bluuebunny/crossref_metadata_2025 huggingface dataset:
Lamination for subdermal implant fixation
Authors: Hori Bryan D. , Petrell Royann J. , Trites Andrew W. , Godbey Tamara
Published: April 2009

Thirty‐six aluminum oxide laminated discs were implanted into 12 young rabbits (18 with a 0.5‐mm porous layer and 18 with 1 mm) to determine whether implants that are porous only on one side could fixate to subcutaneous tissue. After 3 months, discs were encased within thin pouches (0.02–0.14 mm) of fibrous connective tissue, as would have been expected of a completely porous implant. Solid sides showed no, while the porous sides showed little, attachment to pouches. Forty‐seven percentage (17) of the discs had moved 1.4 ± 0.8 cm beyond the 4.7 + 1 cm they had moved due to normal skin growth, while two others had moved between 6.2 and 6.5 cm beyond this measure. The proportion of 1 mm porous layer discs migrating within subcutaneous tissue was no greater than the proportion of 0.5 mm layer discs migrating (p = 0.15). Porous layer height and disc migration did not affect the attachment strength of pouch to surrounding tissues (68 ± 23 N, p = 0.34). Pouch thickness, which has been associated to the level of applied forces in other studies, increased with migration distance (p = 0.054). Results indicate that one‐sided porous discs are likely easier to retrieve than completely porous ones, but cannot be prevented from migrating in loose tissue of young animals. Data is being used to design subdermal radio frequency devices for endangered marine animals. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2009
Hello, is anyone there?
Authors: Rouse Robert W.
Published: April 2009

The author reflects on the future of the current economic crisis and what can be done to prevent a recurrence. But first he asks some tough questions. © 2009 Wiley Periodicals, Inc.
Paying attention in tough times
Authors: Reider Rob
Published: April 2009

Typically, the major concern for business owners and management is generating sales and increasing the bottom line. But in tough economic times like today, they must pay more attention to daily operations. They must look at all organizational functions and activities that help—or hinder—the effort to stay economical, efficient, and effective. The author leads us through a valuable operations checklist to help your company prosper in this difficult economic climate. © 2009 Wiley Periodicals, Inc.
Can the attorney‐client and work‐product privileges survive the annual audit?
Authors: Sonnier Blaise M. , Lassar Sharon S.
Published: April 2009

The IRS has been aggressively pursuing tax accrual workpapers in court. If the IRS prevails, corporate executives who rely on the legal advice of attorneys in making decisions may be providing litigation road maps to those who sue their companies.

This potential exposure of tax accrual workpapers is a wake‐up call for executives. They must review their procedures for seeking and securing legal advice. The authors reveal the vital steps management must take to protect privileged documents. © 2009 Wiley Periodicals, Inc.
New auditor risk–assessment guide
Authors: Weirich Thomas R. , Reinstein Alan
Published: April 2009

How should auditors judge risk, with the current economic turmoil and new regulations?

The authors give some much‐needed guidance for these complicated times. © 2009 Wiley Periodicals, Inc.
Auditor risk with mortgage‐backed M&As
Authors: Metcalf Lance B. , Liner Bryne J.
Published: April 2009

All professional service advisors have experienced the devastating impact of the credit crisis upon the economy. But auditors are particularly affected—especially by merger‐and‐acquisition (M&A) transactions for targets with mortgage‐backed securities. The authors discuss the current M&A environment for these transactions, look at auditors' risks, and examine possible solutions. © 2009 Wiley Periodicals, Inc.
How will valuation changes affect M&A deals?
Authors: Woodlock Peter , Peng Gang
Published: April 2009

In late 2007 and early 2008, both the Financial Accounting Standards Board and the International Accounting Standards Board issued separate statements on business combinations. There are a number of similarities between the two new standards, but differences do exist that could lead to dramatically different valuations of assets and liabilities in a merger‐and‐acquisition (M&A) deal. Deal makers must understand the differences in the two standards to decide how to structure any new deal. The authors take an in‐depth look at the issues involved. © 2009 Wiley Periodicals, Inc.
Resource consumption accounting: Manager‐focused management accounting
Authors: White Larry
Published: April 2009

This article presents resource consumption accounting (RCA), a management accounting methodology that focuses on the manager—not the external financial statement—as the primary user of its information. Based largely on German management accounting methods in use for at least 60 years, it incorporates the best insights of activity‐based costing (ABC), the theory of constraints (TOC), and traditional management accounting thinking. © 2009 Wiley Periodicals, Inc.
Cluster expansion models for flexible‐backbone protein energetics
Authors: Apgar James R. , Hahn Seungsoo , Grigoryan Gevorg , Keating Amy E.
Published: April 2009

Protein structure prediction and design often involve discrete modeling of side‐chain conformations on structural templates. Introducing backbone flexibility into such models has proven important in many different applications. Backbone flexibility improves model accuracy and provides access to larger sequence spaces in computational design, although at a cost in complexity and time. Here, we show that the influence of backbone flexibility on protein conformational energetics can be treated implicitly, at the level of sequence, using the technique of cluster expansion. Cluster expansion provides a way to convert structure‐based energies into functions of sequence alone. It leads to dramatic speed‐ups in energy evaluation and provides a convenient functional form for the analysis and optimization of sequence‐structure relationships. We show that it can be applied effectively to flexible‐backbone structural models using four proteins: α‐helical coiled‐coil dimers and trimers, zinc fingers, and Bcl‐xL/peptide complexes. For each of these, low errors for the sequence‐based models when compared with structure‐based evaluations show that this new way of treating backbone flexibility has considerable promise, particularly for protein design. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Computation of determinant expansion coefficients within the graphically contracted function method
Authors: Gidofalvi Gergely , Shepard Ron
Published: April 2009

Most electronic structure methods express the wavefunction as an expansion of N‐electron basis functions that are chosen to be either Slater determinants or configuration state functions. Although the expansion coefficient of a single determinant may be readily computed from configuration state function coefficients for small wavefunction expansions, traditional algorithms are impractical for systems with a large number of electrons and spatial orbitals. In this work, we describe an efficient algorithm for the evaluation of a single determinant expansion coefficient for wavefunctions expanded as a linear combination of graphically contracted functions. Each graphically contracted function has significant multiconfigurational character and depends on a relatively small number of variational parameters called arc factors. Because the graphically contracted function approach expresses the configuration state function coefficients as products of arc factors, a determinant expansion coefficient may be computed recursively more efficiently than with traditional configuration interaction methods. Although the cost of computing determinant coefficients scales exponentially with the number of spatial orbitals for traditional methods, the algorithm presented here exploits two levels of recursion and scales polynomially with system size. Hence, as demonstrated through applications to systems with hundreds of electrons and orbitals, it may readily be applied to very large systems. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
The effect of the sixth sulfur ligand in the catalytic mechanism of periplasmic nitrate reductase
Authors: Cerqueira N. M. F. S. A. , Gonzalez P. J. , Brondino C. D. , Romão M. J. , Romão C. C. , Moura I. , Moura J. J. G.
Published: April 2009

The catalytic mechanism of nitrate reduction by periplasmic nitrate reductases has been investigated using theoretical and computational means. We have found that the nitrate molecule binds to the active site with the Mo ion in the +6 oxidation state. Electron transfer to the active site occurs only in the proton‐electron transfer stage, where the MoV species plays an important role in catalysis. The presence of the sulfur atom in the molybdenum coordination sphere creates a pseudo‐dithiolene ligand that protects it from any direct attack from the solvent. Upon the nitrate binding there is a conformational rearrangement of this ring that allows the direct contact of the nitrate with MoVI ion. This rearrangement is stabilized by the conserved methionines Met141 and Met308. The reduction of nitrate into nitrite occurs in the second step of the mechanism where the two dimethyl‐dithiolene ligands have a key role in spreading the excess of negative charge near the Mo atom to make it available for the chemical reaction. The reaction involves the oxidation of the sulfur atoms and not of the molybdenum as previously suggested. The mechanism involves a molybdenum and sulfur‐based redox chemistry instead of the currently accepted redox chemistry based only on the Mo ion. The second part of the mechanism involves two protonation steps that are promoted by the presence of MoV species. MoVI intermediates might also be present in this stage depending on the availability of protons and electrons. Once the water molecule is generated only the MoVI species allow water molecule dissociation, and, the concomitant enzymatic turnover. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
CCL5 secreted by senescent aged fibroblasts induces proliferation of prostate epithelial cells and expression of genes that modulate angiogenesis
Authors: Eyman D. , Damodarasamy M. , Plymate S.R. , Reed M.J.
Published: April 2009

There is increased interest in the effects of secretory products from aged cells on promoting both benign and malignant cell growth. We identified a human fibroblast line, AG04382, from an aged donor that naturally demonstrated senescence‐associated features and whose conditioned media significantly induced proliferation of benign prostatic hyperplasia (BPH1) cells. Candidate cytokines mediating this effect were identified with protein arrays and validated by ELISA. We found that the AG04382 fibroblast line secreted high levels of CXCL5, CCL5, and CCL2, but relative to the other lines, its conditioned media was unique in its increased expression of CCL5. Blocking studies using specific antibodies against CXCL5, CCL5, and CCL2 in the conditioned media of AG04382 showed that only CCL5 contributed significantly to BPH1 proliferation. Stimulation of BPH1 cells with rhuCCL5 resulted in increased proliferation and migration, as well as significant changes in the expression of genes that influence angiogenesis. These data suggest that CCL5 is a candidate chemokine secreted by aged cells that promotes prostate growth and regulates angiogenesis. J. Cell. Physiol. 220: 376–381, 2009. © 2009 Wiley‐Liss, Inc.
Parameters of protection against ultraviolet radiation‐induced skin cell damage
Authors: Cao Cong , Wan Yinsheng
Published: April 2009

Epidemiological and experimental evidence has supported the notion that solar ultraviolet (UV) radiation is the leading cause of skin cell damage and skin cancer. Non‐melanoma skin cancer, one of the malignancies with the most rapidly increasing incidence, is suggested to be directly related to the total exposure to solar UV light. Over the past few years, the mechanisms of cellular responses to UV radiation have received unprecedented attention. Understanding how skin cells respond to UV radiation will undoubtedly help decipher what goes wrong in a variety of clinical skin disorders including skin cancer and will facilitate the development of novel therapeutic strategies. In the past decade, studies have established that UV radiation induces multifarious signal transduction pathways, some of which lead to apoptotic cell death, while others protect against this process. In this review, we summarize some of the most recent progresses regarding the involvement of multiple signal pathways in UV radiation‐induced apoptosis in skin cells, especially in keratinocytes. These pathways include pro‐apoptosis components such as MAPK, AMPK, and p53 as well as pro‐survival components, namely, AKT and mTORC complexes. J. Cell. Physiol. 220: 277–284, 2009. © 2009 Wiley‐Liss, Inc.
Influence of salinity on lead and cadmium accumulation by the salt cedar (Tamarix smyrnensis Bunge)
Authors: Manousaki Eleni , Kokkali Fotini , Kalogerakis Nicolas
Published: April 2009

BACKGROUND: The removal of heavy metals from polluted soils through the use of suitable plants has attracted much interest over recent decades. In this study Tamarix smyrnensis Bunge has been investigated for the characterization of its metal tolerance and ability to accumulate Pb and Cd, in order to evaluate its effectiveness as a cleanup tool for phytoextraction applications. For this purpose, two hydroponic experiments were performed, one with lead at concentration 100 ppm and a second with cadmium at concentration 5 ppm and at three different salt concentrations (0, 100, 200 mmol L−1 NaCl).

RESULTS: The experimental results showed that Pb and Cd accumulation in shoots ranged from 150–270 ppm and 7.5–42 ppm, respectively, and salinity was found to increase metal accumulation in shoots. However, the presence of high metal and salt concentrations affected negatively the health and finally the survival of the plants.

CONCLUSION: T. smyrnensis is neither a Pb nor a Cd hyperaccumulator; however, metal accumulation levels in shoots considered together with its high biomass production suggest that it could be used for phytoextraction applications. Furthermore, salinity has a positive influence on Pb and Cd accumulation in harvestable parts of the plant when it remains in low concentrations. Copyright © 2009 Society of Chemical Industry
Simultaneous 3D visualization and quantification of murine bone and bone vasculature using micro‐computed tomography and vascular replica
Authors: Schneider Philipp , Krucker Thomas , Meyer Eric , Ulmann‐Schuler Alexandra , Weber Bruno , Stampanoni Marco , Müller Ralph
Published: April 2009

Recent evidence suggests a close functional relationship between osteogenesis and angiogenesis as well as between bone remodeling and bone vascularization. Consequently, there is a need for visual inspection and quantitative analysis of the bone vasculature. We therefore adapted and implemented two different vascular corrosion casting (VCC) protocols using a polyurethane‐based casting resin in mice for a true three‐dimensional (3D), direct, and simultaneous measurement of bone tissue and vascular morphology by micro‐computed tomography (μCT). For assessment of vascular replicas at the level of capillaries, a vascular contrast perfusion (VCP) protocol was devised using a contrast modality based on a barium sulfate suspension in conjunction with synchrotron radiation (SR) μCT. The vascular morphology quantified using the VCP protocol was compared quantitatively with the results of a previously established method, where the vascular network of cortical bone was derived indirectly from cortical porosity. The presented VCC and VCP protocols have the potential of serving as a valuable method for concomitant 3D quantitative morphometry of the bone tissue and its vasculature. Microsc. Res. Tech. 2009. © 2009 Wiley‐Liss, Inc.
Proof of a conjecture on fractional Ramsey numbers
Authors: Brown Jason , Hoshino Richard
Published: April 2009

Jacobson, Levin, and Scheinerman introduced the fractional Ramsey function rf (a1, a2, …, ak) as an extension of the classical definition for Ramsey numbers. They determined an exact formula for the fractional Ramsey function for the case k=2. In this article, we answer an open problem by determining an explicit formula for the general case k>2 by constructing an infinite family of circulant graphs for which the independence numbers can be computed explicitly. This construction gives us two further results: a new (infinite) family of star extremal graphs which are a superset of many of the families currently known in the literature, and a broad generalization of known results on the chromatic number of integer distance graphs. © 2009 Wiley Periodicals, Inc. J Graph Theory 63: 164–178, 2010
The emergence of sociology from political economy in the United States: 1890 to 1940
Authors: Young Cristobal
Published: April 2009

Professional sociology in the U.S. began as a field area within economics, but gradually emerged as a separate discipline. Using new data on joint meetings and the separation of departments, I track interdisciplinary relations through three phases: sponsorship (1890–1905), collaboration (1905–1940), and disengagement (post‐1940). In the early years, sociology was mostly a branch of economics departments. With the formation of the American Sociological Society, relations with economics began to be more characterized by professionally autonomous collaboration. The 1920s saw a large wave of sociology departments separating from economics. Still, joint annual meetings (including joint presidential addresses) remained the norm until 1940. Paradigmatic conflict between institutional and neoclassical economists was the major force that sustained the economics–sociology collaboration. As institutionalism faded from the scene in the late 1930s, so went interdisciplinary contact. © 2009 Wiley Periodicals, Inc.
Synthesis of lead LFA‐1 antagonist [14C]spyrocyclic hydantoin
Authors: Tran Scott B. , Maxwell Brad D. , Chen Shiang‐Yuan , Bonacorsi Samuel J. , Leith Leslie , Ogan Marc , Rinehart J. Kent , Balasubramanian Balu
Published: April 2009

Radiolabelled drug lead candidate leukocyte function‐associated antigen 1 antagonist [14C]spyrocyclic hydantoin: 5‐(((5S,9R)‐9‐(4‐[14C]‐cyanophenyl)‐3‐(3,5‐dichlorophenyl)‐1‐methyl‐2,4‐dioxo‐1,3,7‐triazaspiro[4.4]nonan‐7‐yl)methyl)thiophene‐3‐carboxylic acid, 12, was conveniently prepared in three radiochemical steps from (5S,9R)‐tert‐butyl 9‐(4‐bromophenyl)‐3‐(3,5‐dichlorophenyl)‐1‐methyl‐2,4‐dioxo‐1,3,7‐triazaspiro[4.4]nonane‐7‐carboxylate 9. The radiochemical yield of 12 was 28.5% from the resolved bromide 9. The preparation of the racemic spyrocyclic hydantoin 3 was obtained via a [3+2]dipolar cycloaddition reaction between 2 and N‐benzyl‐N‐(methoxymethyl)trimethylsilylmethylamine. The introduction of [14C] cyanide was completed via a palladium (0) catalyzed reaction by the addition of Zn(14CN)2 to aryl bromide 9. The radiochemical and chiral purities of 12 determined by high‐performance liquid chromatography were 98.7 and 99.7%, respectively. The specific activity of 12 was 87.5 µCi/mg (48.6 mCi/mmol). Copyright © 2009 John Wiley & Sons, Ltd.
Gene expression analyses of neurons, astrocytes, and oligodendrocytes isolated by laser capture microdissection from human brain: Detrimental effects of laboratory humidity
Authors: Ordway Gregory A. , Szebeni Attila , Duffourc Michelle M. , Dessus‐Babus Sophie , Szebeni Katalin
Published: April 2009

Laser capture microdissection (LCM) is a versatile computer‐assisted dissection method that permits collection of tissue samples with a remarkable level of anatomical resolution. LCM's application to the study of human brain pathology is growing, although it is still relatively underutilized, compared with other areas of research. The present study examined factors that affect the utility of LCM, as performed with an Arcturus Veritas, in the study of gene expression in the human brain using frozen tissue sections. LCM performance was ascertained by determining cell capture efficiency and the quality of RNA extracted from human brain tissue under varying conditions. Among these, the relative humidity of the laboratory where tissue sections are stained, handled, and submitted to LCM had a profound effect on the performance of the instrument and on the quality of RNA extracted from tissue sections. Low relative humidity in the laboratory, i.e., 6–23%, was conducive to little or no degradation of RNA extracted from tissue following staining and fixation and to high capture efficiency by the LCM instrument. LCM settings were optimized as described herein to permit the selective capture of astrocytes, oligodendrocytes, and noradrenergic neurons from tissue sections containing the human locus coeruleus, as determined by the gene expression of cell‐specific markers. With due regard for specific limitations, LCM can be used to evaluate the molecular pathology of individual cell types in post‐mortem human brain. © 2009 Wiley‐Liss, Inc.
NOX2 mediates apoptotic death induced by staurosporine but not by potassium deprivation in cerebellar granule neurons
Authors: Guemez‐Gamboa Alicia , Morán Julio
Published: April 2009

Neuronal apoptotic death involves the participation of reactive oxygen species (ROS), but their sources have not been completely elucidated. Previous studies have demonstrated that the ROS‐producing enzyme NADPH oxidase is present in neuronal cells and that this enzyme could participate in the apoptotic neuronal death. Cerebellar granule neurons (CGN) undergo apoptosis when cells are transferred from a medium with 25 mM KCl (K25) to a 5 mM KCl (K5) medium or when they are treated with staurosporine (ST). Under these conditions, apoptotic death of CGN is dependent on ROS production. In this study, we evaluated the role of NOX2, an NADPH oxidase homolog, in the apoptotic death of CGN induced by two different conditions. In CGN from NOX2‐deficient (ko) mice, a significantly lower rate of apoptotic death occurs compared with wild‐type (wt) CGN. Also, caspase‐3 activation, NADPH oxidase activity, and superoxide anion production induced by ST were markedly lower in ko neurons than in wt CGN. In contrast to the case with ST, when CGN were treated with K5, no differences were observed between ko and wt cells in any of the parameters measured. However, all NADPH oxidase inhibitors tested noticeably reduced cell death and apoptotic parameters induced by K5 in both wt and ko CGN. These results suggest that NOX2 could be necessary for apoptotic death induced by ST, but not by K5, which could require other member of the NOX family in the apoptotic process. © 2009 Wiley‐Liss, Inc.
Effects of escitalopram on the regulation of brain‐derived neurotrophic factor and nerve growth factor protein levels in a rat model of chronic stress
Authors: Schulte‐Herbrüggen Olaf , Fuchs Eberhard , Abumaria Nashat , Ziegler Annerose , Danker‐Hopfe Heidi , Hiemke Christoph , Hellweg Rainer
Published: April 2009

Escitalopram (ES‐CIT) is a widely used, highly specific antidepressant. Until now there has been very little evidence on how this drug under pathological conditions affects an important feature within the pathophysiology of stress‐related disorders such as depression: the endogenous neurotrophins. By using a well‐characterized rat model in which chronic stress induces depressive‐like behavior, the levels of neurotrophins brain‐derived neurotrophic factor (BDNF) and nerve growth factor (NGF) were determined in representative brain regions and serum using a highly sensitive improved fluorometric two‐site ELISA system. There was a significant increase of BDNF in the left and right cortices after stress treatment (twofold increase) that was reversed by application of ES‐CIT. An ES‐CIT‐dependent NGF reduction in stressed rats was detectable in the right cortex only (P= 0.027). The left hippocampus revealed significantly higher amounts of BDNF (2.5‐fold increase) protein than the right hippocampus. These interhemispheric differences were unrelated to stress or ES‐CIT treatment in all animals. BDNF and NGF of the frontal cortex, cerebellum, and serum did not change between the study groups. There was a negative correlation between body weight and serum BDNF, independent of stress or ES‐CIT treatment. In conclusion, BDNF and NGF show substantial changes in this rodent model of chronic social stress, which is susceptible to antidepressant treatment with ES‐CIT and therefore may constitute a neurobiological correlate for the disease. © 2009 Wiley‐Liss, Inc.
Role of soluble CD14 in cerebrospinal fluid as a regulator of glial functions
Authors: Yin Guo Nan , Jeon Hyejin , Lee Shinrye , Lee Ho Won , Cho Je‐Yoel , Suk Kyoungho
Published: April 2009

Proteomic analysis of cerebrospinal fluid (CSF) samples derived from patients with Alzheimer's disease (AD) or Parkinson's disease (PD) was performed. On the basis of liquid chromatography–tandem mass spectrometry, two‐dimensional gel electrophoresis analysis, and Western blot validation, it was found that the level of soluble form of monocyte differentiation antigen CD14 precursor was elevated in CSF from AD or PD patients compared with normal subjects. The soluble CD14 protein and mRNA expression was detected in microglia cells, indicating that microglia may be a cellular source of soluble CD14 in CSF. Next, the role of soluble CD14 in the regulation of glial functions was investigated. Soluble CD14 inhibited lipopolysaccharide (LPS)‐ or LPS/interferon‐gamma‐induced nitric oxide production and cell death of microglia and astrocytes. Soluble CD14 suppressed glial neurotoxicity in a coculture of glia/neuroblastoma. In addition, soluble CD14 moderately enhanced phagocytic activity of microglia. These results suggest that microglia‐derived soluble CD14 is a candidate CSF biomarker for AD and PD, and the soluble CD14 may inhibit glial activation by interfering with LPS effects. © 2009 Wiley‐Liss, Inc.
Comparison of different geostatistical approaches to map climate variables: application to precipitation
Authors: Moral Francisco J.
Published: April 2009

The benefits of an integrated geographical information system (GIS) and a geostatistics approach to accurately model the spatial distribution pattern of precipitation are known. However, the determination of the most appropriate geostatistical algorithm for each case is usually neglected, i.e. it is important to select the best interpolation technique for each study area to obtain accurate results. In this work, the ordinary kriging (OK), simple kriging (SK) and universal kriging (universal kriging) methods are compared with three multivariate algorithms which take into account the altitude: collocated ordinary cokriging (OCK), simple kriging with varying local means (SKV) and regression‐kriging (RK). The different techniques are applied to monthly and annual precipitation data measured at 136 meteorological stations in a region of southwestern Spain (Extremadura). After carrying out cross‐validation, the smallest prediction errors are obtained for the three multivariate algorithms but, particularly, SKV and RK outperform collocated OCK, which needs a more demanding variogram analysis. These algorithms are easily implemented in a GIS, requiring the residual estimates and map algebra capability to generate the final maps. Results evidence the necessity of accounting for spatially dependent precipitation data and the collocated altitude, to accurately define monthly and annual precipitation maps. Copyright © 2009 Royal Meteorological Society
An error analysis for the hybrid gridding of Texas daily precipitation data
Authors: Rupp Andreas J. , Bailey Barbara A. , Shen Samuel S.P. , Lee Christine K. , Scott Strachan B.
Published: April 2009

This paper reports the error analysis results for the gridded daily precipitation data over the state of Texas of the United States from January 1, 1901 to December 31, 2000. The Global Daily Climatology Network dataset is used for both the data gridding and error analysis. The station data have been interpolated onto a 0.2° × 0.2° grid which starts at the base point (25°50′N, 106°38′W). The data gridding approach is a hybrid method, which is a blend of two simple methods: inverse distance weighting and nearest station assignment. Our gridding results are compared with those obtained by other gridding methods. The cross‐validation method is used for the error analysis. Our error analysis of the interpolated products includes not only the conventional errors, such as the mean bias error, but also the probabilistic distribution of the relative errors of precipitation frequency and the spatial distribution of a major Texas historical storm. The following results have been found: (1) a simple arithmetic average of station data usually overestimates Texas' average precipitation by 2.4 mm per day, (2) the relative error of the precipitation frequency follows a lognormal distribution, and (3) the hybrid gridding data do not have obvious bias and can reasonably display storm‐covered areas in Texas. The gridded data and error results are useful for the validation of climate models, calibration of satellite borne remote sensing devices, and numerous agricultural and hydrological applications. The statistical methods of our analysis and some of our results are applicable to other regions of the world. Copyright © 2009 Royal Meteorological Society
Modelling the atmospheric response over southern Africa to SST forcing in the southeast tropical Atlantic and southwest subtropical Indian Oceans
Authors: Hansingo K. , Reason C. J. C.
Published: April 2009

The sensitivity of the atmospheric circulation and rainfall over southern Africa to various regional sea surface temperature (SST) patterns observed during Benguela Niño events is investigated using an atmospheric general circulation model (AGCM). The model used is the United Kingdom Meteorological Office (UKMO) HadAM3 and experiments using idealizations of observed regional SST anomalies during various Benguela Niño events are performed. It is found that SST forcing in the tropical southeast Atlantic induces a regional baroclinic response and that a Benguela Niño is capable of forcing anomalous rainfall along the Angolan and northern Namibian coastal regions on its own, via changes in low level moisture convergence, uplift and evaporation over the SST forcing.

An experiment with the tropical southeast Atlantic SST anomaly shifted slightly further north produced a larger circulation and rainfall response in the model. Additional experiments with various SST anomalies in the southwest Indian Ocean combined with those in the southeast Atlantic were performed. These experiments are motivated by the fact that South Indian Ocean SST anomalies of varying signs often occur at the same time as Benguela Niño events. The results of these experiments suggest that, depending on its sign, magnitude and location, SST forcing from the southwest Indian Ocean may augment or oppose the southern African rainfall anomalies occurring during a Benguela Niño event to varying degrees. Copyright © 2009 Royal Meteorological Society
In situ measurement of transport between subchondral bone and articular cartilage
Authors: Pan Jun , Zhou Xiaozhou , Li Wen , Novotny John E. , Doty Stephen B. , Wang Liyun
Published: April 2009

Subchondral bone and articular cartilage play complementary roles in load bearing of the joints. Although the biomechanical coupling between subchondral bone and articular cartilage is well established, it remains unclear whether direct biochemical communication exists between them. Previously, the calcified cartilage between these two compartments was generally believed to be impermeable to transport of solutes and gases. However, recent studies found that small molecules could penetrate into the calcified cartilage from the subchondral bone. To quantify the real‐time solute transport across the calcified cartilage, we developed a novel imaging method based on fluorescence loss induced by photobleaching (FLIP). Diffusivity of sodium fluorescein (376 Da) was quantified to be 0.07 ± 0.03 and 0.26 ± 0.22 µm2/s between subchondral bone and calcified cartilage and within the calcified cartilage in the murine distal femur, respectively. Electron microscopy revealed that calcified cartilage matrix contained nonmineralized regions (∼22% volume fraction) that are either large patches (53 ± 18 nm) among the mineral deposits or numerous small regions (4.5 ± 0.8 nm) within the mineral deposits, which may serve as transport pathways. These results suggest that there exists a possible direct signaling between subchondral bone and articular cartilage, and they form a functional unit with both mechanical and biochemical interactions, which may play a role in the maintenance and degeneration of the joint. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1347–1352, 2009
Proteome analysis of Pithecellobium dulce seeds using two‐dimensional gel electrophoresis and tandem mass spectrometry
Authors: Sawasdipuksa Narumon , Sumner Lloyd W , Lei Zhentian , Sangvanich Polkit
Published: April 2009

BACKGROUND: Pithecellobium dulce Benth. belongs to the Leguminosae family, which contains several members that are important components of human diets owing to their high protein content and quality. In this study the seed proteins from P. dulce were separated and identified using two‐dimensional gel electrophoresis (2‐DE) and mass spectrometry respectively.

RESULTS: The 2‐DE protein map revealed a total of 317 distinct protein spots, including a cluster of about 12 proteins located in the region of pI 5–6 with molecular masses of 55–97 kDa that accounted for more than 50% of the total proteins. Ninety‐six of the most abundant protein spots were analysed using nano liquid chromatography/tandem mass spectrometry (LC/MS/MS), from which 27 were successfully identified through the query of acquired tandem mass spectral data used in MASCOT searching against a custom legume protein database. A further four proteins from the highly abundant protein cluster were putatively identified using mass spectrometry‐driven BLAST (MS‐BLAST) homology searches.

CONCLUSION: This research has generated a 2‐DE proteome reference map for P. dulce seeds and used LC/MS/MS to characterise the proteins. The identification of proteins from P. dulce was carried out using the sequence database successively for MASCOT and MS‐BLAST homology‐based searches. Copyright © 2009 Society of Chemical Industry
Preparative separation and enrichment of four taxoids from Taxus chinensis needles extracts by macroporous resin column chromatography
Authors: Sun Rui , Fu Kusng , Fu Yujie , Zu Yuangang , Wang Ying , Luo Meng , Li Shuangming , Luo Hao , Li Zhengnan
Published: April 2009

An environment‐friendly method was established for the preparative separation and enrichment of four taxoids, namely 10‐deacetylbaccatin III (10‐DAB III), 7‐xylosyl‐10‐deacetyltaxol (7‐xyl‐10‐DAT), cephalomannine and paclitaxel from Taxus chinensis needles extracts. Characteristics of seven widely used macroporous resins for four taxoids were compared, AB‐8 resin offered better adsorption and desorption capacities than others. AB‐8 resin column chromatography was used to study the desorption process for four taxoids. The optimum parameters for desorption were 30% ethanol 5 RV for removing impurities, following 15 RV for 10‐DAB III, after the desorption of impurities with 35% ethanol 10 RV, 45% ethanol 30 RV for 7‐xyl‐10‐DAT, then 65% ethanol 10 RV for cephalomannine and paclitaxel, the flow rate was 6 RV/h. After separation on AB‐8 resin column chromatography, the contents of 10‐DAB III, 7‐xyl‐10‐DAT, cephalomannine and paclitaxel in the product reached 4.58, 13.17, 1.36 and 3.08%, respectively, which were 7.63‐, 3.68‐, 6.18‐ and 6.55‐fold to those in T. chinensis needles extracts. The recovery yields were 94.96, 77.32, 88.09 and 95.25%. In general, the AB‐8 resin column chromatography has the advantages of lower cost, high efficiency and simple procedure. Therefore, it may provide scientific references for the preparative separation and enrichment of taxoids from other T. species.
Separation of peptide isomers and conformers by ultra performance liquid chromatography
Authors: Winter Dominic , Pipkorn Rüdiger , Lehmann Wolf D.
Published: April 2009

Peptide isomers are characterized by an identical brutto formula, so that their specific detection by LC‐MS/MS requires an individual LC retention time and/or an individual MS/MS spectrum. Mixtures of various classes of peptide isomers were analyzed by reversed phase nano ultra high performance liquid chromatography (UPLC)‐MS/MS. Gradient elution was performed with a water/acetonitrile/formic acid system. Using this solvent system and gradients of medium length (30 or 60 min), mixtures were analyzed composed of structural isomers of modified peptides, sequence isomers of unmodified peptides, peptide/isopeptide pairs, diastereomeric peptide pairs, and peptide conformers. The large majority of the peptide isomers analyzed could be completely separated due to the high resolving power of UPLC. For most isomers, the observed retention time differences significantly exceeded the corresponding baseline peak widths leading for several isomeric pairs to resolutions above 10. In addition, hints for a separation of peptide conformers were observed. Most of the peptides analyzed were of synthetic origin, so that their individual assignment in the UPLC‐MS/MS runs was straightforward. The relative elution order of numerous sets of peptide isomers is documented and discussed. The study highlights the important benefits of a high chromatographic separation power for the specificity of LC‐MS/MS in the field of analytical proteomics.
Rapid and efficient purification of naphthodianthrones from St. John's wort extract by using liquid–liquid extraction and SEC
Authors: Karioti Anastasia , Vincieri Franco F. , Bilia Anna R.
Published: April 2009

Hypericin and pseudohypericin, the main naphthodianthrones present in Hypericum species are among the most promising natural products, but the research concerning their biological activities is hindered by their low content in the plant. In this paper a method for the rapid isolation of hypericin and pseudohypericin from Hypericum perforatum hydro‐alcoholic dried extracts has been developed. Briefly, the method consists of a partition of the extract between organic and aqueous layers and further purification of the richest extract in naphthodianthrones with Sephadex LH‐20 column chromatography. A final separation of hypericin from pseudohypericin was achieved using Sephadex LH‐60 column chromatography. All partitions were carried out in triplicate and monitored by LC‐MS and NMR analyses. The best results were obtained by successive extraction with n‐hexane, Et2O and EtOAc. A three‐step fractionation resulted in 98% content in total naphthodianthrones. To the best of our knowledge this is the first report on the separation of hypericin from pseudohypericin using size exclusion chromatography.
Temperature and pH‐stability of commercial stationary phases
Authors: Teutenberg Thorsten , Hollebekkers Koen , Wiese Steffen , Boergers Andrea
Published: April 2009

In this paper, the temperature and pH stability of silica‐based RP stationary phases were investigated. Furthermore, nonsiliceous phases like a polymeric column based on polystyrene divinylbenzene and a polybutadiene coated zirconium dioxide column were also included. The columns were heated up to 150°C at dynamic conditions, which means that the eluent consisting of water and methanol (90:10, v/v) was continuously purged through the packed bed. After every 5 h, the columns were cooled down to room temperature and the efficiency was measured by injecting a test sample based on the Neue test. It could be shown that some stationary phases exhibited a very good temperature stability at the test conditions specified above.
Tarnish and corrosion evaluation of a blue gold‐based alloy
Authors: Carvalho O. , Soares D. , Fonseca A. , Silva F. S.
Published: April 2009

The use of some coloured gold alloys is dependent on the physical stability of the material when subjected to a corrosion media. This paper is concerned with the effect of two common detrimental environments (sweat and sulphuric solutions) on the stability of a blue gold‐base alloy. Changes in physical properties, namely colour and brightness, were evaluated with time. It was observed that, for sulphuric solution, significant changes were obtained even for small immersion times. For the artificial sweat solution, changes occur, but the alloy is significantly more resistant. The alloy corrosion mechanisms are presented for both types of solutions. The products of corrosion were characterized by optical and SEM/EDS microscopy and by XPS spectroscopy. A comparison of the corrosion mechanisms, between the two immersion solutions, is also presented.
Electrochemical response of amorphous and devitrified Al‐Ni‐La‐X (X = Ag, Cu) alloys
Authors: Roy A. , Mandhyan A. K. , Sahoo K. L. , Banhart J. , Chattoraj I.
Published: April 2009

The electrochemical response of melt‐spun Al‐Ni‐La alloys with partial substitution of Ni after different stages of devitrification was studied. The base alloy was found to have the best corrosion resistance. It was observed that primary crystallization caused minimal deterioration in the corrosion resistance of the base alloy as compared to its amorphous state. The substitute alloys had different corrosion resistance dependent on the substituting element with the Ag containing alloy having the least resistance. This could be attributed to the operation of local galvanic cells, enhanced by chemical heterogeneities in the alloys. Secondary crystallization caused a reduction in the corrosion resistance of all the alloys due to the creation of intermetallic phases that increased the galvanic activity.
Analysis of electrochemical noise of X70 steel in Ku'erle soil by cluster analysis
Authors: Huang J.Y. , Qiu Y.B. , Guo X.P.
Published: April 2009

Electrochemical noise (EN) technique was employed to study the corrosion behaviors of the X70 pipeline steel in the Xinjiang Ku'erle saline soil (moisture content 1.04%) during the initial corrosion period (0–7 days). The obtained EN data were analyzed by principal component analysis (PCA), hierarchical agglomerative cluster analysis (HACA) and wavelet analysis (WA). After the PCA applied, the potential standard deviation ($\sigma _E$) and mean value ($\overline E$) as well as current mean value ($\overline I$) were considered as the descriptors to characterize EN distribution. Then, using $\sigma _E$, $\overline E$, and $\overline I$ as variables, three different corrosion states of the local corrosion in the soil can be classified clearly by the HACA, including instable germination state, quick development state, and stable development state. According to the WA, the different characteristics of the three corrosion stages have been further proved. The results show that the PCA–HACA method should be successful for the analysis of EN signals from the soil corrosion system.
Influence of rare earth element Ce and La addition on corrosion behavior of AZ91 magnesium alloy
Authors: Liu W. , Cao F. , Zhong L. , Zheng L. , Jia B. , Zhang Z. , Zhang J.
Published: April 2009

Two types of AZ91 magnesium alloys containing rare earth element Ce or La were fabricated. Hydrogen evolution and electrochemical tests were carried out to evaluate the corrosion behavior of new AZRE (RE = Ce or La) and AZ91 alloys in 3.5% NaCl solutions (pH 6.50). Various corrosion rate tests indicated that addition of RE obviously enhanced corrosion resistance of AZ91 magnesium alloy. The optimal content of RE was 0.92% for Ce and 0.66% for La. Scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and low‐angle X‐ray diffraction (XRD) were used to characterize the effect of RE addition on microstructure and corrosion product film of AZ91 magnesium alloy. The refined β phase and formation of γ phase in AZRE alloy were observed by SEM, which resulted in the improvement of corrosion resistance due to the depression of microgalvanic couples. Moreover, the enhanced protective effectiveness of corrosion products was another reason for the improved corrosion resistance.
Electrochemical corrosion response of a low carbon heat treated steel in a NaCl solution
Authors: Osório W. R. , Peixoto L. C. , Garcia L. R. , Garcia A.
Published: April 2009

Dual‐phase (DP) steels are produced from a specific heat treatment procedure and have recently emerged as a potential class of engineering materials for a number of structural and automobile applications. Such steels have high strength‐to‐weight ratio and reasonable formability. The present study aims to investigate the effects of four different and conventional heat treatments (i.e., hot rolling, normalizing, annealing, and intercritical annealing) on the resulting microstructural patterns and on the electrochemical corrosion behavior. Electrochemical impedance spectroscopy (EIS) and Tafel plots were carried out on heat treated steel samples in a 0.5 M NaCl solution at 25 °C with neutral pH. An equivalent circuit analysis was also used to provide quantitative support for the discussions. The normalizing and the annealing heat treatments have provided the highest and the lowest corrosion resistances, respectively. The intercritical annealing and as‐received (hot rolled) low carbon steel samples have shown similar corrosion behavior. Although a deleterious effect on the corrosion resistance has been verified for DP steel due to the residual stress from the martensite formation, it combines good mechanical properties with intermediate electrochemical corrosion resistance.
Corrosion characteristics of electroless Ni–P coating in sulfur‐bearing solution
Authors: Wu Y. H. , Liu T. M. , Luo S. X.
Published: April 2009

The corrosion behaviors of electroless Ni–P coatings deposited on carbon steel in sulfur‐bearing solutions were investigated by weight gain test and scanning electron microscopy. The results indicate that the corrosion rate of electroless Ni–P coating was directly related to the sulfur content, immersion time, and test temperature. The corrosion rate increased with the prolonged immersion time. Increasing the temperature can markedly increase the corrosion rate of electroless Ni–P coating. The electroless Ni–P coating had a better corrosion resistance than 316L stainless steel against Cl− corrosion in sulfur‐bearing solution.
Molecular Shapes of Monosubstituted Polyacetylenes in their Liquid Crystalline Phases
Authors: Liu Kai‐Peng , Yu Zhen‐Qiang , Liu Jia‐Hao , Chen Er‐Qiang
Published: April 2009

In this short review, we discuss the molecular shapes of monosubstituted polyacetylenes (MSPAs) in their liquid crystalline (LC) phases. Their rigid backbone with high stereoregularity can endow MSPAs with significant shape persistency, which largely determines their LC structures. Helical cis‐cisoidal and cis‐transoidal MSPAs render rod‐like shapes and can form columnar LC (Φ) phases. In the smectic LC (Sm) phases of MSPAs with mesogenic side‐chains, the main chain, with trans‐cisoidal, trans‐transoidal or extended cis‐transoidal conformation, is in fact largely coplanar with the side‐chains, resulting in a sheet‐like molecular shape. From a simple geometric point of view, the rod‐ or sheet‐like MSPA molecules serve as the building block of their LC phases.

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