bluuebunny/crossref_metadata_2025 huggingface dataset:
Store-brand introduction and production arrangement in the presence of multiple retailers
Authors: Cheng Rong , Ma Weimin , Ke Hua
Published: March 2019

Store brands play an increasingly important role in retailing business, leading more and more retailers to introduce store brands. Abundant research focuses on competition between store brands and national brands and counterstrategies that national-brand manufacturers can take to counter store-brand introduction. A little research studies the store-brand production issue, however, all under single-retailer scenarios. To approach the real world, we employ game theory to model interaction between a national-brand manufacturer and multiple locally monopolist retailers, one of whom has capability and motivation to introduce a store brand. Five Stackelberg games are build and solved to investigate: how the presence of the non-store-brand retailers affects the store-brand retailer’s decision on and profitability in the store-brand introduction; how the store-brand retailer should arrange store-brand production; whether there is a win–win situation where both the store-brand retailer and the national-brand manufacturerare better off with the latter producing the store brand. Accordingly, our study offers a novel rationale for why so many, especially leading, national-brand manufacturers are involved in the store-brand production. Some useful managerial suggestions are proposed on the store-brand introduction and production arrangement.
„Two-Phase Treatment“ und skelettale Klasse III
Authors: Stamm Thomas
Published: March 2019

Das sogenannte „Two-Phase Treatment“ gerät immer wieder in den Fokus der ökonomisch orientierten Wissenschaft. Diese Überprüfung ist sinnvoll, stehen doch Vorwürfe wie Übertherapie, zusätzliche Kosten und Belastungen für Patient, Eltern und Arzt im Raum. In dieser kontroversen Diskussion scheint die Kenntnis über grundlegende Konzepte einer Frühbehandlung vollkommen verloren gegangen zu sein. Die Überprüfung medizinischer Hypothesen tritt zugunsten einer gerätelastigen Forschung in den Hintergrund, die den Fokus auf die Apparatur und nicht auf den kausalen Wirkmechanismus gerichtet hat. Begiffe wie „fixed Appliances“, „removable Appliances” als auch “One-, Two-Phase Treatment” simplifizieren die Konzepte der Funktionskieferorthopädie, der Orofazialen Orthopädie sowie der Funktionellen Orthopädie und tragen damit zur Fehlinterpretation aktueller Studien bei. Die Anwendungen im kraniofazialen Skelett lassen sich weit zurückverfolgen, sodass die Kieferorthopädie als Teilgebiet der funktionellen Orthopädie gesehen und nicht mit Mechaniken der Orthodontie verglichen werden kann.
Kraniosynostosen – komplexe interdisziplinäre Therapie
Authors: Hemprich Alexander , Klapper Horst-Uwe , Dannhauer Karl-Heinz
Published: March 2019

Im Rahmen dieser Übersichtsarbeit sollen exemplarisch typische interdisziplinäre Behandlungsschritte bei Patienten mit Kraniosynostosen (Crouzon-Syndrom) sowie die abschließende zahnärztliche Versorgung und Weiterbetreuung durch den Hauszahnarzt als Beispiele für komplexe Rehabilitationen und Nachsorgestrategien vorgestellt werden.

Dies ist auch aus kieferorthopädischer Sicht ausgesprochen relevant, da die vielfältigen zahnärztlichen Maßnahmen Einfluss auf die kieferorthopädische Behandlungsplanung haben.
Screeninginstrument für Angst bei Menschen mit Intelligenzminderung: Deutsche Version der „Glasgow Anxiety Scale for people with an Intellectual Disability“ (GAS-ID)
Authors: Müller Katrin , Kufner Katharina , Prange Kathrin , Bengel Jürgen
Published: March 2019

Ziel Übersetzung und Validierung der Glasgow Anxiety Scale for people with an Intellectual Disability (GAS-ID).

Methodik Überprüfung psychometrischer Eigenschaften an einer Stichprobe von 34 Erwachsenen mit Lernbehinderung oder Intelligenzminderung und 38 klinischen Probanden ohne Intelligenzminderung.

Ergebnisse Die GAS-ID erwies sich als reliabel und valide (Sensitivität: 100 %, Spezifität: 87 %).

Schlussfolgerung Die deutsche GAS-ID ist ein vielversprechendes Screeninginstrument. Eine Überarbeitung einzelner Items und Replikation an größeren Stichproben stehen noch aus.
A Graphene Oxide Nanosheet Supported NHC–Palladium Complex as a Highly Efficient and Recyclable Suzuki Coupling Catalyst
Authors: Qian Yingjie , So Jaeil , Jung Sang-Yung , Hwang Sosan , Jin Myung-Jong , Shim Sang
Published: March 2019

A practical heterogeneous catalyst was prepared by anchoring a triazine-tethered N-heterocyclic carbene (NHC)–palladium complex on the surface of graphene oxide (GO) nanosheets. The immobilized complex was characterized by X-ray photoelectron spectroscopy, field-emission transmission electron microscopy, energy-dispersive X-ray spectroscopy, and surface area analysis. It proved to be a highly active and durable heterogeneous catalyst for Suzuki coupling reactions. At room temperature, the use of this catalyst enabled the preparation of various biaryls and heterobiaryls in short reaction times. The catalytic system could be recycled at least 10 times with almost consistent activity. The results reveal that the stable palladium complex is strongly anchored on the surface of GO nanosheets. Interestingly, an open planar network of the GO nanosheet support plays a role during the catalytic process in enhancing the catalytic activity.
Nutrition and Exercise Strategies to Prevent Excessive Pregnancy Weight Gain: A Meta-analysis
Authors: Craemer Katherine , Sampene Emmanuel , Safdar Nasia , Antony Kathleen , Wautlet Cynthia
Published: March 2019

Objective To evaluate nutrition-only, exercise-only, and nutrition-plus-exercise interventions for optimizing gestational weight gain (GWG) based on the 2009 Institute of Medicine (IOM) guidelines.

Study PubMed, Google Scholar, and 2015 Cochrane Review were searched. Analysis of variance was used to determine if significant GWG differences exist between strategies, with additional subanalyses on overweight (OV) or obese women based on 2009 IOM guidelines.

Results Of 66 identified studies, 31 contributed data (n = 8,558). Compared with routine prenatal care, nutrition-only interventions were significantly associated with reduced GWG and are most likely to produce weight gain within IOM recommendations (p = 0.013). Exercise-only (p = 0.069) and nutrition-plus-exercise (p = 0.056) interventions trended toward GWG within IOM guidelines, but did not reach statistical significance. Supervised (p = 0.61) and unsupervised (p = 0.494) exercise programs had similar effectiveness. Subanalyses on OV or obese women produced similar results to studies that did not differentiate results based on body mass index: nutrition only (p = 0.011), exercise only (p = 0.308), and nutrition plus exercise (p = 0.129).

Conclusion Preventing excessive GWG is crucial, especially for OV or obese women. In the current study, nutrition-based intervention is the health system strategy that showed significant impact on preventing excessive GWG compared with routine prenatal care. Among women who are OV or have obesity, nutrition-only interventions hold the most promise compared with routine prenatal care.
Antibiotics during Intrauterine Balloon Tamponade Is Associated with a Reduction in Endometritis
Authors: Wong Melissa S. , Dellapiana Gabriela , Greene Naomi , Gregory Kimberly D.
Published: March 2019

Objective To evaluate whether prophylactic antibiotics at the time of placement of an intrauterine balloon tamponade (IBT) is associated with a reduction in postpartum endometritis.

Study Design Retrospective cohort study of patients who received an IBT from January 1, 2012, to December 12, 2016. Patients were included if the IBT remained in place at least 2 hours and excluded if chorioamnionitis was present. Patients who received prophylactic antibiotics at the time of IBT placement were compared with those who did not.

Results A total of 149 subjects received an IBT; 36 were excluded due to early removal or chorioamnionitis. Of the remaining, 59 received prophylactic antibiotics and 54 did not. Baseline characteristics were similar between the groups except mode of delivery. The majority (65%) of those who did not receive prophylactic antibiotics had a cesarean delivery (p = 0.03). The overall incidence of endometritis was 15%. The incidence of endometritis was greater among those patients who did not receive prophylactic antibiotics compared with those who did (5 vs. 26%; p < 0.002; odds ratio [OR]: 6.53; 95% confidence interval [CI]: 1.76–24.25). This association remained after adjustment for mode of delivery and receiving group B Streptococcus antibiotics prior to delivery (adjusted OR: 5.9; 95% CI: 1.58–22.35).

Conclusion Prophylactic antibiotics were associated with a reduction in postpartum endometritis among patients receiving an IBT.
Entstauungstherapie in Orthopädie und
Chirurgie
Authors: Streicher Eva-Maria
Published: March 2019

2017 wurde die Leitlinie zur Therapie und Diagnostik der Lymphödeme
veröffentlicht. Eva-Maria Streicher war in der Arbeitsgruppe Konservative
Therapie mit vertreten. Im Rahmen einer Literatrurecherche wurde der Frage
nachgegangen, welche Maßnahme derzeit die effektivste Therapie ist. Für die
Komplexe Physikalische Entstauungstherapie konnte die höchste
Effektivität nachgewiesen werden, nicht aber die Manuelle Lymphdrainage als
Monotherapie bestätigt werden. Die klassischen Säulen der KPE wurden um die
Säule des Selbstmanagments erweitert.
Charge migration model for the impedance response of DI water
Authors: SatyanarayanaRaju CHSRV , Krishnamurthy Chitti Venkata
Published: March 2019

A charge migration model is proposed to model the impedance response of water, containing intrinsic (auto dissociated) and extrinsic ions (from dissolved gases), measured in the frequency range 1mHz − 30MHz with stainless steel electrodes. The observed response may be broadly classified into two frequency regions (region I: 10 kHz < f < 20 MHz and region II: 200μ Hz < f < 10 kHz). Region I may be characterized by bulk conduction and geometric capacitance leading to a relaxation-like response and a dispersion-free conductivity. Region II may be characterized by dispersive effects associated with space-charge layer in the vicinity of the electrodes. The proposed model is built on the notion that the process of space charge formation is mutually exclusive from the process of ionic conduction. Accordingly, it assumes that a fraction of the charge carriers participates in the conduction process and the remaining fraction contributes to the capacitance associated with space charge formation. When fitted to the observed impedance response, through equivalent circuit models, the charge concentration fraction exhibits a power law dependence on the frequency. The model is fairly general in its scope and may provide an alternate route to understand the internal processes and prompt further investigations.
Absorbing boundary conditions for time-dependent Schrödinger equations: A density-matrix formulation
Authors: Li Xiantao
Published: March 2019

This paper presents some absorbing boundary conditions for simulations based on the time-dependent Schrödinger equations. The boundary conditions are expressed in terms of the elements of the density-matrix, and it is derived from the full model over a much larger domain. To make the implementation much more efficient, several approximations for the convolution integral will be constructed with guaranteed stability. These approximations lead to modified density-matrix equations at the boundary. The effectiveness is examined via numerical tests.
Semi-hard magnetic nanocomposites based on out-of-equilibrium Fe2+δNb and Fe2+δTa Laves phases
Authors: Gabay A. M. , Hadjipanayis G. C.
Published: March 2019

Melt-spun Fe100-xNbx and Fe100-xTax alloys consisting of a hexagonal (C14) Laves phase and an iron-based bcc phase were found to exhibit room-temperature coercivities up to 0.45 and 0.48 kOe, respectively. The non-equilibrium C14 structures in the melt-spun alloys are characterized by a smaller unit cell volume, a higher Curie temperature and, presumably, a greater concentration of Fe compared to the C14 structures in the alloys annealed at 1533 K. The room-temperature coercivity, which correlates with the C14 lattice contraction, is believed to be caused by the magnetocrystalline anisotropy of the non-equilibrium Laves phase with the latter being magnetically coupled with the Fe phase via an intergranular exchange interaction. On the other hand, a coercivity of around 0.3 kOe persists in the melt-spun alloys above the Curie temperature of the C14 phase. This high-temperature coercivity may originate from the shape or strain anisotropy of the Fe phase particles. The energy density of the reported two-phase alloys is not sufficiently high to consider them potential hard magnetic materials. However, the pure non-equilibrium Fe2+δNb and Fe2+δTa compounds may be of interest if they can be isolated and textured.
An in situ method on kinetics of gas hydrates
Authors: Masoudi Ali , Jafari Parham , Nazari Masoumeh , Kashyap Varun , Eslami Bahareh , Irajizad Peyman , Ghasemi Hadi
Published: March 2019

Gas hydrate formation is a high-risk and common flow assurance problem in subsea oil production plants. The modern strategies to mitigate hydrate formation have switched from thermodynamic inhibition to risk management. In this new mitigation strategy, hydrate formation is allowed as long as it does not lead to plugging of pipelines. Thus, understanding the growth kinetics of gas hydrates plays a critical role in risk management strategies. Here, we report a new accurate and in situ approach to probe the kinetics of gas hydrate formation. This approach is based on the hot-wire method, which probes the thermal properties of the medium surrounding the hot-wire. As the thermal properties of gas hydrate and its initial constituents are different, variation in these properties is used to probe kinetics of hydrate growth front. Through this in situ method, we determine kinetics of cyclopentane hydrate formation in both mixing and flow conditions. The findings show that at ambient pressure and a temperature of 1-2 °C, the hydrate formation rate under mixing condition varies between 1.9 × 10−5 and 3.9 × 10−5 kg m−2 s−1, while in flow condition, this growth rate drops to 4.5 × 10−6 kg m−2 s−1. To our knowledge, this is the first reported growth rate of cyclopentane hydrate. This in situ approach allows us to probe kinetics of hydrate formation where there is no optical access and provides a tool to rationally design risk management strategies for subsea infrastructures.
4-Bromobiphenyl: Long-lived molecular anion formation and competition between electron detachment and dissociation
Authors: Asfandiarov N. L. , Pshenichnyuk S. A. , Rakhmeyev R. G. , Tuktarov R. F. , Zaitsev N. L. , Vorob’ev A. S. , Kočišek J. , Fedor J. , Modelli A.
Published: March 2019

Electron attachment to the 4-bromobiphenyl molecule and the decay channels of its molecular anion were investigated by means of Dissociative Electron Attachment (DEA) spectroscopy with two different spectrometers. The first apparatus is equipped with a static magnet mass analyzer (Ufa group) and the second one with a quadrupole mass filter (Prague group). The dominant DEA channel at low electron energy leads to formation of Br− negative fragments. Long-lived (τa = 40 µs at the temperature of 80 °C) molecular negative ions were detected only in the Ufa experiment. We explored the involved potential energy surfaces and found that the molecular anion has two distinct structures with the C–Br distances of 1.92 Å and 2.8 Å. The statistical model based on the Arrhenius approximation fully explains the experimental observations and sheds light on the earlier anion dissociation kinetic studies in solution.
Tracking picosecond strain pulses in heterostructures that exhibit giant magnetostriction
Authors: Zeuschner S. P. , Parpiiev T. , Pezeril T. , Hillion A. , Dumesnil K. , Anane A. , Pudell J. , Willig L. , Rössle M. , Herzog M. , von Reppert A. , Bargheer M.
Published: March 2019

We combine ultrafast X-ray diffraction (UXRD) and time-resolved Magneto-Optical Kerr Effect (MOKE) measurements to monitor the strain pulses in laser-excited TbFe2/Nb heterostructures. Spatial separation of the Nb detection layer from the laser excitation region allows for a background-free characterization of the laser-generated strain pulses. We clearly observe symmetric bipolar strain pulses if the excited TbFe2 surface terminates the sample and a decomposition of the strain wavepacket into an asymmetric bipolar and a unipolar pulse, if a SiO2 glass capping layer covers the excited TbFe2 layer. The inverse magnetostriction of the temporally separated unipolar strain pulses in this sample leads to a MOKE signal that linearly depends on the strain pulse amplitude measured through UXRD. Linear chain model simulations accurately predict the timing and shape of UXRD and MOKE signals that are caused by the strain reflections from multiple interfaces in the heterostructure.
On the hydration of DOPE in solution
Authors: Rhys Natasha H. , Duffy Imogen B. , Sowden Christopher L. , Lorenz Christian D. , McLain Sylvia E.
Published: March 2019

The atomic-scale hydration structure around the 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) headgroup in a chloroform/water solution has been investigated using neutron diffraction enhanced by isotopic substitution and NMR, coupled with empirical potential structure refinement and molecular dynamics simulations. The results obtained show the preferential binding sites for water molecules on the DOPE headgroups, with the most predominant interactions being with the ammonium and phosphate groups. Interestingly, the level of hydration, as well as the association of DOPE molecules, varies according to the simulation method used. The results here suggest the presence of a tight water network around these lipid headgroups that could affect the permeability of the membrane for lipid-mediated diffusion.
Helium-hydrogen immiscibility at high pressures
Authors: Wang Yu , Zhang Xiao , Jiang Shuqing , Geballe Zachary M. , Pakornchote Teerachote , Somayazulu Maddury , Prakapenka Vitali B. , Greenberg Eran , Goncharov Alexander F.
Published: March 2019

Hydrogen and helium are the most abundant elements in the universe, and they constitute the interiors of gas giant planets. Thus, their equations of states, phase, chemical state, and chemical reactivity at extreme conditions are of great interest. Applying Raman spectroscopy, visual observation, and synchrotron X-ray diffraction in diamond anvil cells, we performed experiments on H2–He 1:1 and D2–He 1:10 compressed gas mixtures up to 100 GPa at 300 K. By comparing with the available data on pure bulk materials, we find no sign of miscibility, chemical reactivity, and new compound formation. This result establishes a new baseline for future investigations of miscibility in the He–H2 system at extreme P-T conditions.
On the microwave absorption of magnetic nanofluids based on barium hexaferrite in the S and X bands prepared by pulsed laser ablation in liquid
Authors: Archana V. N. , Mani Manoj , Johny Jacob , Vinayasree S. , Mohanan P. , Garza-Navarro Marco A. , Shaji Sadasivan , Anantharaman M. R.
Published: March 2019

Magnetic nanofluids can be prepared by dispersing surfacted nanoparticles in an appropriate carrier medium. The microwave absorbing properties of a magnetic nanofluid based on barium hexaferrite (BAF) is promising since BAF is a good microwave absorber. Surfacted BAF particles prepared by Pulsed Laser Ablation in Liquid (PLAL) overcome agglomeration and are stable under normal conditions. The evaluation of parameters namely ε′, ε″, μ′ and μ″ (real and imaginary parts of permittivity and permeability) will aid in the determination of the microwave absorbing properties since these parameters can be employed to model the optimum thickness of the absorber for maximum absorption using surface impedance equations. Moreover, the fluid can be coated with the required thicknesses on a surface once these parameters are evaluated and modelled. A magnetic nanofluid based on BAF is synthesized using PLAL and its microwave absorbing properties are evaluated and presented here. It is found that they serve as good absorbers in the S and X bands.
Calculation of solvation free energy utilizing a constrained QM/MM approach combined with a theory of solutions
Authors: Takahashi Hideaki , Kambe Hiroyuki , Morita Akihiro
Published: March 2019

In an extended QM/MM (quantum mechanical/molecular mechanical) description of a solution, the solvent molecules surrounding the solute are incorporated into the QM region besides the solute. In a recent development, we introduced a simple and efficient method, referred to as boundary constraint with correction (BCC), to prevent the diffusion of the QM solvent into the bulk. The major purpose of the present work is to develop a method to compute the solvation free energy of a QM solute in an extended QM/MM simulation by means of the BCC method. The strategy of our development is to utilize the QM/MM-ER method which combines the QM/MM simulation and the theory of solutions termed energy representation (ER) to expedite the free energy calculation. A theory is, then, formulated to couple QM/MM-ER and the BCC method on the basis of the statistical mechanics. A notable feature of our method is that the effect of the constraint potentials on the free energy completely vanishes when the force field of the QM solvent coincides with that of the MM solvent. The method is applied to the calculations of the solvation free energies of a water molecule and a hydronium ion in water solutions. It turns out that the present method can offer a significant improvement in describing the free energy Δν of the hydronium ion, in particular, as compared with the conventional QM/MM approach. Explicitly, Δν is obtained as −98.0 kcal/mol showing a good agreement with an experimental value of −103.5 kcal/mol, while −86.1 kcal/mol by the conventional method.
Failure mechanism of Au@Co9S8 yolk-shell anode in Li-ion batteries unveiled by in-situ transmission electron microscopy
Authors: Han Shaobo , Zhu Yuanmin , Cai Chao , Zhu Jiakun , Han Wenbin , Chen Lang , Zu Xiaotao , Yang Hui , Gu Meng
Published: March 2019

Co9S8 has been regarded as a desirable anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity. However, lithium (Li) insertion caused large volume expansion, and subsequent pulverization and capacity decay are the major challenges for its practical applications in commercial LIBs. In this work, we design an Au@Co9S8 yolk-shell nanoparticle (NP) anode and use in-situ transmission electron microscopy to study the structural, morphological, and chemical evolutions in the NPs during lithiation. Our experimental results reveal that Li insertion leads to the volume expansion of the lithiated Co9S8 shell dominantly in the outward direction, and the conversion reaction between Li and Co9S8 induces the formation of a two-phase shell with metallic Co clusters dispersed in the as-formed Li2S matrix. With corroboration of chemo-mechanical simulations, we elucidate that the lithiation-generated comparative softer phase together with the inner stiffer unlithiated Co9S8 phase contributes to the outward only deformation pattern. In addition, the insulating nature of the as-formed Li2S results in an unexpected non-reactive Au yolk during lithiation. Our findings elucidate the significance of considering the dynamical phase transformations of active materials (i.e., Co9S8) for LIBs and provide valuable insights into the rational design of new generation high-performance LIBs.
Overcoming lag phase: do regenerative attributes onset Acacia dealbata spread in a newly invaded system?
Authors: Spalazzi Florencia , Tecco Paula A. , Funes Guillermo
Published: March 2019

Ecological theory predicts that the success of exotic plants in new environments depends on a combination of ecological attributes. Requirements for germination and seedling traits are the main components in the regenerative niche, and largely determine the success of exotic species in a new environment. Acacia dealbata Link is an Australian species with a great invasive potential. In Chaco Mountains (central Argentina), it seems to be undergoing a lag phase, as some local dominance in the form of dense monospecific patches has been recorded, although restricted to few disperse populations. In the present study we assessed which functional traits would allow this global invader to successfully overcome its lag phase, and what conditions could benefit or limit this process. Imbibition and germination experiments were designed, and included four temperature regimes in light and in continuous darkness. Additionally, germination response to light quality and simulation fire experiment was also conducted. Further, soil samples were taken to determine the size of the soil seed bank, and a morpho-functional characterisation of seedlings was conducted. Despite the absence of a consistent fire-stimulated germination response, our findings were in line with generalist germination requirements. Physical seed dormancy, large seed bank, broad temperature and light germination requirements, and fast-growing seedlings make this species a potential invader in this mountain system, and suggest that these regenerative attributes might help A. dealbata to overcome its present lag phase. Findings show that the efficiency of management decreases and the related economic cost increases as the time since invasion increases, so early intervention will be key in preventing spread of this species thorough this mountain region.
Tellurite-dependent blackening of bacteria emerges from the dark ages
Authors: Presentato Alessandro , Turner Raymond J. , Vásquez Claudio C. , Yurkov Vladimir , Zannoni Davide
Published: March 2019

Environmental contextAlthough tellurium is a relatively rare element in the earth’s crust, its concentration in some niches can be naturally high owing to unique geology. Tellurium, as the oxyanion, is toxic to prokaryotes, and although prokaryotes have evolved resistance to tellurium, no universal mechanism exists. We review the interaction of tellurite with prokaryotes with a focus on those unique strains that thrive in environments naturally rich in tellurium. AbstractThe timeline of tellurite prokaryotic biology and biochemistry is now over 50 years long. Its start was in the clinical microbiology arena up to the 1970s. The 1980s saw the cloning of tellurite resistance determinants while from the 1990s through to the present, new strains were isolated and research into resistance mechanisms and biochemistry took place. The past 10 years have seen rising interest in more technological developments and considerable advancement in the understanding of the biochemical mechanisms of tellurite metabolism and biochemistry in several different prokaryotes. This research work has provided a list of genes and proteins and ideas about the fundamental metabolism of Te oxyanions. Yet the biomolecular mechanisms of the tellurite resistance determinants are far from established. Regardless, we have begun to see a new direction of Te biology beyond the clinical pathogen screening approaches, evolving into the biotechnology fields of bioremediation, bioconversion and bionanotechnologies and subsequent technovations. Knowledge on Te biology may still be lagging behind that of other chemical elements, but has moved beyond its dark ages and is now well into its renaissance.
A simple method for the analysis of neonicotinoids and their metabolites in human urine
Authors: Honda Masato , Robinson Morgan , Kannan Kurunthachalam
Published: March 2019

Environmental contextThe agricultural usage of neonicotinoid insecticides is a matter of environmental and human health concern, requiring assessment of human exposure. The implementation of a human exposure assessment is dependent on analytical methods to quantitatively determine neonicotinoids in human urine. We describe a simple and sensitive method suitable for monitoring human exposure to neonicotinoids and their metabolites.
AbstractAn analytical method for measuring seven neonicotinoid insecticides and four of their metabolites in human urine was developed based on solid phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry. The accuracy and precision of the method at three fortification levels (0.25, 2.50 and 10.0ngmL−1) of the target analytes in 500µL of urine were 83.7–119% and 2.0–11.3%, respectively. The average inter-batch precision (fortification level: 2.50ngmL−1) was 5.5–11.9%, and the limits of quantification ranged from 0.01 to 0.05ngmL−1 depending on the neonicotinoid. The method was applied to 20 spot urine samples collected from healthy adults in Albany, New York, United States. At least two of the neonicotinoids or their metabolites were found in each urine sample (median concentration: nd–0.43ngmL−1). The method is simple, sensitive and precise, and is well suited for measuring neonicotinoids in human urine for future exposure assessment studies.
Age-related inflammation triggers skeletal stem/progenitor cell dysfunction
Authors: Josephson Anne Marie , Bradaschia-Correa Vivian , Lee Sooyeon , Leclerc Kevin , Patel Karan S. , Muinos Lopez Emma , Litwa Hannah P. , Neibart Shane S. , Kadiyala Manasa , Wong Madeleine Z. , Mizrahi Matthew M. , Yim Nury L. , Ramme Austin J. , Egol Kenneth A. , Leucht Philipp
Published: March 2019

Significance

As we age, our capacity for tissue repair and regeneration in response to injury declines. Accordingly, bone repair is delayed and impaired in older patients. At the cornerstone of bone healing is the skeletal stem/progenitor cell (SSPC), whose function and number diminishes with age. However, the mechanisms driving this decline remain unclear. Here, we identify age-associated inflammation (“inflamm-aging”) as the main culprit of SSPC dysfunction and provide support for a central role of NF-κB as a mediator of inflamm-aging. Our results show that modification of the inflammatory environment may be a translational approach to functionally rejuvenate the aged SSPC, thereby improving the regenerative capacity of the aged skeleton.
Lysosome inhibition sensitizes pancreatic cancer to replication stress by aspartate depletion
Authors: Elliott Irmina A. , Dann Amanda M. , Xu Shili , Kim Stephanie S. , Abt Evan R. , Kim Woosuk , Poddar Soumya , Moore Alexandra , Zhou Lei , Williams Jennifer L. , Capri Joseph R. , Ghukasyan Razmik , Matsumura Cynthia , Tucker D. Andrew , Armstrong Wesley R. , Cabebe Anthony E. , Wu Nanping , Li Luyi , Le Thuc M. , Radu Caius G. , Donahue Timothy R.
Published: March 2019

Significance

Pancreatic cancer is notoriously treatment resistant. These tumors rely on lysosome-dependent recycling pathways to generate substrates for metabolism, which are inhibited by chloroquine (CQ) and its derivatives. However, clinical efficacy of CQ as a monotherapy or combined with standard-of-care regimens has been limited. Using an unbiased kinome screen, we identify replication stress as an induced vulnerability of CQ due to impaired de novo nucleotide biosynthesis and find that combination treatment with CQ and a replication stress response inhibitor is synthetically lethal in pancreatic cancer.
Exaggerated heterochiasmy in a fish with sex-linked male coloration polymorphisms
Authors: Bergero Roberta , Gardner Jim , Bader Beth , Yong Lengxob , Charlesworth Deborah
Published: March 2019

It is often stated that polymorphisms for mutations affecting fitness of males and females in opposite directions [sexually antagonistic (SA) polymorphisms] are the main selective force for the evolution of recombination suppression between sex chromosomes. However, empirical evidence to discriminate between different hypotheses is difficult to obtain. We report genetic mapping results in laboratory-raised families of the guppy (
Poecilia reticulata
), a sexually dimorphic fish with SA polymorphisms for male coloration genes, mostly on the sex chromosomes. Comparison of the genetic and physical maps shows that crossovers are distributed very differently in the two sexes (heterochiasmy); in male meiosis, they are restricted to the termini of all four chromosomes studied, including chromosome 12, which carries the sex-determining locus. Genome resequencing of male and female guppies from a population also indicates sex linkage of variants across almost the entire chromosome 12. More than 90% of the chromosome carrying the male-determining locus is therefore transmitted largely through the male lineage. A lack of heterochiasmy in a related fish species suggests that it originated recently in the lineage leading to the guppy. Our findings do not support the hypothesis that suppressed recombination evolved in response to the presence of SA polymorphisms. Instead, a low frequency of recombination on a chromosome that carries a male-determining locus and has not undergone genetic degeneration has probably facilitated the establishment of male-beneficial coloration polymorphisms.
Limited oxygen production in the Mesoarchean ocean
Authors: Ossa Ossa Frantz , Hofmann Axel , Spangenberg Jorge E. , Poulton Simon W. , Stüeken Eva E. , Schoenberg Ronny , Eickmann Benjamin , Wille Martin , Butler Mike , Bekker Andrey
Published: March 2019

Significance

Episodic development of “oxygen oases” during the Archean Eon characterizes the hundreds of millions of years transition to permanent oxygenation in the atmosphere–hydrosphere system at the Great Oxidation Event (∼2.4–2.3 Ga). One of these well-characterized oxygen oases is recorded in Mesoarchean sediments of the Pongola Supergroup. We show that in contrast to the Neoarchean, biological oxygen production in a shallow ocean having Mo-based nitrogen fixation was not sufficient to result in a dissolved nitrogen reservoir that would carry the isotopic effects of an aerobic nitrogen cycle. Nevertheless, it appears that low concentrations of bioavailable phosphorus, rather than nitrogen, suppressed the growth and expansion of oxygenic photosynthesizers and may explain why pervasive and permanent oxygenation was delayed during the Archean Eon.
PTPN14 degradation by high-risk human papillomavirus E7 limits keratinocyte differentiation and contributes to HPV-mediated oncogenesis
Authors: Hatterschide Joshua , Bohidar Amelia E. , Grace Miranda , Nulton Tara J. , Kim Hee Won , Windle Brad , Morgan Iain M. , Munger Karl , White Elizabeth A.
Published: March 2019

Significance

Human papillomaviruses (HPV) uncouple proliferation from differentiation to enable virus replication in epithelial cells. HPV E7 proteins are well established to promote proliferation by binding to and inactivating retinoblastoma family proteins and other cell cycle inhibitors. However, mechanisms by which high-risk HPV oncoproteins inhibit differentiation have not been defined. This paper identifies a mechanism by which high-risk HPV E7 inhibit keratinocyte differentiation. The inhibition of differentiation requires degradation of the cellular protein PTPN14 by high-risk HPV E7, and this degradation is related to the ability of high-risk HPV oncoproteins to immortalize keratinocytes and to cause cancer.
Magnetoelastic hybrid excitations in CeAuAl
3
Authors: Čermák Petr , Schneidewind Astrid , Liu Benqiong , Koza Michael Marek , Franz Christian , Schönmann Rudolf , Sobolev Oleg , Pfleiderer Christian
Published: March 2019

Nearly a century of research has established the Born–Oppenheimer approximation as a cornerstone of condensed-matter systems, stating that the motion of the atomic nuclei and electrons may be treated separately. Interactions beyond the Born–Oppenheimer approximation are at the heart of magneto-elastic functionalities and instabilities. We report comprehensive neutron spectroscopy and ab initio phonon calculations of the coupling between phonons, CEF-split localized 4

f

electron states, and conduction electrons in the paramagnetic regime of

C
e
A
u
A
l

3

, an archetypal Kondo lattice compound. We identify two distinct magneto-elastic hybrid excitations that form even though all coupling constants are small. First, we find a CEF–phonon bound state reminiscent of the vibronic bound state (VBS) observed in other materials. However, in contrast to an abundance of optical phonons, so far believed to be essential for a VBS, the VBS in

C
e
A
u
A
l

3

arises from a comparatively low density of states of acoustic phonons. Second, we find a pronounced anticrossing of the CEF excitations with acoustic phonons at zero magnetic field not observed before. Remarkably, both magneto-elastic excitations are well developed despite considerable damping of the CEFs that arises dominantly by the conduction electrons. Taking together the weak coupling with the simultaneous existence of a distinct VBS and anticrossing in the same material in the presence of damping suggests strongly that similarly well-developed magneto-elastic hybrid excitations must be abundant in a wide range of materials. In turn, our study of the excitation spectra of

C
e
A
u
A
l

3

identifies a tractable point of reference in the search for magneto-elastic functionalities and instabilities.
Amyloid found in human cataracts with two-dimensional infrared spectroscopy
Authors: Alperstein Ariel M. , Ostrander Joshua S. , Zhang Tianqi O. , Zanni Martin T.
Published: March 2019

Significance

Cataract disease causes blindness in over 18 million people due to aggregation of proteins in the normally clear eye lens. There exist conflicting reports about these aggregates in lens tissue due to complications such as extremely high protein concentration. Here, we use two-dimensional infrared (2DIR) spectroscopy to identify amyloid β-sheets in cataract lens tissue. The three 2DIR structural signatures of diagonal peak frequency, anharmonic shift, and cross-peak frequency, as well as our comparison with FTIR measurements, UV irradiation, and light scattering, demonstrate a toolset for protein secondary structure investigation in tissue.
Cryo-EM structures of
Helicobacter pylori
vacuolating cytotoxin A oligomeric assemblies at near-atomic resolution
Authors: Zhang Kaiming , Zhang Huawei , Li Shanshan , Pintilie Grigore D. , Mou Tung-Chung , Gao Yuanzhu , Zhang Qinfen , van den Bedem Henry , Schmid Michael F. , Au Shannon Wing Ngor , Chiu Wah
Published: March 2019

Human gastric pathogen
Helicobacter pylori
(
H. pylori
) is the primary risk factor for gastric cancer and is one of the most prevalent carcinogenic infectious agents. Vacuolating cytotoxin A (VacA) is a key virulence factor secreted by
H. pylori
and induces multiple cellular responses. Although structural and functional studies of VacA have been extensively performed, the high-resolution structure of a full-length VacA protomer and the molecular basis of its oligomerization are still unknown. Here, we use cryoelectron microscopy to resolve 10 structures of VacA assemblies, including monolayer (hexamer and heptamer) and bilayer (dodecamer, tridecamer, and tetradecamer) oligomers. The models of the 88-kDa full-length VacA protomer derived from the near-atomic resolution maps are highly conserved among different oligomers and show a continuous right-handed β-helix made up of two domains with extensive domain–domain interactions. The specific interactions between adjacent protomers in the same layer stabilizing the oligomers are well resolved. For double-layer oligomers, we found short- and/or long-range hydrophobic interactions between protomers across the two layers. Our structures and other previous observations lead to a mechanistic model wherein VacA hexamer would correspond to the prepore-forming state, and the N-terminal region of VacA responsible for the membrane insertion would undergo a large conformational change to bring the hydrophobic transmembrane region to the center of the oligomer for the membrane channel formation.
Ultrahigh strength-ductile medium-Mn steel auto-parts combining warm stamping and quenching & partitioning
Authors: Pan Haijun , Cai Minghui , Ding Hua , Sun Shenghui , Huang Hongshou , Zhang Yisheng
Published: March 2019

A novel application of quenching and partitioning (Q&P) treatment to warm stamping of a warm-rolled medium Mn steel was investigated. The results show that Q&P could improve yield strength of auto-parts from the formation of carbides and twinned martensite, and reduce the yield point elongation for carbon partitioning during Q&P process and a higher dislocation density. Regardless of stamping temperature either the single austenite or dual-phase region, an extraordinary product of strength and ductility (≥24 GPa·%) was achieved, which is two or three times higher than those of hot-stamped boron steels. The combined warm rolling and warm stamping process with Q&P treatment may have potential to implement the application of medium Mn steels for ultrahigh strength-ductile auto-parts.
Tks5 and Dynamin-2 enhance actin bundle rigidity in invadosomes to promote myoblast fusion
Authors: Chuang Mei-Chun , Lin Shan-Shan , Ohniwa Ryosuke L. , Lee Gang-Hui , Su You-An , Chang Yu-Chen , Tang Ming-Jer , Liu Ya-Wen
Published: March 2019

Skeletal muscle development requires the cell–cell fusion of differentiated myoblasts to form muscle fibers. The actin cytoskeleton is known to be the main driving force for myoblast fusion; however, how actin is organized to direct intercellular fusion remains unclear. Here we show that an actin- and dynamin-2–enriched protrusive structure, the invadosome, is required for the fusion process of myogenesis. Upon differentiation, myoblasts acquire the ability to form invadosomes through isoform switching of a critical invadosome scaffold protein, Tks5. Tks5 directly interacts with and recruits dynamin-2 to the invadosome and regulates its assembly around actin filaments to strengthen the stiffness of dynamin-actin bundles and invadosomes. These findings provide a mechanistic framework for the acquisition of myogenic fusion machinery during myogenesis and reveal a novel structural function for Tks5 and dynamin-2 in organizing actin filaments in the invadosome to drive membrane fusion.
On the performance of an ENZ-based sensor using transmission line theory and effective medium approach
Authors: Pacheco-Peña V , Beruete M , Rodríguez-Ulibarri P , Engheta N
Published: March 2019

In this paper we perform an in-depth theoretical study of a sensing platform based on epsilon-near-zero (ENZ) metamaterials. The structure proposed for sensing is a narrow metallic waveguide channel. An equivalent circuit model is rigorously deduced using transmission line theory, considering several configurations for a dielectric body (analyte sample) inserted within the narrow channel, showing good agreement with results obtained from numerical simulations. The transmission line model is able to reproduce even the most peculiar details of the sensing platform response. Its performance is then evaluated by varying systematically the size, position and permittivity of the analyte, and height of the ENZ channel. It is shown that the sensor is capable of detecting changes in the permittivity/refractive index or position even with deeply subwavelength analyte sizes (∼0.05λ
0), giving a sensitivity up to 0.03 m/RIU and a figure of Merit ∼25. The effective medium approach is evaluated by treating the inhomogeneous cross-section of the analyte as a transmission line filled with a homogeneous material.
Spin detection with a micromechanical trampoline: towards magnetic resonance microscopy harnessing cavity optomechanics
Authors: Fischer R , McNally D P , Reetz C , Assumpção G G T , Knief T , Lin Y , Regal C A
Published: March 2019

We explore the prospects and benefits of combining the techniques of cavity optomechanics with efforts to image spins using magnetic resonance force microscopy (MRFM). In particular, we focus on a common mechanical resonator used in cavity optomechanics—high-stress stoichiometric silicon nitride (Si3N4) membranes. We present experimental work with a ‘trampoline’ membrane resonator that has a quality factor above 106 and an order of magnitude lower mass than a comparable standard membrane resonators. Such high-stress resonators are on a trajectory to reach 0.1

aN

/

Hz

force sensitivities at MHz frequencies by using techniques such as soft clamping and phononic-crystal control of acoustic radiation in combination with cryogenic cooling. We present a demonstration of force-detected electron spin resonance of an ensemble at room temperature using the trampoline resonators functionalized with a magnetic grain. We discuss prospects for combining such a resonator with an integrated Fabry–Perot cavity readout at cryogenic temperatures, and provide ideas for future impacts of membrane cavity optomechanical devices on MRFM of nuclear spins.
Equivariant Kazhdan-Lusztig polynomials of thagomizer matroids
Authors: Xie Matthew , Zhang Philip B.
Published: March 2019

The equivariant Kazhdan-Lusztig polynomial of a matroid was introduced by Gedeon, Proudfoot, and Young. Gedeon conjectured an explicit formula for the equivariant Kazhdan-Lusztig polynomials of thagomizer matroids with an action of symmetric groups. In this paper, we discover a new formula for these polynomials which is related to the equivariant Kazhdan-Lusztig polynomials of uniform matroids. Based on our new formula, we confirm Gedeon’s conjecture by the Pieri rule.
Inequalities between Dirichlet and Neumann eigenvalues of the polyharmonic operators
Authors: Provenzano Luigi
Published: March 2019

We prove that

μ

k
+
m

m

>

λ
k
m

\mu _{k+m}^m >\lambda _k^m

, where

μ
k
m

\mu _k^m

(

λ
k
m

\lambda _k^m

) are the eigenvalues of

(
−
Δ

)
m

(-\Delta )^m

on

Ω
⊂

R

d

\Omega \subset \mathbb R^d

,

d
≥
2

d\geq 2

, with Neumann (Dirichlet) boundary conditions.
Entropy productions in dissipative systems
Authors: Qian Hong , Wang Shirou , Yi Yingfei
Published: March 2019

The present study aims to find connections between two types of entropy production rates for continuous dynamical systems, one defined in the general dissipation context and the other one defined in a thermodynamics context. On one hand, the entropy production rate

e
p

e_p

introduced by Andrey and Ruelle in the general dynamics context is based on Shannon’s entropy in the phase space that characterizes volume contraction relating to dissipation. On the other hand, the Helmholtz-Boltzmann entropy production rate

Q
˙

/

T

\dot {Q}/T

introduced in the context of mechanical theory of thermodynamics, where

Q
˙

\dot {Q}

is the rate of heat generations and

T
T

is the temperature, captures the thermodynamic entropy production relating to the mechanical energy dissipation. For certain cases of energy dissipative systems, we show that

e
p

e_p

is indeed related to

Q
˙

/

T

\dot {Q}/T

. This consistency between the general mathematical notion of dissipation and the thermodynamic entropy production in dissipative systems suggests a unifying representation of nonequilibrium phenomenon in deterministic systems based on the theory of nonlinear dynamical systems.
𝐾-theory for generalized Lamplighter groups
Authors: Li Xin
Published: March 2019

We compute

K
K

-theory for the reduced group C*-algebras of generalized Lamplighter groups.
Hopf-Galois structures of isomorphic-type on a non-abelian characteristically simple extension
Authors: Tsang Cindy
Published: March 2019

Let

L

/

K

L/K

be a finite Galois extension whose Galois group

G
G

is non-abelian and characteristically simple. By drawing tools from graph theory and group theory, we shall give a closed formula for the total number of Hopf-Galois structures on

L

/

K

L/K

with associated group isomorphic to

G
G

.