bluuebunny/crossref_metadata_2025 huggingface dataset:
On David Hart's The Beauty of the Infinite
Authors: Malcolm Lois E.
Published: August 2007

In “The Beauty of the Infinite,” David Hart offers a persuasive case for why the beauty of God's infinity is at the heart of the Christian evangel of peace, a peace funded by our analogical participation in God's Trinitarian life. At the heart of his argument is an appropriation of Gregory of Nyssa's concept of infinity, which presupposes a “non‐dialectical creation of out of nothing.” He then links this understanding of infinity with what he calls the “Christian evangel of peace”, which he contrasts with what he calls a “genealogy of violence” (identified with Hegel, Nietzsche, and Heidegger). His main contribution lies in his use of this understanding of God's infinity to rethink important issues in Trinitarian and Christological doctrine. Nonetheless, the question can be raised about whether his argument does justice to classically Christian understandings of the following: the presupposition, rooted in creation, of a shared human rationality, the importance of law, the centrality of the prophetic critique of idolatry and individual and corporate sin, and the place for lament in biblical depictions of Christ's death and the Christian life.
The interleukin‐6 (IL6)–174 G/C promoter genotype is associated with the presence of septic shock and the ex vivo secretion of IL6
Authors: Tischendorf J. J. W. , Yagmur E. , Scholten D. , Vidacek D. , Koch A. , Winograd R. , Gressner A. M. , Trautwein C. , Wasmuth H. E. , Lammert F.
Published: August 2007

Septic shock is associated with a high mortality and an excessive activation of immune cascades. Interleukin (IL)‐6 has been found to be a key cytokine in the pathogenesis of severe sepsis, but the importance of a regulatory polymorphism within the IL6 promoter has been controversial in these patients. The aim of the study was therefore to systematically investigate the IL6–174 G/C promoter genotype with regard to the presence of shock in patients with sepsis, the IL6 serum levels, and the ex vivo secretion of IL6, respectively. Overall, 112 consecutive subjects with severe sepsis and septic shock according to consensus criteria were enrolled. The ex vivo secretion of IL6 after stimulation with lipopolysaccharide (LPS) in a whole blood assay and the IL6 serum concentrations were determined after admission of the patients. Among the 112 subjects with severe sepsis, 85 patients fulfilled the criteria of septic shock. In these patients, the frequency of the mutated C‐allele of the IL6 promoter polymorphism was significantly (P = 0.04) higher compared to that in individuals without shock. IL6 serum concentrations were highest in patients with the GG genotype (mean 2209 pg mL−1), followed by CG genotype (mean 1113 pg mL−1), and lowest in individuals with the CC genotype (mean 256 pg mL−1). Interestingly, a significantly (P = 0.005) higher ex vivo secretion of IL6 is detected in heterozygote individuals (535 pg mL−1) and patients with the IL6 CC genotype (555 pg mL−1) compared to patients with the –174 GG genotype (276 pg mL−1). In conclusion, the IL6–174 G/C promoter genotype is associated with shock in patients with sepsis. Functionally, the mutated C‐allele is correlated with low IL6 serum concentrations, but a high ex vivo secretion after LPS stimulation. These results further indicate a complex regulation of the expression of IL6 during infection and have implications for the design of immune intervention trials.
Promoter polymorphism of IL‐18 gene in pulmonary tuberculosis in South Indian population
Authors: Harishankar M. , Selvaraj P. , Rajeswari D. N. , Anand S. P. , Narayanan P. R.
Published: August 2007

Interleukin‐18 (IL‐18) plays a vital role in both innate and acquired immunity. We analysed polymorphisms at –607(C/A) and –137(G/A) in the promoter region of IL‐18 gene by allele‐specific polymerase chain reaction in normal healthy subjects (n = 173) and patients with pulmonary tuberculosis (n = 165). Allele, genotype and haplotype frequencies did not differ significantly between normal healthy subjects and patients. The results suggest that the IL‐18 gene promoter polymorphisms are not associated with susceptibility or resistance to pulmonary tuberculosis in south Indian population of Dravidian descent.
Extensive gene conversion between CCR2 and CCR5 in domestic cat (Felis catus)
Authors: Esteves P. J. , Abrantes J. , Van Der Loo W.
Published: August 2007

Homogenization of the CC‐motif chemokine receptors CCR2 and CCR5 of cat (Felis catus) is documented and shown to be the outcome of gene conversion within the feline lineage. All regions were concerned, except the three extracellular protein domains (N‐ and C‐tails, and ECL2), suggesting that structural differentiation at these domains could be related to pathogen susceptibility.
HLA‐DPB1, ‐DRB1, and ‐DQB1 polymorphism defined in Ewenki ethnic minority of China Inner Mongolia Autonomous Region
Authors: Su X. , Bi L. , Hai R. , Qimuge S. , Ying M. , Bahring S. , Gong M.
Published: August 2007

In the present study, DNA typing for human leucocyte antigen (HLA)‐DPB1, ‐DRB1, and ‐DQB1 was performed using polymerase chain reaction–sequence‐based‐typing (PCR‐SBT) method on 94 randomly selected, healthy, unrelated individuals from the Ewenki ethnic population in Inner Mongolia Autonomous Region of China. A total of 64 alleles: 25 in DRB1, 19 in DQB1 and 20 in DPB1, were found. Among the 25 detected DRB1 alleles, DRB1*090102, DRB1*030101, DRB1*040101, DRB1*070101, and DRB1*120101/1206 were commonly observed, with frequencies of 16.0%, 13.3%, 10.1%, 7.4%, and 7.4%, respectively. The most predominant DQB1 allele was DQB1*030101/0309 with the frequency of 27.7%, followed by DQB1*0201/0202 (19.7%), DQB1*030302 (12.8%), DQB1*060101/060103 (6.4%), and DQB1*050201 (5.9%). Of the 20 detected DPB1 alleles, DPB1*020102 was the most frequent allele with the frequency of 25.5%. DPB1*0402 (21.3%), DPB1*0401 (20.2%), DPB1*0501 (10.6%) and DPB1*4101 (3.7%) were also very frequent alleles. The most frequent two‐locus haplotypes observed in the Ewenki were: DRB1*030101‐DQB1*0201/0202(10.7%), DRB1*090102‐DQB1*03032(9.8%), DRB1*070101‐DQB1*0201/0202 (5.5%), DRB1*070101‐DQB1*030302 (5.2%) and DRB1*120101/1206‐DQB1*030101/0309 (4.6%). The distribution of the HLA class II alleles and haplotypes frequencies as well as the dendrogram showed that the Ewenki population belongs to the northern group of Chinese.
Evidence for balancing selection at the DAB locus in the axolotl, Ambystoma mexicanum
Authors: Richman A. D. , Herrera G. , Reynoso V. H. , Méndez G. , Zambrano L.
Published: August 2007

The axolotl (Ambystoma mexicanum) has been characterized as immunodeficient, and the absence of major histocompatibility complex (MHC) class II polymorphism has been cited as a possible explanation. Here we present evidence for considerable allelic polymorphism at the MHC class II DAB locus for a sample of wild‐caught axolotls. Evidence that these sequences are the product of balancing selection for disease resistance is discussed.
Can Homegardens Conserve Biodiversity in Bangladesh?
Authors: Kabir Md. Enamul , Webb Edward L.
Published: August 2007

In managed landscapes, tree‐dominated habitats often show promise for biodiversity conservation. In Bangladesh where natural forest cover is less than 10 percent, homegardens, which are maintained by at least 20 millions households, represent one possible strategy for biodiversity conservation. This study investigated the floristic and structural diversity of 402 homegardens from six regions across southwestern Bangladesh. All plants were censused, totaling 419 species (59% native), including six IUCN Red Listed. The median homegarden (800 m2) contained a mean of 34 species. Each region contained a mean of 293 species in a mean of 67 homegardens. A total of 49,478 individuals (107 per homegarden and 1003 per hectare) of trees and shrubs were counted from 45.2 ha total sampled area. Thus, significant botanical richness was exhibited in the homegardens across southwestern Bangladesh. However, most species were rare: 82 percent of all species including 189 native were found in 50 or fewer homegardens, and 63 species (36 native) were found in only one or two homegardens. Sixty percent of all tree and shrub species had 50 or fewer individuals each. Thus, whereas richness across the landscape was high, serious effort must be made to increase the populations of most species. We propose three main conservation activities: (1) awareness building; (2) protection of existing individuals of rare species; and (3) propagation. Overlaying all of these activities is the inclusion of local communities in the process, who were the ones to retain these species in homegardens in the first place, and the stakeholders who will determine whether homegardens indeed act as long‐term repositories to biodiversity conservation.
Assessing Differential Step Functioning in Polytomous Items Using a Common Odds Ratio Estimator
Authors: Penfield Randall D.
Published: August 2007

Many statistics used in the assessment of differential item functioning (DIF) in polytomous items yield a single item‐level index of measurement invariance that collapses information across all response options of the polytomous item. Utilizing a single item‐level index of DIF can, however, be misleading if the magnitude or direction of the DIF changes across the steps underlying the polytomous response process. A more comprehensive approach to examining measurement invariance in polytomous item formats is to examine invariance at the level of each step of the polytomous item, a framework described in this article as differential step functioning (DSF). This article proposes a nonparametric DSF estimator that is based on the Mantel‐Haenszel common odds ratio estimator(Mantel & Haenszel, 1959),which is frequently implemented in the detection of DIF in dichotomous items. A simulation study demonstrated that when the level of DSF varied in magnitude or sign across the steps underlying the polytomous response options, the DSF‐based approach typically provided a more powerful and accurate test of measurement invariance than did corresponding item‐level DIF estimators.
Accounting for Aberrant Test Response Patterns Using Multilevel Models
Authors: Petridou Alexandra , Williams Julian
Published: August 2007

Hypotheses about aberrant test‐response behavior and hence invalid person‐measurement have hitherto included factors like ability, gender, language, test‐anxiety, and motivation, but these have not previously been collectively investigated with real data, or with multilevel models. This study analyzes the effect of these factors on person aberrance using a real mathematics assessment data set under the framework of a two‐level (person and classroom) hierarchical model. The results suggest that higher‐scoring pupils, and, to a lesser extent, second‐language learners are significantly more often aberrant. But more importantly, we find that the classroom makes a significant contribution to person aberrance and conclude that studies that investigate the sources of person aberrance with real data should model the classroom as well as individual levels.
Is It Necessary to Make Anchor Tests Mini‐Versions of the Tests Being Equated or Can Some Restrictions Be Relaxed?
Authors: Sinharay Sandip , Holland Paul W.
Published: August 2007

It is a widely held belief that anchor tests should be miniature versions (i.e., minitests), with respect to content and statistical characteristics, of the tests being equated. This article examines the foundations for this belief regarding statistical characteristics. It examines the requirement of statistical representativeness of anchor tests that are content representative. The equating performance of several types of anchor tests, including those having statistical characteristics that differ from those of the tests being equated, is examined through several simulation studies and a real data example. Anchor tests with a spread of item difficulties less than that of a total test seem to perform as well as a minitest with respect to equating bias and equating standard error. Hence, the results demonstrate that requiring an anchor test to mimic the statistical characteristics of the total test may be too restrictive and need not be optimal. As a side benefit, this article also provides a comparison of the equating performance of post‐stratification equating and chain equipercentile equating.
Life situation and daily life in a nursing home as described by nursing home residents in Sweden
Authors: Wadensten Barbro
Published: August 2007

Aims and objectives.  The overall aim of this study was to investigate nursing home residents’ opinion of their life situation in a nursing home and of their earlier life.

Background.  Few studies have focused on residents’ perception of their daily life and life situation in nursing homes.

Design.  A qualitative explorative design was used.

Methods.  Residents in a nursing home were interviewed and qualitative content analysis was performed.

Results.  The views of life residents described and how they apprehended their situation were quite different. The findings give an understanding of what it is like to live in a nursing home and show that residents apprehend their situation in very different ways. All individuals who were content with their situation in the nursing home were also content with their earlier life.

Relevance to clinical practice.  For the nurse in gerontological care, it is a challenge to get to know each resident and to provide the best nursing care and the best individual treatment for each resident. Another challenge is to help each resident find a life in the nursing home that is acceptable for him/her, and one aspect of this involves helping residents in their ageing process. The present study highlights what an important role staff have in relation with nursing home residents.
Designing a Resource Guide to help promote health in caregiving
Authors: Leenerts Mary Hobbs , Teel Cynthia S. , Shafton Gayle
Published: August 2007

Aim.  To describe development of a Resource Guide, one component of a theory‐based intervention. The Guide contains information and ideas to illuminate caregivers’ self‐care knowledge as a basis for organizing and reinforcing self‐care activities.

Background.  Inherent in the complexity of caregiving roles is the emergence of caregiving as a responsibility, often overshadowing caregiver's personal care needs. Health care professionals can partner with caregivers to promote caregiver health. Self‐Care TALK is a multimodal intervention to support this partnership.

Methods.  Two theoretical perspectives guided Resource Guide content; adult learning theory and the schema model of cognitive behavioural theory. Materials to stimulate conversations about caregivers' personal concerns about self‐care were adapted from extant literature. Sources of information were chosen based on caregivers' learning needs and images of health. Areas of development focused on content, reading level/readability, graphic design, and self‐evaluation.

Results.  The Resource Guide standardizes Self‐Care TALK protocol while personalizing caregivers' self‐care. The Resource Guide provides structure for conversations about what self‐care is and ways to promote health.

Conclusion.  The Resource Guide promotes a learning environment that complements interests and experiences of older caregivers. Use of the Guide supports and extends caregivers' self‐care vocabularies, and helps clarify self‐care schemas and health promotion.
Staff–family relationships in nursing home care: a typology of challenging behaviours
Authors: Bauer Michael
Published: August 2007

Aim. This paper draws on data from a study which investigated how Australian nursing home staff constructed staff–family relationships.

Background. Working with the family in aged care to provide the best care possible is consistent with modern nursing philosophy which espouses holistic care. The quality and enjoyment of the experience however, is frequently fraught with problems and challenges for both the staff and the family involved.

Design. A qualitative constructivist design as described by Guba and Lincoln [Fourth Generation Evaluation. Sage Publications, London.] was used.

Method. Thirty paid caregivers drawn from eight nursing homes were interviewed about their experiences of working with residents’ families. A constant comparative method of data analysis was used to arrive at the findings.

Results. This paper reports on seven themes under the category of ‘unacceptable behaviours’. These themes describe a range of attitudes and behaviours exhibited by families which staff members found undesirable.

Conclusions. Staff members found a number of family behaviours challenging. Nursing home staff perceives the family as subordinate to their needs and want to retain control of the work environment.

Relevance to clinical practice. Nursing home staff need to move away from custodial models of care focused on ‘getting the work done’ and develop more family friendly work practices that are inclusive of the needs of the family and view them as equal partners in care.
Working with volunteers: key issues for gerontological nursing – Application to practice the contribution of volunteers in a long‐term care setting: a case study
Authors: Neno Rebecca , Neno Marcus
Published: August 2007

Adopting a case study approach, this paper examines the impact of a volunteers scheme in a large Jewish care home within the UK. Good practice is articulated, opportunities and challenges identified, with specific reference to religious and cultural beliefs and the role of the volunteer coordinator is examined. The paper concludes that teamwork and the role of the volunteer coordinator is pivotal to the ongoing success of the volunteer scheme.
Evolutionary innovations of the vertebrates
Authors: KHANER Oded
Published: August 2007

This review concentrates on the greatest anatomical and morphological evolutionary innovations of the vertebrates. During evolution, many new species of vertebrates evolved and underwent modifications by developing new forms, structures and functions of tissues and organ systems. Evolutionary development of the chordates and vertebrates is herein examined in terms of innovations in their organ systems and organismal complexity. Phases during chordate and vertebrate evolutionary history with unusually high rates of increase in morphological complexity are discussed. These increases in complexity in particular chordates and vertebrates coincided with a likely genome duplication event, which resulted in a large increase in genome size and gene number in early vertebrates, and might indicate an increase in complexity. The Hox and Pax gene families are also discussed because both illustrate the relationships between organismal and molecular complexity. Most unique innovations of vertebrates caused major changes in their organismal complexity, and these changes provided new options for future evolutionary development.
Concepts, measurements and scientific problems of biocomplexity
Authors: ZHANG Zhibin
Published: August 2007

There is increasing awareness of biocomplexity as a field of study, although there are some disagreements about its definition among biologists. The science of biocomplexity has been influenced greatly by the emergence of the science of complexity, which aims to solve complicated problems in complex systems. In this paper, I review the basic concepts and scientific problems of biocomplexity. I argue that biological systems are adaptive complex systems that tend to become more complicated over time. I hypothesize that complexity is favored by natural selection. There are two relatively independent evolutionary templates for complexity in biological systems: gene‐guided and neural‐guided systems. In general, biology has been overly influenced by gene‐dominant evolution theory, which cannot account for the complex behaviors, social structures, and ecosystems that exist. Sustained energy intake, non‐polynomial (NP)‐hard problems and stability (e.g. thermodynamic, non‐linear and evolutionary stability) are probably the three most important properties of biological systems. Total work is not equivalent to the energy input (non‐equivalence rule) in biological systems because the input energy is re‐used. The total work can be measured using the order energy (ordergy), a function of energy input and the efficiency of energy transformation. Hierarchy may be essential in solving NP‐hard problems and in reducing the instability of non‐linearity in biological systems.
Warfarin anticoagulation intensity in specialist‐based and in computer‐assisted dosing practice
Authors: ONUNDARSON P. T. , EINARSDOTTIR K. A. , GUDMUNDSDOTTIR B. R.
Published: August 2007

The efficacy and safety of oral anticoagulation (OA) with vitamin K antagonists depends on maintaining anticoagulation intensity, measured as international normalized ratio (INR), within defined target ranges. We assessed the quality of our current software‐assisted warfarin dosing in the year 2006 in 941 unselected consecutive patients on stable OA with atrial fibrillation (AF), venous thromboembolism (VTE) and prosthetic heart valves (PHV) by comparing it to our previous cardiologist‐based dosing practice in 1992 when a study was carried out on 241 comparable patients. Over 14 years, the time within target range increased in all three anticoagulated groups, i.e. in AF patients from 46% to 81%, in VTE patients from 62% to 84% and in patients with PHV from 40% to 64%. Only 1% of the treatment time is now spent at INR < 1.5 compared to 7% previously (P < 0.0001) and 0.4% of the treatment time at INR > 4.0 presently compared to 2.8% in the past (P < 0.0001). INR‐targets are better achieved with the current software‐assisted dosing practice and extreme low and high values are less common than previously. The results provide indirect evidence suggesting that both efficacy and safety has improved with the current practice.
Adolescents’ intentions to offer assistance to friends with depression or conduct disorder: associations with psychopathology and psychosocial characteristics
Authors: Kelly Claire M. , Jorm Anthony F.
Published: August 2007

Aim:  To describe adolescents’ intentions to offer assistance to friends experiencing mental health problems and the associations with the adolescent’s own psychopathology and psychosocial characteristics.

Method:  A survey study of 1143 students aged 12–17 years in schools in the Australian Capital Territory and South Australia. Respondents were given a vignette of a young person with either depression or conduct disorder and asked questions about how they would respond to a friend with the problem presented. First‐aid responses were classified as social support, adult engagement and unhelpful responses. Adolescent psychopathology was measured with the Strengths and Difficulties Questionnaire and desired social distance with a six‐item scale.

Results:  The main response was to offer social support such as listening to the friend, distracting them or offering advice. Low confidence in offering help and unhelpful responses were associated with higher desired social distance, male gender, conduct problems and poor social skills. Providing social support was associated with female gender, high prosocial scores and lower desired social distance. Adult engagement to help a peer with conduct disorder was associated with female gender.

Conclusion:  Future education about mental health that is aimed at this age group should take into consideration the preferences of young people to seek help from their peers, and focus on encouraging young people to seek adult assistance when they are worried about the well‐being of a friend.
Comorbid depressive symptoms in the developmental course of adolescent‐onset psychosis
Authors: Myles‐Worsley Marina , Weaver Starla , Blailes Francisca
Published: August 2007

Aim:  Depressive symptoms are common in the early prodromal phase of schizophrenia and other psychotic disorders. The objectives of the present study were to retrospectively examine the severity of depressive symptoms and their relationship to positive symptoms over the developmental course of adolescent‐onset psychosis (AO‐PSY).

Methods:  The subjects were 62 unmedicated adolescents with DSM‐IV psychosis and 104 normal controls from a Pacific island isolate with an elevated prevalence of schizophrenia. We used a modified K‐SADS‐PL to assess adolescents for a full range of Axis I psychopathology and quantified severity of depressive and positive symptoms over the adolescent’s lifespan.

Results:  Among AO‐PSY subjects, 84% reported abnormal levels of depressive symptoms with mean onset 1.3 years prior to transition to psychosis. In 60% of the AO‐PSY subjects with depressive symptoms, positive symptoms began first. A continuous linear increase in depressive symptom severity over the developmental course of illness mirrored the steady rise in positive symptom severity as psychosis emerged.

Conclusions:  We found that it is typically a combination of positive symptoms and depressive symptoms building in parallel that leads from the prodrome to frank psychosis. These results suggest that depressive symptoms represent more of an integral component of disease progression than an independent risk factor that predicts transition to early onset psychosis.
An Early Intervention in Psychosis Service for adolescents
Authors: Tiffin Paul A. , Hudson Suzanne
Published: August 2007

Aims:  To describe a service operating in Teesside, England, that provides early intervention for young people aged 14–18 years at high risk of, or affected by psychotic illness.

Methods:  The Service Delivery Model for evaluating and managing young people referred to the service is described. In addition, data routinely collected as part of performance management are presented.

Results:  During 2006 42 young people were referred to the service of which 29 were accepted. At the end of 2006 the team active caseload was 22 patients.

Conclusion:  An ‘adolescent‐specific’ team as part of a 14–35 Early Intervention Service appears to be a feasible and sustainable development and may confer advantages over less age‐orientated care.
On the Edge: a drama‐based mental health education programme on early psychosis for schools
Authors: Roberts Glenn , Somers John , Dawe Jocelyn , Passy Rowena , Mays Carly , Carr Graham , Shiers David , Smith Jo
Published: August 2007

Aims:  On the Edge is a mental health education programme designed to support early intervention by increasing knowledge and understanding of early psychosis, reducing the stigma associated with mental health issues and improving awareness of avenues of help. The target audience was young people aged 14–22 years in schools and colleges.

Methods:  An interactive drama programme was developed through collaborative working across psychiatry, applied drama and those with direct experience of psychosis. A national tour engaged 2500 students in 71 performances that took place in 51 schools and colleges. The programme was evaluated against its aims with data collected both during and after the tour.

Results:  Quantitative and qualitative evaluation found significant gains with respect to all three aims. Thirty‐one schools developed supportive links with local mental health services.

Conclusions:  This programme shows the value and effectiveness of delivering health education on early psychosis through the medium of applied drama, and offers a model for a programme that can be incorporated into early intervention services. Lessons learned through delivering this programme are a valuable contribution towards future developments of mental health education programmes for schools.
The First‐Episode Psychosis Outcome Study: premorbid and baseline characteristics of an epidemiological cohort of 661 first‐episode psychosis patients
Authors: Conus Philippe , Cotton Sue , Schimmelmann Benno Graf , McGorry Patrick D. , Lambert Martin
Published: August 2007

Aims:  Studies conducted in first‐episode psychosis (FEP) samples avoid many biases. However, very few studies are based on epidemiological cohorts treated in specialized FEP services. The aim of this file audit study was to examine premorbid and baseline characteristics of a large epidemiological sample of FEP.

Methods:  File audit study of all patients admitted to the Early Psychosis Prevention and Intervention Centre between 1998 and 2000 using a specialized questionnaire.

Results:  There were 661 patient files included in the study. Premorbid evaluation revealed high rates of substance use disorder (74.1%), history of psychiatric disorder (47.5%), past traumatic events (82.7%) suicide attempts (14.3%) and family history of psychiatric illness (55.6%). Baseline characteristics revealed high intensity of illness (mean CGI 5.5), high prevalence of lack of insight (62%) and high rate of comorbidity (70%).

Conclusion:  High rates of traumatic events or episodes of mental illness before treatment for FEP must be considered when designing treatment approaches because a too narrow focus on positive psychotic symptoms will inevitably lead to incomplete treatment. Additionally, early intervention programmes need sufficient range of resources to address the multiple challenges presented by FEP patients such as high severity of illness, comorbidities and functional impairment. Finally, observation of an important degree of functional impairment despite short duration of untreated psychosis suggests that while early detection of FEP is a necessary step in early intervention, it may not be sufficient to improve functional recovery in psychosis and that efforts aimed at identifying people during the prodromal phase of psychotic disorders should be pursued.
When things are not as they seem: detecting first‐episode psychosis upon referral to ultra high risk (‘prodromal’) clinics
Authors: Nelson Barnaby , Yung Alison R.
Published: August 2007

The current paper examines a neglected function of ‘ultra high risk’ (UHR) clinics: to detect first‐episode psychosis (FEP) mistakenly identified as a prodrome. A clinical audit was conducted of referrals to a UHR service, the Personal Assessment and Crisis Evaluation Clinic, over a 12‐month period (April 2005–March 2006). In this audit, 11.4% of the total number of referrals (n= 149) and 11.9% of those who attended a first appointment were psychotic on referral. These figures indicate that a substantial proportion of individuals thought to be prodromal are in fact suffering FEP. UHR clinics minimize duration of untreated psychosis for FEP patients mistaken as prodromal.
Hydrologic Model Framework for Water Resources Planning in the Santa Cruz River, Southern Arizona1
Authors: Shamir Eylon , Meko David M. , Graham Nicholas E. , Georgakakos Konstantine P.
Published: August 2007

Abstract:  The authors develop a model framework that includes a set of hydrologic modules as a water resources management and planning tool for the upper Santa Cruz River near the Mexican border, Southern Arizona. The modules consist of: (1) stochastic generation of hourly precipitation scenarios that maintain the characteristics and variability of a 45‐year hourly precipitation record from a nearby rain gauge; (2) conceptual transformation of generated precipitation into daily streamflow using varied infiltration rates and estimates of the basin antecedent moisture conditions; and (3) surface‐water to ground‐water interaction for four downstream microbasins that accounts for alluvial ground‐water recharge, and ET and pumping losses. To maintain the large inter‐annual variability of streamflow as prevails in Southern Arizona, the model framework is constructed to produce three types of seasonal winter and summer categories of streamflow (i.e., wet, medium, or dry). Long‐term (i.e., 100 years) realizations (ensembles) are generated by the above described model framework that reflects two different regimes of inter annual variability. The first regime is that of the historic streamflow gauge record. The second regime is that of the tree ring reconstructed precipitation, which was derived for the study location. Generated flow ensembles for these two regimes are used to evaluate the risk that the regional four ground‐water microbasins decline below a preset storage threshold under different operational water utilization scenarios.
Application of the Indicators of Hydrologic Alteration Software in Environmental Flow Setting1
Authors: Mathews Ruth , Richter Brian D.
Published: August 2007

Abstract:  River scientists are increasingly asked to provide recommendations about the amount and timing of water flows needed to support ecosystem health. The need for scientifically credible environmental flow assessments and the limited availability of resources to conduct in‐depth studies place a premium on methods that can be readily applied at low cost. The Indicators of Hydrologic Alteration (IHA) software program was originally developed by The Nature Conservancy in the 1990s to quickly process daily hydrologic records to enable characterization of natural water conditions and facilitate evaluations of human‐induced changes to flow regimes. The evolution of the IHA software is discussed, including recent revisions and additions to the IHA that have improved its utility in environmental flow‐setting processes. Drawing from holistic methodologies developed around the world, the ability to calculate characteristics of five components of flow important to river ecosystem health – extreme low flows, low flows, high‐flow pulses, small floods and large floods – has been added to the IHA. A practical advantage of these environmental flow components is that an environmental flow prescription based upon them can be readily implemented in most water management settings. Frequently used as a one‐time generator of flow statistics, the value of the IHA increases when used interactively with ecological models. A process for linking IHA output to an ecological model to explore flow‐ecology relationships within an adaptive management context is presented and demonstrated through its application on the Green River, Washington. The IHA used in conjunction with ecological models facilitates the creation and testing of flow‐ecology hypotheses, formulation of water and land protection or restoration goals, and development of a focused research and monitoring program, all important components of environmental flow‐setting processes.
Influence of adapting speed on speed and contrast coding in the primary visual cortex of the cat
Authors: Hietanen M. A. , Crowder N. A. , Price N. S. C. , Ibbotson M. R.
Published: August 2007

Adaptation is a ubiquitous property of the visual system. Adaptation often improves the ability to discriminate between stimuli and increases the operating range of the system, but is also associated with a reduced ability to veridically code stimulus attributes. Adaptation to luminance levels, contrast, orientation, direction and spatial frequency has been studied extensively, but knowledge about adaptation to image speed is less well understood. Here we examined how the speed tuning of neurons in cat primary visual cortex was altered after adaptation to speeds that were slow, optimal, or fast relative to each neuron's speed response function. We found that the preferred speed (defined as the speed eliciting the peak firing rate) of the neurons following adaptation was dependent on the speed at which they were adapted. At the population level cells showed decreases in preferred speed following adaptation to speeds at or above the non‐adapted speed, but the preferred speed did not change following adaptation to speeds lower than the non‐adapted peak. Almost all cells showed response gain control (reductions in absolute firing capacity) following speed adaptation. We also investigated the speed dependence of contrast adaptation and found that most cells showed contrast gain control (rightward shifts of their contrast response functions) and response gain control following adaptation at any speed. We conclude that contrast adaptation may produce the response gain control associated with speed adaptation, but shifts in preferred speed require an additional level of processing beyond contrast adaptation. A simple model is presented that is able to capture most of the findings.
Ca2+‐dependent ATP release from A549 cells involves synergistic autocrine stimulation by coreleased uridine nucleotides
Authors: Tatur Sabina , Groulx Nicolas , Orlov Sergei N. , Grygorczyk Ryszard
Published: August 2007

Extracellular ATP is a potent surfactant secretagogue but its origin in the alveolus, its mechanism(s) of release and its regulatory pathways remain unknown. Previously, we showed that hypotonic swelling of alveolar A549 cells induces Ca2+‐dependent secretion of several adenosine and uridine nucleotides, implicating regulated exocytosis. In this study, we examined sources of Ca2+ for the elevation of intracellular Ca2+ concentration ([Ca2+]i) evoked by acute 50% hypotonic stress and the role of autocrine purinergic signalling in Ca2+‐dependent ATP release. We found that ATP release does not directly involve Ca2+ influx from extracellular spaces, but depends entirely on Ca2+ mobilization from intracellular stores. The [Ca2+]i response consisted of slowly rising elevation, representing mobilization from thapsigargin (TG)‐insensitive stores and a superimposed rapid spike due to Ca2+ release from TG‐sensitive endoplasmic reticulum (ER) Ca2+ stores. The latter could be abolished by hydrolysis of extracellular triphospho‐ and diphosphonucleotides with apyrase; blocking P2Y2/P2Y6 receptors of A549 cells with suramin; blocking UDP receptors (P2Y6) with pyridoxal phosphate 6‐azophenyl‐2′,4′‐disulfonic acid (PPADS); emptying TG‐sensitive stores downstream with TG or caffeine in Ca2+‐free extracellular solution; or blocking the Ca2+‐release inositol 1,4,5‐triphosphate receptor channel of the ER with 2‐aminoethyldiphenylborinate. These data demonstrate that the rapid [Ca2+]i spike results from the autocrine stimulation of IP3/Ca2+‐coupled P2Y, predominantly P2Y6, receptors, accounting for ∼70% of total Ca2+‐dependent ATP release evoked by hypotonic shock. Our study reveals a novel paradigm in which stress‐induced ATP release from alveolar cells is amplified by the synergistic autocrine/paracrine action of coreleased uridine and adenosine nucleotides. We suggest that a similar mechanism of purinergic signal propagation operates in other cell types.
The nature of corticospinal paths driving human motoneurones during voluntary contractions
Authors: Butler Jane E. , Larsen Thomas S. , Gandevia Simon C. , Petersen Nicolas T.
Published: August 2007

The properties of the human motor cortex can be studied non‐invasively using transcranial magnetic stimulation (TMS). Stimulation at high intensity excites corticospinal cells with fast conducting axons that make direct connections to motoneurones of human upper limb muscles, while low‐intensity stimulation can suppress ongoing EMG. To assess whether these cells are used in normal voluntary contractions, we used TMS at very low intensities to suppress the firing of single motor units in biceps brachii (n= 14) and first dorsal interosseous (FDI, n= 6). Their discharge was recorded with intramuscular electrodes and cortical stimulation was delivered at multiple intensities at appropriate times during sustained voluntary firing at ∼10 Hz. For biceps, high‐intensity stimulation produced facilitation at 17.1 ± 2.1 ms (lasting 2.4 ± 0.9 ms), while low‐intensity stimulation (below motor threshold) produced suppression (without facilitation) at 20.2 ± 2.1 ms (lasting 7.6 ± 2.2 ms). For FDI, high‐intensity stimulation produced facilitation at 23.3 ± 1.2 ms (lasting 1.8 ± 0.4 ms), with suppression produced by low‐intensity stimulation at 25.2 ± 2.6 ms (lasting 7.5 ± 2.6 ms). The difference between the onsets of facilitation and suppression was short: 3.1 ± 1.2 ms for biceps and 2.0 ± 1.5 ms for FDI. This latency difference is much less than that previously reported using surface EMG recordings (∼10 ms). These data suggest that low‐intensity cortical stimulation inhibits ongoing activity in fast‐conducting corticospinal axons through an oligosynaptic (possibly disynaptic) path, and that this activity is normally contributing to drive the motoneurones during voluntary contractions.
A critical role of the cAMP sensor Epac in switching protein kinase signalling in prostaglandin E2‐induced potentiation of P2X3 receptor currents in inflamed rats
Authors: Wang Congying , Gu Yanping , Li Guang‐Wen , Huang Li‐Yen Mae
Published: August 2007

Sensitization of purinergic P2X receptors is one of the mechanisms responsible for exaggerated pain responses to inflammatory injuries. Prostaglandin E2 (PGE2), produced by inflamed tissues, is known to contribute to abnormal pain states. In a previous study, we showed that PGE2 increases fast inactivating ATP currents that are mediated by homomeric P2X3 receptors in dorsal root ganglion (DRG) neurons isolated from normal rats. Protein kinase A (PKA) is the signalling pathway used by PGE2. Little is known about the action of PGE2 on ATP currents after inflammation, although the information is crucial for understanding the mechanisms underlying inflammation‐induced sensitization of P2X receptors. We therefore studied the effects of PGE2 on P2X3 receptor‐mediated ATP currents in DRG neurons dissociated from complete Freund's adjuvant (CFA)‐induced inflamed rats. We found that PGE2 produces a large increase in ATP currents. PKCɛ, in addition to PKA, becomes involved in the modulatory action of PGE2. Thus, PGE2 signalling switches from a solely PKA‐dependent pathway under normal conditions to both PKA‐ and PKC‐dependent pathways after inflammation. Studying the mechanisms underlying the switch, we demonstrated that cAMP‐responsive guanine nucleotide exchange factor 1 (Epac1) is up‐regulated after inflammation. The Epac agonist CPT‐OMe mimics the potentiating effect of PGE2 and occludes the PKC‐mediated PGE2 action on ATP currents. These results suggest that Epac plays a critical role in P2X3 sensitization by activation of de novo PKC‐dependent signalling of PGE2 after inflammation and would be a useful therapeutic target for pain therapies.
Thrombospondin‐1 expression and localization in the developing ovine lung
Authors: Sozo Foula , Hooper Stuart B. , Wallace Megan J.
Published: August 2007

Fetal lung growth is critically dependent on the degree to which the lungs are expanded by liquid, although the mechanisms involved are unknown. As thrombospondin‐1 (TSP‐1) can regulate cell proliferation, attachment, spreading and angiogenesis, we investigated the effects of alterations in fetal lung expansion on TSP‐1 expression in sheep. TSP‐1 mRNA levels were investigated using Northern blot analysis and in situ hybridization, whereas the protein levels were determined by immunohistochemistry. Early growth response 1 (EGR1) mRNA levels were measured by quantitative real‐time PCR. TSP‐1 was expressed in type‐II alveolar epithelial cells and fibroblasts and its mRNA levels increased from 100.0 ± 14.0% in control fetuses to 347.5 ± 73.6% at 36 h of increased lung expansion (P < 0.05), and were reduced to 39.4 ± 6.1% of control levels (100.0 ± 20.4%) at 20 days of decreased lung expansion (P < 0.05). The percentage of cells positive for TSP‐1 mRNA increased from 1.9 ± 0.4% to 5.2 ± 0.8% at 36 h of increased fetal lung expansion (P < 0.01). The proportion of tissue stained positive for TSP‐1 protein doubled at 36 h of increased lung expansion (23.3 ± 2.2%) compared to controls (11.7 ± 3.2%; P < 0.05). Conversely, at 20 days of decreased lung expansion, the percentage of tissue that stained positive for TSP‐1 was halved (25.7 ± 3.2%) compared to controls (39.8 ± 3.3%; P < 0.05). The increase in TSP‐1 expression may be due to increased mRNA levels of the transcription factor EGR1 at 36 h of increased lung expansion (2.7 ± 0.7‐fold of control levels (1.0 ± 0.2); P < 0.05). Given the known functions of TSP‐1 and its localization within the lung, we speculate that TSP‐1 may have a significant role in regulating fetal lung growth.
Responses evoked in single sympathetic nerve fibres of the rat tail artery by systemic hypoxia are dependent on core temperature
Authors: Johnson Christopher , Hudson Steven , Marshall Janice
Published: August 2007

No direct evidence exists of the changes evoked by systemic hypoxia in sympathetic nerves to the rat cutaneous circulation, and of the concomitant changes in cutaneous blood flow. Here we investigated responses evoked by two levels of systemic hypoxia (12% and 8% inspired O2) in single sympathetic units supplying tail caudal ventral artery (CVA) in spontaneously breathing anaesthetized rats, whilst simultaneously recording tail blood flow and vascular resistance (TVR) from the CVA, under conditions of modest hypothermia and hyperthermia. During modest hypothermia and normoxia, TVR was high and CVA unit activity was present, with marked respiratory modulation and a rhythmictiy (T‐rhythm) that was often independent of respiration. Hypoxia evoked a graded fall in TVR indicating vasodilatation, but there were no consistent changes in CVA unit firing rate or T‐rhythm frequency, although respiratory modulation increased. By contrast, during hyperthermia, TVR was low and CVA unit activity was absent. Systemic hypoxia evoked graded increases in TVR, indicating vasoconstriction, and in 8% O2 there was recommencement of firing in some CVA units, at low discharge rate, with respiratory modulation but no T‐rhythm. These results indicate that the changes evoked by systemic hypoxia in TVR and sympathetic nerve activity to CVA are dependent on core temperature. During modest hypothermia, hypoxia‐induced cutaneous vasodilatation in the tail is independent of sympathetic activity, whereas during hyperthermia, when sympathetic activity is ‘switched off’, severe hypoxia initiates respiratory‐related low level activity, causing cutaneous vasoconstriction.
Muscle fatigue: what, why and how it influences muscle function
Authors: Enoka Roger M. , Duchateau Jacques
Published: August 2007

Much is known about the physiological impairments that can cause muscle fatigue. It is known that fatigue can be caused by many different mechanisms, ranging from the accumulation of metabolites within muscle fibres to the generation of an inadequate motor command in the motor cortex, and that there is no global mechanism responsible for muscle fatigue. Rather, the mechanisms that cause fatigue are specific to the task being performed. The development of muscle fatigue is typically quantified as a decline in the maximal force or power capacity of muscle, which means that submaximal contractions can be sustained after the onset of muscle fatigue. There is even evidence that the duration of some sustained tasks is not limited by fatigue of the principal muscles. Here we review experimental approaches that focus on identifying the mechanisms that limit task failure rather than those that cause muscle fatigue. Selected comparisons of tasks, groups of individuals and interventions with the task‐failure approach can provide insight into the rate‐limiting adjustments that constrain muscle function during fatiguing contractions.