bluuebunny/crossref_metadata_2025 huggingface dataset:
Some implications of sampling choices on comparisons between satellite and model aerosol optical depth fields
Authors: Sayer A. M. , Thomas G. E. , Palmer P. I. , Grainger R. G.
Published: November 2010

Abstract. The comparison of satellite and model aerosol optical depth (AOD) fields provides useful information on the strengths and weaknesses of both. However, the sampling of satellite and models is very different and some subjective decisions about data selection and aggregation must be made in order to perform such comparisons. This work examines some implications of these decisions, using GlobAerosol AOD retrievals at 550 nm from Advanced Along-Track Scanning Radiometer (AATSR) measurements, and aerosol fields from the GEOS-Chem chemistry transport model. It is recommended to sample the model only where the satellite flies over on a particular day; neglecting this can cause regional differences in model AOD of up to 0.1 on monthly and annual timescales. The comparison is observed to depend strongly upon thresholds for sparsity of satellite retrievals in the model grid cells. Requiring at least 25% coverage of the model grid cell by satellite data decreases the observed difference between the two by approximately half over land. The impact over ocean is smaller. In both model and satellite datasets, there is an anticorrelation between the proportion p of a model grid cell covered by satellite retrievals and the AOD. This is attributed to small p typically occuring due to high cloud cover and lower AODs being found in large clear-sky regions. Daily median AATSR AODs were found to be closer to GEOS-Chem AODs than daily means (with the root mean squared difference being approximately 0.05 smaller). This is due to the decreased sensitivity of medians to outliers such as cloud-contaminated retrievals, or aerosol point sources not included in the model.
Aerosol nucleation and its role for clouds and Earth's radiative forcing in the aerosol-climate model ECHAM5-HAM
Authors: Kazil J. , Stier P. , Zhang K. , Quaas J. , Kinne S. , O'Donnell D. , Rast S. , Esch M. , Ferrachat S. , Lohmann U. , Feichter J.
Published: November 2010

Abstract. Nucleation from the gas phase is an important source of aerosol particles in the Earth's atmosphere, contributing to the number of cloud condensation nuclei, which form cloud droplets. We have implemented in the aerosol-climate model ECHAM5-HAM a new scheme for neutral and charged nucleation of sulfuric acid and water based on laboratory data, and nucleation of an organic compound and sulfuric acid using a parametrization of cluster activation based on field measurements. We give details of the implementation, compare results with observations, and investigate the role of the individual aerosol nucleation mechanisms for clouds and the Earth's radiative forcing. The results of our simulations are most consistent with observations when neutral and charged nucleation of sulfuric acid proceed throughout the troposphere and nucleation due to cluster activation is limited to the forested boundary layer. The globally averaged annual mean contributions of the individual nucleation processes to total absorbed solar short-wave radiation via the direct, semi-direct, indirect cloud-albedo and cloud-lifetime effects in our simulations are −1.15 W/m2 for charged H2SO4/H2O nucleation, −0.235 W/m2 for cluster activation, and −0.05 W/m2 for neutral H2SO4/H2O nucleation. The overall effect of nucleation is −2.55 W/m2, which exceeds the sum of the individual terms due to feedbacks and interactions in the model. Aerosol nucleation contributes over the oceans with −2.18 W/m2 to total absorbed solar short-wave radiation, compared to −0.37 W/m2 over land. We explain the higher effect of aerosol nucleation on Earth's radiative forcing over the oceans with the larger area covered by ocean clouds, due to the larger contrast in albedo between clouds and the ocean surface compared to continents, and the larger susceptibility of pristine clouds owing to the saturation of effects. The large effect of charged nucleation in our simulations is not in contradiction with small effects seen in local measurements: over southern Finland, where cluster activation proceeds efficiently, we find that charged nucleation of sulfuric acid and water contributes on average less than 10% to ultrafine aerosol concentrations, in good agreement with observations.
An accuracy assessment of the CALIOP/CALIPSO version 2 aerosol extinction product based on a detailed multi-sensor, multi-platform case study
Authors: Kacenelenbogen M. , Vaughan M. A. , Redemann J. , Hoff R. M. , Rogers R. R. , Ferrare R. A. , Russell P. B. , Hostetler C. A. , Hair J. W. , Holben B. N.
Published: November 2010

Abstract. The Cloud Aerosol LIdar with Orthogonal Polarization (CALIOP), on board the CALIPSO platform, has measured profiles of total attenuated backscatter coefficient (level 1 products) since June 2006. CALIOP's level 2 products, such as the aerosol backscatter and extinction coefficient profiles, are retrieved using a complex succession of automated algorithms. The goal of this study is to help identify potential shortcomings in the CALIOP version 2 level 2 aerosol extinction product and to illustrate some of the motivation for the changes that will be introduced in the next version of CALIOP data (version 3, currently being processed). As a first step, we compared CALIOP version 2-derived AOD with the collocated MODerate Imaging Spectroradiometer (MODIS) AOD retrievals over the Continental United States. The best statistical agreement between those two quantities was found over the Eastern part of the United States with, nonetheless, a weak correlation (R ~0.4) and an apparent CALIOP version 2 underestimation (by ~66%) of MODIS AOD. To help quantify the potential factors contributing to the uncertainty of the CALIOP aerosol extinction retrieval, we then focused on a one-day, multi-instrument, multiplatform comparison study during the CALIPSO and Twilight Zone (CATZ) validation campaign on August 04, 2007. This case study illustrates the following potential reasons for a bias in the CALIOP AOD: (i) CALIOP's low signal-to-noise ratio (SNR) leading to the misclassification and/or lack of aerosol layer identification, especially close to the Earth's surface; (ii) the cloud contamination of CALIOP version 2 aerosol backscatter and extinction profiles; (iii) potentially erroneous assumptions of the backscatter-to-extinction ratio (Sa) used in CALIOP's extinction retrievals; and (iv) calibration coefficient biases in the CALIOP daytime attenuated backscatter coefficient profiles.
Simple kinematic models for the environmental interaction of tropical cyclones in vertical wind shear
Authors: Riemer M. , Montgomery M. T.
Published: November 2010

Abstract. A major contribution to intensity changes of tropical cyclones (TCs) is believed to be associated with interaction with dry environmental air. However, the conditions under which pronounced TC-environment interaction takes place are not well understood. As a step towards improving our understanding of this problem we analyze the flow topology of a TC in vertical wind shear in an idealized, three-dimensional, convection-permitting numerical experiment. A set of distinct streamlines, the so-called separatrices, can be identified under the assumptions of steady and layer-wise horizontal flow. The separatrices are shown to divide the flow around the TC into distinct regions. The separatrix structure in our numerical experiment is more complex than the well-known flow topology of a non-divergent point vortex in uniform background flow. In particular, one separatrix spirals inwards and ends in a limit cycle, a meso-scale dividing streamline encompassing the eyewall above the inflow and below the outflow layer. Air with the highest values of moist entropy resides within this limit cycle supporting the notion that the eyewall is well protected from intrusion of dry environmental air despite the adverse impact of the vertical wind shear. This "moist envelope" is distorted considerably by the vertical wind shear, and the shape of the moist envelope is closely related to the shape of the limit cycle. A simple kinematic model based on a weakly divergent point vortex in background flow is presented. The model is shown to capture the essence of many salient features of the flow topology in the idealized experiment. A regime diagram representing realistic values of TC intensity and vertical wind shear can be constructed for this simple model. The results indicate distinct scenarios of environmental interaction depending on the ratio of storm intensity and shear magnitude. Further implications of the new results derived from the flow topology analysis for TCs in the real atmosphere are discussed.
Dependence of the single-scattering properties of small ice crystals on idealized shape models
Authors: Um J. , McFarquhar G. M.
Published: November 2010

Abstract. Small ice crystals (with maximum dimension <50 μm) appear quasi-circular when imaged by probes on aircraft flying through cloud. Therefore, idealized models constructed to calculate their single-scattering properties have included quasi-spherical models such as Chebyshev particles, Gaussian random spheres, and droxtals. Recently, an ice analogue grown from sodium fluorosilicate solution on a glass substrate, with several columns emanating from a common center of mass, was shown to be quasi-circular when imaged by state-of-the-art cloud probes. In this study, a new idealized model, called the budding Bucky ball (3B) that resembles the shape of the small ice analogue is developed. The corresponding single-scattering properties (scattering phase function P11 and asymmetry parameter g) are computed by a ray-tracing code. Compared with previosly used models, 3B scatters less light in the forward and more light in the lateral and backward directions. The Chebyshev particles and Gaussian random spheres show smooth and featureless P11, whereas droxtals and 3Bs, which have a faceted structure, show several peaks in P11 associated with angles of minimum deviation. Overall, the difference in the forward (lateral; backward) scattering between models are up to 22% (994%; 132%), 20% (510%; 101%), and 16% (146%; 156%) for small ice crystals with repective area ratios of 0.85, 0.77, and 0.69. The g for different models varies by up to 25%, 23%, and 19% for particles with area ratios of 0.85, 0.77, and 0.69, respectively. Becuase the single-scattering properties of small ice crystals depend both on the choice of the idealized model and the area ratios used to characterize the small ice crystals, higher resolution observations of small ice crystals or direct observations of their single-scattering properties are required.
Dynamic Solution Injection: a new method for preparing pptv–ppbv standard atmospheres of volatile organic compounds
Authors: Jardine K. J. , Henderson W. M. , Huxman T. E. , Abrell L.
Published: November 2010

Abstract. Proton Transfer Reaction-Mass Spectrometry (PTR-MS) and thermal desorption Gas Chromatography-Mass Spectrometry (GC-MS) allow for absolute quantification of a wide range of atmospheric volatile organic compounds (VOCs) with concentrations in the ppbv to pptv range. Although often neglected, routine calibration is necessary for accurate quantification of VOCs by PTR-MS and GC-MS. Several gas calibration methods currently exist, including compressed gas cylinders, permeation tubes, diffusion tubes, and liquid injection. While each method has its advantages and limitations, no single technique has emerged that is capable of dynamically generating known concentrations of complex mixtures of VOCs over a large concentration range (ppbv to pptv) and is technically simple, field portable, and affordable. We present the development of a new VOC calibration technique based on liquid injection with these features termed Dynamic Solution Injection (DSI). This method consists of injecting VOCs (0.1–0.5 mM) dissolved in cyclohexane (PTR-MS) or methanol (GC-MS) into a 1.0 slpm flow of purified dilution gas in an unheated 25 ml glass vial. Upon changes in the injection flow rate (0.5–4.0 μl min−1), new VOC concentrations are reached within seconds to minutes, depending on the compound, with a liquid injection flow rate accuracy and precision of better than 7% and 4% respectively. We demonstrate the utility of the DSI technique by calibrating a PTR-MS to seven different cyclohexane solutions containing a total of 34 different biogenic compounds including volatile isoprenoids, oxygenated VOCs, fatty acid oxidation products, aromatics, and dimethyl sulfide. We conclude that because of its small size, low cost, and simplicity, the Dynamic Solution Injection method will be of great use to both laboratory and field VOC studies.
Understanding and managing the Westerschelde – synchronizing the physical system and the management system of a complex estuary
Authors: van Buuren A. , Gerrits L. , Teisman G. R.
Published: November 2010

Abstract. This article analyzes the relationship between the processes of policy making, management and research and the way in which the Westerschelde estuary developed between 1985 and 2006. The Westerschelde has three core functions: economically: it makes the port of Antwerp accessible; ecologically: it generates habitats for certain unique species; and in terms of safety: its morphology helps preventing the hinterland from being flooded. We analyze how the processes of policymaking, management and analysis focused on these three aspects, and how they in turn affected the physical system of the Westerschelde. We proceed to develop a framework for evaluating the policy making, management and esearch and how this impacts the Westerschelde. We apply this framework to twenty years of policy making on, management of, and research about the Westerschelde. We conclude that policy, management and research, due to learning effects, take the dynamics of the Westerschelde into account to a greater extent than they have in the past, but there exist a real probability for old routines to return.
Modern comprehensive approach to monitor the morphodynamic evolution of restored river corridors
Authors: Pasquale N. , Perona P. , Schneider P. , Shrestha J. , Wombacher A. , Burlando P.
Published: November 2010

Abstract. River restoration has become a common measure to repair anthropogenically-induced alteration of fluvial ecosystems. The inherent complexity of ecohydrologic systems, leads to limitations in understanding the response of such systems to restoration over time. Up to now a lot of effort has therefore been dedicated worldwide to document the efficiency of restoration actions and to produce new effective guidelines that may help overcoming our deficiencies. At the same time very few attentions focused on illustrating the reasons and the use of certain monitoring and experimental techniques in spite of others, or in relation to the specific ecohydrologic process being investigated. The purpose of this paper is to enrich efforts in this direction by discussing the experimental setup that we designed and installed in order to accomplish some of the research tasks of the multidisciplinary scientific project RECORD (Restored Corridor Dynamics). Therein, we study the morphodynamic evolution of the restored reaches of River Thur near Niederneunforn (Switzerland), also in relation to the role of pioneer vegetation roots in stabilizing the alluvial sediment. In this work we describe and motivate the methodology chosen for monitoring the river morphodynamics, the dynamics of riparian and of in-bed vegetation and their mutual interactions, as well as the need of complementing such observations with experiments and with the hydraulic modeling of the site. We also discuss how the designed installation and the experiments integrate with the needs of other research groups within the project, in particular providing data for a number of investigations ranging from surface water to groundwater, soil moisture and vegetation dynamics.
Bias correction of satellite rainfall estimation using a radar-gauge product
Authors: Tesfagiorgis K. , Mahani S. E. , Khanbilvardi R.
Published: November 2010

Abstract. Satellite rainfall estimates can be used in operational hydrologic prediction, but are prone to systematic errors. The goal of this study is to seamlessly blend a radar-gauge product with a corrected satellite product that fills gaps in radar coverage. To blend different rainfall products, they should have similar bias features. The paper presents a pixel by pixel method, which aims to correct biases in hourly satellite rainfall products using a radar-gauge rainfall product. Bias factors are calculated for corresponding rainy pixels, and a desired number of them are randomly selected for the analysis. Bias fields are generated using the selected bias factors. The method takes into account spatial variation and random errors in biases. Bias field parameters were determined on a daily basis using the Shuffled Complex Evolution optimization algorithm. To include more sources of errors, ensembles of bias factors were generated and applied before bias field generation. The procedure of the method was demonstrated using a satellite and a radar-gauge rainfall data for several rainy events in 2006 for the Oklahoma region. The method was compared with bias corrections using interpolation without ensembles, the ratio of mean and maximum ratio. Results show the method outperformed the other techniques such as mean ratio, maximum ratio and bias field generation by interpolation.
Upper ocean stratification and sea ice growth rates during the summer-fall transition, as revealed by Elephant seal foraging in the Adélie Depression, East Antarctica
Authors: Williams G. D. , Hindell M. , Houssais M.-N. , Tamura T. , Field I. C.
Published: November 2010

Abstract. Southern elephant seals (Mirounga leonina), fitted with Conductivity-Temperature-Depth sensors at Macquarie Island in January 2005 and 2010, collected unique oceanographic observations of the Adélie and George V Land continental shelf (140–148° E) during the summer-fall transition (late February through April). This is a key region of dense shelf water formation from enhanced sea ice growth/brine-rejection in the local coastal polynyas. In 2005 two seals occupied the continental shelf break near the grounded icebergs at the northern end of the Mertz Glacier Tongue for nearly two weeks at the onset of sea ice growth. One of the seals migrated north thereafter and the other headed west, possibly utilising the Antarctic Slope Front current near the continental shelf break. In 2010, after that years calving of the Mertz Glacier Tongue, two seals migrated to the same region but penetrated much further southwest across the Adélie Depression and occupied the Commonwealth Bay polynya from March through April. Here we present unique observations of the regional oceanography during the summer-fall transition, in particular (a) the zonal distribution of modified Circumpolar Deep Water exchange across the shelf break, (b) the upper ocean stratification across the Adélie Depression, including alongside iceberg C–28 that calved from the Mertz Glacier and (c) the convective overturning of the deep remnant seasonal mixed layer in Commonwealth Bay from sea ice growth (7.5–12.5 cm s−1). Heat and freshwater budgets to 200–300 m are used to estimate the ocean heat content, heat flux and sea ice growth rates. We speculate that the continuous foraging by the seals within Commonwealth Bay during the summer-fall transition was due to favorable feeding conditions resulting from the convective overturning of the deep seasonal mixed layer and chlorophyll maximum that is a reported feature of this location.
On the Use of Laguerre Tessellations for Representations of 3D Grain Structures
Authors: Lyckegaard Allan , Lauridsen Erik Mejdal , Ludwig Wolfgang , Fonda Richard Warren , Poulsen Henning Friis
Published: November 2010

Accurate descriptions of 3D grain structures in polycrystalline materials are of key interest as the grain structure is closely correlated to the macroscopic properties of the material. In the present study, we investigate the accuracy of using Laguerre tessellations to represent 3D grain structures from only the spatial center of mass location and the volume of the grains. The ability of Laguerre tessellations to describe accurate grain shapes and topologies of real 3D grain structures are revealed by direct comparison to 3D reconstructions of an un‐deformed meta‐stable β ‐titanium alloy obtained by phase‐contrast micro‐tomography. This study reveals that (volume weighted) Laguerre tessellations are superior to classical Voronoi tessellations when it comes to providing accurate representations of real 3D grain structures. Furthermore, although the Laguerre tessellations were only able to correctly describe the local arrangements of grains (i.e., the grain neighbors and number of grain facets) for 31.8% of the investigated grains, the Laguerre tessellations were able to accurately describe statistical grain characteristics such as grain size distributions and grain neighbor distributions.
Efficient Synthesis of Novel Bis(dipyrromethanes) with Versatile Linkers via Indium(III) Chloride‐Catalyzed Condensation of Pyrrole and Dialdehydes
Authors: Zhao Hongbin , Liao Junxu , Ning Jingheng , Xie Yujia , Cao Yingjie , Chen Liang , Yang Deliang , Wang Bangying
Published: November 2010

A new efficient and mild protocol for synthesizing a series of novel bis(dipyrromethanes) with versatile arylene linkers through an indi‐ um(III) chloride‐catalyzed condensation reaction between various dialdehydes and pyrrole has been developed. This protocol is applicable to constructing a variety of bis(dipyrromethanes) with diverse functional linkers, which provides a powerful route to construct libraries of functionalized porphyrin dimers and even multiporphyrin arrays.
Enantioselective Organocatalytic Rearrangement of α‐Acyloxy‐ β‐keto Sulfides to α‐Acyloxy Thioesters
Authors: Capitta Francesca , Frongia Angelo , Piras Pier Paolo , Pitzanti Patrizia , Secci Francesco
Published: November 2010

The first highly enantioselective organocatalytic rearrangement of α‐acyloxy‐β‐keto sulfides to α‐acyloxy thioesters has been developed which provides a number of important synthetic building blocks in high yield and with excellent enantioselectivities (ee: up to 92%).
Reusable Chiral Dicationic Chromium(III) Salen Catalysts for Aminolytic Kinetic Resolution of trans‐Epoxides
Authors: Kureshy Rukhsana I. , Prathap K. Jeya , Roy Tamal , Maity Nabin Ch. , Khan Noor‐ul H. , Abdi Sayed H. R. , Bajaj Hari C.
Published: November 2010

A series of new recyclable chiral dicationic chromium(III) salen complexes 1–10 bearing different substituents, viz., hydrogen, methyl, tert‐butyl, triphenylphosphinomethyl, triethylaminomethyl, methylimidazolium, methylpyridinium, methyl‐N,N‐dimethylpyridinium at the 3,3′‐ and 5,5′‐ positions of the salen unit with (1S,2S)‐(+)‐1,2‐diaminocyclohexane, (1S,2S)‐(−)‐1,2‐diphenyl‐1,2‐diaminoethane, and (S)‐(−)‐1,1′‐binaphthyl‐2,2′‐diamine collars have been synthesized and characterized by various physico‐chemical methods. These complexes were used as catalysts for the highly enantioselective aminolytic kinetic resolution of racemic trans‐epoxides with different anilines as nucleophiles at room temperature. With the use of catalyst 3, anti‐β‐amino alcohols were obtained in excellent yields (>99% with respect to the nucleophile) and enantioselectivities (ee>99%) with the concomitant recovery of corresponding epoxides in high optical purity (ee up to >99%) and quantitative yields in 12 h. The catalyst 3 is recyclable in the aminolytic kinetic resolution process and worked well up to six cycles with retention of enantioselectivity.
Carbenes Made Easy: Formation of Unsymmetrically Substituted N‐Heterocyclic Carbene Complexes of Palladium(II), Platinum(II) and Gold(I) from Coordinated Isonitriles and their Catalytic Activity
Authors: Hashmi A. Stephen K. , Lothschütz Christian , Böhling Constantin , Hengst Tobias , Hubbert Christoph , Rominger Frank
Published: November 2010

From palladium(II) or platinum(II) bis(isonitrile) complexes and from gold(I) isonitrile complexes, both easily available from simple precursors, the corresponding mono‐N‐heterocyclic carbene (NHC) complexes could be obtained selectively in good yields under very mild conditions. The reagents are simple β‐chloroammonium salts in the presence of a weak base. Unsymmetric NHC complexes are accessible. Thus over only two steps from simple metal precursors a broad variety of NHC complexes is available, the method is ideal to quickly assemble catalyst libraries. The palladium complexes are active pre‐catalysts in Suzuki cross‐coupling even with the additional isonitrile ligand on palladium.
“On Water” Direct and Site‐Selective Pd‐Catalysed CH Arylation of (NH)‐Indoles
Authors: Joucla Lionel , Batail Nelly , Djakovitch Laurent
Published: November 2010

This communication describes the development of a versatile catalytic system based on palladium(II) acetate/bis(diphenylphosphino)methane [Pd(OAc)2/dppm] that works “on water” giving site‐selective CH arylation of (NH)‐indoles without protecting or directing groups. Remarkably, the control of regioselectivity was achieved by small changes in the “extra‐catalytic” base/halide partners. These innovative methodologies allow a high‐yielding access to both C2 and C3‐arylindoles, as well as 2,3‐diarylindoles, and display high chemo/regioselectivities and structural versatility with regard to either indole or aryl moieties.
Metal Organic Frameworks as Solid Acid Catalysts for Acetalization of Aldehydes with Methanol
Authors: Dhakshinamoorthy Amarajothi , Alvaro Mercedes , Garcia Hermenegildo
Published: November 2010

Room temperature acetalization of aldehydes with methanol has been carried out using metal organic frameworks (MOFs) as solid heterogeneous catalysts. Of the MOFs tested, a copper‐containing MOF [Cu3(BTC)2] (BTC=1,3,5‐benzenetricarboxylate) showed better catalytic activity than an iron‐containing MOF [Fe(BTC)] and an aluminium containing MOF [Al2(BDC)3] (BDC=1,4‐benzenedicarboxylate). The protocol was validated for a series of aromatic and aliphatic aldehydes and used to protect various aldehydes into commercially important acetals in good yields without the need of water removal. In addition, the reusability and heterogeneity of this catalytic system was demonstrated. The structural stability of MOF was further studied by characterization with powder X‐ray diffraction, Brunauer–Emmett–Teller surface area measurements and Fourier‐transformed infrared spectroscopic analysis of a deactivated catalyst used to convert a large amount of benzaldehyde. The performance of copper MOF as acetalization catalyst compares favourably with those of other conventional homogeneous and heterogeneous catalysts such as zinc chloride, zeolite and clay.
Asymmetric Synthesis of cis‐3,4‐Disubstituted Chromans and Dihydrocoumarins via an Organocatalytic Michael Addition/ Hemiacetalization Reaction
Authors: Enders Dieter , Wang Chuan , Yang Xuena , Raabe Gerhard
Published: November 2010

The organocatalytic domino Michael/hemiacetalization reaction between various aldehydes and ortho‐nitrovinylphenols has been developed. Under the catalysis of diphenyl prolinol trimethylsilyl ether, cis‐3,4‐disubstituted chromanols are obtained in high to excellent yields (81–98%) and stereoselectivities (dr: 86:14 to >99:1, ee 96 to >99%). The corresponding disubstituted chromans are available by dehydroxylation of the domino products in good to excellent yields (58–95%). Furthermore, oxidation of the domino products with pyridinium chlorochromate provided 3,4‐dihydrocoumarins in good yields (65–83%) without any epimerization.
Helical flow of polymer melts in extruders, part II: Model simulation and validation
Authors: Sanjabi Farshid , Upreti Simant R. , Lohi Ali , Ein‐Mozaffari Farhad
Published: November 2010

This paper is a sequel to the development of the mathematical model carried out in Part I of this work. The model describes the flow of a polymer melt inside the helical channel of an injection‐molding machine. In this initiative, we develop an iterative computational algorithm based on shooting Newton–Raphson method to simulate the mathematical model. The simulation results are validated against experimental data obtained from 10 different runs of an industrial injection molding machine processing two different polymers–‐ high‐density polyethylene and polyethylene terephthalate. It is observed that the simulation results are in good agreement with experimental data. This outcome demonstrates the utility of the developed mathematical model and simulation approach. From the standpoint of industrial practice, the direct benefit of this work is the ability to effectively calculate adequate shot size, recovery rate, and various state variables throughout the extent of the machine. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:261–279, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.20193
Crystallization and enzymatic hydrolysis of PLA grade for orthopedics
Authors: Papageorgiou George Z. , Beslikas Theodore , Gigis John , Christoforides John , Bikiaris Dimitrios N.
Published: November 2010

Poly(lactic acid) (PLA) absorbable reinforcement ligaments that are used in orthopedics for the repair and reinforcement of articulation instabilities as well as PLA samples synthesized in the laboratory were studied with respect to their thermal properties, crystallization kinetics, mechanical properties, and enzymatic hydrolysis. For these purposes, thermogravimetric analysis, differential scanning calorimetry (DSC), step‐scan modulated temperature DSC, hot stage polarized light microscopy (PLM), scanning electron microscopy, tensile testing, and enzymatic hydrolysis experiments were performed on both cases of samples and findings were compared. The PLA ligament showed higher tensile properties and higher crystallization rates under both isothermal and nonisothermal conditions. Isothermal crystallization and cold crystallization kinetics were studied using various models. The effective energy barrier of nonisothermal crystallization was also evaluated using the isoconversional method of Friedman. The generated morphology in the case of isothermal crystallization was observed with the use of PLM, and the spherulite growth rates were calculated. Finally, both materials showed very slow enzymatic degradation rates, although in the case of the reinforcement ligament they were substantially higher compared to the laboratory PLA sample. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:280–299, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.20194
Parental investment and socioeconomic status influences on children's height in Honduras: An analysis of national data
Authors: Sparks Corey S.
Published: November 2010

Objectives: This research analyzes variation in children's height‐for‐age z‐scores from a nationally representative sample of children from Honduras in 2006. This work draws on theoretical perspectives from parental investment theory to describe the mediating effects that parental investment may have on children's health and nutrition, even in low socioeconomic status households.

Methods: This research uses the 2006 Demographic and Health Survey for the country of Honduras. The dependent variable is the child's height‐for‐age z‐score (HFAZ). Variation in the HFAZ is analyzed using multiple regression and multilevel regression models to incorporate individual, family and higher‐level predictors.

Results: The findings suggest that children who are more invested in by their parents had better outcomes (HFAZ) than children whose parents did not invest as much. Of the three measures of parental investment used in this study, child wantedness and adequate prenatal care represented significant effects on children's HFAZ, and breastfeeding duration exhibited an interactive effect with household socioeconomic status.

Conclusions: Results suggest that families that can invest more in their children through breastfeeding and sufficient prenatal care can mediate the negative effects of poor socioeconomic status on their children's health. This suggests that these measures of investment used here may be effective at mediating the negative effects of low socioeconomic status for this particular child health outcome. Am. J. Hum. Biol., 2011. © 2010 Wiley‐Liss, Inc.
Association between sleep duration and body size differs among three Hispanic groups
Authors: Knutson Kristen L.
Published: November 2010

Objectives: Although numerous studies have reported negative associations between sleep duration and body size, no studies of this association have focused on Hispanic groups, which was the goal of this work.

Methods: Data are from adults in the 1982–1984 Hispanic Health and Nutrition Examination Survey (HHANES), which enrolled Cuban‐Americans, Mexican‐Americans, and Puerto Ricans. HHANES included self‐reported sleep duration and several anthropometric measures. Principle component analysis extracted a single variable to represent body size. Linear regression models stratified by Hispanic group predicted body size from sleep duration adjusting for age, sex, education, income, marital status, household size, and acculturation.

Results: Average age was 36–44 years and 52–64% were women. Average sleep duration was 7.3–7.7 h. Shorter sleep duration was associated with larger body size in Mexican‐Americans only. The regression coefficient indicated that on average a Mexican‐American adult who reported sleeping for 4 h would have a body size that was larger by 0.12 times the standard deviation for body size than a Mexican‐American adult reporting 8 h of sleep (all other covariates being equal). This effect was similar to the effect of 10 years of age, which would be associated with an increase in body size by 0.10 times the standard deviation of body size.

Conclusions: These results underscore the importance of examining factors associated with obesity in different ethnic groups. It may be inappropriate to combine different Hispanic ethnicities together. Am. J. Hum. Biol., 2011. © 2010 Wiley‐Liss, Inc.
Variability in dental caries prevalence between male and female foragers from the Late/Final Jomon period: Implications for dietary behavior and reproductive ecology
Authors: Temple Daniel H.
Published: November 2010

Objectives

This study documents sex differences in dental caries prevalence among Late to Final Jomon period (4000 through 2300 BP) foragers from Japan and interprets the results within behavioral, dietary, and reproductive context.

Methods

The presence/absence of carious lesions was recorded from ∼1600 Late/Final Jomon period teeth. Frequencies and mean numbers of carious teeth were compared between males and females according to age, tooth group, and region using Fisher's exact and t tests.

Results

Significantly greater frequencies of carious molar teeth were observed in females compared to males in each age group. Few differences were observed between older and younger females as well as between females from high and low density regions. Significantly greater prevalence of cariogenic molars were, however, observed between females in Age Group 3 from a high compared to low density region. Significantly greater average numbers of carious molar teeth were found in females compared to males, with no significant differences in mean number of carious teeth between age groups.

Conclusions

Differences in carious teeth between the sexes likely reflect behavioral and dietary variation for males and females. Limited differences in caries prevalence and mean number of carious teeth between female age groups and regions of varying population density suggests that reproductive factors played a minor role in dental caries variation between males and females. Am. J. Hum. Biol., 2011. © 2010 Wiley‐Liss, Inc.
Genetic influences on serum bilirubin in American Indians: The strong heart family study
Authors: Melton Phillip E. , Haack Karin , Göring Harald H. , Laston Sandy , Umans Jason G. , Lee Elisa T. , Fabsitz Richard R. , Devereux Richard B. , Best Lyle G. , Maccluer Jean W. , Almasy Laura , Cole Shelley A.
Published: November 2010

Objective

To identify genetic variation influencing serum bilirubin levels in American Indians, we performed genome‐wide screening and association analyses in the Strong Heart Family Study. Bilirubin is an endogenous antioxidant that has demonstrated an inverse relationship with cardiovascular disease. Genetic variation within the promoter region of uridine diphosphate glucuronosyltransferase (UGT1A1) on chromosome 2q has been associated with elevated serum bilirubin levels in European populations. However, no study has investigated the UGT1A1 promoter in American Indians.

Methods

Statistical analyses were carried out with 3,484 participants aged 14 to 93 years recruited from three geographic areas in the United States; Arizona, Oklahoma, and North and South Dakota.

Results

Variance components linkage analysis detected a quantitative trait locus (QTL) for bilirubin on chromosome 2q in the combined centers (LOD = 6.61, P = 4.24 × 10−6) and in Oklahoma (LOD = 5.65, P = 4.57 24 × 10−5). Genetic association of the UGT1A1 promoter polymorphism was significant for all geographic locations. After adjustment using conditional linkage for UGT1A1 promoter variance, the linkage signal dropped to 1.10 in the combined sample and to 3.32 (P = 0.02) in Oklahoma, indicating this polymorphism is not completely responsible for the linkage signal in American Indians. We also detected suggestive linkage signals in the Dakotas on chromosome 10p12 (LOD = 2.18) and in the combined centers (LOD = 2.24) on chromosome 10q21.

Conclusions

Replication of a serum bilirubin QTL on chromosome 2q in American Indians implicates UGT1A1 but further genotyping is warranted to identify additional causative polymorphisms. Evidence also supports a potential novel locus for bilirubin on chromosome 10. Am. J. Hum. Biol., 2011. © 2010 Wiley‐Liss, Inc.
An updated analysis of pubertal linear growth characteristics and age at menarche in ethnic Chinese
Authors: Mao Sai‐Hu , Li Hai‐Bo , Jiang Jun , Sun Xu , Cheng Jack C.Y. , Qiu Yong
Published: November 2010

Objectives

Concerns regarding change in the onset and tempo of pubertal growth in ethnic Chinese have posed a need for current information on growth characteristics. This study is to update the normative data of pubertal linear growth characteristics and distribution of age at menarche in healthy Chinese adolescents.

Methods

A multistage stratified cluster sampling investigation based on age and sex was designed for anthropometric data collection in 2008, including 15,204 healthy boys and 13,047 healthy girls. The PB1 mathematical growth model was utilized to derive biological parameters of the adolescent growth curves. Ages at menarche were estimated in 6,476 girls through probit analysis at the ages at which 10%, 25%, 50%, 75%, and 90% of the girls attained menarche.

Results

The peak growth age (PGA) was 12.6 years for boys and 10.6 years for girls. The PHV was 6.91 cm/yr in boys and 6.69 cm/yr in girls. The overall increments of adult height since 1985 were 3.3 cm for males and 2.3 cm for females, yielded rates of 1.4 and 1.0 cm/decade, respectively. Less than 10% of Chinese girls experience onset of menses before 11.38 years, and approximately 90% of all Chinese girls are menstruating by 13.88 years, with a median age of 12.63 years.

Conclusions

The current study showed an advancing trend in PGA in both Chinese boys and girls. Decreasing menarche age was also observed for Chinese girls. These updated data would serve as useful reference for interpretation of endocrine and growth status and growth disorders in Chinese during peripubertal period. Am. J. Hum. Biol., 2011. © 2010 Wiley‐Liss, Inc.
IRF6mutations in mixed isolated familial clefting
Authors: Rutledge Katherine D. , Barger Christina , Grant John H. , Robin Nathaniel H.
Published: November 2010

Mutations in the interferon regulatory factor 6 (IRF6) gene are known to cause van der Woude syndrome (VWS), a common syndromic form of oro‐facial clefting characterized by the familial occurrence of mixed clefting (cleft lip with or without a cleft palate and cleft palate alone in the same family) and lower lip pits. As lip pits are not present in all cases of VWS,IRF6mutations can cause a phenotype identical to non‐syndromic clefting. However, recent studies failed to identifyIRF6mutations in sporadic and familial non‐syndromic clefting, concluding that testing forIRF6was not warranted for sporadic or familial non‐syndromic clefting. Here we report on two families that demonstrate familial mixed clefting in which mutations inIRF6were identified, suggesting thatIRF6testing does have a role in familial, non‐syndromic OFC. © 2010 Wiley‐Liss, Inc.
Clinical report of microphthalmia and optic nerve coloboma associated with a de novo microdeletion of chromosome 16p11.2
Authors: Bardakjian Tanya M. , Kwok Simon , Slavotinek Anne M. , Schneider Adele S.
Published: November 2010

Anophthalmia and microphthalmia are etiologically and clinically heterogeneous. We present a 13‐year‐old boy with microphthalmia and multiple anomalies who was evaluated as part of our research into the etiology of microphthalmia. His clinical features included left microphthalmia, persistent hyperplastic primary vitreous and posterior coloboma, right posterior pole coloboma, pectus excavatum, mild hypotonia, mild delays in speech and motor development, and an anxiety disorder with social difficulties. Investigations with a chromosome microarray revealed a de novo deletion of chromosome 16p11.2 of approximately 882 kb in size. Deletions of this region of chromosome 16p11.2 are a newly delineated microdeletion syndrome, but this is the first report of microphthalmia and coloboma associated with monosomy for 16p11.2, and emphasizes the clinical variability that can be present with this deletion. This report contributes to the growing knowledge regarding this microdeletion and suggests that rare copy number changes may be a cause of microphthalmia and other eye anomalies. © 2010 Wiley‐Liss, Inc.
Genetic basis of potential therapeutic strategies for craniosynostosis
Authors: Melville Heather , Wang Yingli , Taub Peter J. , Jabs Ethylin Wang
Published: November 2010

Craniosynostosis, the premature fusion of one or more cranial sutures, is a common malformation of the skull that can result in facial deformity and increased intracranial pressure. Syndromic craniosynostosis is present in ∼15% of craniosynostosis patients and often is clinically diagnosed by neurocranial phenotype as well as various other skeletal abnormalities. The most common genetic mutations identified in syndromic craniosynostosis involve the fibroblast growth factor receptor (FGFR) family with other mutations occurring in genes for transcription factors TWIST, MSX2, and GLI3, and other proteins EFNB1, RAB23, RECQL4, and POR, presumed to be involved either upstream or downstream of the FGFR signaling pathway. Both syndromic and nonsyndromic craniosynostosis patients require early diagnosis and intervention. The premature suture fusion can impose pressure on the growing brain and cause continued abnormal postnatal craniofacial development. Currently, treatment options for craniosynostosis are almost exclusively surgical. Serious complications can occur in infants requiring either open or endoscopic repair and therefore the development of nonsurgical techniques is highly desirable although arguably difficult to design and implement. Genetic studies of aberrant signaling caused by mutations underlying craniosynostosis in in vitro calvarial culture and in vivo animal model systems have provided promising targets in designing genetic and pharmacologic strategies for systemic or adjuvant nonsurgical treatment. Here we will review the current literature and provide insights to future possibilities and limitations of therapeutic applications. © 2010 Wiley‐Liss, Inc.
Comments on a paper by B. Schulz about Bell's inequalities
Authors: Schmelzer I.
Published: November 2010

Schulz claims to have constructed an actively local stochastic theory which violates Bell's inequality. This is false.
Morphology of the Lumbar Transversospinal Muscles Examined in a Mouse Bearing a Muscle Fiber‐Specific Nuclear Marker
Authors: Cornwall Jon , Deries Marianne , Duxson Marilyn
Published: November 2010

Although the morphology of human lumbar transversospinal (TSP) muscles has been studied, little is known about the structure of these muscles in the mouse (Mus musculus). Such information is relevant given mice are often used as a “normal” phenotype for studies modeling human development. This study describes the gross morphology, muscle fiber arrangement, and innervation pattern of the mouse lumbar TSP muscles. A unique feature of the study is the use of a transgenic mouse line bearing a muscle‐specific nuclear marker that allows clear delineation of muscle fiber and connective tissue boundaries. The lumbar TSP muscles of five mice were examined bilaterally; at each spinal level muscles attached to the caudal edge of the spinous process and passed caudally as a single complex unit. Fibers progressively terminated over the four vertebral segments caudad, with multiple points of muscle fiber attachment on each vertebra. Motor endplates, defined with acetylcholinesterase histochemistry, were consistently located half way along each muscle fiber, regardless of length, with all muscle fibers arranged in‐parallel rather than in‐series. These results provide information relevant to interpretation of developmental and functional studies involving this muscle group in the mouse and show mouse lumbar TSP muscles are different in form to descriptions of equivalent muscles in humans and horses. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.
Proximal Testicular Ducts of the Mediterranean Gecko (Hemidactylus turcicus)
Authors: Rheubert Justin L. , Sever David M. , Geheber Aaron D. , Siegel Dustin S.
Published: November 2010

The efferent ducts of the Mediterranean Gecko, Hemidactylus turcicus (Gekkonidae) were investigated using light and electron microscopy. The seminiferous tubules unite into a single rete testis tubule. The rete testis divides into 3–4 ductuli efferentes which all drain into the cranial portion of the ductus epididymis. All efferent ducts are most active during the months of December to August. The rete testis is composed of a simple squamous epithelium with bifurcated nuclei and a labyrinthine network of intercellular canaliculi. Ciliated and nonciliated cells are present, and more than one cilium extends from the scattered ciliated cells. The presence of small clear vesicles and widened intercellular canaliculi suggest that cells of the rete testis are responsible for intake of luminal fluids. The ductuli efferentes are composed of a simple cuboidal epithelium consisting of ciliated and nonciliated cells, and ciliated cells are the dominant cell type. During the inactive season the number of lysosomes increases and the cells become spermiophagic. The ductus epididymis is composed of a tall pseudostratified columnar epithelium with relatively scarce basal cells. No evidence for regionalization was observed. The ductus epididymis is highly secretory during the active season with numerous electron‐dense secretory granules, whose glycoprotein products are released by merocrine secretion. Basally, the active epididymis has swollen intercellular canaliculi and enlarged cisternae of rough endoplasmic reticulum. During the inactive season the secretory activity decreases and membranous structures and fibrous material are observed within widened intercellular canaliculi apical to the basal cells. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.