bluuebunny/crossref_metadata_2025 huggingface dataset:
Nurses' representations of the positive and negative features of nursing
Authors: Lawrence Jeanette A , Wearing Alexander J , Dodds Agnes E
Published: November 2003

Nurses ‘representations of their work are defined as their cognitive ‘work spaces’, a theoretical concept derived from Newell & Simon's (1977) problem‐solving model and Lewin's (1935) concept of interacting positive and negative valences Using a structural equation modelling technique, a network of positive and negative features in nurses ‘work spaces is described in patterns of response to a questionnaire eliciting nurses’ ratings of their professional opportunities and difficulties The modelling technique revealed the dominance of positive over negative features, and the overall significance of social recognition for encouraging nurses to remain in nursing Comparative analyses revealed that dominant features of work space representations did not differ for nurses from four city and country hospitals, nor in relation to positions in the nursing hierarchy The importance of understanding the perceptions of nurses is discussed in relation to changes and development in nursing as a profession
Job satisfaction and organizational characteristics: results of a nationwide survey of baccalaureate nursing faculty in the United States
Authors: Snarr Carol E , Krochalk Pamela C
Published: November 2003

This study examines the relationship between job satisfaction of nursing faculty and the organizational characteristics of the institutions and nursing programmes in which they teach A stratified random sample of 48 baccalaureate nursing programmes throughout the United States was selected for the study, of which 25 (52%) of the programme deans agreed to participate Two questionnaires were used in data collection (a) The Job Descriptive Index (Revised), which was sent to 576 nursing faculty at the participating programmes, resulting in 327 (57%) usable questionnaires, and (b) The Organizational Characteristics Questionnaire which was completed by the nursing programmes deans Dimensions of job satisfaction measured were work on present job, present pay, opportunities for promotion, supervision, coworkers and job in general The organizational characteristics examined were institutional control (public, private), size (student enrolment), nursing degrees offered, programmes offered (undergraduate, graduate), number of nursing faculty, number of nursing students, budget, tenure and salary Although nursing faculty tended to be satisfied with their jobs, correlation and multiple regression analyses indicated weak to negligible relationships between job satisfaction and the organizational characteristics examined Further study of the dimensions of job satisfaction within the academic environment is needed to understand the complexity of these relationships fully
Living a caring presence in nursing: a Heideggerian hermeneutical analysis
Authors: Nelms Tommie P
Published: November 2003

While the claim has been made that caring is the most important, central focus of nursing, often the meaning of caring presence in nursing and human caring in general is so deeply embedded in our consciousness and our cultural practices that its presence is invisible or taken for granted The purpose of this Heideggerian hermeneutical study was to illuminate nurses' shared practices and common meanings of living a caring presence in nursing Five nurses wrote a story, one they would never forget, of living a caring presence The stones were analysed and interpreted against a background of Heideggerian philosophy to reveal the constitutive pattern, ‘caring as the presencing of being’ Meaning and complexity of the pattern were revealed in themes that illuminate and articulate the essence of nursing and the phenomenon of caring Themes were the timelessness and spacelessness of caring, creating home, and the call to care as the call of conscience The results can help to answer the Heideggerian question of what a marginalized cultural practice like the profession of nursing can teach a levelling technological society about the meaning of being
Effects of critical care unit noise on the subjective quality of sleep
Authors: Topf Margaret , Bookman Margaret , Arand Donna
Published: November 2003

Nurse researchers have provided evidence that hospital critical care unit (CCU) noise may put patients at risk for sleep problems Technological advances in this setting have been described as contributing to this problem Although data on the negative effects of CCU noise on physiological sleep are available, less attention has been given to self‐reports of the subjective quality of sleep following exposure to this stressor This study hypothesized that subjects exposed to CCU sound levels would report poorer subjective sleep than subjects in a quieter environment Sixty female subjects, attempting to sleep overnight in a laboratory, were randomly assigned to an experimental group, where they heard an audiotape recording of CCU sounds throughout the night, or to a quiet group where the audiotape recording of CCU sounds was withheld A self‐rating questionnaire was used to assess subjective sleep The noise condition subjects reported taking longer to fall asleep, less tune sleeping, more awakenings, poorer quality of sleep compared to home, as well as fewer positive and more negative adjectives descriptive of sleep Self‐reports of the time spent sleeping and the number of negative adjectives descriptive of sleep yielded the greatest number of significant correlations with scores for the other measures of sleep, indicating that these measures may be more accurate Data on the quality of dreams yielded no difference between groups The results provide support for the hypothesis that CCU sound levels impact negatively on subjective sleep It was recommended, now that CCU sound levels were isolated in the laboratory as a potential stressor, that future research should attempt to replicate this study in a hospital CCU
How not to clarify concepts in nursing
Authors: Paley John
Published: November 2003

Concept analysis and conceptual clarification form an identifiable genre within the nursing literature, with most recent examples drawing on the model proposed by Walker & Avant (1988) This paper argues that the Walker & Avant model is based on untenable assumptions, and that the writings of those who adopt it inevitably contain a serious flaw that vitiates the procedure and renders the results arbitrary In particular, the relationship between concept and theory, a topic to which the philosophy of science has devoted much attention, has been misunderstood by these authors Concepts are not the ‘building blocks’ of theory, but the niches created by theory, and any ‘conceptual clarification’ that anticipates theoretical commitment becomes a vacuous exercise in semantics
The politics of phenomenological concepts in nursing
Authors: Holmes Colin A
Published: November 2003

This paper challenges those nurses who champion Heideggerian phenomenology, by outlining some of the possible political consequences of that philosophy Some relationships between phenomenology and fascism are discussed, with special reference to anti‐humanism and authenticity Heidegger's commitment to Nazism is affirmed and, following the lead of other recent contributions to the debate, it is suggested that this was the likely, if not inevitable, result of his phenomenological philosophy It is concluded that, because of its immanent fascism, Heideggerian phenomenology is at odds with the general value orientation publicly espoused by the nursing profession, and that this may render it not only unsuitable as a means of understanding and elaborating nursing knowledge, but also actively counter‐productive to the conventional aspirations of nurses
CINAHL: an exploratory analysis of the current status of nursing theory construction as reflected by the electronic domain
Authors: Riddlesperger Kristina L , Beard Margaret , Hisley Shelton McLendon , Flowers Deborah L , Pfeifer Karen A , Stiller Janeth J
Published: November 2003

Since the 1980s the electronic domain has become the primary method for academic and professional communication of research and information Papers relating to theory construction in nursing are a frequently occurring phenomenon within the electronic domain Theory construction provides the underpinning for the advancement of professional nursing, facilitating the conceptualization of nursing actions leading to theory‐based practice and research The purpose of this study was to address the research question, ‘What are the similarities and differences among theory construction papers that are accessible electronically in nursing literature today’ The Cumulative Index to Nursing and Allied Health Literature (CINAHL) was accessed to obtain a listing of papers from which an overall description of the type of theory construction papers being published in the nursing literature today could be determined A literature search was conducted using the description 'theory construction. Papers were limited to publication years from 1990 onwards. A total of 125 papers were obtained and read by one of the six authors Using grounded theory, categories emerged by identification of similarities and differences among the papers The findings are discussed here along with suggestions for further study. A second purpose of this paper was to present both traditional and non‐traditional methods of tapping into the electronic domain when searching for assistance with theory construction
Concerns of nurse educators regarding the implementation of a major curriculum reform
Authors: Gwele Nomthandazo S
Published: November 2003

This comparative descriptive study used the self‐administered stages of concern questionnaire, a diagnostic dimension of the Concerns Based Adoption Model, to measure the stages of concern of nurse educators (n= 93) at four nursing colleges regarding implementation of a new comprehensive basic nursing programme (CBNP) Data were analysed using the guidelines from the manual designed by Hall et al The MANOVA was used to measure variations between colleges in high and low stages of concern by (a) timing of adoption, (b) perceived level of experience with the CBNP and (c) training in use Differences between colleges in timing of adoption were significant in intensity of lower stages of concern (awareness, informational, personal and management) only Concerns of inexperienced users were significantly higher than those of experienced users on both lower and higher stages of concern Training in teaching a comprehensive basic nursing programme failed to effect significant differences in intensity of concerns among nurse educators
Community development: theoretical and practical issues for community health nursing in Canada
Authors: Chalmers Karen I , Bramadat Ina J
Published: November 2003

Despite the importance currently given to community development as an increasingly significant role for community nurses, there is little analysis of the role in the nursing literature This paper provides background information on the historical origins of community development work through an extensive review of the literature As well, four models of community development are synthesised from literature in sociology, social psychology, education and political science These include economic development models, education models both formal and informal, confrontational models, and empowerment models Each is discussed, and the relevance for community health nursing practice is critiqued Finally, issues which may arise when community health nurses attempt to practice within a community development model are discussed Issues are examined related to the structures of organizations in which nurses work, characteristics of nurses themselves, and the communities which nurses serve The argument is advanced that despite the pitfalls and problems, this new role shows promise as an important mechanism for community health nurses to promote the community's health However, much additional work will be needed to test out models for community development in actual practice Evaluation of the role will also be important to determine the degree to which it can be implemented and the resultant health outcomes for the population
The first year as a staff nurse: the experiences of a first cohort of Project 2000 nurses in a demonstration district
Authors: Jasper Melanie
Published: November 2003

This paper describes the experiences of eight staff nurses who were students in the first cohort of a Project 2000 course in a pilot district during their post–qualification year A qualitative approach, informed by phenomenological methodology, was adopted in order to present these experiences alongside the meaning attributed to them by the nurses Taped, focused group discussions, using semi‐structured interviews, were analysed This yielded five themes which describe the structure of these experiences from‘coming out of school' through to the acknowledgement and confidence in themselves as a different kind of nurse to those trained on previous traditional courses The findings suggest that the vision of the United Kingdom Central Council in proposing Project 2000 courses is likely to be realized These nurses had gained the competent technical and clinical skills expected of any nurse However, they also displayed skills previously absent in newly–qualified nurses, such as evidence of analytical decision–making and confident interpersonal skills, which are likely to enable them to take an equal place amongst other members of the multindash;professional team in the future Although competent practitioners, the process they had undergone to reach this had, at times, been traumatic The implications arising from the study are that more attention needs to be paid to the personal and professional development needs of Project 2000 nurses, both at the end of the course and in their first post‐qualifying year
The important attributes of a nurse from the perspective of qualified and student nurses
Authors: March Paul L , McPherson Anne
Published: November 2003

The studies described here set out to discover what student and qualified nurses understand to be the important attributes of a nurse The first study was exploratory and used a repertory grid technique to ask 72 students, qualified nurses and nurse lecturers to compare themselves (as a nurse) with a number of other nurses and carers of their own choosing The constructs that the participants used to make these comparisons were then categorized into attributes Those attributes that had been used by more than 10% of any of the subgroups were used in the second study as the basis of a questionnaire in which nurses were asked to put these categories in order of importance The questionnaire was completed by 565 qualified and student nurses The responses showed a remarkable level of agreement between nurses, irrespective of rank or student status The only attribute over which there were large differences was intelligence The study provides strong evidence that the view of the important attributes of a nurse remain unchanged right across the nursing profession, and the discovery of these attributes has important implications for nurse selection and training
Postgraduate education expectations: a survey of Hong Kong graduate nurses
Authors: Simsen Barbara J , Holroyd Eleanor , Selhck Kenneth
Published: November 2003

Tertiary education for nurses in Hong Kong is in its early development With many overseas universities competing to secure Asian students, the need for locally developed programmes to meet Hong Kong's needs can be overlooked In this survey 705 nurses with degree level qualifications working for the major public and private employing agencies completed a questionnaire designed to obtain details of postgraduate study plans and preferences for the type, focus and mode of postgraduate programmes Analysis of responses showed 50% of the graduates surveyed intended to pursue further study in the next two years with a clear preference for course work masters, degree programmes (55%), studies with a specialist (71%) rather than a generahst focus, and programmes offered locally (85%) on a part‐time basis (86%) Future educational needs were also found to vary according to gender, marital status, place of employment and nursing post The findings from this survey have considerable implications for educational and professional nursing developments and planning to meet the future health care needs of Hong Kong In addition, the information may inform the planning of other countries newly embarked on tertiary education for nurses
The quality of intraoperative nursing care: the patient's perspective
Authors: Leinonen Tuija , Leino‐Kilpi Helena , Jouko Katajisto
Published: November 2003

The purpose of this study was to document patients' responses (n = 246) to intraoperative care and to find out whether or not their opinions (n = 158) changed with time Another goal was to develop a patient‐based scale for continuous systematic evaluation The data were collected by a structured questionnaire in two phases in 1993 first at the end of the patients' hospital stay, and then after a few weeks at home The following themes were covered in the questionnaire biological‐physiological, experiential, cognitive, functional, ethical, the characteristics and competence of nursing professionals, and environmental Statistical analysis suggested that the patients were satisfied with their intraoperative care Problems occurred mainly in cognitive and experiential perspectives, such as the need for continuous access to information and coping with the anxiety related to the impending surgery It also emerged that special attention must be paid to keeping the patient warm in the operating theatre and to looking after emergency patients, younger patients, and patients who only remain in the operating department for a short period of tune The patients' evaluations of the standards of care tended to be less critical in hospital than they were a few weeks after discharge
Maternal thinking in dementia care
Authors: Haggstóm Terttu , Norberg Astrid
Published: November 2003

Carers of demented people living in a group dwelling were interviewed and observed individually and together The aim of the study was to illuminate the thinking of pre‐identified good dementia carers and to make explicit their means of understanding demented people The tape‐recorded and transcribed interviews were interpreted using a phenomenological hermeneutic method The findings showed that these carers explicitly referred to the concept of mother, used when explaining their ability to understand demented people They created a home‐like atmosphere together with the inhabitants The findings were interpreted metaphorically as maternal love, thinking and practice in creating an understanding relationship with the demented people they cared for This metaphorical aptitude considered the fulfilment of life for these demented people and included partly unconscious tools that the carers used to compensate for the loss of abilities suffered by the demented people The carers' attitudes towards the inhabitants of the ward and each other were based on respect as in a functioning family Their ambition was interpreted as an attempt to create an atmosphere that functioned not only as an institution, but as an incubator for human lives, which had become dependent on others for their survival and the preservation of their human dignity throughout their physical existence
Muscarinic modulation of endogenous noradrenaline release from adrenergic terminals in the guinea‐pig colon
Authors: Marino F. , Cosentino M. , De Ponti F. , Giaroni C. , Somaini L. , Bombelli R. , Ferrari M. , Aasen A.J. , Lecchini S. , Frigo G.
Published: November 2003

1 The present study examined the role of muscarinic receptors in the modulation of noradrenaline (NA) release in the guinea‐pig isolated distal colon. The spontaneous endogenous NA overflow assayed by HPLC‐ED was taken as an index of NA release from enteric noradrenergic nerve terminals.

2 Physostigmine (10 μm) significantly enhanced spontaneous endogenous NA overflow. Hyoscine (muscarinic antagonist), (R)‐(‐)‐trihexyphenidyl and telenzepine (M1‐selective antagonists), and 11[[2‐[(diethylamino)methyl]‐1‐piperydil]acetyl]‐5,11‐dihydro‐6H‐pyrido[2,3‐b][1,4]benzodiazepine‐6‐one (AF‐DX 116, M2‐selective antagonist) inhibited NA overflow in a concentration dependent manner, with the following EC50 values: 131.74 (18.19–953.96), 101.62 (58.83–175.60), 150 (60–330), 30 (5–170) nm, respectively. 4‐diphenylacetoxy‐N‐methylpiperidine methiodide (4‐DAMP, M1‐ and M3‐ selective antagonist) had no significant effect up to 100 μm.

3 The muscarinic agonist oxotremorine inhibited NA overflow in a concentration dependent manner, with an EC50 value of 0.67 (0.30–1.51) μm. The response to oxotremorine was inhibited by muscarinic antagonists with the following order of potency: hyoscine = (R)‐(‐)‐trihexyphenidyl = telenzepine > 4‐DAMP >> AF‐DX 116.

4 In the presence of 3 μm tetrodotoxin (TTX), the effect of oxotremorine and 4‐DAMP was unchanged, while hyoscine, (R)‐(‐)‐trihexyphenidyl, telenzepine and AF‐DX 116, instead of inhibiting, significantly enhanced NA overflow.

5 The present results indicate that, in the guinea‐pig colon, endogenous acetylcholine sustains spontaneous NA release by activating muscarinic receptors possibly located on interneurones. In addition, inhibitory muscarinic receptors may exist on adrenergic terminals.
Cardiac vagal effects of rilmenidine in the dog: comparison with clonidine
Authors: Boucher M. , Dubar M. , Chapuy E. , Chassaing C.
Published: November 2003

1 The cardiac vagal effects of rilmenidine (5 μg kg−1 min−1) and clonidine (0.5 μg kg−1 min−1) were studied in chloralose anaesthetized dogs.2 Rilmenidine and clonidine progressively reduced the vagal stimulation‐induced bradycardia. As indicated by the ED70, rilmenidine was about 23 times less potent than clonidine in this respect. Concomitantly, both drugs dose‐relatedly decreased heart rate and mean blood pressure with potency ratios of rilmenidine to clonidine of about 1:23 and 1:12, respectively.3 Importantly, the heart rate values observed under vagal stimulation during drug infusion never exceeded the values under basal vagal stimulation, and with both drugs large interindividual variations occurred under vagal stimulation.4 These results show that the vagal bradycardia inhibition produced by rilmenidine and clonidine results from their true bradycardic effects and not from actual cardiac vagolytic properties.
Different effect of anticholinergic agents and potassium channel openers on urinary bladder response to pelvic nerve stimulation in anaesthetized dogs
Authors: Sudoh K. , Masuda N. , Uchida W.
Published: November 2003

1 Effects of the anticholinergic agents atropine, oxybutynin and terodiline, and the potassium channel openers YM934 (2‐(3,4‐dihydro‐2,2‐dimethyl‐6‐nitro‐2H‐1,4‐benzoxazin‐4‐yl) pyridine N‐oxide) and cromakalim were examined on urinary bladder response to pelvic nerve stimulation in pentobarbital‐anaesthetized dogs.2 Pelvic nerve stimulation (PNS) produced a frequency‐dependent increase in intravesical pressure in anaesthetized dogs. The response to PNS was abolished by topical tetrodotoxin, and markedly inhibited by intravenous hexamethonium, suggesting a neurogenic origin for the in vivo contractile response.3 Atropine (0.3–3 mg kg−1 i.v.) and the anti‐neurogenic bladder agents, oxybutynin (1–10 mg kg−1 i.v.) and terodiline (1–10 mg kg−1 i.v.) dose‐dependently decreased the amplitude of the peak intravesical pressure response to PNS. At either frequency of PNS, these agents inhibited the response to a similar degree.4 The potassium channel openers YM934 (1–10 μg kg−1 i.v.) and cromakalim (3–30 μg kg−1 i.v.) dose‐dependently decreased the amplitude of the peak intravesical pressure response to PNS. The inhibitory effects of these drugs were more potent at lower than at higher frequencies of PNS.5 These data suggest that the inhibitory effects of potassium channel openers on urinary bladder response to PNS are different from those of anticholinergic agents. The preferential inhibitory effect of potassium channel openers on detrusor smooth muscle contraction at lower frequencies of PNS may represent new potential for the treatment of neurogenic bladder.
Adrenergic and nitrergic responses of the rat isolated anococcygeus muscle to a new toxin (makatoxin I) from the venom of the scorpion Buthus martensi Karsch
Authors: Gong J.P. , Gwee M.C.E. , Gopalakrishnakone P. , Manjunatha Kini R. , Chung M.C.M.
Published: November 2003

1 Makatoxin I (MkTx I) is a new toxin purified from the venom of the scorpion Buthus martensi Karsch. Contractile (excitatory, adrenergic) and relaxant (inhibitory, nitrergic) responses of the rat isolated anococcygeus muscle (Acm) to MkTx I were investigated.

2 MkTx I (0.28 μm) produced a rapid and very marked rise in the tone of the Acm which then gradually waned to the control baseline. Phentolamine (5 μm), guanethidine (5 μm), tetrodotoxin (2 μm) and reserpine pretreatment in vivo (5 mg kg−1 s.c. at 24 h and 5 mg kg−1 i.p. at 3 h) completely blocked the contractile responses of the Acm to MkTx I. The responses to noradrenaline (NA) were blocked by phentolamine, but were potentiated by guanethidine.

3 MkTx I (0.28 μm) also marked and rapidly relaxed the tone of the carbachol (CCh; 3 μm), precontracted Acm. The addition of sodium nitroprusside (SNP; 1 μm) also produced a marked and rapid relaxation of the Acm. TTx (2 μm) or NG‐nitro‐L‐arginine methylester (L‐NAME, 50 μm) markedly inhibited the relaxant responses of the Acm to field stimulation (FS) as well as to MkTx I, but not the responses to SNP.

4 Therefore, the contractile responses of the rat anococcygeus muscle to MkTx I can be attributed to the release of transmitter NA acting on postjunctional α‐adrenoceptors, whereas the relaxant responses of the Acm to MkTx I involve the release of nitric oxide as the neurotransmitter which, presumably, results in the activation of the enzyme guanylate cyclase leading to relaxation of the muscle.
Age‐related changes in the reactivity of post‐synaptic adrenoceptors in the rat vas deferens: differences between the epididymal and prostatic portion
Authors: Markus R. P. , De Avellar M. C. W.
Published: November 2003

1 Age‐related changes in the reactivity of postsynaptic α‐adrenoceptors of isolated portions (epididymal and prostatic) and in whole vas deferens have been studied using 4, 12 and 20 month‐old rats.

2 The pD2 values for adrenaline‐induced contractions were reduced in the epididymal portion and whole vas deferens of middle‐aged and old animals, but not in the prostatic portion. No age related change to phenylephrine or clonidine sensitivity was observed.

3 pA2 values of prazosin and yohimbine were not changed by aging in any preparation. Phentolamine pA2 values were reduced in the epididymal portion and in the whole vas deferens when adrenaline, but not when phenylephrine concentration–response curves were displaced by the antagonist. The mean pA2 value of yohimbine (6.78) indicates that this antagonist blocks α1‐adrenoceptors in the rat vas deferens.

4 The data presented here suggest that age‐related decreases in the sensitivity to adrenaline and phentolamine (when measured by displacing adrenaline concentration–effect curves) in the whole vas deferens are probably due to a variation in the proportion of α1‐adrenoceptor subtypes in the epididymal portion of the rat vas deferens.
Intracerebroventricular choline reverses hypotension induced by acute chemical sympathectomy
Authors: Gürün M. S. , Savci V. , Ulus I. H.
Published: November 2003

1 The effect of centrally administered choline on blood pressure was investigated in rats made hypotensive by chemical sympathectomy. Chemical sympathectomy was produced by intravenous (i.v.) injection of 50 mg kg−1 of 6‐hydroxydopamine (6‐‐OHDA). Intracerebroventricular (i.c.v.) administration of choline (50–150 μg) 2 h after 6‐OHDA treatment increased blood pressure and reversed the hypotension in a dose‐dependent manner without affecting heart rate. The pressor response was associated with an increase in plasma vasopressin levels.

2 Pretreatment of rats with the nicotinic receptor antagonist, mecamylamine (50 μg, i.c.v.), but not the muscarinic receptor antagonist atropine (10 μg, i.c.v.), blocked both the pressor and vasopressin responses to choline (150 μg). Pretreatment of rats with hemicholinium‐3 (HC‐3), a high affinity choline uptake inhibitor, greatly attenuated the pressor response to i.c.v. choline (150 μg).

3 The vasopressin V1 receptor antagonist, (β‐mercapto‐β,β‐cyclopentamethylenepropionyl‐O‐Me‐Try,Arg)‐vasopressin (10 μg kg−1; i.v.), given 5 min after i.c.v. choline, decreased the blood pressure but failed to return it to the pre‐choline levels. Prazosine (0.5 mg kg−1; i.p.), an antagonist of α‐adrenoceptors, also decreased blood pressure. Administration of both antagonists together eliminated the pressor response to choline, and the blood pressure was reduced further to below the pre‐choline levels.

4 It is concluded that i.c.v. choline can increase blood pressure in rats made hypotensive by acute chemical sympathectomy through the activation of central nicotinic receptors by presynaptic mechanisms. An elevation in plasma levels of both vasopressin and catecholamines (possibly released from the adrenal medulla) is involved in the pressor response to choline.
β3‐Adrenoceptors mediate smooth muscle relaxation in the rat lower oesophageal sphincter
Authors: Oriowo M. A.
Published: November 2003

1 The role of β3‐adrenoceptors in isoprenaline‐induced relaxation of carbachol‐precontracted ring segments of the rat lower oesophageal sphincter (LOS) was examined.

2 Isoprenaline (10−8m– 10−5m) relaxed ring segments of the LOS in a concentration‐dependent manner. Propranolol (10−7m) had very little antagonist effect on isoprenaline‐induced relaxation.

3 Dobutamine (10−7m– 10−4m), salbutamol (10−7m – 10−4m) and BRL 37344 (10−8– 10−5m) also all relaxed carbachol‐contracted ring segments of the LOS in a concentration‐dependent manner. The relaxant responses to these agonists were similarly not antagonized by propranolol (10−7m).

4 Cyanopindolol (10−6m), produced a parallel rightward displacement of isoprenaline, dobutamine, salbutamol and BRL 37344 concentration–response curves with similar potencies. The pKB values range from 7.3 ± 0.1 to 7.7 ± 0.2.

5 The relaxant effect of isoprenaline in the rat LOS was not inhibited by NG‐nitro‐l‐arginine (l‐NOARG; 3 × 10−5m), glibenclamide (10−5m) or tetraethylammonium (1 mm).

6 It was concluded that β3‐adrenoceptors mediate isoprenaline‐induced relaxation in rat lower oesophageal sphincter and that activation of these receptors was not linked to either ATPase‐, Ca2+‐dependent K+ channels or to NO release.
DMPP‐evoked increases in postganglionic sympathetic nerve activity and blood pressure occurs by two mechanisms in the rat
Authors: Martin J. R.
Published: November 2003

1 Intravenous administration of the ganglionic nicotinic receptor agonist DMPP (1,1‐dimethyl‐4‐phenylpiperazinium iodide) into urethane‐anaesthetized rats evoked dose‐dependent increases in mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA).

2 The ganglionic nicotinic receptor antagonists pentolinium and hexamethonium either alone or combined did not inhibit the increase in RSNA and MAP evoked by 50 to 200 μg kg−1 doses of DMPP. The increase in renal sympathetic nerve activity evoked by DMPP occurred as a brief burst in firing.

3 The increase in MAP, but not RSNA, evoked by DMPP in the presence of pentolinium was inhibited by the selective α1‐adrenergic receptor antagonist prazosin.

4 The non‐selective α‐adrenoceptor and NPY receptor antagonist benextramine also inhibited the increase in MAP without inhibiting the increase in RSNA. Surprisingly, the combination of benextramine and pentolinium, or benextramine and hexamethonium, completely blocked the DMPP‐evoked increase in RSNA and thus the increase in MAP.

5 The uptake1 antagonist desipramine combined with pentolinium did not affect the DMPP‐evoked increases in MAP or RSNA when compared to the responses evoked in the presence of pentolinium alone.

6 Adding the selective M1 muscarinic receptor antagonist telenzepine to pentolinium and prazosin did not inhibit the increase in RSNA evoked by a 100 μg kg−1 dose of DMPP.

7 While the DMPP‐evoked increase in MAP in the presence of ganglionic nicotinic receptor antagonists is primarily dependent upon activation of α1‐adrenoceptors, the increase in RSNA occurs via activation of ganglionic nicotinic receptors and activation of a mechanism susceptible to blockade by benextramine.
Use of [3H]‐clozapine as a ligand of the dopamine D4 receptor subtype in peripheral tissues
Authors: Ricci A. , Bronzetti E. , Rossodivita I. , Amenta F.
Published: November 2003

1 Molecular biology studies have documented the presence of peripheral dopamine D4 receptors. This site has not been characterized yet with classical radioligand binding assay techniques because of the lack of selective radioligands.

2 The atypical neuroleptic clozapine labelled with tritium ([3H]‐clozapine) has been proposed and sold as a radioligand for brain dopamine D4 receptors. However, the selectivity of [3H]‐clozapine for D4 receptor subtypes, and its specificity for brain dopamine receptors, have been questioned.

3 In this study dopamine D4 receptors were assayed in peripheral organs known to express them, such as rat atria and kidney, by using a radioligand binding assay technique with [3H]‐clozapine as the radioligand. Parallel experiments were performed using Chinese hamster ovary (CHO) cells transfected with the D4 receptor clone (variant D4.2).

4 [3H]‐Clozapine was bound to sections of rat atria and kidney. After appropriate blockade of sites other than dopamine receptors to which it can bind (i.e. muscarinic cholinergic, serotonergic and α‐adrenergic receptors), the radioligand was bound to a site displaying a pharmacological profile similar to that expressed by CHO cells transfected with the D4 receptor.

5 The above findings indicate that with appropriate protocols, [3H]‐clozapine may represent a radioligand for peripheral dopamine D4 receptors.
Autonomic components of the cardiovascular responses to an acoustic startle stimulus in rats
Authors: Baudrie V. , Tulen J. H. M. , Blanc J. , Elghozi J.‐L.
Published: November 2003

1 A loud acoustic stimulus was administered to rats prior to and after treatment with autonomic blockers in order to unravel the autonomic mechanisms of the blood pressure (BP) and heart rate (HR) responses to startle.

2 Six rats, implanted with a BP telemetric system, were used in a randomized crossover saline‐controlled (saline vs. autonomic blocker) study with a washout period of 7 days between each active session. A first acoustic stimulus (110 dB, 0.7 s) was administered. An autonomic blocker i.e. atropine methylnitrate (15 mg. kg−1), atenolol (15 mg. kg−1) or prazosin HCl (1 mg. kg−1), or physiological saline was administered i.p. 40 min prior to a second identical acoustic stimulus.

3 The average BP rise following the first stimulus was +25 mmHg and the average HR change was +17 bpm. The responses after autonomic blockades were affected as follows: atropine increased the HR rise (+45.1 ± 1.7 bpm), atenolol reversed the HR changes to a bradycardic response (−21.4 ± 9.1 bpm), after prazosin treatment the BP rise was reversed into a BP decrease (−11.3 ± 3.2 mmHg) and the HR increase was amplified (+76.0 ± 10.0 bpm). Finally, the delay for obtaining the maximal BP change was increased from 1.9 to 2.6 s following prazosin pretreatment.

4 These results indicate that the BP rise resulting from an acute loud noise depends on a vascular sympathetic activation (prevented with prazosin), which is partly blunted by vasodilation (revealed with prazosin). The evoked HR changes combine a sympathetic activation (fully expressed following atropine) and a vagal activation (unmasked with atenolol). Further experiments are necessary to document the vasodilatory component unmasked with prazosin.
Pressure modulates the reactivity of isolated rabbit epicardial arteries
Authors: García‐Roldán J.L. , Alonso M.J. , Marín J.
Published: November 2003

1 The magnitude of responses to prostaglandin F2α (PGF2α) and adenosine (ADO) in pressurized rabbit epicardial coronary arteries (367 ± 44 μm o.d.) with intact endothelium was assessed when they developed spontaneous tone.

2 The arteries were cannulated and changes in arterial diameter registered with an automated video perfusion system. The vessels, in the stabilization period at 60 mmHg, were divided into two groups, one exposed to a longitudinal stretch of +20% of unstretched initial length (Lo), and the other to +35% Lo, which developed spontaneous tone. In both cases, diameter–pressure curves were obtained by changing the intravascular pressure from 30 to 120 mmHg in aleatory steps of 30 mmHg (dp/dt = 15 mmHg s−1).

3 Diameter reduction of the arteries with stretch of +35% Lo in response to 1 μm PGF2α was greater than that with stretch of +20% Lo. Likewise, increase of the arteries that had +35% Lo in response to 1 μm ADO was greater than with +20% Lo.

4 Intravascular flow (40 μl min−1) increased the tone level of arteries. The addition of PGF2α enhanced this tone which was similar to that obtained with a stretch of +35% Lo and no flow, whereas the effect of ADO was increased.

5 These data indicate that the vasomotor responses of PGF2α and ADO are modulated by the degree of longitudinal stretch in epicardial arteries.
Quantitative studies of modern wet‐ground molluscan faunas from Bossington, Hampshire
Authors: Davies P. , Gale C.H. , Lees M.
Published: November 2003

There have been few quantitative studies of modern Mollusca in Britain, especially from wet‐ground areas. This is particularly true of the English chalklands, which is surprising given the focus of sub‐fossil molluscan research in that area. Those studies that are available highlight the difficulty of separating molluscan faunas from structurally complex habitats such as fen and carr. Quantitative molluscan data from a variety of wet‐ground habitats situated within the chalklands of southern England were analysed using an indirect ordination technique, Principal Components Analysis. This demonstrated that the separation of faunas from structurally complex wet‐ground habitats is possible. The numerical separation does not rely on indicator species, but is a function of variation of the predominant species. It is suggested that further studies of this type might aid the interpretation of sub‐fossil Mollusca from wet‐ground contexts.
Biogeographical comparison of winter bird assemblages in urban environments in Finland
Authors: Jokimäki Jukka , Suhonen Jukka , Inki Kimmo , Jokinen Simo
Published: November 2003

We studied biogeographical variation of urban bird assemblages in Finland. Winter birds were censused by single‐visit study plot method from thirty‐one centres of villages or towns along 950 km latitudinal extent. A total twenty‐eight bird species was observed and the average density was 61.2 ind./10 ha. The number of dominant species in study areas varied between two and seven and their proportion of the whole assemblage was over 70%. Species richness, but not the density of birds, decreased northwards in pooled data. Higher species richness in south than in north was mainly due to the higher amount of delayed migratory birds (e.g. waterbirds, finches) and southerly distributed bird species. However, in heavily urbanized areas species richness did not decrease northwards. This observation disagreed with the hypothesis that species richness decreased northwards. Bird density, but not species richness, increased with urbanization. In particular, feral pigeon, hooded crow and house sparrow had highest densities in most urbanized areas. As only few bird species are adapted to live in urban areas, species composition and dominant bird species were almost the same in the south and in the north. These urban birds may effectively use energy rich food in feeding tables and overcome the problems of severe climate in the north. This may be the reason why bird species richness does not decrease northwards in urban areas.
Parrot conservation and ecotourism in the Windward Islands
Authors: Christian Colmore , Potts Thomas , Burnett G. , Lacher Jr Thomas
Published: November 2003

The genus Amazona is represented on three islands in the Windward Islands. Since Europeans first visited the region in the fifteenth century, at least three parrot species have become extinct in the Windward Islands, and today all the extant parrots of the region are endangered. Several factors have contributed to the current plight of the parrots. The authorities in each of the islands of the Windward Islands that have endemic parrots have come to the realization that sound environmental management measures can complement rather than hinder national socioeconomic goals and objectives. Consequently, regional governments have begun to explore and foster linkages between conservation and other sectors of the economy. This article examines current parrot conservation efforts in the Windward Islands and the linkages which are being fostered between tourism and other sectors of the economy. Policy and research implications of the region's current parrot conservation efforts and ecotourism programme are also considered.
An ontological dilemma: epistemology and methodology of historical biogeography
Authors: Andersson Lennart
Published: November 2003

The task of historical biogeography is to reveal and explain the history of biotas and their historical connections. Historical «relationship» between biotas is defined as the sharing of descendants of the same ancestor. Several generalized patterns of relationship, rather than a single universal one, should be expected for any set of biotas or areas. Such generalized patterns must be sought by comparison of individual patterns, based on individual monophyletic groups. Generalized patterns of biota relationships are formally statements about numerical universals, while a pattern derived from an individual group is a statement about a particular. Such statements are not subject to testing in the Popperian sense; they may be falsified as well as verified. As in other historical sciences, explanation in historical biogeography is genetic in form and probabilistic in nature. An explanation is falsified when an explanatory premise is, and corroborated when an explanatory premise is verified. Two major methodologies exist to derive «area cladograms» from substituted (taxon) cladograms, Component Analysis and Parsimony Analysis. It is argued that Parsimony Analysis is the theoretically more satisfactory of these because it treats all sources of «error» in the same way, making no process‐related assumptions about the sources of conflicts. The rooting of area dendrograms is problematic. The rooting by an «allzero» outarea is theoretically unsound and the dendrogram should be rooted a posteriori adjacent to the ancestral area(s), or not at all.
Effects of rain forest disturbance and fragmentation: comparative changes of the raptor community along natural and human‐made gradients in French Guiana
Authors: Jullien Mathilde , Thiollay Jean‐Marc
Published: November 2003

A density index of every diurnal raptor species (Falconiformes) was obtained on 101 400 ha sample plots distributed among eight natural habitats and five man‐made habitats arranged along gradients of increasing forest degradation and fragmentation. The most significant structural parameter affecting species distribution was the tall canopy forest cover. Species richness, diversity and density all decreased with this mature forest cover index. Individual species and overall community densities decreased along the deforestation gradient but the species richness was partly maintained by species turnover. Six groups of species were identified according to their natural habitat preferences. Their distribution along the deforestation gradient was correlated with their natural habitat selection pattern. Thus the community composition of each vegetation or landscape type was predictable. Fifty‐six percent of the regional assemblage of species had their optimal density in the primary forest. A third of them were interior forest species highly sensitive to forest disturbance and opening. The other two‐thirds were upper canopy, gap or edge species more tolerant to forest fragmentation. The last twenty‐one species were associated with various coastal habitats, from dense forest patches to mangrove and savanna. Again, one third of them were strictly restricted to their specialized habitats while the last two‐thirds colonized human‐altered habitats and progressively replaced primary forest species with increasing deforestation. The maintenance of large areas of every natural habitat was essential for the conservation of (1) the whole population of a third of the total raptor diversity and (2) optimal and presumably potential source populations of most other species surviving in human‐modified habitats.
Niche segregation of terrestrial alpine beetles (Coleoptera) in relation to environmental gradients and phenology
Authors: Ottesen Preben
Published: November 2003

At Finse, south Norway (60°36′N, 7°30′E), 247 pitfall traps were set in forty‐seven alpine habitats. More than 21,000 individuals were caught, including thirteen species of Carabidae, forty‐six Staphylinidae and twenty‐eight species from other families. The locations were selected to maximize variation in soil water contents between the habitats, but minimize variation in time of snowmelt and aspect. Soil water content of the sites was highly correlated with soil organic content, and showed little variation between dry and rainy periods. A reciprocal averaging (RA) ordination of the sites and coleoptera species gave results similar to a direct gradient analysis based on soil water content of the sample sites, clearly showing the importance of habitat humidity. Riverside and mire habitats had the most distinct species composition. Niche segregation among the species was studied based on guild, soil humidity preference, seasonal activity pattern and altitudinal range. Most species were well separated along one or more of these niche dimensions. No species from the wettest habitats were autumn active, otherwise all permutations of the described niche dimensions were used. Carabids and herbivores from various families were all spring active, while 38% of the staphylinids, mainly in the subfamily Omaliinae, were autumn active. In cases where species were not clearly separated, their behaviour, morphology, size, diet, etc. were considered.