bluuebunny/crossref_metadata_2025 huggingface dataset:
PTP1B deficiency enhances liver growth during suckling by increasing the expression of insulin‐like growth factor‐I
Authors: Escrivá Fernando , González‐Rodriguez Águeda , Fernández‐Millán Elisa , Rondinone Cristina M. , Álvarez Carmen , Valverde Ángela M.
Published: May 2010

Protein tyrosine phosphatase 1B (PTP1B) is a negative regulator of insulin and tyrosine kinase growth factor signaling. We have recently demonstrated that PTP1B deficiency increases GLUT2/insulin receptor (IR) A complexes and glucose uptake in suckling, but not adult, primary hepatocytes. Herein we have investigated intrahepatic glucose utilization in 3–5 days old wild‐type and PTP1B−/− mice. PTP1B deficiency decreased glycogen, lactate, and pyruvate content in the livers from suckling mice. Conversely, the activity of glucose 6‐phosphate dehydrogenase (G6PD), the rate limiting enzyme of the pentose phosphate cycle (PPC) which provides substrates for DNA synthesis, was enhanced in the liver of PTP1B−/− animals. Liver weight, liver‐to‐body mass ratio, DNA content, and PCNA expression were increased in PTP1B−/− suckling mice compared to the wild‐type controls. At the molecular level, STAT 5B phosphorylation, IGF‐I mRNA, and protein levels as well as IGF‐IR tyrosine phosphorylation were increased in the livers of PTP1B‐deficient neonates. Unexpectedly, hepatic and serum triglycerides (TG) were increased by PTP1B deficiency, although the expression of lipogenic enzymes remained as in the wild‐type controls. However, the analysis of milk composition revealed higher TG content in lactating females lacking PTP1B. The effects of PTP1B deficiency on G6PD activity, STAT 5B/IGF‐I/IGF‐IR axis, PCNA expression and liver growth during suckling were maintained by transferring PTP1B−/− embryos (PTP1B−/−T) to a wild‐type female. Conversely, PTP1B−/−T mice did not show hepatic fat accumulation. In conclusion, the present study suggests that PTP1B plays a unique role in the control of the physiological liver development after birth. J. Cell. Physiol. 225: 214–222, 2010. © 2010 Wiley‐Liss, Inc.
Syzygium cumini leaf and seed extract mediated biosynthesis of silver nanoparticles and their characterization
Authors: Kumar Vineet , Yadav Subhash C , Yadav Sudesh Kumar
Published: May 2010

BACKGROUND: Plant mediated synthesis of metallic nanoparticles has been studied and reported, however, to date, the biomolecules involved in the synthesis of metallic nanoparticles have not been characterized. This study was therefore undertaken to characterize the biomolecules of Syzygium cumini involved in the synthesis of silver nanoparticles.

RESULTS: Synthesis kinetics and morphological characterization of silver nanoparticles (SNP) synthesized using leaf extract (LE) and seed extract (SE) as well as their polar (water) fractions from Syzygium cumini were compared. The polyphenols content and high performance liquid chromatography (HPLC) profile of different fractions revealed good correlation between size and synthesis rate of SNP. SE contains more polyphenols and biochemical constituents than LE and therefore, showed higher synthesis rate and bigger sized SNP. To analyse the nature of biomolecules involved in the synthesis of SNP, LE and SE were fractionated on a polarity basis by solvent–solvent partitioning. Only the water fractions of LE and SE showed potential for SNP synthesis. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis of SNP indicated that all fractions catalyze the synthesis of spherical nanoparticles. The average size of SNP synthesized by LE, leaf water fraction, SE and seed water fraction were 30, 29, 92, and 73 nm respectively.

CONCLUSION: Results suggest that only highly polar soluble constituents are responsible for SNP synthesis. The size of SNP was found to be directly correlated with the amount of polyphenols as well as surfactants present in the reaction solution. Thus, the amount of polyphenols could be one of the crucial parameters determining the size and distribution of SNP. Copyright © 2010 Society of Chemical Industry
Iodide mumps: Sonographic appearance
Authors: Greco S. , Centenaro R. , Lavecchia G. , Rossi F.
Published: May 2010

Swelling of the salivary glands occurring after injection of iodine‐based contrast agent is a rare late adverse reaction. Only a few cases in the literature illustrate such ultrasound findings. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:438–439, 2010
“But we can't go back”
Authors: Spiers Judith A. , Cummings Greta G. , Langenhoff Paula , Sharlow Janice , Bhatti Aslam
Published: May 2010

In 2004, a provincial cancer agency in Canada developed and implemented a provincewide Leadership Development Initiative (LDI) to enhance organizational leadership and relationships. Research using a quasi‐experimental survey design determined whether LDI implementation influenced the emotional health and leadership practices of LDI participants. An ethnographic approach (18 focus groups and 13 individual interviews) explored participants' perceptions of the LDI. This article presents qualitative findings that contribute to understanding the statistically significant findings of increasing levels of cynicism, emotional exhaustion, and burnout for most LDI participants. The LDI was regarded as a critical strategy for helping leaders grow and cope with change and help in changing organizational leadership culture to be more collaborative and inclusive. However, an organizational history of short‐lived, flavor‐of‐the‐month development initiatives and growing skepticism and disengagement by leaders represented in the themes of Catch‐22 and “there is no going back” contributes to understanding why these quantitative measures increased. Few studies have explored the hypothesis that real organizational development happens through a series of planned stages. In this study, leaders experienced escalating frustration because change was not seen to occur fast enough in “others” and reported that this was necessary before they would alter their own behavior. Leadership development programs in general need to reflect the reality that it takes considerable time, patience, and effort to effect fundamental change in leadership culture.
Enabling or “real” power and influence in leadership
Authors: Drew Glenys M.
Published: May 2010

On the theme of personal development, this conceptual article aims to provoke thought about power and influence in leadership by means of a short excursion into character depictions in J.R.R. Tolkien's The Lord of the Rings (1966). It is said of mythopoeic literature, the genre of Tolkien's work, that the very simplicity of the lens “pares away distractions,” “opens the way to unexpected connections, … [and] draws attention to alternative modes of being and thinking” (Greene, 1994, p. 457). Taking the liberty of perceived applicability of Tolkien's literary genius to motifs on leadership, this article provokes thinking on what constitutes “real” power and influence in leadership. It is contended that demonstrating real power and influence in leadership lies not in coercive tactics of wielding power over others but in withholding usurping power to work with and enable others to achieve worthwhile ends. Three suggested markers of enabling or real power and influence in leadership are explored. Each one contains an element of paradox. The proposed markers suggest, in turn, that enabling or real power and influence does not usurp but serves, that it sublimates self‐interest for the interests of others and the intended goal, and that it positions for growth for the self and others and fosters true engagement in leadership. The article offers some empirical evidence as to the efficacy of the proposed markers for effective leadership and suggests a further research strategy to test the proposed markers empirically.
Higher education in the global knowledge economy
Authors: Molina‐Ray Caroline
Published: May 2010

Technology and globalization have the potential to make higher education more affordable and accessible. In practice, however, rising costs limit educational access, and competition threatens the sustainability of many colleges and universities (Grummon, 2009). With the relevance of traditional curricula in question and the demand for alternate delivery methods expanding, many higher learning institutions face a challenge to reinvent themselves (Barnatt, 2008; Grummon, 2009; Lee, Brennan, & Green, 2009).

We asked four higher education leaders from demographically and structurally diverse institutions to address the question, “How will colleges and universities serve the global knowledge economy in the coming decades?” Our respondents represent perspectives from multiple educational paradigms—public and private, local and international, for‐profit and nonprofit, brick‐and‐mortar and online.

George Mihel, president of Sauk Valley Community College in Illinois, offers a position paper on the need to transform some of higher education’s deep‐rooted institutional traditions. George Miller, chancellor of American InterContinental University, teams with Caroline Molina‐Ray, a University of Phoenix faculty member, to address how higher education can foster both technological competency and critically reflexive thinking. Naana J. S. Opoku‐Agyemang, vice chancellor of the University of Cape Coast in Ghana, offers insight into the unique challenges and accomplishments of higher education in Africa. Finally, Vicki T. Purslow, associate dean of the College of Arts and Sciences at Southern Oregon University, and Christine Cook Florence, a higher education marketing consultant, present a commentary synthesizing the symposium contributions and issuing a call to action for higher education leaders. Together, these diverse perspectives offer a glimpse into the higher education of the future.
Resolving the Holocene alluvial record in southeastern Australia using luminescence and radiocarbon techniques
Authors: Cheetham Michael D. , Keene Annabelle F. , Erskine Wayne D. , Bush Richard T. , Fitzsimmons Kathryn , Jacobsen Geraldine E. , Fallon Stewart J.
Published: May 2010

A previous assessment of radiocarbon (14C) dates from alluvial units in southeastern Australia revealed a gap in the geochronological record that coincides with the Holocene climatic optimum. This gap in the alluvial record can be further refined using optically stimulated luminescence (OSL). The chronology of Holocene river terraces on Widden Brook, a sandy alluvial stream in southeastern Australia, was established using14C and OSL techniques. Combined use of these independent techniques allows for a more rigorous assessment of the alluvial record. The robust chronology, consisting of 3814C and 11 OSL samples, permitted identification of significant depositional variation within the catchment, resulting from localised geomorphic processes. The three terrace sequences identified yielded distinct chronologies, suggesting alluvial deposition at different times. The sequences exhibited a continuous chronology, which indicated continuous deposition throughout the Holocene. The chronology of terrace sequences within this catchment suggests that terrace formation can be attributed to localised geomorphic processes rather than climatic forcing. Copyright © 2010 John Wiley & Sons, Ltd.
Single‐molecule surface‐enhanced Raman scattering of fullerene C60
Authors: Luo Zhixun , Loo Boon H. , Peng Aidong , Ma Ying , Fu Hongbing , Yao Jiannian
Published: May 2010

We achieved single‐molecule surface‐enhanced Raman scattering (SM‐SERS) spectra from ultralow concentrations (10−15 M) of fullerene C60 on uniformly assembled Au nanoparticles. It was found that resonant excitation at 785 nm is a powerful tool to probe SM‐SERS in this system. The appearance of additional bands and splitting of some vibrational modes were observed because of the symmetry reduction of the adsorbed molecule and a relaxation in the surface selection rules. Time‐evolved spectral fluctuation and ‘hot spot’ dependence in the SM‐SERS spectra were demonstrated to result from the single‐molecule Raman behavior of the spherical C60 on Au nanoparticles. Copyright © 2010 John Wiley & Sons, Ltd.
Aspirin and compression devices versus low‐molecular‐weight heparin and PCD for VTE prophylaxis in orthopedic oncology patients
Authors: Patel Anay R. , Crist Martha K. , Nemitz Jason , Mayerson Joel L.
Published: May 2010

Background

Deep venous thrombosis (DVT) and pulmonary embolism (PE) are possible sources of morbidity and mortality in patients with musculoskeletal neoplasms (MSN).

Objective

To compare the efficacy of aspirin (ASA) and pneumatic compression devices (PCD) to low‐molecular‐weight heparin (LMWH) and PCD in patients undergoing orthopedic procedures for MSN of the pelvis or lower extremity.

Methods

Of 348 patients who met the study criteria, 195 were treated with ASA/PCD and 153 with LMWH/PCD. There were 18 DVT including 8 in ASA/PCD group and 10 in LMWH/PCD group. There were four PEs, all in the LMWH/PCD group.

Results

We found no significant difference in DVT rate between ASA/PCD and LMWH/PCD when used for prophylaxis against thromboembolic complications. Our analysis shows that procedures of the thigh, soft tissue resections, and malignant disease were more often managed with ASA/PCD while joint arthroplasty, procedures of the hip/pelvis, and metastatic disease were more often managed with LMWH/PCD.

Conclusion

DVT prophylaxis in orthopedic oncology remains a complex topic in which physicians must balance the risks of thromboembolic disease against the risks of post‐operative complications. J. Surg. Oncol. 2010;102:276–281. © 2010 Wiley‐Liss, Inc.
Monitoring land use change in the Çeşme coastal zone, Turkey using aerial photographs and satellite imaging
Authors: Hepcan Ç. C. , Turan İ. A. , Özkan M. B.
Published: May 2010

Humans change the landscapes and especially the coastal zones for their requirements. The aim of the study was to analyse land use changes in the Çeşme coastal zone, Turkey, during a 48‐year period (1957–2005) using remote sensing and GIS. In this study, land use changes in the Çeşme coastal zone were analysed using the four sets of land use maps derived from aerial photographs and classified satellite image taken in the years 1957, 1976, 1995 and 2005. Post‐classification algorithm change detection was applied to observe land use changes during three time periods: Period 1 (1957–1976), Period 2 (1976–1995) and Period 3 (1995–2005). The results showed that natural land cover and agricultural lands decreased and built‐up area increased throughout the study area during the 48‐year period between 1957 and 2005. Furthermore, land use change was successively increased in Period 1, Period 3 and Period 2. Copyright © 2010 John Wiley & Sons, Ltd.
Successful outcomes following living donor liver transplantation for portopulmonary hypertension
Authors: Bandara Mahesh , Gordon Fredric D. , Sarwar Akmal , Knauft Elizabeth M. , Pomfret Elizabeth A. , Freeman Richard B. , Wirth Joel A.
Published: May 2010

Pulmonary arterial hypertension (PAH) associated with portal hypertension [portopulmonary hypertension (PPHTN)] occurs in 2% to 10% of patients with advanced liver disease and carries a very poor prognosis without treatment. Most hepatic transplantation centers consider moderate to severe PPHTN to be a contraindication to liver transplantation because of the high rate of perioperative complications. We present 3 patients with PPHTN who were managed with intravenous prostacyclin therapy followed by living donor liver transplantation (LDLT). These individuals demonstrated subsequent resolution of their pulmonary hypertension and were weaned off all PAH-specific medical therapy. We present their demographics, clinical courses, and hemodynamics. We discuss the potential indications for LDLT and risks with respect to this patient population. Limitations of the Model for End-Stage Liver Disease scoring system and outcome data for this patient population are reviewed. Future studies should be directed toward better defining indications for LDLT in patients with PPHTN, improving medicosurgical management, and assessing long-term outcomes. Liver Transpl 16:983-989, 2010. © 2010 AASLD.
A Galois correspondence for countable short recursively saturated models of PA
Authors: Shochat Erez
Published: May 2010

In this paper we investigate the properties of automorphism groups of countable short recursively saturated models of arithmetic. In particular, we show that Kaye's Theorem concerning the closed normal subgroups of automorphism groups of countable recursively saturated models of arithmetic applies to automorphism groups of countable short recursively saturated models as well. That is, the closed normal subgroups of the automorphism group of a countable short recursively saturated model of PA are exactly the stabilizers of the invariant cuts of the model which are closed under exponentiation. This Galois correspondence is used to show that there are countable short recursively saturated models of arithmetic whose automorphism groups are not isomorphic as topological groups. Moreover, we show that the automorphism groups of countable short arithmetically saturated models of PA are not topologically isomorphic to the automorphism groups of countable short recursively saturated models of PA which are not short arithmetically saturated (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A note on stability spectrum of generic structures
Authors: Anbo Yuki , Ikeda Koichiro
Published: May 2010

We show that if a class K of finite relational structures is closed under quasi‐substructures, then there is no saturated K‐generic structure that is superstable but not ω ‐stable (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Some observations on the substructure lattice of a Δ1 ultrapower
Authors: McLaughlin Thomas G.
Published: May 2010

Given a (nontrivial) Δ1 ultrapower ℱ/𝒰, let ℒ︁U denote the set of all Π2‐correct substructures of ℱ/𝒰; i.e., ℒ︁U is the collection of all those subsets of |ℱ/𝒰| that are closed under computable (in the sense of ℱ/𝒰) functions. Defining in the obvious way the lattice ℒ︁(ℱ/𝒰)) with domain ℒ︁U, we obtain some preliminary results about lattice embeddings into – or realization as – an ℒ︁(ℱ/𝒰). The basis for these results, as far as we take the matter, consists of (1) the well‐known class of (non‐trivial) minimal ℱ/𝒰's, which function as atoms, and (2) the class of minimalfree ℱ/𝒰's, to whose nonemptiness a substantial section of the paper is devoted. It is shown that an infinite, convergent monotone sequence together with its limit point is embeddable in an ℒ︁(ℱ/𝒰), and that the initial segment lattices {0, 1,…, n } are not just embeddable in (as is trivial), but in fact realizable as, lattices ℒ︁(ℱ/𝒰). Finally, the diamond is (easily) embeddable; and if it is not realizable, then either the 1 ‐ 3 ‐ 1 lattice or the pentagon is at least embeddable (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Boolean products of R0‐algebras
Authors: Zhou Xiangnan , Li Qingguo
Published: May 2010

In this paper, the (weak) Boolean representation of R0‐algebras are investigated. In particular, we show that directly indecomposable R0‐algebras are equivalent to local R0‐algebras and any nontrivial R0‐algebra is representable as a weak Boolean product of local R0‐algebras (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Existentially closed ordered difference fields and rings
Authors: Point Françoise
Published: May 2010

We describe classes of existentially closed ordered difference fields and rings. We show an Ax‐Kochen type result for a class of valued ordered difference fields (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Abelian groups and quadratic residues in weak arithmetic
Authors: Jeřábek Emil
Published: May 2010

We investigate the provability of some properties of abelian groups and quadratic residues in variants of bounded arithmetic. Specifically, we show that the structure theorem for finite abelian groups is provable in S22 + iWPHP(Σ1b), and use it to derive Fermat's little theorem and Euler's criterion for the Legendre symbol in S22 + iWPHP(PV) extended by the pigeonhole principle PHP(PV). We prove the quadratic reciprocity theorem (including the supplementary laws) in the arithmetic theories T20 + Count2(PV) and I Δ0 + Count2(Δ0) with modulo‐2 counting principles (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Zariski‐type topology for implication algebras
Authors: Abad Manuel , Castaño Diego , Díaz Varela José P.
Published: May 2010

In this work we provide a new topological representation for implication algebras in such a way that its one‐point compactification is the topological space given in [1]. Some applications are given thereof (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Lévy processes on a first order model
Authors: Ng Siu‐Ah
Published: May 2010

The classical notion of Lévy process is generalized to one that takes as its values probabilities on a first or‐der model equipped with a commutative semigroup. This is achieved by applying a convolution product on definable probabilities and the infinite divisibility with respect to it (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A discrete representation of free MV‐algebras
Authors: Di Nola Antonio , Grigolia Revaz , Spada Luca
Published: May 2010

We prove that the m ‐generated free MV‐algebra is isomorphic to a quotient of the disjoint union of all the m ‐generated free MV(n)‐algebras. Such a quotient can be seen as the direct limit of a system consisting of all free MV(n)‐algebras and special maps between them as morphisms (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Novel Approach for the Desalination of Seawater by Means of Reusable Poly(acrylic acid) Hydrogels and Mechanical Force
Authors: Höpfner Johannes , Klein Christopher , Wilhelm Manfred
Published: May 2010

Desalination of a sodium chloride solution is achieved by the incorporation of salt depleted water into an acrylic acid based hydrogel and the subsequent deswelling of the gel by mechanical force to gain water with a lower salt content. This is a new approach towards the problem of desalination of seawater that has, to the best of our knowledge, not been presented before. In a proof‐of‐principle experiment the salt content of a 10 g/L NaCl solution could be reduced by 35% in one cycle. The influence of main chemical parameters, e.g. degree of crosslinking, degree of neutralization and experimental parameters like particle size and salt concentration on the desalination process are examined. Possible optimum conditions for the desalination using a poly(acrylic acid) network are discussed and the construction of a simple apparatus for deswelling by mechanical force is described.

magnified image
Betulin induces mitochondrial cytochrome c release associated apoptosis in human cancer cells
Authors: Li Yang , He Kan , Huang Yinghui , Zheng Daxin , Gao Chang , Cui Lin , Jin Ying‐Hua
Published: May 2010

We examined whether betulin, a naturally abundant compound, has anticancer functions in human cancer cells. The results showed that betulin significantly inhibited cell viability in cervix carcinoma HeLa cells, hepatoma HepG2 cells, lung adenocarcinoma A549 cells, and breast cancer MCF‐7 cells with IC50 values ranging from 10 to 15 µg/mL. While betulin exhibited only moderate anticancer activity in other human cancer cells such as hepatoma SK‐HEP‐1 cells, prostate carcinoma PC‐3, and lung carcinoma NCI‐H460, with IC50 values ranging from 20 to 60 µg/mL, it showed minor growth inhibition in human erythroleukemia K562 cells (IC50 > 100 µg/mL). We further investigated the mechanism of anticancer activity by betulin, using HeLa cells as an experimental model. Betulin (10 µg/mL) induces apoptotic cell death, as evidenced by morphological characteristics such as membrane phosphatidylserine translocation, nuclear condensation/fragmentation, and apoptotic body formation. A kinetics analysis showed that the depolarization of mitochondrial membrane potential and the release of mitochondrial cytochrome c occurred as early as 30 min after treatment with betulin. Betulin, unlike its chemical derivative betulinic acid, did not directly trigger mitochondrial cytochrome c release in isolated mitochondria. Importantly, Bax and Bak were rapidly translocated to the mitochondria 30 min after betulin treatment. The sequential activation of caspase‐9 and caspase‐3/‐7 and the cleavage of poly(ADP‐ribose) polymerase (PARP) were observed behind those mitochondrial events. Furthermore, specific downregulation of either caspase‐9, Bax, or Bak by siRNA effectively reduced PARP cleavage and caspase‐3 activation. Taken together, the lines of evidence demonstrate that betulin triggers apoptosis of human cancer cells through the intrinsic apoptotic pathway. © 2010 Wiley‐Liss, Inc.
Adipokine regulation of colon cancer: Adiponectin attenuates interleukin‐6‐induced colon carcinoma cell proliferation via STAT‐3
Authors: Fenton Jenifer I. , Birmingham Janette M.
Published: May 2010

Obesity results in increased circulating levels of specific adipokines, which are associated with colon cancer risk. The disease state is associated with increased leptin, insulin, IGF‐1, and IL‐6. Conversely, adiponectin levels are decreased in obese individuals. Previously, we demonstrated adipokine‐enhanced cell proliferation in preneoplastic, but not normal, colon epithelial cells, demonstrating a differential effect of adipokines on colon cancer progression in vitro. Using a model of late stage carcinoma cancer cell, namely murine MC‐38 colon carcinoma cells, we compared the effect of obesity‐associated adipokines (leptin, insulin, IGF‐1, and IL‐6) on MC‐38 cell proliferation and determined whether adiponectin (full length or globular) could modulate adipokine‐induced cell proliferation. We show that insulin and IL‐6, but not leptin and IGF‐1, induce proliferation in MC‐38 cells. Adiponectin treatment of MC‐38 cells did not inhibit insulin‐induced cell proliferation but did inhibit IL‐6‐induced cell proliferation by decreasing STAT‐3 phosphorylation and activation. Nitric oxide (NO) production was increased in MC‐38 cells treated with IL‐6; co‐treatment with adiponectin blocked IL‐6‐induced iNOS and subsequent NO production. These data are compared to previously reported findings from our laboratory using the YAMC (model normal colon epithelial cells) and IMCE (model preneoplastic) cells. The cell lines are utilized to construct a model summarizing the hormonal consequences of obesity and the impact on the differential regulation of colon epithelial cells along the continuum to carcinoma. These data, taken together, highlight mechanisms involved in obesity‐associated cancers and may lead to potential‐targeted therapies. © 2010 Wiley‐Liss, Inc.
Modelling a slow smoldering combustion process
Authors: Fasano A. , Mimura M. , Primicerio M.
Published: May 2010

We present a mathematical model for the slow and partial combustion process of a sheet of paper ignited on one side and in the presence of a flow of air confined in a narrow gap above the paper. The model includes mass and thermal balance for the various components. After having introduced some simplifications, a suitable rescaling is performed and some limit cases are examined. Two classes of travelling wave solutions are analyzed, corresponding to the opposite cases of a sufficiently large or of a moderate air flow. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of nanotalc inclusion on mechanical, microstructural, melt shear rheological, and crystallization behavior of polyamide 6‐based binary and ternary nanocomposites
Authors: Balamurugan G. Prasath , Maiti S.N.
Published: May 2010

The objective of the study is to investigate the effect of inclusion of nanotalc on the strength properties of polyamide 6 (PA6)‐based binary and ternary nanocomposites. Binary nanocomposites were prepared by melt compounding of PA6 with varying content of nanotalc (1, 2, and 4 wt%). Ternary nanocomposites were prepared by melt compounding of compatibilized blend of PA 6 and ethylene‐co‐butyl acrylate (EBA elastomer) with varying content of nanotalc (1, 2, and 4 wt%). Both the binary and ternary nanocomposites registered a very high improvement in the strength/stiffness‐related properties at lower filler loading of 1 wt%. Phase morphology of the composites studied by SEM, TEM, and XRD revealed the formation of extended brane‐like structures and delaminated talc layers in the binary nanocomposites. The modulus predicted by Halpin‐Tsai and Mooney equation suggests that the composites retained a very good aspect ratio after melt mixing. Orientation effects of nanotalc enhanced the melt flow behavior in the composites. POLYM. ENG. SCI., 50:1978–1993, 2010. © 2010 Society of Plastics Engineers
Nanoclay‐reinforced, polypropylene‐based wood–plastic composites
Authors: Yeh Shu‐Kai , Gupta Rakesh K.
Published: May 2010

Wood plastic composites (WPCs) are a new class of materials which combine the characteristics of plastic and wood. In appearance, they are similar to wood, but the low stiffness of plastics makes the composite modulus significantly lower than that of solid wood. Increasing the wood content in the WPCs can improve stiffness, but the rate of water absorption also goes up. Here, nanoclay was compounded with wood and plastic using a twin screw extruder to form a three‐component composite to improve the stiffness of WPCs. To overcome the previously observed reduction in strength and increase in the rate of water absorption, different compounding procedures were used. It was found that pre‐compounding wood flour with polymer followed by incorporation of clay in a second step resulted in an increase in stiffness, retention in strength, and a reduction in the rate of water absorption. Thus, adding nanoclays is an alternative for increasing properties instead of adding extra wood flour to a concentration in excess of 55 wt% as this involves processing difficulties. POLYM. ENG. SCI., 50:2013–2020, 2010. © 2010 Society of Plastics Engineers
Study of monocyte membrane proteome perturbation during lipopolysaccharide‐induced tolerance using iTRAQ‐based quantitative proteomic approach
Authors: Zhang Huoming , Zhao Changqing , Li Xin , Zhu Yi , Gan Chee Sian , Wang Yong , Ravasi Timothy , Qian Pei‐Yuan , Wong Siew Cheng , Sze Siu Kwan
Published: May 2010

Human monocytes' exposure to low‐level lipopolysaccharide (LPS) induces temporary monocytic insensitivity to subsequent LPS challenge. The underlying mechanism of this phenomenon could have important clinical utilities in preventing and/or treating severe infections. In this study, we used an iTRAQ‐based quantitative proteomic approach to comprehensively characterize the membrane proteomes of monocytes before and after LPS exposure. We identified a total of 1651 proteins, of which 53.6% were membrane proteins. Ninety‐four percent of the proteins were quantified and 255 proteins were shown to be tightly regulated by LPS. Subcellular location analysis revealed organelle‐specific response to LPS exposure: more than 90% of identified mitochondrial membrane proteins were significant downregulated, whereas the majority of proteins from other organelles such as ER, Golgi and ribosome were upregulated. Moreover, we found that the expression of most receptors potentially involved in LPS signal pathway (CD14, toll‐like receptor 4, CD11/CD18 complex) were substantially decreased, while the expression of molecules involved in LPS neutralization were enhanced after LPS challenge. Together, these findings could be of significance in understanding the mechanism of LPS tolerance and provide values for designing new approaches for regulating monocytic responses in sepsis patients.
The Asia Oceania Human Proteome Organisation Membrane Proteomics Initiative. Preparation and characterisation of the carbonate‐washed membrane standard
Authors: Peng Lifeng , Kapp Eugene A. , Fenyö David , Kwon Min‐Seok , Jiang Pu , Wu Songfeng , Jiang Ying , Aguilar Marie‐Isabel , Ahmed Nikhat , Baker Mark S. , Cai Zongwei , Chen Yu‐Ju , Van Chi Phan , Chung Maxey C. M. , He Fuchu , Len Alice C. L. , Liao Pao‐Chi , Nakamura Kazuyuki , Ngai Sai Ming , Paik Young‐Ki , Pan Tai‐Long , Poon Terence C. W. , Hosseini Salekdeh Ghasem , Simpson Richard J. , Sirdeshmukh Ravi , Srisomsap Chantragan , Svasti Jisnuson , Tyan Yu‐Chang , Dreyer Florian S. , McLauchlan Danyl , Rawson Pisana , Jordan T. William
Published: May 2010

The Asia Oceania Human Proteome Organisation (AOHUPO) has embarked on a Membrane Proteomics Initiative with goals of systematic comparison of strategies for analysis of membrane proteomes and discovery of membrane proteins. This multilaboratory project is based on the analysis of a subcellular fraction from mouse liver that contains endoplasmic reticulum and other organelles. In this study, we present the strategy used for the preparation and initial characterization of the membrane sample, including validation that the carbonate‐washing step enriches for integral and lipid‐anchored membrane proteins. Analysis of 17 independent data sets from five types of proteomic workflows is in progress.
Reproducibility of the Physiological Cost Index among Individuals with a Lower‐Limb Amputation and Healthy Adults
Authors: Hagberg Kerstin , Tranberg Roy , Zügner Roland , Danielsson Anna
Published: May 2010

Background and Purpose. The physiological cost index (PCI) is a clinical measurement used to estimate the energy cost of walking. The reproducibility of the PCI has been questioned and no study has investigated the measurement error among individuals with a lower‐limb amputation. The aim was to investigate the test–retest reproducibility of the PCI in individuals with a lower‐limb amputation and healthy adults. Methods. The study comprised 28 individuals (20 males, eight females, mean age 49 years) with a unilateral amputation due to reasons other than vascular disease and 31 healthy volunteers (20 males, 11 females, mean age 47 years). PCI values were obtained by registering heart rate at rest and during level indoor walking for 5 minutes at a comfortable speed. A within‐day test–retest assessment was performed. Reproducibility analyses included intra‐class correlation, analyses of systematic differences between measurements, calculation of the smallest detectable change (SDC) and coefficient of variation (CV), and the results were finally visualized using Bland–Altman plots. Results. The reliability in terms of intra‐class correlation was excellent for both groups (0.966 and 0.948). In the amputee group, the PCI revealed a mean difference of 0.026 (p = 0.016) between tests (PCI = 0.555, standard deviation [SD] = 0.214 and PCI = 0.581, SD = 0.236, respectively). In the healthy group, there was no systematic difference between tests (PCI = 0.329, SD = 0.114 and PCI = 0.331, SD = 0.110, respectively). The SDC was 0.116 in the amputee group and 0.070 in the healthy group, giving a CV of 20.4% and 21.0%,respectively. Conclusions. The within‐day test–retest reproducibility of the PCI was excellent among individuals with lower‐limb amputations and healthy adults in terms of intra‐class correlation and acceptable in terms of agreement. The SDC, which was calculated for each group, should be considered when demonstrating an individual difference after an intervention. Copyright © 2010 John Wiley & Sons, Ltd.
Detection and refinement of encounter complexes for protein–protein docking: Taking account of macromolecular crowding
Authors: Li Xiaofan , Moal Iain H. , Bates Paul A.
Published: May 2010

Analysis of trajectories from our rigid‐body dynamics simulation package, BioSimz, is used to find regions on the surface of unbound proteins that form frequent and tenacious encounter complexes with their binding partner. Binding partners are significantly more likely to sojourn around true binding regions than around the remainder of the protein surface. This information is used to restrict the search space for flexible protein–protein docking using our SwarmDock algorithm, reducing the computational expense of docking, and improving or matching the ranking of successfully docked poses for all but four of 26 test cases. Running the simulations with external crowder proteins, at near physiological concentration, further enhances the binding region, compared to simulations without external crowders. Information gleaned from these simulations can give mechanistic insights into binding events. The application of these techniques to CAPRI targets 32 and 38–40 is discussed. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Theoretical study of the interaction between C2H5OH and mordenite zeolite by periodic density functional theory method
Authors: Nguyen Ngoc Ha , Le Minh Cam
Published: May 2010

The interaction of a single ethanol with pure‐silica and acid mordenite (MOR) has been investigated using density functional theory. Different interaction modes have been studied for three acid sites. All initial structures have been optimized by minimizing the total energy with respect to all lattice parameters and to the atomic coordinates. The nature of the ethanol–acid site complex has been discussed in detail. The strength of the adsorption is directly correlated to the local structural distortion of the MOR framework, especially of the acid site. By using partial density of states method, a detail in the distribution of density of states (orbital) has been obtained. An analysis of the differential charges has been performed, indicating substantial polarization effects for the acid site and for the ethanol molecule as well. Finally, the red‐shift of the harmonic OH stretching frequencies due to the interaction has been estimated. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Quantum chemical studies on prototautomerism of 1H‐imidazo[4,5‐c]pyridine
Authors: Yurdakul Şenay , Badoğlu Serdar
Published: May 2010

The structural features of the 1H‐imidazo[4,5‐c]pyridine (ICPY) tautomers and homodimers of the most stable tautomers have been studied by quantum chemical methods. FTIR and Raman spectra of the ICPY were recorded in the range of 4000–60 cm−1 and 3500–5 cm−1. The predominant tautomer among four possible isomers of ICPY were determined. The optimized geometries and vibrational frequencies of possible ICPY tautomers and dimers were computed by B3LYP/DFT method with 6‐311++G(d,p) and 6‐31G(d) basis sets. All vibrational frequencies assigned in detail with the help of total energy distribution (TED) and isotopic shifts. ICPY dimeric forms were also characterized according to their hydrogen bonding interactions, and it has been found that the most stable ICPY homodimer establishes moderate strong NH…N type hydrogen bond. 1H NMR, 13C NMR, and 15N NMR properties have been calculated for all tautomeric forms using the gauge independent atomic orbital (GIAO) method. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
The complexant shape effect on first (hyper)polarizability of alkalides Li+(NH2CH3)4M− (M = Li, Na, and K)
Authors: Xu Hong‐Liang , Wang Fang‐Fang , Chen Wei , Yu Guang‐Tao
Published: May 2010

In our previous work, new alkalides Li+(calix [4]pyrrole)M− with cup‐like complexant have been reported for the large static first hyperpolarizabilities (β0) (Chen et al., J Am Chem Soc 2006, 128, 1072). In this work, new inorganic alkalides are found by using a more flexible complexant, methylamine (NH2CH3)4. The structures with all real frequencies and β0 values of the inorganic alkalides Li+(cage [4]methylamine)M− (M = Li, Na, and K) are obtained at MP2 level. The result shows that these inorganic alkalides have more considerable β0 values to be 18,825 (M = Li) < 27,942 (M = Na) < 81,094 au (M = K), which are more than two times larger than those (10,969 ∼ 35,934 au) of the reported alkalides Li+(calix [4]pyrrole)M−. To understand this structure–property relationship, two cup‐like Li+(NH2CH3)4M− (M = Li, Na, and K) models are designed to compare their β0 values. By comparing the β0 values among the cup‐like alkalides Li+(calix [4]pyrrole)M−, Li+(NH2CH3)4M−, and cage‐like alkalides Li+(cage [4]methylamine)M− (M = Li, Na, and K), the complexant shape effect of alkalides has been revealed. It is found that the complexant shape is an important factor in large β0 values. Moreover, the monotonic dependences of β0 on the Li–M distance and the NBO charges of cation (Li+) and anions (M−) in inorganic alkalides Li+(cage [4]methylamine)M− have been shown. In this work, the frequency dependent first (hyper)polarizabilities are also determined. It is found that both the frequency dispersion and the effects of the electron correlation are strong. Moreover, the dependence of both the static and frequency dependent β on the atomic number of alkali metal anions is similar. This work provides a new way to understand the nature of high‐performance nonlinear optical (NLO) materials, and it is helpful to design new NLO materials. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011.
Microscopic description of small doped 3He clusters through the full‐configuration‐interaction nuclear orbital approach: The (3He)N‐Br2(X) case revisited
Authors: De Lara Castells María Pilar , Villarreal Pablo , Delgado‐Barrio Gerardo , Mitrushchenkov Alexander O.
Published: May 2010

We have completed our previous study on small (3He)N‐Br2(X) clusters (de Lara‐Castells et al., J Chem Phys (Communication) 2006, 125, 221101) by using larger one‐particle basis sets and an enhanced implementation of the full‐configuration‐ interaction nuclear orbital treatment to calculate ground and excited “solvent” states of small doped 3HeN clusters (de Lara‐Castells et al., J Chem Phys 2009, 131, 194101). Because of the inherent hard‐core interaction problem owing to the strong He–He repulsive potential at short distances, very large one‐particle basis sets are necessary to get converged results. Very similar results to those found for clusters with Cl2(B) as the dopant species have been found, owing more to the rather similar anisotropic T‐shaped character of the used He‐dopant potential energy surfaces than to the dominance of the He‐dopant attractive interaction over the He–He one in both cases. The results of the numerical testing by modifying the strength of the He–He potential interaction provide further evidences into the microscopic interactions holding the clusters together. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Preventing Nanoscale Wear of Atomic Force Microscopy Tips Through the Use of Monolithic Ultrananocrystalline Diamond Probes
Authors: Liu J. , Grierson D. S. , Moldovan N. , Notbohm J. , Li S. , Jaroenapibal P. , O'Connor S. D. , Sumant A. V. , Neelakantan N. , Carlisle J. A. , Turner K. T. , Carpick R. W.
Published: May 2010

Nanoscale wear is a key limitation of conventional atomic force microscopy (AFM) probes that results in decreased resolution, accuracy, and reproducibility in probe‐based imaging, writing, measurement, and nanomanufacturing applications. Diamond is potentially an ideal probe material due to its unrivaled hardness and stiffness, its low friction and wear, and its chemical inertness. However, the manufacture of monolithic diamond probes with consistently shaped small‐radius tips has not been previously achieved. The first wafer‐level fabrication of monolithic ultrananocrystalline diamond (UNCD) probes with <5‐nm grain sizes and smooth tips with radii of 30–40 nm is reported, which are obtained through a combination of microfabrication and hot‐filament chemical vapor deposition. Their nanoscale wear resistance under contact‐mode scanning conditions is compared with that of conventional silicon nitride (SiNx) probes of similar geometry at two different relative humidity levels (≈15 and ≈70%). While SiNx probes exhibit significant wear that further increases with humidity, UNCD probes show little measurable wear. The only significant degradation of the UNCD probes observed in one case is associated with removal of the initial seed layer of the UNCD film. The results show the potential of a new material for AFM probes and demonstrate a systematic approach to studying wear at the nanoscale.
DNA Minicircles Connected via G‐Quadruplex Interaction Modules
Authors: Gonçalves Diana P. N. , Schmidt Thorsten L. , Koeppel Martin B. , Heckel Alexander
Published: May 2010

G‐quadruplexes are becoming reliable alternative interaction modules for the construction of DNA nanoarchitectures due to their prompt inducibility by salts. In this Full Paper, we report the design and synthesis of two different DNA minicircles equipped with G‐rich appendixes that can self‐hybridize into a G‐quadruplex, which acts as a DNA recruiter and glue. Both minicircles, one containing a hairpin‐like G‐rich region and the other an open tuning‐fork‐like G‐rich region, have the potential to form DNA G‐nanoconstructs but only the tuning‐fork minicircle does so. Incubation of the tuning‐fork minicircle with Na+ and Ni2+ results in the formation of minicircle dimers, while K+ and Sr2+ unexpectedly induce the formation of multimers. Moreover, a catenated DNA nanoconstruct is obtained when the components of the hairpin minicircle are incubated with K+ or Na+ and assembled in a stepwise sequence. All nanoconstructs are visualized by atomic force microscopy.
Emx2 and Foxg1 Inhibit Gliogenesis and Promote Neuronogenesis
Authors: Brancaccio Marco , Pivetta Chiara , Granzotto Marilena , Filippis Carol , Mallamaci Antonello
Published: May 2010

Neural stem cells (NSCs) give rise to all cell types forming the cortex: neurons, astrocytes, and oligodendrocytes. The transition from the former to the latter ones takes place via lineage-restricted progenitors in a highly regulated way. This process is mastered by large sets of genes, among which some implicated in central nervous system pattern formation. The aim of this study was to disentangle the kinetic and histogenetic roles exerted by two of these genes, Emx2 and Foxg1, in cortico-cerebral precursors. For this purpose, we set up a new integrated in vitro assay design. Embryonic cortical progenitors were transduced with lentiviral vectors driving overexpression of Emx2 and Foxg1 in NSCs and neuronal progenitors. Cells belonging to different neuronogenic and gliogenic compartments were labeled by spectrally distinguishable fluoroproteins driven by cell type-specific promoters and by cell type-specific antibodies and were scored via multiplex cytofluorometry and immunocytofluorescence. A detailed picture of Emx2 and Foxg1 activities in cortico-cerebral histogenesis resulted from this study. Unexpectedly, we found that both genes inhibit gliogenesis and promote neuronogenesis, through distinct mechanisms, and Foxg1 also dramatically stimulates neurite outgrowth. Remarkably, such activities, alone or combined, may be exploited to ameliorate the neuronal output obtainable from neural cultures, for purposes of cell-based brain repair.