bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical Composition of Cacti Wood and Comparison with the Wood of Other Taxonomic Groups
Authors: Maceda Agustín , Soto‐Hernández Marcos , Peña‐Valdivia Cecilia B. , Terrazas Teresa 
Published: February 2018

The aims of this study were to determine the wood chemical composition of 25 species of Cactaceae and to relate the composition to their anatomical diversity. The hypothesis was that wood chemical components differ in relationship to their wood features. The results showed significant differences in wood chemical compounds across species and genera (P < 0.05). Pereskia had the highest percentage of lignin, whereas species of Coryphantha had the lowest; extractive compounds in water were highest for Echinocereus, Mammillaria, and Opuntia. Principal component analysis showed that lignin proportion separated the fibrous, dimorphic, and non‐fibrous groups; additionally, the differences within each type of wood occurred because of the lignification of the vascular tissue and the type of wall thickening. Compared with other groups of species, the Cactaceae species with fibrous and dimorphic wood had a higher lignin percentage than did gymnosperms and Acer species. Lignin may confer special rigidity to tracheary elements to withstand desiccation without damage during adverse climatic conditions.
ERK1/2 and Akt phosphorylation were essential for MGF E peptide regulating cell morphology and mobility but not proangiogenic capacity of BMSCs under severe hypoxia
Authors: Sha Yongqiang , Yang Li , Lv Yonggang 
Published: February 2018

Severe hypoxia inhibits the adhesion and mobility of bone marrow‐derived mesenchymal stem cells (BMSCs) and limits their application in bone tissue engineering. In this study, CoCl2 was used to simulate severe hypoxia and the effects of mechano‐growth factor (MGF) E peptide on the morphology, adhesion, migration, and proangiogenic capacity of BMSCs under hypoxia were measured. It was demonstrated that severe hypoxia (500‐μM CoCl2) significantly caused cell contraction and reduced cell area, roundness, adhesion, and migration of BMSCs. RhoA and ROCK1 expression levels were upregulated by severe hypoxia, but p‐RhoA and mobility‐relevant protein (integrin β1, p‐FAK and fibronectin) expression levels in BMSCs were inhibited. Fortunately, MGF E peptide could restore all abovementioned indexes except RhoA expression. MEK‐ERK1/2 pathway was involved in MGF E peptide regulating cell morphological changes, mobility, and relevant proteins (except p‐FAK). PI3K‐Akt pathway was involved in MGF E peptide regulating cell area, mobility, and relevant proteins. Besides, severe hypoxia upregulated vascular endothelial growth factor α expression but was harmful for proangiogenic capacity of BMSCs. Our study suggested that MGF E peptide might be helpful for the clinical application of tissue engineering strategy in bone defect repair.Significance of the studySever hypoxia impairs bone defect repair with bone marrow‐derived mesenchymal stem cells (BMSCs). This study proved that mechano‐growth factor E (MGF E) peptide could improve the severe hypoxia‐induced cell contraction and decline of cell adhesion and migration of BMSCs. Besides, MGF E peptide weakened the effects of severe hypoxia on the cytoskeleton arrangement‐ and mobility‐relevant protein expression levels in BMSCs. The underlying molecular mechanism was also verified. Finally, it was confirmed that MGF E peptide showed an adverse effect on the expression level of vascular endothelial growth factor α in BMSCs under severe hypoxia but could make up for this deficiency through accelerating cell proliferation.
Optogenetic Control by Pulsed Illumination
Authors: Hennemann Julia , Iwasaki Roman S. , Grund Tamara N. , Diensthuber Ralph P. , Richter Florian , Möglich Andreas 
Published: February 2018

AbstractSensory photoreceptors evoke numerous adaptive responses in nature and serve as light‐gated actuators in optogenetics to enable the spatiotemporally precise, reversible, and noninvasive control of cellular events. The output of optogenetic circuits can often be dialed in by varying illumination quality, quantity, and duration. A programmable matrix of light‐emitting diodes has been devised to efficiently probe the response of optogenetic systems to intermittently applied light of varying intensity and pulse frequency. Circuits for light‐regulated gene expression markedly differed in their responses to pulsed illumination of a single color which sufficed for their sequential triggering. In addition to quantity and quality, the pulse frequency of intermittent light hence provides a further input variable for output control in optogenetics and photobiology. Pulsed illumination schemes allow the reduction of overall light dose and facilitate the multiplexing of several lightdependent actuators and reporters.
Uniform experimental design in chemometrics
Authors: Xu Qing‐Song , Xu Yuan‐Da , Li Lan , Fang Kai‐Tai 
Published: February 2018

AbstractExperimental designs and modeling are very important in chemometrics and chemical engineering. There are many kinds of experimental designs, which include the fractional factorial design (including the orthogonal design), the optimal regression design, and the uniform design. The uniform experimental design can be regarded as a fractional factorial design with model uncertainty, a space filling design for computer experiments, a robust design against model specification, and a supersaturated design. This paper gives a brief introduction to the recent theoretical developments on uniform experimental design as well as its applications in chemometrics.
Augmenting Photoinduced Charge Transport in a Single‐Component Gel System: Controlled In Situ Gel–Crystal Transformation at Room Temperature
Authors: Satapathy Sitakanta , Prabakaran Palani , Prasad Edamana 
Published: February 2018

AbstractSmart single‐component materials with versatile functions require pre‐programming of a higher order molecular assembly. An electroactive supergelator (c=0.07 wt %) triphenylamine core‐appended poly(aryl ether) dendron (TPAPAE) is described, where substantial dendritic effects improve the order and crystallinity by switching the local minima from self‐assembled molecular wires to thermodynamically favorable global minima of ordered crystals, ripened within the fibers. Controlled in situ phase change at room temperature ultimately stabilized the mixed valence states in the single‐component supramolecular assembly with photoluminescence and photoinduced charge transport amplified by two orders of magnitude.
Enhanced Drug Photosafety by Interchromophoric Interaction Owing to Intramolecular Charge Separation
Authors: Li Ming‐De , Yan Zhiping , Zhu Ruixue , Phillips David Lee , Aparici‐Espert Isabel , Lhiaubet‐Vallet Virginie , Miranda Miguel A. 
Published: February 2018

AbstractImatinib is a synthetic tyrosinase inhibitor that is employed for the treatment of some kinds of human cancer. This drug has a low phototoxicity towards DNA, but its pyridylpyrimidine (1) fragment by itself exhibits significant phototoxicitiy. The intrinsic mechanism that leads to the enhanced photosafety of Imatinib is not yet known. Here, the properties of the excited state and interchromophoric interactions of Imatinib have been explored by using ultrafast laser flash photolysis and agarose electrophoresis studies. An intramolecular charge separation was directly observed for the irradiated Imatinib, which accounts for the relaxation of its excited state. An anionic form of pyridylpyrimidine (1) was deduced from the results of time‐resolved resonance Raman spectra and by quenching experimental studies on compound 1 and diaminotoluene. In contrast, compound 1 efficiently transformed into triplet excited states with a long lifetime, which explained the phototoxicity associated with this fragment. This work provides insight into how to design drugs with lower phototoxicitiy or improved photostability by using interchromophoric interactions.
Electronic circular dichroism for the detection of microalbuminuria
Authors: Habartová Lucie , Logerová Hana , Tomaník Lukáš , Marešová Aneta , Setnička Vladimír 
Published: February 2018

AbstractOver the past decades, chiroptical spectroscopy has proved its incomparable ability to elucidate the structure and spatial arrangement of chiral molecules. Systematic analysis of biomolecules in the natural environment of biofluids, however, remains challenging. In this study, we used chiroptical spectroscopy to monitor urinary levels of human serum albumin. Not only severe proteinuria but even just a slightly increased urinary excretion of albumin (microalbuminuria) may indicate serious health complications, especially for diabetic individuals. Given the chiral nature of albumin and its typical spectral pattern, it may be easily observable by chiroptical spectroscopy, particularly electronic circular dichroism. The performed chiroptical analysis of urine not only allowed the detection of clinically confirmed microalbuminuria but was also able to reveal this pathological condition in cases beyond the diagnostic capability of common clinical procedures. Thus, our approach suggests that electronic circular dichroism is a useful tool for the fast and reliable qualitative monitoring of microalbuminuria with the potential for a quantitative analysis in the future.
Synthesis, Characterization, and Biodistribution of a Dinuclear Gadolinium Complex with Improved Properties as a Blood Pool MRI Agent
Authors: La Cava Francesca , Fringuello Mingo Alberto , Miragoli Luigi , Terreno Enzo , Cappelletti Enrico , Lattuada Luciano , Poggi Luisa , Colombo Serra Sonia 
Published: February 2018

AbstractA dinuclear gadolinium(III) chelate containing two moieties of diethylenetriaminepentaacetic acid (DTPA), covalently conjugated to an analogue of deoxycholic acid, was synthesized and thoroughly characterized. A full relaxometric analysis was carried out, consisting of 1) the acquisition of nuclear magnetic resonance dispersion (NMRD) profiles in various media; 2) the study of binding affinity to serum albumin; 3) the measurement of 17O transverse relaxation rate versus temperature, and 4) a transmetallation assay. In vivo biodistribution MRI studies at 1 T and blood pharmacokinetics assays were carried out in comparison with Gd‐DTPA (Magnevist) and gadocoletic acid trisodium salt (B22956/1), two well‐known Gd complexes that share the same chelating cage and the same deoxycholic acid residue of the Gd complex investigated herein ((GdDTPA)2‐Chol). High affinity for plasma protein and, in particular, the availability of more than one binding site, allows the complex to reach a fairly high relaxivity value in plasma (∼20 mm−1 s−1, 20 MHz, 310 K) as well as to show unexpectedly enhanced properties of blood pooling, with an elimination half‐life in rats approximately seven times longer than that of B22956/1.
Use of the TCNQF42− Dianion in the Spontaneous Redox Formation of [FeIII(L−)2][TCNQF4⋅−]
Authors: Gass Ian A. , Lu Jinzhen , Asadi Mousa , Lupton David W. , Forsyth Craig M. , Geoghegan Blaise L. , Moubaraki Boujemaa , Cashion John D. , Martin Lisandra L. , Bond Alan M. , Murray Keith S. 
Published: February 2018

AbstractThe reaction of [FeII(L.)2](BF4)2 with Li2TCNQF4 results in the formation of [FeIII(L−)2][TCNQF4.−] (1) where L. is the radical ligand, 4,4‐dimethyl‐2,2‐di(2‐pyridyl)oxazolidine‐N‐oxide and TCNQF4 is 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane. This has been characterised by X‐ray diffraction, Raman and Fourier transform infrared (FTIR) spectroscopy, variable‐temperature magnetic susceptibility, Mössbauer spectroscopy and electrochemistry. X‐ray diffraction studies, magnetic susceptibility measurements and Raman and FTIR spectroscopy suggest the presence of low‐spin FeIII ions, the anionic form (L−) of the ligand and the anionic radical form of TCNQF4; viz. TCNQF4.−. Li2TCNQF4 reduces the [FeII(L.)2]2+ dication, which undergoes a reductively induced oxidation to form the [FeIII(L−)2]+ monocation resulting in the formation of [FeIII(L−)2][TCNQF4.−] (1), the electrochemistry of which revealed four well‐separated, diffusion‐controlled, one‐electron, reversible processes. Mössbauer spectroscopy and electrochemical measurements suggest the presence of a minor second species, likely to be [FeII(L.)2][TCNQF42−].
Tunable Bifunctional Activity of MnxCo3−xO4 Nanocrystals Decorated on Carbon Nanotubes for Oxygen Electrocatalysis
Authors: Zhao Tingting , Gadipelli Srinivas , He Guanjie , Ward Matthew J. , Do David , Zhang Peng , Guo Zhengxiao 
Published: February 2018

AbstractNoble‐metal‐free electrocatalysts are attractive for cathodic oxygen catalysis in alkaline membrane fuel cells, metal–air batteries, and electrolyzers. However, much of the structure–activity relationship is poorly understood. Herein, the comprehensive development of manganese cobalt oxide/nitrogen‐doped multiwalled carbon nanotube hybrids (MnxCo3−xO4@NCNTs) is reported for highly reversible oxygen reduction and evolution reactions (ORR and OER, respectively). The hybrid structures are rationally designed by fine control of surface chemistry and synthesis conditions, including tuning of functional groups at surfaces, congruent growth of nanocrystals with controllable phases and particle sizes, and ensuring strong coupling across catalyst–support interfaces. Electrochemical tests reveal distinctly different oxygen catalytic activities among the hybrids, MnxCo3−xO4@NCNTs. Nanocrystalline MnCo2O4@NCNTs (MCO@NCNTs) hybrids show superior ORR activity, with a favorable potential to reach 3 mA cm−2 and a high current density response, equivalent to that of the commercial Pt/C standard. Moreover, the hybrid structure exhibits tunable and durable catalytic activities for both ORR and OER, with a lowest overall potential of 0.93 V. It is clear that the long‐term electrochemical activities can be ensured by rational design of hybrid structures from the nanoscale.
Maternal care‐related differences in males and females rats’ sensitivity to ethanol and the associations between the GABAergic system and steroids in males
Authors: Popoola Daniel O. , Cameron Nicole M. 
Published: February 2018

AbstractThis study investigated the effect of maternal care on adolescent ethanol consumption, sensitivity to ethanol‐induced hypnosis, as well as gonadal hormones and γ‐aminobutyric acid type‐A (GABAA) systems. Long Evans rat dams were categorized by maternal licking/grooming (LG) frequency into High‐ and Low‐LG mothers. Both female and male offspring from Low‐LG rats demonstrated a greater sensitivity to ethanol‐induced hypnosis in the loss‐of‐righting‐reflex test at ethanol doses of 3.0 and 3.5 g/kg during late‐adolescence (postnatal Day 50) but not at mid‐adolescence (postnatal Day 42). However, we found no effect of maternal care on consumption of a 5% ethanol solution in a two‐bottle choice test. We further investigated the association between the observed variations in sensitivity to ethanol‐induced hypnosis and baseline hormonal levels in males. In male offspring from Low‐LG mothers compared to High‐LG mothers, baseline plasma corticosterone and progesterone levels were higher. GABAA α1 and δ subunit expressions were also higher in the cerebral cortex of Low‐LG males but lower in the cerebellar synaptosomal fraction. Early environmental influences on adolescent sensitivity to ethanol‐induced hypnosis, consumption, and preference may be mediated by gonadal hormones and possibly through GABAergic functions.
Responsiveness of rat fetuses to sibling motor activity: Communication in utero?
Authors: Brumley Michele R. , Hoagland Riana , Truong Melissa , Robinson Scott R. 
Published: February 2018

AbstractPrevious research has revealed that fetuses detect and respond to extrauterine stimuli such as maternal movement and speech, but little attention has been cast on how fetuses may directly influence and respond to each other in the womb. This study investigated whether motor activity of E20 rat fetuses influenced the behavior of siblings in utero. Three experiments showed that; (a) contiguous siblings expressed a higher frequency of synchronized movement than noncontiguous siblings; (b) fetuses that lay between two siblings immobilized with curare showed less movement relative to fetuses between saline or uninjected controls; and (c) fetuses between two siblings behaviorally activated by the opioid agonist U50,488 also showed less activity and specific behavioral changes compared to controls. Our findings suggest that rat fetuses are directly impacted by sibling motor activity, and thus that a rudimentary form of communication between siblings may influence the development of fetuses in utero.
A conservation planning tool for Greater Sage‐grouse using indices of species distribution, resilience, and resistance
Authors: Ricca Mark A. , Coates Peter S. , Gustafson K. Benjamin , Brussee Brianne E. , Chambers Jeanne C. , Espinosa Shawn P. , Gardner Scott C. , Lisius Sherri , Ziegler Pilar , Delehanty David J. , Casazza Michael L. 
Published: February 2018

AbstractManagers require quantitative yet tractable tools that identify areas for restoration yielding effective benefits for targeted wildlife species and the ecosystems they inhabit. As a contemporary example of high national significance for conservation, the persistence of Greater Sage‐grouse (Centrocercus urophasianus) in the Great Basin is compromised by strongly interacting stressors of conifer expansion, annual grass invasion, and more frequent wildfires occurring in sagebrush ecosystems. Associated restoration treatments to a sagebrush‐dominated state are often costly and may yield relatively little ecological benefit to sage‐grouse if implemented without estimating how Sage‐grouse may respond to treatments, or do not consider underlying processes influencing sagebrush ecosystem resilience to disturbance and resistance to invasive species. Here, we describe example applications of a spatially explicit conservation planning tool (CPT) to inform prioritization of: (1) removal of conifers (i.e., pinyon‐juniper); and (2) wildfire restoration aimed at improving habitat conditions for the Bi‐State Distinct Population Segment of Sage‐grouse along the California–Nevada state line. The CPT measures ecological benefits to sage‐grouse for a given management action through a composite index comprised of resource selection functions and estimates of abundance and space use. For pinyon‐juniper removal, we simulated changes in land‐cover composition following the removal of sparse trees with intact understories, and ranked treatments on the basis of changes in ecological benefits per dollar‐unit of cost. For wildfire restoration, we formulated a conditional model to simulate scenarios for land cover changes (e.g., sagebrush to annual grass) given estimated fire severity and underlying ecosystem processes influencing resilience to disturbance and resistance to invasion by annual grasses. For both applications, we compared CPT rankings to land cover changes along with sagebrush resistance and resilience metrics. Model results demonstrated how the CPT can be an important step in identifying management projects that yield the highest quantifiable benefit to Sage‐grouse while avoiding costly misallocation of resources, and highlight the importance of considering changes in sage‐grouse ecological response and factors influencing sagebrush ecosystem resilience to disturbance and resistance to invasion. This unique framework can be adopted to help inform other management questions aimed at improving habitat for other species across sagebrush and other ecosystems.
Studies of modern Italian dog populations reveal multiple patterns for domestic breed evolution
Authors: Talenti Andrea , Dreger Dayna L. , Frattini Stefano , Polli Michele , Marelli Stefano , Harris Alexander C. , Liotta Luigi , Cocco Raffaella , Hogan Andrew N. , Bigi Daniele , Caniglia Romolo , Parker Heidi G. , Pagnacco Giulio , Ostrander Elaine A. , Crepaldi Paola 
Published: February 2018

AbstractThrough thousands of years of breeding and strong human selection, the dog (Canis lupus familiaris) exists today within hundreds of closed populations throughout the world, each with defined phenotypes. A singular geographic region with broad diversity in dog breeds presents an interesting opportunity to observe potential mechanisms of breed formation. Italy claims 14 internationally recognized dog breeds, with numerous additional local varieties. To determine the relationship among Italian dog populations, we integrated genetic data from 263 dogs representing 23 closed dog populations from Italy, seven Apennine gray wolves, and an established dataset of 161 globally recognized dog breeds, applying multiple genetic methods to characterize the modes by which breeds are formed within a single geographic region. Our consideration of each of five genetic analyses reveals a series of development events that mirror historical modes of breed formation, but with variations unique to the codevelopment of early dog and human populations. Using 142,840 genome‐wide SNPs and a dataset of 1,609 canines, representing 182 breeds and 16 wild canids, we identified breed development routes for the Italian breeds that included divergence from common populations for a specific purpose, admixture of regional stock with that from other regions, and isolated selection of local stock with specific attributes.
The genomic and ecological context of hybridization affects the probability that symmetrical incompatibilities drive hybrid speciation
Authors: Comeault Aaron A. 
Published: February 2018

AbstractDespite examples of homoploid hybrid species, theoretical work describing when, where, and how we expect homoploid hybrid speciation to occur remains relatively rare. Here, I explore the probability of homoploid hybrid speciation due to “symmetrical incompatibilities” under different selective and genetic scenarios. Through simulation, I test how genetic architecture and selection acting on traits that do not themselves generate incompatibilities interact to affect the probability that hybrids evolve symmetrical incompatibilities with their parent species. Unsurprisingly, selection against admixture at “adaptive” loci that are linked to loci that generate incompatibilities tends to reduce the probability of evolving symmetrical incompatibilities. By contrast, selection that favors admixed genotypes at adaptive loci can promote the evolution of symmetrical incompatibilities. The magnitude of these outcomes is affected by the strength of selection, aspects of genetic architecture such as linkage relationships and the linear arrangement of loci along a chromosome, and the amount of hybridization following the formation of a hybrid zone. These results highlight how understanding the nature of selection, aspects of the genetics of traits affecting fitness, and the strength of reproductive isolation between hybridizing taxa can all be used to inform when we expect to observe homoploid hybrid speciation due to symmetrical incompatibilities.