bluuebunny/crossref_metadata_2025 huggingface dataset:
Elastic-Plastic Stress Analysis of Pressure Vessels
Authors: Deng Yang-chun , Chen Gang
Published: July 2013

To save material, the safety factor of pressure vessel design standards is gradually decreased from 5.0 to 2.4 in ASME Boiler and Pressure Vessel Codes. So the design methods of pressure vessel should be more rationalized. Considering effects of material strain hardening and non-linear structural deformation, the elastic-plastic stress analysis is the most suitable for pressure vessels design at present. This paper is based on elastic-plastic theory and considers material strain hardening and structural deformation effects. Elastic-plastic stress analyses of pressure vessels are summarized. Firstly, expressions of load and structural deformation relationship were introduced for thin-walled cylindrical and spherical vessels under internal pressure. Secondly, the plastic instability for thin-walled cylindrical and spherical vessels under internal pressure were analysed. Thirdly, to prevent pressure vessels from local failure, the ductile fracture strain of materials was discussed.
Closed Form Solutions for Stress Intensity Factor Coefficients for Circumferential ID Surface Flaws in Cylinders in ASME Section XI Appendix A
Authors: Cipolla Russell C. , Lee Darrell R.
Published: July 2013

The stress intensity factor (KI) equations for a surface crack in ASME Section XI, Appendix A are based on non-dimensional coefficients (Gi) that allow for the calculation of stress intensity factors for a cubic varying stress field. Currently, the coefficients are in tabular format for the case of a surface crack in a flat plate geometry. The tabular form makes the computation of KI tedious when determination of KI for various crack sizes is pursued and a flat plate geometry is conservative when applied to a cylindrical geometry.

In this paper, closed-form equations are developed based on tabular data from API 579 (2007 Edition) [1] for circumferential cracks on the ID surface of cylinders. The closed-form equations provide G0 and G1 coefficients while G2 through G4 are obtained using a weight function representation for the KI solutions for a surface crack. These equations permit the calculation of the Gi coefficients without the need to perform tabular interpolation. The equations are complete up to a fourth order polynomial representation of applied stress, so that the procedures in Appendix A have been expanded. The fourth-order representation for stress will allow for more accurate fitting of highly non-linear stress distributions, such as those depicting high thermal gradients and weld residual stress fields.

It is expected that the equations developed in this paper will be added to the Appendix A procedures. With the inclusion of equations to represent Gi, the procedures of Appendix A for the determination of KI can be performed more efficiently without the conservatism of using flat plate solutions. This is especially useful in performing flaw growth calculations where repetitive calculations are required in the computations of crack size versus time.

The equations are relatively simple in format so that the KI computations can be performed by either spreadsheet analysis or by simple computer programming. The format of the equations is generic in that KI solutions for other geometries can be added to Appendix A relatively easily.
Interaction Effect Evaluation of Multiple Through Cracks in Ductile Fracture Process
Authors: Suga Kazuhiro , Miyazaki Katsumasa , Arai Yohei , Kikuchi Masanori
Published: July 2013

Study on the interaction effect of multiple cracks on the collapse load during ductile crack growth processes is important for the integrity evaluation of nuclear structure. The ductile fracture processes are well studied numerically by using Gurson’s constitutive equation and taking into account of void growth during plastic deformation. In this study, two through cracks are assumed to exist in a flat plate in tension and the interaction between two cracks is studied. The initial crack length, horizontal distance and vertical distance between two cracks are changed systematically. The interaction behavior between two cracks is studied precisely. Criteria to evaluate maximum load in the ductile fracture processes are discussed. The present study found H/l criteria can estimate the maximum load reasonably, and also the consideration of the effect of the horizontal distance between two cracks in H/l criteria may improve its estimation more reasonable. The effects on maximum load by changing the horizontal distance between two cracks are studied.
Application of Torsional Mode of Ultrasonic Guided Wave in Pressure Pipeline
Authors: Zuo Yantian , Tang Xiaoying , Yu Houde , Qian Yaozhou , Wang Jifeng
Published: July 2013

Ultrasonic guided wave technology is presented as a new non-destructive pipeline inspection method for its rapid, long distance inspection and applied to special pipelines which are inaccessible by other conventional NDT methods. It can be widely used in the field of long range pipeline inspection. Dispersion and attenuation characteristics of torsional modes of ultrasonic guided wave in pipeline are presented. Propagation characteristics of T (0, 1) mode at different frequencies are studied. T (0, 1) mode excited by utilizing the magnetostrictive ultrasonic guided wave detection system is applied to detect the defects of pipeline. It can be concluded that the surface condition of the pipeline, the T (0, 1) mode excitation of different patterns and frequency have great effects on defect detection and the distance of guided wave propagation. Multiple factors should be considered to select the optimal frequency and excitation patterns as pipeline inspection in field.
Research on Deformation-Induced Martensite of the Austenite Stainless Steel Bellows Based on Magnetism Testing Method
Authors: Sheng Shui-Ping , Han Shu-xin , Chen Hai-Yun , Wu Hong-Jun , Wang Fei , Liu Yan-lei
Published: July 2013

Stainless steel bellows expansion joint is an important part of city gas pipelines. In recent years, accidents occur frequently due to stress corrosion. The research on failure mechanism for bellows has high practical significance. According to magnetic variety of the deformation-induced martensite, the martensite phase content was tested by using the MP30E-S measurement instrument, for the bellows made of the SUS304 and SUS316L materials separately formed by machine-bulge method and SUS304 materials formed by hydraulic pressure method which there is or not a solution treatment respectively. The results showed that, there are great relations between the martensite phase content and materials, deformation rate, and heat treatment. The martensite phase content of SUS316L is less than SUS304, the more martensite phase content because the more deformation rate, there are less and even martensite phase after solution treatment.
Development of RBM Standard for Pressurized Equipments in Japan
Authors: Sakai Shinsuke , Shibasaki Toshikazu , Masatomo Hiroaki , Ishimaru Hiroshi , Sekine Kazuyoshi
Published: July 2013

Many industries such as the petroleum, chemical, gas, and power industries that use power tools for maintenance are concerned with risk-based maintenance (RBM) in Japan. To promote RBM activities in Japan, a committee for developing RBM standards was established at the High Pressure Institute of Japan (HPI) in 2001. Development of the RBM standards (HPIS) was completed this year. This paper describes the activities of the RBM committee and presents an outline of the published standards. The committee is composed of 35 members representing universities, the National Research Institutes, and the petroleum, chemical, power electric, and heavy industries. Two subcommittees have also been organized, one for the development of RBM standards (WG1) and one for the development of an RBM handbook (WG2). The aim of WG1 is to develop the basic specifications for RBM standards. Thus far, the RBM standard named HPIS Z106 has been published. This standard was constructed with reference to API RP580 [1] and was developed so that it can be adapted to the Japanese specific situation. The aim of WG2 is to develop a handbook for actual application of RBM, and the RBM handbook HPIS Z107 Technical Report (TR) has been published. This handbook is composed of the following four parts: Part 1: General Information, Part 2: Wall Thinning Damage Factors, Part 3: Stress Corrosion Cracking (SCC) Damage Factors, and Part 4: Other Damage Factors. In this handbook, a concept for likelihood evaluation called the Failure Probability Index (FPI) is introduced. The new concept is described here, as well as a procedure for evaluating the FPI. In recognition of the fact that, in addition to developing standards to promote RBM activities in Japan, human resource development is also important, an RBM personnel certification system has been developed by HPI. An outline of this activity is also given here.
Stationary Flat Steel Ribbon Wound Vessels for Storage of High Pressure Hydrogen
Authors: Zheng Jinyang , Liu Xianxin , Xu Ping , Liu Pengfei , Wei Chunhua , Ye Xiaoru
Published: July 2013

High pressure gaseous hydrogen (HPGH2) storage offers the simplest solution in terms of infrastructure requirements and has become the most popular and highly developed method. HPGH2 storage vessel is the key equipment for HPGH2 storage system. China issued the first national standard on HPGH2 storage vessel named “stationary flat steel ribbon wound vessels for storage of high pressure hydrogen” in 2011. Some crucial technical points are involved in this standard, such as material selection, design method for the shell’s thickness, mehod for determining the winding parameters and detection techniques for the attaching quality between the flat steel ribbon layers. In this paper, a brief introduction is given to the aforementioned technical points.
Relief Valve Stress and Fatigue Study Using Non-Linear Analysis
Authors: Griffin David , Kelly John , Bowie Gareth , Hunt David , Fletcher Andrew , Reed Gary , Hugill Peter
Published: July 2013

Non-linear elastic-plastic techniques have been used to study the level A operating conditions of a relief valve subject to a small number of severe thermal shock transients during operation. The analysis uses a detailed FE mesh verified to capture the elastic-plastic behaviour of the valve. In addition, short duration transient heat loading on the valve was calculated using computational fluid dynamics using a conjugate heat transfer approach.

The non-linear plasticity behaviour of the model was simulated using a kinematic hardening model incorporating non-linear hardening. Due to the very localised plasticity around small radius fillets in the model, a highly refined mesh strategy was needed. An innovative meshing strategy was therefore incorporated utilising a similar methodology to that used for fluid dynamics meshing; the fluid facing surfaces and nozzles were finely meshed with hexahedral elements, while parts of the internal bulk material were meshed using high order tetrahedral elements.

Primary strength was analysed using traditional elastic methods. The progressive distortion check was based on the elasto-plastic through-wall strain distribution and the fatigue analysis based on the equivalent strain range.
Investigation of Transient Thermal Analysis Computational Efficiency Improvements via Frequency Domain Methods
Authors: Banyay Gregory A. , Brigham John C. , Rudnyi Evgenii
Published: July 2013

During the operation of a Nuclear Steam Supply System (NSSS), the possibility exists for certain thermal transients to occur in the Reactor Coolant System (RCS). These transients exhibit some amount of periodicity in terms of temperature versus time. The current method of solving for temperature or thermal-mechanical stress states in the nuclear pressure vessel industry is by solving the governing equations in the time domain. For some analytical situations, significant computational savings could be realized by solving the thermal transient problem in the frequency domain. That is, the time, memory, and disk space required to solve the analysis is much less in the frequency domain than in the time domain. Two frequency domain methods are discussed in this paper. First, a Laplace-based model order reduction approach is applied to a reactor vessel component subjected to a representative thermal transient. Second, the feasibility of a Fourier-based spectral approach is discussed. For transient thermal analysis, it is shown that by employing model order reduction, significant computational savings can be realized with insignificant compromise in the accuracy of results.
Analysis of 4” Schedule 160 Pipe With a Wall Thinning Subject to Torsion, Bending and Pressure Loads
Authors: Bezensek Bostjan
Published: July 2013

Pipes with local wall thinning can be simultaneously subject to multi-axial loads such as the internal pressure loads, axial loads, bending and torsion (twist) moments. Continued operation of such items makes use of fitness-for-service assessments using codes such as the ASME Boiler and Pressure vessel Code, Section XI. Currently the non-mandatory Appendix C of the Code gives guidance for performing assessment for various modes of failure. However in the current guidance there is no provision for inclusion of the torsion loads for either planar (crack) or non-planar (wall thinning) type flaws under predominant membrane and bending loading.

This paper is a continuation of the study reported at the earlier PVP conferences, whereby the intent is to provide guidance on inclusion of small amounts of torsion with the dominant pressure and bending loading for a pipe containing a wall thinning. In this paper the results are reported for a 4″ (100mm) nominal diameter Schedule 160 pipe. Two shapes of the wall thinning are examined; a cylindrical with round edges and an ellipsoidal shape. These are chosen to span a range of real shapes. The limits on the applicability of the equivalent moment, defined as the root of the sum of the squares (RSS) in construction codes is presented in terms of the wall thinning dimensions.
Alternative Approach for Qualification of Temperbead Welding in the Nuclear Industry
Authors: McCracken Steven L. , Smith Richard E.
Published: July 2013

Temperbead welding is common practice in the nuclear power industry for in-situ repair of quenched and tempered low alloy steels where post weld heat treatment is impractical. The temperbead process controls the heat input such that the weld heat-affected-zone (HAZ) in the low alloy steel is tempered by the welding heat of subsequent layers. This tempering eliminates the need for post weld heat treatment (PWHT). Unfortunately, repair organizations in the nuclear power industry are experiencing difficulty when attempting to qualify temperbead welding procedures on new quenched and tempered low alloy steel base materials manufactured to modern melting and deoxidation practices. The current ASME Code methodology and protocol for verification of adequate fracture toughness in materials was developed in the early 1970s. This paper reviews typical temperbead qualification results for vintage heats of quenched and tempered low alloy steels and compares them to similar test results obtained with modern materials of the same specification exhibiting superior fracture toughness.
Safety Assessment of Cold Welding Defect in Electro-Fusion Joint of Polyethylene Pipe
Authors: Shi Jianfeng , Zheng Jinyang , Guo Weican , Xu Cheng
Published: July 2013

Cold welding defect is the most common defect in electro-fusion (EF) joint for connecting polyethylene (PE) pipe. In our previous study[1], the cold welding defect is successfully inspected by an Eigen-line method based on phased array ultrasonic testing technology. However, small amount of research has been reported on the acceptance criterion of cold welding defect in EF joint. In this paper, the bonding strength of EF joint is measured using a peeling test. The bonding energy of welding interface is calculated both by phenomenological model and deformation energy analysis method. EF joints with different degrees of cold welding are made and used for peeling tests. The results show that the bonding energy of fused interface rises rapidly after bonding and then goes through a plateau region. The starting point of the plateau region in the bonding energy vs. welding time curve is regarded as the minimum required welding time of EF joint. Based on bilinear fitting, the acceptable criterion of cold welding defect is proposed.
Comparison of Experiment and Calculation on Fatigue Crack Growth for Transformed Surface Flaw
Authors: Hasegawa Kunio , Li Yinsheng , Miyazaki Katsumasa , Saito Koichi
Published: July 2013

If a subsurface flaw is located near a component surface, the subsurface flaw is transformed to a surface flaw in accordance with a flaw-to-surface proximity rule. The re-characterization process from subsurface to surface flaw is adopted in all fitness-for-service (FFS) codes. However, the criteria of the re-characterizations are different among the FFS codes. Cyclic tensile experiment was conducted on a carbon steel flat plate with a subsurface flaw at ambient temperature. The objective of this paper is to compare the experiment and calculation of fatigue crack growth behavior for a subsurface flaw and the transformed surface flaw, and to confirm the flaw-to-surface proximity rule defined by ASME Code Section XI and JSME S NA1 Code.
ASME Piping Code-Based Stress Analysis Procedure and a Comparison With the Italian Code
Authors: Grisolia Ottaviano
Published: July 2013

The procedure proposed applies to evaporator section of bottom-supported heat-recovery steam generators (HSRG): It includes classical methods for the static analysis of the lower header based on ASME Power Piping code B31.1 [1] and a computer-modeled flexibility analysis with a preliminary stress evaluation using both Italian and ASME pressure formulae. The stability of the harp high-temperature components may be critical because of their longitudinal dimensions, thermal expansions and loading. So, further elements of engineering choices may help obtaining good design of the header-tube assembly (harp).
Application of the System Based Code Concept to the ASME Code for Liquid Metal Reactors
Authors: Asayama Tai , Takaya Shigeru , Morishita Masaki
Published: July 2013

The System Based Code (SBC) which was initially proposed by Asada forms the basis of the development of a set of codes and standards in Japan that fully take advantage of the potential of liquid metal reactors (LMRs). The concept of SBC is also being elaborated within the American Society of Mechanical Engineers (ASME) as a promising way that improves current codes and standards by allowing significantly wider technical options with various advantages both in Sections III and XI through bridging them. This paper illustrates an envisioned scheme for code rules for new reactors based on the SBC concept that could be also implemented in ASME Boiler and Pressure Vessel Codes. The outline of technologies needed to materialize the concept such as “Break Size Limitation Analysis (BSLA)” and structural reliability evaluation are also described. Recent discussions in ASME indicate that efforts on drafting code rules based on the SBC concept will soon take place in ASME.
A Fracture Mechanics Evaluation of BWR Vessel Water Level Instrumentation Nozzle P-T Curve Assessment Including Impact of Irradiation Effects
Authors: Mehta Hardayal S. , Tilly Lori J. , Sampson Donald A.
Published: July 2013

This paper describes the evaluation performed to determine the bounding T-RTNDT for the Boiling Water Reactor (BWR) Water Level Instrumentation (WLI) nozzle for use in establishing reactor pressure vessel Pressure-Temperature (P-T) curves. The evaluation used finite element based fracture mechanics to augment the methods described in the ASME Boiler & Pressure Vessel Code, Section XI, Appendix G. A 3-D finite element linear elastic fracture mechanics analysis was conducted to determine the mode I stress intensity factor at the tip of a 1/4 thickness postulated flaw in the nozzle blend radius. Also included is a general discussion on the impact on the P-T curves of the postulated irradiation shift in RTNDT at the WLI nozzle.
Determination of Material Damping Values for High Density Polyethylene Pipe Materials
Authors: Munson Douglas , Adams Timothy M. , Hall Siegrid
Published: July 2013

For corroded piping in low temperature systems, such as service water systems in nuclear power plants, replacement of carbon steel pipe with High Density Polyethylene pipe is a cost-effective solution. Polyethylene pipe can be installed at much lower labor costs than carbon steel pipe and High Density Polyethylene pipe has a much greater resistance to corrosion. This paper presents the results of Electric Power Research Institute sponsored testing to determine material damping values for High Density Polyethylene pipe material. This was determined by experimental methods using the log decrement approach. Cantilevered beam samples were deflected, released and the resulting free vibration response was recorded. The possible relationship of the damping value to the natural frequency and the stress level of the test samples is also studied. The results of the testing are presented along with suggested damping values to be used in the seismic analysis of High Density Polyethylene piping.
Buried Piping: Managing the Challenge
Authors: Angell Peter , Moir Michelle , Munson Douglas , Berger Mike , Barton Robert
Published: July 2013

Nuclear utilities have many kilometres of piping buried in a relatively small physical area resulting in what has been called a “spaghetti bowl”. Until recently, much of this piping has been neglected and considered “out of sight / out of mind” therefore given a low operational impact. However, current failures have raised the profile of buried piping maintenance with both utilities and regulators.

Buried piping programs face many of the challenges familiar to well run maintenance programs, but these challenges are compounded for a number of reasons. This paper will discuss how Atomic Energy of Canada Limited (AECL) Nuclear Laboratories have partnered with utilities, service providers, CANDU Owners Group (COG), and the Electric Power Research Institute (EPRI) to provide support to the development and implementation of maintenance programs for buried piping.

Initially, AECL developed station strategy manuals to establish a mechanism to ensure a proficient ongoing program. As part of this program, extensive data on the systems was collected using station records. This data was then used to produce risk informed assessments, with the help of EPRI’s BPWORKS™ software, and ultimately the selection of inspection locations. Lessons learned from this work have not only been integrated into the station’s buried piping program, but also incorporated into improvements to the EPRI BPWORKS software.
Application of Water Jet Peening on Pre-Cracked Nickel Based Alloy and Stainless Steel
Authors: Morinaka Ren , Hasegawa Kunihiro , Saito Noboru , Yoshikubo Fujio , Kanno Akihiro
Published: July 2013

Water Jet Peening (WJP) has been widely applied to Japanese nuclear power plants since 1999 in order to mitigate stress corrosion cracking (SCC) generation on SCC susceptible material used their reactors as an approved mechanical mitigation technique against SCC [1].

Laboratory data shows that WJP has an effect to mitigate or suppress shallow crack propagation if the achieved compression depth is deeper than the crack, and that WJP has no adverse effect on pre-existing cracks on the mitigated surface, such as crack propagation during WJP treatment or acceleration effect after its treatment [2]. However, there was no field experience of applying WJP on cracked surfaces of operating reactor internals since we removed the crack(s) as the practice in Japan was to remove the crack prior to WJP implementation.

When observed crack can be left as is according to its profile, it is required to perform the crack sizing periodically by Ultrasonic Testing in order to monitor its propagation. In order to apply WJP on the cracked surface, additional testing was needed to clarify that no adverse effect on UT sizing capability after WJP will be observed. The Japan Atomic Power Company (JAPC) and Hitachi-GE Nuclear Energy, Ltd. (HGNE) have performed several tests about this UT crack sizing test before and after WJP treatment and other related test before its field application.
Empirical correlation for minority carrier lifetime to defect density profile in germanium on silicon grown by nanoscale interfacial engineering
Authors: Sheng Josephine J. , Leonhardt Darin , Han Sang M. , Johnston Steven W. , Cederberg Jeffrey G. , Carroll Malcolm S.
Published: July 2013

High-quality Ge-on-Si heterostructures have been explored for many applications, including near infrared photodetectors and integration with III–V films for multijunction photovoltaics. However, the lattice mismatch between Ge and Si often leads to a high density of defects. Introducing annealing steps prior to and after full Ge island coalescence is found to reduce the defect density. The defect density in Ge is also found to decrease with increasing dopant density in Si substrates, likely due to the defect pinning near the Ge-Si interface by dopants. The authors establish an empirical correlation between the minority carrier lifetime (τG) and the defect density in the Ge film (ρD) as a function of distance from the Ge-Si interface: τGe = C/ρD, where C is a proportionality constant and a fitting parameter which is determined to be 0.17 and 0.22 s/cm2 for Ge films grown on low-doped, high-resistivity Si substrates and high-doped, low-resistivity Si substrates, respectively. The effective minority carrier lifetime measured as a function of Ge film thickness is then related to the recombination velocity on Ge film surface, average minority carrier lifetime within Ge film, and recombination velocity at the Ge-Si interface. Using this relation, the authors estimate the Ge-Si interface recombination velocity for Ge films grown on low-doped, high-resistivity and high-doped, low-resistivity Si substrates to be 220 and 100 cm/s, respectively.
Transforming Growth Factor–β Signaling in T Cells Promotes Stabilization of Atherosclerotic Plaques Through an Interleukin-17–Dependent Pathway
Authors: Gisterå Anton , Robertson Anna-Karin L. , Andersson John , Ketelhuth Daniel F. J. , Ovchinnikova Olga , Nilsson Stefan K. , Lundberg Anna M. , Li Ming O. , Flavell Richard A. , Hansson Göran K.
Published: July 2013

Enhanced TGF-β signaling may promote plaque stability and prevent clinical manifestations of atherosclerosis.
Assessing NIH’s Big Idea
Authors: Terry Sharon F. , Leshner Alan I.
Published: July 2013

Central leadership and creative collaborations will enhance the harvest of the U.S. Clinical and Translational Science Award network.
Two Heme-Dependent Terminal Oxidases Power Staphylococcus aureus Organ-Specific Colonization of the Vertebrate Host
Authors: Hammer Neal D. , Reniere Michelle L. , Cassat James E. , Zhang Yaofang , Hirsch Amanda O. , Indriati Hood M. , Skaar Eric P.
Published: July 2013

Staphylococcus aureus
is a significant cause of infections worldwide and is able to utilize aerobic respiration, anaerobic respiration, or fermentation as the means by which it generates the energy needed for proliferation. Aerobic respiration is supported by heme-dependent terminal oxidases that catalyze the final step of aerobic respiration, the reduction of O
2
to H
2
O. An inability to respire forces bacteria to generate energy via fermentation, resulting in reduced growth. Elucidating the roles of these energy-generating pathways during colonization of the host could uncover attractive therapeutic targets. Consistent with this idea, we report that inhibiting aerobic respiration by inactivating heme biosynthesis significantly impairs the ability of
S. aureus
to colonize the host. Two heme-dependent terminal oxidases support aerobic respiration of
S. aureus
, implying that the staphylococcal respiratory chain is branched. Systemic infection with
S. aureus
mutants limited to a single terminal oxidase results in an organ-specific colonization defect, resulting in reduced bacterial burdens in either the liver or the heart. Finally, inhibition of aerobic respiration can be achieved by exposing
S. aureus
to noniron heme analogues. These data provide evidence that aerobic respiration plays a major role in
S. aureus
colonization of the host and that this energy-generating process is a viable therapeutic target.

IMPORTANCE
Staphylococcus aureus
poses a significant threat to public health as antibiotic-resistant isolates of this pathogen continue to emerge. Our understanding of the energy-generating processes that allow
S. aureus
to proliferate within the host is incomplete. Host-derived heme is the preferred source of nutrient iron during infection; however,
S. aureus
can synthesize heme
de novo
and use it to facilitate aerobic respiration. We demonstrate that
S. aureus
heme biosynthesis powers a branched aerobic respiratory chain composed of two terminal oxidases. The importance of having two terminal oxidases is demonstrated by the finding that each plays an essential role in colonizing distinct organs during systemic infection. Additionally, this process can be targeted by small-molecule heme analogues called noniron protoporphyrins. This study serves to demonstrate that heme biosynthesis supports two terminal oxidases that are required for aerobic respiration and are also essential for
S. aureus
pathogenesis.
Improving continence services for older people from the service-providers’ perspective: a qualitative interview study
Authors: Orrell Alison , McKee Kevin , Dahlberg Lena , Gilhooly Mary , Parker Stuart
Published: July 2013

Objective

To examine in depth the views and experiences of continence service leads in England on key service and continence management characteristics in order to identify and to improve our understanding of barriers to a good-quality service and potential facilitators to develop and to improve services for older people with urinary incontinence (UI).

Design

Qualitative semistructured interviews using a purposive sample recruited across 16 continence services.

Setting

3 acute and 13 primary care National Health Service Trusts in England.

Participants

16 continence service leads in England actively treating and managing older people with UI.

Results

In terms of barriers to a good-quality service, participants highlighted a failure on the part of commissioners, managers and other health professionals in recognising the problem of UI and in acknowledging the importance of continence for older people and prevalent negative attitudes towards continence and older people. Patient assessment and continence promotion regardless of age, rather than pad provision, were identified as important steps for a good-quality service for older people with UI. More rapid and appropriate patient referral pathways, investment in service capacity, for example, more trained staff and strengthened interservice collaborations and a higher profile within medical and nurse training were specified as being important facilitators for delivering an equitable and high-quality continence service. There is a need, however, to consider the accounts given by our participants as perhaps serving the interests of their professional group within the context of interprofessional work.

Conclusions

Our data point to important barriers and facilitators of a good-quality service for older people with UI, from the perspective of continence service leads. Further research should address the views of other stakeholders, and explore options for the empirical evaluation of the effectiveness of identified service facilitators.
Phthalocyanine-based hybrid materials for chemosensing
Authors: Bouvet Marcel , Gaudillat Pierre , Suisse Jean-Moïse
Published: July 2013

In the present review, we show how the chemical variability of phthalocyanines allowed to synthesize a broad range of hybrid materials. The combination of phthalocyanines or related derivatives with polymers or carbonaceous materials led to efficient chemical sensors. It is shown how the incorporation of macrocyclic molecules in hybrid materials highly modifies the structural and morphological characteristics of the materials. Rugosity, specific surface and porosity being key parameters in the analyte-sensing material interactions, these modifications highly improve the performance of chemical sensors. This is the reason why they are particularly promising materials for the development of new chemical sensors, associated with electrochemical, conductometric or optical transducers.
Density functional theory prediction for the second-order nonlinear optical responses of phenanthroline-fused phthalocyanine derivatives
Authors: Chen Chao , Zhang Lijuan , Zhao Luyang , Qi Dongdong , Jiang Jianzhuang
Published: July 2013

A series of unsymmetrical phenanthroline-fused phthalocyanine derivatives including Zn [ Pc ( Phen )], Zn [ Pc ( Phen )2], Zn [ Pc ( Phen )3], Zn [ Pc ( NH2)6( Phen )], Zn [ Pc ( NH2)4( Phen )2], Zn [ Pc ( NH2)2( Phen )3], Zn [ PcF6( Phen )], Zn [ PcF4( Phen )2], and Zn [ PcF2( Phen )3] were designed to explore their properties of geometric and electronic structures, electronic absorption spectra, and second-order nonlinear responses under density functional theory and time-dependent density functional theory calculations. The computational results show that the peripheral substituents with push-pull effect could obviously change the π–π* transitions, leading to a tunable absorption region in the range between 300–800 nm. The hyperpolarizabilities were carefully investigated using CP-DFT method, revealing the size effect and clarifying the limit when expanding the conjugated system is employed to improve the hyper-Rayleigh scattering response coefficient (βHRS). According to the results, the NH2-substitued phenanthroline-fused phthalocyanines are considered as ideal NLO blocking materials with large βHRS.
MATHEMATICAL-ARTIFICIAL NEURAL NETWORK HYBRID MODEL TO PREDICT ROLL FORCE DURING HOT ROLLING OF STEEL
Authors: RATH S. , SENGUPTA P. P. , SINGH A. P. , MARIK A. K. , TALUKDAR P.
Published: July 2013

Accurate prediction of roll force during hot strip rolling is essential for model based operation of hot strip mills. Traditionally, mathematical models based on theory of plastic deformation have been used for prediction of roll force. In the last decade, data driven models like artificial neural network have been tried for prediction of roll force. Pure mathematical models have accuracy limitations whereas data driven models have difficulty in convergence when applied to industrial conditions. Hybrid models by integrating the traditional mathematical formulations and data driven methods are being developed in different parts of world. This paper discusses the methodology of development of an innovative hybrid mathematical-artificial neural network model. In mathematical model, the most important factor influencing accuracy is flow stress of steel. Coefficients of standard flow stress equation, calculated by parameter estimation technique, have been used in the model. The hybrid model has been trained and validated with input and output data collected from finishing stands of Hot Strip Mill, Bokaro Steel Plant, India. It has been found that the model accuracy has been improved with use of hybrid model, over the traditional mathematical model.
Insights into the origin of the thermal springs of Bath and Bristol, England, from geophysical data
Authors: McCann C. , Mann A. C. , McCann D. M. , Kellaway G. A.
Published: July 2013

The thermal springs of Bath, England, produce 1.25 Ml day
−1
of water at 46.5 °C. The spring at Hotwells, Bristol, England, 15 km to the west, is estimated to produce between 0.17 and 0.39 Ml day
−1
of water at a temperature between 22.8 and 24.4 °C. Published research suggests that the waters originate in the Mendip Hills, SW of Bath and Bristol, and are heated by geothermal energy within the Carboniferous Limestone basin (‘The Mendips Model’). The exact paths of the waters to the springs have not been established. We interpreted seismic reflection data for the urban district of Bath and for the Radstock Basin to the south of Bath. By combining the geophysical interpretations with published geological data we have established a potential route through the Carboniferous Limestone reaching sufficient depths for the waters to attain the required temperatures. We imaged a steeply dipping, fractured region of Carboniferous Limestone coincident with the valley of the River Avon and propose that this is the feature by which the thermal waters can rise rapidly to the surface, providing an explanation for the existence of these unique springs. We have incorporated these new aspects of the Mendip Model into the ‘Mendip–Avon Fracture Zone Model’.
Gas generation and accumulation by aquifer drawdown and recharge in the London Basin
Authors: Standing J. , Ghail R. , Coyne D.
Published: July 2013

Air at high pressure has recently been encountered during ground investigation borehole drilling for the Thames Tideway project in London. The air was released from within the Upnor Formation (at the base of the Lambeth Group beds), which is at the top of the Lower Aquifer. Cavitation within the granular beds of the Lower Aquifer would have occurred as a consequence of drawdown from the extensive water extraction that began at the start of the nineteenth century, resulting in the water table dropping by almost 70 m. Estimated historical pore pressure profiles are postulated and the cavitation process that occurred, along with the subsequent pressurization of the air during recharge that has occurred in recent years, are discussed using behavioural concepts from unsaturated soil mechanics. The hypotheses are corroborated by a series of simple column experiments where the processes are modelled using analogous soils. Engineering implications of the presence of the pressurized air are discussed: besides the potential for borehole blow-out, another serious consideration is the depletion of oxygen from the trapped air by chemical reaction with the soil, increasing the risk of confined space hypoxia.
GCN2 regulates the CCAAT enhancer binding protein beta and hepatic gluconeogenesis
Authors: Xu Xu , Hu Jingjie , McGrath Barbara C. , Cavener Douglas R.
Published: July 2013

Mice deficient for general control nondepressible-2 ( Gcn2) either globally or specifically in the liver display reduced capacity to maintain glucose homeostasis during fasting, suggesting the hypothesis that GCN2 may regulate gluconeogenesis (GNG), which normally plays a key role maintaining peripheral glucose homeostasis. Gcn2-deficient mice exhibit normal insulin sensitivity and plasma insulin but show reduced GNG when administered pyruvate, a gluconeogenic substrate. The basal expression of phospho enolpyruvate carboxykinase, a rate-limiting enzyme in GNG, is abnormally elevated in Gcn2 knockout ( KO) mice in the fed state but fails to be further induced during fasting. The level of tricarboxylic acid cycle intermediates, including malate and oxaloacetate, and the NADH-to-NAD+ratio are perturbed in the liver of Gcn2 KO mice either in the fed or fasted state, which may directly impinge upon GNG. Additionally, the expression of the CCAAT enhancer-binding protein-β (C/EBPβ) in the liver fails to be induced in Gcn2 KO mice after 24 h fasting, and the liver-specific Cebpβ KO mice show reduced fasting GNG similar to that seen in Gcn2-deficient mice. Our study demonstrates that GCN2 is important in maintaining GNG in the liver, which is likely to be mediated through regulation of C/EBPβ.
Adult-onset obesity induced by early life overnutrition could be reversed by moderate caloric restriction
Authors: Liu Hung-Wen , Srinivasan Malathi , Mahmood Saleh , Smiraglia Dominic J. , Patel Mulchand S.
Published: July 2013

Overnutrition during the suckling period (small litter, SL) results in the development of adult-onset obesity. Our aim was to investigate whether two levels of caloric restriction (CR) in the early postweaning period can reverse obese phenotype in SL rats. The normal litter (NL) had 12 pups/dam and SL had 3 male pups/dam from the postnatal day 3 until day 21. After weaning, rats consumed lab chow as indicated: 1) NL and SL groups were on ad libitum regimen up to day 140, 2) another SL group was pair-fed (SL/PF) to NL(∼14% reduction), 3) SL/PF/AL group was pair-fed up to day 94 and then switched to ad libitum feeding, 4) SL/CR group received 24% reduction (moderate CR) in food intake compared with SL, and 5) SL/CR/AL group was on 24% CR up to day 94 and then switched to ad libitum feeding. Pair-feeding reduced body weight gains and serum insulin and leptin levels compared with SL rats, but these parameters were restored to SL levels in the SL/PF/AL rats after switching to ad libitum feeding. Interestingly, the moderate CR normalized these parameters in SL/CR and SL/CR/AL rats compared with NL. The expression of neuropeptide Y, proopiomelanocortin, and leptin receptor returned to control levels in hypothalami from SL/CR and SL/CR/AL rats. These results indicate that appropriate manipulation of energy intake during the early postweaning period could lead to longer-lasting effects on the regulation of body weight homeostasis via reversal of the early preweaning programming effects on the hypothalamic appetite regulation mechanism.
Hindbrain GLP-1 receptor-mediated suppression of food intake requires a PI3K-dependent decrease in phosphorylation of membrane-bound Akt
Authors: Rupprecht Laura E. , Mietlicki-Baase Elizabeth G. , Zimmer Derek J. , McGrath Lauren E. , Olivos Diana R. , Hayes Matthew R.
Published: July 2013

Glucagon-like peptide-1 (GLP-1) receptors (GLP-1R) expressed in the nucleus tractus solitarius (NTS) are physiologically required for the control of feeding. Recently, NTS GLP-1R-mediated suppression of feeding was shown to occur via a rapid PKA-induced suppression of AMPK and activation of MAPK signaling. Unknown are the additional intracellular signaling pathways that account for the long-term hypophagic effects of GLP-1R activation. Because cAMP/PKA activity can promote PI3K/PIP3-dependent translocation of Akt to the plasma membrane, we hypothesize that hindbrain GLP-1R-mediated control of feeding involves a PI3K-Akt-dependent pathway. Importantly, the novel evidence presented here challenges the dogmatic view that PI3K phosphorylation results in an obligatory activation of Akt and instead supports a growing body of literature showing that activation of cAMP/PKA can inhibit Akt phosphorylation at the plasma membrane. Behavioral data show that inhibition of hindbrain PI3K activity by a fourth icv administration of LY-294002 (3.07 μg) attenuated the food intake- and body weight-suppressive effects of a fourth icv administration of the GLP-1R agonist exendin-4 (0.3 μg) in rats. Hindbrain administration of triciribine (10 μg), an inhibitor of PIP3-dependent translocation of Akt to the cell membrane, also attenuated the intake-suppressive effects of a fourth icv injection of exendin-4. Immunoblot analyses of ex vivo NTS tissue lysates and in vitro GLP-1R-expressing neurons (GT1–7) support the behavioral findings and show that GLP-1R activation decreases phosphorylation of Akt in a time-dependent fashion. Current data reveal the requirement of PI3K activation, PIP3-dependent translocation of Akt to the plasma membrane, and suppression in phosphorylation of membrane-bound Akt to mediate the food intake-suppressive effects of hindbrain GLP-1R activation.
Mechanisms for food polyphenols to ameliorate insulin resistance and endothelial dysfunction: therapeutic implications for diabetes and its cardiovascular complications
Authors: Munir Kashif M. , Chandrasekaran Sruti , Gao Feng , Quon Michael J.
Published: July 2013

The rising epidemic of diabetes is a pressing issue in clinical medicine worldwide from both healthcare and economic perspectives. This is fueled by overwhelming increases in the incidence and prevalence of obesity. Obesity and diabetes are characterized by both insulin resistance and endothelial dysfunction that lead to substantial increases in cardiovascular morbidity and mortality. Reciprocal relationships between insulin resistance and endothelial dysfunction tightly link metabolic diseases including obesity and diabetes with their cardiovascular complications. Therefore, therapeutic approaches that target either insulin resistance or endothelial dysfunction alone are likely to simultaneously improve both metabolic and cardiovascular pathophysiology and disease outcomes. Moreover, combination therapies with agents targeting distinct mechanisms are likely to have additive or synergistic benefits. Conventional therapies for diabetes and its cardiovascular complications that are both safe and effective are insufficient to meet rising demand. Large, robust, epidemiologic studies demonstrate beneficial metabolic and cardiovascular health effects for many functional foods containing various polyphenols. However, precise molecular mechanisms of action for food polyphenols are largely unknown. Moreover, translation of these insights into effective clinical therapies has not been fully realized. Nevertheless, some functional foods are likely sources for safe and effective therapies and preventative strategies for metabolic diseases and their cardiovascular complications. In this review, we emphasize recent progress in elucidating molecular, cellular, and physiological actions of polyphenols from green tea (EGCG), cocoa (ECG), and citrus fruits (hesperedin) that are related to improving metabolic and cardiovascular pathophysiology. We also discuss a rigorous comprehensive approach to studying functional foods that is essential for developing novel, effective, and safe medications derived from functional foods that will complement existing conventional drugs.
Expression of the H19 Oncofetal Gene in Premalignant Lesions of Cervical Cancer: A Potential Targeting Approach for Development of Nonsurgical Treatment of High-Risk Lesions
Authors: Feigenberg Tomer , Gofrit Ofer N. , Pizov Galina , Hochberg Avraham , Benshushan Abraham
Published: July 2013

Background. Recent data suggest a role for H19 gene in promoting cancer transformation and progression. Cervical cancer, progresses from high-grade lesions (CIN3). At present, it is unclear if CIN lesions express H19. Objectives. To determine H19 expression in patient samples of CIN3 as well as the ability of a construct in which the promoter from the H19 gene drives expression of the diphtheria toxin A chain (DTA) to inhibit cervical cancer cell growth in vitro. Methods. H19 transcript levels were evaluated on 10 biopsies of CIN3 using in situ hybridization. PCR was used to examine H19 expression in cervical cancer cell lines and in two samples from a patient with cervical carcinoma. Cell lines were transfected with H19-DTA to determine its impact on cell number. Results. H19 gene was expressed in the area of CIN3 in 9 out of 10 samples. RT-PCR indicated expression of H19 in cervical cancer samples and in one of the three cell lines examined. Transfection of all cell lines with H19-DTA vector resulted in inhibited cell growth. Conclusions. H19 is expressed in the majority of CIN3 samples. These results suggest that most CIN3 lesions could be targeted by H19-DTA. Further in vivo preclinical studies are thus warranted.