bluuebunny/crossref_metadata_2025 huggingface dataset:
Methamphetamine Use, Self-Reported Violent Crime, and Recidivism Among Offenders in California Who Abuse Substances
Authors: Cartier Jerome , Farabee David , Prendergast Michael L.
Published: February 2006

This study uses data from 641 state prison parolees in California to examine the associations between methamphetamine use and three measures of criminal behavior: (a) self-reported violent criminal behavior, (b) return to prison for a violent offense, and (c) return to prison for any reason during the first 12 months of parole. Methamphetamine use was significantly predictive of self-reported violent criminal behavior and general recidivism (i.e., a return to custody for any reason). However, methamphetamine use was not significantly predictive of being returned to custody for a violent offense. These trends remained even after controlling for involvement in the drug trade (i.e., sales, distribution, or manufacturing).
The Role of Perceptions in Dating Violence Among Young Adolescents
Authors: Próspero Moisés
Published: February 2006

The high prevalence of dating violence and the severity of its aftermath warrant the collaboration between research and practice for the development of prevention and intervention programs. This study investigates young adolescents’ perceptions of dating partner’s behaviors in common dating situations and their behavioral reaction to these dating situations. Initially, focus groups provided responses used for the development of a dating violence questionnaire. The questionnaire consisted of dating scenarios related to perceptions and expected behaviors of the characters in the scenarios. Second, another sample of adolescents responded to the scenarios. Descriptive statistics found that boys and girls reported fewer aggressive perceptions than aggressive behavioral responses to the dating scenarios. Nonparametric statistics revealed that adolescent boys were significantly more likely to expect aggressive responses than girls. These findings have implications for practitioners charged with preventing dating violence.
Community Violence Victimization and Symptoms of Posttraumatic Stress Disorder
Authors: Scarpa Angela , Haden Sara Chiara , Hurley Jimmy
Published: February 2006

This study tested the relationship of community violence (CV) victimization to severity of posttraumatic stress disorder (PTSD), and the roles of coping style and perceived social support in moderating that relationship. Three-hundred seventy-two men and women (age 18 to 22 years) self-reported on CV exposure, traumatic experiences, PTSD symptoms, perceived support from family and friends, and coping strategies. Results indicated that high CV victimization, high disengagement coping (i.e., avoidant styles), and low perceived social support from family and friends significantly predicted increased PTSD scores. Significant moderating effects indicated that the relationship between victimization and heightened PTSD severity was stronger at high levels of perceived friend support and disengagement. Thus, the protective function of friend support seemed to break down at increasing levels of victimization, whereas, as expected, avoidant styles of coping increased the risk for negative outcome. Findings are discussed in terms of event controllability, negative social reactions, and coping resources.
Association of Sexual Revictimization With Sexuality and Psychological Function
Authors: Miner Michael H. , Flitter Jill M. Klotz , Robinson Beatrice (Bean) E.
Published: February 2006

This study explores the associations of sexual revictimization (experiencing sexual abuse in childhood and adulthood) in a sample of 230 African American women who are low-income. Data indicate that women who experience sexual revictimization are more at risk for emotional stress and psychological pathology than women with no history of abuse. In addition, women who are revictimized appear to be at greater risk for emotional problems than women sexually abused only as a child or sexually assaulted only as adults. Revictimization also appears to be associated with an increased probability of engaging in prostitution, even higher than women with childhood- or adult-only victimization, who showed increased probability when compared to women never abused. Finally, women who are revictimized showed increased HIV risk, in that they were 4 times less likely than other women to consistently use condoms, but no more likely to be in monogamous relationships or less likely to have multiple partners.
Definitions of and Beliefs About Wife Abuse Among Ultra-Orthodox Jewish Men From Israel
Authors: Steinmetz Simona , Haj-Yahia Muhammad M.
Published: February 2006

This article presents a study conducted among 148 men from the ultra-Orthodox Jewish community in Israel. A self-administered questionnaire was utilized to examine their definitions of and beliefs about wife abuse. The definitions provided by the majority of the participants were highly consistent with definitions that are accepted in the professional literature. The majority of participants tended to view wife abuse as unjustified and held violent husbands responsible for their behavior. They were also in favor of helping women who were abused. At the same time, however, some participants showed a tendency to blame women for violence against them and indicated that the reasons why women stay with husbands who are abusive can be attributed more to external factors than to her internal situation. Substantial amounts of the variance in the participants’ definitions of and beliefs about wife abuse can be explained by the extent of their patriarchal ideology. Limitations and recommendations for future research are discussed.
A Vicious Oval
Authors: Larsen Elizabeth A.
Published: February 2006

This article explores the gendered contradictions of visibility for self-employed women in male-dominated occupations. It provides a link between the extant literature on women’s workplace issues with visibility and the recent, dramatic increase in self-employed women, especially those who work in male-dominated fields. The author uses a harness-horse racetrack as the site for exploring the social mechanisms behind the invisibility and negative visibility experienced by these women in their work. Through an ethnographic study of their daily work experiences, an insidious pattern of events surfaced in which every path leads to the same endpoint: the underutilization of self-employed women in a male-dominated field. This article also explores the social processes and pressures that lead these women to contribute to their own oppression in male-dominated fields.
“The Dog You Deserve”
Authors: Sanders Clinton R.
Published: February 2006

Primarily based on ethnographic fieldwork in a police K-9 training program, this article first presents the optimal attributes of patrol dogs and their handlers. It then moves to a discussion of the training process and emphasizes the apparent disjunction between defining the dog as a law enforcement tool, on one hand, and a unique and sentient individual, on the other. Following a description of key elements of the day-to-day work of the K-9 unit, the article discusses the uneasiness that handlers (and police administrators) feel due to the potential conflict between treating the patrol dog as an effective weapon/deterrent and treating it as a reliable companion/partner and docile family member. The article concludes with a brief examination of ambivalence as a general feature of social life and a unique characteristic of the occupation life of the K-9 police officer.
Resistance under the Black Light
Authors: Egan R. Danielle
Published: February 2006

This article examines how exotic dancers strategically use music in two exotic dance clubs in the New England area. Music functioned as a form of resistance for dancers in three ways: as a direct form of protest against owners, as a covert strategy of reappropriation, and as an overt expression of discontent in their interactions with regular customers. I also analyze the ways in which “buying against” gender inequality, through the use of music, falls short as a form of protest. For example, dancers often unwittingly fetishized the racial politics undergirding the genre of music. This research is informed by four years of ethnographic research in the New England area.
Authentic Identities
Authors: Williams J. Patrick
Published: February 2006

In this article, the author examines the relative roles of music and the internet for self-identifying members of the straightedge youth subculture. For nearly 30 years, subcultures have been conceptualized primarily in terms of music and style. Participation has therefore typically been characterized by the consumption of specific types of music and clothing and participation in local, face-to-face music scenes. However, with the recent growth of information and communication technologies like the internet, opportunities have emerged that enable individuals to participate in subcultures in which they otherwise might not participate. The author shows that a new type of subculturalist is emerging—one whose subcultural participation is limited to the internet. Using the concepts of authenticity and scene, the author explores how participants in a straightedge internet forum negotiate their affiliations with the subculture and how some members attempt to halt others’ claims to a straightedge identity. The study suggests that the internet is emerging as a new, but highly contested, subcultural scene.
E-selectin permits communication between PAF receptors and TRPC channels in human neutrophils
Authors: McMeekin Sarah R. , Dransfield Ian , Rossi Adriano G. , Haslett Christopher , Walker Trevor R.
Published: March 2006

The selectin family of molecules (L-, P-, and E-selectin) mediates adhesive interactions between leukocytes and endothelial cells required for recruitment of leukocytes to inflammatory sites. Soluble E-selectin levels are elevated in inflammatory diseases and act to promote neutrophil β2-integrin–mediated adhesion by prolonging Ca2+ mobilization. Although soluble E-selectin alone was unable to initiate Ca2+ signaling, it allowed a novel “permissive” store-operative calcium entry (SOCE) following the initial platelet-activating factor (PAF)–induced release of Ca2+ from inositol 1,4,5-trisphosphate (IP3)–sensitive stores. This induction of permissive SOCE in response to soluble E-selectin and PAF was shown to act through a G protein-coupled receptor (GPCR) coupled to pertussis toxin-insensitive Gq/11. Furthermore, we demonstrated that permissive SOCE was mediated by canonical transient receptor potential channel (TRPC) due to its sensitivity to specific inhibition by MRS1845 and Gd3+ and that TRPC6 was the principal TRPC family member expressed by human neutrophils. In terms of mechanism, we demonstrated that soluble E-selectin activated Src family tyrosine kinases, an effect that was upstream of phosphatidylinositol 3′-kinase in a signaling pathway that regulates permissive SOCE following exposure of neutrophils to PAF. In summary, this report provides the first evidence for communication between an inflammatory mediator and adhesion receptors at a molecular level, through selectin receptor ligation allowing permissive SOCE to occur following PAF stimulation of human neutrophils.
Reduced thrombus stability in mice lacking the α2A-adrenergic receptor
Authors: Požgajová Miroslava , Sachs Ulrich J. H. , Hein Lutz , Nieswandt Bernhard
Published: March 2006

Platelet activation plays a central role in hemostasis and thrombosis. Many platelet agonists function through G-protein–coupled receptors. Epinephrine activates the α2A-adrenergic receptor (α2A) that couples to Gz in platelets. Although α2A was originally cloned from platelets, its role in thrombosis and hemostasis is still unclear. Through analysis of α2A-deficient mice, variable tail bleeding times were observed. In vitro, epinephrine potentiated activation/aggregation responses of wild-type but not α2A-deficient platelets as determined by flow cytometry and aggregometry, whereas perfusion studies showed no differences in platelet adhesion and thrombus formation on collagen. To test the in vivo relevance of α2A deficiency, mice were subjected to 3 different thrombosis models. As expected, α2A-deficient mice were largely protected from lethal pulmonary thromboembolism induced by the infusion of collagen/epinephrine. In a model of FeCl3-induced injury in mesenteric arterioles, α2A–/– mice displayed a 2-fold increase in embolus formation, suggesting thrombus instability. In a third model, the aorta was mechanically injured, and blood flow was measured with an ultrasonic flow probe. In wild-type mice, all vessels occluded irreversibly, whereas in 24% of α2A-deficient mice, the initially formed thrombi embolized and blood flow was reestablished. These results demonstrate that α2A plays a significant role in thrombus stabilization.
GONOME: measuring correlations between GO terms and genomic positions
Authors: Stanley Stefan M , Bailey Timothy L , Mattick John S
Published: February 2006

Background:

Current methods to find significantly under- and over-represented gene ontology (GO) terms in a set of genes consider the genes as equally probable "balls in a bag", as may be appropriate for transcripts in micro-array data. However, due to the varying length of genes and intergenic regions, that approach is inappropriate for deciding if any GO terms are correlated with a set of genomic positions.

Results:

We present an algorithm – GONOME – that can determine which GO terms are significantly associated with a set of genomic positions given a genome annotated with (at least) the starts and ends of genes. We show that certain GO terms may appear to be significantly associated with a set of randomly chosen positions in the human genome if gene lengths are not considered, and that these same terms have been reported as significantly over-represented in a number of recent papers. This apparent over-representation disappears when gene lengths are considered, as GONOME does. For example, we show that, when gene length is taken into account, the term "development" is not significantly enriched in genes associated with human CpG islands, in contradiction to a previous report. We further demonstrate the efficacy of GONOME by showing that occurrences of the proteosome-associated control element (PACE) upstream activating sequence in the S. cerevisiae genome associate significantly to appropriate GO terms. An extension of this approach yields a whole-genome motif discovery algorithm that allows identification of many other promoter sequences linked to different types of genes, including a large group of previously unknown motifs significantly associated with the terms 'translation' and 'translational elongation'.

Conclusion:

GONOME is an algorithm that correctly extracts over-represented GO terms from a set of genomic positions. By explicitly considering gene size, GONOME avoids a systematic bias toward GO terms linked to large genes. Inappropriate use of existing algorithms that do not take gene size into account has led to erroneous or suspect conclusions. Reciprocally GONOME may be used to identify new features in genomes that are significantly associated with particular categories of genes.
Patient and health care system delays in the start of tuberculosis treatment in Norway
Authors: Farah Mohamed Guled , Rygh Jens Henning , Steen Tore W , Selmer Randi , Heldal Einar , Bjune Gunnar
Published: February 2006

Background

Delay in start of tuberculosis (TB) treatment has an impact at both the individual level, by increasing the risk of morbidity and mortality, and at the community level, by increasing the risk of transmission. The aims of this study were to assess the delays in the start of treatment for TB patients in Oslo/Akershus region, Norway and to analyze risk factors for the delays.

Methods

This study was based on information from the National TB Registry, clinical case notes from hospitals and referral case notes from primary health care providers. Delays were divided into patient, health care system and total delays. The association with sex, birthplace, site of the disease and age group was analyzed by multiple linear regression.

Results

Among the 83 TB patients included in this study, 71 (86%) were born abroad. The median patient, health care system and total delays were 28, 33 and 63 days respectively, with a range of 1–434 days. In unadjusted analysis, patient delay and health care system delay did not vary significantly between men and women, according to birthplace or age group. Patients with extra-pulmonary TB had a significantly longer patient, health care system and total delay compared to patients with pulmonary TB. Median total delay was 81 and 56 days in the two groups of TB patients respectively. The health care system delay exceeded the patient delay for those born in Norway. The age group 60+ years had significantly shorter patient delay than the reference group aged 15–29 years when adjusted for multiple covariates. Also, in the multivariate analysis patients born in Norway had significantly longer health care system delay than patients born abroad.

Conclusion

A high proportion of patients had total delays in start of TB treatment exceeding two months. This study emphasizes the need of awareness of TB in the general population and among health personnel. Extra-pulmonary TB should be considered as a differential diagnosis in unresolved cases, especially for immigrants from high TB prevalence countries.
An ultra-low-power image compressor for capsule endoscope
Authors: Lin Meng-Chun , Dung Lan-Rong , Weng Ping-Kuo
Published: February 2006

Background

Gastrointestinal (GI) endoscopy has been popularly applied for the diagnosis of diseases of the alimentary canal including Crohn's Disease, Celiac disease and other malabsorption disorders, benign and malignant tumors of the small intestine, vascular disorders and medication related small bowel injury. The wireless capsule endoscope has been successfully utilized to diagnose diseases of the small intestine and alleviate the discomfort and pain of patients. However, the resolution of demosaicked image is still low, and some interesting spots may be unintentionally omitted. Especially, the images will be severely distorted when physicians zoom images in for detailed diagnosis. Increasing resolution may cause significant power consumption in RF transmitter; hence, image compression is necessary for saving the power dissipation of RF transmitter. To overcome this drawback, we have been developing a new capsule endoscope, called GICam.

Methods

We developed an ultra-low-power image compression processor for capsule endoscope or swallowable imaging capsules. In applications of capsule endoscopy, it is imperative to consider battery life/performance trade-offs. Applying state-of-the-art video compression techniques may significantly reduce the image bit rate by their high compression ratio, but they all require intensive computation and consume much battery power. There are many fast compression algorithms for reducing computation load; however, they may result in distortion of the original image, which is not good for use in the medical care. Thus, this paper will first simplify traditional video compression algorithms and propose a scalable compression architecture.

Conclusion

As the result, the developed video compressor only costs 31 K gates at 2 frames per second, consumes 14.92 mW, and reduces the video size by 75% at least.
Estimating probabilities of peptide database identifications to LC-FTICR-MS observations
Authors: Anderson Kevin K , Monroe Matthew E , Daly Don S
Published: February 2006

Background

The field of proteomics involves the characterization of the peptides and proteins expressed in a cell under specific conditions. Proteomics has made rapid advances in recent years following the sequencing of the genomes of an increasing number of organisms. A prominent technology for high throughput proteomics analysis is the use of liquid chromatography coupled to Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR-MS). Meaningful biological conclusions can best be made when the peptide identities returned by this technique are accompanied by measures of accuracy and confidence.

Methods

After a tryptically digested protein mixture is analyzed by LC-FTICR-MS, the observed masses and normalized elution times of the detected features are statistically matched to the theoretical masses and elution times of known peptides listed in a large database. The probability of matching is estimated for each peptide in the reference database using statistical classification methods assuming bivariate Gaussian probability distributions on the uncertainties in the masses and the normalized elution times.

Results

A database of 69,220 features from 32 LC-FTICR-MS analyses of a tryptically digested bovine serum albumin (BSA) sample was matched to a database populated with 97% false positive peptides. The percentage of high confidence identifications was found to be consistent with other database search procedures. BSA database peptides were identified with high confidence on average in 14.1 of the 32 analyses. False positives were identified on average in just 2.7 analyses.

Conclusion

Using a priori probabilities that contrast peptides from expected and unexpected proteins was shown to perform better in identifying target peptides than using equally likely a priori probabilities. This is because a large percentage of the target peptides were similar to unexpected peptides which were included to be false positives. The use of triplicate analyses with a "2 out of 3" reporting rule was shown to have excellent rejection of false positives.
Assessing Precollege Science Education Outreach Initiatives: A Funder's Perspective
Authors: Felix Debra A. , Hertle Mark D. , Conley Jill G. , Washington Lori B. , Bruns Peter J.
Published: March 2006

We describe an assessment of the collective impact of 35 grants that the Howard Hughes Medical Institute (HHMI) made to biomedical research institutions in 1999 to support precollege science education outreach programs. Data collected from funded institutions were compared with data from a control group of institutions that had advanced to the last stage of review but had not been funded. The survey instrument and the results reveal outcomes and impacts that HHMI considers relevant for these programs. The following attributes are considered: ability to secure additional, non-HHMI funding; institution buy-in as measured by gains in dedicated space and staff; enhancement of the program director's career; number and adoption of educational products developed; number of related publications and awards; percentage of programs for which teachers received course credit; increase in science content knowledge; and increase in student motivation to study science.
The role of the peroxisome proliferator-activated receptor-α (PPAR-α) in the regulation of acute inflammation
Authors: Cuzzocrea Salvatore , Mazzon Emanuela , Di Paola Rosanna , Peli Angelo , Bonato Andrea , Britti Domenico , Genovese Tiziana , Muià Carmelo , Crisafulli Concetta , Caputi Achille P
Published: February 2006

The peroxisome proliferator-activated receptor-α (PPAR-α) is a member of the nuclear receptor superfamily of ligand-dependent transcription factors related to retinoid, steroid, and thyroid hormone receptors. The aim of the present study was to evaluate the role of the PPAR-α receptor on the development of acute inflammation. To address this question, we used two animal models of acute inflammation (carrageenan-induced paw edema and carrageenan-induced pleurisy). We report here that when compared with PPAR-α wild-type mice, PPAR-α knockout mice (PPAR-αKO) mice experienced a higher rate of the extent and severity when subjected to carrageenan injection in the paw edema model or to carrageenan administration in the pleurisy model. In particular, the absence of a functional PPAR-α gene in PPAR-αKO mice resulted in a significant augmentation of various inflammatory parameters (e.g., enhancement of paw edema, pleural exudate formation, mononuclear cell infiltration, and histological injury) in vivo. Furthermore, the absence of a functional PPAR-α gene enhanced the staining (immunohistochemistry) for FAS ligand in the paw and in the lung and the expression of tumor necrosis factor α and interleukin-1β in the lungs of carrageenan-treated mice. In conclusion, the increased inflammatory response observed in PPAR-αΚΟ mice strongly suggests that a PPAR-α pathway modulates the degree of acute inflammation in the mice.
Impairment of SHP-1 down-regulation in the lipid rafts of human neutrophils under GM-CSF stimulation contributes to their age-related, altered functions
Authors: Fortin Carl F , Larbi Anis , Lesur Olivier , Douziech Nadine , Fulop Tamas
Published: February 2006

It has been shown that the functions and the rescue from apoptosis by proinflammatory mediators of polymorphonuclear leukocytes (PMN) tend to diminish with aging. Here, we investigated the role of protein tyrosine phosphatases (PTP), especially Src homology domain-containing protein tyrosine phosphatase-1 (SHP-1), in the age-related, altered PMN functions under granulocyte macrophage-colony stimulating factor (GM-CSF) stimulation. The inhibition of PTP suggested a differential effect of GM-CSF on phosphatase activity in modulating PMN functions with aging. The down-regulation of phosphatase activity of immunopurified SHP-1 from lipid rafts of PMN of young donors was found significantly altered at 1 min of stimulation with aging. In young donors, SHP-1 is displaced from lipid rafts at 1 min of stimulation, whereas in the elderly, SHP-1 is constantly present. We assessed in PMN lipid rafts the phosphorylation of tyrosine and serine residues of SHP-1, which regulates its activity. We observed an alteration in the phosphorylation of tyrosine and serine residues of SHP-1 in PMN of elderly subjects, suggesting that GM-CSF was unable to inhibit SHP-1 activity by serine phosphorylation. GM-CSF activates Lyn rapidly, and we found alterations in its activation and translocation to the lipid rafts with aging. We also demonstrate that SHP-1 in the PMN of elderly is constantly recruited to Lyn, which cannot be relieved by GM-CSF. In contrast, in the young, the resting recruitment could be relieved by GM-CSF. Our results suggest an alteration of the SHP-1 modulation by GM-CSF in lipid rafts of PMN with aging. These alterations could contribute to the decreased GM-CSF effects on PMN.
Dendritic cell function in cytomegalovirus-infected patients with mononucleosis
Authors: Frascaroli Giada , Varani Stefania , Mastroianni Antonio , Britton Sven , Gibellini Davide , Rossini Giada , Landini Maria P , Söderberg-Nauclér Cecilia
Published: February 2006

Dendritic cells (DCs) are important target cells for human cytomegalovirus (HCMV) infection, and the virus has been shown to hamper the differentiation and maturation pathways of these cells in vitro. In the present study, we examined the function of monocyte-derived DCs obtained from immunocompetent individuals undergoing symptomatic HCMV infection in terms of immunophenotypic characteristics, pinocytosis, lymphocyte stimulation capacity, and cyto-chemokine secretion in comparison with DCs obtained from healthy controls. Immature and lipopolysaccharide (LPS)-stimulated DCs obtained from patients actively infected with HCMV expressed significantly lower levels of major histocompatibility complex (MHC) class II molecules. The inhibition of expression of MHC class II molecules by HCMV appeared to be functionally relevant, as mature DCs obtained from patients with HCMV mononucleosis were inefficient in stimulating proliferation of allogenic lymphocytes. Finally, the pattern of cyto-chemokines secreted by DCs obtained from patients with HCMV mononucleosis was characterized by a proinflammatory profile with an increased production of interleukin (IL)-1β, tumor necrosis factor α, CC chemokine ligand 2 (CCL2) and CCL3, and reduced secretion of IL-10 upon LPS stimulation. During symptomatic HCMV infection in the immunocompetent host, DCs exhibit an impaired immunophenotype and function. These effects may contribute to the viral-induced immunomodulation, which is often observed in HCMV-infected patients.
Polymorphonuclear neutrophils deliver activation signals and antigenic molecules to dendritic cells: a new link between leukocytes upstream of T lymphocytes
Authors: Megiovanni Anna Maria , Sanchez Françoise , Robledo-Sarmiento Macarena , Morel Céline , Gluckman Jean Claude , Boudaly Sarah
Published: February 2006

Polymorphonuclear neutrophils (PMNs) are rapidly recruited to tissues upon injury or infection. There, they can encounter local and/or recruited immature dendritic cells (iDCs), a colocalization that could promote at least transient interactions and mutually influence the two leukocyte populations. Using human live blood PMNs and monocyte-derived iDCs, we examined if these leukocytes actually interacted and whether this influenced DC function. Indeed, coculture with live but not apoptotic PMNs led to up-regulation of membrane CD40, CD86, and human leukocyte antigen (HLA)-DR on DCs. Whereas CD40 up-regulation was dependent on soluble factors released by PMNs, as determined in cultures conducted in different chambers, cell contact was necessary for CD86 and HLA-DR up-regulation, a process that was inhibited by anti-CD18 antibodies, indicating that CD18 ligation was required. We also found that via a cell contact-dependent mechanism, DCs acquired Candida albicans-derived antigens from live as well as from apoptotic PMNs and could thus elicit antigen-specific T lymphocyte responses. Altogether, our data demonstrate the occurrence of cross-talk between human PMNs and DCs and provide new insights into the immune processes occurring upstream of the interactions between DCs and T lymphocytes.
Inhibition of platelet-activating factor biosynthesis by adenosine and histamine in human neutrophils: involvement of cPLA2α and reversal by lyso-PAF
Authors: Flamand Nicolas , Lefebvre Julie , Lapointe Gabriel , Picard Serge , Lemieux Lise , Bourgoin Sylvain G , Borgeat Pierre
Published: February 2006

Leukotrienes (LT) and platelet-activating factor (PAF) are important lipid mediators of inflammation. We and others reported previously that autacoids such as adenosine, histamine, prostaglandin E2, and β-adrenergic agents inhibit LT biosynthesis in activated human polymorphonuclear leukocytes (PMN). In this study, we demonstrate that CGS-21680 (a selective agonist of the adenosine A2A receptor) and histamine also potently inhibit PAF biosynthesis in agonist [formyl Met-Leu-Phe (fMLP)]- and thapsigargin-activated human PMN. The observed inhibitions of PAF biosynthesis were reversed effectively by exogenous 1-O-alkyl-lyso-sn-glyceryl-3-phosphocholine (lyso-PAF), suggesting that these effects of CGS-21680 and histamine implicate the blockade of cytosolic phospholipase A2α (cPLA2α) activity and lyso-PAF release and that the acetyl-coenzyme A/lyso-PAF acetyl transferase is not inhibited by the autacoids. Accordingly, the cPLA2α inhibitor pyrrophenone completely blocked PAF formation, and lyso-PAF similarly prevented this effect of pyrrophenone. The inhibitory effects of CGS-21680 and histamine on PAF biosynthesis were prevented by the protein kinase A inhibitor H-89, supporting roles for the Gs-coupled receptors A2A and H2, respectively, and cyclic adenosine monophosphate in the inhibitory mechanism. The fMLP-induced phosphorylations of p38 and extracellular signal-regulated kinase 1/2 were not altered significantly by the CGS-21680, indicating that inhibition of these kinases is not involved in the inhibitory effect of the adenosine A2A receptor ligand on LT and PAF biosynthesis. These data further emphasize the multiple and potent inhibitory effects of adenosine and histamine on leukocyte functions, in particular, on the biosynthesis of two classes of important lipid mediators and their putative regulatory roles in immune processes in health and diseases.
Coupling of C3bi to IgG inhibits the tyrosine phosphorylation signaling cascade downstream Syk and reduces cytokine induction in monocytes
Authors: Trinidad Antonio García , De la Puerta María Luisa , Fernández Nieves , Bayón Yolanda , Crespo Mariano Sánchez , Alonso Andrés
Published: February 2006

The effect of coupling C3bi to immunoglobulin G (IgG) immune complexes (IC) on their ability to produce protein tyrosine phosphorylation and activation of the mitogen-activated protein kinase (MAPK) and the Akt/protein kinase B (PKB) routes was assessedin human monocytes. Cross-linking Fc receptors for IgG activated the protein tyrosine kinase Syk, phospholipases Cγ1 and Cγ2, the MAPK cascade, and the Akt/PKB route. Linkage of C3bi to the γ-chain of IgG produced a decrease of the protein bands displaying tyrosine phosphorylation, whereas the MAPK cascades and the Akt/PKB route remained almost unaffected. Zymosan particles, which because of their β-glucan content mimic the effect of fungi, produced a limited increase of tyrosine-phosphorylated protein bands, whereas treatment of zymosan under conditions adequate for C3bi coating increased its ability to induce protein tyrosine phosphorylation. Noteworthy, this was also observed under conditions where other components of serum might be bound by zymosan particles, for instance, serum IgG, thereby suggesting their potential involvement in Syk activation. The induction of cytokines showed a changing pattern consistent with the changes observed in the signaling pathways. IC induced monocyte chemoattractant protein-1 (MCP-1)/CC chemokine ligand 2 (CCL2), interleukin (IL)-1β, and eotaxin-2/CCL24, which were not observed with C3bi-coated IC. Zymosan induced the expression of tumor necrosis factor α (TNF-α), TNF-β, IL-10, IL-6, and MCP-2/CCL8, whereas the cytokine signature of C3bi-coated zymosan also included interferon-inducible protein 10/CXC chemokine ligand 10, platelet-derived growth factor-BB, and I-309/CCL1. Taken together, these findings indicate that C3bi targets the phagocytic cargo, and engagement or diversion of the Syk route determines the phagocyte response.
A novel shrinkage technique based on the normal inverse Gaussian density model
Authors: Shang Li , Li Kang , Lok Tat-Ming , Lyu Michael R.
Published: February 2006

This paper proposes a novel image denoising technique based on the normal inverse Gaussian (NIG) density model using an extended non-negative sparse coding (NNSC) algorithm proposed by us. This algorithm can converge to feature basis vectors, which behave in the locality and orientation in spatial and frequency domain. Here, we demonstrate that the NIG density provides a very good fitness to the non-negative sparse data. In the denoising process, by exploiting a NIG-based maximum a posteriori estimator (MAP) of an image corrupted by additive Gaussian noise, the noise can be reduced successfully. This shrinkage technique, also referred to as the NNSC shrinkage technique, is self-adaptive to the statistical properties of image data. This denoising method is evaluated by values of the normalized signal to noise rate (SNR). Experimental results show that the NNSC shrinkage approach is indeed efficient and effective in denoising. Otherwise, we also compare the effectiveness of the NNSC shrinkage method with methods of standard sparse coding shrinkage, wavelet-based shrinkage and the Wiener filter. The simulation results show that our method outperforms the three kinds of denoising approaches mentioned above.
GA-based control to swing up an acrobot with limited torque
Authors: Zhao Dongbin , Yi Jianqiang
Published: February 2006

To swing up an acrobot, a two-link under-actuated robotic system, a fuzzy neural network (FNN) controller with limited torque based on genetic algorithm (GA) is presented and tested. The acrobot is composed of two links rotating in a same plane around two joints, only the second of which is actuated. The upswing process is a complex problem to rotate the two links from the low to the top balance position by single torque on the actuated joint. In a real application system, motor output is often limited. Therefore, an FNN controller is proposed to generate limited torque on the actuated joint according to different states of the two links. The antecedents and consequences of the FNN controller are determined with an improved GA. Simulation results on the acrobot system verify the feasibility and generalization of the proposed GA-based FNN control scheme.
Design of UPFC controller in large-scale power systems based on immune genetic algorithm
Authors: Jiang Quanyuan , Zou Zhenyu , Wang Zhiyong , Cao Yijia
Published: February 2006

This paper proposed a new optimization algorithm-immune genetic algorithm (IGA), which is based on immune genetic theory of creatures and can simulate the immune system and its behaviour in organisms. Compared with common genetic algorithms, the IGA adopts the following techniques to improve the global searching ability and convergence speed: immune memory, immune selection, concentration control, niching technique, chaos production and metabolism. Several typical test functions are used to verify the excellent performances of the proposed IGA. Finally, the IGA is applied to optimize the parameters of a unified power flow controller (UPFC) to improve the stability of the New England Test Power System (NETPS). Numerical simulation results demonstrate the validity of the optimized UPFC controller.
Optimal design of PI/PD controller for non-minimum phase system
Authors: Wang Jie-sheng , Zhang Yong , Wang Wei
Published: February 2006

It is still an open problem to eliminate the undershoot caused by zeros in the right-half plane of non-minimum phase systems (NMPS). In this paper, a two-stage PI/PD controller is investigated on the basis of particle swarm optimization (PSO) to decrease peak overshoot, maximum undershoot, settling time and rise time of non-minimum phase (NMP) system simultaneously. PSO is a global stochastic evolutionary algorithm. It tries to find optimal regions of complex searching space through the interaction of particles in the population. The predominance of the algorithm is its excellent performance and simple implementation. Numerical simulation results illustrate the efficiency of the proposed controller compared with a genetic algorithm -simulated annealing (GA-SA) PID controller in point of improvement of performances of a step response, like fast settling time, small undershoot and small overshoot.
General fuzzified CMAC-based model reference adaptive control for ship steering using float-encoding genetic algorithm
Authors: Shen Zhipeng , Guo Chen , Li Hui
Published: February 2006

The application of CMAC control techniques for improving the performance of ship steering is discussed. Aiming at a conventional Cerebellar Model Articulation Controller (CMAC), combining CMAC-addressing schemes with a fuzzy logic idea, a general fuzzified CMAC (GFCMAC) is proposed, in which the fuzzy membership functions are utilized as the receptive field functions. Incorporating GFCMAC into a control system, a GFCMAC-based model reference adaptive controller is described, whose required teacher signals are explicitly constructed by a reference model. In order to improve the control performance, using a float-encoding genetic algorithm (FGA) to optimize parameters, an FGA-GFCMAC controller is discussed. Applying the FGA-GFCMAC controller to a ship steering control system, the simulation results show that the ship’s course can be properly controlled when changing wind and waves exist.
Multi-step predictive control with TDBP method for pneumatic position servo system
Authors: Wang Xue-Song , Cheng Yu-Hu , Sun Wei
Published: February 2006

This paper presents a new multi-step predictive controller based on neural networks and researches the adaptability of the predictive controller for a pneumatic position servo system which has some typical characteristics of non-linearity and time-varying. A diagonal recurrent neural network (DRNN) is used to predict the system output of the multi-step ahead directly. According to the intrinsic defects of a back-propagation (BP) algorithm that cannot update network weights incrementally, a new hybrid learning algorithm combining the temporal differences (TD) method with the BP algorithm to train the DRNN is put forward. A three-layer feedforward BP neural network is used as a non-linear rolling optimal controller to realize the optimization of control input of the next step according to a single-value predictive control algorithm to simplify computation. Simulation and experimental results indicate that the proposed predictive controller is suitable for real-time control of a pneumatic position servo system because of its characteristics of a simple algorithm, fast calculation of the control input and good tracking effects.
ANN-based data fusion for lumber moisture content sensors
Authors: Zhang Jiawei , Cao Jun , Zhang Dongyan
Published: February 2006

Lumber moisture content (MC) is one of the main feedback quantities of the wood drying process. Its precision directly affects the drying quality, the cost and the drying time of the wood. The measurement precision of the MC sensor is mainly affected by ambient temperature. In this paper, an artificial neural network (ANN) data fusion method is put forward to eliminate the temperature disturbance. The output of the lumber MC sensor and environmental temperature are considered inputs of the ANN. In the data fusion model, the non-linear response characteristics between the lumber MC and ambient temperature are modelled by an ANN with a back-propagation algorithm. The experimental data show that the data fusion method based on an ANN converges quickly and effectively eliminates measurement errors. The ANN automatically compensates for the changes in ambient temperature based on the network information stored in its weights. The lumber MC online measuring system realizes steady, real-time, high-accuracy measurement. The output stability was increased by 75 times compared with traditional methods, and the measuring error is within 0.8% (full scale) over a range of temperature variations from 308 to 808C.
Estimation of primary current in saturated current transformer using flexible neural network
Authors: Ge Baoming , de Almeida Aníbal T. , Ferreira Fernando J.T.E.
Published: February 2006

Current transformer saturation causes a distorted secondary current, which produces many problems in applications of protection and measurements. This paper proposes a compensating algorithm to calculate the accurate primary current by measuring the secondary current in real time. A new flexible neural network with the activation function of two changeable parameters, where the flexible neurons will flexibly change the shape of each unit to adapt its role in the learning process, is used to realize estimation of magnetizing current. This greatly simplifies the network with fewer neurons and reduces iterative learning epochs. The primary current is obtained by adding the estimated magnetizing current to the secondary current. The estimator can ensure high precision regardless of the remanent flux level and load characteristics. Data from a 900:5A current transformer are applied to train the neural network. The simulated operation in the saturated current transformer EMTP model verifies the proposed algorithm.
Implementation of an Ant Colony Optimization technique for job shop scheduling problem
Authors: Zhang Jun , Hu Xiaomin , Tan X. , Zhong J. H. , Huang Q.
Published: February 2006

Research on optimization of the job shop scheduling problem (JSP) is one of the most significant and promising areas of optimization. Instead of the traditional optimization method, this paper presents an investigation into the use of an Ant Colony System (ACS) to optimize the JSP. The main characteristics of this system are positive feedback, distributed computation, robustness and the use of a constructive greedy heuristic. In this paper, an improvement of the performance of ACS will be discussed. The numerical experiments of ACS were implemented in a small JSP. The optimized results of the ACS are favourably compared with the traditional optimization methods.
Hazards ahead?
Authors: Rose Nick
Published: March 2006

In the most radical (and politically driven) changes to the National Health Service since it was founded, the training and assessment of doctors will focus more on what they do than on what they know. The UK's lack of tools to assess doctors' performance in the workplace has caused the Postgraduate Medical Education and Training Board to turn to US workplace assessement tools developed for medical practice. These have not been designed or evaluated for application to psychiatric practice, nor do they allow for independent evaluation. It remains unclear how workplace assessment in psychiatric training will tie in with national examinations such as the Royal College of Psychiatrists' membership examination (the MRCPsych); nor is it clear whether service users are yet to have a say in such an important matter as the training of their doctors.
Real Time Optimal Guidance of Low‐Thrust Spacecraft: An Application of Nonlinear Model Predictive Control
Authors: ARRIETA‐CAMACHO JUAN JOSÉ , BIEGLER LORENZ T.
Published: March 2006

Abstract: Real time optimal guidance is considered for a class of low thrust spacecraft. In particular, nonlinear model predictive control (NMPC) is utilized for computing the optimal control actions required to transfer a spacecraft from a low Earth orbit to a mission orbit. The NMPC methodology presented is able to cope with unmodeled disturbances. The dynamics of the transfer are modeled using a set of modified equinoctial elements because they do not exhibit singularities for zero inclination and zero eccentricity. The idea behind NMPC is the repeated solution of optimal control problems; at each time step, a new control action is computed. The optimal control problem is solved using a direct method—fully discretizing the equations of motion. The large scale nonlinear program resulting from the discretization procedure is solved using IPOPT—a primal‐dual interior point algorithm. Stability and robustness characteristics of the NMPC algorithm are reviewed. A numerical example is presented that encourages further development of the proposed methodology: the transfer from low‐Earth orbit to a molniya orbit.
Displacement of the β cytoplasmic domain recovers focal adhesion formation, cytoskeletal organization and motility in swapped integrin chimeras
Authors: Partridge Michael A. , David Frank S. , Marcantonio Eugene E.
Published: March 2006

Integrin-mediated `outside-in' signaling requires the transmission of a conformational change from the extracellular domains to the cytoplasmic domains. Although one component of this conformational change is the separation of the α and β cytoplasmic domains, it is not clear how this separation could result in the initiation of downstream signals necessary for focal adhesion (FA) formation. To address this question, we used a swapped integrin heterodimer, in which the extracellular domains of the α and β chains were attached to their opposing transmembrane and cytoplasmic domains. This receptor was able to bind ligand normally, but could not promote FA formation. We then displaced the β cytoplasmic domain with either a duplication of its membrane-proximal region or an unrelated α-helical spacer. This displacement partially restored FA formation in these swapped receptors and rescued other aspects of integrin-mediated signaling, including cytoskeletal organization, motility and several tyrosine-phosphorylation-dependent signals. We suggest that separation of the cytoplasmic domains leads to alteration of the secondary structure of the distal β tail, which initiates downstream signals leading to cytoskeletal reorganization.