bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advancements in the Search for Superhard Ultra‐Incompressible Metal Borides
Authors: Levine Jonathan B. , Tolbert Sarah H. , Kaner Richard B. 
Published: October 2009

AbstractDense transition metal borides have recently been identified as superhard materials that offer the possibility of ambient pressure synthesis compared to the conventional high pressure, high temperature approach. This feature article begins with a discussion of the relevant physical properties for this class of compounds, followed by a summary of the synthesis and properties of several transition metal borides. A strong emphasis is placed on correlating mechanical properties with electronic and atomic structure of these materials in an effort to better predict new superhard compounds. It concludes with a perspective of future research directions, highlighting some recent results and presenting several new ideas that remain to be tested.
A new recovery process of carbon dioxide from alkaline carbonate solution via electrodialysis
Authors: Nagasawa Hiroki , Yamasaki Akihiro , Iizuka Atsushi , Kumagai Kazukiyo , Yanagisawa Yukio 
Published: October 2009

AbstractBipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009
Alternative concept for SOFC with direct internal reforming operation: Benefits from inserting catalyst rod
Authors: Dokamaingam Pannipha , Laosiripojana Navadol , Soottitantawat Apinan , Assabumrungrat Suttichai 
Published: October 2009

AbstractMathematical models of direct internal reforming solid oxide fuel cell (DIR‐SOFC) fueled by methane are developed using COMSOL® software. The benefits of inserting Ni‐catalyst rod in the middle of tubular‐SOFC are simulated and compared to conventional DIR‐SOFC. It reveals that DIR‐SOFC with inserted catalyst provides smoother temperature gradient along the system and gains higher power density and electrochemical efficiency with less carbon deposition. Sensitivity analyses are performed. By increasing inlet fuel flow rate, the temperature gradient and power density improve, but less electrical efficiency with higher carbon deposition is predicted. The feed with low inlet steam/carbon ratio enhances good system performances but also results in high potential for carbon formation; this gains great benefit of DIR‐SOFC with inserted catalyst because the rate of carbon deposition is remarkably low. Compared between counter‐ and co‐flow patterns, the latter provides smoother temperature distribution with higher efficiency; thus, it is the better option for practical applications. © 2009 American Institute of Chemical Engineers AIChE J, 2010
Human birth seasonality and sunshine
Authors: Cummings David R. 
Published: October 2009

AbstractThe environmental light intensity/photoperiod (ELI/PP) hypothesis proposes that the seasonality of human births is primarily associated with seasonal changes in ambient atmospheric luminosity or ELI. This study tests for the presence of increased ELI during the 1 or 2‐month period preceding the conceptual month. Monthly birth data for Helsinki, Finland; Kiev, Ukraine; Hanoi, Vietnam; Matlab, Bangladesh; Nashville, Tennessee; Los Angeles, California; Dallas, Texas; Denver, Colorado and Pretoria, South Africa, are correlated (Pearsonian r) to corresponding monthly meteorological data. With the exception of Matlab, birth data are adjusted for conception date, 31‐day months, leap years and monthly deviation from an annual mean. Meteorological data are adjusted for a 1–2‐month exposure to ELI before conception. From these correlations, Helsinki r = 0.82, Kiev r = 0.80, Hanoi r = 0.93, Matlab r = 0.91, Nashville r = 0.84, Los Angeles r = 0.71, Dallas r = 0.86, Denver r = 0.53, and Pretoria r = −82. Weakness and strengths of the ELI/PP hypothesis are reviewed using the criteria developed by AB Hill. Substituting meteorological variables for ELI may be a weakness, whereas the specificity of ELI/PP predictions may be a strength. Increased periods of ELI precede increased periods of conceptions. Increased ELI may influence seasonality for chimpanzee, baboon, and humans. Atmospheric pollution may alter the onset of seasonality. Increased ELI may be the initial, but not the singular variable to affect seasonality. Am. J. Hum. Biol., 2010. © 2009 Wiley‐Liss, Inc.
Boys live dangerously in the womb
Authors: Eriksson Johan G. , Kajantie Eero , Osmond Clive , Thornburg Kent , Barker David J.P. 
Published: October 2009

AbstractThe growth of every human fetus is constrained by the limited capacity of the mother and placenta to deliver nutrients to it. At birth, boys tend to be longer than girls at any placental weight. Boy's placentas may therefore be more efficient than girls, but may have less reserve capacity. In the womb boys grow faster than girls and are therefore at greater risk of becoming undernourished. Fetal undernutrition leads to small size at birth and cardiovascular disorders, including hypertension, in later life. We studied 2003 men and women aged around 62 years who were born in Helsinki, Finland, of whom 644 had hypertension: we examined their body and placental size at birth. In both sexes, hypertension was associated with low birth weight. In men, hypertension was also associated with a long minor diameter of the placental surface. The dangerous growth strategy of boys may be compounded by the costs of compensatory placental enlargement in late gestation. In women, hypertension was associated with a small placental area, which may reduce nutrient delivery to the fetus. In men, hypertension was linked to the mothers' socioeconomic status, an indicator of their diets: in women it was linked to the mothers' heights, an indicator of their protein metabolism. Boys' greater dependence on their mothers' diets may enable them to capitalize on an improving food supply, but it makes them vulnerable to food shortages. The ultimate manifestation of their dangerous strategies may be that men have higher blood pressures and shorter lives than women. Am. J. Hum. Biol., 2010. © 2009 Wiley‐Liss, Inc.
Estimation of adult skeletal age‐at‐death using the Sugeno fuzzy integral
Authors: Anderson Melissa F. , Anderson Derek T. , Wescott Daniel J. 
Published: October 2009

AbstractAge‐at‐death estimation of an individual skeleton is important to forensic and biological anthropologists for identification and demographic analysis, but it has been shown that the current aging methods are often unreliable because of skeletal variation and taphonomic factors. Multifactorial methods have been shown to produce better results when determining age‐at‐death than single indicator methods. However, multifactorial methods are difficult to apply to single or poorly preserved skeletons, and they rarely provide the investigator with information about the reliability of the estimate. The goal of this research is to examine the validity of the Sugeno fuzzy integral as a multifactorial method for modeling age‐at‐death of an individual skeleton. This approach is novel because it produces an informed decision of age‐at‐death utilizing multiple age indicators while also taking into consideration the accuracies of the methods and the condition of the bone being examined. Additionally, the Sugeno fuzzy integral does not require the use of a population and it qualitatively produces easily interpreted graphical results. Examples are presented applying three commonly used aging methods on a known‐age skeletal sample from the Terry Anatomical Collection. This method produces results that are more accurate and with smaller intervals than single indicator methods. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.
Insect‐symbiont systems: From complex relationships to biotechnological applications
Authors: Chaves Sandra , Neto Marta , Tenreiro Rogério 
Published: October 2009

AbstractMicrobial symbiosis is a ubiquitous aspect of life and was a major element in the ability of insects to explore several adverse environments. To date, the study of symbiosis in insects has been impaired by the unculturability of most symbionts. However, some molecular methods represent powerful tools to help understand insect‐microorganism associations and to disclose new symbiont‐host systems. Beyond playing an essential role in nutrition and development of the insects, symbionts can produce bioactive compounds that protect the host against adverse environmental conditions, predators and/or direct competitors. Since the search for natural bioactive products and new enzymes is a developing area, understanding the diversity and nature of symbiont‐host relationships paves the way for the exploitation of new resources in biotechnology. Furthermore, genetic transformation of the symbionts with genes that code for compounds that are toxic for pathogenic and phytopathogenic agents is also a promising area of application of the insect‐symbiont relationships. The search for new bioactive compounds, the use of symbionts for pest and disease control and the molecular strategies applied for these purposes are issues of particular interest for innovative biotechnological applications and are addressed in the present review.
Recent trends in non‐viral vector‐mediated gene delivery
Authors: Pathak Atul , Patnaik Soma , Gupta Kailash Chand 
Published: October 2009

AbstractNucleic acids‐based next generation biopharmaceuticals (i.e., pDNA, oligonucleotides, short interfering RNA) are potential pioneering materials to cope with various incurable diseases. However, several biological barriers present a challenge for efficient gene delivery. On the other hand, developments in nanotechnology now offer numerous non‐viral vectors that have been fabricated and found capable of transmitting the biopharmaceuticals into the cell and even into specific subcellular compartments like mitochondria. This overview illustrates cellular barriers and current status of non‐viral gene vectors, i.e., lipoplexes, liposomes, polyplexes, and nanoparticles, to relocate therapeutic DNA‐based nanomedicine into the target cell. Despite the awesome impact of physical methods (i.e., ultrasound, electroporation), chemical methods have been shown to accomplish high‐level and safe transgene expression. Further comprehension of barriers and the mechanism of cellular uptake will facilitate development of nucleic acids‐based nanotherapy for alleviation of various disorders.
Experimental and Theoretical Study of Tunable 1,3‐Lithium Shift of Propargylic/Allenylic Species, Transmetallation, and Pd‐Catalyzed Cross‐Coupling Reactions
Authors: Zhao Jinbo , Liu Yu , He Qiwen , Li Yuxue , Ma Shengming 
Published: October 2009

AbstractThe highly selective tuning of the isomerization from 1‐arylalka‐1,2‐dien‐1‐yllithium to 1‐arylalka‐1,2‐dien‐3‐yllithium has been realized in the deprotonation of 1‐arylalk‐1‐yne (conditions A and B) and carbolithiation of 1‐arylbut‐3‐en‐1‐yne with alkyllithium (conditions C and D). Subsequent transmetallation and Pd‐catalyzed Negishi coupling reactions afforded 1,1‐diaryl or 1,3‐diaryl allenes with high selectivity. Deuterium‐labeling cross experiments indicated that an intermolecular lithiation process occurred in both 1,3‐lithium shift conditions (conditions B and D). 1‐Arylalka‐1,2‐diene was confirmed experimentally to be the intermediate. A computational study at the B3LYP level for the isomerization indicated that the acidity of H at the 3‐position is higher than that of the H at the 1‐position of 1‐phenyl‐1,2‐butadiene. Under conditions B, iPr2NH acts as a proton carrier to finish the 1,3‐lithium shift. The overall activation barrier for the rate‐determining step in the solvated models is ≈21.0 kcal mol−1, indicating that the isomerization is reasonable at room temperature. For the isomerization under conditions D, DFT calculations indicated that the addition of TMEDA (tetramethylethylenediamine) and HMPA (hexamethylphosphoramide) changes the global minimum of the system; among the possible mechanisms (P1–P5) considered, the mechanism catalyzed by dilithiated species (P5) is the most probable one. The overall activation barriers for isomerization in THF and TMEDA solvated models are 22.6 and 19.7 kcal mol−1, respectively, proving that the isomerization may proceed at RT in THF or at −78 °C with TMEDA, due to the fact that the solvation of the additives may increase the concentration of 1‐phenyl‐1,2‐butadienyllithium monomer by a deaggregation effect.
Light‐Driven Charge Separation in Isoxazolidine–Perylene Bisimide Dyads
Authors: Langhals Heinz , Obermeier Andreas , Floredo Yvonne , Zanelli Alberto , Flamigni Lucia 
Published: October 2009

AbstractA series of arrays for light‐driven charge separation is presented, in which perylene tetracarboxylic bisimide is the light‐absorbing chromophore and electron acceptor, whereas isoxazolidines are colourless electron donors, the electron‐releasing properties of which are increased with respect to the amino group by means of the α‐effect. Charge separation (CS) in toluene over a distance ranging from ≈10 to ≈16 Å, with efficiencies of ≈95 to ≈50 % and CS lifetimes from 300 ps to 15 ns, are demonstrated. In dichloromethane the charge recombination reaction is faster than charge separation, preventing accumulation of the CS state. The effects of solvent polarity and molecular structure are discussed in the frame of current theories.
A Flexible Approach to Grandisine Alkaloids: Total Synthesis of Grandisines B, D, and F
Authors: Kurasaki Haruaki , Okamoto Iwao , Morita Nobuyoshi , Tamura Osamu 
Published: October 2009

AbstractThis article describes in detail the first total synthesis of grandisine alkaloids, grandisines B, D, and F, which show affinity for the human δ‐opioid receptor. The key steps in this synthesis are construction of the isoquinuclidinone moiety of 2 by intramolecular imine formation and the tetracyclic ring system of 4 by stereoselective ring closure of the enolate of amine 8 generated by 1,4‐addition of ammonia to 9. Synthesis of key intermediate 9 featured a highly stereoselective Brønsted acid mediated Morita–Baylis–Hillman (MBH) reaction via the N‐acyl iminium ion.
Role of Environmental Factors on the Structure and Spectroscopic Response of 5′‐DNA–Porphyrin Conjugates Caused by Changes in the Porphyrin–Porphyrin Interactions
Authors: Mammana Angela , Pescitelli Gennaro , Asakawa Tomohiro , Jockusch Steffen , Petrovic Ana G. , Monaco Regina R. , Purrello Roberto , Turro Nicholas J. , Nakanishi Koji , Ellestad George A. , Balaz Milan , Berova Nina 
Published: October 2009

AbstractWe have explored the utility, strength, and limitation of through‐space exciton‐coupled circular dichroism in determination of the secondary structure of optically active chromophoric nanoarrays using the example of end‐capped porphyrin– and metalloporphyrin–oligodeoxynucleotide conjugates. We put special emphasis on the explanation of the origin and significance of the distinctive multiple bands in the CD spectra (trisignate and tetrasignate CD bands). Such CD profiles are often observed in chiral aggregates or multichromophoric arrays but have never before been studied in detail. We found that variation of temperature and ionic strength has a profound effect on the geometry of the porphyrin–DNA conjugates and thus the nature of electronic interactions. At lower temperatures and in the absence of NaCl all three 5′‐DNA–porphyrin conjugates display negative bisignate CD exciton couplets of variable intensity in the Soret region resulting from through‐space interaction between the electric transition dipole moments of the two end‐capped porphyrins. As the temperature is raised these exciton couplets are transformed into single positive bands originating from the porphyrin–single‐strand DNA interactions. At higher ionic strengths and low temperatures, multisignate CD bands are observed in the porphyrin Soret region. These CD signature bands originate from a combination of intermolecular, end‐to‐end porphyrin–porphyrin stacking between duplexes and porphyrin–DNA interactions. The intermolecular aggregation was confirmed by fluorescence and absorption spectroscopy and resonance light scattering. DeVoe theoretical CD calculations, in conjunction with molecular dynamics simulations and Monte Carlo conformational searches, were used to mimic the observed bisignate exciton‐coupled CD spectra as well as multiple CD bands. Calculations correctly predicted the sign and shape of the experimentally observed CD spectra. These studies reveal that the exciton‐coupled circular dichroism is a very useful technique for the determination of the structure of optically active arrays.
Interaction of Artemisinins with Oxyhemoglobin Hb–FeII, Hb–FeII, CarboxyHb–FeII, Heme–FeII, and Carboxyheme FeII: Significance for Mode of Action and Implications for Therapy of Cerebral Malaria
Authors: Coghi Paolo , Basilico Nicoletta , Taramelli Donatella , Chan Wing‐Chi , Haynes Richard K. , Monti Diego 
Published: October 2009

AbstractIn line with the enhancement of antimalarial activities of the current clinical artemisinins against parasites cultured under CO, the artemisinins are unaffected in vitro by carboxyhemoglobin (CO–Hb–FeII) or CO–heme–FeII, but are competitively decomposed by Hb–FeII or heme–FeII. In the latter case, the heme studies are greatly facilitated by solubilization of the heme in aqueous medium by use of arginine. None of the Hb species has an appreciable effect on artemisone, or on other aminoartemisinins, and antimalarial activities are either less affected or remain essentially unchanged against parasites cultured under standard microaerophilic conditions or under CO. The findings not only indicate that artemisinins do not require Hb–FeII or heme–FeII for promotion of antimalarial activity, but are also important in relation to the therapy of severe/complicated or cerebral malaria.
Development and evaluation of gamut extension algorithms
Authors: Laird Justin , Muijs Remco , Kuang Jiangtao 
Published: October 2009

AbstractIn recent years, new display technologies have emerged that are capable of producing colors that exceed the color gamut of broadcast standards. On the other hand, most video content currently remains compliant with the EBU standard and as such, there is a need for color mapping algorithms that make optimal use of the wider gamut of these new displays. To identify appropriate color mapping strategies, we have developed, implemented, and evaluated several approaches to gamut extension. The color rendering performance and robustness to different image content of these algorithms were evaluated against a reference (true‐color) mapping. To this end, two psychophysical experiments were conducted using a simulated and actual wide‐gamut display. Results show that the preferred algorithm had a dependency on image content, especially for images with skin tones. In both experiments, however, there was preference shown for the algorithm that balances chroma and lightness modulations as a function of the input lightness. The newly designed extension algorithms consistently outperformed true‐color mapping, thus confirming the benefit of appropriate mapping on wide‐gamut displays. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 443–451, 2009
Superficial degradation evaluated through color change in weathered orange LLDPE
Authors: González‐Mota Rosario , Soto‐Bernal Juan J. , Rosales‐Candelas Iliana , Frausto‐Reyes Claudio , Vega‐Durán Jose T. 
Published: October 2009

AbstractWe report the evaluation of superficial degradation of orange and colorless linear low density polyethylene samples exposed to weather. Color change and UV–VIS absorption were measured on samples exposed to the weather conditions of the city of Aguascalientes, Mexico, for more than a year. The color change was calculated in CIELAB units. Color change and absorption presented an exponential decay with time for orange samples, whereas they remained constant for colorless samples. No degradation products from the polymer matrix were revealed by UV–VIS spectroscopy, and apart from color change, no other degradation was noticed. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 458–463, 2009
Recombination of Photogenerated Lophyl Radicals in Imidazolium‐Based Ionic Liquids
Authors: Strehmel Veronika , Wishart James F. , Polyansky Dmitry E. , Strehmel Bernd 
Published: October 2009

AbstractLaser flash photolysis is applied to study the recombination reaction of lophyl radicals in ionic liquids in comparison with dimethylsulfoxide as an example of a traditional organic solvent. The latter exhibits a similar micropolarity as the ionic liquids. The ionic liquids investigated are 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (1), 1‐hexyl‐3‐methylimidazolium hexafluorophosphate (2), and 1‐butyl‐3‐methylimidazolium tetafluoroborate (3). The recombination of the photolytic generated lophyl radicals occur significantly faster in the ionic liquids than expected from their macroscopic viscosities and is a specific effect of these ionic liquids. On the other hand, this reaction can be compared with the macroscopic viscosity in the case of dimethylsulfoxide. Activation parameters obtained for lophyl radical recombination suggest different, anion‐dependent mechanistic effects. Quantum chemical calculations based on density functional theory provide a deeper insight of the molecular properties of the lophyl radical and its precursor. Thus, excitation energies, spin densities, molar volumes, and partial charges are calculated. Calculations show a spread of spin density over the three carbon atoms of the imidazolyl moiety, while only low spin density is calculated for the nitrogens.
Image segmentation and dynamic lineage analysis in single‐cell fluorescence microscopy
Authors: Wang Quanli , Niemi Jarad , Tan Chee‐Meng , You Lingchong , West Mike 
Published: October 2009

AbstractAn increasingly common component of studies in synthetic and systems biology is analysis of dynamics of gene expression at the single‐cell level, a context that is heavily dependent on the use of time‐lapse movies. Extracting quantitative data on the single‐cell temporal dynamics from such movies remains a major challenge. Here, we describe novel methods for automating key steps in the analysis of single‐cell, fluorescent images—segmentation and lineage reconstruction—to recognize and track individual cells over time. The automated analysis iteratively combines a set of extended morphological methods for segmentation, and uses a neighborhood‐based scoring method for frame‐to‐frame lineage linking. Our studies with bacteria, budding yeast and human cells, demonstrate the portability and usability of these methods, whether using phase, bright field or fluorescent images. These examples also demonstrate the utility of our integrated approach in facilitating analyses of engineered and natural cellular networks in diverse settings. The automated methods are implemented in freely available, open‐source software. © 2009 International Society for Advancement of Cytometry