bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermodynamic cloud point assays
Authors: Bergbreiter David E. , Fu Hui 
Published: November 2007

AbstractAnalysis of cloud points and clouding curves by varying heating rates using a commercially available automated melting point apparatus is a method to obtain a corrected cloud point for polymers that have a lower critical solution temperature (LCST). Such assays also provide information about the effects of varying heating rates on LCSTs and similar stimuli‐responsive phase separation behavior. This melting point apparatus makes it experimentally simple to conduct such assays that probe the effect of varying heating rates, the effect of polymer structure, and the effect of solution components on the breadth and progress of the phase transition process over a wide temperature range. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 186–193, 2008
Non‐Axial Stress State in a Model Silo Generated by Eccentric Filling and Internal Inserts
Authors: Molenda Marek , Montross Michael D. , Horabik Józef 
Published: November 2007

AbstractDangerous nonuniformity of grain loads within a silo may be caused by eccentric discharge, eccentric loading, eccentric structural members fastened to the wall, geometrical imperfections or nonuniformity of the frictional conditions. Some of these effects have been quantified based on testing corrugated‐walled, flat floor model silos filled with wheat. In this type of silo, filling above a height to diameter ratio of H/D = 2.0 resulted in mixed flow (following the terminology of Eurocode 1) where grain slides along the wall during discharge above the effective transition and remains stagnant below the effective transition – located at H/D = ca. 0.7 (more details in [1]).The degree of load asymmetry due to eccentric filling is demonstrated and compared to the worst case observed, i.e., eccentric discharge through an orifice located at a distance of 0.7 of the floor radius from the silo centerline. The presence of a nonsymmetric flow obstruction on the silo wall is found to cause dangerous local loads similar to eccentric discharge. Considerable nonuniformity in the load is observed during testing of a cylindrical obstruction immersed in grain supported on the silo floor with its axis parallel to the silo centerline. The mechanisms of these phenomena are still poorly understood, and a satisfactory theoretical description cannot be given.
Preliminary Experimental Analysis of a Spiral Jet Mill Performance
Authors: Katz Avi , Kalman Haim 
Published: November 2007

AbstractJet mills are common devices used in industry for the fine milling of dry particulate materials. The size reduction is caused by repeated impaction events between particles. Although many parameters affect the performance of a jet‐mill, only a few of them have been investigated by researchers to date. Furthermore, the published investigations test only a few materials. In order to bridge the knowledge gaps which exist, a new experimental apparatus was designed and constructed to enable experiments involving as many influencing parameters as possible. The new apparatus enables changing of the material feeding, mass flow rate, air flow rate, nozzle parameters (velocity, diameter, angle, number and shape), grinding chamber height and the classifier orientation. In this paper, preliminary experimental results concerning a number of the aforementioned parameters and their effect on the mill performance are presented.
Loads on Support Structural Elements Buried in Stockpiles
Authors: Roberts Alan W. 
Published: November 2007

AbstractThe paper presents a theory, combined with design equations, to compute the loads on structural elements, such as conveyor trestle legs or support columns buried in bulk solid storage systems such as stock piles. The stress conditions in the stored bulk solid in the immediate region of the buried structural element are shown to be a combination of active and passive stress states which are dependent on the method of filling and reclaim employed and the flow properties of the bulk solid. The theory examines the various loading conditions focusing on the determination of the lateral or bending load distribution as well as the compressive, in‐plane shear traction loads which may influence the buckling effect in buried structural support columns. The paper is illustrated by reference to a case study involving vertical support columns in a large bulk fertilizer shed. Experimental results performed on a small scale model of the bulk fertilizer facility are shown to confirm the predicted results.
On choosing the right ether for peptide precipitation after acid cleavage
Authors: de La Torre Beatriz G. , Andreu David 
Published: November 2007

AbstractMethyl tert‐butyl ether (MTBE) and diethyl ether (DEE) tend to be regarded as interchangeable for the ‘cold ether’ workup concluding the final acidolytic cleavage and deprotection step of solid‐phase peptide syntheses. However, the use of MTBE to precipitate peptides from strong acid solutions is shown to give rise to t‐butyl alkylation byproducts, readily detectable by MALDI‐TOF MS. The problem can attain undesirable dimensions in the cleavage of peptide resins containing high proportions of aromatic residues, particularly in peptide nucleic acid (PNA) syntheses. In those cases, DEE workup is advisable, as it consistently leads to cleaner products. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Detection, characterization, and quantification of resveratrol glycosides in transgenic arabidopsis over‐expressing a sorghum stilbene synthase gene by liquid chromatography/tandem mass spectrometry
Authors: Lo Clive , Le Blanc J. C. Yves , Yu Christine K. Y. , Sze K. H. , Ng Dominic C. M. , Chu Ivan K. 
Published: November 2007

AbstractTransgenic Arabidopsis plants were analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS) to investigate the glycosylation patterns of resveratrol derived from expression of a sorghum stilbene synthase gene. In negative ionization mode, the different resveratrol derivatives fragmented to yield the diagnostic deprotonated resveratrol ion at m/z 227.2. The use of precursor ion scanning led to the identification of precursor ions for different resveratrol glycosides through rapid differentiation from other phytochemical constituents. Structural information was generated simultaneously from the low‐collision‐energy product ion spectra using hybrid linear ion‐trap mass spectrometry. Three additional resveratrol‐related metabolites – a resveratrol diglucoside (M1) and trans‐ and cis‐resveratrol acetylhexosides (M2 and M3) – were detected in the crude plant extracts. The identities of M1, M2, and M3 were confirmed by accurate mass analysis on a quadrupole time‐of‐flight mass spectrometer as well as β‐glucosidase digestion or UV‐induced isomerization. Quantitative analyses by LC/MS in multiple reaction monitoring mode revealed that resveratrol diglucoside and cis‐resveratrol acetyhexoside accumulated up to 2.79 and 10.38 µg/g, respectively, while trans‐resveratrol acetylhexoside was barely detectable. This study demonstrated the power of the hybrid linear ion‐trap technology for simultaneous profiling and structural characterization of stilbene‐related metabolites, which would be useful to understand how resveratrol is modified in sorghum and other plants. Copyright © 2007 John Wiley & Sons, Ltd.
Feasibility Study of Safe Breast Conservation in Large and Locally Advanced Cancers with Use of Radiopaque Markers to Mark Pre‐Neoadjuvant Chemotherapy Tumor Margins
Authors: Aggarwal Vivek , Agarwal Gaurav , Lal Punita , Krishnani Narendra , Mishra Anjali , Verma Ashok K. , Mishra Saroj K. 
Published: November 2007

AbstractBackgroundThe lack of objective documentation of pre‐neoadjuvant chemotherapy (NACT) margins after chemotherapy is a major constraint in performing safe breast‐conserving surgery (BCS) in patients with locally advanced breast cancer (LABC). Using a novel method of marking pre‐NACT tumor margins with indigenous silver wire markers, this prospective pilot study attempted to assess the feasibility of safe BCS in LABC patients by performing excision wide of the marked pre‐NACT margins.MethodsLABC patients had sterile silver wire markers placed at all tumor margins percutaneously. Patients were then treated with NACT followed by wide local excision (WLE) incorporating pre‐NACT margins (ex vivo on mastectomy specimen or in vivo in patients opting for BCS). The histology of the margins wide of the post‐WLE cavity (pre‐NACT) and post‐NACT tumor was used to assess adequate disease clearance and safety of BCS.ResultsAltogether, 40 stage III breast cancer patients (mean tumor size 7.9 cm) were studied; none had marker‐related complications. Following NACT, the tumor size assessed by markers showed average regression by 1.5 cm. The pre‐NACT margins were histologically negative in 95% of the surgical specimens. In 2 (5%) patients both pre‐NACT and post‐NACT margins were positive; post‐NACT margins were infiltrated in 14 (35%).ConclusionsThe post‐NACT WLE that is wide of the marked pre‐NACT margins can achieve uninfiltrated margins in 95% of cases. If post‐NACT margins are used to guide the WLE, 35% patients would have infiltrated margins, some of which would remain undetected, putting patients at high risk of local recurrence. This novel indigenous method of identifying tumor margins with sterile silver wire markers is safe, inexpensive, practical, and effective; and it may help perform safe BCS in a large proportion of LABC patients.
The Other Side of the Coin: Perceived Positive Effects of Illness in Women Following Acute Myocardial Infarction
Authors: Norekvål Tone M. , Moons Philip , Hanestad Berit R. , Nordrehaug Jan E. , Wentzel-Larsen Tore , Fridlund Bengt 
Published: November 2007

Background: Although myocardial infarction (MI) is linked with both physical and psychological impairments, the possibility of patients also experiencing positive outcomes of MI has received far less attention in research and in clinical practice. In particular, this aspect has been under-investigated in older persons and in women. Aim: The purpose of this study was to investigate possible positive effects of illness, describe the patient characteristics and explore the nature and frequency of these effects in older women after MI. Methods: A cross-sectional postal survey was conducted in 145 women aged 62–80 years, three months to five years after MI. Self-reported socio-demographic and clinical data, in addition to data from medical records, were collected. A single-item question – “All in all, was there anything positive about experiencing an MI?” – was used to assess positive effects of illness, in addition to an open-ended question on the nature of possible positive effects. Results: A majority of the women (65%) reported positive effects from their MI experience. The women perceiving positive effects did not differ from those who did not on socio-demographic and clinical variables, except for being older ( p = 0.007) and less often readmitted ( p = 0.029). The groups did not differ significantly as to disease severity and time since MI. Four themes emerged from the open-ended questioning on the nature of perceived positive effects of the illness: Appreciating Life (55%), Getting Health Care (42%), Making Lifestyle Changes (36%), and Taking More Care of Self and Others (29%). Conclusions: The findings contribute to a more complete picture of psychosocial issues in women after MI by providing evidence that positive effects are often experienced despite physical limitations. Nurses may use this knowledge as a tool in patient education and communication, although further research is needed to determine the most optimal interventions for MI patients.
Technological Change and the Form of Science Research Teams: Dealing with the Digitals
Authors: Meyer Eric T. 
Published: November 2007

Abstract
During the late 1990s, photography moved from being a primarily analogue medium to being an almost entirely digital medium. The development of digital cameras and software for working with photographs has led to the wholesale computerization of photography in many different domains. This paper reports on the findings of a study of the social and organizational changes experienced by marine mammal scientists who have changed from film‐based photography to digital photography. This technical change might be viewed as a simple substitution of a digital for an analogue camera, with little significance for how scientists do what they do. However, a perspective anchored in social informatics leads to the expectation that such incremental technical changes can have significant outcomes, changing not only how scientists work, but also the outcomes of their research. This present study finds that key consequences of this change have been the composition of the personnel working on the scientific research teams for marine biology projects and the ways in which these scientists allocate their time.
The Use of Touch‐Screen Technology for Health‐Related Information in Indigenous Communities: Some Economic Issues
1
Authors: Doessel D. P. , Travers Helen , Hunter Ernest 
Published: November 2007

Abstract
The low health status of indigenous communities in Australia, and other countries, has been a continuing societal problem. One way to improve health status involves the provision of health‐related information. Computer‐based systems offer new ways to provide such information: thus their application can be seen as process innovations. This paper describes the use of touch‐screen technology to present health information in a culturally relevant fashion for Aboriginal and Torres Strait Islanders in Queensland, Australia. Touch‐screen kiosks incorporate both computer hardware and software. The paper also outlines some of the key economic concepts relevant to an economic analysis of an information system employing touch‐screen technology. It is shown that the economic analysis involves a two‐stage process, and it is somewhat more complex than setting up an Internet website.
Review Article: The Rise of Studying Happiness, but what of the Shadow of Unhappiness from Mental Illness?
1
Authors: Doessel D. P. 
Published: November 2007

Abstract
This essay is concerned with describing some issues associated with a relatively recent development in economics, viz. the economics of happiness literature. After providing a very brief account of the history of the concept of happiness, and the recent literature in economics, the focus turns to two issues that have been relatively neglected. First, there has been little attention in this recent literature to the concept of virtue or a flourishing life, or a moral disposition to happiness. Second, it is argued that the focus on aggregate happiness for a society in general may be misplaced: focus on subgroups, such as the mentally ill, may be more appropriate.
Estimating node degree in bait-prey graphs
Authors: Scholtens Denise , Chiang Tony , Huber Wolfgang , Gentleman Robert 
Published: November 2007

Abstract
Motivation: Proteins work together to drive biological processes in cellular machines. Summarizing global and local properties of the set of protein interactions, the interactome, is necessary for describing cellular systems. We consider a relatively simple per-protein feature of the interactome: the number of interaction partners for a protein, which in graph terminology is the degree of the protein.
Results: Using data subject to both stochastic and systematic sources of false positive and false negative observations, we develop an explicit probability model and resultant likelihood method to estimate node degree on portions of the interactome assayed by bait-prey technologies. This approach yields substantial improvement in degree estimation over the current practice that naïvely sums observed edges. Accurate modeling of observed data in relation to true but unknown parameters of interest gives a formal point of reference from which to draw conclusions about the system under study.
Availability: All analyses discussed in this text can be performed using the ppiStats and ppiData packages available through the Bioconductor project (http://www.bioconductor.org).
Contact: dscholtens@northwestern.edu
Supplementary information: Supplementary data are available at Bioinformatics online.
Saturation mutagenesis of Asn152 reveals a substrate selectivity switch in P99 cephalosporinase
Authors: Lefurgy Scott T. , de Jong René M. , Cornish Virginia W. 
Published: November 2007

AbstractIn class C β‐lactamases, the strictly conserved Asn152 forms part of an extended active‐site hydrogen‐bonding network. To probe its role in catalysis, all 19 mutants of Enterobacter cloacae P99 cephalosporinase Asn152 were simultaneously constructed and screened in Escherichia coli for their in vivo activity. The screen identified the previously uncharacterized mutants Asn152Ser, Asn152Thr, and Asn152Gly, which possess significant activity and altered substrate selectivity. In vitro measurement of Michaelis‐Menten kinetic constants revealed that the Asn152Ser mutation causes a selectivity switch for penicillin G versus cefoxitin. Asn152Thr showed a 63‐fold increase in kcat for oxacillin, a slow substrate for wild‐type cephalosporinase. The results contribute to a growing body of data showing that mutation of highly conserved residues in the active site can result in substrate selectivity changes. The library screening method presented here would be applicable to substrate selectivity determination in other readily screenable enzymes.
Large‐scale preparation of the homogeneous LolA–lipoprotein complex and efficient in vitro transfer of lipoproteins to the outer membrane in a LolB‐dependent manner
Authors: Watanabe Shoji , Oguchi Yuki , Yokota Naoko , Tokuda Hajime 
Published: November 2007

AbstractAn ATP‐binding cassette transporter LolCDE complex of Escherichia coli releases lipoproteins destined to the outer membrane from the inner membrane as a complex with a periplasmic chaperone, LolA. Interaction of the LolA–lipoprotein complex with an outer membrane receptor, LolB, then causes localization of lipoproteins to the outer membrane. As far as examined, formation of the LolA–lipoprotein complex strictly depends on ATP hydrolysis by the LolCDE complex in the presence of LolA. It has been speculated, based on crystallographic and biochemical observations, that LolA undergoes an ATP‐dependent conformational change upon lipoprotein binding. Thus, preparation of a large amount of the LolA–lipoprotein complex is difficult. Moreover, lipoproteins bound to LolA are heterogeneous. We report here that the coexpression of LolA and outer membrane‐specific lipoprotein Pal from a very efficient plasmid causes the unusual accumulation of the LolA–Pal complex in the periplasm. The complex was purified to homogeneity and shown to be a functional intermediate of the lipoprotein localization pathway. In vitro incorporation of Pal into outer membranes revealed that a single molecule of LolB catalyzes the incorporation of more than 100 molecules of Pal into outer membranes. Moreover, the LolB‐dependent incorporation of Pal was not affected by excess‐free LolA, indicating that LolB specifically interacts with liganded LolA. Finally, the LolB depletion caused the accumulation of a significant amount of Pal in the periplasm, thereby establishing the conditions for preparation of the homogeneous LolA–lipoprotein complex.
Characterization of the binding surface of the translocated intimin receptor, an essential protein for EPEC and EHEC cell adhesion
Authors: Ross Nathan T. , Miller Benjamin L. 
Published: November 2007

AbstractThe translocated intimin receptor (TIR) of enteropathogenic and enterohemorrhagic Escherichia coli (EPEC and EHEC) is required for EPEC and EHEC infections, which cause widespread illness across the globe. TIR is translocated via a type‐III secretion system into the intestinal epithelial cell membrane, where it serves as an anchor for E. coli attachment via its binding partner intimin. While many aspects of EPEC and EHEC infection are now well understood, the importance of the intermolecular contacts made between intimin and TIR have not been thoroughly investigated. Herein we report site‐directed mutagenesis studies on the intimin‐binding domain of EPEC TIR, and how these mutations affect TIR‐intimin association, as analyzed by isothermal titration calorimetry and circular dichroism. These results show how two factors govern TIR's binding to intimin: A three‐residue TIR hot spot is identified that largely mediates the interaction, and mutants that alter the β‐hairpin structure of TIR severely diminish binding affinity. In addition, peptides incorporating key TIR residues identified by mutagenesis are incapable of binding intimin. These results indicate that hot spot residues and structural orientation/preorganization are required for EPEC, and likely EHEC, TIR‐intimin binding.
The Staphylococcus aureus extracellular adherence protein (Eap) adopts an elongated but structured conformation in solution
Authors: Hammel Michal , Němeček Daniel , Keightley J. Andrew , Thomas George J. , Geisbrecht Brian V. 
Published: November 2007

AbstractThe extracellular adherence protein (Eap) of Staphylococcus aureus participates in a wide range of protein–protein interactions that facilitate the initiation and dissemination of Staphylococcal disease. In this report, we describe the use of a multidisciplinary approach to characterize the solution structure of full‐length Eap. In contrast to previous reports suggesting that a six‐domain isoform of Eap undergoes multimerization, sedimentation equilibrium analytical ultracentrifugation data revealed that a four‐domain isoform of Eap is a monomer in solution. In vitro proteolysis and solution small angle X‐ray scattering studies both indicate that Eap adopts an extended conformation in solution, where the linkers connecting sequential EAP modules are solvent exposed. Construction of a low‐resolution model of full‐length Eap using a combination of ab initio deconvolution of the SAXS data and rigid body modeling of the EAP domain crystal structure suggests that full‐length Eap may present several unique concave surfaces capable of participating in ligand binding. These results also raise the possibility that such surfaces may be held together by additional interactions between adjacent EAP modules. This hypothesis is supported by a comparative Raman spectroscopic analysis of full‐length Eap and a stoichiometric solution of the individual EAP modules, which indicates the presence of additional secondary structure and a greater extent of hydrogen/deuterium exchange protection in full‐length Eap. Our results provide the first insight into the solution structure of full‐length Eap and an experimental basis for interpreting the EAP domain crystal structures within the context of the full‐length molecule. They also lay a foundation for future studies into the structural and molecular bases of Eap‐mediated protein–protein interactions with its many ligands.