bluuebunny/crossref_metadata_2025 huggingface dataset:
Global climate change and soil carbon stocks; predictions from two contrasting models for the turnover of organic carbon in soil
Authors: Jones Chris , McConnell Claire , Coleman Kevin , Cox Peter , Falloon Peter , Jenkinson David , Powlson David
Published: December 2004

Enhanced release of CO2 to the atmosphere from soil organic carbon as a result of increased temperatures may lead to a positive feedback between climate change and the carbon cycle, resulting in much higher CO2 levels and accelerated global warming. However, the magnitude of this effect is uncertain and critically dependent on how the decomposition of soil organic C (heterotrophic respiration) responds to changes in climate. Previous studies with the Hadley Centre's coupled climate–carbon cycle general circulation model (GCM) (HadCM3LC) used a simple, single‐pool soil carbon model to simulate the response. Here we present results from numerical simulations that use the more sophisticated ‘RothC’ multipool soil carbon model, driven with the same climate data.

The results show strong similarities in the behaviour of the two models, although RothC tends to simulate slightly smaller changes in global soil carbon stocks for the same forcing. RothC simulates global soil carbon stocks decreasing by 54 Gt C by 2100 in a climate change simulation compared with an 80 Gt C decrease in HadCM3LC. The multipool carbon dynamics of RothC cause it to exhibit a slower magnitude of transient response to both increased organic carbon inputs and changes in climate. We conclude that the projection of a positive feedback between climate and carbon cycle is robust, but the magnitude of the feedback is dependent on the structure of the soil carbon model.
Nitrogen concentration and δ15N signature of ombrotrophic Sphagnum mosses at different N deposition levels in Europe
Authors: Bragazza Luca , Limpens Juul , Gerdol Renato , Grosvernier Philippe , Hájek Michal , Hájek Tomáš , Hajkova Petra , Hansen Ina , Iacumin Paola , Kutnar Lado , Rydin Håkan , Tahvanainen Teemu
Published: December 2004

Alteration of the global nitrogen (N) cycle because of human‐enhanced N fixation is a major concern particularly for those ecosystems that are nutrient poor by nature. Because Sphagnum‐dominated mires are exclusively fed by wet and dry atmospheric deposition, they are assumed to be very sensitive to increased atmospheric N input. We assessed the consequences of increased atmospheric N deposition on total N concentration, N retention ability, and δ15N isotopic signature of Sphagnum plants collected in 16 ombrotrophic mires across 11 European countries. The mires spanned a gradient of atmospheric N deposition from about 0.1 up to about 2 g m−2 yr−1. Mean N concentration in Sphagnum capitula was about 6 mg g−1 in less polluted mires and about 13 mg g−1 in highly N‐polluted mires. The relative difference in N concentration between capitulum and stem decreased with increasing atmospheric N deposition, suggesting a possible metabolic mechanism that reduces excessive N accumulation in the capitulum. Sphagnum plants showed lower rates of N absorption under increasing atmospheric N deposition, indicating N saturation in Sphagnum tissues. The latter probably is related to a shift from N‐limited conditions to limitation by other nutrients. The capacity of the Sphagnum layer to filter atmospheric N deposition decreased exponentially along the depositional gradient resulting in enrichment of the mire pore water with inorganic N forms (i.e., NO3−+NH4+). Sphagnum plants had δ15N signatures ranging from about −8‰ to about −3‰. The isotopic signatures were rather related to the ratio of reduced to oxidized N forms in atmospheric deposition than to total amount of atmospheric N deposition, indicating that δ15N signature of Sphagnum plants can be used as an integrated measure of δ15N signature of atmospheric precipitation. Indeed, mires located in areas characterized by greater emissions of NH3 (i.e., mainly affected by agricultural activities) had Sphagnum plants with a lower δ15N signature compared with mires located in areas dominated by NOx emissions (i.e., mainly affected by industrial activities).
Examining the total arrival distribution of migratory birds
Authors: Sparks T. H. , Bairlein F. , Bojarinova J. G. , Hüppop O. , Lehikoinen E. A. , Rainio K. , Sokolov L. V. , Walker D.
Published: December 2004

This paper reports on the total distribution of spring migration timing of willow warbler, chiffchaff and pied flycatcher at locations in the UK, Germany, Russia and Finland. This is the first time that high‐quality data based on known‐effort monitoring has been examined on a continental scale. First arrival dates, commonly reported in the literature, were positively correlated with mean arrival dates although they would not make good predictors of the latter. At all locations, at least one aspect of the arrival distribution of each species had got significantly earlier in recent years. The trend towards earliness was associated with warmer local temperatures and more positive winter North Atlantic Oscillation index. In years that were early, the arrival distribution became more elongated and skewed. Researchers should now investigate the consequences of earlier arrival on current and future bird populations.
Somatosensory evoked potentials predict neurolysis outcome in meralgia paraesthetica
Authors: Siu Timothy L. T. , Chandran K. Nadana
Published: December 2004

Background:  The role of somatosensory evoked potentials (SEP) in predicting the outcome of nerve entrapment syndrome following surgical release has not been fully verified.

Methods:  All patients included in our study had preoperative SEP recordings and had undergone neurolysis for treatment of meralgia paraesthetica by our senior author (KNC) between 1996 and 2000. The outcome of surgery was assessed 6 weeks after the procedure; follow up was continued at 3 month intervals if symptoms persisted. Telephone interviews were conducted to assess long‐term results. Univariate and multivariate logistic regression analyses were used to establish the predictive value of side‐to‐side N1 and P1 latency differences in obtaining complete relief of symptoms following surgery.

Results:  Twenty‐four patients who had preoperative SEP recordings and had undergone neurolysis for meralgia paraesthetica were followed for 4.0 ± 1.5 (SD) years. A prolonged side‐to‐side N1 latency difference (ΔN1) was found to be significantly associated with complete relief of symptoms at about 6 weeks postoperatively, after adjustment for age, sex and duration of symptoms (OR, 1.75; CI, 1.03−2.96). Logistic regression identified a critical cut‐off value of 8 ms (OR, 27.2; CI, 1.4−547.0). This association disappeared with longer follow up.

Conclusion:  Somatosensory evoked potentials provide significant data for prediction of good surgical outcome for meralgia paraesthetica. Re‐evaluation of the diagnosis, adequate trial of conservative treatments and special attention to anomalous branches are recommended for patients with low preoperative ΔN1 values.
Pharmacological characterization of α2‐adrenoceptor‐mediated responses in pig nasal mucosa
Authors: Corboz M. R. , Varty L. M. , Rizzo C. A. , Mutter J. C. , Rivelli M. A. , Wan Y. , Umland S. , Qiu H. , Jakway J. , McCormick K. D. , Berlin M. , Hey J. A.
Published: December 2004

1 Pig nasal mucosal strips were incubated with α‐adrenoceptor antagonists followed by α2‐adrenoceptor agonist concentration–response curves.

2 Contractions elicited by the α2‐adrenoceptor agonists BHT‐920 (pD2 = 6.16 ± 0.07), UK 14,304 (pD2 = 6.89 ± 0.13) and PGE‐6201204 (pD2 = 7.12 ± 0.21) were blocked by the α2‐adrenoceptor antagonist yohimbine (0.1 μm). In contrast, the α1‐adrenoceptor antagonist prazosin (0.03 μm) had no effect on the BHT‐920‐, UK 14,304‐ and PGE‐6201204‐induced contractions, but blocked the contractile response to the α1‐adrenoceptor agonist phenylephrine (pD2 = 5.38 ± 0.04) and the mixed α1‐ and α2‐adrenoceptor agonist oxymetazoline (pD2 = 6.30 ± 0.22).

3 The α2‐adrenoceptor antagonist yohimbine (0.01–0.1 μm, pA2 = 8.04), α2B/C‐adrenoceptor antagonist ARC 239 (10 μm, pKb = 6.33 ± 0.21), α2A/C‐adrenoceptor antagonist WB 4101 (0.3 μm, pKb = 8.01 ± 0.24), α2A‐adrenoceptor antagonists BRL44408 (0.1 μm, pKb = 6.82 ± 0.34) and RX 821002 (0.1 μm, pKb = 8.31 ± 0.35), α2C‐adrenoceptor antagonists spiroxatrine (1 μm, pKb = 7.32 ± 0.32), rauwolscine (0.1 μm, pKb = 8.16 ± 0.14) and HV 723 (0.3 μm, pKb = 7.68 ± 0.14) inhibited BHT‐920‐induced contractions in pig nasal mucosa.

4 The present antagonist potencies showed correlations with binding affinity estimates (pKi) obtained for these antagonists at the human recombinant α2A‐ and α2C‐adrenoceptors (r = 0.78 and 0.83, respectively) and with binding affinity estimates (pKd) obtained in pig native α2A‐ and α2C‐monoreceptor assays (r = 0.85 and 0.78, respectively). No correlation was observed for the α2B‐subtype.

5 In conclusion, contractile responses to phenylephrine, BHT‐920, UK 14,304, PGE‐6201204 and oxymetazoline indicate that α1‐ and α2‐adrenoceptors are present and mediate vasoconstriction in pig nasal mucosa. Furthermore, correlation analysis comparing antagonist potency in pig nasal mucosa with affinities for human recombinant α2‐adrenoceptors and native pig α2‐adrenoceptors suggest that α2A‐ and α2C‐adrenoceptor subtypes constrict pig nasal mucosa vasculature.
Is photoinhibition of zooxanthellae photosynthesis the primary cause of thermal bleaching in corals?
Authors: Smith David J. , Suggett David J. , Baker Neil R.
Published: December 2004

The bleaching of corals in response to increases in temperature has resulted in significant coral reef degradation in many tropical marine ecosystems. This bleaching has frequently been attributed to photoinhibition of photosynthetic electron transport and the consequent photodamage to photosystem II (PSII) and the production of damaging reactive oxygen species (ROS) in the zooxanthellae (Symbiodinium spp.). However, these events may be because of perturbations of other processes occurring within the zooxanthellae or the host cells, and consequently constitute only secondary responses to temperature increase. The processes involved with the onset of photoinhibition of electron transport, photodamage to PSII and pigment bleaching in coral zooxanthellae are reviewed. Consideration is given to how increases in temperature might lead to perturbations of metabolic processes in the zooxanthellae and/or their host cells, which could trigger events leading to bleaching. It is concluded that production of ROS by the thylakoid photosynthetic apparatus in the zooxanthellae plays a major role in the onset of bleaching resulting from photoinhibition of photosynthesis, although it is not clear which particular ROS are involved. It is suggested that hydrogen peroxide generated in the zooxanthellae may have a signalling role in triggering the mechanisms that result in expulsion of zooxanthellae from corals.
Context‐Oriented Model Development in Psychotherapy Planning (‘COMEPP’): a useful adjunct to diagnosis and therapy of severe personality disorders
Authors: Fischer‐Kern M. , Leithner K. , Hilger E. , Löffler‐Stastka H. , Schuster P.
Published: December 2004

Objective:  Pathogenous interpersonal (e.g. interfamilial) relationships and reference styles can compromise treatment efforts in severely disturbed (i.e. psychotic or borderline) patients. The integration of family‐ and individual‐centred starting points may be useful in establishing interdisciplinary treatment concepts in these patients. Context‐Oriented Model Development in Psychotherapy Planning (COMEPP) represents a diagnostic and therapy planning process, integrating both systemic and psychoanalytic conceptualizations.

Method:  COMEPP is exemplified by the case of a young man with psychotic personality disorder who had previously been unresponsive to pharmacological and psychological treatment.

Results:  After psycho‐dynamical conflicts (i.e. primitive projective processes from the patient's mother to her son) had been elucidated during the COMEPP process, a sufficient treatment setting could be established.

Conclusion:  COMEPP provides a psychotherapeutical approach to treatment planning on case‐specific premises and may serve as an adjunct to concomitant pharmacological and psychological treatment strategies in so‐called ‘therapy refractory’ patients.
Anxiety and depression: a 40‐year perspective on relationships regarding prevalence, distribution, and comorbidity
Authors: Murphy J. M. , Horton N. J. , Laird N. M. , Monson R. R. , Sobol A. M. , Leighton A. H.
Published: December 2004

Objective:  Building on a report about the prevalence of depression over time, this paper examines historical trends regarding anxiety in terms of its prevalence, its distribution by age and gender, and its comorbidity with depression. Methods for conducting such time trend analysis are reviewed.

Method:  Representative samples of adults were selected and interviewed in 1952, 1970, and 1992. Logistic regressions were used for statistical analysis.

Results:  Although twice as common as depression, the prevalence of anxiety was equally stable. Anxiety was consistently and significantly more characteristic of women than men. A re‐distribution of rates in 1992 indicated that depression but not anxiety had significantly increased among younger women (P = 0.03). Throughout the study, approximately half of the cases of anxiety also suffered depression.

Conclusion:  The relationships between anxiety and depression remained similar over time with the exception that depression came to resemble anxiety as a disorder to which women were significantly more vulnerable than men. Social and historical factors should be investigated to assess their relevance to this change.
The Munich vulnerability study on affective disorders: premorbid psychometric profile of affected individuals
Authors: Ising M. , Lauer C. J. , Holsboer F. , Modell S.
Published: December 2004

Objective:  We conducted a longitudinal high‐risk study to identify psychometric vulnerability markers for affective disorders.

Method:  We examined 82 healthy subjects [high‐risk probands (HRPs)] with at least one first‐degree relative suffering from an affective disorder. The premorbid psychometric profile of 20 HRPs who developed a psychiatric disorder during follow‐up was compared with the profile of control subjects without personal and family history of psychiatric disorders matched for age and gender.

Results:  Somatization, complaints (vegetative lability), and perception of strain are increased in HRPs who developed a psychiatric disorder. These alterations were not influenced by the time interval until the onset of the disorder.

Conclusion:  The premorbid psychometric profile in subjects at high risk for affective disorders is characterized by somatization, complaints, and elevated perception of strain. Together with previous findings our results suggest that these alterations can be regarded as potential vulnerability markers for affective disorders.
Hallucinatory experiences and onset of psychotic disorder: evidence that the risk is mediated by delusion formation
Authors: Krabbendam L. , Myin‐Germeys I. , Hanssen M. , Bijl R. V. , De Graaf R. , Vollebergh W. , Bak M. , Van Os J.
Published: December 2004

Objective:  To examine the hypothesis that the risk for onset of psychotic disorder in individuals with self‐reported hallucinatory experiences (HE) would be higher in those who developed delusional ideation (DE) than in those who did not.

Method:  A population sample of 4673 individuals were interviewed with the Composite International Diagnostic Interview at baseline and 1 and 3 years later. At year 3, clinical re‐interview took place to identify onset of psychotic disorder.

Results:  Given the presence of HEs at baseline, the increase in risk of having the psychosis outcome at year 3 was much higher in those with DE at year 1 than in those without DE (risk difference between individuals with and without DE: 18.72%, 95% CI: 2.22–35.23, χ2 = 4.94, df = 1, P = 0.026).

Conclusion:  The results are in line with current psychological theories stating that clinical outcome of psychosis‐like experiences is related to the development of secondary beliefs and appraisals.
Serum lipids in schizophrenia and other functional psychoses: a general population northern Finland 1966 birth cohort survey
Authors: Saari K. , Jokelainen J. , Veijola J. , Koponen H. , Jones P.B. , Savolainen M. , Järvelin M.‐R. , Lauren L. , Isohanni M. , Lindeman S.
Published: December 2004

Objective:  To compare fasting serum lipid concentrations of subjects with schizophrenia with a comparison group.

Method:  The study sample consists of 5654 members of the northern Finland 1966 birth cohort who participated in the field study with blood samples after overnight fasting and clinical examination in 1997–98. Total cholesterol (TC), high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, triglycerides (TG) and glucose were analyzed. Analysis of variance were used for comparing differences in lipids means between diagnostic categories.

Results:  Mean fasting TC in subjects with schizophrenia was 20 mg/dl higher than in the comparison group. TC and TG levels in the group of other psychoses resembled the schizophrenia group.

Conclusion:  Blood lipid levels in subjects with schizophrenia and other functional psychoses were high. As these persons are at special risk for hyperlipidemia their lipid levels should be regularly monitored, and cholesterol lowering diet, as well as medication, should be considered.
Obesity, dyslipidaemias and smoking in an inpatient population treated with antipsychotic drugs
Authors: Paton C. , Esop R. , Young C. , Taylor D.
Published: December 2004

Objective: The prevalence of cardiovascular disease in people with schizophrenia is known to be above population norms. In addition, many antipsychotic drugs have been associated with weight gain and some with dyslipidaemia. Our aims were to determine the apparent and actual prevalence of the modifiable risk factors for cardiovascular disease: obesity, hyperlipidaemia and smoking, in hospitalized patients treated with antipsychotic drugs.

Method: (i) Survey of clinical notes. (ii) Direct measurement of fasting lipids, body mass index and waist : hip ratio.

Results: Lipids were rarely monitored and body weight often not recorded making the apparent prevalence of these cardiovascular risk factors low. Smoking status was recorded. When directly measured, the actual prevalence of obesity was above population norms and two‐thirds of patients had a dyslipidaemia.

Conclusion: Routine screening for these modifiable risk factors followed by active intervention where appropriate could significantly reduce morbidity and mortality in this patient group.
The dental health of people with schizophrenia
Authors: McCreadie R. G. , Stevens H. , Henderson J. , Hall D. , McCaul R. , Filik R. , Young G. , Sutch G. , Kanagaratnam G. , Perrington S. , McKendrick J. , Stephenson D. , Burns T.
Published: December 2004

Objective:  To examine the dental health of community dwelling people with schizophrenia and to compare results with those in the general population.

Method:  Dental health of 428 people with schizophrenia in six different areas of the UK was assessed by a self‐report questionnaire.

Results:  Compared with the general population, significantly more of the younger patients were edentate (3–39% vs. 1–20%) and fewer had more than 20 teeth (70% vs. 83%). None of four dental health targets had been achieved in the patient population. More patients had last visited the dentist because of trouble with their teeth; fewer had visited for a check‐up. Fewer patients cleaned their teeth daily; this group had more negative symptoms.

Conclusion:  The dental health of people with schizophrenia is poor. Community mental health teams should encourage them to attend their community dentist regularly.
Angiotensin II in the brain and the autonomic control of the kidney
Authors: Johns Edward J.
Published: December 2004

The kidney plays a central role in ensuring cardiovascular homeostasis, in that it functions to ensure that the variation in fluid intake is matched to that lost through normal everyday metabolism. The autonomic nervous system, via the renal sympathetic nerves, allows kidney function to be adjusted dynamically in response to changes in sensory information arising from the cardiovascular system, the soma, viscera and the higher cortical centres. At the level of the kidney, the sympathetic nerves innervate the vascular and tubular components, thereby regulating renal haemodynamics and fluid reabsorption. The processing of sensory information by the central nervous system involves nuclei associated with cardiovascular control and it is these nuclei which are influenced by angiotensin II generated locally in the brain. The angiotensin II appears to act in a neuromodulatory fashion or as a neurotransmitter. There is now sound evidence that the baroreflex control of sympathetic outflow to the kidney, at least, is under tonic inhibitory control by brain angiotensin II, which also facilitates the impact of the somatosensory system in mediating sympatho‐excitation. The significance of brain angiotensin II in mediating reflex activation of the sympathetic nerves from other sensory systems has not yet been defined and needs to be resolved. Interestingly, it may be that deficits in the production of brain angiotensin II at these nuclei could contribute in part to the genesis of hypertension.
Differential effects of behaviour on sympathetic outflow during sleep and exercise
Authors: Miki Kenju , Yoshimoto Misa
Published: December 2004

The responses of renal and lumbar sympathetic outflow to changes in behavioural states were reviewed in this paper. During rapid eye movement (REM) sleep, renal sympathetic nerve activity was decreased while lumbar sympathetic nerve activity increased. These diverse changes in sympathetic nerve activity observed during REM sleep help explain the responses in regional blood flow to REM sleep; that is renal blood flow increased while muscle blood flow decreased. By contrast, exercise increased both renal and muscle sympathetic nerve activity. The degree of physical activity was correlated with the magnitude of the increases in renal and muscle sympathetic nerve activity. There was a significant (P < 0.05) linear relationship between renal sympathetic nerve activity and systemic arterial pressure over the transition between non‐rapid eye movement (NREM) sleep, quiet awake, moving and grooming states in the rats. This suggests that sympathetic outflows seem to be modulated quantitatively to meet cardiovascular demand caused by changes in the level of physical activity. It is therefore concluded that sympathetic outflow seems to be regulated in a state‐specific manner during sleep and exercise.
A role for the paraventricular nucleus of the hypothalamus in the autonomic control of heart and kidney
Authors: Coote J. H.
Published: December 2004

It is now well accepted that the sympathetic nervous system responds to specific afferent stimuli in a unique non‐uniform fashion. The means by which the brain transforms the signals from a single type of receptor into an appropriate differential sympathetic output is discussed in this brief review. The detection of and response to venous filling are used for illustration. An expansion of blood volume has been shown in a number of species to increase heart rate reflexly via sympathetic nerves and this effect is primarily an action of volume receptors at the venous–atrial junctions of the heart. Stimulation of these volume receptors also leads to an inhibition of renal sympathetic nerve activity. Thus the reflex response to an increase in plasma volume consists of a distinctive unique pattern of sympathetic activity to maintain fluid balance. This reflex is dependent on neurones in the paraventricular nucleus (PVN). Neurones in the PVN show early gene activation on stimulation of atrial receptors, and a similar differential pattern of cardiac sympathetic excitation and renal inhibition can be evoked by activating PVN neurones. Cardiac atrial afferents selectively cause a PVN GABA neurone‐induced inhibition within the PVN of PVN spinally projecting vasopressin‐containing neurones that project to renal sympathetic neurones. A lesion of these spinally projecting neurones abolishes the reflex. With regard to the cardiac sympathetics, there is a population of PVN spinally projecting neurones that selectively increase heart rate by the release of oxytocin, a peptide pathway that has no action on renal sympathetic outflow. In heart failure the atrial reflex becomes blunted, and evidence is emerging that there is a downregulation of nitric oxide synthesis and reduced GABA activity in the PVN. How this might give rise to increased sympathetic activity associated with heart failure is briefly discussed.
Vagal control of the heart: central serotonergic (5‐HT) mechanisms
Authors: Jordan David
Published: December 2004

Cardiac vagal preganglionic neurones (CVPNs) are located within the dorsal vagal nucleus (DVN) and the nucleus ambiguus (nA). In mammals, CVPNs within the nA have small myelinated axons and mediate major chronotropic effects, those in the DVN have non‐myelinated axons and mediate smaller chronotropic, dromotropic and inotropic effects. Numerous studies demonstrate important influences of serotonin (5‐HT) at multiple sites controlling autonomic outflows including the nucleus tractus solitarius (NTS) where cardiorespiratory afferent fibres terminate, and the CVPNs and rostral ventrolateral medulla (RVLM), the location of sympathetic premotor neurones. We have demonstrated roles for some of the numerous 5‐HT receptor subtypes (5‐HT1, 5‐HT2, 5‐HT3, 5‐HT4 and 5‐HT7) in brainstem regions involved in cardiac control. Intracisternal application of selective ligands was used to study the effect of 5‐HT receptors on heart rate and its reflex control. Further electrophysiological studies were also carried out to delineate their location and the mechanisms of action of these ligands. Blocking 5‐HT1A receptors attenuated bradycardias evoked by stimulating baroreceptor and cardiopulmonary afferents but not arterial chemoreceptors, whereas antagonizing 5‐HT7 receptors markedly attenuated all these reflex bradycardias. Within the DVN, nA and NTS, activation of 5‐HT1A receptors could excite or inhibit neurones. In the NTS 5‐HT2 receptors also had variable effects; 5‐HT2B receptors excite and 5‐HT2C receptors inhibit. Antagonism of 5‐HT3 receptors attenuated upper airway and cardiopulmonary reflex bradycardias; this is compatible with data showing that 5‐HT3 receptors excite DVN and NTS neurones by a glutamate‐dependent mechanism. The origin of the glutamate (neuronal or glial) remains unresolved but glia are a possibility as barorecptor‐sensitive NTS neurones receive few direct 5‐HT‐containing synaptic contacts. Thus, 5‐HT plays a critical role in the control of vagal outflow to the heart; however, why so many different receptors are involved, and their relative functional roles, remains unresolved.
Sympatho‐renal interactions in the determination of arterial pressure: role in hypertension
Authors: Grisk Olaf
Published: December 2004

Renal mechanisms and the sympathetic nervous system contribute to the development of arterial hypertension. Renal transplantation experiments in spontaneously hypertensive rats (SHRs) were performed to investigate how the sympathetic nervous system and the kidneys interact during the development and maintenance of hypertension. Our findings indicate that the rise in arterial pressure that occurs after transplantation of a kidney from a SHR into normotensive recipients is not mediated by elevations in sympathetic activity. However, chronic reductions in sympathetic tone reduce the rise in arterial pressure which can be induced by SHR renal grafts in normotensive recipients. Untreated SHRs transplanted with a kidney from sympathectomized donors have lower arterial pressure and reduced sodium sensitivity of arterial pressure compared to SHRs transplanted with a kidney from hydralazine‐treated donors. It is concluded that chronic non‐adapting changes in sympathetic activity modulate the degree to which renal mechanisms can cause hypertension in SHRs. Severe reduction in sympathetic tone during early ontogeny causes long‐term changes in renal function that mitigate hypertension development in SHRs even when the extrarenal neuro‐hormonal environment is restored.
Dynamic analysis of patterns of renal sympathetic nerve activity: implications for renal function
Authors: DiBona Gerald F.
Published: December 2004

Methods of dynamic analysis are used to provide additional understanding of the renal sympathetic neural control of renal function. The concept of functionally specific subgroups of renal sympathetic nerve fibres conveying information encoded in the frequency domain is presented. Analog pulse modulation and pseudorandom binary sequence stimulation patterns are used for the determination of renal vascular frequency response. Transfer function analysis is used to determine the effects of non‐renal vasoconstrictor and vasoconstrictor intensities of renal sympathetic nerve activity on dynamic autoregulation of renal blood flow.
Radio and Plasma Wave Observations at Saturn from Cassini's Approach and First Orbit
Authors: Gurnett D. A. , Kurth W. S. , Hospodarsky G. B. , Persoon A. M. , Averkamp T. F. , Cecconi B. , Lecacheux A. , Zarka P. , Canu P. , Cornilleau-Wehrlin N. , Galopeau P. , Roux A. , Harvey C. , Louarn P. , Bostrom R. , Gustafsson G. , Wahlund J.-E. , Desch M. D. , Farrell W. M. , Kaiser M. L. , Goetz K. , Kellogg P. J. , Fischer G. , Ladreiter H.-P. , Rucker H. , Alleyne H. , Pedersen A.
Published: December 2004

We report data from the Cassini radio and plasma wave instrument during the approach and first orbit at Saturn. During the approach, radio emissions from Saturn showed that the radio rotation period is now 10 hours 45 minutes 45 Â± 36 seconds, about 6 minutes longer than measured by Voyager in 1980 to 1981. In addition, many intense impulsive radio signals were detected from Saturn lightning during the approach and first orbit. Some of these have been linked to storm systems observed by the Cassini imaging instrument. Within the magnetosphere, whistler-mode auroral hiss emissions were observed near the rings, suggesting that a strong electrodynamic interaction is occurring in or near the rings.
NEGATIVE REFRACTION AND SUBWAVELENGTH FOCUSING USING PHOTONIC CRYSTALS
Authors: OZBAY EKMEL , GUVEN KAAN , CUBUKCU ERTUGRUL , AYDIN KORAY , ALICI B. KAMIL
Published: December 2004

In this article, we present an experimental and numerical study of novel optical properties of two-dimensional dielectric photonic crystals (PCs) which exhibit negative refraction. We investigate two mechanisms which utilize the band structure of the PC to generate a negative effective index of refraction (neff<0) and demonstrate the negative refraction experimentally. To the isotropic extend of neff, different PC slab structures are employed to focus the radiation of a point source. It is shown experimentally that the PC can generate an image of the source with subwavelength resolution in the vicinity of the PC interface. Using a different PC, one can also obtain a far field focusing. In the latter case, we explicitly show the flat lens behavior of the structure. These examples indicate that PC-based lenses can surpass limitations of conventional lenses and lead to novel optics applications.
INTERACTION OF THE SUPERPOSITIONS OF SQUEEZED DISPLACED FOCK STATES WITH ATOMIC SYSTEMS
Authors: ABD AL-KADER GAMAL M.
Published: December 2004

The properties of the squeezed displaced Fock states (SDFS) superpositions are reviewed. The interaction of these states with a two-level atom in cavity with the presence of additional Kerr medium is studied. Exact general matrix elements of the time-dependent operators of a Jaynes–Cummings model (JCM), in the presence of a Kerr medium, with these states are derived. The atomic inversion and photon number distribution are discussed.
ON THE PROPERTIES OF THE CAYLEY GRAPH OF RICHARD THOMPSON'S GROUP F
Authors: GUBA V. S.
Published: December 2004

We study some properties of the Cayley graph of R. Thompson's group F in generators x0, x1. We show that the density of this graph, that is, the least upper bound of the average vertex degree of its finite subgraphs is at least 3. It is known that a 2-generated group is not amenable if and only if the density of the corresponding Cayley graph is strictly less than 4. It is well known this is also equivalent to the existence of a doubling function on the Cayley graph. This means there exists a mapping from the set of vertices into itself such that for some constant K>0, each vertex moves by a distance at most K and each vertex has at least two preimages. We show that the density of the Cayley graph of a 2-generated group does not exceed 3 if and only if the group satisfies the above condition with K=1. Besides, we give a very easy formula to find the length (norm) of a given element of F in generators x0, x1. This simplifies the algorithm by Fordham. The length formula may be useful for finding the general growth function of F in generators x0, x1 and the growth rate of this function. In this paper, we show that the growth rate of F has a lower bound of [Formula: see text].
REPRESENTATIONS OF FREE PRODUCTS BY INFINITE UNITRIANGULAR MATRICES OVER FINITE FIELDS
Authors: OLIJNYK ANDRIJ , SUSHCHANSKY VITALY
Published: December 2004

An unambiguous construction of an embedding of the free product of n cyclic groups of order p into the the group of finite state infinite unitriangular matrices over the finite field of size p is presented.
TAMENESS OF THE PSEUDOVARIETY LS1
Authors: COSTA J. C. , TEIXEIRA M. L.
Published: December 2004

The notion of κ-tameness of a pseudovariety was introduced by Almeida and Steinberg and is a strong property which implies decidability of pseudovarieties. In this paper we prove that the pseudovariety LSl, of local semilattices, is κ-tame.
PROFINITE TOPOLOGIES IN FREE PRODUCTS OF GROUPS
Authors: RIBES LUIS , ZALESSKII PAVEL
Published: December 2004

Let [Formula: see text] be a nonempty class of finite groups closed under taking subgroups, quotients and extensions. We consider groups G endowed with their pro-[Formula: see text] topology, and say that G is 2-subgroup separable if whenever H and K are finitely generated closed subgroups of G, then the subset HK is closed. We prove that if the groups G1 and G2 are 2-subgroup separable, then so is their free product G1*G2. This extends a result to T. Coulbois. The proof uses actions of groups on abstract and profinite trees.
ASYNCHRONOUS AUTOMATA NETWORKS CAN EMULATE ANY SYNCHRONOUS AUTOMATA NETWORK
Authors: NEHANIV CHRYSTOPHER L.
Published: December 2004

We show that any locally finite automata network [Formula: see text] with global synchronous updates can be emulated by another one [Formula: see text], whose structure derives from that of [Formula: see text] by a simple construction, but whose updates are made asynchronously at its various component automata (e.g. possibly randomly or sequentially, with or without possible simultaneous updates at different nodes). By "emulation", we refer to the existence of a spatial-temporal covering 'local time', allowing one to project the behavior of [Formula: see text] continuously onto that of [Formula: see text]. We also show the existence of a spatial-temporal section of the asynchronous automata network's behavior which completely determines the synchronous global state of [Formula: see text] at every time step.

We give the construction of the asynchronous automata network, establish its freedom from deadlocks, and construct local time functions and spatial-temporal sections relating any posssible behavior of [Formula: see text] to the single corresponding behavior of [Formula: see text] on a given input sequence starting from a given initial global state.

This establishes that the behavior of any locally finite synchronous automata network actually can be emulated without the restriction of synchronous update, freeing us from the need of a global clock signal. Local information is sufficient to guarantee that the synchronous behavior of [Formula: see text] is completely determined by any asynchronous behavior of [Formula: see text] starting from a corresponding global state and given the same input sequence as [Formula: see text]. Moreover, the relative passage of corresponding local time at any two nodes in [Formula: see text] is bounded in a simple way by approximately one-third of the distance between them.

As corollaries, any synchronous generalized cellular automaton or synchronous cellular automaton can be emulated by an asynchronous one of the same type.

Implementation aspects of these asynchronous automata are also discussed, and open problems and research directions are indicated.
QUANTUM COMPUTATIONAL LOGICS AND FOCK SPACE SEMANTICS
Authors: DALLA CHIARA MARIA LUISA , GIUNTINI ROBERTO , LEPORINI ROBERTO
Published: December 2004

The theory of logical gates in quantum computation has suggested new forms of quantum logic, called quantum computational logics. The basic semantic idea is the following: the meaning of a sentence α is identified with a quantum information quantity, represented by a density operator of a Hilbert space, whose dimension depends on the logical complexity of α. At the same time, the logical connectives of the language are interpreted as operations defined in terms of quantum logical gates. Standard quantum computational models can be described as special cases of Fock space models, where the meaning of any sentence is localized in a precise sector of a Fock space ℱ. From an intuitive point of view, the increasing number of particles described in the different sectors of ℱ can be interpreted as increasing information.
QUANTUM SEARCH ALGORITHM CAN BE IMPROVED
Authors: GROVER LOV K.
Published: December 2004

Quantum search is a quantum mechanical technique for searching N possibilities in only [Formula: see text] steps. This has been proved to be the best possible algorithm for the exhaustive search problem in the sense that the number of queries it requires cannot be reduced. However, as this paper shows, the number of non-query operations can be reduced by a third without a single increase in the number of queries.
EXPERIMENTAL PROPOSAL OF SWITCHED "DELAYED-CHOICE" FOR ENTANGLEMENT SWAPPING
Authors: JENNEWEIN THOMAS , BRUKNER ČASLAV , ASPELMEYER MARKUS , ZEILINGER ANTON
Published: December 2004

Entanglement swapping is a fascinating generalization of quantum teleportation, where the entanglement between pairs is interchanged leading to entanglement between particles that never interacted. Extending the idea of Peres, we propose an experimental setup where the choice which quantum systems are finally entangled is made at a time after they have been registered and do not even exist anymore. Our proposed setup can be used in Third-Man Quantum Cryptography where a third party can control whether Alice and Bob are able to communicate secretly, but he does know their secret key.
QUANTUM COMPLEXITY THEORY GOALS AND CHALLENGES
Authors: GRUSKA JOZEF
Published: December 2004

Quantum complexity theory is a powerful tool that provides deep insights into Quantum Information Processing (QIP) and aims to do that also for Quantum Mechanics (QM), in general. This paper is a short review of the main and new motivations, goals, tools, results and challenges of quantum complexity, oriented mainly for pedestrians.
TAKING IT ON TRUST: REASON AND OBSERVABILITY IN QUANTUM COMPUTING
Authors: LUPACCHINI ROSSELLA
Published: December 2004

If quantum computing is located somewhere between physics and theoretical computing, a basic question concerns which characteristic features are derived from the latter. From a logical point of view, the concept of computation provides a definition of the natural process of calculare. It rests on trust that a procedure of reason can be reproduced mechanically. Turing argues for the adequacy of the concept by introducing a requirement of "observability," which is expressed through finiteness and locality conditions. However, according to the uncertainty principle, no computational path can be observed. How does quantum computing contend with Turing's constraints? What observables are relevant to the computation? This is an attempt to sharpen such questions.
QUANTUM ENTROPIES AND ENTANGLEMENT
Authors: BATLE J. , CASAS M. , PLASTINO A. R. , PLASTINO A.
Published: December 2004

The nature of quantum entropies, and its use in Quantum Information Theory in the form of (i) total entropy, (ii) relative entropy and (iii) conditional entropy is revisited. In this ordering, we first show the correlations existing between the total q-entropy and entanglement, quantified in the form of entanglement of formation. Then, we revisit the use of the quantum relative entropy as a measure of entanglement, and we finally discuss some features of the quantum conditional q-entropies, which are used in turn as a separability criterion.
SEMICLASSICAL QUANTUM COMPUTATION SOLUTIONS TO THE COUNT TO INFINITY PROBLEM: A BRIEF DISCUSSION
Authors: GÖKDEN BURÇ
Published: December 2004

In this paper we briefly define distance vector routing algorithms, their advantages and possible drawbacks. On these possible drawbacks, currently widely used methods split horizon and poisoned reverse are defined and compared. The count to infinity problem is specified and classified to be a halting problem, and a proposition stating that entangled states used in quantum computation can be used to handle this problem is examined. Several solutions to this problem by using entangled states are proposed and a very brief introduction to entangled states is presented.
QUANTUM INFORMATION — WHAT PRICE REALISM?
Authors: HAGAR AMIT
Published: December 2004

Recent suggestions to supply quantum mechanics (QM) with realistic foundations by reformulating it in light of quantum information theory (QIT) are examined and are found wanting by pointing to a basic conceptual problem that QIT itself ignores, namely, the measurement problem. Since one cannot ignore the measurement problem and at the same time pretend to be a realist, as they stand, the suggestions to reformulate QM in light of QIT are nothing but instrumentalism in disguise.
PARTICLE STATISTICS IN QUANTUM INFORMATION PROCESSING
Authors: OMAR YASSER
Published: December 2004

Particle statistics is a fundamental part of quantum physics, and yet its role and use in the context of quantum information have been poorly explored so far. After briefly introducing particle statistics and the Symmetrization Postulate, we argue that this fundamental aspect of nature can be seen as a resource for quantum information processing and present examples showing how it is possible to do useful and efficient quantum information processing using only the effects of particle statistics.
A PROPOSAL FOR AN OPTICAL IMPLEMENTATION OF A UNIVERSAL QUANTUM PHASE GATE
Authors: REBIĆ S. , VITALI D. , OTTAVIANI C. , TOMBESI P. , ARTONI M. , CATALIOTTI F. , CORBALÁN R.
Published: December 2004

Large optical nonlinearities occurring in a coherently prepared atomic system are shown to produce phase shifts of order π. Such an effect may be observed in ultracold rubidium atoms where it could be feasibly exploited toward the realization of a polarization phase gate.
USING EXPERIENCE FOR ASSESSING GRASP RELIABILITY
Authors: MORALES ANTONIO , CHINELLATO ERIS , FAGG ANDREW H. , DEL POBIL ANGEL P.
Published: December 2004

Autonomous manipulation is a key issue for a humanoid robot. Here, we are interested in a vision-based grasping behavior so that the robot can deal with previously unknown objects in real time and in an intelligent manner. Starting from a number of feasible candidate grasps, we focus on the problem of predicting their reliability using the knowledge acquired in previous grasping experiences. A set of visual features which take into account physical properties that can affect the stability and reliability of a grasp are defined. A humanoid robot obtains its grasping experience by repeating a large number of grasping actions on different objects. An experimental protocol is established in order to classify grasps according to their reliability. A prediction/classification strategy is defined which allows the robot to predict the outcome of a grasp only analyzing its visual features. The results indicate that the defined features do characterize grasp quality and that the classification method is adequate to predict the reliability of a grasp.
CONTROLLING A MOTORIZED MARIONETTE WITH HUMAN MOTION CAPTURE DATA
Authors: YAMANE KATSU , HODGINS JESSICA K. , BROWN H. BENJAMIN
Published: December 2004

In this paper, we present a method for controlling a motorized, string-driven marionette using motion capture data from human actors and from a traditional marionette operated by a professional puppeteer. We are interested in using motion capture data of a human actor to control the motorized marionette as a way of easily creating new performances. We use data from the hand-operated marionette both as a way of assessing the performance of the motorized marionette and to explore whether this technology could be used to preserve marionette performances. The human motion data must be extensively adapted for the marionette because its kinematic and dynamic properties differ from those of the human actor in degrees of freedom, limb length, workspace, mass distribution, sensors, and actuators. The motion from the hand-operated marionette requires less adaptation because the controls and dynamics are a closer match. Both data sets are adapted using an inverse kinematics algorithm that takes into account marker positions, joint motion ranges, string constraints, and potential energy. We also apply a feedforward controller to prevent extraneous swings of the hands. Experimental results show that our approach enables the marionette to perform motions that are qualitatively similar to the original human motion capture data.
RECOGNITION OF ACTIONS IN DAILY LIFE AND ITS PERFORMANCE ADJUSTMENT BASED ON SUPPORT VECTOR LEARNING
Authors: MORI TAKETOSHI , SHIMOSAKA MASAMICHI , HARADA TATSUYA , SATO TOMOMASA
Published: December 2004

This paper presents a recognition method for human actions in daily life. The system deals with actions related to regular human activity such as walking or lying down. The main features of the proposed method are: (i) simultaneous recognition, (ii) expressing lack of clarity in human recognition, (iii) defining similarities between two motions by utilizing kernel functions derived from expressions of actions based on human knowledge, (iv) robust learning capability based on support vector machine. Comparison with neural networks optimized by a back propagation algorithm and decision trees generated by C4.5 proves that the accuracy of recognition in the proposed method is superior to others. Recognizing actions in daily life robustly is expected to ensure smooth communication between humans and robots and to enhance support functionality in intelligent systems.
SELF-SIMILAR SOLUTIONS OF TWO-DIMENSIONAL CONSERVATION LAWS
Authors: KEYFITZ BARBARA LEE
Published: December 2004

Self-similar reduction of an important class of two-dimensional conservation laws leads to boundary value problems for equations which change type. We have established a method for solving free boundary problems for quasilinear degenerate elliptic equations which arise when shocks interact with the subsonic (nonhyperbolic) part of the solution. This paper summarizes the principal features of the method.

A preliminary version of these notes formed the basis of a series of three lectures at the Newton Institute in April, 2003. They are a report of research carried out jointly with Sunčica Čanić, Eun Heui Kim and Gray Lieberman.