bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Coronary Angiography Before Radiofrequency Ablation in Patients Presenting With Paroxysmal Supraventricular Tachycardia
Authors: Dorenkamp Marc , Zabel Markus , Sticherling Christian
Published: June 2007

During episodes of paroxysmal supraventricular tachycardia (PSVT), electrocardiograms frequently show ST-segment depressions, and patients may experience typical chest pain prompting invasive coronary angiography. We evaluated 114 patients presenting with PSVT for concomitant coronary artery disease (CAD). Patients were classified as to the type of PSVT, symptoms during PSVT, and cardiovascular risk factors. Maximum heart rate, extent of ST-segment depression, and cardiac troponin levels during PSVT were recorded. Patients were subjected to exercise testing and/or coronary angiography. During PSVT, symptoms suggestive of myocardial ischemia, including chest pain (31%), ST-segment depression (61%), and elevated troponin levels (12%), were common. Sixty-seven patients (59%) underwent coronary angiography. The overall prevalence of significant CAD was found to be low (4%) and did not correlate to symptoms during tachycardia. Routine coronary angiography cannot be recommended in patients with PSVT unless routine evaluation outside episodes of tachycardia suggests the presence of significant CAD.
Postconditioning Does Not Reduce Myocardial Infarct Size in an In Vivo Regional Ischemia Rodent Model
Authors: Dow Joan , Kloner Robert A.
Published: June 2007

In our laboratory, postconditioning reliably reduces lethal ventricular arrhythmias in an in vivo rat model but its effect on necrosis in our model is unknown. In the present analysis, we tested a variety of postconditioning regimens in anesthetized rats subjected to 45 minutes of coronary occlusion and 120 minutes of reperfusion or 30 minutes of coronary occlusion and 120 minutes of reperfusion. In all studies, area at risk was determined by the blue dye technique and area of necrosis was assessed with triphenyl tetrazolium chloride staining and computerized planimetry of ventricular slices. Postconditioning regimens included 4 cycles of 10 seconds of reperfusion/10 seconds of reocclusion, 4 cycles of 20 seconds of reperfusion/20 seconds of reocclusion, 8 cycles of 30 seconds of reperfusion/30 seconds of reocclusion, and 20 cycles of 10 seconds of reperfusion/10 seconds of reocclusion. Postconditioning did not reduce myocardial infarct size with any of these regimens.
The CHARM Program: Study Design Leads to Findings of Clinical and Public Health Importance
Authors: Hennekens Charles H. , Pfeffer Marc A. , Swedberg Karl
Published: June 2007

In large-scale randomized trials and their meta-analyses, beta-adrenergic blockers and angiotensin-converting enzyme inhibitors provide statistically significant and clinically important additive mortality and morbidity benefits in the treatment of heart failure. The CHARM trials were designed to test whether the angiotensin-receptor blocker candesartan would provide statistically significant and clinically important additive mortality and morbidity benefits to patients with heart failure as an alternative or in addition to angiotensin-converting enzyme inhibitors. CHARM demonstrated that an angiotensin-receptor blocker at a proven dose is an effective and safe therapy as an alternative or in addition to angiotensin-converting enzyme inhibitors in patients with heart failure, 55% of whom were receiving beta-adrenergic blockers. These benefits include reductions in cardiovascular mortality rate as well as in hospitalization for heart failure. Such patients have a 50% mortality rate at 5 years, and heart failure is the leading cause of hospitalization for patients 65 years of age and older.
Early Modern Anatomy and the Queen's Body Natural: The Sovereign Subject
Authors: Cregan Kate
Published: June 2007

In March 1603 the mortal remains of Queen Elizabeth I, against her stated wishes, were ‘opened’ to enable their temporary preservation until arrangements for her funeral could be completed. That post-mortem office was performed by members of the Worshipful Company of Barber-Surgeons of London, to whom her father had first granted a royal warrant to retrieve executed felons from the public gallows for their ‘better learning’ through lectures in anatomical dissection. In this article, portraiture of Elizabeth that appeals to the notion of her as an embodiment of the sovereign state of England is compared with a contemporary portrait of an anatomy lesson being performed by the Barber-Surgeons, drawing connections between the dissection of felons under sovereign law and the violability of the sovereign (female) body in the liminal period between her death and the delayed formalities of ascension for James I.
Indigeneity, media and cultural globalization
Authors: Glynn Kevin , Tyson A.F.
Published: June 2007

• This article analyzes Mataku, a New Zealand television anthology program created with an eye toward the global media market and, according to its producers, the first such TV drama ever to be `written, directed and produced entirely by Maori'. Mataku has emerged partly through the economic dynamics of globalization and partly as a consequence of government policies, institutional arrangements and funding mechanisms established in New Zealand in response to threats posed by neoliberalism. Mataku revisits traditional Maori narratives that have circulated orally for generations and repackages those stories within generic frameworks associated with the global resurgence of supernaturalism in television. The program therefore embodies aspects of both cultural globality and cultural hybridity on several levels. Its emphasis on the multiplicity of modalities through which `the old ways' assert their significance within contemporary life creates a space for complex postcolonial negotiations between past and present, disenchantment and alterity. •
Convergence culture in the creative industries
Authors: Deuze Mark
Published: June 2007

• This article maps the emerging practices in media professions like journalism, advertising, marketing communications and public relations in adapting to a new global environment, characterized by an increasingly participatory media culture. Among creatives and brand managers in ad agencies `interactive advertising' is at the center of the contemporary buzz. Marketers in the cultural industries brainstorm about the potential of upstream marketing, while in public relations the opportunities of two-way symmetrical communication are explored. Editors of news publications increasingly jump on the `citizen journalism' bandwagon. All these trends are part of the same phenomenon: a convergence of the cultures of media production and consumption. In this essay, these developments are discussed in terms of their potential impact on consensual assumptions about the nature of media work, seen through the lens of the combination of individual creativity and mass production, also known as creative industries. •
Self-evaluation and Ofsted Inspection
Authors: Plowright David
Published: June 2007

The Office for Standards in Education (Ofsted) is responsible for carrying out external inspections of all schools in England, in the UK. Compared with early inspections, there is now an increased focus on the contribution that school self-evaluation can make to the inspection process. However, it is clear from studies undertaken in recent years that there is a tension built into the inspection process: it is aimed at assuring accountability but also of ensuring development. The research reported here investigates how teaching staff and school managers in one case study school felt about the self-evaluation procedures that were put in place in preparation for its Ofsted inspection. The purpose is to develop an integrative model that brings together ideas about school self-evaluation, school improvement and the concept of the learning organization.
An Evaluation of Ofsted Reports on LEAs' Management of Attendance Issues
Authors: Reid Ken
Published: June 2007

This is the first article to analyse and evaluate Office for Standards in Education (Ofsted) reports on attendance issues within local authorities. A full cohort of Ofsted reports on local education authorities (LEAs) undertaken in 2003 in England were read, evaluated and used in the preparation of this article. The reports show that most LEAs face considerable scrutiny on attendance issues during the inspection process. The evidence also indicates that while there are some clear improvements in the management and administration of this agenda taking place, much more progress needs to be made within a number of LEAs. One in five LEAs received an `unsatisfactory' or `poor' grading for their management of attendance. These data also indicate that the inspectors now not only scrutinise overall attendance data and levels of authorized and unauthorized absence but also consider some of the reasons and the processes put in place to combat and reduce pupils' absenteeism. For example, they ascertain what individual LEAs are doing to improve attendance. How LEAs are managing this agenda is normally scrutinized in very considerable detail within the reports. The article summarizes both the positive features and major criticisms made by Ofsted during their visit to LEAs in 2003. All the signs are that Ofsted intends to tighten its scrutiny of attendance issues within LEA inspections using the recently revised procedures that will take account of the recommendations in the Children Act (2004).
creating a discourse of difference
Authors: Fisher Anne-Claire
Published: June 2007

Recent educational policy has attempted to alleviate glaring achievement gaps within increasingly diverse student groups in the USA. Despite these efforts districts not making yearly Adequate Yearly Progress (AYP) are predominantly in disenfranchised areas or may be serving very diverse students. This article showcases recent research, which has produced some significant results in closing achievement gaps within traditionally marginalized groups. Despite many years of research within the coexisting fields of inclusion, bilingual education, diversity and overrepresentation of minorities in special education, a cyclopic system unable to address the increasing diversity within our schools perseverates. This article will also investigate underlying ideologies that seem bent on defining micro-boundaries within differences, thereby continually redefining conditions for exclusion from a mythical homogeneous mass. Inclusion is seen as the unifying thread for an increasingly fragmented public education system. The process of coherence making is further illustrated and supported by theoreticians such as Clark, Dyson and Millward, and Fullan.
The Myc-evoked DNA damage response accounts for treatment resistance in primary lymphomas in vivo
Authors: Reimann Maurice , Loddenkemper Christoph , Rudolph Cornelia , Schildhauer Ines , Teichmann Bianca , Stein Harald , Schlegelberger Brigitte , Dörken Bernd , Schmitt Clemens A.
Published: June 2007

In addition to the ARF/p53 pathway, the DNA damage response (DDR) has been recognized as another oncogene-provoked anticancer barrier in early human tumorigenesis leading to apoptosis or cellular senescence. DDR mutations may promote tumor formation, but their impact on treatment outcome remains unclear. In this study, we generated ataxia telangiectasia mutated (Atm)–proficient and -deficient B-cell lymphomas in Eμ-myc transgenic mice to examine the role of DDR defects in lymphomagenesis and treatment sensitivity. Atm inactivation accelerated development of lymphomas, and their DNA damage checkpoint defects were virtually indistinguishable from those observed in Atm+/+-derived lymphomas that spontaneously inactivated the proapoptotic Atm/p53 cascade in response to Myc-evoked reactive oxygen species (ROS). Importantly, acquisition of DDR defects, but not selection against the ARF pathway, could be prevented by lifelong exposure to the ROS scavenger N-acetylcysteine (NAC) in vivo. Following anticancer therapy, DDR-compromised lymphomas displayed apoptotic but, surprisingly, no senescence defects and achieved a much poorer long-term outcome when compared with DDR-competent lymphomas treated in vivo. Hence, Atm eliminates preneoplastic lesions by converting oncogenic signaling into apoptosis, and selection against an Atm-dependent response promotes formation of lymphomas with predetermined treatment insensitivity.
Novel landmark-guided routes in ants
Authors: Collett T. S. , Graham P. , Harris R. A.
Published: June 2007

We review studies in which ants familiar with fixed routes between their nest and a feeding site are displaced from one of these destinations to an unfamiliar site away from the route. Ants can reach their goal from such novel release sites guided by distant landmarks. We suggest that an ant's ability to take such novel landmark-guided routes after displacement is a by-product of the robustness of normal route-following and is unlikely to reflect the ant's use of a map-like knowledge of its surroundings.
Kinematics, hydrodynamics and energetic advantages of burst-and-coast swimming of koi carps (Cyprinus carpio koi)
Authors: Wu Guanhao , Yang Yan , Zeng Lijiang
Published: June 2007

Koi carps frequently swim in burst-and-coast style, which consists of a burst phase and a coast phase. We quantify the swimming kinematics and the flow patterns generated by the carps in burst-and-coast swimming. In the burst phase, the carps burst in two modes: in the first, the tail beats for at least one cycle (multiple tail-beat mode); in the second, the tail beats for only a half-cycle (half tail-beat mode). The carp generates a vortex ring in each half-cycle beat. The vortex rings generated during bursting in multiple tail-beat mode form a linked chain, but only one vortex ring is generated in half tail-beat mode. The wake morphologies, such as momentum angle and jet angle, also show much difference between the two modes. In the burst phase,the kinematic data and the impulse obtained from the wake are linked to obtain the drag coefficient (Cd,burst≈0.242). In the coast phase, drag coefficient (Cd,coast≈0.060) is estimated from swimming speed deceleration. Our estimation suggests that nearly 45% of energy is saved when burst-and-coast swimming is used by the koi carps compared with steady swimming at the same mean speed.
Behavioral context-dependent modulation of descending statocyst pathways during free walking, as revealed by optical telemetry in crayfish
Authors: Hama N. , Tsuchida Y. , Takahata M.
Published: June 2007

Crustacean posture control is based on a complex interaction between the statocyst input and other sensory inputs as well as the animal's behavioral context. We examined the effects of behavioral condition on the activity of descending statocyst pathways using an optical telemetry system that allowed underwater recording of neuronal signals from freely behaving crayfish. A functionally identified statocyst-driven interneuron that directionally responded to body tilting without a footboard and to tilting of the footboard was found to show complicated responses depending upon the ongoing behavior of the animal when it freely walked around in water on the aquarium floor. The spike firing frequency of the interneuron increased significantly during walking. When the animal stood or walked on the tilted floor, the interneuron activity represented the tilt angle and direction if the abdomen was actively flexed, but not if it was extended. Two other statocyst-driven descending interneurons were found to be affected differently by the animal's behavioral condition: the spike activity of one interneuron increased during walking, but its directional response on the tilted floor was completely absent during abdominal posture movements, whereas that of another interneuron was enhanced during abdominal extension only, representing the tilt angle and direction. The results obtained in this study provide the first experimental demonstration that crustacean postural control under natural conditions is dependent on very fine aspects of the animal's locomotor behavioral context,suggesting far more complex control mechanisms than those expected from the experimental data obtained in isolated and fixed animals.
Effects of medullary Raphé stimulation on fictive lung ventilation during development in Rana catesbeiana
Authors: Belzile Olivier , Gulemetova Roumiana , Kinkead Richard
Published: June 2007

To better understand serotonergic modulation of air breathing during bullfrog development, we measured changes in fictive lung ventilation frequency associated with focal stimulation of the rostral region of the medullary Raphé neurons. Electrical (3 to 33 Hz) and chemical(glutamate microinjections; 0.5 mol l–1, 0.3–10 nl)activation of Raphé neurons was performed in brainstem preparations from three developmental stages (pre- and metamorphic tadpoles and adult frogs). Fictive lung ventilation was recorded extracelluarly from the Vth and Xth cranial nerves. Electrical stimulation of Raphé neurons caused a frequency-dependent increase in lung burst frequency in pre-metamorphic tadpoles only. In metamorphic tadpoles, an increase in fictive lung ventilation was observed at 20 Hz only. Electrical stimulation had no effect in preparations from adult frogs. Glutamate microinjections elicited similar responses as a lung burst frequency increase was observed in the pre-metamorphic group only. Regardless of the stimulation technique used, the increase in fictive lung ventilation was attenuated by the selective 5-HT3 antagonist tropisetron (5–20 μmol l–1). Results from immunohistochemical analysis of the Raphé region stimulated do not correlate with functional data as the number of 5-HT immunoreactive neurons within this region increases during development. We conclude that, in this preparation, stimulation of lung ventilation by the medullary Raphé is restricted to early(pre-metamorphic) stages.
Effect of osmotic shrinkage and hormones on the expression of Na+/H+ exchanger-1,Na+/K+/2Cl– cotransporter and Na+/K+-ATPase in gill pavement cells of freshwater adapted Japanese eel,Anguilla japonica
Authors: Tse William K. F. , Au Doris W. T. , Wong Chris K. C.
Published: June 2007

It is well-known that gill epithelial cells are important in fish osmoregulation. However, studies on the effect of osmotic stress on the direct cellular responses of the gill epithelial cells are limited. In this paper, we aimed to determine the effects of osmotic hypertonicity, hormones and cellular signaling molecules on the expression of ion transporters in the cultured primary freshwater pavement cells (PVCs), prepared from freshwater-adapted eels (Anguilla japonica). Our data demonstrated that the hypertonic(500 mOsmol l–1) treatment of the isolated PVCs induced cell shrinkage, followed by regulatory volume increase (RVI). Application of blockers (i.e. ouabain, bumetanide and EIPA) demonstrated that Na+/K+-ATPase,Na+/K+/2Cl– cotransporter (NKCC) and Na+/H+ exchanger-1 (NHE-1) were involved in RVI. Western blot analysis of the hypertonic-treated cells revealed a significant induction of NHE-1, NKCC and, α and β subunits of Na+/K+-ATPase. In nonshrunken cultured PVCs, we found that dexamethasone and dibutyryl cAMP treatments significantly stimulated the expression levels of the three ion transporters. Both prolactin and insulin-like growth factor-1, can only induce the expression of NKCC. The effect of thyroid hormone (T3) and dibutyryl cGMP was negligible. In this study, the induction of ion transporter expression was found to be post-transcriptionally regulated as no significant change in mRNA levels was detected. This observation implies that the regulation is rapid and is probably induced via nongenomic actions.
Gill-specific transcriptional regulation of Na+/K+-ATPase α-subunit in the euryhaline shore crabPachygrapsus marmoratus: sequence variants and promoter structure
Authors: Jayasundara Nishad , Towle David W. , Weihrauch Dirk , Spanings-Pierrot Céline
Published: June 2007

The sodium pump (Na+/K+-ATPase) has been implicated in osmoregulatory ion transport in many aquatic animals. In the euryhaline hyper–hypoosmoregulating shore crab Pachygrapsus marmoratus,induction of Na+/K+-ATPase α-subunit mRNA varies between gills in response to osmotic stress. Following transfer of crabs from normal seawater (36‰ salinity) to diluted seawater (10‰), a condition in which gills exhibit net ion uptake, α-subunit mRNA expression is upregulated in all tested gills, albeit with differing time courses. By contrast, following transfer from seawater to hypertonic(45‰) seawater, a condition in which the animal is excreting ions,α-subunit mRNA is induced primarily in gill no. 7 (nine in total),suggesting that this gill may be associated specifically with ion excretion in P. marmoratus.

Full-length sequencing of α-subunit cDNA revealed the existence of two isoforms differing only in the inclusion of an 81-nucleotide segment within the N-terminal open reading frame of the long (D) form in comparison to the short (C) form. The 81-nucleotide segment encodes a 14-3-3 protein binding site that may facilitate movement of the α-subunit protein between intracellular compartments and the plasma membrane. mRNA expression of the two forms followed similar patterns upon salinity transfer. Genomic DNA sequencing of the putative promoter region of the α-subunit gene demonstrated a spectrum of predicted transcription factor binding sites that are likely associated with the complex expression pattern observed among gills following osmotic stress.
Effects of ship noise on the detectability of communication signals in the Lusitanian toadfish
Authors: Vasconcelos Raquel O. , Amorim M. Clara P. , Ladich Friedrich
Published: June 2007

Underwater noise pollution is an increasing environmental problem which might affect communication, behaviour, fitness and consequently species'survival. The most common anthropogenic noises in aquatic habitats derive from shipping. In the present study we investigated the implications of noise pollution from a ship on the sound detectability, namely of conspecific vocalizations in the Lusitanian toadfish, Halobatrachus didactylus. Ambient and ferry-boat noises were recorded in the Tagus River estuary(Portugal), as well as toadfish sounds, and their sound pressure levels determined. Hearing sensitivities were measured under quiet lab conditions and in the presence of these masking noises at levels encountered in the field,using the auditory evoked potentials (AEP) recording technique. The Lusitanian toadfish is a hearing generalist, with best hearing sensitivity at low frequencies between 50 and 200 Hz (below 100 dB re. 1 μPa). Under ambient noise conditions, hearing was only slightly masked at lower frequencies. In the presence of ship noise, auditory thresholds increased considerably, by up to 36 dB, at most frequencies tested. This is mainly because the main energies of ferry-boat noise were within the most sensitive hearing range of this species. Comparisons between masked audiograms and sound spectra of the toadfish's mating and agonistic vocalizations revealed that ship noise decreased the ability to detect conspecific acoustic signals. This study provides the first evidence that fishes' auditory sensitivity can be impaired by ship noise and that acoustic communication, which is essential during agonistic encounters and mate attraction, might be restricted in coastal environments altered by human activity.
The role of metals in molluscan adhesive gels
Authors: Werneke S. W. , Swann C. , Farquharson L. A. , Hamilton K. S. , Smith A. M.
Published: June 2007

Several gastropod molluscs produce glues that are interesting because they are dilute gels and yet they produce strong adhesion. Specific glue proteins have been identified that play a central role in this adhesion, possibly by crosslinking other polymers in the gel. This study investigates the role of metals in the action of these glue proteins. Atomic absorption spectrometry showed that glue from the slug Arion subfuscus contains substantial quantities of zinc (46±7 p.p.m. and 189±80 p.p.m. in two different sets of experiments) and also iron, copper and manganese (2–7 p.p.m.). Iron-specific staining demonstrates that iron is bound specifically to the 15 kDa glue protein. Several approaches were used to show that these metals have important functional effects. Adding iron or copper to dissolved glue causes the proteins to precipitate rapidly, although zinc has no effect. Removing iron and related transition metals with a chelator during secretion of the glue causes a sixfold increase in the solubility of the glue. Once the glue has set, however, removing these metals has no effect. Finally, the gel-stiffening activity of the glue proteins was measured in the presence and absence of the chelator. The chelator eliminated the gel-stiffening effect of the proteins, suggesting that transition metals were necessary for the proteins to act on the gel. Thus, the glue contains transition metals and these metals play an essential role in glue function.
The application of an exhaust heat exchanger to protect the catalyst and improve the fuel economy in a spark-ignition engine
Authors: Lee Seokhwan , Bae Choongsik
Published: June 2007

A close-coupled catalyst (CCC) can reduce engine cold-start emissions by utilizing the energy in the exhaust gas. However, in case the engine is operated at high engine speed and load condition, the catalytic converter may be damaged and eventually deactivated by thermal ageing. Excess fuel is sometimes supplied intentionally to lower the exhaust gas temperature, avoiding thermal ageing. This sacrifices fuel economy and exhaust emissions.

This paper describes the results of an exhaust heat exchanger to lower the exhaust gas temperature, mainly under high load conditions. The heat exchanger was installed between the exhaust manifold and the inlet of the CCC to avoid thermal ageing. The exhaust heat exchanger successfully decreased the exhaust gas temperature, which eliminated the requirement of fuel enrichment under high-load conditions. A reduction of fuel consumption by approximately 7.7 per cent at high vehicle speed was achieved due to no fuel enrichment. Although the amount of hydrocarbon during the cold start increases due to the increment of the catalyst light-off time, it still meets the EURO-IV regulations. This problem could be resolved by adopting the solenoid valve to cut off the coolant at the inlet of the coolant passage of the heat exchanger.
Effect of additives on ignition of methane at homogeneous charge compression ignition engine-like conditions
Authors: Morsy M H , Chung S H
Published: June 2007

The influence of additives including dimethyl ether (DME), formaldehyde (CH2O), and hydrogen peroxide (H2O2) for the control of ignition of methane fuel in HCCI engines has been investigated numerically. The chemical kinetic mechanisms incorporated GRI-Mech 3.0 which considers 53 species and 325 reactions together with the DME reaction scheme consisting of 79 species and 351 reactions. Computations were carried out in a constant-volume bomb at engine-like conditions to assess the ignition delay times with the additives at various initial temperatures, pressures, equivalence ratios, and compositions. Comparison between the two kinetic mechanisms was first carried out to examine the validity using available experimental data. Reasonable agreement was observed between the simulation and experiment. The effect of H2O2 addition in reducing the ignition delay time was most pronounced in comparison with the other two additives DME and CH2O for all conditions examined. Sensitivity analyses were performed to identify important reactions in reducing ignition delays. The present study demonstrated the possibility of controlling and improving the ignition characteristics of natural gas homogeneous charge compression ignition engines by means of the additives.
Lubrication regime of the contact between fat and bone in bovine tissue
Authors: Theobald P , Byrne C , Oldfield S F , Dowson D , Benjamin M , Dent C , Pugh N , Nokes L D M
Published: June 2007

Fat pads are masses of encapsulated adipose tissue located throughout the human body. Whilst a number of studies describe these soft tissues anatomically little is known about their biomechanics, and surgeons may excise them arthroscopically if they hinder visual inspection of the joint or bursa. By measuring the coefficient of friction between, and performing Sommerfeld analysis of, the surfaces approximating the in vivo conjuncture, this contact has been shown to have a coefficient of friction of the order of 0.01. The system appears to be lubricated hydrodynamically, thus possibly promoting low levels of wear. It is suggested that one of the functions of fat pads associated with subtendinous bursae and synovial joints is to generate a hydrodynamic lubricating layer between the opposing surfaces.
Three-dimensional finite element model of the two-layered oesophagus, including the effects of residual strains and buckling of mucosa
Authors: Yang W , Fung T C , Chian K S , Chong C K
Published: June 2007

This study was carried out to develop a two-layered finite element model of the oesophagus. The outer muscle and inner mucosal layer were constructed individually with different mechanical properties and zero-stress opening angles. With the model, two simulations were performed. First, the distention of oesophageal wall under the pressurized state was investigated, from which the effects of residual strains on the stress distribution were evaluated. Second, the buckling modes were determined using a linear eigenvalue analysis. The self-contact capability in ABAQUS was applied to simulate the folding of mucosa under the muscle contraction. The first simulation indicated that, by taking the residual strains into account, the mucosa undertook a very small portion of stress and the luminal pressure almost transmitted completely to the outer muscle layer. On the other hand, the folding of mucosa was shown to be able to reduce the contractile force of circular muscle to maintain the lumen closure. In conclusion, the preliminary study demonstrated the feasibility of simulating the oesophageal peristaltic transport using finite element analysis.
Maspin Is Involved in Bone Matrix Maturation by Enhancing the Accumulation of Latent TGF-β
Authors: Tokuyama Reiko , Satomura Kazuhito , Maeda Eriko , Kudoh Keiko , Yamasaki Yasuhumi , Nagayama Masaru
Published: June 2007

Maspin, a serine protease inhibitor, is expressed by formative osteoblasts. The repression of maspin expression in osteoblastic cells decreased the level of latent TGF-β in the extracellular matrix, whereas the overexpression of maspin increased latent TGF-β. These findings suggest that maspin plays an important role in bone matrix formation, particularly in the accumulation of latent TGF-β.

Introduction: Maspin is a serine protease inhibitor that exhibits tumor suppressive and anti-angiogenic activities. This study was performed to elucidate a possible role for maspin in bone formation.

Materials and Methods: We performed immunohistochemical analysis of the expression of maspin during endochondral ossification. We evaluated the expression of maspin mRNA and protein in ROS 17/2.8 cells and primary rat osteoblastic cells by RT-PCR, immunocytochemistry, and Western blot analysis. We also examined the accumulation of TGF-β in the extracellular matrix of cultured ROS 17/2.8 cells after transfection with vectors expressing either maspin or maspin antisense.

Results: We observed expression of maspin by active osteoblasts in vivo. Rat osteoblastic cells also expressed maspin mRNA and protein in vitro. Moreover, the accumulation of latent TGF-β in the extracellular matrix significantly decreased in cultures exposed to an anti-maspin antibody and when cells were transfected with a maspin antisense-expressing vector. In contrast, accumulation of latent TGF-β in the extracellular matrix increased after transfection of cells with a vector expressing maspin.

Conclusions: These findings suggest that maspin expressed in active osteoblasts plays an important physiological role during maturation of the bone matrix, and in particular, during the process of accumulation of latent TGF-β in the extracellular matrix.
Factors Associated with Contraceptive Use and Nonuse, United States, 2004
Authors: Frost Jennifer J. , Singh Susheela , Finer Lawrence B.
Published: June 2007

CONTEXT:  Each year, nearly one in four U.S. women at risk of unintended pregnancy experience one or more months of contraceptive nonuse. Understanding what factors are associated with risky contraceptive use patterns can inform programs and policies designed to reduce levels of unintended pregnancy.

METHODS:  A nationally representative sample of 1,978 adult women at risk for unintended pregnancy was surveyed over the telephone in 2004. Respondents provided information on contraceptive use over the past 12 months. Multiple logistic regressions were used to identify factors associated with different contraceptive use patterns.

RESULTS:  Ambivalence about avoiding pregnancy was strongly associated with both contraceptive nonuse and having a gap in use while remaining at risk of unintended pregnancy (odds ratios, 2.4 and 2.0, respectively). Other significant predictors of either of these risky contraceptive behaviors were having less than a college education, being black, being 35–44 years old, having infrequent sexual intercourse, not being in a current relationship, being dissatisfied with one’s method and believing that contraceptive service providers were not available to answer method‐related questions (1.7–3.8).

CONCLUSIONS:  Providers could better help women avoid unintended pregnancy by initiating regular assessments of method use difficulties, improving counseling on method choice and pregnancy risk, and identifying and assisting women at higher risk for inconsistent method use because of disadvantage, relationship characteristics or ambivalence about pregnancy prevention. In addition to providers’ efforts, broader societal commitment is critical for increasing contraceptive knowledge and expanding access to contraceptive care for all women who are at risk of having an unintended pregnancy.
The effect of pressure on leakage in water distribution systems
Authors: van Zyl J. E. , Clayton C. R. I.
Published: June 2007

The results of pressure management field studies have shown that the leakage exponent is often considerably higher than the theoretical orifice value of 0·5. The purpose of this paper is to identify and analyse factors that may be responsible for the higher leakage exponents. Four factors are considered: leak hydraulics, pipe material behaviour, soil hydraulics and water demand. It is concluded that a significant proportion of background leakage can consist of transitional flow, and thus have a leakage coefficient value above 0·5 (although not above 1). An important factor is pipe material behaviour: laboratory test results are presented to show that pipe material behaviour can explain the range of leakage exponents observed in the field. The complexity of the interaction between a leaking pipe and its surrounding soil is discussed and it is concluded that the relationship between pressure and leakage is unlikely to be linear. Finally, it is noted that if water demands are present in minimum night flows, the resulting leakage exponent is probably underestimating the true value.
Optimising water supply and distribution operations
Authors: Rao Z. F. , Wicks J. , West S.
Published: June 2007

This paper presents an adaptive optimisation system for dynamic operational control of water supply and distribution networks. Based on the combined use of an artificial neural network for predicting the consequences of different pumps and valve settings and a genetic algorithm for optimisation, the energy cost minimisation system (ENCOMS) is designed to assist water distribution system operators to select optimal operating control settings that will best meet not only the current demands but also the projected ones. ENCOMS identifies maximum cost savings by taking into account the electricity tariff and other system operational constraints that prescribe lower and upper limits on nodal pressures and service reservoirs storages, alternative supply sources and so on. The real-time control process operates continually and is updated at short intervals by data transmitted from the SCADA system and the updated demand forecast. The control system is generic in the sense that it can be applied to any distribution network. It is customised for each application to ensure optimal performance. It is extremely powerful and flexible so that the peculiarities of the specific network and/or tariff structure can be accommodated, as well as the preferences of the operator with regard to the time interval between updates, the operating horizon and so on. Multiple sources of treated water with different production costs can also be incorporated, as can various pressure zones and demand districts.
Monosomy 7 with severe myelodysplasia developing during imatinib treatment of Philadelphia‐positive chronic myeloid leukemia: Two cases with a different outcome
Authors: Navarro José‐Tomás , Feliu Evarist , Grau Javier , Espinet Blanca , Colomer Dolors , Ribera Josep‐Maria , Oriol Albert , Granada Isabel , Juncà Jordi , Millá Fuensanta
Published: June 2007

Chromosomal abnormalities in Ph‐negative metaphases from patients with chronic myeloid leukemia (CML) treated with imatinib have been described in some cases. Trisomy 8 is the most frequent, but monosomy 7 has also been described. However, the association of these chromosomal alterations with myelodysplasia has been scarcely reported. We report the appearance of monosomy 7 in Ph‐negative cells, associated with severe dysplasia, in two patients with CML treated with imatinib, with a different outcome: one with a transient evolution and the other evolving to acute myeloid leukemia. Am. J. Hematol., 2007. © 2007 Wiley‐Liss, Inc.
Synthesis and characterization of novel star polymer with β‐cyclodextrin core and its metal complexes
Authors: Jiang Yan , Zhang Hongwen , Du Lianxiang , Zhang Kai , Wang Jingyuan
Published: June 2007

A novel star polymer with β‐cyclodextrin (β‐CD) core and polyacrylonitrile arms and its metal complexes (Cu2+, Zn2+, and Ag+) were synthesized and characterized by means of infrared spectra, ultraviolet, GPC, X‐ray photoelectron spectroscopy, differential scanning calorimetry, cyclic voltammetry, and electron spin resonance. The results indicate that the monomers of acrylonitrile were initiated by functionalized β‐CD. The thermal properties of star polymer were improved greatly after transitional metal ions were introduced into it. The novel star polymer metal complexes possess properties of metal ions, polymer, and β‐CD. Furthermore, it shows stable electrochemical activity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Characterization of liquefied wood residues from different liquefaction conditions
Authors: Pan Hui , Shupe Todd F. , Hse Chung‐Yun
Published: June 2007

The amount of wood residue is used as a measurement of the extent of wood liquefaction. Characterization of the residue from wood liquefaction provides a new approach to understand some fundamental aspects of the liquefaction reaction. Residues were characterized by wet chemical analyses, Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), and scanning electron microscopy (SEM). The Klason lignin content of the residues decreased, while the holocellulose and α‐cellulose contents increased as the phenol to wood ratio (P/W) increased. A peak at 1735 cm−1, which was attributed to the ester carbonyl group in xylan, disappeared in the FTIR spectra of the residues from liquefied wood under a sealed reaction system, indicating significantly different effects of atmospheric versus sealed liquefaction. The crystallinity index of the residues was higher than that of the untreated wood particles and slightly increased with an increase in the P/W ratio. The SEM images of the residues showed that the fiber bundles were reduced to small‐sized bundles or even single fibers as the P/W ratio increased from 1/1 to 3/1, which indicated that the lignin in the middle lamella had been dissolved prior to the cellulose during liquefaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Synthesis of monomethoxy poly(ethylene glycol) without diol poly(ethylene glycol)
Authors: Zhang Jing , Zhao Yong‐Jiang , Su Zhi‐Guo , Ma Guang‐Hui
Published: June 2007

Since monomethoxy poly(ethylene glycol) (mPEG) inevitably contains diol PEG and is difficult to get high molecular weight through traditional synthesis at high temperature under high pressure, a novel synthetic technique via anionic solution polymerization was reported in this study. With a new initiating system, potassium naphthalene and methanol, was introduced, the polymerization proceeded at ambient temperature and side reactions were well restrained. Furthermore, a slight excess of potassium naphthalene can effectively remove the trace of water and oxygen in the reaction system. Under this condition, mPEG was nearly quantitatively obtained without containing diol PEG. Its Mn ranged from 1 to 30 kDa and the polydispersity was kept lower than 1.07. Characterization of the mPEG obtained was carried out using GPC to determine the content of diol PEG and 1H‐NMR and MALDI‐ToF MS spectroscopic analysis to confirm the exact structure. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Curing and thermal behavior of DGEBA in presence of dianhydrides and aromatic diamine
Authors: Jain Ritu , Choudhary Veena , Narula A. K.
Published: June 2007

The article describes the curing behavior of diglycidyl ether of bisphenol‐A using benzophenone 3,3′, 4,4′‐tetracarboxylic acid dianhydride (BTDA)/naphthalene 1,4,5,8‐tetracarboxylic dianhydride (NTDA)/or mixture of BTDA and 4,4′‐ diaminodiphenyl sulfone (DDS)/ or NTDA and DDS in varying molar ratio as curing agent. Differential scanning calorimetry was used to investigate the cure kinetics by recording DSC scans at heating rates of 5, 10, 15, and 20 °C/min. The peak exotherm temperature was found to be dependent on the heating rate, structure of the dianhydride as well as on the DDS/dianhydride molar ratio. Activation energy of curing reaction as determined in accordance to Ozawa's method was found to be dependent on the structure of anhydride as well as on the ratio of anhydride to amine. Thermal stability of the isothermally cured resins was evaluated using dynamic thermogravimetry in nitrogen atmosphere. The char yield was highest in case of resins cured using DDS/BTDA mixture or DDS/NTDA one (0.75 : 0.25; sample EB‐1/or EN‐1). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Reswelling transition of poly(sodium acrylate) gels due to destruction of hydrogen bonds observed by ATR FTIR spectroscopy
Authors: Sato Hiroaki , Hirashima Yumiko , Suzuki Atsushi
Published: June 2007

We report the reswelling transition of a physically crosslinked polyelectrolyte hydrogel in water, which was prepared using poly(sodium acrylate) as the main constituent and Al ions as the crosslinker. The nonmonotonic swelling behavior was observed at room temperature (25°C) under the continuous exchange of water; an as‐prepared gel swelled at the first stage (the swelling process) and then shrunk very slowly at the second stage (deswelling process). In the deswelling process, the water exchange was stopped and the diameter of the gel in a limited amount of water was measured as a function of the temperature. The gels reswelled at different transition temperatures in the heating processes, which depended on the initial diameter at 25°C (resulting from the different numbers of water exchange). The reswollen state was stable at 25°C and could shrink again as a result of successive water exchanges at 25°C. In the following temperature increase in the closed system, the reswelling phenomenon was observed again. The destruction of the hydrogen bonds introduced by the water exchange was confirmed by the attenuated total refraction Fourier transform infrared measurements. The reversible transition behavior between the deswollen and the reswollen states is discussed in terms of the formation and destruction of the hydrogen bonds. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Effect on properties of regenerated silk fibroin fiber coagulated with aqueous methanol/ethanol
Authors: Zuo Baoqi , Liu Leigen , Wu Zhengyu
Published: June 2007

Random coil silk fibroin membrane was designed to dissolve with HFIP, and regenerated silk fibroin fibers were obtained by wet spinning. The effect of coagulants (methanol and ethanol) on structure, mechanical properties, and actinomyces biodegradability of regenerated silk fibroin fiber was investigated through X‐ray diffraction, IR spectra, and TGA. The results showed that the effect on the structure and properties of regenerated silk fibroin fibers coagulated by methanol and ethanol was negligible, but the difference in actinomyces biodegradability in vitro was obvious. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Morphology, deformation behavior and thermomechanical properties of polypropylene/maleic anhydride grafted polypropylene/layered silicate nanocomposites
Authors: Dubnikova I. L. , Berezina S. M. , Korolev Yu. M. , Kim G.‐M. , Lomakin S. M.
Published: June 2007

Nanocomposites polypropylene (PP) with 3 and 7 wt % of clay were prepared by melt mixing. Four types of maleic anhydride grafted PP (MAPP) in broad range of MA groups content (0.3–4 wt %) and molecular weights (MW) were used as polar compatibilizers. The effect of the MAPP kind on both the clay dispersion and miscibility with PP was studied. The mixed intercalated/exfoliated morphologies of nanocomposites in the presence of all studied compatibilizers were revealed by XRD and TEM. The oligomer compatibilizer with 4 wt % of MA groups increases the intercalation ability of polymer into clay galleries but this one has limited miscibility with PP and worsens crystalline structure of polymer matrix. The MAPPs with 0.3–1.3% of MA are characterized by the lower intercalation ability but well cocrystallize with PP. Maximum reinforcing effect is attained using high MW MAPP with 0.6% MA and for nanocomposite with 7 wt % (3.8 vol %) of clay it averages almost 1.7 times relative to neat PP and 1.3 times relative to noncompatibilized composite. Dynamic storage moduli of nanocomposites compatibilized by MAPPs with 0.3–1.3% of MA containing 7 wt % of clay increase up to 1.4–1.5 around 30–75°C and over the whole temperature range remain higher compared with both neat PP and uncompatibilized composite. On the contrary, the oligomer MAPP with 4 wt % of MA groups decreases the thermal–mechanical stability of nanocomposite at high temperature compared with both PP and uncompatibilized composites. The study of nanocomposites flammability showed that creating complex composites containing both layered silicate and relatively small amount of magnesium hydroxide can be a successful approach to reduce the combustibility of PP‐based nanocomposites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007