bluuebunny/crossref_metadata_2025 huggingface dataset:
Parathyroid hormone and its effects on dental tissues
Authors: Aggarwal P , Zavras A
Published: August 2011

Oral Diseases (2011) 18, 48–54

In the current era, various pharmacological agents exist for osteoporosis management, and synthetic parathyroid hormone (PTH) (Teriparatide, Forteo) is one of the treatment options. Depending on the timing of administration, PTH has a unique ability to cause both bone apposition and bone resorption. This review focuses on the effects of PTH on the bone, specifically the jaw bones mandible and maxilla. The article briefly describes the fundamental mechanism of PTH action at the molecular level, as well as in experimental animals and in humans. It differentiates intermittent administration of PTH, especially at doses tolerated by humans that increase bone strength and prevent bone fractures, from continuous use that may lead to bone loss. In particular, it shows how intermittent administration of PTH can play a significant role in periodontal repair and implant success via stimulation of bone mineral content especially in the pre‐alveolar region.
Influences of watershed geomorphology on extent and composition of riparian vegetation
Authors: Engelhardt Blake M. , Weisberg Peter J. , Chambers Jeanne C.
Published: August 2011

Question

How strongly do watershed morphometry and geology influence the extent and composition of vegetation along riparian corridors?

Location

Eighteen upland watersheds in central Nevada, USA.

Methods

Watershed (drainage basin) morphometry and geology were derived from digital data sets (DEMs and geologic maps). Riparian corridors were classified into five vegetation types (riparian forest, riparian shrub, wet/mesic meadow, dry meadow and shrub dry meadow) using high‐resolution aerial photography. Regression and multivariate analyses were used to relate geomorphic characteristics to riparian vegetation extent and composition.

Results

Riparian extent ranged from 0.4% to 3.6% of watershed area, was positively related to percentage intrusive bedrock and drainage density, and was negatively related to percentage carbonate bedrock and relative stream power. Riparian forest and shrub types occupied more than 75% of the riparian corridor in 12 of 18 watersheds; meadow types comprised a smaller proportion. Watershed size, topography and geology were important in predicting riparian composition. Riparian forest and shrub types were more abundant in small, rugged watersheds of high relief. Meadow types were more abundant in large, low gradient and less rugged watersheds. The importance of woody vegetation increased with more volcanic and intrusive bedrock, whereas meadow vegetation increased with increasing alluvium, carbonate and metasedimentary rock types.

Conclusions

Watershed geomorphology significantly constrains extent and abundance of woody versus herbaceous vegetation within the riparian corridor. Watershed variables related to riparian vegetation are likely indicators of run‐off regimes or water and sediment transport. Consideration of relationships between watershed‐scale geomorphology and riparian vegetation can improve prediction and inform restoration efforts.
Proteomic reactors and their applications in biology
Authors: Zhou Hu , Ning Zhibin , Wang Fangjun , Seebun Deeptee , Figeys Daniel
Published: August 2011

Proteomic analysis requires the combination of an extensive suite of technologies including protein processing and separation, micro‐flow HPLC, MS and bioinformatics. Although proteomic technologies are still in flux, approaches that bypass gel electrophoresis (gel‐free approaches) are dominating the field of proteomics. Along with the development of gel‐free proteomics, came the development of devices for the processing of proteomic samples termed proteomic reactors. These microfluidic devices provide rapid, robust and efficient pre‐MS sample procession by performing protein sample preparation/concentration, digestion and peptide fractionation. The proteomic reactor has advanced in two major directions: immobilized enzyme reactor and ion exchange‐based proteomic reactor. This review summarizes the technical developments and biological applications of the proteomic reactor over the last decade.
Assessing the patterns of linkage disequilibrium in genic regions of the human genome
Authors: Sun Peng , Zhang Ruijie , Jiang Yongshuai , Wang Xing , Li Jin , Lv Hongchao , Tang Guoping , Guo Xiaodan , Meng Xianwen , Zhang Haikun , Zhang Ruimin
Published: August 2011

We used the genotyping data generated by the International HapMap Project to study the patterns of linkage disequilibrium (LD) in human genic regions. LD patterns for 11 998 genes from 11 HapMap populations were identified by analyzing the distribution of haplotype blocks. The genes were prioritized using LD levels. The results showed that there were significant differences in the degree of LD between genes. Genes with high or low LD (the upper and lower quartiles of the LD levels) fell into different Gene Ontology functional categories. The high LD genes clustered preferentially in the metabolic process, macromolecule localization and cell‐cycle categories, whereas the low LD genes clustered in the developmental process, ion transport, and immune and regulation system categories. Furthermore, we subdivided the genic region into 3′‐UTR, 5′‐UTR and CDS (coding region), and compared the different LD patterns in these subregions. We found that the LD patterns in low LD genes had a more interspersed block structure compared with the high LD genes. This was especially true in the CDS and 5′‐UTR. The extent of LD was somewhat higher in 5′‐UTRs compared with 3′‐UTRs for both high and low LD genes. In addition, we assessed the overlap for the intragenic LD regions and found that the LD regions in high LD genes were more consistent among populations. Comprehensive information about the distribution of LD patterns in gene regions in populations may provide insights into the evolutionary history of humans and help in the selection of biomarkers for disease association studies.
Barnase and binase: twins with distinct fates
Authors: Ulyanova Vera , Vershinina Valentina , Ilinskaya Olga
Published: August 2011

RNases are enzymes that cleave RNAs, resulting in remarkably diverse biological consequences. Many RNases are cytotoxic. In some cases, they attack selectively malignant cells triggering an apoptotic response. A number of eukaryotic and bacterial RNase‐based strategies are being developed for use in anticancer and antiviral therapy. However, the physiological functions of these RNases are often poorly understood. This review focuses on the properties of the extracellular RNases from Bacillus amyloliquefaciens (barnase) and Bacillus intermedius (binase), the characteristics of their biosynthesis regulation and their physiological role, with an emphasis on the similarities and differences. Barnase and binase can be regarded as molecular twins according to their highly similar structure, physical–chemical and catalytic properties. Nevertheless, the ‘life paths’ of these enzymes are not the same, as their expression in bacteria is controlled by diverse signals. Binase is predominantly synthesized under phosphate starvation, whereas barnase production is strictly dependent on the multifunctional Spo0A regulator controlling sporulation, biofilm formation and cannibalism. Barnase and binase also have some distinctions in practical applications. Barnase was initially suggested to be useful in research and biotechnology as a tool for studying protein–protein interactions, for RNA elimination from biological samples, for affinity purification of RNase fusion proteins, for the development of cloning vectors and for sterility acquisition by transgenic plants. Binase, as later barnase, was tested for antiviral, antitumour and immunogenic effects. Both RNases have found their own niche in cancer research as a result of success in targeted delivery and selectivity towards tumour cells.
Protein engineering to stabilize soluble amyloid β‐protein aggregates for structural and functional studies
Authors: Härd Torleif
Published: August 2011

The molecular biology underlying protein aggregation and neuronal death in Alzheimer’s disease is not yet completely understood, but small soluble nonamyloid aggregates of the amyloid β‐protein (Aβ) have been shown to play a fundamental neurotoxic role. The composition and biological action of such aggregates, known as oligomers and protofibrils, are therefore areas of intense study. However, research is complicated by the multitude of different interconverting aggregates that Aβ can form in vitro and in vivo, and by the inhomogeneity and instability of in vitro preparations. Here we review recent studies in which protein engineering, and in particular disulfide engineering, has been applied to stabilize different Aβ aggregates. For example, several techniques now exist to obtain stable and neurotoxic protofibrillar forms of Aβ, and engineered Aβ dimers, or larger aggregates formed by these, have been shown to specifically induce neuronal damage in a way that mimics Alzheimer’s disease pathology. Disulfide engineering has also revealed structural properties of neurotoxic aggregates, for instance that Aβ in protofibrils and globular oligomers adopts a β‐hairpin conformation that is similar to, but topologically distinct from, the conformation of Aβ in mature amyloid fibrils. Protein engineering is therefore a workable strategy to address many of the outstanding questions relating to the structure, interconversion and biological effects of oligomers and protofibrils of Aβ.
Statistical mechanics of 1D self-gravitating systems: the core—halo distribution
Authors: Teles T. N. , Levin Y. , Pakter R.
Published: August 2011

We study, using both theory and simulations, a system of self-gravitating sheets. A new statistical mechanics theory — free of any adjustable parameters is derived to quantitatively predict the final stationary state achieved by this system after the process of collisionless relaxation is completed. The theory shows a very good agreement with the numerical simulations. The model sheds new light on the general mechanism of relaxation of self-gravitating systems and may help us to understand cold matter distribution in the Universe.
Discovery of a spiral-host episodic radio galaxy
Authors: Hota Ananda , Sirothia S. K. , Ohyama Youichi , Konar C. , Kim Suk , Rey Soo-Chang , Saikia D. J. , Croston J. H. , Matsushita Satoki
Published: August 2011

We report the discovery of a unique radio galaxy at z= 0.137, which could possibly be the second spiral-host large radio galaxy and also the second triple—double episodic radio galaxy. The host galaxy shows signs of recent star formation in the ultraviolet but is optically red and is the brightest galaxy of a possible cluster. The outer relic radio lobes of this galaxy, separated by ∼1 Mpc, show evidence of spectral flattening and a high fraction of linear polarization. We interpret that these relic lobes have experienced re-acceleration of particles and compression of the magnetic field due to shocks in the cluster outskirts. From the morphology of the relics and galaxy distribution, we argue that re-acceleration is unlikely to be due to a cluster—cluster merger and speculate about the possibility of accretion shocks. The source was identified from Sloan Digital Sky Survey, Galaxy Evolution Explorer, NRAO VLA Sky Survey and Faint Images of the Radio Sky at Twenty-Centimetres survey data, but we also present follow-up optical observations with the Lulin telescope and 325-MHz low-frequency radio observations with the Giant Metrewave Radio Telescope. We briefly discuss the scientific potential of this example in understanding the evolution of galaxies and clusters by accretion, mergers, star formation and active galactic nucleus feedback.
Metabolic Stability of Peptidomimetics: N‐Methyl and Aza Heptapeptide Analogs of a PKB/Akt Inhibitor
Authors: Tal‐Gan Yftah , Freeman Noam S. , Klein Shoshana , Levitzki Alexander , Gilon Chaim
Published: August 2011

Linear peptides suffer from poor pharmacokinetic and pharmacodynamic properties. Peptidomimetics are designed to overcome these pharmacological drawbacks while maintaining the biological effects of the parent peptides. Aza‐peptides, in which an alpha carbon is replaced with nitrogen, are promising peptidomimetic analogs; however, little is known about the stability of these analogs toward enzymatic degradation. We performed systematic aza and N‐methyl scans of a PKB/Akt inhibitor, PTR6154. We evaluated the stability of the aza‐scan and N‐methyl scan libraries toward enzymatic degradation by trypsin/chymotrypsin. Our results indicate that the modification site is important for metabolic stability and that aza‐peptides have a more global effect than N‐methylation, affecting cleavage sites distant from the modification site.
Characterization of d‐boroAla as a Novel Broad‐Spectrum Antibacterial Agent Targeting d‐Ala‐d‐Ala Ligase
Authors: Putty Sandeep , Rai Aman , Jamindar Darshan , Pagano Paul , Quinn Cheryl L. , Mima Takehiko , Schweizer Herbert P. , Gutheil William G.
Published: August 2011

d‐boroAla was previously characterized as an inhibitor of bacterial alanine racemase and d‐Ala‐d‐Ala ligase enzymes (Biochemistry, 28, 1989, 3541). In this study, d‐boroAla was identified and characterized as an antibacterial agent. d‐boroAla has activity against both Gram‐positive and Gram‐negative organisms, with minimal inhibitory concentrations down to 8 μg / mL. A structure–function study on the alkyl side chain (NH2‐CHR‐B(OR’)2) revealed that d‐boroAla is the most effective agent in a series including boroGly, d‐boroHomoAla, and d‐boroVal. l‐boroAla was much less active, and N‐acetylation completely abolished activity. An LC‐MS / MS assay was used to demonstrate that d‐boroAla exerts its antibacterial activity by inhibition of d‐Ala‐d‐Ala ligase. d‐boroAla is bactericidal at 1× minimal inhibitory concentration against Staphylococcus aureus and Bacillus subtilis, which each encode one copy of d‐Ala‐d‐Ala ligase, and at 4× minimal inhibitory concentration against Escherichia coli and Salmonella enterica serovar Typhimurium, which each encode two copies of d‐Ala‐d‐Ala ligase. d‐boroAla demonstrated a frequency of resistance of 8 × 10−8 at 4× minimal inhibitory concentration in S. aureus. These results demonstrate that d‐boroAla has promising antibacterial activity and could serve as the lead agent in a new class of d‐Ala‐d‐Ala ligase targeted antibacterial agents. This study also demonstrates d‐boroAla as a possible probe for d‐Ala‐d‐Ala ligase function.
Opioid μ‐receptors in the rostral medullary raphe modulate hypoxia‐induced hyperpnea in unanesthetized rats
Authors: Dias M. B. , Nucci T. B. , Branco L. G. S. , Gargaglioni L. H.
Published: August 2011

Aim:  It has been suggested that the medullary raphe (MR) plays a key role in the physiological responses to hypoxia. As opioid μ‐receptors have been found in the MR, we studied the putative role of opioid μ‐receptors in the rostral MR (rMR) region on ventilation in normal and 7% hypoxic conditions.

Methods:  We measured pulmonary ventilation () and the body temperatures (Tb) of male Wistar rats before and after the selective opioid μ‐receptor antagonist CTAP (d‐Phe‐Cys‐Tyr‐d‐Trp‐Arg‐Thr‐Pen‐Thr‐NH2, cyclic, 0.1 μg per 0.1 μL) was microinjected into the rMR during normoxia or after 60 min of hypoxia.

Results:  The animals treated with intra‐rMR CTAP exhibited an attenuation of the ventilatory response to hypoxia (430 ± 86 mL kg−1 min−1) compared with the control group (790 ± 82 mL kg−1 min−1) (P < 0.05). No differences in the Tb were observed between groups during hypoxia.

Conclusion:  These data suggest that opioids acting on μ‐receptors in the rMR exert an excitatory modulation of hyperventilation induced by hypoxia.
Obesity augments the age‐induced increase in mitochondrial capacity for H2O2 release in Zucker fatty rats
Authors: Hey‐Mogensen M. , Jeppesen J. , Madsen K. , Kiens B. , Franch J.
Published: August 2011

Aim:  Mitochondrial dysfunction has been suggested to play a significant role in obesity and insulin resistance. The aim of the present study was to investigate if changes in obesity and insulin resistance were related to similar changes in mitochondrial capacity for hydrogenperoxide release in Zucker diabetic fatty rats and their lean littermates.

Methods:  Thirty‐four rats were used in this study. Rats were either lean or obese Zucker rats killed at 5–6 (young) or 12–14 (adults) weeks of age. Mitochondria were isolated from soleus muscles; respiration and release of hydrogenperoxide were determined and related to citrate synthase activity to determine intrinsic mitochondrial function. Mitochondrial‐specific super‐oxide dismuthase (MnSOD) protein content was determined in isolated mitochondria and muscle homogenate. Catalase protein content was determined in muscle homogenate.

Results:  Young lean and obese rats had a higher mitochondrial respiration when using palmitoyl‐l‐carnitine as substrate compared with adult lean and obese rats. The obese strain had higher mitochondrial hydrogenperoxide release but only in the adult animals. In both lean and obese animals, increased age was associated with increased mitochondrial hydrogenperoxide release. MnSOD tended to be higher in the obese strain in the isolated mitochondria. Regardless of age, catalase protein content was significantly lower in the obese rats.

Conclusions:  This study shows that the augmented increase in obesity and insulin resistance seen in Zucker diabetic fatty rats is associated with increased capacity for mitochondrial hydrogenperoxide release.
Real Options in flood risk management decision making
Authors: Woodward M. , Gouldby B. , Kapelan Z. , Khu S.‐T. , Townend I.
Published: August 2011

Effective flood risk management involves the quantification of flood risk and the implementation of cost‐effective, sustainable, and environmentally and socially acceptable measures that reduce flood risk. However, making decisions on the most appropriate long‐term intervention investments can be challenging; this is primarily because of the uncertainties associated with future climate change and socioeconomic development. Real Options analysis is a widely recognised approach for encouraging appropriate climate change adaptation and mitigation investment decisions. To date, however, there has only been limited use of Real Options Analysis Techniques within the Flood and Coastal Erosion Risk Management community. In this paper, a methodology is described that has the capability to assess the most appropriate set of interventions to make in a flood system, given the future uncertainties. The methodology captures the concepts of Real Options and has the capability to value the flexibility associated with potential flood risk management intervention options across a range of future climate change and socioeconomic scenarios. The novel Real Options approach has been tested and verified on a real‐life case study situated in the Thamesmead area of the Thames Estuary. The results obtained demonstrate the potential for substantial cost savings under future uncertainties when Real Options are used instead of more traditional, precautionary approaches.
A case of huge esophageal carcinosarcoma
Authors: Hu Mu , Zhi Xiu‐yi , Sun Ke‐lin
Published: August 2011

Carcinosarcoma of the esophagus is a rare malignant neoplasm with both epithelial and mesenchymal (sarcomatous) components. We describe a case of a 72‐year‐old man with a huge esophageal tumor which could often have been considered inoperable. However, the patient underwent a curative resection and had a good prognosis. In this report, we suggest that carcinosarcomas have a lower tendency of invasion, even late in their course. We therefore recommend aggressive surgical resection of this kind of tumor.
Evaluation of a point‐of‐care test for canine C‐reactive protein
Authors: Plickert Hanna D. , Einspanier Ralf , Arndt Gisela , Brunnberg Leo , Kohn Barbara
Published: August 2011

Background: In veterinary medicine, there is increasing interest in measuring C‐reactive protein (CRP) as a tool for diagnosis and monitoring of inflammatory diseases. Reported CRP concentrations for healthy dogs have ranged from 0 to 8.9 mg/L.

Objectives: The aims of this study were to evaluate a canine‐specific point‐of‐care (POC) lateral flow immunoassay for qualitative CRP measurement in healthy and diseased dogs and to compare results with those obtained by a quantitative ELISA.

Methods: Blood samples from 73 client‐owned dogs were available for testing: 16 healthy dogs and 57 dogs with a variety of infectious, inflammatory, or neoplastic diseases. CRP was measured in heparinized whole blood samples and serum with the TECOmedical Dog CRP‐visual POC test. A red line develops in the POC device if CRP is ≥5 mg/L, and results are scored as negative or positive. An ELISA validated previously for canine serum was used as the reference method.

Results: For all dogs, serum CRP concentrations measured by the ELISA ranged from 0.1 to ≥350 mg/L (median=38 mg/L). Percentages of the CRP POC test results that agreed with the ELISA results were 98.6% for whole blood and 97.3% for serum samples. For serum samples, sensitivity of the POC test was 96.4% and specificity was 81.3%. For whole blood, sensitivity was 94.7% and specificity was 93.8%.

Conclusions: The POC test had very good agreement with the ELISA test and had high sensitivity and specificity; therefore, it can be used as a qualitative test to screen for increases in CRP concentrations.
Neutrophilic myeloperoxidase index and mean light absorbance in neonatal septic and nonseptic foals
Authors: Piviani Martina , Segura Didac , Monreal Luis , Bach‐Raich Ester , Mesalles Montse , Pastor Josep
Published: August 2011

Background: Two neutrophilic indices reported by the ADVIA 120 Hematology Analyzer, neutrophilic myeloperoxidase index (MPXI), and mean light absorbance (neutrophil X mean [NXM]) have been proposed as indicators of systemic inflammatory disease in horses and of neutrophil activation in coronary ischemic syndromes in people.

Objective: The aim of this study was to evaluate NXM and MPXI in healthy, sick nonseptic, and sick septic foals to determine whether conditions likely associated with neutrophil activation result in decreases in these variables.

Methods: In this retrospective study, CBC data from 61 neonatal foals presented to the Equine Teaching Hospital of Barcelona were evaluated for correlations between MPXI, NXM, percentage of large unstained cells, neutrophil count, and percentage of band neutrophils. Results obtained in septic (n=32), sick nonseptic (n=22), and healthy foals (n=7) were compared. In addition, results recorded in septic/neutropenic (n=12), septic/non‐neutropenic (n=20), nonseptic/neutropenic (n=8), nonseptic/non‐neutropenic (n=14), and healthy foals (n=7) were also compared.

Results: A weak negative correlation was found between MPXI and neutrophil count and between NXM and percentage of band neutrophils. Septic/neutropenic foals had significantly higher MPXI values (median 17.9, minimum–maximum 4.7–42.5) than did septic/non‐neutropenic (1.5, −24.4 to 22.3), nonseptic/neutropenic (6.6, 0.6–17.9), and nonseptic/non‐neutropenic foals (8.8, −10.1 to 16.8) but did not differ significantly from controls (12.8, −8.5 to 20.4).

Conclusions: Significant differences in NXM or MPXI were not found when disease groups were compared with controls; however, septic/neutropenic foals had significantly higher median MPXI than other groups of sick foals. Further prospective studies are needed to clarify if this finding is related to decreased neutrophil function or activation in septic/neutropenic foals.
Age‐dependent remodelling of inhibitory synapses onto hippocampal CA1 oriens‐lacunosum moleculare interneurons
Authors: Salesse Charleen , Mueller Christopher Lacharité , Chamberland Simon , Topolnik Lisa
Published: August 2011

Non‐Technical Summary  The main function of the inhibitory synapse is to provide the membrane hyperpolarization and, thereby, to control the level of activity of its target cell. Extensively studied in pyramidal neurons, the properties of inhibitory synapses that target inhibitory interneurons remain largely unknown. We studied the properties of inhibitory synapses formed onto interneurons involved in the hippocampal feedback inhibitory circuit. Our data revealed a significant, age‐dependent strengthening of inhibition of interneurons due to the synaptic incorporation of the α5 subunit of the GABAA receptor. This novel mechanism of age‐dependent refinement of local circuit inhibition may have a direct impact on the hippocampal network activity and performance during development.
Modulation of the myogenic response in renal blood flow autoregulation by NO depends on endothelial nitric oxide synthase (eNOS), but not neuronal or inducible NOS
Authors: Dautzenberg Marcel , Keilhoff Gerburg , Just Armin
Published: August 2011

Non‐Technical Summary  Blood flow in the kidney is tightly regulated. This so‐called autoregulation is essential for the function of the kidney as well as for its protection against damage and failure from high blood pressure. Autoregulation is caused by three mechanisms. The signalling molecule nitric oxide (NO) modulates the balance of these mechanisms, blunting the contribution of the fastest mechanism and increasing that of the others. What is unknown is where in the kidney the responsible NO is originating. Our data indicate that the cells of the inner lining of the blood vessels are by far the most important source of NO for this effect compared to other NO‐producing cells in the relevant region of the kidney, such as macula densa, smooth muscle or mesangial cells. The findings are important for understanding blood flow autoregulation in the kidney as well as kidney function and failure.
Endothelin B receptor contribution to peripheral microvascular function in women with polycystic ovary syndrome
Authors: Wenner Megan M. , Taylor Hugh S. , Stachenfeld Nina S.
Published: August 2011

Non‐Technical Summary  Although the core feature in polycystic ovary syndrome (PCOS) is a hormonal imbalance, this syndrome is associated with obesity, insulin resistance, hypertension and endothelial dysfunction. This constellation of factors leads to greater risks for infertility, diabetes and cardiovascular disease. In this study we examine two important receptors involved in endothelial function, ET‐A and ET‐B, using the skin microcirculation to examine small blood vessel responses. We demonstrate that the ET‐B receptor is likely to play an important role in the pathophysiology of cardiovascular disease in women with PCOS.
Analysis of the Nonlinear Dynamics of the Timoshenko Flexible Beams Using Wavelets
Authors: Awrejcewicz J. , Krysko A. V. , Soldatov V. , Krysko V. A.
Published: August 2011

Regular and chaotic dynamics of the flexible Timoshenko-type beams is studied using both the standard Fourier (FFT) and the continuous wavelet transform methods. The governing equations of motion for geometrically nonlinear Timoshenko-type beams are reduced to a system of ODEs using both finite element method (FEM) and finite difference method (FDM) to ensure the reliability of numerical results. Scenarios of transition from regular to chaotic vibrations and beam dynamical stability loss are analyzed. Advantages and disadvantages of various wavelet functions are discussed. Application of continuous wavelet transform to the investigation of transitional and chaotic phenomena in nonlinear dynamics is illustrated and discussed.
Elastohydrodynamic Lubrication: A Gateway to Interfacial Mechanics—Review and Prospect
Authors: Zhu Dong , Jane Wang Q.
Published: August 2011

Elastohydrodynamic Lubrication (EHL) is commonly known as a mode of fluid-film lubrication in which the mechanism of hydrodynamic film formation is enhanced by surface elastic deformation and lubricant viscosity increase due to high pressure. It has been an active and challenging field of research since the 1950s. Significant breakthroughs achieved in the last 10–15 years are largely in the area of mixed EHL, in which surface asperity contact and hydrodynamic lubricant film coexist. Mixed EHL is of the utmost importance not only because most power-transmitting components operate in this regime, but also due to its theoretical universality that dry contact and full-film lubrication are in fact its special cases under extreme conditions. In principle, mixed EHL has included the basic physical elements for modeling contact, or hydrodynamic lubrication, or both together. The unified mixed lubrication models that have recently been developed are now capable of simulating the entire transition of interfacial status from full-film and mixed lubrication down to dry contact with an integrated mathematic formulation and numerical approach. This has indeed bridged the two branches of engineering science, contact mechanics, and hydrodynamic lubrication theory, which have been traditionally separate since the 1880s mainly due to the lack of powerful analytical and numerical tools. The recent advancement in mixed EHL begins to bring contact and lubrication together, and thus an evolving concept of “Interfacial Mechanics” can be proposed in order to describe interfacial phenomena more precisely and collaborate with research in other related fields, such as interfacial physics and chemistry, more closely. This review paper briefly presents snapshots of the history of EHL research, and also expresses the authors’ opinions about its further development as a gateway to interfacial mechanics.
Controlled formation of atomic step morphology on micropatterned Si (100)
Authors: Li K. , Pradeep N. , Chikkamaranahalli S. , Stan G. , Attota R. , Fu J. , Silver R.
Published: August 2011

Micrometer scale features are fabricated on Si (100) surfaces using lithographic techniques and thermally processed in an ultrahigh vacuum (UHV) environment. The process results in the formation of symmetric, step-terrace patterns with wide atomically flat regions exhibiting highly reproducible step-terrace morphology. The patterns spontaneously transform into a symmetric formation marked by step bunches separated by wide atomic terraces as a result of extended high temperature processing. A Monte Carlo model is introduced to understand the step flow and bunching process. The lithographic patterns remain visible post processing using a conventional optical microscope. The resulting patterns have the important property that they can be used as fiducial marks to externally locate nanoscale features fabricated on the large atomically flat terraces.
Size-dependent optical properties of Si nanocrystals embedded in amorphous SiO2 measured by spectroscopic ellipsometry
Authors: Wei J. , Price J. , Wang T. , Hessel C. , Downer M. C.
Published: August 2011

Silicon nanocrystals (Si NCs) with average diameters ⟨dNC⟩=3, 5 and 8 nm embedded in amorphous SiO2 synthesized by Si ion implantation have been characterized by spectroscopic ellipsometry. The dielectric function of the Si NCs has been extracted from SE data using a Bruggeman effective medium approximation and a Gauss–Lorentz oscillator model, taking into account the size dispersion of the nanoparticles. The dielectric function is found to depend strongly on average NC size. Although electronic critical point transitions of bulk silicon are discernible in NCs down to 3 nm diameter, the E1 resonance weakens with decreasing NC size, nearly disappearing for 3 nm diameter, while the dominant E2 transition blueshifts. In addition, a non-bulk-Si-like resonance intermediate between E1 and E2 is observed.
Correlation of Raman, electrical, and optical properties of high-κ, atomic layer deposited Al-doped TiO2
Authors: Haspert Lauren C. , Banerjee Parag , Henn-Lecordier Laurent , Rubloff Gary W.
Published: August 2011

Electrical characteristics of 25 nm Al-doped TiO2 (ATO) dielectric films are investigated in an effort to access the benefits of TiO2’s high dielectric constant (κ) while minimizing leakage current as needed for nanocapacitor applications. Al-doped films with 0-3.9 at. % Al were deposited using atomic layer deposition (ALD). As-deposited films of all compositions were amorphous and had poor electrical performance. Annealing at 600 °C was implemented to modify the film structure and to increase electrical performance. Raman spectroscopy monitored phase changes as a result of annealing. The Raman-measured Eg mode provides a clear signature of the anatase crystallization structure and showed the rapid formation of crystalline anatase in all films. The electrical performance of annealed films was significantly improved for films containing Al. Incorporation of few percent Al and annealing created a dramatic drop in leakage current from 10−3–10−4 to 10−7 A/cm2, nearly that of pure Al2O3. Comparing features of the Raman Eg mode with Al-doping displays a strong correlation to leakage currents. Trends observed in the Raman lineshape which relate to microstructural variances are discussed. Raman spectroscopy thus provides a measure of structural changes in ATO films which correlate strongly with its electrical characteristics as doping and annealing are employed to optimize the properties of the high-κ films.
Probing albumin adsorption onto calcium phosphates by x-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry
Authors: Baio J. E. , Weidner T. , Interlandi G. , Mendoza-Barrera C. , Canavan H. E. , Michel R. , Castner D. G.
Published: August 2011

In this study the binding and assembly of bovine serum albumin (BSA) onto three different calcium phosphate phases (hydroxyapatite, dibasic calcium phosphate dihydrate, and β-tricalcium phosphate) was investigated using a combination of x-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). XPS was used to record adsorption isotherms and to quantify the amount of BSA adsorbed onto the different CaP surfaces. On all three surfaces, a monolayer of adsorbed BSA was formed. ToF-SIMS was then used to investigate how the structure of BSA changes upon surface binding. ToF-SIMS data from BSA films on the three CaP surfaces showed intensity differences of secondary ions originating from both hydrophobic and hydrophilic amino acids. For a more quantitative examination of structural changes, the authors developed a ratio comparing the sum of intensities of secondary ions from hydrophobic and hydrophilic residues. A small, but statistically significant, increase in the value of this ratio (7%) was observed between a BSA film on hydroxyapatite versus dibasic calcium phosphate dihydrate. From this ratio, the authors can make some initial hypotheses about what specific changes in BSA structure relate to these differences observed in the ToF-SIMS data.
Polymer wires with quantum dots grown by molecular layer deposition of three source molecules for sensitized photovoltaics
Authors: Yoshimura Tetsuzo , Ebihara Ryosuke , Oshima Akio
Published: August 2011

Molecular layer deposition (MLD) can be used to grow organic tailored materials, where different molecules are sequentially connected in designated arrangements. Using MLD, polymer wires containing quantum dots (QDs) of lengths ∼0.8, ∼2, and ∼3 nm were grown by connecting three source molecules in monomolecular steps. The peak energy of the QD absorption shifted to higher energy with decreasing QD length, due to the quantum confinement effect. Consequently, the polymer wires exhibited a widening of their absorption spectra from ∼480 to ∼300 nm. This was attributed to the superposition of individual absorption bands of different QDs. A sensitization model for ZnO in photovoltaic devices is proposed, in which polymer wires with QDs as the sensitizing layer reduce the heat energy loss during absorption.
Evaluation of a 3D local multiresolution algorithm for the correction of partial volume effects in positron emission tomography
Authors: Le Pogam Adrien , Hatt Mathieu , Descourt Patrice , Boussion Nicolas , Tsoumpas Charalampos , Turkheimer Federico E. , Prunier‐Aesch Caroline , Baulieu Jean‐Louis , Guilloteau Denis , Visvikis Dimitris
Published: August 2011

Purpose:

Partial volume effects (PVEs) are consequences of the limited spatial resolution in emission tomography leading to underestimation of uptake in tissues of size similar to the point spread function (PSF) of the scanner as well as activity spillover between adjacent structures. Among PVE correction methodologies, a voxel‐wise mutual multiresolution analysis (MMA) was recently introduced. MMA is based on the extraction and transformation of high resolution details from an anatomical image (MR/CT) and their subsequent incorporation into a low‐resolution PET image using wavelet decompositions. Although this method allows creating PVE corrected images, it is based on a 2D global correlation model, which may introduce artifacts in regions where no significant correlation exists between anatomical and functional details.

Methods:

A new model was designed to overcome these two issues (2D only and global correlation) using a 3D wavelet decomposition process combined with a local analysis. The algorithm was evaluated on synthetic, simulated and patient images, and its performance was compared to the original approach as well as the geometric transfer matrix (GTM) method.

Results:

Quantitative performance was similar to the 2D global model and GTM in correlated cases. In cases where mismatches between anatomical and functional information were present, the new model outperformed the 2D global approach, avoiding artifacts and significantly improving quality of the corrected images and their quantitative accuracy.

Conclusions:

A new 3D local model was proposed for a voxel‐wise PVE correction based on the original mutual multiresolution analysis approach. Its evaluation demonstrated an improved and more robust qualitative and quantitative accuracy compared to the original MMA methodology, particularly in the absence of full correlation between anatomical and functional information.
Reliable automatic alignment of tomographic projection data by passive auto‐focus
Authors: Kingston A. , Sakellariou A. , Varslot T. , Myers G. , Sheppard A.
Published: August 2011

Purpose:

The authors present a robust algorithm that removes the blurring and double‐edge artifacts in high‐resolution computed tomography (CT) images that are caused by misaligned scanner components. This alleviates the time‐consuming process of physically aligning hardware, which is of particular benefit if components are moved or swapped frequently.

Methods:

The proposed method uses the experimental data itself for calibration. A parameterized model of the scanner geometry is constructed and the parameters are varied until the sharpest 3D reconstruction is found. The concept is similar to passive auto‐focus algorithms of digital optical instruments. The parameters are used to remap the projection data from thephysical detector to a virtual aligned detector. This is followed by a standard reconstruction algorithm, namely the Feldkamp algorithm. Feldkamp et al. [J. Opt. Soc. Am. A 1, 612–619 (1984)].

Results:

An example implementation is given for a rabbit liver specimen that was collected with a circular trajectory. The optimal parameters were determined in less computation time than that for a full reconstruction. The example serves to demonstrate that (a) sharpness is an appropriate measure for projection alignment, (b) our parameterization is sufficient to characterize misalignments for cone‐beam CT, and (c) the procedure determines parameter values with sufficient precision to remove the associated artifacts.

Conclusions:

The algorithm is fully tested and implemented for regular use at The Australian National University micro‐CT facility for both circular and helical trajectories. It can in principle be applied to more general imaging geometries and modalities. It is as robust as manual alignment but more precise since we have quantified the effect of misalignment.
A Polymorphism-Specific “Memory” Mechanism in the β
2
-Adrenergic Receptor
Authors: Ahles Andrea , Rochais Francesca , Frambach Torsten , Bünemann Moritz , Engelhardt Stefan
Published: August 2011

Variant forms of the β
2
-adrenergic receptor found in different individuals show distinct responses to repeated drug exposure.
β
2
-Adrenergic Receptor Polymorphisms and Signaling: Do Variants Influence the “Memory” of Receptor Activation?
Authors: Insel Paul A.
Published: August 2011

The functional importance of the response of β
2
AR polymorphic variants to repeated stimulation will need to be demonstrated.
Vampire Senses
Authors: Gough Nancy R.
Published: August 2011

An alternative splice variant in a TRPV channel allows vampire bats to detect the heat where blood flows in their prey.
A Roundabout Route to Secretion
Authors: Adler Elizabeth M.
Published: August 2011

Apically secreted Hedgehog is internalized and recycled for secretion at the basolateral membrane and establishment of the long-range morphogenetic gradient.
In Vitro
Activity of E1210, a Novel Antifungal, against Clinically Important Yeasts and Molds
Authors: Miyazaki Mamiko , Horii Takaaki , Hata Katsura , Watanabe Nao-aki , Nakamoto Kazutaka , Tanaka Keigo , Shirotori Syuji , Murai Norio , Inoue Satoshi , Matsukura Masayuki , Abe Shinya , Yoshimatsu Kentaro , Asada Makoto
Published: August 2011

E1210 is a new antifungal compound with a novel mechanism of action and broad spectrum of antifungal activity. We investigated the
in vitro
antifungal activities of E1210 compared to those of fluconazole, itraconazole, voriconazole, amphotericin B, and micafungin against clinical fungal isolates. E1210 showed potent activities against most
Candida
spp. (MIC
90
of ≤0.008 to 0.06 μg/ml), except for
Candida krusei
(MICs of 2 to >32 μg/ml). E1210 showed equally potent activities against fluconazole-resistant and fluconazole-susceptible
Candida
strains. E1210 also had potent activities against various filamentous fungi, including
Aspergillus fumigatus
(MIC
90
of 0.13 μg/ml). E1210 was also active against
Fusarium solani
and some black molds. Of note, E1210 showed the greatest activities against
Pseudallescheria boydii
(MICs of 0.03 to 0.13 μg/ml),
Scedosporium prolificans
(MIC of 0.03 μg/ml), and
Paecilomyces lilacinus
(MICs of 0.06 μg/ml) among the compounds tested. The antifungal action of E1210 was fungistatic, but E1210 showed no trailing growth of
Candida albicans
, which has often been observed with fluconazole. In a cytotoxicity assay using human HK-2 cells, E1210 showed toxicity as low as that of fluconazole. Based on these results, E1210 is likely to be a promising antifungal agent for the treatment of invasive fungal infections.
Phase III Randomized, Double-Blind Study Comparing Single-Dose Intravenous Peramivir with Oral Oseltamivir in Patients with Seasonal Influenza Virus Infection
Authors: Kohno Shigeru , Yen Muh-Yong , Cheong Hee-Jin , Hirotsu Nobuo , Ishida Tadashi , Kadota Jun-ichi , Mizuguchi Masashi , Kida Hiroshi , Shimada Jingoro
Published: August 2011

Antiviral medications with activity against influenza viruses are important in controlling influenza. We compared intravenous peramivir, a potent neuraminidase inhibitor, with oseltamivir in patients with seasonal influenza virus infection. In a multinational, multicenter, double-blind, double-dummy randomized controlled study, patients aged ≥20 years with influenza A or B virus infection were randomly assigned to receive either a single intravenous infusion of peramivir (300 or 600 mg) or oral administration of oseltamivir (75 mg twice a day [b.i.d.] for 5 days). To demonstrate the noninferiority of peramivir in reducing the time to alleviation of influenza symptoms with hazard model analysis and a noninferiority margin of 0.170, we planned to recruit 1,050 patients in South Korea, Japan, and Taiwan. A total of 1,091 patients (364 receiving 300 mg and 362 receiving 600 mg of peramivir; 365 receiving oseltamivir) were included in the intent-to-treat infected population. The median durations of influenza symptoms were 78.0, 81.0, and 81.8 h in the groups treated with 300 mg of peramivir, 600 mg of peramivir, and oseltamivir, respectively. The hazard ratios of the 300- and 600-mg-peramivir groups compared to the oseltamivir group were 0.946 (97.5% confidence interval [CI], 0.793, 1.129) and 0.970 (97.5% CI, 0.814, 1.157), respectively. Both peramivir groups were noninferior to the oseltamivir group (97.5% CI, <1.170). The overall incidence of adverse drug reactions was significantly lower in the 300-mg-peramivir group, but the incidence of severe reactions in either peramivir group was not different from that in the oseltamivir group. Thus, a single intravenous dose of peramivir may be an alternative to a 5-day oral dose of oseltamivir for patients with seasonal influenza virus infection.
Once-Daily Amikacin Dosing in Burn Patients Treated with Continuous Venovenous Hemofiltration
Authors: Akers Kevin S. , Cota Jason M. , Frei Christopher R. , Chung Kevin K. , Mende Katrin , Murray Clinton K.
Published: August 2011

Amikacin clearance can be increased in burn injury, which is often complicated by renal insufficiency. Little is known about the impact of renal replacement therapies, such as continuous venovenous hemofiltration (CVVH), on amikacin pharmacokinetics. We retrospectively examined the clinical pharmacokinetics, bacteriology, and clinical outcomes of 60 burn patients given 15 mg/kg of body weight of amikacin in single daily doses. Twelve were treated with concurrent CVVH therapy, and 48 were not. The pharmacodynamic target of ≥10 for the maximum concentration of drug in serum divided by the MIC (
C
max
/MIC) was achieved in only 8.5% of patients, with a small reduction of
C
max
in patients receiving CVVH and no difference in amikacin clearance. Mortality and burn size were greater in patients who received CVVH. Overall, 172 Gram-negative isolates were recovered from the blood cultures of 39 patients, with amikacin MIC data available for 82 isolates from 24 patients. A 10,000-patient Monte Carlo simulation was conducted incorporating pharmacokinetic and MIC data from these patients. The cumulative fraction of response (CFR) was similar in CVVH and non-CVVH patients. The CFR rates were not significantly improved by a theoretical 20 mg/kg amikacin dose. Overall, CVVH did not appear to have a major impact on amikacin serum concentrations. The low pharmacodynamic target attainment appears to be primarily due to higher amikacin MICs rather than more rapid clearance of amikacin related to CVVH therapy.
Impairment of Swimming Motility by Antidiarrheic Lactobacillus acidophilus Strain LB Retards Internalization of Salmonella enterica Serovar Typhimurium within Human Enterocyte-Like Cells
Authors: Liévin-Le Moal Vanessa , Amsellem Raymonde , Servin Alain L.
Published: August 2011

We report that both culture and the cell-free culture supernatant (CFCS) of
Lactobacillus acidophilus
strain LB (Lactéol Boucard) have the ability (i) to delay the appearance of
Salmonella enterica
serovar Typhimurium strain SL1344-induced mobilization of F-actin and, subsequently, (ii) to retard cell entry by
S
. Typhimurium SL1344. Time-lapse imaging and Western immunoblotting showed that
S
. Typhimurium SL1344 swimming motility, as represented by cell tracks of various types, was rapidly but temporarily blocked without affecting the expression of FliC flagellar propeller protein. We show that the product(s) secreted by
L. acidophilus
LB that supports the inhibitory activity is heat stable and of low molecular weight. The product(s) caused rapid depolarization of the
S
. Typhimurium SL1344 cytoplasmic membrane without affecting bacterial viability. We identified inhibition of swimming motility as a newly discovered mechanism by which the secreted product(s) of
L. acidophilus
strain LB retards the internalization of the diarrhea-associated pathogen
S. enterica
serovar Typhimurium within cultured human enterocyte-like cells.