bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic sources for context-free languages
Authors: Hutchins Sandra E.
Published: June 2007

The concept of a stochastic source of a context-free language is presented and one possible source model based on a probabilistic grammar is defined. It is shown that this source is equivalent to an infinite Markov chain which can be defined recursively. Various statistics of the Markov chain are derived.

An analogue of the Greibach Normal Form theorem is presented, which then allows for the construction of a Markov source with a single terminal symbol per transition. The class of probability distributions generable over context-free languages by such sources is examined.
Laboratory exercises in online information assurance courses
Authors: Bhagyavati
Published: June 2007

Information assurance courses delivered in an online environment pose challenges to the development of meaningful hands-on exercises for students. This article presents techniques on furnishing laboratory exercises to online students and presents examples of assignments drawn from the author's experiences in teaching online courses for over three years. These assignments have proven successful in enhancing the learning experiences of undergraduate and graduate computer science students in introductory and advanced courses in the area of information assurance. Typical courses include introduction to computer networks, computer and network security, information assurance, network management, wireless networks and applications, computer forensics, and risk assessment.
Laboratory experiments for network security instruction
Authors: Brustoloni José Carlos
Published: June 2007

We describe a sequence of five experiments on network security that cast students successively in the roles of computer user, programmer, and system administrator. Unlike experiments described in several previous papers, these experiments avoid placing students in the role of attacker. Each experiment starts with an in-class demonstration of an attack by the instructor. Students then learn how to use open-source defense tools appropriate for the role they are playing and the attack at hand. Threats covered include eavesdropping, dictionary, man-in-the-middle, port scanning, and fingerprinting attacks. Defense skills gained by students include how to forward ports with OpenSSH, how to prevent weak passwords with CrackLib, how to salt passwords, how to set up a simple certifying authority, issue and verify certificates, and guarantee communication confidentiality and integrity using OpenSSL, and how to set up firewalls and IPsec-based virtual private networks. At two separate offerings, tests taken before and after each experiment showed that each has a statistically significant and large effect on students' learning. Moreover, surveys show that students finish the sequence of experiments with high interest in further studies and work in the area of security. These results suggest that the experiments are well-suited for introductory security or networking courses.
Measurement of Reaching Kinematics and Prehensile Dexterity in Nonhuman Primates
Authors: Pizzimenti Marc A. , Darling Warren G. , Rotella Diane L. , McNeal David W. , Herrick James L. , Ge Jizhi , Stilwell-Morecraft Kimberly S. , Morecraft Robert J.
Published: June 2007

A modified “Klüver” or dexterity board was developed to assess fine control of hand and digit movements by nonhuman primates during the acquisition of small food pellets from wells of different diameter. The primary advantages of the new device over those used previously include standardized positioning of target food pellets and controlled testing of each hand without the need for restraints, thereby allowing the monkey to move freely about the cage. Three-dimensional video analysis of hand motion was used to provide measures of reaching accuracy and grip aperture, as well as temporal measures of reach duration and food-pellet manipulation. We also present a validated performance score based on these measures, which serves as an indicator of successful food-pellet retrieval. Tests in three monkeys show that the performance score is an effective measure with which to study fine motor control associated with learning and handedness. We also show that the device and performance scores are effective for differentiating the effects of localized injury to motor areas of the cerebral cortex.
Studying the visual system in awake monkeys: two classic papers by Robert H. Wurtz
Authors: Goldberg Michael E.
Published: June 2007

This essay looks at the historical significance of two APS classic papers that are freely available online:

Wurtz RH.

Visual receptive fields of striate cortex neurons in awake monkeys. J Neurophysiol 32: 727–742, 1969 ( http://jn.physiology.org/cgi/reprint/32/5/727 ).

Wurtz RH.

Comparison of effects of eye movements and stimulus movements on striate cortex neurons of the monkey. J Neurophysiol 32: 987–994, 1969 ( http://jn.physiology.org/cgi/reprint/32/6/987 ).
Gene expression analysis illuminates the transcriptional programs underlying the functional activity of ex vivo-expanded granulocytes
Authors: Huang Li Ting , Paredes Carlos J. , Papoutsakis Eleftherios T. , Miller William M.
Published: June 2007

Global gene expression analysis established the temporal expression patterns and programs underlying the development of functional activity of ex vivo-expanded (EXE) human granulocytes, as well as differences compared with peripheral blood (PB) granulocytes. CD34+progenitor cells were cultured for 3 wk to induce rapid expansion and granulocytic differentiation, with 40% CD15+cells by day 3 and 90% by day 12. Phagocytic and respiratory burst activity increased with the fraction of CD15++CD11b+cells (myelocytes to segmented) and peaked by day 17. However, only 25% of CD15++CD11b+cells were phagocytic, and respiratory burst activity was one-third that of PB granulocytes. EXE granulocytes from later days and PB granulocytes showed similar expression of Fcγ receptors (-1A, -2A, -2C, -3A) and complement receptors (-1, -3, -4). Later downregulation of CD36 (expressed by macrophages) suggests lineage plasticity early in granulocytic differentiation. Expression in mature EXE and PB granulocytes was similar for most Fcγ receptor-mediated phagocytosis signaling proteins, including high-level expression of Hck, Fgr, and the actin-related protein 2/3 complex. Lower expression of Lyn, Cdc42, pleckstrin, and PKCβIby EXE granulocytes may explain decreased phagocytosis. PB and mature EXE granulocytes expressed similar levels of NADPH oxidase complex genes and receptors for fMLP-mediated respiratory burst. Lower burst activity by EXE granulocytes may result from lower expression of Raf1 and PKCζ. Elevated expression of toll-like receptor (TLR)2, TLR1, and CD14 in mature EXE and PB granulocytes supports a role for the TLR2 and CD14 pathway in zymosan-mediated respiratory burst activity. Lower activity in EXE granulocytes may be due to greater expression of IRAK3, which inhibits TLR-mediated signaling.
Abundance of dinucleotide repeats and gene expression are inversely correlated: a role for gene function in addition to intron length
Authors: Sharma Vineet K. , Kumar Naveen , Brahmachari Samir K. , Ramachandran Srinivasan
Published: June 2007

High and broad transcription of eukaryotic genes is facilitated by cost minimization, clustered localization in the genome, elevated G+C content, and low nucleosome formation potential. In this scenario, illumination of correlation between abundance of (TG/CA)n≥12repeats, which are negative cis modulators of transcription, and transcriptional levels and other commonly occurring dinucleotide repeats, is required. Three independent microarray datasets were used to examine the correlation of (TG/CA)n≥12and other dinucleotide repeats with gene expression. Compared with the expected equi-distribution pattern under neutral model, highly transcribed genes were poor in repeats, and conversely, weakly transcribed genes were rich in repeats. Furthermore, the inverse correlation between repeat abundance and transcriptional levels appears to be a global phenomenon encompassing all genes regardless of their breadth of transcription. This selective pattern of exclusion of (TG/CA)n≥12and (AT)n≥12repeats in highly transcribed genes is an additional factor along with cost minimization and elevated GC, and therefore, multiple factors govern high transcription of genes. We observed that even after controlling for the effects of GC and average intron lengths, the effect of repeats albeit somewhat weaker was persistent and definite. In the ribosomal protein coding genes, sequence analysis of orthologs suggests that negative selection for repeats perhaps occurred early in evolution. These observations suggest that negative selection of (TG/CA)n≥12microsatellites in the evolution of the highly expressed genes was also controlled by gene function in addition to intron length.
GABA Inhibition of Cyclic AMP Production in Immortalized GnRH Neurons Is Mediated by Calcineurin-Dependent Dephosphorylation of Adenylyl Cyclase 9
Authors: Martin Cecilia , Jacobi Jessica S. , Nava Gabriel , Jeziorski Michael C. , Clapp Carmen , Martínez de la Escalera Gonzalo
Published: June 2007

The neurotransmitter γ-aminobutyric acid (GABA) is an important modulator of gonadotropin-releasing hormone (GnRH), and consequently of reproduction. GABA, acting via ionotropic GABAA receptors, exerts a biphasic effect on GnRH secretion in immortalized GnRH cells. The initial increase in GnRH secretion is triggered by a sharp rise in [Ca2+]i, while the progressive decline of GnRH levels that follows is paralleled by reduced levels of intracellular cAMP. The experiments described here were designed to explore the potential signaling pathways involved in this novel GABAA ionotropic inhibition of cAMP synthesis in GT1–7 cells. Using RT-PCR and real-time PCR, we found that GT1–7 cells express 8 of 9 known membrane adenylyl cyclase (AC) isoforms, including a large proportion of AC3 and AC9, as well as AC5 and AC6, all of which are negatively regulated by increases in [Ca2+]i. In contrast, isoforms of AC that are positively regulated by [Ca2+]i were barely detectable (AC1) or undetectable (AC8). Pharmacological activation of L-type voltage-operated calcium channels with BayK 8644 produced a decrease in [cAMP]i similar to that induced by GABA, while blocking these calcium channels with verapamil reversed the effect of GABA on cAMP synthesis. Furthermore, blocking calcineurin with deltamethrin, FK-506 or cyclosporin A blocked the inhibitory effect of GABA on [cAMP]i, supporting the involvement of AC9 in this effect. In addition, blocking Ca2+/calmodulin-dependent protein kinase II (CamKII) with KN-62 partially reversed the action of GABA, suggesting that AC3 may also be involved in this effect. Finally, GABA increased phosphatase activity in a calcium-dependent manner, an effect blocked by calcineurin inhibitors. Collectively, our results show that the ionotropic action of GABA via the activation of GABAA receptors can decrease AC activity in immortalized GnRH neurons, and that the effect of GABA appears to be mediated by a transient increase in [Ca2+]i followed by activation of calcineurin and CamKII, leading to dephosphorylation of AC9 and phosphorylation of AC3, respectively, and subsequently reducing the synthesis of cAMP.
Revisiting the Generalized Other: An Exploration
Authors: Holdsworth Clare , Morgan David
Published: June 2007

In examining transcripts of inter views conducted as par t of an investigation of the process of leaving the parental home, we were frequently reminded of Mead's idea of `the generalized other'. This ar ticle explores the usefulness of this somewhat neglected idea. After examining the possible range of meanings suggested by this idea and affinities with other concepts (especially Bourdieu's notion of `habitus') we develop this idea through the use of three case studies taken from inter views in three different cities. We consider normative points of comparison, reflexivity and the generalized other and judgements about other people. We conclude that Mead's idea continues to have considerable usefulness, in par ticular in relation to what might be turned a recent `ethical turn' in social enquiry.
`Things are Getting Better all the Time'?
Authors: Everingham Christine , Stevenson Deborah , Warner-Smith Penny
Published: June 2007

This ar ticle addresses the dilemmas associated with continuing to interpret women's experience through the lens of a progress narrative that emerged to represent the aspirations of women during the peak of the women's movement. The central theme of this narrative is that gender will no longer act as a social constraint once women are recognized as workers as well as mothers. Drawing on the theoretical framework of Karl Mannheim and empirical data from in-depth inter views under taken as par t of a generational study of Australian women, the ar ticle argues that the progress narrative no longer inspires young women, who take gender equity for granted. Although motherhood continues to shape their working arrangements, the discourses they use to make sense of the tensions involved are embedded in a new Zeitgeist which prioritizes `choice', not `equity'. The implications of this shift for the `work-life balance' social policy agenda are then considered.
Parental Divorce and Children's Socio-economic Success: Conditional Effects of Parental Resources Prior to Divorce, and Gender of the Child
Authors: Fischer Tamar
Published: June 2007

Both the level and allocation of pre-divorce parental and family resources may be impor tant predictors for the effects of divorce on child outcomes. This study estimates specific divorce effects on socio-economic outcomes of children in families having a different amount and allocation of both cultural and economic resources. In addition, this study tests whether general divorce effects differ between boys and girls. Data are used from the Family Sur vey Dutch Population 1998 (FSDP98) and the Family Sur vey Dutch Population 2000 (FSDP00) (De Graaf et al., 1998, 2000). The first conclusion was that a high level of paternal resources increases divorce effects on children's educational level and their occupational status. Moreover, a high level of maternal resources decreases the divorce effect. These findings suppor t the loss of resources theory. Finally, practically no differences in general divorce effects were found when boys and girls were compared.
Anthony Giddens as Adversary of Class Analysis
Authors: Atkinson Will
Published: June 2007

The special issue of Sociology on `Class, Culture and Identity' illustrated how often Anthony Giddens is cited as an antagonist of class *theor y. It comes as some surprise, then, to find that his exact view on the demise of class has, to date, received remarkably little in the way of substantial exposition and critique.This ar ticle seeks to fill this void by outlining Giddens' theor y of the reflexive project of the self in late modernity and its precise consequences for the concept of class, moving on from that to distinguish it from the kindred ideas of Beck and to suggest some of its key failings. Finally, I suggest the ways these problems can be overcome — and class salvaged in the process — by turning to Bourdieu.
When Jack Gets out of the Box: The Problems of Regulating a Global Industry
Authors: Sampson Helen , Bloor Michael
Published: June 2007

This ar ticle considers the challenge of regulation across national borders using the example of the shipping industry. It examines the success of different global regulator y strategies in the sector, specifically the implementation of smar t regulation and enforced self-regulation. In doing so it draws upon empirical research into the enforcement of labour standards via por t-State control in India, Russia and the UK, and the regulation of training in Singapore, Philippines and the UK. It concludes that effective global regulation faces considerable challenges. Within the relatively conducive environment of shipping it finds that smar t regulation has been vitiated by perceived inconsistency in inspection practice and that enforced self-regulation has been rendered less effective by cross-national differences in resourcing and regulator y commitment, compounded by the difficulties of paper-based validation. It argues that, in relation to issues of effective global governance, the shipping industr y may stand as a critical case.
Contested Professionalism Payments for Care and the Quality of Home Care
Authors: Knijn Trudie , Verhagen Stijn
Published: June 2007

In the recent past, policy makers have emphasized the benefits and positive aspects of direct payments for care of frail elderly people. In this article, the authors present the theoretical framework of “struggling logics of home care,” by means of which they explore the underlying logics of the introduction of payments for care: market, family, and state. More specifically, the authors show the strengths and weaknesses of a fourth logic—professionalism—and expound how this logic is submitted to marketized and familialized payments for care. The authors conclude that there are indeed some positive aspects of the trend toward payments for care. However, (female) professional home care workers benefit hardly at all. On the long term, this could also erode the quality of care provided to recipients.
The Impact of Individual Expectations and Expectation Conflicts on Virtual Teams
Authors: Bosch-Sijtsema Petra
Published: June 2007

Virtual teams are characterized by geographical dispersion, organizational, and cultural heterogeneity, and their members have little history and lateral and weak relationships. Literature denotes the importance of expectations in virtual settings, but individual expectations of virtual team members are hardly investigated. In this article, the author discusses the presence of different kinds of expectations and the impact of mismatches of individual expectations within virtual teams. Psychological contract literature states that expectation mismatches result in negative outcomes, whereas learning literature posits that mismatches enhance learning. These concepts addressing mismatches of expectations are discussed as a theoretical paradox.
Promoting enjoyment in girls' physical education: The impact of goals, beliefs, and self-determination
Authors: Wang C.K. John , Liu W.C.
Published: June 2007

This study examined the network of relationships between spor t ability beliefs, achievement goals, self-determination and female students' enjoyment in school physical education (PE). Female secondar y students ( n = 343) from a single-sex secondar y school in Singapore par ticipated in the survey. They were assessed on spor t ability beliefs, goal orientations, relative autonomy, perceived competence and enjoyment in PE. The findings established that incremental belief predicted task orientation. In addition, relative autonomy, task orientation and perceived competence had strong and direct impact on enjoyment. Overall, the present study offers some insightful thoughts for promoting enjoyment for girls in PE and physical activity.
The contextual interference effect in applied settings
Authors: Barreiros João , Figueiredo Teresa , Godinho Mário
Published: June 2007

This paper analyses the research literature that approaches the contextual interference effect in applied settings. In contrast to the laboratory settings, in which high interference conditions depress acquisition and promote learning evaluated in retention and transfer tests, in applied settings most of the studies (60%) fail to observe positive effects after manipulation of the contextual interference. Some possible explanations for the fact are hypothesized regarding the characteristics of the task, with serial tasks doing best, shor t inter trial intervals rare in applied settings, interference produced by the use of different motor programmes and the possible interference of concurrent feedback in slow tasks in contrast to ballistic skills. It seems that there is a more evident contextual interference effect in an applied setting, when subject learns a serial task with high degree of complexity.
Learning to teach sport education: The experiences of a pre-service teacher
Authors: McMahon Eileen , MacPhail Ann
Published: June 2007

This paper repor ts on a study of one pre-ser vice teacher's implementation of the spor t education (SE) model in a post-primar y school in Ireland. The study sought to identify and understand the mechanisms that facilitate or inhibit learning to teach the model from the perspective of a pre-ser vice teacher. Occupational socialization was used to examine how past teaching experiences, physical education teacher education (PETE) and school culture influenced and impacted on the experience of learning to teach the SE model. Qualitative data are repor ted from inter views and diar y entries. Findings reveal that professional socialisation occurring in PETE had the most influence on the pre-ser vice teacher's experience of learning to teach the model. A number of recommendations are made for teacher education and for professional development specialists attempting to improve professional development oppor tunities and facilitate curricular change.
Use-Dependent Up- and Down-Regulation of Sensorimotor Brain Circuits in Stroke Patients
Authors: Lindberg PÅvel G. , Schmitz Christina , Engardt Margareta , Forssberg Hans , Borg Jörgen
Published: June 2007

Objective. To examine whether cerebral activity during passive movements decreases with time after stroke, and if reduced activity in the representation for the upper extremity can be reversed with training. Methods. Brain activity was measured by functional magnetic resonance imaging (fMRI) during passive wrist flexion-extension in 7 patients at varying time points after stroke, in a cross-sectional design. Upper limb function was also measured in all patients. Five of the patients took part in a training program and were measured again, behaviorally and with fMRI posttraining. Healthy control individuals of comparable age were also studied. Results. In patients, reduced activity over time after stroke was found for the group in the supplementary motor area (SMA), contralateral primary motor cortex, and prefrontal and parietal association areas along with ipsilateral cerebellum. Activity in most of these areas was also reduced in the patient group as compared to the control group. After a half-hour of daily training for 4 weeks with repetitive passive and active arm movements, cerebral activation increased in the pre-SMA and SMA, ipsilateral primary sensory cortex and intraparietal sulcus, and contralateral cerebellum in parallel with functional improvements of the upper limb. Areas common to both analyses included the SMA, pre-SMA, primary sensory cortex, intraparietal sulcus, and cerebellum. Conclusions. Our findings suggest that a down-regulation of sensorimotor activity occurs progressively over time as a result of inactivity and that training may reverse the reduced brain activity.
Test-Retest Reliability of 24 Hours of Activity Monitoring in Individuals With Parkinson's Disease in Home and Community
Authors: White Daniel K. , Wagenaar Robert C. , Del Olmo Mary E. , Ellis Terry D.
Published: June 2007

Background/Objective . This study examined the test-retest reliability of an activity monitor (AM) in home and community settings in individuals with Parkinson's disease (PD). Methods. Nine independent community dwellers with idiopathic PD were recruited (8 males and 1 female; median age = 66 years, range 46-71; Hoehn & Yahr score 2). Patients wore the AM for 3 separate sessions in the home and community with 7 days between each session. The first 2 sessions lasted 24 hours each, and the third session lasted 48 hours. Reliability indices and measures of variability were obtained by using intraclass correlation coefficients (ICC) and generalizability coefficients. The functional activity measures included the percentage of time spent in sleeping positions, sitting, standing, and walking; the number of transitions between sit and stand; the total number of transitions; the number of walking periods lasting 5 and 10 seconds; and stride frequency. Results. The ICCs for functional activities between the first and second consecutive days for the 48-hour session (third session) ranged from .76 to .92. The ICCs for the 7- and 14-day intervals ranged from .45 to .96, with walking-related measures showing the highest ICCs (range = .81 to .96). Across the three 24-hour periods (sessions 1 and 2, and the first 24 hours of session 3), the ICCs for walking-related measures were again high ranging from .87 to .92. Walking-related measures demonstrated the highest generalizability coefficients, indicating these measures have the highest test-retest reliability in comparison to other functional activity measures. Conclusions. The present study shows that 24 hours of recording with an AM is a sufficient duration of time to reliably record patients' functional activity in the home and community settings. In addition, the highest test-retest reliability for activities across 7- and 14-day intervals were found for walking-related measures in individuals with PD, indicating these measures have the highest stability compared to the other measures of functional activity.
Comparison of Speeds Used for the 15.2-Meter and 6-Minute Walks Over the Year After an Incomplete Spinal Cord Injury: The SCILT Trial
Authors: Barbeau H. , Elashoff R. , Deforge D. , Ditunno J. , Saulino M. , Dobkin B.H.
Published: June 2007

Background. Timed walking speed for 6 to 15 m and the distance walked in 2 to 12 minutes are frequently used outcome measures in rehabilitation trials, presumably reflecting different aspects of walking ability. The database from the Spinal Cord Injury Locomotor Trial (SCILT), which tested 2 interventions for mobility upon admission for initial rehabilitation of an incomplete traumatic spinal cord injury (SCI), was used to compare the walking speed employed for each test. Methods. From 66 to 70 patients with upper motor neuron lesions from C-5 to T-10 performed a 15.2-m and a 6-minute walk as fast as the patient deemed safe at 3 months (end of the trial intervention) and 6 and 12 months after entry. The means, standard errors, and quartiles were calculated for the speed used for each task. Results. The mean speed for the 15.2-m walk did not differ from that used for the 6-minute walk at 3 and 6 months but was significantly faster at 12 months. Differences became apparent at each assessment in patients in the highest quartiles (>1.0 m/s) for the 15.2-m walk. Their speed was from 14% to 24% higher than the speed used for the 6-minute walk. Conclusion. The speed of the 15.2-m walk as a measure of walking ability compared to the distance walked in 6 minutes may not represent separable domains of mobility. Differences were apparent only in the most highly functional patients, who could ambulate in the community. Any difference in the walking speed used for these 2 tasks does not make enough of a clinical distinction to encourage including both a 6-minute walk and a 15.2-m walk as outcome measures in clinical trials of locomotor interventions for SCI.
Effective media communication of disasters: Pressing problems and recommendations
Authors: Lowrey Wilson , Evans William , Gower Karla K , Robinson Jennifer A , Ginter Peter M , McCormick Lisa C , Abdolrasulnia Maziar
Published: June 2007

Background

Public health officials and journalists play a crucial role in disseminating information regarding natural disasters, terrorism and other human-initiated disasters. However, research suggests that journalists are unprepared to cover terrorism and many types of natural disasters, in part because of lack sufficient expertise in science and medicine and training. The objective of this research was to identify solutions to problems facing journalists and public health public information officer (PIOs) of communicating with the public during natural and human-initiated disasters.

Methods

To assist in identifying the most pressing problems regarding media response to health-related risks such as terrorism and large-scale natural disasters, 26 expert advisors were convened, including leaders representing journalists and public information officers, state health officials, experts in terrorism and emergency preparedness, and experts in health, risk, and science communication. The advisory group participated in pre-arranged interviews and were asked to identify and review bioterrorism educational resources provided to journalist. All advisory group members were then invited to attend a day long meeting January 29, 2004 to review the findings and reach consensus.

Results

The most pressing problems were found to be a lack of coordination between PIO's and journalists, lack of resources for appropriately evaluating information and disseminating it efficiently, and a difference in perception of PIO's and journalist towards each others role during emergency situations. The advisory board developed a list of 15 recommendations that may enhance communication plans betweens PIO's, journalist and the public. The solutions were meant to be feasible in terms of costs and practical in terms of the professional and organizational realities in which journalists and PIO's work.

Conclusion

It is clear that PIO's and journalists play crucial roles in shaping public response to terrorism and other disasters. The findings from this formative research suggest that perspectives and organizational processes often limit effective communication between these groups; though practical solutions such as participation of journalists in drills, scenario exercises, sharing of informational resources, and raising awareness at professional trade meetings may enhance the timely dissemination of accurate and appropriate information.
Injection drug use and patterns of highly active antiretroviral therapy use: an analysis of ALIVE, WIHS, and MACS cohorts
Authors: Morris John D , Golub Elizabeth T , Mehta Shruti H , Jacobson Lisa P , Gange Stephen J
Published: June 2007

Background

Sustained use of antiretroviral therapy has been consistently shown to be one of the primary predictors of long-term effectiveness. Switching and discontinuation reflect patient and provider decisions that may limit future treatment options. In this study, we utilize data reported at semi-annual study visits from three prospective cohort studies, the AIDS Link to IntraVenous Exposure (ALIVE), the Women's Interagency HIV Study (WIHS), and the Multicenter AIDS Cohort Study (MACS), to investigate determinants of HAART modification with a particular focus on reported injection drug use (IDU).

Methods

Longitudinal data collected between 1996 and 2004 contributed from 2,266 participants (37% with a reported history of IDU) who reported initiating their first HAART regimen during follow-up were utilized. Separate proportional-hazards models were used to identify factors measured prior to HAART-initiation associated with the time to first HAART discontinuation and first switch of components of HAART among continuous HAART users.

Results

The use of PI- vs. NNRTI-based regimens among HAART users with and without any history of IDU was similar over follow-up. The median time to a first report of discontinuation of HAART was 1.1 years for individuals with a history of IDU but 2.5 years for those without a history of IDU and multivariate analyses confirmed overall that individuals with a history of IDU were at greater risk for HAART discontinuation (adj RH = 1.24, 95% CI: 1.03–1.48). However, when restricting to data contributed after 1999, there was no longer any significant increased risk (adj RH = 1.05, 95% CI: 0.81–1.36). After adjusting for pre-HAART health status and prior ARV exposure, individuals who were ethnic/racial minorities, reported an annual income < $10,000/year, and were not employed were at significantly greater risk for HAART discontinuation. The median time to a first change in HAART regimen was approximately 1.5 years after first HAART report and was not elevated among those with a history of IDU (adj RH = 1.09, 95% CI: 0.89–1.34).

Conclusion

Our analyses demonstrate that injection drug use by itself does not appear to be an independent risk factor for HAART switching or discontinuation in more recent years. However, as continued HAART use is of paramount importance for long-term control of HIV infection, efforts to improve maintenance to therapy among disadvantaged and minority populations remain greatly needed.
Targeting services to reduce social inequalities in utilisation: an analysis of breast cancer screening in New South Wales
Authors: Birch Stephen , Haas Marion , Savage Elizabeth , Van Gool Kees
Published: June 2007

Background

Many jurisdictions have used public funding of health care to reduce or remove price at the point of delivery of services. Whilst this reduces an important barrier to accessing care, it does nothing to discriminate between groups considered to have greater or fewer needs. In this paper, we consider whether active targeted recruitment, in addition to offering a 'free' service, is associated with a reduction in social inequalities in self-reported utilization of the breast screening services in NSW, Australia.

Methods

Using the 1997 and 1998 NSW Health Surveys we estimated probit models on the probability of having had a screening mammogram in the last two years for all women aged 40–79. The models examined the relative importance of socio-economic and geographic factors in predicting screening behaviour in three different needs groups – where needs were defined on the basis of a woman's age.

Results

We find that women in higher socio-economic groups are more likely to have been screened than those in lower groups for all age groups. However, the socio-economic effect is significantly less among women who were in the actively targeted age group.

Conclusion

This indicates that recruitment and follow-up was associated with a modest reduction in social inequalities in utilisation although significant income differences remain.
The PTPN221858C/T polymorphism is associated with anti-cyclic citrullinated peptide antibody-positive early rheumatoid arthritis in northern Sweden
Authors: Kokkonen Heidi , Johansson Martin , Innala Lena , Jidell Erik , Rantapää-Dahlqvist Solbritt
Published: June 2007

The PTPN22 1858C/T polymorphism has been associated with several autoimmune diseases including rheumatoid arthritis (RA). We have shown that carriage of the T variant (CT or TT) of PTPN22 in combination with anti-cyclic citrullinated peptide (anti-CCP) antibodies highly increases the odds ratio for developing RA. In the present study we analysed the association between the PTPN22 1858C/T polymorphism and early RA in patients from northern Sweden, related the polymorphism to autoantibodies and the HLA-DR shared epitope, and analysed their association with markers for disease activity and progression. The inception cohort includes individuals who also donated samples before disease onset. A case–control study was performed in patients (n = 505; 342 females and 163 males) with early RA (mean duration of symptoms = 6.3 months) and in population-based matched controls (n = 970) from northern Sweden. Genotyping of the PTPN22 1858C/T polymorphism was performed using a TaqMan instrument. HLA-shared epitope alleles were identified using PCR sequence-specific primers. Anti-CCP2 antibodies were determined using enzyme-linked immunoassays. Disease activity (that is, the number of swollen and tender joints, the global visual analogue scale, and the erythrocyte sedimentation rate) was followed on a regular basis (that is, at baseline and after 6, 12, 18 and 24 months). Both the 1858T allele and the carriage of T were associated with RA (χ2 = 23.84, P = 0.000001, odds ratio = 1.69, 95% confidence interval = 1.36–2.11; and χ2 = 22.68, P = 0.000002, odds ratio = 1.79, 95% confidence interval = 1.40–2.29, respectively). Association of the 1858T variant with RA was confined to seropositive disease. Carriage of 1858T and the presence of anti-CCP antibodies was independently associated with disease onset at an earlier age (P < 0.05 and P < 0.01, respectively), while the combination of both resulted in an even earlier age at onset. Smoking was identified as a risk factor independent of the 1858T variant and anti-CCP antibodies.
Fibrocytes in lung disease
Authors: Gomperts Brigitte N , Strieter Robert M
Published: June 2007

Fibrocytes were first described over a decade ago as a population of cells in circulation with fibroblast-like properties, which were involved in tissue repair. Since that time, we have learned a significant amount about these bone marrow-derived cells, which contribute to wound healing and fibrosis. Fibrocytes express leukocyte markers such as CD34, CD45, and CD13 and also express mesenchymal markers such as pro-collagens I and III, vimentin, and fibronectin. In addition, they have been shown to express the chemokine receptors CXCR4 and CCR7, which appear to be important in cellular trafficking from the vascular to the extravascular compartment. Fibrocytes have been shown to contribute to a number of fibrotic disorders, and here, we review their involvement in lung diseases including pulmonary fibrosis, asthma, and vascular remodeling.
Association of Serum Retinol-Binding Protein 4 and Visceral Adiposity in Chinese Subjects with and without Type 2 Diabetes
Authors: Jia Weiping , Wu Haiya , Bao Yuqian , Wang Chen , Lu Junxi , Zhu Jiehua , Xiang Kunsan
Published: June 2007

Objective: Previous studies have shown that adipose-derived serum retinol-binding protein 4 (RBP4) levels are increased in insulin-resistant mouse models and in subjects with insulin resistance or type 2 diabetes. However, the association of visceral fat and serum RBP4 has not been studied. The purpose of this study was to investigate the relationship between serum RBP4 and regional fat distribution in Chinese subjects with and without type 2 diabetes.

Design: We measured serum RBP4 concentrations from 1033 Chinese subjects with various degrees of obesity and tested the association between visceral adiposity and serum RBP4. In a subgroup of this study, euglycemic-hyperinsulinemic clamp was performed to measure insulin sensitivity. The association between visceral adiposity and serum RBP4 was also determined in response to rosiglitazone treatment in a subgroup of patients with diabetes.

Results: Serum RBP4 level was positively correlated with visceral adipose area in male (r = 0.171; P < 0.001) and female (r = 0.215; P < 0.001) subjects. However, there was no correlation between serum RBP4 and body mass index. Subjects with visceral obesity had higher serum RBP4 concentrations than those without visceral obesity in both men and women. Rosiglitazone treatment in patients with diabetes resulted in a lower serum RBP4 level (35.2 ± 10.2 vs. 24.9 ± 5.6 μg/ml, before vs. after treatment). These changes were accompanied by improved insulin sensitivity and reductions in visceral fat area. The latter was found to be highly correlated with the decline of serum RBP4 levels (r = 0.471; P = 0.027).

Conclusions: Serum RBP4 level is positively associated with visceral adiposity in both men and women. Our data suggest that RBP4 may contribute to the development of insulin resistance along with other adipokines.
Blood Glucose Control by a Model Predictive Control Algorithm with Variable Sampling Rate Versus a Routine Glucose Management Protocol in Cardiac Surgery Patients: A Randomized Controlled Trial
Authors: Hovorka Roman , Kremen Jaromir , Blaha Jan , Matias Michal , Anderlova Katerina , Bosanska Lenka , Roubicek Tomas , Wilinska Malgorzata E. , Chassin Ludovic J. , Svacina Stepan , Haluzik Martin
Published: June 2007

Context: Elevated blood glucose levels occur frequently in the critically ill. Tight glucose control by intensive insulin treatment markedly improves clinical outcome.

Objective and Design: This is a randomized controlled trial comparing blood glucose control by a laptop-based model predictive control algorithm with a variable sampling rate [enhanced model predictive control (eMPC); version 1.04.03] against a routine glucose management protocol (RMP) during the peri- and postoperative periods.

Setting: The study was performed at the Department of Cardiac Surgery, University Hospital.

Patients: A total of 60 elective cardiac surgery patients were included in the study.

Interventions: Elective cardiac surgery and treatment with continuous insulin infusion (eMPC) or continuous insulin infusion combined with iv insulin boluses (RMP) to maintain euglycemia (target range 4.4–6.1 mmol/liter) were performed. There were 30 patients randomized for eMPC and 30 for RMP treatment. Blood glucose was measured in 1- to 4-h intervals as requested by each algorithm during surgery and postoperatively over 24 h.

Main Outcome Measures: Mean blood glucose, percentage of time in target range, and hypoglycemia events were used.

Results: Mean blood glucose was 6.2 ± 1.1 mmol/liter in the eMPC vs. 7.2 ± 1.1 mmol/liter in the RMP group (P < 0.05); percentage of time in the target range was 60.4 ± 22.8% for the eMPC vs. 27.5 ± 16.2% for the RMP group (P < 0.05). No severe hypoglycemia (blood glucose < 2.9 mmol/liter) occurred during the study. Mean insulin infusion rate was 4.7 ± 3.3 IU/h in the eMPC vs. 2.6 ± 1.7 IU/h in the RMP group (P < 0.05). Mean sampling interval was 1.5 ± 0.3 h in the eMPC vs. 2.1 ± 0.2 h in the RMP group (P < 0.05).

Conclusions: Compared with RMP, the eMPC algorithm was more effective and comparably safe in maintaining euglycemia in cardiac surgery patients.
Highly Regioselective Hydrolysis of Substituted 2-Benzylidene-1,3-propylene Diacetates Using Porcine Pancreas Lipase
Authors: Miura Tsuyoshi , Kawashima Yuya , Umetsu Satoe , Kanamori Daisuke , Tsuyama Nanae , Jyo Yuki , Murakami Yasuoki , Imai Nobuyuki
Published: June 2007

Hydrolysis of substituted 2-benzylidene-1,3-propylene diacetates in the presence of 100 w/w % of porcine pancreas lipase (PPL) Type II proceeded to afford the corresponding Z-monoacetates in excellent yields with high regioselectivities.
A mouse model for Entamoeba histolytica infection
Authors: Owen Dawn G.
Published: June 2007

2 strains of Entamoeba histolytica, SAW 760 and SAW 408 (non-invasive zymodeme IX and invasive zymodeme II respectively, Sargeaunt & Williams 1979) were administered intra-intestinally to 15 inbred and 3 outbred strains of mouse. All were known to be free of the mouse amoeba E. muris. During the investigation, all animals were maintained in plastic film isolator units, under gnotobiotic conditions. Both zymodemes were found to be capable of infecting all 18 strains of mice for varying periods of time and both were capable of invading the gut mucosa in genetically susceptible strains. Mortality was high in some of the immunologically deprived strains, particularly with the more invasive strain of amoeba. 4 mouse strains: DBA/2, MRL, NZB, C57BL/6 bg, were found to be particularly good hosts to SAW 760.
Muscular dystrophy in the duck
Authors: Gopalakrishnakone P. , Voon F. C. T.
Published: June 2007

Clinical and gross anatomy features of myopathic ducks are reported. Light microscopic examination of the leg muscles showed necrosis, degeneration and inflammation, and some degree of regeneration was also observed. There was infiltration and replacement of muscle fibres with fibrous tissue. Electron microscopy showed the early stages of myofilament dissolution and accumulation of glycogen in the presynaptic terminal of the neuromuscular junction.
Death in leopard geckos (Eublepharis macularius) following ingestion of vermiculite
Authors: Pugsley S. L. , Spratt D. , Samour J. H.
Published: June 2007

This paper details the clinical and post-mortem findings of leopard geckos following ingestion of vermiculite bedding material. Death was attributed to the high magnesium content of the vermiculite.
The nutritional value of rat diets of differing energy and protein levels when subjected to physical processing
Authors: Dean Jill , Edwards D. G.
Published: June 2007

4 diets formulated to contain 8·5, 10·0, 11·5 and 12·5 MJ/kg metabolizable energy and 85, 133, 192 and 250 g/kg of protein respectively were prepared in 3 physical forms: meal, reground pellets or reground expanded and fed to growing rats from 28 to 56 days of age. Food intake was increased by pelleting and expanding in lower energy diets, whereas these differences tended to disappear in the higher energy diets. Growth and food conversion efficiencies showed a similar pattern, with the greatest differences evident in the low energy diets. Male rats showed greater differences than females in all parameters measured. Expanding the diet improved the microbiological status over pelleting both being superior to unprocessed meal. Measurements of digestible and metabolizable energy values of the 8·5 and 12·5 MJ/kg diets revealed consistent decreases in energy availability following processing. This suggested that the observed growth responses were due mainly to increased food intake coupled with increased nitrogen retention.
Rearing a second generation of cotton-top tamarins (Saguinus oedipus oedipus) in captivity
Authors: Kirkwood J. K. , Epstein M. A. , Terlecki A. J. , Underwood Susan J.
Published: June 2007

The average age at first parturition in captive-born female cotton-top tamarins was 31 months. Only 18% of full-term young born were successfully reared by primiparous females, but success increased with parity and 71% of babies born at 4th and 5th pregnancies were raised. 15% of litters were single births, 61% were twins and 24% were triplets. There was a seasonal distribution of births, with a clear peak in the spring months. The average interbirth interval was 294 days.
Management of craniotomy in young rabbits
Authors: Alberius P. , Klinge B. , Isaksson S.
Published: June 2007

A safe and easy-to-manage technique for various craniotomy procedures in young rabbits has been developed. This technique, which minimizes the need for special instrumentation, has been tested in 90 animals with a minimal mortality and morbidity: one death perioperatively caused by sagittal sinus bleeding and one rabbit disclosing a brief period of postoperative illness, respectively. The technique, including postsurgical strategy, is described in detail.
Heinz bodies do not modify the membrane characteristics of common marmoset (Callithrix jacchus) erythrocytes
Authors: Omorphos S. C. , Rice-Evans C. , Hawkey C.
Published: June 2007

The possibility was examined that the membrane function of erythrocytes obtained from healthy common marmosets ( Callithrix jacchus) was modified by the presence in the cells of Heinz bodies. No significant differences were found in erythrocyte endogenous free malonyl dialdehyde (MDA) or reduced glutathione (GSH) between normal human erythrocytes and marmoset erythrocytes containing Heinz bodies. Membrane fluorescent chromolipids, surface charge and thiol levels were similar in both species but average membrane bulk lipid fluidity was slightly elevated in the marmosets. It was concluded that, in contrast to the situation in human erythrocytes, the presence of Heinz bodies in red cells of marmosets does not adversely affect the properties of the membrane.