bluuebunny/crossref_metadata_2025 huggingface dataset:
NOx and soot reduction in diesel engine premixed charge compression ignition combustion: a computational investigation
Authors: Diwakar R , Singh S
Published: June 2008

The objective of the present work is to study soot-EGR and soot-NO x tradeoff for premixed charge compression ignition (PCCI) combustion at a light-load (4 bar BMEP) operation of a medium-duty, large-bore, direct-injection diesel engine using multi-dimensional computational analysis. The simulations are performed using KIVA-3V computer code coupled with reduced chemical kinetics. Low (40 per cent) to heavy (70 per cent) EGR rates are applied to study the effects of reduced intake oxygen concentration on combustion and emissions. Model predictions of cylinder pressure and emissions are first validated against experimental data. Model-predicted temporal and spatial evolution of in-cylinder mixture in φ— T coordinates is then used to explain the fundamentals of PCCI combustion and emissions. Using computational analysis, it is shown that lower exhaust soot emissions for the lower EGR dilution cases (45 per cent) are due to higher soot oxidation rates, and lower exhaust soot emissions for very high EGR rates (70 per cent) are due to lower soot formation rates. The trend seen in NO x emissions are primarily attributable to the inert effect of EGR dilution and varied ignition delay caused by varied percentages of oxygen in the intake mixture.
Study of the short-term cylinder wall temperature oscillations during transient operation of a turbo-charged diesel engine with various insulation schemes
Authors: Rakopoulos C D , Giakoumis E G , Rakopoulos D C
Published: June 2008

This work investigates the phenomenon of short-term temperature (cyclic) oscillations in the combustion chamber walls of a turbocharged diesel engine during transient operation after a ramp increase in load. For this purpose, an experimentally validated simulation code of the thermodynamic cycle of the engine during transient conditions is used. This takes into account the transient operation of the fuel pump and the development of friction torque using a detailed per degree crank angle submodel, while the equations for each cylinder are solved individually and sequentially. The thermodynamic model of the engine is appropriately coupled to a wall periodic heat conduction model, which uses the gas temperature variation as boundary condition throughout the engine cycle after being treated by Fourier analysis techniques. Various insulation schemes are examined (plasma spray zirconia, silicon nitride) for load-increase transient operation. The evolution of many variables during transients is depicted, such as amplitude of oscillation, depth where the swing dies out, or gradient of temperature swing. The investigation reveals many interesting aspects of transient engine heat transfer, regarding the influence that the engine wall material properties have on the values of cyclic temperature swings.
Lin-28 interaction with the Let-7 precursor loop mediates regulated microRNA processing
Authors: Newman Martin A. , Thomson J. Michael , Hammond Scott M.
Published: June 2008

A hallmark of mammalian embryonic development is the widespread induction of microRNA (miRNA) expression. Surprisingly, the transcription of many of these small, noncoding RNAs is unchanged through development; rather, a post-transcriptional regulatory event prevents accumulation of the mature miRNA species. Here, we present a biochemical framework for the regulated production of the Let-7 family of miRNAs. Embryonic cells contain a Drosha Inhibitor that prevents processing of the Let-7 primary transcript. This inhibitor specifically binds to conserved nucleotides in the loop region of the Let-7 precursor, and competitor RNAs that mimic the binding site restore Let-7 processing. We have identified the Drosha Inhibitor as the embryonic stem cell specific protein Lin-28. Lin-28 has been previously implicated in developmental regulatory pathways in Caenorhabditis elegans, and it promotes reprogramming of human somatic cells into pluripotent stem cells. Our findings outline a microRNA post-transcriptional regulatory network and establish a novel role for the miRNA precursor loop in the regulated production of mature Let-7.
Electrostatic interactions in the hairpin ribozyme account for the majority of the rate acceleration without chemical participation by nucleobases
Authors: Nam Kwangho , Gao Jiali , York Darrin M.
Published: June 2008

Molecular dynamics simulations using a combined quantum mechanical/molecular mechanical potential are used to determine the two-dimensional free energy profiles for the mechanism of RNA transphosphorylation in solution and catalyzed by the hairpin ribozyme. A mechanism is explored whereby the reaction proceeds without explicit chemical participation by conserved nucleobases in the active site. The ribozyme lowers the overall free energy barrier by up to 16 kcal/mol, accounting for the majority of the observed rate enhancement. The barrier reduction in this mechanism is achieved mainly by the electrostatic environment provided by the ribozyme without recruitment of active site nucleobases as acid or base catalysts. The results establish a baseline mechanism that invokes only the solvation and specific hydrogen-bonding interactions present in the ribozyme active site and provide a departure point for the exploration of alternate mechanisms where nucleobases play an active chemical role.
Capacity Provision Networks: Foundations of Markets for Sharable Resources in Distributed Computational Economies
Authors: Du Anna Ye , Geng Xianjun , Gopal Ram , Ramesh R. , Whinston Andrew B.
Published: June 2008

With the rapid growth of rich-media content over the Internet, content and service providers (SP) are increasingly facing the problem of managing their service resources cost-effectively while ensuring a high quality of service (QoS) delivery at the same time. In this research we conceptualize and model an Internet-based storage provisioning network for rich-media content delivery. This is modeled as a capacity provision network (CPN) where participants possess service infrastructures and leverage their topographies to effectively serve specific customer segments. A CPN is a network of SPs coordinated through an allocation hub. We first develop the notion of discounted QoS capabilities of storage resources. We then investigate the stability of the discount factors over time and the network topography using a test-bed on the Internet through a longitudinal empirical study. Finally, we develop a market maker mechanism for optimal multilateral allocation and surplus sharing in a network. The proposed CPN is closely tied to two fundamental properties of Internet service technology: positive network externality among cooperating SPs and the property of effective multiplication of capacity allocation among several distributed service sites. We show that there exist significant incentives for SPs to engage in cooperative allocation and surplus sharing. We further demonstrate that intermediation can enhance the allocation effectiveness and that the opportunity to allocation and surplus sharing can play an important role in infrastructure planning. In conclusion, this study demonstrates the practical business viability of a cooperative CPN market.
Research Note—On Vendor Preferences for Contract Types in Offshore Software Projects: The Case of Fixed Price vs. Time and Materials Contracts
Authors: Gopal Anandasivam , Sivaramakrishnan Konduru
Published: June 2008

Prior research has indicated that, on average, offshore vendors have higher profits associated with time and materials (T&M) contracts than fixed price (FP) contracts. This research raises two questions. First, Is the relative importance of various profit drivers different across two contractual regimes? Second, Does it follow that vendors unconditionally prefer T&M contracts for all projects? We address these questions by using data on 93 offshore projects completed by a leading Indian vendor. We use an endogenous switching regression framework and the program evaluation methodology to show that profit equations are distinctly different for the two contractual regimes. Using these two profit equations, we also identify contingencies under which the vendor prefers an FP contract to a T&M contract. We hypothesize that the vendor's ability leverage information asymmetry about capabilities and experiences translates into the vendor preferring FP contract to secure larger information rents. Our results support this hypothesis and suggest that the vendor would prefer the FP contract for larger and longer projects with larger teams. However, vendors would prefer a T&M contract when the risk of employee attrition from the project team is high. In addition, we discuss managerial implications of these results in the paper.
Addressing the What and How of Online Services: Positioning Supporting-Services Functionality and Service Quality for Business-to-Consumer Success
Authors: Cenfetelli Ronald T. , Benbasat Izak , Al-Natour Sameh
Published: June 2008

With the continued growth of business-to-consumer (B2C) e-business, online vendors are providing an increasing array of services that support and enhance their core products or services. For example, Amazon.com does not just sell books; it also enhances that core product with automated product recommendations, “wish list” tracking, order status updates, customer reviews, and many other valuable supporting services. These supporting services are made possible exclusively through the design and deployment of information technology (IT) to provide website supporting services functionality (SSF). In this paper, we define and develop the concept of B2C SSF and investigate how IT can support core products or services. We theorize the role that SSF plays in an environment where individuals who visit B2C websites are not only customers but also technology users. Given the unique online environment that amalgamates vendor services with information systems (IS), our model integrates theories from both services marketing and technology acceptance to help explain the behavior of these customers/users. In doing so, we investigate the role of the extensively researched concept of service quality in relation to SSF. Although service quality provides guidance for how supporting services should be provided (e.g., responsively and reliably), it does not address what those services are (e.g., product recommendations). SSF addresses this deficiency, thus providing both theoretical and practical benefits through a focus on IT design and deployment. The results of a field study support that SSF is an important predictor of customer beliefs and behavior, beyond that predicted by service quality alone. SSF is an important concept to consider—theoretically and practically—in IT-mediated B2C service.
Predictors of Formal Control Usage in IT Outsourcing Partnerships
Authors: Rustagi Sandeep , King William R. , Kirsch Laurie J.
Published: June 2008

Client control over the vendor has been identified as a critical factor in successfully managing information technology outsourcing relationships. Though prior studies have suggested that “how much” control is exercised has significant ramifications for individuals and firms, relatively few studies have operationalized and studied this important concept. In this study, we define the amount of formal control as the variety of mechanisms used by a client to exercise control over a vendor and the extent to which the mechanisms are used. We use literature on transaction cost economics and organizational control to build a model of the antecedents of the amount of formal control. The study uses data from 138 client-vendor matched pairs working in eight large, long-term, ongoing outsourcing arrangements to test specific hypotheses. The results suggest that clients who have technical or relationship management knowledge, or have high levels of trust in their vendors, use formal control mechanisms to a lesser extent. On the other hand, task uncertainty was found to be positively associated with the amount of formal control, and the degree of core competency involved in the outsourced activity was not found to be related to the amount of formal control. These results are discussed, and implications for research and practice are drawn.
Editorial Note
Authors: Sambamurthy Vallabh
Published: June 2008

The journal's reviewing system is being changed from a single-blind process to a double-blind process effective March 2008.
A bullock, a monkey and Robocop: an assessment of the directly elected mayor in English local government
Authors: Asquith Andy
Published: June 2008

This article examines the implementation of the directly elected mayor (mayor) in England. Following a short examination of the history of the mayoralty, the article addresses the impact of the 2000 Local Government Act. Introduced by a reforming Blair administration, the Act sought to radically transform the ways in which local government in England operated and introduced the concept of the mayor. As we shall see, the introduction of the mayor has not been without its problems. Despite these initial teething difficulties, it has nevertheless provided opportunities to demonstrate what can be achieved by this radical innovation. Finally, the article speculates about what the future might hold given the White Paper on local government leadership that was published in late 2006.
Markets in the public sector: when do they work, and what do we do when they don't?
Authors: Greener Ian
Published: June 2008

There is a danger that we have become so used to the idea of markets in the public sector that they become taken for granted. This article first problematises the terms ‘market’ and ‘public’, before going on to talk about markets as they are being used in present policy, and applying a morphogenetic-inspired analysis of their use. Finally, it attempts to work out when and where markets might work in the public sector, and what we might do in terms of public reform where they do not.
Listening, learning, steering: new governance, communication and interactive policy formation
Authors: Crozier Michael
Published: June 2008

Western political systems have undergone significant shifts in recent decades. In the era of post-war mass democracy governments governed and political communication informed. Now, however, governance includes non-government as well as government actors, and a communications dynamic pervades the entire political system. This article examines the integration of governance and communication, conceptualising the interactive strategies associated with new governance patterns in communications terms. The core argument is that the emergence of recursive forms of communication and knowledge production are indicative of systemic imperatives at work that are producing novel patterns of social coordination and policy formation.
‘Kinds of people’ and equality monitoring in the UK
Authors: Aspinall Peter J. , Mitton Lavinia
Published: June 2008

Over the last few decades social identities have grown in importance, ‘sexual orientation’ and ‘national identity’ being the latest to join the fold. While all jostle for official recognition, which of these identity groups is monitored – and in what settings – is of practical importance. Respondent burden, concerns about confidentiality and disclosure, and the lack in some cases of benchmark data raise issues around the feasibility of monitoring multiple ‘equality strands’. As most organisations have limited capacity to undertake such analysis, a broader repertoire of approaches needs to be considered if this process is to be more than a meaningless bureaucratic exercise.
The Open Method of Coordination as a ‘two-level game’
Authors: Büchs Milena
Published: June 2008

One of the most discussed issues surrounding the Open Method of Coordination (OMC) is the way in which it influences national social policies. This article argues that the question of influence is incorrectly posed. Instead, the OMC has to be understood as a ‘two-level game’ in which member state governments and non-governmental actors try to have an impact on the definition of the OMC objectives and, subsequently, strategically and selectively use the OMC in national policy-making processes. This, however, entails problems in terms of the transparency of policy-making processes and the accountability of national governments.
The Dynamics of Education Finance in Federal Systems: Cross-time Analyses
Authors: Cameron Stafanie H. , Hofferbert Richard I.
Published: June 2008

This article is concerned with the cross-time patterns of relationships between education funding, social change, and intergovernmental relations in four federal systems. The basic hypothesis of the research reported here is that the policy processes of the four federations – Canada, the Federal Republic of Germany, Switzerland, and the United States – are essentially similar. That is, the determinants of certain fiscal outputs of the policy processes are the same across the set of four nations. Not only do we hypothesize that the determinants of levels of education expenditures will be the same across the systems, we also predict that expenditure changes over time will be produced by similar forces across the subnational jurisdictions of all four countries. The comparability hypothesis will be examined and tested in several ways. We are first interested in expenditure differentials across the subnational units (provinces, Länder, cantons, and states) and how these differentials have changed in recent years. Second, we shall examine the policy impact of socioeconomic differences and change in these differences across subnational units. Finally, we will explore the patterns of change in fiscal responsibility among subnational and local governments, along with the determinants and some of the effects of that change.
Triiodothyronine utilizes phosphatidylinositol 3-kinase pathway to activate anti-apoptotic myeloid cell leukemia-1
Authors: Pietrzak Maciej , Puzianowska-Kuznicka Monika
Published: June 2008

Triiodothyronine (T3) regulates apoptosis in cells according to their developmental stage, cell type, and pathophysiological state. The molecular mechanisms of this regulation, however, have been largely unknown. In this work, we show that the expression of the myeloid cell leukemia-1 (MCL-1) protein, an anti-apoptotic member of B-cell lymphoma-2 (BCL-2) family, increases in thyroid hormone receptor-expressing human kidney-2 (HK2) cells upon 6-h incubation in 100 nM T3; we also describe the molecular mechanisms leading to this phenomenon. Transcription regulation assays performed in human embryonic kidney (HEK) 293 cells show that 100 nM T3 increases transcription from the MCL-1 promoter twofold in the presence of thyroid hormone receptor β1, but not of its α1 isoform. However, this increase is not a result of direct activation via the thyroid hormone-response element, TRE-DR4, located at the −998 to −983 position in this promoter; furthermore, the presence of 9-cis-retinoic acid receptor is not required. The promoter's activation is abolished in the presence of phosphatidylinositol 3-kinase (PI3-K) inhibitor, wortmannin. The −295 to −107 promoter fragment contains all sequences involved in T3-dependent activation of the MCL-1 promoter, and cAMP-responsive element located at the −262 to −255 position is a major mediator in this process. Therefore, MCL-1 expression is activated by T3, which increases its promoter activity by a non-genomic mechanism using the PI3-K signal transduction pathway. We propose that this is another mechanism by which T3 regulates apoptosis.
Testing Soil Encasing Materials for Measuring Hydraulic Conductivity of a Sandy‐Loam Soil by the Cube Methods
Authors: Bagarello V. , Sgroi A.
Published: June 2008

The Cube Method (CM) and the Modified Cube Method (MCM) were developed for measuring vertical (Kv) and horizontal (Kh) saturated hydraulic conductivity of a single soil sample. By these methods, a cube of soil is carved out in situ and a suitable material is applied to enclose the cube in a tightly fitting casing before moving the sample to the laboratory. Problems may be associated with the use of gypsum, originally used to encase soil. The suitability of molten wax and expandable polyurethane foam to encase a soil cube was tested for a sandy‐loam soil. Wax‐treated samples yielded lower conductivity results than untreated samples by a maximum factor of 3.7. The observed discrepancies were attributed, at least in part, to soil pore obstruction phenomena caused by wax. Using foam to fill a gap 60% full and partially preventing leakage of expanded foam from the gap was found to be appropriate to reach the following objectives: (i) filling completely the gap after foam expansion, (ii) preventing flow at the boundary between the foam cast and a smooth surface, (iii) minimizing both dry and wet soil compaction phenomena during foam expansion, (iv) minimizing foam intrusion into exposed pores of 1.0 × 10−3 to 3.0 × 10−3 m (intrusion depth ≤ 2.0 × 10−3 m), and (v) allowing removal of any intrusion by the detachment of the set foam from the treated surface. Applying foam to collect undisturbed soil samples yielded Kv results (7.41 × 10−5– 1.67 × 10−4 m s−1) falling in the range of a larger number of previously measured conductivities (2.06 × 10−5– 2.03 × 10−4 m s−1), and it showed that Kv was 2.3 times larger than Kh In conclusion, using wax is not recommended to obtain fully representative soil samples. Foam was a promising encasing material for the investigated soil.
Modeling Phosphate Adsorption by Agricultural and Natural Soils
Authors: Jiao You , Hendershot William H. , Whalen Joann K.
Published: June 2008

The nonideal competitive adsorption model (NICA) was developed from the Langmuir adsorption theory and the Freundlich empirical equation. It is well suited to describing ion adsorption in complex systems like soils, which have multiple ions, highly heterogeneous surfaces, and a variety of adsorption sites on the particle surfaces. It has been successfully used to model the binding of protons and metal ions to humic substances, but its application for the adsorption of anions to heterogeneous surfaces has not been documented. The purpose of this study was to adapt the NICA model to describe hydroxyl and phosphate adsorption. Results show that by considering two types of surface sites, the NICA model can provide an excellent fit (R2 > 0.99) of the hydroxyl adsorption data obtained from −11 to −4 of log[OH], which corresponds to soil pH from 3 to 10. By using the parameters generated from hydroxyl adsorption, including adsorption maxima (Qmax,OH), binding strength (KOH), and nonideality (m), the NICA model gave a remarkable goodness of fit (R2 > 0.98) for the phosphate adsorption data obtained at different pH values. The model sensitivity test showed that the Type 1 surface (SOH2+) has up to 100 times greater contribution to phosphate adsorption than the Type 2 surface (SOH). Thus, the model may be simplified into a three‐parameter model by only considering the Type 1 surface for phosphate adsorption in acidic soils. The adapted NICA model can thus describe phosphate adsorption combined with hydroxyl adsorption and the parameters (nPO4,1/nOH,1 < 1, where nPO4,1 accounts for nonideality of PO43− and nOH,1 accounts for nonideality of OH−, both on a Type 1 surface) reveal the multidentate binding of phosphate. It provides a promising tool for analyzing competitive anion adsorption processes in soils.
Carbonyl Reductase 3 (CBR3) Mediates 9-cis-Retinoic Acid-Induced Cytostatis and is a Potential Prognostic Marker for Oral Malignancy
Authors: Ohkura-Hada Shuri , Kondoh Nobuo , Hada Akiyuki , Arai Masaaki , Yamazaki Yutaka , Shindoh Masanobu , Kitagawa Yoshimasa , Takahashi Masayuki , Ando Toshifumi , Sato Yasunori , Yamamoto Mikio
Published: June 2008

The molecular mechanisms of growth suppression by retinoic acid (RA) were examined. Our results suggest that the cytostatic effects of RA could be mediated by the activation of endogenous CBR3 gene in oral squamous cell carcinomas (OSCCs), and the expression is a potential marker for oral malignancy.
Erie Land Lighthouse: A Microcosm of Nineteenth-Century Great Lakes Maritime History
Authors: Thomas Judith
Published: June 2008

The Erie Land Lighthouse was a visible link in the early eighteenth century western frontier trade network. Lighting the harbor entrance to Erie, Pennsylvania, from 1818 until the close of the century, the Erie Land Lighthouse contributed to the emergence of Erie as a vital shipping port connecting the Great Lakes to expanding inland markets. Constructed in 1818, the Erie Land Lighthouse (formerly, Presque Isle Lighthouse) was the first of a series of lighthouses built by the United States to aid navigation and promote shipping on the Great Lakes. As with its contemporaries, the original 1818 structure was replaced in 1858 by a taller lighthouse and a more elaborate keeper's residence. Structural flaws required the 1858 lighthouse to be replaced in 1867 by a third, which still stands today. The record of the Erie Land Lighthouse mirrors the history of similar facilities and processes across the Great Lakes. Unlike other locations, however, the Erie, Pennsylvania, site is archaeologically unique due to the presence of remnants of all phases of its construction and use history. Archaeological investigation of the first two sequent lighthouse structures on the site recovered a range of artifacts reflecting the government ownership of the lighthouse property, the site's advantageous location in a commercial hub, the effects of local and regional competition, and the day-to-day life of the lighthouse keepers. Details of the archaeological excavations at the Erie Land Lighthouse are provided and the site is placed in the larger context of lighthouse construction and use on the Great Lakes.
A Trace Element Analysis of New York Chert Sources
Authors: Rafferty Sean M. , Wood Candis , Rieth Christina B.
Published: June 2008

A trace element analysis of chert samples from the Schoharie Valley, New York State, is presented. This analysis focuses on the multi-component Pethick site and a sample of comparative sites within the state. Trace element analysis was conducted using energy dispersive X-ray fluorescence. Results indicate that: 1) most tools are made from local chert sources; 2) there is the potential for the presence of non-local cherts within the valley, with implications for interregional trade and exchange; and 3) exotic cherts can sometimes not be distinguished from local sources visually, necessitating trace element analysis. Planned directions for future analyses are presented.
Impact of ER gene polymorphisms on overweight and obesity in Down Syndrome
Authors: Ferrara Mara , Capozzi Laura , Russo Rosa
Published: June 2008

The impact of ER XbaI and PvuII α gene polymorphisms on overweight and obesity were studied in 77 subjects with Down Syndrome (DS), of which 32 were children (18 boys, 14 girls), mean age 8.7 ± 2.3 years, and 45 adolescents (28 boys, 17 girls) mean age 14 ± 2.5 years. Their lifestyle was compared to 40 healthy age-matched controls. DS subjects had significant lesser physical activity than controls (p<0.05) and a lower caloric intake than the recommended requirements, which was significantly lesser than controls (p<0.05). Body Mass Index (BMI), Arm Circumference (AC) and Triceps Skinfold Thickness (TST) were significantly higher in DS subjects than controls (p<0.05), while metabolic and cardiovascular parameters were not significantly different between the groups (p>0.05). The frequency of ER genotypes in DS subjects was compared with the healthy controls, finding that there was a high prevalence of XXER genotype in DS subjects. Children and adolescents with DS, lacking ER XbaI site, showed significantly higher BMI and body fat distribution than other XbaI genotypes. The lack of ER XbaI site can indicate added risk of obesity in DS. No differences in metabolic and cardiovascular parameters were observed among ER genotypes. However, childhood obesity is associated with increased cardiovascular risk.
The influence of LTS-4, a saponoside from Lysimachia thyrsiflora L., on human skin fibroblasts and human melanoma cells
Authors: Galanty Agnieszka , Michalik Marta , Sędek Łukasz , Podolak Irma
Published: June 2008

We investigated the effect of a triterpene saponoside from Lysimachia thyrsiflora L. upon the viability, proliferation, morphology and cell motility of human melanoma HTB-140 cells and human skin fibroblasts (HSFs). The compound, denoted LTS-4, decreased the viability and rate of cell growth of both cell types in a time-and dose-dependent manner, and proved cytotoxic against cancer cells at significantly lower concentrations than for fibroblasts. LTS-4 also affected the morphology of the examined cells, causing vacuolisation and actin cytoskeleton disintegration, and had an inhibitory effect on the tumour cell motility.
Defects in quantum dots of IIB–VI semiconductors
Authors: Babentsov V. , Sizov F.
Published: June 2008

This review discusses the properties of structural defects in quantum dots of IIB–VI semiconductors. A great part of this knowledge has been developed in the last years and combined with the improvement in passivation technologies has contributed significantly to the nanotechnology.

In this review we introduced the main characterization methods which are used for the study of defects in the nanoform of semiconductors, presented a short description of how native defects can influence the emission spectra, underlined the restrictions which the Auger and deep-level defect recombination imposes on the excitonic emission. We also highlighted the importance of the defect passivation associated with efficiency and photostability of devices.
Systems of sets with multiplicative asymptotic density
Authors: Jahoda Pavel , Pěluchová Monika
Published: June 2008

The authors define a notion of system of sets with multiplicative asymptotic density in this paper. A criterion and one necessary condition for a given system {A
i}i=1∞ to be a system with multiplicative asymptotic density is given. Properties of certain special types of systems of sets with multiplicative asymptotic density are treated.
On automorphisms of finite Abelian p-groups
Authors: Golasiński Marek , Gonçalves Daciberg
Published: June 2008

Let A be a finitely generated abelian group. We describe the automorphism group Aut(A) using the rank of A and its torsion part p-part A
p.

For a finite abelian p-group A of type (k
1, ..., k
n), simple necessary and sufficient conditions for an n × n-matrix over integers to be associated with an automorphism of A are presented. Then, the automorphism group Aut(A) for a finite p-group A of type (k
1, k
2) is analyzed.
Self-adjoint operators on inner product spaces over fields of power series
Authors: Keller Hans , Herminia Ochsenius
Published: June 2008

Theorems on orthogonal decompositions are a cornerstone in the classical theory of real (or complex) matrices and operators on ℝn. In the paper we consider finite dimensional inner product spaces (E, ϕ) over a field K = F((χ
1, ..., x
m)) of generalized power series in m variables and with coefficients in a real closed field F. It turns out that for most of these spaces (E, ϕ) every self-adjoint operator gives rise to an orthogonal decomposition of E into invariant subspaces, but there are some salient exceptions. Our main theorem states that every self-adjoint operator T: (E, ϕ) → (E, ϕ) is decomposable except when dim E is a power of 2 with exponent at most m, and ϕ is a tensor product of pairwise inequivalent binary forms. In the exceptional cases we provide an explicit description of indecomposable operators.
Deformation properties of one remarkable hypersurface by H. Takagi in ℝ4
Authors: Dušek Z. , Kowalski O.
Published: June 2008

We prove that the remarkable hypersurface found by H. Takagi in 1972 (as the first counter-example to the Nomizu conjecture on semi-symmetric spaces) is locally rigid.
Construction of a Portable Mini Luminescence-Measurement System Equipped with a Miniature X-Ray Generator
Authors: Takeuchi Tomoyuki , Shibutani Tomohiro , Hashimoto Tetsuo
Published: June 2008

For the purpose of both luminescence dosimetry and dating, a new portable mini automated luminescence-measuring system has been developed. The main parts of the new system consist of the stimulation unit, an irradiation unit and the photon detector. The size of the main measuring box is approximately 300x300x300 mm. In particular, to keep the electric power as low as possible, a miniature X-ray (Oxford, Eclipse II reflection target) generator and a metal-packaged photomultiplier tube (PMT) (Hamamatsu photonics, H7421-40) were adopted here. 16 blue LEDs were employed for the stimulation of quartz OSL. The same LED holder can be used for pulsed-OSL (P-OSL) measurements. The weight of the main part of this system was about 15 kg. In order to check the usefulness of the new system, red thermoluminescence (RTL) glow curves were measured to estimate the signal-to-noise ratio (S/N ratio) using a volcanic quartz sample. These results show that the new system improves the S/N ratio in comparison with an existing handmade system. The estimated RTL equivalent (or paleo) dose using quartz extracted from an archaeological roof tile of Shin-Yakushiji temple by means of the SAR protocol was in good agreement with previous measurements. This proves that the new system is suitable for practical use for RTL-measurements either for dosimetry or for dating with a high S/N ratio.
Determinant of Some Matrices of Field Elements
Authors: Nakamura Yatsuka
Published: June 2008

Determinant of Some Matrices of Field Elements

Here, we present determinants of some square matrices of field elements. First, the determinat of 2 * 2 matrix is shown. Secondly, the determinants of zero matrix and unit matrix are shown, which are equal to 0 in the field and 1 in the field respectively. Thirdly, the determinant of diagonal matrix is shown, which is a product of all diagonal elements of the matrix. At the end, we prove that the determinant of a matrix is the same as the determinant of its transpose.
Some Properties of Some Special Matrices. Part II
Authors: Yue Xiaopeng , Hu Dahai , Liang Xiquan
Published: June 2008

Some Properties of Some Special Matrices. Part II

This article provides definitions of idempotent, nilpotent, involutory, self-reversible, similar, and congruent matrices, the trace of a matrix and their main properties.
Several Differentiation Formulas of Special Functions. Part III
Authors: Li Bo , Zhang Yan , Liang Xiquan
Published: June 2008

Several Differentiation Formulas of Special Functions. Part III

In this article, we give several differentiation formulas of special and composite functions including trigonometric function, inverse trigonometric function, polynomial function and logarithmic function.
Multiplication of Polynomials using Discrete Fourier Transformation
Authors: Treyderowski Krzysztof , Schwarzweller Christoph
Published: June 2008

Multiplication of Polynomials using Discrete Fourier Transformation

In this article we define the Discrete Fourier Transformation for univariate polynomials and show that multiplication of polynomials can be carried out by two Fourier Transformations with a vector multiplication in-between. Our proof follows the standard one found in the literature and uses Vandermonde matrices, see e.g. [27].
Some Special Matrices of Real Elements and Their Properties
Authors: Liang Xiquan , Ge Fuguo , Yue Xiaopeng
Published: June 2008

Some Special Matrices of Real Elements and Their Properties

This article describes definitions of positive matrix, negative matrix, nonpositive matrix, nonnegative matrix, nonzero matrix, module matrix of real elements and their main properties, and we also give the basic inequalities in matrices of real elements.
Integrability and the Integral of Partial Functions from R into R1
Authors: Endou Noboru , Shidama Yasunari , Yamazaki Masahiko
Published: June 2008

Integrability and the Integral of Partial Functions from R into R1

In this paper, we showed the linearity of the indefinite integral the form of which was introduced in [11]. In addition, we proved some theorems about the integral calculus on the subinterval of [a,b]. As a result, we described the fundamental theorem of calculus, that we developed in [11], by a more general expression.
On the Representation of Natural Numbers in Positional Numeral Systems1
Authors: Naumowicz Adam
Published: June 2008

On the Representation of Natural Numbers in Positional Numeral Systems1

In this paper we show that every natural number can be uniquely represented as a base-b numeral. The formalization is based on the proof presented in [11]. We also prove selected divisibility criteria in the base-10 numeral system.
The Relevance of Measure and Probability, and Definition of Completeness of Probability
Authors: Zhang Bo , Yamazaki Hiroshi , Nakamura Yatsuka
Published: June 2008

The Relevance of Measure and Probability, and Definition of Completeness of Probability

In this article, we first discuss the relation between measure defined using extended real numbers and probability defined using real numbers. Further, we define completeness of probability, and its completion method, and also show that they coincide with those of measure.
Several Classes of BCI-algebras and their Properties
Authors: Ding Yuzhong
Published: June 2008

Several Classes of BCI-algebras and their Properties

I have formalized the BCI-algebras closely following the book [6], sections 1.1 to 1.3, 1.6, 2.1 to 2.3, and 2.7. In this article the general theory of BCI-algebras and several classes of BCI-algebras are given. MML identifier: BCIALG 1 , version: 7.8.04 4.81.962
Basic Properties of Determinants of Square Matrices over a Field1
Authors: Pąk Karol
Published: June 2008

Basic Properties of Determinants of Square Matrices over a Field1

In this paper I present basic properties of the determinant of square matrices over a field and selected properties of the sign of a permutation. First, I define the sign of a permutation by the requirement where p is any fixed permutation of a set with n elements. I prove that the sign of a product of two permutations is the same as the product of their signs and show the relation between signs and parity of permutations. Then I consider the determinant of a linear combination of lines, the determinant of a matrix with permutated lines and the determinant of a matrix with a repeated line. Finally, at the end I prove that the determinant of a product of two square matrices is equal to the product of their determinants. MML identifier: MATRIX11 , version: 7.8.04 4.81.962
Nickel‐Catalyzed Highly Selective Hydrovinylation of α‐Ketals of Vinylarenes
Authors: Zhang Qi , Zhu Shou‐Fei , Qiao Xiang‐Chen , Wang Li‐Xin , Zhou Qi‐Lin
Published: June 2008

A nickel‐catalyzed hydrovinylation of α‐ketal derivatives of vinylarenes has been developed, providing a new method for preparing functional olefins with a quarternary carbon center in high yields and selectivities.
Self‐Immobilizing Precatalysts: Norbornene‐Bridged Zirconium ansa‐Metallocenes
Authors: Polo Eleonora , Forlini Fabrizio , Bertolasi Valerio , Boccia Antonella Caterina , Sacchi Maria Carmela
Published: June 2008

We report here the synthesis of new tethered biscyclopentadienyl and bisindenyl zirconocenes, bearing one unsaturation on the interannular bridge, and their use as self‐immobilizing catalysts. They proved to be active catalysts towards ethylene polymerization in solution, with activities comparable to those displayed by commercial rac‐Et(Ind)2ZrCl2. When tested as self‐polymerization catalysts under suitable experimental conditions, they gave colored precipitates that, once reactivated with MAO, were significantly active in ethylene polymerization, although lower than those of the corresponding catalytic systems in solution. The molecular weights of the produced polymers were similar to those obtained with the same catalysts in solution, but their distribution resulted to be broader, with values typical of heterogeneous catalytic systems. From 13C NMR studies we had the first spectroscopic evidence of the actual incorporation of a metallocene of this type into a polymeric chain.
Enantioselective Synthesis of Phospholenes via Asymmetric Organocatalytic Alkene Isomerization
Authors: Hintermann Lukas , Schmitz Marco
Published: June 2008

An asymmetric synthesis of the 2,5‐diphenylphosphol‐2‐ene fragment (≥95% ee) has been realized via enantioselective Cinchona‐alkaloid catalyzed double bond isomerization of a meso‐2,5‐diphenylphosphol‐3‐ene amide to a 2,5‐diphenylphosphol‐2‐ene amide (up to 83% ee), followed by enantiomeric enrichment to ≥95% ee by crystallization. The 2,5‐diphenylphosphol‐2‐ene amide (a cyclic phosphinic acid amide) was hydrolyzed to the 2,5‐diphenylphosphol‐2‐ene acid (a cyclic phosphinic acid) with retention of configuration at C‐5.
Direct Copper‐Free Domino Conjugate Addition‐Cycloallylation using Organozinc Reagents
Authors: Komanduri Venukrishnan , Pedraza Fernando , Krische Michael J.
Published: June 2008

The Direct Approach: Enones possessing appendant allylic carbonates react directly with diorganozinc reagents in the presence of zinc diiodide [ZnI2] to provide 5‐ and 6‐membered ring products of tandem or domino conjugate addition‐cycloallylation in good to excellent yield. In a related copper‐free transformation, allylic carbonates are found to engage in direct allylic substitution with diorganozinc reagents.
Analysis of mixing in a Twin Cam mixer using smoothed particle hydrodynamics
Authors: Robinson Martin , Cleary Paul , Monaghan Joseph
Published: June 2008

Smoothed Particle Hydrodynamics (SPH) is a Lagrangian, particle‐based method that is well suited to industrial mixing simulations. Mass transport is simply the motion of the particles, and its grid‐free nature means that it can easily accommodate complicated geometries involving moving parts and sharp corners. This article describes 2D SPH simulations of a Twin Cam mixer and compares the results against experimental data and results from two published finite element method (FEM) simulations. To analyze the mixing processes in the Twin Cam mixer, we present a method for calculating the Finite‐Time Lyapunov Exponent (FTLE) using SPH particle data. The FTLEs can be used to locate the unstable and stable manifolds in the flow and indicate where mixing is either promoted or inhibited in the flow. We also present a local measure of how two or more fluids are “mixed” at a point in the domain. This is used to find the time‐scales of mixing over different regions in the domain and at different length‐scales. The purpose of the article is to evaluate the effectiveness of SPH, FTLEs, and our mixing measure in simulating and analyzing the mixing in a typical industrial mixer. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Occupational segregation as a determinant of US worker health
Authors: Chung‐Bridges Katherine , Muntaner Carles , Fleming Lora E. , Lee David J. , Arheart Kristopher L. , LeBlanc William G. , Christ Sharon L. , McCollister Kathryn E. , Caban Alberto J. , Davila Evelyn P.
Published: June 2008

Background

Racial segregation provides a potential mechanism to link occupations with adverse health outcomes.

Methods

An African‐American segregation index (IAA) was calculated for US worker groups from the nationally representative pooled 1986–1994 National Health Interview Survey (n = 451,897). Ranking and logistic regression analyses were utilized to document associations between IAA and poor worker health.

Results

There were consistent positive associations between employment in segregated occupations and poor worker health, regardless of covariate adjustment or stratification (e.g., age, gender, income, education, or geographic region). This association between segregation and poor health was stronger for White as compared to African‐American workers.

Conclusions

Occupational segregation negatively affects all workers. Potential mechanisms need to be identified through which occupational segregation may adversely impact worker health. Am. J. Ind. Med. 51:555–567, 2008. © 2008 Wiley‐Liss, Inc.
Nephrogenic diabetes insipidus in a patient with L1 syndrome: A new report of a contiguous gene deletion syndrome including L1CAM and AVPR2
Authors: Knops Noël B.B. , Bos Krista K. , Kerstjens Mieke , van Dael Karin , Vos Yvonne J.
Published: June 2008

We report on an infant boy with congenital hydrocephalus due to L1 syndrome and polyuria due to diabetes insipidus. We initially believed his excessive urine loss was from central diabetes insipidus and that the cerebral malformation caused a secondary insufficient pituitary vasopressin release. However, he failed to respond to treatment with a vasopressin analogue, which pointed to nephrogenic diabetes insipidus (NDI). L1 syndrome and X‐linked NDI are distinct clinical disorders caused by mutations in the L1CAM and AVPR2 genes, respectively, located in adjacent positions in Xq28. In this boy we found a deletion of 61,577 basepairs encompassing the entire L1CAM and AVPR2 genes and extending into intron 7 of the ARHGAP4 gene. To our knowledge this is the first description of a patient with a deletion of these three genes. He is the second patient to be described with L1 syndrome and NDI. During follow‐up he manifested complications from the hydrocephalus and NDI including global developmental delay and growth failure with low IGF‐1 and hypothyroidism. © 2008 Wiley‐Liss, Inc.
A multiplex family with possible metaphyseal Spahr‐type dysplasia and exclusion of RMRP and COL10A1 as candidate genes
Authors: Mégarbané André , Chouery Eliane , Ghanem Ismat
Published: June 2008

We report a consanguineous Lebanese family where six individuals had disproportionate short stature, short limbs, and bilateral genu varum that were apparent after 2 years of age. Major radiographic features in infancy included flared, cupped, and ragged metaphyses of all long bones, delayed maturation of the scaphoid, trapezoid, and trapezium bones, wide and slightly irregular ribs, short femoral necks, flat femoral heads, and irregularity of the iliac crest. Radiographs of an affected adult showed diminished metaphyseal changes and slightly short femoral necks, when compared to the younger patients. We suggest that this family is affected with the Spahr type of metaphyseal chondrodysplasia. Sequencing of RMRP, and a haplotype analysis using highly informative markers around the COL10A1 excluded both genes from being pathogenic in this family. We are aware of only two previous reports of families with clinical features similar to the Spahr type of metaphyseal chondrodysplasia. © 2008 Wiley‐Liss, Inc.
Johanson–Blizzard syndrome: Report of a novel mutation and severe liver involvement
Authors: Al‐Dosari Mohammed S. , Al‐Muhsen Saleh , Al‐Jazaeri Ayman , Mayerle Julia , Zenker Martin , Alkuraya Fowzan S.
Published: June 2008

Johanson–Blizzard syndrome (JBS) is a rare autosomal recessive condition characterized by pathognomonic facies and a constellation of other features most notably exocrine pancreatic insufficiency, oligodontia, growth retardation, hearing loss, mental retardation, scalp defects, hypothyroidism and imperforate anus. We report on an infant with classical JBS who also has unusually severe neonatal cholestatic liver disease that progressed to liver fibrosis and portal hypertension. Sequencing of UBR1 revealed a previously unreported homozygous missense mutation in a consensus splice acceptor site (IVS12‐1G > A). This report is the first to document severe liver involvement in JBS and raises the possibility that this could be a rare but genuine association. © 2008 Wiley‐Liss, Inc.