bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parental Care and Investment
Authors: Gonzalez‐Voyer Alejandro , Kolm Niclas 
Published: February 2010

Abstract

Parental care is common throughout the animal kingdom and among caring species there is a bewildering variation in how parents care for offspring, as well as in the amount of resources parents invest in care. For instance, there is considerable variation in the relative parental investment by the sexes – in some species females invest more, in others males invest more, and in some investment is more or less equally shared. Different hypotheses have been proposed to explain patterns of parental investment between the sexes, as well as among species, and work is still ongoing to develop an overarching hypothesis that can explain the various patterns observed.

Key concepts:

Among species there is ample variation in how parents care for their offspring, if at all, as well as in how much they invest in offspring.

Differences between the sexes in relative parental investment have been recently proposed to depend on sexual selection and the operational sex ratio, rather than sexual selection patterns resulting from relative parental investment by the sexes, as previously suggested.

Individual decisions on the optimal parental investment can lead to conflict between parents as well as between parents and the offspring.

In some species, care of the offspring is not the exclusive responsibility of the parents but is shared among members of a group, termed cooperative breeding. In other species, adults sometimes take care of unrelated offspring, either willingly (as in adoptions) or unwillingly (as in brood parasitism).

Within species, parents may adjust the amount of investment in offspring based on signals from their partner or from the offspring themselves.
Meiotic Sex Chromosome Inactivation
Authors: Daish Tasman J , Grützner Frank 
Published: February 2010

Abstract

The differentiation of sex chromosomes through evolution has resulted in significant loss of homology and gene content which has profound consequences on gene dosage between the sexes and impacts on their behaviour through meiosis. During spermatogenesis the unpaired DNA, of heteromorphic sex chromosomes becomes transcriptionally silenced and sequestered into a ‘sex body’, a process termed ‘meiotic sex chromosome inactivation’. This essential meiotic event involves an ordered hierarchy of epigenetic changes to the sex chromosome DNA initiated by conserved DNA damage, repair and checkpoint machinery. Although the reason for this repression remains unclear, it is thought to prevent recombination between nonhomologous sex chromosome DNA and to avoid stringent meiotic checkpoints. Recent work has extended our understanding of the evolutionary conservation of meiotic silencing to include the avian ZW sex chromosome system providing new insights into the evolutionary dynamics of meiotic sex chromosome organization in diverse species.

Key concepts:

The accumulation of mutation and rearrangements on sex chromosomes lead to blocks in recombination, accumulation of sexually antagonistic genes and the differential degradation of sex chromosomes.

Heteromorphic sex chromosomes result in gene dosage imbalance between the sexes and unsynapsed DNA in meiosis I.

Meiotic sex chromosome inactivation protects unpaired sex chromosome DNA from aberrant recombination and checkpoint surveillance machinery.

Sex chromosomes undergo transcriptional silencing during late prophase due to the accumulation of conserved epigenetic changes.

Therian mammals have active X‐borne retrogenes on autosomes to compensate for the loss of transcription of sex chromosome genes important for spermatogenesis.
Adhesion and Percolation Parameters in Two Dimensional Pd–LSCM Composites for SOFC Anode Current Collection
Authors: Boulfrad Samir , Cassidy Mark , Irvine John T. S. 
Published: February 2010

AbstractThis paper is concerned with palladium–(La0.75Sr0.25)0.97Cr0.5Mn0.5O3 (LSCM) composite current collectors for solid oxide fuel cells (SOFCs); the composites, which are in a 2D configuration (thickness of about 8–10 µm), are deposited upon an LSCM electrode layer on top of an yttria zirconia electrolyte substrate. The influence of the LSCM particle size on the adhesion between palladium and LSCM are reported and discussed. Compositions using four different LSCM particle sizes (0.21, 0.49, 0.64, and 0.81 µm) with sintered Pd particle sizes approaching 10 µm are investigated. The best bonding is obtained when smaller particles are used. The electrical dc conductivity of the composite is reported as a function of the palladium volume fraction for all used LSCM particle sizes. The measured experimental values present typical insulating–conductive percolation. However, the transition occurs at ∼33% of the conductive phase, that is, a lower percentage than for 2D ideal systems and a higher percentage than for 3D ideal systems. This is consistent with lower‐dimension percolation for a system of large‐grained conductors and small‐grained insulators. The general effective media (GEM) equation is used to fit the experimental data, and the two main parameters (the threshold point ϕc and the exponent t) are defined.
Characterization of a Novel Fiber Composite Material for Mechanotransduction Research of Fibrous Connective Tissues
Authors: Screen Hazel R. C. , Byers Scott R. , Lynn Aaron D. , Nguyen Vien , Patel Dharmesh , Bryant Stephanie J. 
Published: February 2010

AbstractMechanotransduction is the fundamental process by which cells detect and respond to their mechanical environment, and is critical for tissue homeostasis. Understanding mechanotransduction mechanisms will provide insights into disease processes and injuries, and may support novel tissue engineering research. Although there has been extensive research in mechanotransduction, many pathways remain unclear, due to the complexity of the signaling mechanisms and loading environments involved. This study describes the development of a novel hydrogel‐based fiber composite material for investigating mechanotransduction in fibrous tissues. By encapsulating poly(2‐hydroxyethyl methacrylate) rods in a bulk poly(ethylene glycol) matrix, it aims to create a micromechanical environment more representative of that seen in vivo.Results demonstrated that collagen‐coated rods enable localized cell attachment, and cells are successfully cultured for one week within the composite. Mechanical analysis of the composite indicates that gross mechanical properties and local strain environments could be manipulated by altering the fabrication process. Allowing diffusion between the rods and surrounding matrix creates an interpenetrating network whereby the relationships between shear and tension are altered. Increasing diffusion enhances the shear bond strength between rods and matrix and the levels of local tension along the rods. Preliminary investigation into fibroblast mechanotransduction illustrates that the fiber composite upregulates collagen I expression, the main protein in fibrous tissues, in response to cyclic tensile strains when compared to less complex 2D and 3D environments. In summary, the ability to create and manipulate a strain environment surrounding the fibers, where combined tensile and shear forces uniquely impact cell functions, is demonstrated.
Blutspuren. Zur Bedeutung des Blutes in der Kriminalwissenschaft um 1900
Authors: Bachhiesl Christian 
Published: February 2010

AbstractTraces of Blood. The Significance of Blood in Criminology at the Turn of the 19th Century. In late 19th and early 20th century, criminology became institutionalized as an independent branch of science. Methodologically it focused on the ‘exact’ methods of the natural sciences, but also it tried to integrate the methods of the humanities. This mix of methods becomes visible in the treatment of blood, which on the one hand was an object of then brand new methods of scientific analysis (identification of human blood by the biological or precipitin method), and on the other hand was analyzed as a product of the magic and superstitious mentalities of criminals. The methodical tension resulting from this epistemological cross‐breeding did not disturb the criminologists, for whom the reconciliation of opposite ways of thinking and researching seemed to be possible. In this encyclopaedic analysis of blood early criminology tried to combine the anthropological exploration of vampirism with the chemical and microscopic detection of antibodies and haemoglobin, thus mirroring the positivistic optimism that was then prevalent.
Directed Evolution of an Antitumor Drug (Arginine Deiminase PpADI) for Increased Activity at Physiological pH
Authors: Zhu Leilei , Tee Kang Lan , Roccatano Danilo , Sonmez Burcu , Ni Ye , Sun Zhi‐Hao , Schwaneberg Ulrich 
Published: February 2010

AbstractArginine deiminase (ADI; EC 3.5.3.6) has been studied as a potential antitumor drug for the treatment of arginine‐auxotrophic tumors, such as hepatocellular carcinomas (HCCs) and melanomas. Studies with human lymphatic leukemia cell lines confirmed that ADI is an antiangiogenic agent for treating leukemia. The main limitation of ADI from Pseudomonas plecoglossicida (PpADI) lies in its pH‐dependent activity profile, its pH optimum is at 6.5. A pH shift from 6.5 to 7.5 results in an approximately 80 % drop in activity. (The pH of human plasma is 7.35 to 7.45.) In order to shift the PpADI pH optimum, a directed‐evolution protocol based on an adapted citrulline‐screening protocol in microtiter‐plate format was developed and validated. A proof of concept for ADI engineering resulted in a pH optimum of pH 7.0 and increased resistance under physiological and slightly alkaline conditions. At pH 7.4, variant M2 (K5T/D44E/H404R) is four times faster than the wild‐type PpADI and retains ∼50 % of its activity relative to its pH optimum, compared to ∼10 % in the case of the wild‐type PpADI.
Amminelithium Amidoborane Li(NH3)NH2BH3: A New Coordination Compound with Favorable Dehydrogenation Characteristics
Authors: Xia Guanglin , Yu Xuebin , Guo Yanhui , Wu Zhu , Yang Chuanzhen , Liu Huangkun , Dou Shixue 
Published: February 2010

AbstractThe monoammoniate of lithium amidoborane, Li(NH3)NH2BH3, was synthesized by treatment of LiNH2BH3 with ammonia at room temperature. This compound exists in the amorphous state at room temperature, but at −20 °C crystallizes in the orthorhombic space group Pbca with lattice parameters of a=9.711(4), b=8.7027(5), c=7.1999(1) Å, and V=608.51 Å3. The thermal decomposition behavior of this compound under argon and under ammonia was investigated. Through a series of experiments we have demonstrated that Li(NH3)NH2BH3 is able to absorb/desorb ammonia reversibly at room temperature. In the temperature range of 40–70 °C, this compound showed favorable dehydrogenation characteristics. Specifically, under ammonia this material was able to release 3.0 equiv hydrogen (11.18 wt %) rapidly at 60 °C, which represents a significant advantage over LiNH2BH3. It has been found that the formation of the coordination bond between ammonia and Li+ in LiNH2BH3 plays a crucial role in promoting the combination of hydridic BH bonds and protic NH bonds, leading to dehydrogenation at low temperature.
Stereoselective Formation of Triphenylene Ketals
Authors: Boshta Nader M. , Bomkamp Martin , Schnakenburg Gregor , Waldvogel Siegfried R. 
Published: February 2010

AbstractThe oxidative trimerization of catechol ketals by MoCl5 or MoCl5/TiCl4 mixtures leads preferentially to the all‐syn stereoisomer of the corresponding triphenylene ketal. The concomitant metal salts of the oxidative coupling most probably form a multinuclear template that directs the diastereoselectivity in a subsequent isomerization step under electrophilic conditions. Several functionalities can serve as coordination sites for the multinuclear metal chloro clusters. Suitable functional groups have to be stable towards the strong electrophilic and oxidizing conditions. Therefore, esters, nitriles, nitro derivatives, triazoles, and pyridines are successfully employed. Based on the flexibility and size of the substrate, different reagent mixtures lead to the stereoselective formation of the all‐syn derivatives.
Metal Ion Extraction with Bipyridine Derivatives as Chelating Ligands in Supercritical Carbon Dioxide
Authors: Yang Hai‐Jian , Kim Hakwon , Guo Cun‐Yue 
Published: February 2010

AbstractThree fluorinated bipyridine ligands have been designed and synthesized as chelating agents for the extraction of metal ions in supercritical CO2 (sc‐CO2). The ligand solubilities in sc‐CO2 were investigated at different temperatures and pressures, and the measured data have been correlated using a semiempirical model. The calculated results showed satisfactory agreement with the experimental data. Based on these data, metal ion extraction with the three compounds as chelating agents in sc‐CO2 was performed from spiked filter paper, whereby ligand 1 showed the highest extraction efficiency, especially for Ni2+ and Cu2+. The extraction constants, Kex, of the three chelating ligands were seen to increase with increasing extraction efficiency for the same metal ion in the same extraction system.
A Structure‐Based Virtual Screening Approach toward the Discovery of Histone Deacetylase Inhibitors: Identification of Promising Zinc‐Chelating Groups
Authors: Park Hwangseo , Kim Sukyoung , Kim Yong Eun , Lim Soo‐Jeong 
Published: February 2010

AbstractThe inhibitors of histone deacetylases (HDACs) have drawn a great deal of attention due to their promising potential as small‐molecule therapeutics for the treatment of cancer. By means of virtual screening with docking simulations under consideration of the effects of ligand solvation, we were able to identify six novel HDAC inhibitors with IC50 values ranging from 1 to 100 μM. These newly identified inhibitors are structurally diverse and have various chelating groups for the active site zinc ion, including N‐[1,3,4]thiadiazol‐2‐yl sulfonamide, N‐thiazol‐2‐yl sulfonamide, and hydroxamic acid moieties. The former two groups are included in many drugs in current clinical use and have not yet been reported as HDAC inhibitors. Therefore, they can be considered as new inhibitor scaffolds for the development of anticancer drugs by structure–activity relationship studies to improve the inhibitory activities against HDACs. Interactions with the HDAC1 active site residues responsible for stabilizing these new inhibitors are addressed in detail.
Disturbances in the habitat of Macrocotyla glandulosa (Kenk)
Authors: Wicks Carol , Noltie Douglas B. , Peterson Eric W. , Dogwiler Toby 
Published: February 2010

AbstractDisturbances lead to the displacement or mortality of organisms or communities. In stream ecosystems, hydrologic disturbances (floods, spates, freshets) can dislodge organisms from the streambed habitat and in some cases dislodge the sediment itself (scour). The primary aim of this study was to characterize the relation between the scour and the magnitude of freshets through the sediment size distribution and the depth of water at numerous locations along a cave stream in the habitat of the imperilled Macrocotyla glandulosa (Kenk), the pink planarian. Our hypothesis is that areas of stable streambed sediment would serve as habitat, whereas areas of mobile streambed sediment would not serve as habitat. We have combined the use of a numerical model of a cave stream with the size distribution of streambed sediment to designate locations of streambed stability or instability. Using pink planaria census data collected since 1988, we have identified locations that the pink planaria occupy and locations where the pink planaria have not been found. Our results show that five locations along the cave stream that lacked scour corresponded with locations of pink planaria occurrence, that two locations that experienced scour correspond with locations where the pink planaria were not found and that one location experienced scour and planaria were found. Thus, there seems to be a relation between the stability of streambed sediment and the use of that sediment as habitat. Conservation efforts aimed at increasing the population of the imperilled pink planarian should account for the stability of the streambed sediment. Copyright © 2010 John Wiley & Sons, Ltd.
Transformative ecosystem change and ecohydrology: ushering in a new era for watershed management
Authors: Wilcox Bradford P. 
Published: February 2010

AbstractAs a result of human activities, forests and rangelands across the globe have undergone dramatic changes that have fundamentally altered ecosystem processes. Examples of these kinds of transformational changes include increasingly hot and extensive forest fires, die‐off over vast areas of forest from insect infestations, large‐scale encroachment of rangelands by woody plants and non‐native invasive plants, and desertification. These changes have accelerated in pace, scale and magnitude in recent decades and have the potential to alter water, energy, and biogeochemical cycles in important but not fully understood ways. The related disciplines of ecohydrology and watershed management are being shaped and transformed by the need to understand the ecohydrological consequences of transformative landscape change as well as the need to mitigate and manage for these changes. Copyright © 2010 John Wiley & Sons, Ltd.
Benzo[h]quinoline Pincer Ruthenium and Osmium Catalysts for Hydrogenation of Ketones
Authors: Baratta Walter , Fanfoni Lidia , Magnolia Santo , Siega Katia , Rigo Pierluigi 
Published: February 2010

AbstractChiral orthometalated osmium complexes [OsCl(CN′N)(PP)] {PP = (S,R)‐Josiphos type diphosphane} based on 2‐aminomethylbenzo[h]quinoline ligands (HCN′N) were prepared by reaction of [OsCl2(PPh3)3] with a Josiphos diphosphane and a HCN′N ligand in the presence of NEt3. Ruthenium and osmium complexes [MX(CN′N)(PP)] {M = Ru, Os; X = Cl, OCH(p‐C6H4F)2; PP = dppb, (S,R)‐Josiphos}, in the presence of KOtBu, efficiently catalyze the chemoselective hydrogenation (H2 = 5 atm) of aromatic and aliphatic ketones to secondary alcohols in methanol or methanol/ethanol mixtures, when a S/C ratio of 10000–50000 is used. With use of these chiral phosphanes, alkyl aryl ketones have been reduced with ee values up to 99 % and turnover frequencies (TOFs) up to 5.6 × 104 h–1.
The latest Permian mass extinction in the Alborz Mountains (North Iran)
Authors: Angiolini Lucia , Checconi Alessio , Gaetani Maurizio , Rettori Roberto 
Published: February 2010

AbstractThe Elikah River section in the Alborz Mountains (North Iran) is a fossiliferous, continuous, marine section spanning the Permian–Triassic (P–T) boundary interval. Sixty‐eight taxa of brachiopods, foraminifers and algae have been collected bed‐by‐bed from the topmost 36 m of the Nesen Formation and the basal 2 m of the Elikah Formation, across the P–T boundary that is located in the basal metre of the latter formation. Forty‐six of these taxa from 62 samples have been considered for statistical analyses to unravel the pattern of extinction. First, their range extensions have been determined, which should be added to the highest stratigraphic occurrence of each taxon to identify the extinction level within a certain confidence interval (95%). Then the pattern of the extinction has been analysed, plotting the stratigraphic abundance versus last occurrence below the extinction horizon. The resulting pattern is of a sudden extinction occurring 30 cm below the biostratigraphically defined base of the Triassic. The confidence interval (95%) for the mass extinction is 30 cm thick. As predicted by the ‘Signor–Lipps effect’, brachiopod last occurrences underestimate the time of extinction, as their abundance is below 15%. Therefore, also in North Iran located at equatorial palaeolatitudes along the southern shore of the Palaeotethys Ocean, the pattern of the latest Permian mass extinction is abrupt as observed in South China, in peri‐Gondwana and in the Southern Alps. One of the most plausible mechanisms of the latest Permian sudden mass extinction could have been the emissions of tholeiitic magmas (Siberian Traps), which could have caused greenhouse gases emission into the atmosphere and thus global warming and ozone depletion, triggering the crisis (Svensen et al. 2008). Copyright © 2010 John Wiley & Sons, Ltd.
Water content of the mantle xenoliths from Kimberley and implications for explaining textural variations in cratonic roots
Authors: Katayama Ikuo , Michibayashi Katsuyoshi , Terao Ryuji , Ando Jun‐Ichi , Komiya Tsuyoshi 
Published: February 2010

AbstractWater contents estimates based on infrared spectroscopy and deformation microstructures are used to constrain the origin of textural variations observed in mantle xenoliths from Kimberley, South Africa. Infrared spectra indicate water contents of 10–370 ppm (H2O by weight) in olivine, 20–370 ppm in orthopyroxene, up to 340 ppm in garnet and 30–550 ppm in clinopyroxene, although no systematic differences are detected among texturally distinct xenoliths (i.e. granular and sheared peridotites). In contrast, active slip systems in olivine, as inferred from tilt boundaries, are different between the granular and sheared peridotites; the former deformed via the [100](010) slip system, which is commonly active under hot, dry conditions, whereas the latter deformed via the [001](100) slip system, which is commonly activated in water‐rich environments. The discrepancy in water contents estimates based on infrared spectroscopy and deformation microstructures may reflect different stages of the evolution of water content: the present water contents, as analysed by infrared spectroscopy, may have been modified by the most recent events (e.g. eruption by kimberlite magma), whereas the water contents inferred from tilt boundaries may have resulted from the various deformation processes in the deep cratonic mantle. Accordingly, we suggest that the observed heterogeneity in water content within cratonic roots facilitates local deformation, and gives rise to the range of textures seen in cratonic mantle xenoliths. Copyright © 2010 John Wiley & Sons, Ltd.
A pilot randomized controlled trial of sleep therapy in Parkinson's disease: effect on patients and caregivers
Authors: Leroi Iracema , Baker Peter , Kehoe Pam , Daniel Emily , Byrne E Jane 
Published: February 2010

AbstractObjectiveBy means of a controlled trial, to investigate the efficacy, tolerability and feasibility of a multi‐component sleep therapy intervention versus basic sleep hygiene education in PD patients with sleep disturbances and their live‐in carers.MethodsPatient‐carer dyads were randomised to either of the two interventions. Quantitative measures of sleep, psychiatric and overall functioning were administered at baseline and two weeks after the intervention to patients and carers.ResultsSleep disturbances in the PD patients improved significantly in both the groups. Between group comparisons in both carers and patients revealed no significant differences on any outcome measures. The intervention was found to be well tolerated, feasible and could easily be translated into the clinical setting.ConclusionsThis pilot study makes the case for further, more rigorous study of pragmatic, non‐pharmacological interventions for sleep disturbances in PD. Copyright © 2010 John Wiley & Sons, Ltd.