC) simulations using the GATE/Geant4 toolkit were performed to predict the effect of magnetic fields on the energy deposited by proton beams in the phantom. Planned and measured doses from 3D box cube irradiations were compared to assess the accuracy of the dosimetric method using EBT3 films with/without the external magnetic field.

Results

Neither for the mean pixel value nor for the net optical density, any significant deviations were observed due to the presence of an external magnetic field (B ≤ 1T) for doses up to 10 Gy. Dose‐response curves for the red channel were fitted by a three‐parameter function for the field‐free case and for B = 1T, showing for both cases an R‐square coefficient of unity and almost identical fitting parameters. Independently of the magnetic field, EBT3 films showed an under‐response as high as 8% in the Bragg peak region, similarly to previously reported effects for particle therapy. No noticeable influence of the magnetic field strength was observed on the quenching effect of the EBT3 films.

Conclusions

For the first time detailed absorbed dose calibrations of EBT3 films for proton beams in magnetic field regions were performed. Results showed that EBT3 films represent an attractive solution for the dosimetry of a future MRPT system. As film response functions for protons are not affected by the magnetic field strenght, they can be used for further investigations to evaluate the dosimetric effects induced due to particle beams bending in magnetic fields regions.
Diagnostic and therapeutic musculoskeletal ultrasound applications of the shoulder
Authors: Strakowski Jeffrey A. , Visco Christopher J.
Published: May 2019

High frequency ultrasound is a valuable tool for assessing soft tissue injuries about the shoulder. It has advantages over other imaging modalities including relatively low cost, portability, and dynamic real‐time visualization. It has a high sensitivity for identifying tendon degeneration, bursitis, and rotator cuff tears. Ultrasound is also an excellent modality for diagnostic and therapeutic needle‐guided procedures. A detailed knowledge of shoulder anatomy and transducer positioning is required for obtaining adequate diagnostic value from ultrasound. This Monograph is designed to help develop scanning protocols for optimizing image acquisition for musculoskeletal assessment of the shoulder. Muscle Nerve, 2019
Rainbow Trout Migration and Use of a Nature-Like Fishway at a Great Lakes Tributary
Authors: Bunt Christopher , Jacobson Bailey
Published: May 2019

Rainbow Trout Oncorhynchus mykiss were monitored over two consecutive vernal migration periods at a nature-like fishway on the Beaver River, Ontario, to assess attraction efficiency, passage efficiency, multiple fish passage metrics, and interannual return rates from Georgian Bay, Lake Huron. Fishway evaluations have shifted to fill knowledge gaps related to the passage of nonsalmonids; however, surprisingly little work has been conducted with Rainbow Trout, with no known study assessing attraction or passage at a nature-like fishway. Attraction efficiency was 53% and passage efficiency was 100% in 2017; only two of the radio-tagged fish returned to the fishway in 2018. Upstream passage through the fishway required an average time of 152 ± 122 min. Fish spent 19–43 d upstream before returning to Lake Huron, where downstream passage required as little as 15 min. Overall, there were no significant relationships between any of the fish passage metrics and fish size or condition. These results can be used as a foundation for anadromous O. mykiss subspecies passage research and suggest that fisheries managers may need to adjust annual fishway counts. Future research should focus on developing methods to directly integrate temporal passage metrics into estimates of fishway efficiency.
Morphological aspects of crack growth in rock materials with various flaws
Authors: Lee Jooeun , Hong Jung‐Wuk
Published: May 2019

Crack evolution is initiated by the occurrence of tensile wing cracks and is then further promoted due to the crack coalescence caused by the extension of a central tensile crack segment between two relatively adjacent flaws. To understand such progressive failures in rock, a parallelized peridynamics coupled with a finite element method is utilized. Through this method, the initiation position of tensile wing cracks is observed with respect to varying inclination angles of a flaw, and then its corresponding shifting mechanism is investigated. In addition, the phenomenon of the position shifting being sensitive to various flaw shapes is discussed. Moreover, it is observed that the inclination angle of a central flaw affects the initiation position of other flaws; therefore, the initiation positions of tensile wing crack emanating from other neighboring flaws are analyzed with their angles. Following tensile wing cracks, a central tensile crack segment occurs in the bridging region between a central flaw and other neighboring flaws; the developmental patterns caused by the crack segment are discussed as well. Finally, the role a central tensile crack segment plays in the formation of crack coalescence and specimen failure is investigated in detail. The numerical results in this paper demonstrate good fidelity with established physical test results and complement them, thereby expanding the understanding of fracturing morphology in rock specimens with various flaws.
Evaluation of resistivity anisotropy parameters in the Eastern Mitidja basin, Algeria, using azimuthal electrical resistivity tomography
Authors: Aissaoui Roza , Bounif Abdallah , Zeyen Hermann , Messaoudi Sid‐Ali
Published: May 2019

We study electrical anisotropy using azimuthal electrical resistivity tomography (A‐ERT) for identifying geological layers and determining the preferential aquifer flow direction. The work presented in this paper aims at calculating the anisotropy coefficient from the inverted resistivity measurements, relating the geophysical results to the site geology and water flow direction, and comparing the results with those obtained from prior studies using hydrogeological approaches. The study area is located in the Eastern Mitidja basin, about 15 km east of Algiers. The work carried out includes three measurement points, totalling 24 ERT profiles. For each point, eight A‐ERT profiles, using Wenner–Schlumberger array configuration, were performed every 22.5° around a fixed central point. The data processing includes two‐dimensional inversion of each profile, representation of the inverted resistivities at the central points as a function of the azimuth in polar diagrams, and implementation of an inversion program to determine the best fitting azimuthal anisotropy parameters. The origin of electrical anisotropy is probably due to grain alignment, which is often observed in fine‐grained sediments such as clays and some sands. This alignment creates a higher electrical resistivity perpendicular to the alignment than parallel to it, which is an indicator for higher hydraulic permeability in the minimum resistivity direction, which corresponds to the preferential groundwater flow direction.
Are Liquid Sugars Different from Solid Sugar in Their Ability to Cause Metabolic Syndrome?
Authors: Sundborn Gerhard , Thornley Simon , Merriman Tony R. , Lang Bodo , King Christopher , Lanaspa Miguel A. , Johnson Richard J.
Published: May 2019

Objective

Intake of sugary drinks, especially soft drinks, carries increased risk for obesity and diabetes. This article reviews whether sugary drinks carry different risks for metabolic syndrome compared with foods that contain natural or added sugars.

Methods

A narrative review was performed to evaluate differences between liquid and solid sugars in their ability to induce metabolic syndrome and to discuss potential mechanisms to account for the differences.

Results

Epidemiological studies support liquid added sugars, such as soft drinks, as carrying greater risk for development of metabolic syndrome compared with solid sugar. Some studies suggest that fruit juice may also confer relatively higher risk for weight gain and insulin resistance compared with natural fruits. Experimental evidence suggests this may be due to differences in how fructose is metabolized. Fructose induces metabolic disease by reducing the energy levels in liver cells, mediated by the concentration of fructose to which the cells are exposed. The concentration relates to the quantity and speed at which fructose is ingested, absorbed, and metabolized.

Conclusions

Although reduced intake of added sugars (sucrose and high‐fructose corn syrup) remains a general recommendation, there is evidence that sugary soft drinks may provide greater health risks relative to sugar‐containing foods.
Identification of structurally diverse alkaloids in Talguenea quinquinervia (gill. Et hook) by liquid chromatography/electrospray ionisation tandem mass spectroscopy and insecticidal activity
Authors: Quiroz‐Carreño Soledad , Céspedes‐Acuña Carlos L. , Seigler David S. , Alarcón‐Enos Julio
Published: May 2019

Introduction

Talguenea quinquinervia has been used in folk medicine and to dye wool, and the main constituents are alkaloids and triterpenes. Identification of these type of compounds in this specie is a necessary step to understand the biological properties.

Objective

To evaluate the relationship between the chemical composition of root from T. quinquinervia and its insecticidal properties using liquid chromatography electrospray ionisation tandem mass spectrometry (LC‐ESI‐MS/MS).

Methods

Alkaloids were extracted using Soxhlet extraction with methanol. Total extract was partitioned at pH 2 and 12 to enrich alkaloid constituents and to remove interferences. The separation of alkaloids in the Talguenea extract was performed on a C18 column using gradient elution and their tandem mass spectra were obtained by quadrupole time‐of‐flight tandem mass spectrometry (QTOF‐MS/MS) to perform accurate mass measurements of fragment ions for the alkaloid constituents.

Results

Several types of alkaloids were separated and identified by LC‐ESI‐MS/MS. The structural assignment of individual alkaloids was performed based on convergence of MS/MS spectral data, pH partitioning behaviour, LC retention behaviour, and accurate mass measurements. The pH partition of the extract provided structural information about unknown alkaloids extracted from T. quinquinervia. A total of 20 compounds were identified and tentatively characterised, and of these 15 alkaloids were reported for the first time in the investigated T. quinquinervia.

Conclusion

The chemical profiling of alkaloids in T. quinquinervia with different origins was performed for the first time and provided diagnostic ions for diverse alkaloids in T. quinquinervia. Insecticidal activity observed can be explain by the presence of alkaloid and pentacyclic triterpenes on the fractions assayed.
Enhancing the durability of poly(lactic acid) composites by nucleated modification
Authors: Sun Ce , Li Changxin , Tan Haiyan , Zhang Yanhua
Published: May 2019

Biodegradable poly(lactic acid) (PLA) composites were prepared using an innovative combination of wood fiber (WF) and 1,3,2,4‐bis(3,4‐dimethylobenzylideno)sorbitol (DMDBS). DMDBS acted as an effective nucleating agent, which improved the mechanical properties and slowed down the degradation of the WF/PLA composites. The enzymatic degradation of the composites was examined by immersing in proteinase K or cellulase buffer. The presence of DMDBS resulted in a 26.7% increase of the crystallinity compared to the WF/PLA composites. The increase in crystallinity enhanced the thermal stability and tensile strength of the WF/DMDBS/PLA composites by 8.5%. The durability of the WF/DMDBS/PLA composites after nucleated modification was enhanced after enzymolysis. After nucleated modification, the surface of the WF/PLA composites showed clear cracks due to degradation, while these appeared about 2 weeks later in the case of the WF/DMDBS/PLA composites. The results revealed that the introduction of cellulase degraded WF in the composites, which increased hydrolysis or enzymolysis sites. The combination of nucleated modification and enzyme buffer gave an expanded downstream application of WF/PLA composites in packaging and agricultural materials. © 2019 Society of Chemical Industry
Overexpression of a Monocot Acyl‐CoA‐Binding Protein Confers Broad‐Spectrum Pathogen Protection in a Dicot
Authors: Panthapulakkal Narayanan Saritha , Liao Pan , Taylor Paul W. J. , Lo Clive , Chye Mee‐Len
Published: May 2019

Plants are continuously infected by various pathogens throughout their lifecycle. Previous studies have reported that the expression of Class III acyl‐CoA‐binding proteins (ACBPs) such as the Arabidopsis ACBP3 and rice ACBP5 were induced by pathogen infection. Transgenic Arabidopsis AtACBP3‐overexpressors (AtACBP3‐OEs) displayed enhanced protection against the bacterial biotroph, Pseudomonas syringae, although they became susceptible to the fungal necrotroph Botrytis cinerea. A Class III ACBP from a monocot, rice (Oryza sativa) OsACBP5 was overexpressed in the dicot Arabidopsis. The resultant transgenic Arabidopsis lines conferred resistance not only to the bacterial biotroph P. syringae but to fungal necrotrophs (Rhizoctonia solani, B. cinerea, Alternaria brassicicola) and a hemibiotroph (Colletotrichum siamense). Changes in protein expression in R. solani‐infected Arabidopsis OsACBP5‐overexpressors (OsACBP5‐OEs) were demonstrated using proteomic analysis. Biotic stress‐related proteins including cell wall‐related proteins such as FASCILIN‐LIKE ARABINOGALACTAN‐PROTEIN10, LEUCINE‐RICH REPEAT EXTENSIN‐LIKE PROTEINS, XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE PROTEIN4, and PECTINESTERASE INHIBITOR18; proteins associated with glucosinolate degradation including GDSL‐LIKE LIPASE23, EPITHIOSPECIFIER MODIFIER1, MYROSINASE1, MYROSINASE2, and NITRILASE1; as well as a protein involved in jasmonate biosynthesis, ALLENE OXIDE CYCLASE2, were induced in OsACBP5‐OEs upon R. solani infection. These results indicated that upregulation of these proteins in OsACBP5‐OEs conferred protection against various plant pathogens.
Hip Radiograph Findings in Patients Aged 40 Years and Under with Posterior Pelvic Pain
Authors: Prather Heidi , Decker Gregory , Bonnette Michael , Simpson Scott , Hunt Devyani , Sahrmann Shirley , Cheng Abby , Nepple Jeffrey
Published: May 2019

Background

Several sacroiliac joint (SIJ) provocative tests used to assess posterior pelvic pain involve moving and stressing the hip. It is unknown if there is a subgroup of patients with posterior pelvic pain who have underlying hip deformity that could potentially influence performance and interpretation of these tests.

Objective

To describe the prevalence of radiographic hip deformity and hip osteoarthritis in a group of adults 40 years old and under who met the clinical diagnostic criteria for treatment of posterior pelvic pain with an image guided intra‐articular SIJ injection.

Design

Retrospective cohort study.

Setting

Tertiary university orthopedic department

Patients (or Participants)

One hundred and forty‐eight patients were evaluated (83% (123/148) female; mean age 31.3 ± 6.2 years). All had completed a trial of comprehensive noninvasive treatment for posterior pelvic pain and had a minimum of three positive SIJ provocative tests on physical examination.

Methods

Retrospective review identified patients undergoing SIJ injection for pain recommended and performed by seven physiatrists between 2011 and 2017. Hip radiographs were read by a physician with expertise in hip measurements with previously demonstrated excellent intrarater reliability.

Main Outcome Measurements

Percentage of patients with hip deformity findings.

Results

No patients meeting the inclusion criteria had significant radiographic hip osteoarthritis (Tonnis ≥2 indicating moderate or greater radiographic hip osteoarthritis) and 4/148 (3%) were found to have mild radiographic hip osteoarthritis. Prearthritic hip disorders were identified in 123 (83%, 95% CI: 76, 89%) patients. For those patients with prearthritic hip disorders, measurements consistent with femoroacetabular impingement (FAI) were seen in 61 (41%) patients, acetabular dysplasia in 49 (33%) patients, and acetabular retroversion in 85 (57%) patients. Acetabular retroversion was identified in 43% (crossover sign) and 39% (prominent ischial spine) of patients.

Conclusions

Approximately 57% of adult patients under the age of 40 years with the clinical symptom complex of SIJ pain were found to have radiographic acetabular retroversion. This is a higher percentage than the 5%‐15% found in asymptomatic people in the current literature. Further study is needed to assess links between hip structure, hip motion, and links to pelvic pain including peri and intra‐articular SIJ pain.

Level of Evidence

III
Controlling and quantifying protein concentration in Escherichia coli
Authors: Speer Shannon L. , Guseman Alex J. , Patteson Jon B. , Ehrmann Brandie M. , Pielak Gary J.
Published: May 2019

The cellular environment is dynamic and complex, involving thousands of different macromolecules with total concentrations of hundreds of grams per liter. However, most biochemistry is conducted in dilute buffer where the concentration of macromolecules is less than 10 g/L. High concentrations of macromolecules affect protein stability, function, and protein complex formation, but to understand these phenomena fully we need to know the concentration of the test protein in cells. Here, we quantify the concentration of an overexpressed recombinant protein, a variant of the B1 domain of protein G, in Tuner (DE3)™ Escherichia coli cells as a function of inducer concentration. We find that the protein expression level is controllable, and expression saturates at over 2 mM upon induction with 0.4 mM isopropyl β‐d‐thiogalactoside. We discuss the results in terms of what can and cannot be learned from in‐cell protein NMR studies in E. coli.
Examination of the nucleotide‐linked assembly mechanism of E. coli ClpA
Authors: Duran Elizabeth C. , Lucius Aaron L.
Published: May 2019

Escherichia coli ClpA is a AAA+ (ATPase Associated with diverse cellular Activities) chaperone that catalyzes the ATP‐dependent unfolding and translocation of substrate proteins targeted for degradation by a protease, ClpP. ClpA hexamers associate with one or both ends of ClpP tetradecamers to form ClpAP complexes. Each ClpA protomer contains two nucleotide‐binding sites, NBD1 and NBD2, and self‐assembly into hexamers is thermodynamically linked to nucleotide binding. Despite a number of studies aimed at characterizing ClpA and ClpAP‐catalyzed substrate unfolding and degradation, respectively, to date the field is unable to quantify the concentration of ClpA hexamers available to interact with ClpP for any given nucleotide and total ClpA concentration. In this work, sedimentation velocity studies are used to quantitatively examine the self‐assembly of a ClpA Walker B variant in the presence of ATP. In addition to the hexamerization, we observe the formation of a previously unreported ClpA dodecamer in the presence of ATP. Further, we report apparent equilibrium constants for the formation of each ClpA oligomer obtained from direct boundary modeling of the sedimentation velocity data. The energetics of nucleotide binding to NBD1 and NBD2 are revealed by examining the dependence of the apparent association equilibrium constants on free nucleotide concentration.
Gauge PDE and AKSZ‐type Sigma Models
Authors: Grigoriev Maxim , Kotov Alexei
Published: May 2019

A gauge PDE is a natural notion which arises by abstracting what physicists call a local gauge field theory defined in terms of BV‐BRST differential (not necessarily Lagrangian). We study supergeometry of gauge PDEs paying particular attention to globally well‐defined definitions and equivalences of such objects. We demonstrate that a natural geometrical language to work with gauge PDEs is that of Q‐bundles. In particular, we demonstrate that any gauge PDE can be embedded into a super‐jet bundle of the Q‐bundle. This gives a globally well‐defined version of the so‐called parent formulation. In the case of reparameterization‐invariant systems, the parent formulation takes the form of an AKSZ‐type sigma model with an infinite‐dimensional target space.
Higher Gauge Structures in Double and Exceptional Field Theory
Authors: Hohm Olaf , Samtleben Henning
Published: May 2019

We review the higher gauge symmetries in double and exceptional field theory from the viewpoint of an embedding tensor construction. This is based on a (typically infinite‐dimensional) Lie algebra and a choice of representation R. The embedding tensor is a map from the representation space R into satisfying a compatibility condition (‘quadratic constraint'). The Lie algebra structure on is transported to a Leibniz–Loday algebra on R, which in turn gives rise to an ‐structure. We review how the gauge structures of double and exceptional field theory fit into this framework.
Categorical Equivalence and the Renormalization Group
Authors: Sharpe Eric
Published: May 2019

In this article we review how categorical equivalences are realized by renormalization group flow in physical realizations of stacks, derived categories, and derived schemes. We begin by reviewing the physical realization of sigma models on stacks, as (universality classes of) gauged sigma models, and look in particular at properties of sigma models on gerbes (equivalently, sigma models with restrictions on nonperturbative sectors), and ‘decomposition,’ in which two‐dimensional sigma models on gerbes decompose into disjoint unions of ordinary theories. We also discuss stack structures on examples of moduli spaces of SCFTs, focusing on elliptic curves, and implications of subtleties there for string dualities in other dimensions. In the second part of this article, we review the physical realization of derived categories in terms of renormalization group flow (time evolution) of combinations of D‐branes, antibranes, and tachyons. In the third part of this article, we review how Landau–Ginzburg models provide a physical realization of derived schemes, and also outline an example of a derived structure on a moduli spaces of SCFTs.
Higher Forms and Membranes in 4D Supergravities
Authors: Bandos I. , Farakos F. , Lanza S. , Martucci L. , Sorokin D.
Published: May 2019

We review the dynamical generation of coupling constants in 4D supergravity by means of gauge three‐form fields. The latter are introduced as components of particular chiral supermultiplets and can be coupled to membranes preserving local supersymmetry. Such a set‐up naturally arises from type‐II string compactifications on Calabi–Yau manifolds with fluxes. We present generic 4D supergravity models with three‐form multiplets and study domain wall solutions supported by membranes, which interpolate between vacua with different values of the cosmological constant.
Effective Actions for σ‐Models of Poisson–Lie Type
Authors: Jurčo Branislav , Vysoký Jan
Published: May 2019

(Quasi‐)Poisson–Lie T‐duality of string effective actions is described in the framework of generalized geometry of Courant algebroids. The approach is based on a generalization of Riemannian geometry in the context of Courant algebroids, including a proper version of a Levi‐Civita connection. In our approach, the dilaton field is encoded in a Levi‐Civita connection and its form is determined by the Courant algebroid geometry. Explicit examples of background solutions are provided using the approach developed in the paper.