bluuebunny/crossref_metadata_2025 huggingface dataset:
Atherosclerotic Occlusive Extracranial Vertebral Artery Disease:
Authors: WEHMAN J. CHRISTOPHER , HANEL RICARDO A. , GUIDOT CHARLES A. , GUTERMAN LEE R. , HOPKINS L. NELSON
Published: August 2004

Background: Atherosclerotic occlusive disease of the vertebral artery (VA) affects a significant proportion of patients with cerebrovascular disease and can cause significant morbidity and mortality despite maximal medical therapy. Careful selection of both symptomatic and asymptomatic patients for intervention based on neurological symptoms, as well as anatomical and hemodynamic considerations, is essential.

Methods: To achieve proper results with angioplasty and stenting, standard endovascular techniques are modified for the unique anatomical considerations of the VA. Several technical nuances are described here to aid in the endoluminal revascularization of the VA.

Results: Technical success (<50% residual diameter stenosis) rates ranging from 94 to 98% and low rates of periprocedural complications have been achieved with VA angioplasty and stenting in select series with angiographic follow‐up. The long‐term success in those series is limited by the high (10–43%) rate of recurrent stenosis. Proper placement of the stent can reduce the risk of periprocedural complications and restenosis. In‐stent stenosis appears most commonly during the first 6–12 months after stent placement, but does not appear to correlate with return of neurological symptoms. We believe the high rate of recurrent stenosis makes follow‐up angiography essential, especially in the first 12 months after the procedure.

Conclusion: Endovascular VA angioplasty with stent placement provides an innovative approach to treat a difficult clinical entity. Evolving therapies, including drug‐eluting stents or bioresorbable stents, may prove to provide better long‐term results.
The Coalitionary Process in Initiating Family Therapy
Authors: SLUZKI CARLOS E.
Published: August 2004

The observation and use of the coalitionary process constitute a substantial component of family therapy. Through monitoring this variable, the therapist can rationally establish basic ground rules, that is, lay down metacommunicational principles, that will frame and guide an effective course of treatment. In addition, as the coalitionary configuration in the course of family therapy replicates crucial family stereotypes, its careful analysis allows the calibration and refinement of therapeutic strategies.
Brief Therapy: Two's Company
Authors: de SHAZER STEVE
Published: August 2004

The triad is a key element in family therapy. It is clinically useful to conceptualize it as a unit with a structure of its own. This paper suggests that a typical triadic system consists of a pair of allies and an isolate, or “odd‐man‐out,” all of whom are “stuck” in a rigid pattern that has become dysfunctional. The therapist can break the pattern by developing interventions specifically designed to create new alliances and thus broaden the family's behavioral repertoire.
Family Puppet Interview
Authors: IRWIN ELEANOR C. , MALLOY ELAINE S.
Published: August 2004

At the Pittsburgh Child Guidance Center and the Family Therapy Clinic of Western Psychiatric Institute and Clinic, a number of expressive modalities have been utilized in work with individuals, groups and families. One technique that has been clinically rewarding in diagnosis as well as in therapy has been the Family Puppet Interview, a symbolic and interactive procedure that involves the whole family simultaneously. The value of this activity lies not only in the wealth of interactive data but in the symbolic family fantasy material that the interview generates. This paper will describe the procedure and present several case examples to illustrate its application.
“Normal” Sex Roles: An Historical Analysis
Authors: PEAL ETHEL
Published: August 2004

Parental sex‐role performance has been used as a criterion for differentiating normal and pathogenic families. Sex roles assumed to be normative are normative only for a specific society at a specific time. Sex roles assumed to be normative in the modern, urban, middle‐class family were determined by economic and social changes that took place in the early nineteenth century. These changes effected a new division of function between the sexes that had serious psychological consequences. A behavior code was formulated as a social response to the need to facilitate adaptation. The behavior prescribed in this code is behavior now defined by sociologists as normative. The problems the code attempted to alleviate have not diminished, and there is evidence suggesting that the prescribed behavior is itself a source of psychological strains. Social role performance, therefore, is an unsatisfactory criterion for identifying pathogenic families.
The Families of Drug Abusers: A Literature Review
Authors: HARBIN HENRY T. , MAZIAR HOWARD M.
Published: August 2004

This paper reveiws all relevant literature concerning the family background of compulsive drug abusers. The main content of the completed research is summarized and methodological criticisms are made. Future considerations for research on families of drug abusers are suggested.
Depression Following Stroke: Brief, Problem‐Focused Family Treatment
Authors: Watzlawick Paul , Coyne James C.
Published: August 2004

The brief, problem‐focused treatment of a case of depression is described. Members of a family were seen in the treatment of a 58‐year‐old man suffering from depression secondary to two strokes. The identified patient did not attend any of the five sessions. Therapeutic interventions emphasized interdicting the self‐defeating efforts of family members to be supportive and encouraging. It is proposed that successful therapeutic interventions often involve changing the behavior of persons other than the identified patient but that traditional therapists have avoided the full implication of this. Ethical concerns about this mode of treatment are considered.
Joint Custody: An Exploration of the Issues
Authors: NEHLS NADINE , MORGENBESSER MEL
Published: August 2004

Joint custody, an increasingly popular custody decision, allows both divorced parents to share equally the rights and responsibilities of child‐rearing following their divorce. The authors discuss the potential positive and negative effects of this new and highly controversial custody decision by reviewing relevant research and theoretical concepts. Suggestions for further research are offered.
The Significance of Cultural Patterning for the “Alcoholic Family”
Authors: ABLON JOAN
Published: August 2004

This paper presents findings from a recent study of a population of middle‐class Catholic families, primarily Irish, German, and Italian, among whom alcohol‐related problems are frequent and severe. To understand alcohol usage in this population, a knowledge of the historical and cultural roles of drinking in the relevant ethnic or national groups and a holistic view of contemporary family life are essential. It is suggested that massive social controls in major areas of family life are closely related to problematic drinking behavior. The delineation of cultural prescriptions regarding behaviors and attitudes directly and indirectly related to drinking patterns may contribute a significant cultural dimension to proposed models of the “alcoholic family” system.
Using Video Playback to Train Family Therapists
Authors: KRAMER JEANNETTE R. , REITZ MIRIAM
Published: August 2004

This paper presents a small group design, part of a two‐year training program in family therapy, using video playback to enhance self‐awareness. Congruence among multiple channels of communication enhances therapist effectiveness; the visual mode has unique advantages in identifying incongruence. Details of the design are described, emphasizing the staging of gradually increased risks from general exercises to more specifically personal foci. The concurrent building of an atmosphere of safety is essential for risk‐taking.
Short‐Term Family Therapy and Pathological Grief Resolution with Children and Adolescents
Authors: ROSENTHAL PERIHAN ARAL
Published: August 2004

This paper describes the use of short‐term family therapy as a new modality for resolution of pathological grief with young children and adolescents. These families' experience with other modalities of therapy had been disappointing. The unusual cohesiveness of the family was evidenced by resistance to actual or threatened separation. Such activities as entering individual therapy or going to school, camp, boarding school, or residential treatment were hard to accomplish because of the difficulty with earlier grieving processes and the associated failure of decathexis of the lost person.
Some Cotherapy Techniques With Families
Authors: HANNUM JAMES W.
Published: August 2004

The use of cotherapists in family therapy is explored with particular attention to the unique ways in which this form of therapy can aid the therapeutic process. A basic cotherapy transactional pattern is described, and a number of techniques specifically for use in cotherapy with families and couples are discussed.
A Critique of the Wells and Dezen Review of the Results of Nonbehavioral Family Therapy
Authors: STANTON M. DUNCAN , TODD THOMAS C.
Published: August 2004

Although the Wells and Dezen review made many valuable points about family therapy outcome research, their handling of the various included studies appeared uneven. To test this impression, a content analysis was performed on the “favorableness” or “positiveness” of the statements made by Wells and Dezen about the studies they reviewed. The degree of positiveness was compared across studies with the Design Quality and with the level of sophistication of these studies. All of the statistical correlations were negative — half of them significantly so — a result completely opposite to what would be expected. We conclude that Wells and Dezen tended to give undue praise to many uncontrolled studies and inordinate criticism to more sophisticated and better‐designed research. In addition, other inconsistencies in the evaluation of studies were noted. Further, specific studies were presented in a distorted and inaccurate manner, and without proper attention to statistical principles. In sum, it appears that Wells and Dezen (a) have not been sufficiently careful in their analysis of the reviewed research, and (b) have, through their evaluative remarks, provided a biased review which obscures many important comparisons within this field.
How One Family Perceives Another: The Relationship Between Social Constructions and Problem‐Solving Competence
Authors: REISS DAVID , COSTELL RONALD , BERKMAN HELEN , JONES CAROLE
Published: August 2004

This paper delineates a rarely studied but important family process: how a family perceives and understands the relationships in other families it knows. We hypothesize that these perceptions of other families are fundamental components of a family's shared construing of its social world. Families differ in how they perceive other families, specifically, and in their approach to construing or apprehending their social world, generally. We have hypothesized that these general differences also play a crucial role in shaping the style and competence of family problem‐solving. A family's approach to any problem depends upon how it construes or interprets the social context of that problem. Using these general concepts of family life, we construct specific hypotheses linking family problem‐solving and interfamily perception. We describe methods for measuring both family problem‐solving and how a family perceives other families. Findings confirm our major hypothesis: A family that searches for underlying and subtle patterns in a problem‐solving situation will develop a more differentiated and organized conception of other families.
The Case of Helen D.: A Woman Who Learned to Suffer
Authors: KEITH DAVID V.
Published: August 2004

Despite our earnest wish to be useful to patients, we sometimes fail. Part of the difficulty often has to do with the expectations that the patient brings to therapy. Another contribution to an impasse may be the psychiatrist's theoretical orientation. This review illustrates a playful distortion of the doctor‐patient relationship so as to develop an alliance with a difficult patient. The involvement of part of her family in the long‐term treatment facilitated her growth out of a biopsychosocial swamp.
The Problem of Fusion in the Lesbian Relationship
Authors: KRESTAN JO‐ANN , BEPKO CLAUDIA S.
Published: August 2004

This paper is an attempt to outline a set of hypotheses about the kinds of issues that intensify the problem of fusion in committed lesbian partnerships. We consider also why the likelihood is so great of fusion occurring as a response to stresses both internal and external to the relationship. We have chosen to address the problem from a systems perspective because we feel that the most productive clinical interventions for lesbian couples depend upon an awareness of the problems inherent in the couple's attempt to define the rules of their relationship within the context of a larger system in which no rules relating to them exist. We shall outline our basic conceptual approach to the problem, offer case examples of a “fused” lesbian couple, and discuss implications for treatment.
Researching the Family Theories of Schizophrenia: An Exercise in Epistemological Confusion
Authors: DELL PAUL F.
Published: August 2004

Some, but not all, of the family theories of schizophrenia entail a shift from the Aristotelian/Cartesian/Newtonian epistemology of individual psychology to a systemic epistemology of pattern. Perhaps the most significant (and underappreciated) aspect of this epistemological shift pertains to etiology: The family theories of schizophrenia espoused by Bateson et al. and by Wynne and Singer do not claim that parents or families cause schizophrenia. The persistent failure of researchers to appreciate this has led to many fruitless studies that have sought to discover a causal link between the thought disorder and communication deviance of parents and the schizophrenia of their offspring. This paper reviews from an epistemological viewpoint the empirical literature that has attempted to assess the validity of the family theories of schizophrenia. Particular attention is given to restating and extending the epistemology of pattern within which schizophrenia occurs. The conventional psychiatric approaches to schizophrenia are shown to play an active role within the schizophrenic pattern.
Lingering Terminal Illness and the Family: Insights From Literature
Authors: BERTMAN SANDRA L.
Published: August 2004

Literature invites us to enter into the human dilemma in a manner that is different from but no less penetrating than clinical observation. The writer's craft uncovers realities other than the statistically measurable and objective. In languages far from the strictly literal and closer to indirection, symbolism, and aesthetics, the literary artist probes imagination and consciousness. He presents us with transcripts of conversations replete with intonations, and we thereby become privy to motivations and inner thoughts. The artistry of a piece of fiction, autobiographical essay, poem, or drama propels us into empathetic relationships. We feel with the emotions of the involved dramatis personae; we witness their interactions; we experience their points of view. And by such participation, we, the readers, come to perceive and even refine our own.

Themes of chronic illness, dying, and bereavement are certainly not alien to literature. This paper explores several literary moments that may help the professional who is working with these issues to have a broader appreciation of the subtleties of these human experiences.
Symptom Bearer as Marital Distance Regulator: Clinical Implications
Authors: BYNG‐HALL JOHN
Published: August 2004

Certain families experience conflict in regulating their interpersonal distance because they are afraid of separation and intimacy. A couple that lives in the shadow of this double‐ended catastrophe may triangle in a “go‐between” to bring them together if they get too far apart, or separate them when they are too close. Ambivalence about the couple's relationship predisposes a family member, often an in‐law or child, to be recruited to this role. The “go‐between's” ambivalence then becomes the couple's homeostat, and symptoms are likely to appear in this individual. Implications for family therapy are illustrated by the through a full‐length case study.
The Use of Time Limits in Brief Psychotherapy: A Comparison of Six‐Session, Twelve‐Session, and Unlimited Treatment with Families
Authors: FISHER STUART G.
Published: August 2004

This study compared the relative effectiveness of two durations of time‐limited psychotherapy with time‐unlimited treatment and a waiting list control group. Thirty‐seven families applying for treatment at a child guidance clinic were randomly assigned to one of four treatment conditions: (a) time‐limited therapy of 6 sessions within 8 weeks; (b) time‐limited therapy of 12 sessions within 16 weeks; (c) time‐unlimited therapy; and (d) a waiting list control group in which families waited approximately four months before beginning treatment. Outcome was assessed from multiple sources: parents, child, therapist, family interaction ratings, and missed and canceled sessions. Analysis of data provided some evidence that families who received treatment fared better than those on the waiting list. There were no consistent differences between 6‐session, 12‐session, and unlimited therapy. A model is proposed for the further investigation of time‐limited treatment.
Convening Strategies in Family Therapy
Authors: TEISMANN MARK W.
Published: August 2004

Specific strategies for assembling or convening significant and often reluctant family members for family therapy seem undeveloped in the literature. The author develops and organizes specific convening methods and exemplifies these methods for clinical application. Methods adopted from strategic family therapists, including Haley, Selvini Palazzoli, and Watzlawick, are presented.
Distress in Clients and Significant Others: The Question of Causality
Authors: WRIGHT BARRY M. , STOFFELMAYR BERTRAM E.
Published: August 2004

Previous research documenting the association between the level of client disturbance and distress in a significant other has generated two competing causal models. Investigators measuring the level of family burden have suggested that it is the discharged patient who causes distress in the family. Investigators of family factors in patient relapse have suggested that it is the family who disturbs the patient. In this study the relative strengths of these two causal models are compared in a sample of outpatients over a six‐month period of time. The data indicate that the significant other is causally predominant in the exacerbation of client disturbance.
Expanding Uses of the Telephone in Family Therapy
Authors: COPPERSMITH EVAN IMBER
Published: August 2004

The telephone has been used as an instrument for live supervision. This article describes innovative uses of the telephone by a family therapy training team, including (a) strategic calls to the therapist; (b) calls from the team to family members; and (c) calls between family members. Case examples describing the interventions and their impact are given. Both training and therapeutic benefits are discussed.
Contraction augments L‐type Ca2+ currents in adherent guinea‐pig cardiomyocytes
Authors: Rueckschloss Uwe , Isenberg Gerrit
Published: August 2004

As integrins are thought to function as mechanoreceptors, we studied whether they could mediate mechanical modulation of the L‐type Ca2+ channel current (ICa) in guinea‐pig cardiac ventricular myocytes (CVMs). CVMs were voltage clamped with 280 ms pulses from −45 to 0 mV at 0.5 Hz (1.8 mm[Ca2+]o, 22°C). Five minutes after whole‐cell access (designated as 0 min) peak ICa was determined from a current–voltage (I–V) curve. Additional recordings were made after 5, 10 and 15 min. At control, ICa was not stable, but ran down during these periods. This run‐down of ICa was attenuated by soluble fibronectin (FN) and was changed to an enhancement of ICa when CVMs were attached to FN‐coated coverslips. Soluble peptide containing the integrin binding sequence of FN, Arg‐Gly‐Asp (RGD motif), did not modulate ICa; however, ICa increased in stimulated CVMs attached to RGD peptide‐coated coverslips. The effect was not specific to integrins, because attachment to poly‐d‐lysine‐coated coverslips also augmented ICa in stimulated CVMs. Augmentation of ICa by immobilized FN required rhythmical contraction of attached CVMs, because it was attenuated without electrical stimulation and after cell dialysis with the calcium chelator BAPTA. Furthermore, contraction‐induced augmentation of ICa in FN‐attached CVMs was sensitive to inhibition of protein kinase C (PKC; by Ro‐31–8220), inhibition of tyrosine kinase activity (herbimycin A) and cytoskeletal depolymerization (cytochalasin D or colchicine). We attribute augmentation of ICa to the activation of signalling cascades by shear forces that are generated when CVMs contract against attachment; in vivo similar signals may occur when CVMs contract against attachment of integrins to the extracellular matrix.
Regulation of hormone‐sensitive lipase activity and Ser563 and Ser565 phosphorylation in human skeletal muscle during exercise
Authors: Roepstorff Carsten , Vistisen Bodil , Donsmark Morten , Nielsen Jakob N. , Galbo Henrik , Green Kevin A. , Hardie D. Grahame , Wojtaszewski Jørgen F. P. , Richter Erik A. , Kiens Bente
Published: August 2004

Hormone‐sensitive lipase (HSL) catalyses the hydrolysis of myocellular triacylglycerol (MCTG), which is a potential energy source during exercise. Therefore, it is important to elucidate the regulation of HSL activity in human skeletal muscle during exercise. The main purpose of the present study was to investigate the role of 5′AMP‐activated protein kinase (AMPK) in the regulation of muscle HSL activity and Ser565 phosphorylation (the presumed AMPK target site) in healthy, moderately trained men during 60 min bicycling (65%). α2AMPK activity during exercise was manipulated by studying subjects with either low (LG) or high (HG) muscle glycogen content. HSL activity was distinguished from the activity of other neutral lipases by immunoinhibition of HSL using an anti‐HSL antibody. During exercise a 62% higher (P < 0.01)α2AMPK activity in LG than in HG was paralleled by a similar difference (61%, P < 0.01) in HSL Ser565 phosphorylation but without any difference between trials in HSL activity or MCTG hydrolysis. HSL activity was increased (117%, P < 0.05) at 30 min of exercise but not at 60 min of exercise. In both trials, HSL phosphorylation on Ser563 (a presumed PKA target site) was not increased by exercise despite a fourfold increase (P < 0.001) in plasma adrenaline. ERK1/2 phosphorylation was increased by exercise in both trials (P < 0.001) and was higher in LG than in HG both at rest and during exercise (P= 0.06). In conclusion, the present study suggests that AMPK phosphorylates HSL on Ser565 in human skeletal muscle during exercise with reduced muscle glycogen. Apparently, HSL Ser565 phosphorylation by AMPK during exercise had no effect on HSL activity. Alternatively, other factors including ERK may have counterbalanced any effect of AMPK on HSL activity.
Stage‐dependent dynamics and modulation of spontaneous waves in the developing rabbit retina
Authors: Syed Mohsin Md. , Lee Seunghoon , Zheng Jijian , Zhou Z. Jimmy
Published: August 2004

We report here a systematic investigation of the dynamics, regulation and distribution of spontaneous waves in the rabbit retina during the course of wave development prior to eye opening. Three major findings were obtained in this longitudinal study. (1) Spontaneous retinal waves underwent three developmental stages, each of which displayed distinct wave dynamics, pharmacology and mechanism of generation and regulation. Stage I waves emerged prior to synaptogenesis and appeared as frequent, fast propagating waves that did not form spatial boundaries between waves. These waves could be inhibited by blockers of gap junctions and adenosine receptors, but not by nicotinic antagonists. Stage I waves lasted about one day (around embryonic day 22) and then switched rapidly to stage II, resulting in slower and less frequent waves that could be blocked by nicotinic antagonists and had a characteristic postwave refractory period and spatial boundaries between adjacent waves. Immediately after the transition from stage I to stage II, the waves could be reverted back to stage I by blocking nicotinic receptors, indicating the presence of mutually compensatory mechanisms for wave generation. Stage III waves emerged around postnatal day 3–4 (P3–4), and they were mediated by glutamtergic and muscarinic interactions. With age, these waves became weaker, more localized and less frequent. Spontaneous waves were rarely detected after P7. (2) GABA strongly modulated the wave dynamics in a stage‐ and receptor type‐dependent manner. At stage I, endogenous GABAB activation downregulated the waves. The GABAB modulation disappeared during stage II and was replaced by a strong GABAA/C‐mediated inhibition at stage III. Blocking GABAA/C receptors not only dramatically enhanced spontaneous stage III waves, but also induced propagating waves in >P7 retinas that did not show spontaneous waves, indicating a role of GABA inhibition in the disappearance of spontaneous waves. (3) Spontaneous retinal waves were found in both the inner and outer retina at all three stages. The waves in the outer retina (ventricular zone) also showed stage‐dependent pharmacology and dynamics. Together, the results revealed a multistaged developmental sequence and stage‐dependent dynamics, pharmacology and regulation of spontaneous retinal waves in the mammalian retina. The presence of retinal waves during multiple developmental stages and in multiple retinal layers suggests that the waves are a general developmental phenomenon with diverse functions.
Defective respiratory amiloride‐sensitive sodium transport predisposes to pulmonary oedema and delays its resolution in mice
Authors: Egli Marc , Duplain Hervé , Lepori Mattia , Cook Stéphane , Nicod Pascal , Hummler Edith , Sartori Claudio , Scherrer Urs
Published: August 2004

Pulmonary oedema results from an imbalance between the forces driving fluid into the airspace and the biological mechanisms for its removal. In mice lacking the α‐subunit of the amiloride‐sensitive sodium channel (αENaC(−/−)), impaired sodium transport‐mediated lung liquid clearance at birth results in neonatal death. Transgenic expression of αENaC driven by a cytomegalovirus (CMV) promoter (αENaC(−/−)Tg+) rescues the lethal pulmonary phenotype, but only partially restores respiratory sodium transport in vitro. To test whether this may also be true in vivo, and to assess the functional consequences of this defect on experimental pulmonary oedema, we measured respiratory transepithelial potential difference (PD) and alveolar fluid clearance (AFC), and quantified pulmonary oedema during experimental acute lung injury in these mice. Both respiratory PD and AFC were roughly 50% lower (P < 0.01) in αENaC(−/−)Tg+ than in control mice. This impairment was associated with a significantly larger increase of the wet/dry lung weight ratio in αENaC(−/−)Tg+ than in control mice, both after exposure to hyperoxia and thiourea. Moreover, the rate of resolution of thiourea‐induced pulmonary oedema was more than three times slower (P < 0.001) in αENaC(−/−)Tg+ mice. αENaC(−/−)Tg+ mice represent the first model of a constitutively impaired respiratory transepithelial sodium transport, and provide direct evidence that this impairment facilitates pulmonary oedema in conscious freely moving animals. These data in mice strengthen indirect evidence provided by clinical studies, suggesting that defective respiratory transepithelial sodium transport may also facilitate pulmonary oedema in humans.
Distinct profiles of refilling of inhibitory neurotransmitters into presynaptic terminals projecting to spinal neurones in immature rats
Authors: Katsurabayashi Shutaro , Kubota Hisahiko , Higashi Hideho , Akaike Norio , Ito Yushi
Published: August 2004

Corelease of glycine and GABA from the single synaptic terminal (synaptic bouton) is well accepted in immature rat spinal cord and brainstem. However, it raises the question of how glycine and GABA are accumulated in the same synaptic vesicles and coreleased. To address this issue, spontaneous miniature inhibitory postsynaptic currents (mIPSCs) and focally evoked IPSCs (eIPSCs) mediated via a single synapse were recorded from synaptic bouton preparations of the rat immature sacral dorsal commissural nucleus (SDCN) neurones by whole‐cell patch recording. Focal stimulation of a single synaptic bouton revealed that three different quantal releases occur from a single synaptic bouton: i.e. pure glycine, pure GABA, and mixed. Prolonged treatment with bafilomycin A1, a vacuolar‐type H+/ATPase inhibitor, to the SDCN neurone greatly suppressed frequency and amplitude of the mIPSCs. During washing out of bafilomycin A1, complete recovery in the amplitude of glycinergic mIPSCs was observed, while that of GABAergic and mixed mIPSCs was incomplete. These observations indicate that three types of vesicles coexist in single synaptic terminals, and that refilling of glycine into the synaptic vesicle predominantes over GABA after pretreatment with bafilomycin A1 in immature rats. This could be explained by the decrease in the cytosolic concentration of GABA, or by the presence of subtypes of vesicular inhibitory amino acid transporter in the synaptic vesicle membrane.
Mechanisms of hyperpolarization in regenerated mature motor axons in cat
Authors: Moldovan Mihai , Krarup Christian
Published: August 2004

We found persistent abnormalities in the recovery of membrane excitability in long‐term regenerated motor nerve fibres in the cat as indicated in the companion paper. These abnormalities could partly be explained by membrane hyperpolarization. To further investigate this possibility, we compared the changes in excitability in control nerves and long‐term regenerated cat nerves (3–5 years after tibial nerve crush) during manoeuvres known to alter axonal membrane Na+–K+ pump function: polarization, cooling to 20°C, reperfusion after 10 min ischaemia, and up to 60 s of repetitive stimulation at 200 Hz. The abnormalities in excitability of regenerated nerves were reduced by depolarization and cooling and increased by hyperpolarization and during postischaemia. Moreover, the time course of recovery of excitability from repetitive stimulation and ischaemia was prolonged in regenerated nerves. Our data are consistent with an increased demand for electrogenic Na+–K+ pumping in regenerated nerves leading to membrane hyperpolarization. Such persistent hyperpolarization may influence the ability of the axon to compensate for changes in membrane potential following normal repetitive activity.
Presynaptic modulation by neuromedin U of sensory synaptic transmission in rat spinal dorsal horn neurones
Authors: Moriyama Maiko , Furue Hidemasa , Katafuchi Toshihiko , Teranishi Hitoshi , Sato Takahiro , Kano Tatsuhiko , Kojima Masayasu , Yoshimura Megumu
Published: August 2004

Neuromedin U (NMU) is a brain–gut peptide first isolated from the spinal cord. Recent studies on NMU and its receptors have suggested a role of NMU in sensory transmission. Here we report on the localization of NMU in sensory neurones, and the actions of NMU in the substantia gelatinosa (SG) and the deep layer of the dorsal horn (laminae III–V) in adult rat spinal cord slices using the patch‐clamp technique. An immunohistochemical study revealed that NMU peptide was present in most of the dorsal root ganglion neurones. In the spinal cord, NMU‐immunoreactive neurones were located in the deep layer (laminae III–V), but not in the SG. However, NMU‐positive axon terminals were observed in the SG as well as the deep layer. Bath‐applied NMU (10 μm) increased the frequency, but not amplitude, of miniature excitatory postsynaptic currents (mEPSCs) in the SG and deep layer neurones by 146 ± 14% (P < 0.01, n= 17) and 174 ± 21% (P < 0.01, n= 6), respectively, without inducing any postsynaptic membrane currents recorded in tetrodotoxin. On the other hand, NMU did not affect miniature inhibitory postsynaptic currents recorded in tetrodotoxin. These findings, taken together, suggest that NMU acts on the presynaptic terminals of the primary afferent fibres working as an autocrine/paracrine neuromodulator to increase mEPSC frequency of the SG and deep layer neurones. This may account for the spinal mechanisms of the NMU‐induced hyperalgesia reported previously.
Developmental changes in CSF hypocretin‐1 (orexin‐A) levels in normal and genetically narcoleptic Doberman pinschers
Authors: John Joshi , Wu Ming‐Fung , Maidment Nigel T. , Lam Hoa A. , Boehmer Lisa N. , Patton Melanie , Siegel Jerome M.
Published: August 2004

Loss of hypocretin cells or mutation of hypocretin receptors causes narcolepsy. In canine genetic narcolepsy, produced by a mutation of the Hcrtr2 gene, symptoms develop postnatally with symptom onset at 4 weeks of age and maximal symptom severity by 10–32 weeks of age. Canine narcolepsy can readily be quantified. The large size of the dog cerebrospinal fluid (CSF) cerebellomedullary cistern allows the withdrawal of sufficient volumes of CSF for accurate assay of hypocretin levels, as early as postnatal day 4. We have taken advantage of these features to determine the relation of CSF hypocretin levels to symptom onset and compare hypocretin levels in narcoleptic and normal dogs. We find that by 4 days after birth, Hcrtr2 mutants have significantly higher levels of Hcrt than normal age‐ and breed‐matched dogs. These levels were also significantly higher than those in adult narcoleptic and normal dogs. A reduction followed by an increase in Hcrt levels coincides with symptom onset and increase in the narcoleptics. The Hcrtr2 mutation alters the normal developmental course of hypocretin levels.
Stress and glucocorticoid inhibit apical GLUT2‐trafficking and intestinal glucose absorption in rat small intestine
Authors: Shepherd Emma J. , Helliwell Philip A. , Mace Oliver J. , Morgan Emma L. , Patel Nick , Kellett George L.
Published: August 2004

We have proposed a new model of rat intestinal sugar absorption in which high glucose concentrations promote rapid insertion of GLUT2 into the apical membrane, so that absorptive capacity is precisely regulated to match dietary intake. Construction and building work during expansion and refurbishment of our department permitted opportunistic experiments on the effects of building‐induced stress on the GLUT2 component of absorption. In fed rats perfused with 75 mm glucose in vivo, stress rapidly inhibited glucose absorption 36.4 ± 3.0% compared with control rats. Selective inhibition of the GLUT2 component with phloretin demonstrated that stress inhibited the GLUT2 component by 42.8 ± 3.8%, which correlated with a corresponding diminution in apical GLUT2 levels: the SGLT1 component and its level were unaltered by stress. Effects of stress were reversed by the administration in drinking water of metyrapone, which inhibits 11‐β‐hydroxylase. Injection of dexamethasone into control rats 60 min before perfusion resulted in absorption and transporter properties indistinguishable from stressed rats. Our data are consistent with the view that stress activates the hypothalamus–pituitary–adrenal (HPA) axis, causing release of glucocorticoid. The ensuing inhibition of GLUT2 trafficking and absorption seems necessary to prevent enhanced intestinal delivery of glucose to the circulation from antagonizing the essential stress response of glucorticoid in mobilizing peripheral energy stores for emergency purposes.
Interlacing Properties for Mass-Dashpot-Spring Systems With Proportional Damping
Authors: Lin Jong-Lick , Chan Kuo-Chin , Sheen Jyh-Jong , Chen Shin-Ju
Published: August 2004

A mass-dashpot-spring system with proportional damping is considered in this paper. On the basis of an appropriate nonlinear mapping and the root-locus technique, the interlacing property of transmission zeros and poles is investigated if the columns of the input matrix are in the column space generated by the transpose of the output matrix. It is verified that transmission zeros interlace with poles on a specific circle and the nonpositive real axis segments for a proportional damping system. Finally, three examples are given to illustrate the property.
Sensor-Based Estimation and Control of Forces and Moments in Multiple Cooperative Robots
Authors: Kumar Manish , Garg Devendra P.
Published: August 2004

Control of multiple robots presents numerous challenges, some of which include synchronization in terms of position, motion, force, load sharing and internal force minimization. This paper presents formulation and application of a fuzzy logic based strategy for control of two 6 degree-of-freedom robots carrying an object in a cooperative mode. The paper focuses on control of internal forces that get generated when two or more robots carry an object in coordination. Force/torque (F/T) sensors mounted on wrist of each robot provide the force and torque data in six dimensions. A fuzzy logic controller has been designed to use these force/torque (F/T) data to achieve a cooperating movement in which one robot acts as leader and the other robot follows. The paper also deals with estimation of external forces acting on end effector with the use of data provided by F/T sensors. These external forces and moments are not directly measured by F/T sensor since the quantities measured by F/T sensor are corrupted by the dynamics of the end effector and manipulator (a F/T sensor is usually mounted between wrist and end effector of the robot). This paper investigates the use of Kalman filtering technique to extract the external forces acting on robot end effector utilizing the underlying dynamics of the end effector. Matlab’s Fuzzy logic, Simulink, and State Flow toolboxes are used for achieving real-time, autonomous and intelligent behavior of the two robots. Simulation results from two separate experiments show that the above strategy was able to constrain the internal forces and provide a smooth movement of the manipulators.
Signal Conditioning With Memory-Less Nonlinear Sensors
Authors: Suranthiran Sugathevan , Jayasuriya Suhada
Published: August 2004

Proposed in this paper is an off-line signal conditioning scheme for memoryless nonlinear sensors. In most sensor designs, a linear input-output response is desired. However, nonlinearity is present in one form or another in almost all real sensors and therefore it is very difficult if not impossible to achieve a truly linear relationship. Often sensor nonlinearity is considered a disadvantage in sensory systems because it introduces distortion into the system. Due to the lack of efficient techniques to deal with the issues of sensor nonlinearity, primarily nonlinear sensors tend to be ignored. In this paper, it is shown that there are certain advantages of using nonlinear sensors and nonlinear distortion caused by sensor nonlinearity may be effectively compensated. A recursive algorithm utilizing certain characteristics of nonlinear sensor functions is proposed for the compensation of nonlinear distortion and sensor noise removal. A signal recovery algorithm that implements this idea is developed. Not having an accurate sensor model will result in errors and it is shown that the error can be minimized with a proper choice of a convergence accelerator whereby stability of the developed algorithm is established.
Electro-Magnetic-Acoustic Transducers for Automatic Monitoring and Health Assessment of Transmission Lines
Authors: Shoureshi Rahmat A. , Lim Sun-Wook , Dolev Eli , Sarusi Benny
Published: August 2004

This paper presents analysis, design, development, and experimental verification of a non-destructive monitoring system for diagnosis of mechanical integrity of electric conductors based on the concept of Electro-Magnetic-Acoustic Transducers (EMAT). Electric conductors, in general, are exposed to harsh environments. Such conductors include electric transmission lines, anchor rods, and ground mat risers. For automatic failure detection and assessment of mechanical integrity of these conductors, in addition to an effective transducer, feature extraction and pattern recognition techniques have to be employed. Details of the sensor design, neural-based signature analysis, feature extraction, and experimental results of fault detection techniques are presented.
A Self-Energized Sensor for Wireless Injection Mold Cavity Pressure Measurement: Design and Evaluation
Authors: Zhang Li , Theurer Charles B. , Gao Robert X. , Kazmer David O.
Published: August 2004

This paper presents the modeling, design, and experimental validation of a self-energized sensor system for pressure measurement in the injection mold cavity using ultrasound as the information carrier. The sensor extracts energy from the polymer melt pressure and discretizes the pressure information into ultrasonic pulses for wireless transmission through the mold to a remote receiver. Analytical and numerical models are presented for three constituent components of the sensor: the energy converter, the threshold modulator, and the signal transmitter. Quantitative results were obtained to guide the parametric design of each constituent component. Simulations and experimental studies have validated the functionality of each individual component, as well as the sensor as an integrated unit. In addition to the injection mold pressure measurement, the sensing technique developed is applicable in a broad range of process monitoring applications where high pressure fluctuations occur.
A Fresh Insight Into the Microcantilever-Sample Interaction Problem in Non-Contact Atomic Force Microscopy
Authors: Jalili Nader , Dadfarnia Mohsen , Dawson Darren M.
Published: August 2004

The atomic force microscope (AFM) system has evolved into a useful tool for direct measurements of intermolecular forces with atomic-resolution characterization that can be employed in a broad spectrum of applications. The non-contact AFM offers unique advantages over other contemporary scanning probe techniques such as contact AFM and scanning tunneling microscopy, especially when utilized for reliable measurements of soft samples (e.g., biological species). Current AFM imaging techniques are often based on a lumped-parameters model and ordinary differential equation (ODE) representation of the micro-cantilevers coupled with an adhoc method for atomic interaction force estimation (especially in non-contact mode). Since the magnitude of the interaction force lies within the range of nano-Newtons to pica-Newtons, precise estimation of the atomic force is crucial for accurate topographical imaging. In contrast to the previously utilized lumped modeling methods, this paper aims at improving current AFM measurement technique through developing a general distributed-parameters base modeling approach that reveals greater insight into the fundamental characteristics of the microcantilever-sample interaction. For this, the governing equations of motion are derived in the global coordinates via the Hamilton’s Extended Principle. An interaction force identification scheme is then designed based on the original infinite dimensional distributed-parameters system which, in turn, reveals the unmeasurable distance between AFM tip and sample surface. Numerical simulations are provided to support these claims.
Geodesics in the generalized Schwarzschild solution
Authors: Francis Matthew R. , Kosowsky Arthur
Published: August 2004

Since Schwarzshild discovered the point-mass solution to Einstein’s equations that bears his name, many equivalent forms of the metric have been obtained. Using an elementary coordinate transformation, we derive the most general form for the stationary, spherically symmetric vacuum metric, which contains one free function. Different choices for the function correspond to common expressions for the line element. From the general metric, we obtain particle and photon trajectories, and use them to specify several time coordinates adapted to physical situations. The most general form of the metric is only slightly more complicated than the Schwarzschild form, which argues for teaching the general line element in place of the diagonal metric.
Observing the quantum behavior of light in an undergraduate laboratory
Authors: Thorn J. J. , Neel M. S. , Donato V. W. , Bergreen G. S. , Davies R. E. , Beck M.
Published: August 2004

While the classical, wavelike behavior of light (interference and diffraction) has been easily observed in undergraduate laboratories for many years, explicit observation of the quantum nature of light (i.e., photons) is much more difficult. For example, while well-known phenomena such as the photoelectric effect and Compton scattering strongly suggest the existence of photons, they are not definitive proof of their existence. Here we present an experiment, suitable for an undergraduate laboratory, that unequivocally demonstrates the quantum nature of light. Spontaneously downconverted light is incident on a beamsplitter and the outputs are monitored with single-photon counting detectors. We observe a near absence of coincidence counts between the two detectors—a result inconsistent with a classical wave model of light, but consistent with a quantum description in which individual photons are incident on the beamsplitter. More explicitly, we measured the degree of second-order coherence between the outputs to be g(2)(0)=0.0177±0.0026, which violates the classical inequality g(2)(0)⩾1 by 377 standard deviations.
Diffraction from one- and two-dimensional quasicrystalline gratings
Authors: Ferralis N. , Szmodis A. W. , Diehl R. D.
Published: August 2004

The diffraction from one- and two-dimensional aperiodic structures is studied by using Fibonacci and other aperiodic gratings produced by several methods. By examining the laser diffraction patterns obtained from these gratings, the effects of aperiodic order on the diffraction pattern was observed and compared to the diffraction from real quasicrystalline surfaces. The correspondence between diffraction patterns from two-dimensional gratings and from real surfaces is demonstrated.
Mechanical energy and momentum of wave pulses in a dispersionless, lossless elastic medium, according to the linear theory
Authors: Gauthier N. , Rochon P.
Published: August 2004

We re-examine the linear theory of wave propagation through an elastic string under uniform tension or a slender elastic rod from a perspective that focuses on the flow of mechanical energy and mechanical momentum. Continuity equations are established for the flow of energy and momentum, leading to two boundary conditions for the net wave displacement. The important special case of a small amplitude pulse of arbitrary shape traveling through a uniform slender medium joined to another medium with a different linear mass density is examined in detail. The new boundary conditions lead to the correct relative amplitudes for the reflected and transmitted pulses. We obtain the instantaneous mechanical energy and momentum of the incident, reflected, and transmitted pulses and show that the net mechanical energy and momentum are separate constants of motion. The cases of an incoming pulse described by a Lorentzian and a Gaussian distribution are suggested as problems to be solved by the interested reader.
On the quantization of Newton-equivalent Hamiltonians
Authors: Calogero F. , Degasperis A.
Published: August 2004

In classical mechanics, Newton-equivalent Hamiltonians yield the same equations of motion and hence identical dynamics. In the quantum context, they instead generally yield different discrete energy spectra in the confined case and different scattering amplitudes in the unconfined case.