bluuebunny/crossref_metadata_2025 huggingface dataset:
The optical, physical and chemical properties of the products of glyoxal uptake on ammonium sulfate seed aerosols
Authors: Trainic M. , Abo Riziq A. , Lavi A. , Flores J. M. , Rudich Y.
Published: September 2011

Abstract. The heterogeneous reaction between gas phase glyoxal and ammonium sulfate (AS) aerosols, a proxy for inorganic atmospheric aerosol, was studied in terms of the dependence of the optical, physical and chemical properties of the product aerosols on initial particle size and ambient relative humidity (RH). Our experiments imitate an atmospheric scenario of a dry particle hydration at ambient RH conditions in the presence of glyoxal gas followed by efflorescence due to decrease of the ambient RH. The reactions were studied under different RH conditions, starting from dry conditions (~20% RH) and up to 90% RH, covering conditions prevalent in many atmospheric environments, and followed by consequent drying of the reacted particles before their analysis by the aerosol mass spectrometer (AMS), cavity ring down (CRD) and scanning mobility particle sizer (SMPS) systems. At λ = 355 nm, the reacted aerosols demonstrate a substantial growth in optical extinction cross section, as well as in mobility diameter under a broad range of RH values (35–90%). The ratio of the product aerosol to seed aerosol geometric cross section reached up to ~3.5, and the optical extinction cross-section up to ~250. The reactions show a trend of increasing physical and optical growth with decreasing seed aerosol size, from 100 nm to 300 nm, as well as with decreasing RH values from 90% to ~40%. Optically inactive aerosols, at the limit of the Mie range (100 nm diameter) become optically active as they grow due to the reaction. AMS analyses of the reaction of 300 nm AS at RH values of 50%, 75% and 90% show that the main products of the reaction are glyoxal oligomers, formed by acetal formation in the presence of AS. In addition, imidazole formation, which is a minor channel, is observed for all reactions, yielding a product which absorbs at λ = 290 nm, with possible implications on the radiative properties of the product aerosols. The ratio of absorbing substances (C-N compounds, including imidazoles) increases with increasing RH value. A core/shell model used for the investigation of the optical properties of the reaction products of AS with gas phase glyoxal, shows that the refractive index (RI) of the reaction products are n= 1.68(±0.10)+0.01(±0.02) at 50% RH and n = 1.65(±0.06)+0.02(±0.01) at 75% RH at 355 nm. The observed increase in the ratio of the absorbing substances is not indicated in the imaginary part of the products at RH 50% and 75%. A further increase in the ratio of absorbing substances and a resulting increase in the imaginary part of the RI at higher RH values is expected, and may become even more substantial after longer reaction times, possibly in cloud or fog droplets. This study shows that the reaction of abundant substances present in atmospheric aerosols, such as AS, and gas phase glyoxal alters the aerosols' optical, physical and chemical properties and may have implications on the radiative effect of these aerosols.
Distribution of ozone and its precursors over Bay of Bengal during winter 2009: role of meteorology
Authors: David L. M. , Girach I. A. , Nair P. R.
Published: September 2011

Abstract. Measurements of ozone and NO2 were carried out in the marine environment of the Bay of Bengal (BoB) during the winter months, December 2008–January 2009, as part of the second Integrated Campaign for Aerosols, gases and Radiation Budget conducted under the Geosphere Biosphere Programme of the Indian Space Research Organization. The ozone mixing ratio was found to be high in the head and the southeast BoB with a mean value of 61 ± 7 ppb and 53 ± 6 ppb, respectively. The mixing ratios of NO2 and CO were also relatively high in these regions. The spatial patterns were examined in the light of airflow patterns, air mass back trajectories and other meteorological conditions and satellite retrieved maps of tropospheric ozone, NO2, CO, and fire count in and around the region. The distribution of these gases was strongly associated with the transport from the adjoining land mass. The anthropogenic activities and forest fires/biomass burning over the Indo Gangetic Plains and other East Asian regions contribute to ozone and its precursors over the BoB. Similarity in the spatial pattern suggests that their source regions could be more or less the same. Most of the diurnal patterns showed decrease of the ozone mixing ratio during noon/afternoon followed by a nighttime increase and a morning high. Over this oceanic region, photochemical production of ozone involving NO2 was not very active. Water vapour played a major role in controlling the variation of ozone. An attempt is made to simulate ozone level over the north and south BoB using the photochemical box model (NCAR-MM). The present observed features were compared with those measured during the earlier cruises conducted in different seasons.
Annual screening strategies in BRCA1 and BRCA2 gene mutation carriers
Authors: Lowry Kathryn P. , Lee Janie M. , Kong Chung Y. , McMahon Pamela M. , Gilmore Michael E. , Cott Chubiz Jessica E. , Pisano Etta D. , Gatsonis Constantine , Ryan Paula D. , Ozanne Elissa M. , Gazelle G. Scott
Published: September 2011

BACKGROUND:

Although breast cancer screening with mammography and magnetic resonance imaging (MRI) is recommended for breast cancer‐susceptibility gene (BRCA) mutation carriers, there is no current consensus on the optimal screening regimen.

METHODS:

The authors used a computer simulation model to compare 6 annual screening strategies (film mammography [FM], digital mammography [DM], FM and magnetic resonance imaging [MRI] or DM and MRI contemporaneously, and alternating FM/MRI or DM/MRI at 6‐month intervals) beginning at ages 25 years, 30 years, 35 years, and 40 years, and 2 strategies of annual MRI with delayed alternating DM/FM versus clinical surveillance alone. Strategies were evaluated without and with mammography‐induced breast cancer risk using 2 models of excess relative risk. Input parameters were obtained from the medical literature, publicly available databases, and calibration.

RESULTS:

Without radiation risk effects, alternating DM/MRI starting at age 25 years provided the highest life expectancy (BRCA1, 72.52 years, BRCA2, 77.63 years). When radiation risk was included, a small proportion of diagnosed cancers was attributable to radiation exposure (BRCA1, <2%; BRCA2, <4%). With radiation risk, alternating DM/MRI at age 25 years or annual MRI at age 25 years/delayed alternating DM at age 30 years was the most effective, depending on the radiation risk model used. Alternating DM/MRI starting at age 25 years also produced the highest number of false‐positive screens per woman (BRCA1, 4.5 BRCA2, 8.1).

CONCLUSIONS:

Annual MRI at age 25 years/delayed alternating DM at age 30 years is probably the most effective screening strategy in BRCA mutation carriers. Screening benefits, associated risks, and personal acceptance of false‐positive results should be considered in choosing the optimal screening strategy for individual women. Cancer 2012. © 2011 American Cancer Society.
New challenges in the epidemiology and treatment of visceral leishmaniasis in periurban areas
Authors: Dupnik Kathryn M. , Nascimento Eliana L. , Rodrigues‐Neto Joao F. , Keesen Tatjana , Zélia Fernandes Maria , Duarte Iraci , Jeronimo Selma M.B.
Published: September 2011

Visceral leishmaniasis (VL) represents a major public health problem in many areas of the world. This review focuses on the impact of periurbanization on the epidemiology and treatment of VL, using Brazil as an example. VL continues to be primarily a disease of poverty with impact on families. However, the disease has expanded in Latin America, with foci reported as far south as Argentina. There is an increasing overlap of Leishmania infantum chagasi and human immune deficiency virus (HIV) infections and other immunosuppressive conditions, resulting in the emergence of VL as an opportunistic infection. This new setting poses new challenges for VL disease control and patient management. Drug Dev Res 72:451–462, 2011. © 2011 Wiley‐Liss, Inc.
Clinical aspects of Chagas disease and implications for novel therapies
Authors: Menezes Cristiane , Costa Germano Carneiro , Gollob Kenneth J. , Dutra Walderez O.
Published: September 2011

The interaction between the protozoan parasite Trypanosoma cruzi and the human host dates back 9,000 years, as demonstrated by molecular analysis of material obtained from Andean mummies indicating the presence of the parasite's kinetoplast DNA in populations from Chile and Peru. This long‐established interaction, which persists today, demonstrates that T. cruzi has established a very well adapted relationship with the human host. From the point of view of a host–parasite relationship, this is desirable; however, such a high degree of adaptation is perhaps the foundation for many of the unknowns that surround this disease. Unveiling of the immunological mechanisms that underlie the establishment of pathology, identification of parasite‐associated factors that determine strain‐differential tissue tropism, discovery of host genetic elements that influence the development of different clinical forms of the disease, and understanding environmental factors that may influence the host–parasite interactions are some of the key questions that remain to be answered. The response to these questions will aid in addressing some of the current challenges in Chagas disease: fulfilling the need for efficient diagnosis, developing effective prophylactic measures, discovering effective therapeutics, and finding methods to control disease progression. Drug Dev Res 72:471–479, 2011. © 2011 Wiley‐Liss, Inc.
Nanomolar Detection of Glutamate at a Biosensor Based on Screen‐Printed Electrodes Modified with Carbon Nanotubes
Authors: Khan Raju , Gorski Waldemar , Garcia Carlos D.
Published: September 2011

The flow injection analysis (FIA) of monosodium L‐glutamate (MSG) was performed electrochemically using a biosensor based on screen‐printed electrodes containing carbon nanotubes (CNT). The sensor was fabricated by simply adsorbing glutamate oxidase (GlutOx) on the electrode surface. The resulting device displayed excellent electroanalytical properties toward the determination of L‐glutamate in a wide linear range (0.01–10 µM) with low detection limit (10 nM, S/N≥3), fast response time (≤5 s), and good operational and long‐term stability. The CNT‐modified screen‐printed electrodes have a potential to be of general interest for easy preparation of electrochemical sensors and biosensors relevant for biomedical applications.
Denaturation of Drew–Dickerson DNA in a high salt concentration medium: Molecular dynamics simulations
Authors: Izanloo C. , Parsafar G. A. , Abroshan H. , Akbarzadeh H.
Published: September 2011

We have performed molecular dynamics simulation on B‐DNA duplex (CGCGAATTGCGC) at different temperatures. The DNA was immerged in a salt‐water medium with 1 M NaCl concentration to investigate salt effect on the denaturation process. At each temperature, configurational entropy is estimated using the covariance matrix of atom‐positional fluctuations, from which the melting temperature (Tm) was found to be 349 K. The calculated configuration entropy for different bases shows that the melting process involves more peeling (including fraying from the ends) conformations, and therefore the untwisting of the duplex and peeling states form the transition state of the denaturation process. There is a narrow minor groove in the AATT sequence that becomes wider by increasing temperature which disappears at high temperatures, especially above the melting temperature. We have also calculated the fraction of denatured base pairs, f‐curve, from which Tm was found to be 340 K, close to experimental value of 341 K. We found that DNA at high salt concentrations has few hydrogen bonds even at temperatures higher than the Tm. Our calculations show the fact that adding salt leads to increase of Tm and stabilization of DNA. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Echocardiographic abnormalities in a cohort of Chinese patients with systemic lupus erythematosus—a retrospective analysis of eighty‐five cases
Authors: Yu Xuan‐Hua , Li Yi‐Nong
Published: September 2011

Objective.

To investigate echocardiographic abnormalities in a cohort of Chinese patients with systemic lupus erythematosus (SLE).

Methods.

Eighty‐five SLE patients who were hospitalized at our institution from January 2008 to June 2009 were included. Their clinical manifestations, electrocardiogram, chest x‐ray, CT scan, and echocardiographic data were analyzed in relation to age, disease duration, and SLE disease activity index (SLEDAI).

Results.

Echocardiography showed abnormalities in 53 patients (62.35%), involving valves in 56.5% (n = 48), pericardium in 25.9%, left and right ventricle enlargement in 17.65% and 1.18%, respectively, and auricle in 10.59% and 1.18% of the patients, respectively. The left ventricle showed decreased compliance in 10.29%, impaired relaxation in 14.12%, and abnormal wall motion in 42.35% of the patients. Interventricular septum thickness, left ventricular posterior wall thickness, and isovolumic relaxation time were positively correlated with age (r = 0.42, 0.33, and 0.39, respectively, p < 0.01 for all variables), and disease duration (r = 0.22, 0.21, and 0.32, respectively; p < 0.05). Left atrial and ventricular size were correlated with age (r = 0.32 and 0.41, p > 0.01) and SLEDAI (p < 0.05).

Conclusions.

Cardiac, especially valvular abnormalities are common in SLE patients and increase with age and disease duration and activity. Inclusion of echocardiography in the clinical evaluation of SLE patients could help identify an important subset of patients with cardiac abnormalities. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011
Morphology and putative function of the colon and cloaca of marine and freshwater snakes
Authors: Babonis Leslie S. , Womack Molly C. , Evans David H.
Published: September 2011

Among tetrapods, evidence for postrenal modification of the urine by the distal digestive tract (including the colon and cloaca) is highly variable. Birds and bladderless reptiles are of interest because the colon and cloaca represent the only sites from which water and ions can be reclaimed from the urine secreted by the kidney. For animals occupying desiccating environments (e.g., deserts and marine environments), postrenal modification of the urine may directly contribute to the maintenance of hypo‐osmotic body fluids. We compared the morphology and distribution of key proteins in the colon, cloaca, and urogenital ducts of watersnakes from marine (Nerodia clarkii clarkii) and freshwater (Nerodia fasciata) habitats. Specifically, we examined the epithelia of each tissue for evidence of mucus production by examining the distribution of mucopolysaccharides, and for evidence of water/ion regulation by examining the distribution of Na+/K+‐ATPase (NKA), Na+/K+/Cl− cotransporter (NKCC), and aquaporin 3 (AQP3). NKCC localized to the basolateral epithelium of the colon, urodeal sphincter, and proctodeum, consistent with a role in secretion of Na+, Cl−, and K+ from the tissue, but NKA was not detected in the colon or any compartment of the cloaca. Interestingly, NKA was detected in the basolateral epithelium of the ureters, suggesting the urothelium may play a role in active ion transport. AQP3 was detected in the ureters and coprodeal complex, consistent with a role in urinary and fecal dehydration or, potentially, in the production of the watery component of the mucus secreted by the coprodeal complex. Since no differences in general cloacal morphology, production of mucus, or the distribution of ion transporters/water channels were detected between the two species, cloacal osmoregulation may either be regulated by proteins not examined in this study or may not be responsible for the differential success of N. c. clarkii and N. fasciata in marine habitats. J. Morphol. 2011. © 2011 Wiley Periodicals, Inc.
Water droplet spreading and recoiling upon contact with thick–compact maltodextrin agglomerates
Authors: Meraz‐Torres Lesvia Sofía , Quintanilla‐Carvajal María Ximena , Téllez‐Medina Darío I , Hernández‐Sánchez Humberto , Alamilla‐Beltrán Liliana , Gutiérrez‐López Gustavo F
Published: September 2011

BACKGROUND: The food and pharmaceutical industries handle a number of compounds in the form of agglomerates which must be put into contact with water for rehydration purposes. In this work, liquid‐solid interaction between water and maltodextrin thick–compact agglomerates was studied at different constituent particle sizes for two compression forces (75 and 225 MPa).

RESULTS: Rapid droplet spreading was observed which was similar in radius to the expected one for ideal, flat surfaces. Contact angle determinations reported oscillations of this parameter throughout the experiments, being indicative of droplet recoiling on top of the agglomerate. Recoiling was more frequent in samples obtained at 225 MPa for agglomerate formation. Agglomerates obtained at 75 MPa exhibited more penetration of the water. Competition between dissolution of maltodextrin and penetration of the water was, probably, the main mechanism involved in droplet recoiling. Micrographs of the wetting marks were characterized by means of image analysis and the measurements suggested more symmetry of the wetting mark at higher compression force.

CONCLUSION: Differences found in the evaluated parameters for agglomerates were mainly due to compaction force used. No significant effect of particle size in recoiling, penetration of water into the agglomerate, surface texture and symmetry was observed. Copyright © 2011 Society of Chemical Industry
Moore's law in photonics
Authors: Smit M. , van der Tol J. , Hill M.
Published: September 2011

A review of the complexity development of InP‐based Photonic ICs is given. Similarities and differences between photonic and microelectronic integration technology are discussed and a vision of the development of photonic integration in the coming decade is given.
Synthesis and Characterization of Poly(Dithieno[3,2‐b:2′,3′‐d]pyrrole) Derivatives Containing Thiophene Moieties and Their Application to Organic Devices
Authors: Jeong Hyung‐Gu , Lim Bogyu , Na Seok‐In , Baeg Kang‐Jun , Kim Juhwan , Yun Jin‐Mun , Kim Dong‐Yu
Published: September 2011

A series of conjugated polymers (PDTP, PDTPT, PDTPTT) based on dithieno[3,2‐b:2′,3′‐d]pyrrole (DTP) containing branched side‐chains is synthesized. The synthesized polymers show good solubility due to branched side‐chains in the organic solvent in the absence of heat treatment. To increase the oxidation potential, unsubstituted thiophene units are introduced into the polymer backbone. The introduction of unsubstituted thiophene units increases the oxidation potential, elevates degradation temperature, and enhances electronic properties. The PDTPTT FETs show the highest charge‐carrier mobility among the three polymers. These polymers are used as a donor material in bulk heterojunction solar cells, and the PDTPTT photovoltaic cells exhibit high performance.
Synthesis of Poly(2‐oxazoline)‐Based Hydrogels with Tailor‐Made Swelling Degrees Capable of Stimuli‐Triggered Compound Release
Authors: Kelly Andrew M. , Hecke Angela , Wirnsberger Bianca , Wiesbrock Frank
Published: September 2011

A 32‐membered library of poly(2‐oxazoline)‐based hydrogels of the composition pEtOxm‐pPhOxn‐pPBOq (m/n = 150/0, 100/50, 50/100, and 0/150; q = 1.5–30) was prepared from 2‐ethyl‐ (EtOx), 2‐phenyl‐2‐oxazoline (PhOx), and phenylene‐1,3‐bis‐(2‐oxazoline) (PBO). The polymerizations were performed from ground monomer mixtures at 140 °C in a single‐mode microwave reactor in reaction times as short as 1 h. Purified hydrogels, containing no residual monomers, were obtained in yields of 95% or higher. Acid‐mediated hydrolysis rates as well as swelling degrees of the hydrogels were adjustable over a broad range; swelling degrees in water/ethanol/dichloromethane ranged from 0 to 13.8/11.7/20.0. The hydrogels could incorporate organic molecules according to in situ or post‐synthetic routines. Post‐synthetic routines enabled for the preparation of hydrogels from which the incorporated compounds were only released through diffusion processes if the solvent was changed or through hydrogel degradation if the pH was lowered.
Thermal and acid labile polyurethanes as a new class of responsive materials in polymeric nanoparticles and nanocapsules
Authors: Siebert Joerg Max , Baier Grit , Landfester Katharina
Published: September 2011

A new class of polyurethanes has been designed, containing tertiary carbamate groups in the main chain of the polymer, which enable the resulting polymer to degrade completely under acid and thermal treatment. The decomposition temperatures of the polymers were determined by measuring the evolution of carbon dioxide and other decomposition products using TGA‐MS. Until decomposition of the polymer, no glass transition was found. The polymers exhibit excellent solubility in common organic solvents like chloroform and tetrahydrofuran, making them to suitable materials for film formation. From the obtained polymers, nanoparticles were synthesized by the solvent evaporation method combined with the miniemulsion technique. The resulting nanoparticles can be used as intelligent fillers in films and sensors, since they degrade at temperatures of above 180 °C, which can be detected by a color change reaction with ninhydrin. Polymeric nanocapsules were prepared by an interfacial polyaddition reaction from 2,4‐toluene diisocyanate and tertiary diols performed at the droplet's interface in inverse (water‐in‐oil) miniemulsions. These nanocapsules with an encapsulated photoacid generator can act as a release system, whereby an acidic release through irradiation with ultraviolet light can be triggered. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
PG 1237, Royal Cemetery of Ur: Patterns in Death
Authors: Vidale Massimo
Published: September 2011

This article discusses the identity of the people buried in the Great Death Pit PG 1237, a mass grave of the Royal Cemetery of Ur, and the ways they died and entered the shaft. Admittedly, the evidence required to positively solve the many taphonomic and osteological questions involved does not exist, because of the way the site was excavated and published in the early twentieth century. Nonetheless, the original excavators’ skill and unquestioned care in mapping and recording still prepares the ground for new alternative interpretations. As the ‘Rams Caught in a Thicket’ (two statuettes found in the mass grave) may have been the front parts of lyres, and almost all the dead might have entered the shaft impersonating musicians, singers and dancers, the paramount importance of music in the funerals of Sumerian elites is emphasized. New radiographic evidence recently suggested that some of the buried persons were killed violently, refuting the traditional theory of a voluntary mass suicide by poison. The bodies of the victims might have been formally prepared and serially brought to the pit in burial groups. Stratigraphy and spatial distribution reveal consistent depositional patterns dictated by specific rituals, as already proposed on the basis of more limited evidence by other authors. Formal arrangement and ritualism, in turn, support Woolley's identification of the graves as sacred constructions and thus reaffirms their royal character. The article ends by considering the historical meaning of the nature of these impressive funerals at the verge of the political unification of Mesopotamia by the house of Sargon.
Clinical orientation program for new medical registrars — a qualitative evaluation
Authors: Rosemergy Ian , Bell Damon A , Jayathissa Sisira K
Published: September 2011

We present a qualitative evaluation of a clinical
orientation program for medical registrars within the
Wellington region in New Zealand, designed and
implemented by current advanced registrars. This
program was intended to improve the transition
from house officer to medical registrar. The program
was qualitatively evaluated using focus
groups comprising participants, presenters and
senior nursing staff. Purposive samples were
drawn from each of these groups.
The most significant finding was the perception of
enhanced professional collegiality among medical
staff. There were benefits to participants and
presenters with improved communication between
medical registrars. We believe there are individual,
institutional and patient care benefits with a
region-specific, clinical orientation for new medical
registrars.
“A Lifetime”
Authors: Pirzad Zoya
Published: September 2011

It was very early in the morning. She was looking at the yard from behind a window. The tree was in full bloom. She removed a lock of white hair from her forehead. It was the forty-first time that she was watching the tree blossom. She was standing in front of the window in her thick white nightgown with long sleeves and closed collar. She was a bit cold. The wind made the blossoms shiver. It seemed that the flowers never felt cold. The woman recalled the very first time she watched them.

She has awakened to the sound of her husband's voice, “Wake up! Come and see! The tree has blossomed!” They have stood watching together at the window. Her long white nightgown was sleeveless and thin, with lace around its open collar. She wasn't cold, or perhaps it was her sense of decency that made her forget the cold.
The Ultimate Home: “A Home in the Sky”
Authors: Taraqqi Goli
Published: September 2011

Khatereha-ye parakandeh (scattered memoirs), from which “KhanehDi dar asman” (A Home in the Sky) has been selected and translated here, was the first original book of Goli Taraqqi (b. 1939) that appeared in Iran since the publication of her novel Khab-e zemestani (Winter Sleep) in 1973. (“Khaneh3i dar asman” itself had been published earlier in the November 1991 issue of the literary journal Kelk.) In 1979 Goli Taraqqi moved to France with her two sons and began a new phase of her literary career. A French translation of her short story “Bozorgbanu-ye ruh-e man” (The Great Lady of My Soul) won the Contre-Ciel literary award in 1985, and a year later, with her own cooperation, a French translation of Khab-e zemestani (Winter Sleep) was published in Paris.
Notes on Timurid Legitimacy in Three Safavid Chronicles
Authors: Quinn Sholeh A.
Published: September 2011

In his Study on Afsharid Historiography, Ernest Tucker has Shown that Nadir Shah's chroniclers depicted him as the restorer of the Safavid dynasty, and appealed to notions of Safavid legitimacy in their histories. One chronicler, Muhammad Kazim Marvi, accomplished this partly by relating how Nadir Shah found a tablet (lawḥ) upon which Timur had inscribed instructions for Nadir Shah. Although Marvi was predominantly appealing to Safavid legitimacy, in the process he also linked Nadir's name with Timur. Laurence Lockhart notes a number of similarities between Nadir and Timur, indicating instances where Nadir seems to have modeled his reign on Timur's. These include (1) Nadir's naming his grandson Shahrukh, (2) Nadir's wife and Timur's daughter-in-law (wife of Shahrukh) both sharing the same name, Gawhar Shad, and (3) Nadir's use of certain Timurid military tactics.
Architecture
Authors: Grabar Oleg
Published: September 2011

It is Very Difficult, in Fact Impossible, to Review Properly What is in fact an incomplete work, one in which many years separate the writing and publication of the first entries from the last ones and in which so much remains to be done. My purpose, in the remarks which follow, is to identify the main policy decisions that seem to have been made in presenting the architecture of the Iranian world, to comment at some length about the success or failure of entries dealing with various categories of presentation, and, all along, to make suggestions about ways of improving access to the information that has been provided. In most cases I did not identify the names of authors, because all of them made choices as to how to interpret their assignments, and the discussion of such choices is not useful in a review at this stage. Competence in the knowledge of their field is clear for all writers, and there are only a few cases of scholars who had not kept up with information or interpretation and whose articles are lacking in substance.
A genomic model of condition-specific nucleosome behavior explains transcriptional activity in yeast
Authors: Zaugg Judith B. , Luscombe Nicholas M.
Published: September 2011

Nucleosomes play an important role in gene regulation. Molecular studies observed that nucleosome binding in promoters tends to be repressive. In contrast, genomic studies have delivered conflicting results: An analysis of yeast grown on diverse carbon sources reported that nucleosome occupancies remain largely unchanged between conditions, whereas a study of the heat-shock response suggested that nucleosomes get evicted at promoters of genes with increased expression. Consequently, there are few general principles that capture the relationship between chromatin organization and transcriptional regulation. Here, we present a qualitative model for nucleosome positioning in Saccharomyces cerevisiae that helps explain important properties of gene expression. By integrating publicly available data sets, we observe that promoter-bound nucleosomes assume one of four discrete configurations that determine the active and silent transcriptional states of a gene, but not its expression level. In TATA-box-containing promoters, nucleosome architecture indicates the amount of transcriptional noise. We show that >20% of genes switch promoter states upon changes in cellular conditions. The data suggest that DNA-binding transcription factors together with chromatin-remodeling enzymes are primarily responsible for the nucleosome architecture. Our model for promoter nucleosome architecture reconciles genome-scale findings with molecular studies; in doing so, we establish principles for nucleosome positioning and gene expression that apply not only to individual genes, but across the entire genome. The study provides a stepping stone for future models of transcriptional regulation that encompass the intricate interplay between cis- and trans-acting factors, chromatin, and the core transcriptional machinery.
Single intravenous and oral dose pharmacokinetics of florfenicol in the channel catfish (Ictalurus punctatus)
Authors: GAUNT P. S. , LANGSTON C. , WRZESINSKI C. , GAO D. , ADAMS P. , CROUCH L. , SWEENEY D. , ENDRIS R.
Published: September 2011

Gaunt, P. S., Langston, C., Wrzesinski, C., Gao, D., Adams, P., Crouch, L., Sweeney, D., Endris, R. Single intravenous and oral dose pharmacokinetics of florfenicol in the channel catfish (Ictalurus punctatus). J. vet. Pharmacol. Therap. 35, 503–507.

Plasma distribution and elimination of florfenicol in channel catfish were investigated after a single dose (10 mg/kg) of intravenous (i.v.) or oral administration in freshwater at a mean water temperature of 25.4 °C. Florfenicol concentrations in plasma were analyzed by means of liquid chromatography with MS/MS detection. After i.v. florfenicol injection, the terminal half‐life (t1/2), volume of distribution at steady state (Vss), and central volume of distribution (Vc) were 8.25 h, 0.9 and 0.381 L/kg, respectively. After oral administration of florfenicol, the terminal t1/2, Cmax, Tmax, and oral bioavailability (F) were 9.11 h, 7.6 μg/mL, 9.2 h, and 1.09, respectively. There was a lag absorption time of 1.67 h in oral dosing. Results from these studies support that 10 mg florfenicol/kg body weight in channel catfish is an efficacious dosage following oral administration.
Serum micronutrient concentrations and childhood asthma: the PIAMA birth cohort study
Authors: van Oeffelen A. A. M. , Bekkers M. B. M. , Smit H. A. , Kerkhof M. , Koppelman G. H. , Haveman‐Nies A. , van der A D. L. , Jansen E. H. J. M. , Wijga A. H.
Published: September 2011

To cite this article: van Oeffelen AAM, Bekkers MBM, Smit HA, Kerkhof M, Koppelman GH, Haveman‐Nies A, van der A DL, Jansen EHJM, Wijga AH. Serum micronutrient concentrations and childhood asthma: the PIAMA birth cohort study. Pediatr Allergy Immunol 2011: 22: 784–793.

Background:  Research suggests an influence of micronutrients on childhood asthma. So far, evidence mainly originates from cross‐sectional studies using nutrient intake data, which is not an accurate measure of nutrient status. This study aimed to investigate the cross‐sectional and prospective associations between serum concentrations of magnesium, vitamin D, selenium, and zinc and prevalence of (severe) asthma, atopy, and bronchial hyperresponsiveness (BHR) in childhood.

Methods:  In the Prevention and Incidence of Asthma and Mite Allergy birth cohort study, serum nutrient concentrations were available for a 4‐yr‐old subgroup (n = 372) and for a different 8‐yr‐old subgroup (n = 328). Yearly questionnaires inquired about asthma prevalence until 8 yr of age. Allergic sensitization was measured at 4 and 8 yr of age; BHR was measured at 8 yr of age. Data were analyzed with logistic regression and generalized estimating equations models.

Results:  There was a consistent (non‐significant) inverse association between serum magnesium concentrations and asthma prevalence. Serum vitamin D concentrations measured at age 4 were inversely associated with asthma at ages 4–8 [e.g., cross‐sectional association between vitamin D tertile 3 vs. 1 and severe asthma: odds ratio (OR): 0.49, 95% confidence interval (CI): 0.25–0.95], whereas vitamin D measured at age 8 was positively associated with asthma at age 8 (e.g., cross‐sectional association between vitamin D tertile 3 vs. 1 and severe asthma: OR: 2.14, 95% CI: 0.67–6.82).

Conclusions:  Our study contributes to the evidence that children with higher serum magnesium concentrations are less likely to have asthma. The associations between serum vitamin D concentrations and asthma were age‐dependent.
New drugs for prostate cancer
Authors: Alifrangis Constantine , O'Hanlon‐Brown Ciara , Tuthill Mark , Waxman Jonathan
Published: September 2011

What's known on the subject? and What does the study add?

Recent studies have demonstrated the efficacy of various new treatments. These have been in diverse areas of therapeutics research, including immunology and targeted biological therapy, as well as in new ways of approaching hormone refractory disease. The present paper seeks to review all of the key advances that have been reported in late‐stage clinical studies and place them into the context of managing patients with advanced prostate cancer.

OBJECTIVE

To describe some of the most exciting late stage clinical developments in the field of new therapies for advanced prostate cancer.

METHODS

Pubmed was searched for articles pertaining to prostate cancer therapeutics clinical trials in the last 3 years.

RESULTS

Key positive trials in the areas of androgen resistance, tumour immunology, molecularly targeted agents and cytotoxics were reviewed and discussed in the context of metastatic prostate cancer.

CONCLUSION

Treatments emerging from these areas of scientific endeavour are progressing into clinical trials and are both good cause for hope in patients, and excellent examples of mechanism based drug discovery.
Survival after partial and radical nephrectomy for the treatment of stage T1bN0M0 renal cell carcinoma (RCC) in the USA: a propensity scoring approach
Authors: Badalato Gina M. , Kates Max , Wisnivesky Juan P. , Choudhury Arindam Roy , McKiernan James M.
Published: September 2011

Study Type – Therapy (cohort)

Level of Evidence 2b

What's known on the subject? and What does the study add?

Partial nephrectomy has become the standard of care for T1a renal tumours, and the application of nephron‐sparing techniques has increasingly been expanded to patients with localized T1b cancers. However, the relative efficacy of partial versus radical nephrectomy for these medium‐sized tumours has yet to be definitively established.

This study employs a propensity scoring approach within a large US population‐based cohort to determine that no survival differences exist among patients with T1b renal tumours undergoing partial versus radical nephrectomy.

OBJECTIVES

To compare survival after partial nephrectomy (PN) vs radical nephrectomy (RN) among patients with stage TIb renal cell carcinoma (RCC) using a propensity scoring approach.

Propensity score analysis is a statistical methodology that controls for non‐random assignment of patients in observational studies.

PATIENTS AND METHODS

Using the Surveillance, Epidemiology, and End Results registry, 11 256 cases of RCCs of 4–7 cm that underwent PN or RN between 1998 and 2007 were identified.

Propensity score analysis was used to adjust for potential differences in baseline characteristics between patients in the two treatment groups.

Overall survival (OS) and cancer‐specific survival (CSS) of patients undergoing PN vs RN was compared in stratified and adjusted analysis, controlling for propensity scores.

RESULTS

In all, 1047 (9.3%) patients underwent PN. For the entire cohort, no difference in survival was found in patients treated with PN as compared with RN, as shown by the adjusted hazard ratio (HR) for OS (1.10; 95% confidence interval [CI]: 0.91–1.36) and renal‐CSS (HR 0.91; 95% CI: 0.65–1.27).

When the cohort was stratified by tumour size and age, no difference in survival was identified between the groups.

CONCLUSIONS

Even when stratified by tumour size and age, a survival difference between PN and RN in a propensity‐adjusted cohort of patients with T1b RCC could not be confirmed.

If validated in prospective studies, PN may become the preferred treatment for T1b renal tumours in centres experienced with nephron‐sparing surgery.
Selective Removal of the Violet Color Produced by Anthocyanins in Procyanidin‐Rich Unfermented Cocoa Extracts
Authors: Wallace Taylor C. , Giusti M. Monica
Published: September 2011

Abstract:  Cacao (Theobroma cacao L.) is rich in procyanidins, a large portion of which degrades during the natural fermentation process of producing cocoa powder. Recent advances in technology have enabled scientists to produce unfermented cocoa powder, preserving the original profile of procyanidins present in cocoa and allowing for the development of highly concentrated procyanidin‐rich extracts. During this process, the anthocyanins naturally present in unfermented cocoa remain intact, producing a violet color in the final extract. The objective of this study was to selectively remove the violet color in procyanidin‐rich extracts produced from unfermented cocoa powder, while maintaining the stability and composition of procyanidins present in the matrix. Several processing parameters, including pH fluctuations, enzymatic treatments, and the addition of potassium meta‐bisulfite, were explored to influence the color of procyanidin‐rich extracts throughout a 60‐d shelf life study. The addition of potassium meta‐bisulfite (500 ppm) was found to be the most effective means of removing the violet color present in the treated extracts (L*= 71.39, a*= 8.44, b*= 9.61, chroma = 12.79, and hue = 48.8˚) as compared to the control (L*= 52.84, a*= 11.08, b*= 2.24, chroma = 11.28, and hue = 11.4˚). The use of potassium meta‐bisulfite at all treatment levels (200, 500, and 1000 ppm) did not show any significant detrimental effects on the stability, composition, or amount of procyanidins present in the extracts over the shelf life period as monitored by UV‐Vis spectrophotometry and HPLC‐MS. This research will enable the food industry to incorporate highly concentrated procyanidin‐rich extracts in food products without influencing the color of the final product.
Thermophysical Characterization of Tilapia Myosin and Its Subfragments
Authors: Reed Zachary H. , Park Jae W.
Published: September 2011

Abstract:  Purified tilapia myosin was digested with α‐chymotrypsin and purified to obtain heavy meromyosin (HMM) and light meromyosin (LMM). The thermophysical properties of Tilapia myosin, HMM, and LMM were characterized. Constantly heated myosin, HMM, and LMM samples showed that aggregates began to form around 40 °C as evidenced by the increase of turbidity for all 3 samples (0.25 mg/mL). Beginning turbidity measurements showed differing levels of absorbance for each protein fragment with increasing absorbance values in the following order HMM, myosin, and LMM (0.0026, 0.0282, and 0.052, respectively). Differential scanning calorimetry showed 3 (17.5, 41.9, and 49.9 °C), 2 (43 and 67.1 °C), and 3 (40.4, 51.7, and 69 °C) major peaks for myosin, HMM, and LMM, respectively. Dynamic rheology measurements demonstrated crossover points, which are generally recognized as gelation point, 40.3 °C for myosin and 27 °C for HMM. The results shown for the thermally stable properties of tilapia myosin, HMM, and LMM showed clear evidence that they are all thermal stable at temperatures ranging from 10 °C to approximately 40 °C after which they all are completely denatured. The results also showed that the thermo stability of the myosin and its subfragments were greatly influenced by fish habitat temperature.
Unpacking Team Familiarity: The Effects of Geographic Location and Hierarchical Role
Authors: Staats Bradley R.
Published: September 2011

Examination of team productivity finds that team familiarity, i.e., individuals' prior shared work experience, can positively impact the efficiency and quality of team output. Despite the attention given to team familiarity and its contingencies, prior work has focused on whether team members have worked together, not on which team members have worked together, and under what conditions. In this paper, I parse overall team familiarity to consider effects of geographic location and the hierarchical roles of team members. Using data on all software‐development projects completed over 3 years at a large Indian firm in the global outsourced software services industry, I find that team familiarity gained when team members work together in the same location has a significantly more positive effect on team performance compared with team familiarity gained while members were collaborating in different locations. Additionally, I find that hierarchical team familiarity (a manager's experience with front‐line team members) and horizontal team familiarity (front‐line team members' experience gained with one another) have differential effects on project team performance. These findings provide insight into the relationship between team experience and team performance.
A New Design Strategy for Minimizing Sound Radiation of Vibrating Beam Using Dimples
Authors: Cheng W. N. , Cheng C. C. , Koopmann G. H.
Published: September 2011

A method is proposed for minimizing the sound radiation of a vibrating beam by patterning the beam with a series of cylindrical dimples such that one or more of the vibration modes have the same shape as the corresponding weak modes. In implementing the proposed approach, the objective is to minimize the shape difference between the vibration mode(s) and the designated weak mode(s) rather than to minimize the radiated sound power at a specific frequency or over a certain bandwidth. The design objective is achieved by calculating the weak modes of the beam using the finite element method and then applying an optimization scheme with the modal assurance criterion (MAC) as the objective function. The optimization results, which cause the vibration mode(s) of the dimpled beam to approach the corresponding weak modes(s), determine the dimple angle and dimple depth. The numerical results show that the radiation efficiency of the optimized dimpled beam using MAC as the objective is generally lower than that of a uniform beam. However, the effectiveness of the proposed design strategy depends on the degree of closeness between the shape of the vibration mode(s) of the dimpled beam and that of the designated weak mode(s).
A Study on Amount of Biomass Pellets Used in Durability Testing
Authors: Zhang Q. , Zhang P. F. , Song X. X. , Zhang M. , Pei Z. J. , Deines T.
Published: September 2011

Biofuels are an alternative to petroleum-based liquid transportation fuels. Cellulosic biomass can be used as feedstocks for befoul manufacturing. Low density of cellulosic feedstocks causes difficulties in handling them during transportation and storage, thus hindering large-scale and cost-effective manufacturing of cellulosic biofuels. Pelleting can increase the density of cellulosic feedstocks by compacting bulky biomass into pellets. Pellet durability, an important quality parameter, measures the ability of pellets to withstand impact and other destructive forces during transportation and handling. ASABE standard S269.4 specifies a procedure to determine pellet durability using 500 grams of pellets. However, it does not provide any justification of choosing this amount of pellets. This paper investigates the feasibility of using a smaller amount of pellets (50 grams) to determine pellet durability. Results show that 50 grams of pellets can generate comparable durability results as 500 grams of pellets.
Holistic Approach for a Simulation-Based Twist Drill Geometry Optimization
Authors: Abele E. , Fujara M. , Scha¨fer D.
Published: September 2011

The optimization of solid carbide twist drills is a very difficult task because of the large number of conflicting design parameters. Former approaches only consider limited design aspects. This article introduces a new holistic simulation-based method for multi-objective twist drill geometry optimization. By using a complete geometry model, numerical simulation models calculate all major properties of the drill. In detail structural stiffness and strength, torque and thrust force, coolant flow resistance, chip evacuation capability and chip flute manufacturability are calculated. Several multi-objective algorithms and evaluation methods are implemented. Hence an entire geometry optimization considering manufacturability and performance is possible.
Finite Element Modeling of Orthogonal Cutting of Pyrolytic Carbon
Authors: Salhotra Gautam , Bajpai Vivek , Singh Ramesh K.
Published: September 2011

Engineered features on pyrolytic carbon (PyC) have been demonstrated as an approach to improve the flow hemodynamics of the cardiovascular implants. In addition, it also finds application in thermonuclear components. These micro/meso scale engineered features are required to be machined onto the PyC leaflet. However, being a layered anisotropic material and brittle in nature, its machining characteristics differ from plastically deformable isotropic materials. Consequently, this study is aimed at creating a finite element model to understand the mechanics of material removal in the plane of transverse isotropy (horizontally stacked laminae) of PyC. A layered model approach has been used to capture the interlaminar shearing and brittle fracture during machining. A cohesive element layer has been used between the chip layer and the machined surface layer. The chip layer and workpiece are connected through a cohesive layer. The model predicts cutting forces and the chip length for different cutting conditions. The orthogonal cutting model has been validated against experimental data for different cutting conditions for cutting and thrust forces. Parametric studies have also been performed to understand effect of machining parameters on machining responses. This model also predicts chip lengths which have also been compared with the actual chip morphology obtained from microgrooving experiments. The prediction errors for cutting force and chip length are within 20% and 33%, respectively.