bluuebunny/crossref_metadata_2025 huggingface dataset:
Legs evolved only at the end!
Authors: Fischer Martin S , Witte Hartmut
Published: November 2006

Talking about legged locomotion often evokes the idea that animals using such devices are perfectly adapted to this kind of motion and should be copied by robotics. The aim of this contribution is to show that the evolution of legs comes late in phylogeny, be it in arthropods or vertebrates. Neural control of legs in vertebrates has to deal with conservative arrangements ‘invented’ for axial locomotion of metameric organisms. The structure of this paper is to show the importance of axial driven propulsion in vertebrates without legs, with legs and only at the end how limbs move the body in eutherian mammals.
Honda humanoid robots development
Authors: Hirose Masato , Ogawa Kenichi
Published: November 2006

Honda has been doing research on robotics since 1986 with a focus upon bipedal walking technology. The research started with straight and static walking of the first prototype two-legged robot. Now, the continuous transition from walking in a straight line to making a turn has been achieved with the latest humanoid robot ASIMO. ASIMO is the most advanced robot of Honda so far in the mechanism and the control system. ASIMO's configuration allows it to operate freely in the human living space. It could be of practical help to humans with its ability of five-finger arms as well as its walking function. The target of further development of ASIMO is to develop a robot to improve life in human society. Much development work will be continued both mechanically and electronically, staying true to Honda's ‘challenging spirit’.
Walking: technology and biology
Authors: Pfeiffer Friedrich , Inoue Hirochika
Published: November 2006

If all the signs are to be believed, then the twenty-first century will technologically be characterized by machine walking and its relevant products, which possess all chances to become real bulk goods in the course of the next decades. With several university institutes and with Honda and Sony from the industrial side, Japan is today and without any doubt the leading nation in research and development of walking machines. The US and Europe follow at some distance. Walking machines will influence all areas of daily and industrial life and, with the fast evolution of artificial intelligence, will become a real partner of human beings. All relevant technologies are highly interdisciplinary, they will push the future technologies of all technical fields. The special issue on this topic gives a selection of walking machine research and development including some aspects from biology.
Biologically inspired adaptive walking of a quadruped robot
Authors: Kimura Hiroshi , Fukuoka Yasuhiro , Cohen Avis H
Published: November 2006

We describe here the efforts to induce a quadruped robot to walk with medium-walking speed on irregular terrain based on biological concepts. We propose the necessary conditions for stable dynamic walking on irregular terrain in general, and we design the mechanical and the neural systems by comparing biological concepts with those necessary conditions described in physical terms. PD-controller at joints constructs the virtual spring–damper system as the viscoelasticity model of a muscle. The neural system model consists of a central pattern generator (CPG), reflexes and responses. We validate the effectiveness of the proposed neural system model control using the quadruped robots called ‘Tekken1&2’. MPEG footage of experiments can be seen athttp://www.kimura.is.uec.ac.jp.
Biped walking robots created at Waseda University: WL and WABIAN family
Authors: Lim Hun-ok , Takanishi Atsuo
Published: November 2006

This paper proposes the mechanism and control of the biped humanoid robots WABIAN-RIV and WL-16. WABIAN-RIV has 43 mechanical degrees of freedom (d.f.): 6 d.f. in each leg, 7 d.f. in each arm, 3 d.f. in each hand, 2 d.f. in each eye, 4 d.f. in the neck and 3 d.f. in the waist. Its height is about 1.89 m and its total weight is 127 kg. It has a vision system and a voice recognition system to mimic some of the capabilities of the human senses. WL-16 consists of a pelvis and two legs having six 1 d.f. active linear actuators. An aluminium chair is mounted on two sets of its telescopic poles. To reduce the large support forces during the support phase, a support torque reduction mechanism is developed, which is composed of two compression gas springs with different stiffness. For the stability of the robots, a compensatory motion control algorithm is developed. This control compensates for moments generated by the motion of the lower limbs, using the motion of the trunk and the waist that is obtained by the zero moment point concept and fast Fourier transform. WABIAN-RIV is able to walk forwards, backwards and sideways, dance, carry heavy goods and express emotion, etc. WL-16 can move forwards, backwards and sideways while carrying an adult weighing up to 60 kg.
The experimental humanoid robot H7: a research platform for autonomous behaviour
Authors: Nishiwaki Koichi , Kuffner James , Kagami Satoshi , Inaba Masayuki , Inoue Hirochika
Published: November 2006

This paper gives an overview of the humanoid robot ‘H7’, which was developed over several years as an experimental platform for walking, autonomous behaviour and human interaction research at the University of Tokyo. H7 was designed to be a human-sized robot capable of operating autonomously in indoor environments designed for humans. The hardware is relatively simple to operate and conduct research on, particularly with respect to the hierarchical design of its control architecture. We describe the overall design goals and methodology, along with a summary of its online walking capabilities, autonomous vision-based behaviours and automatic motion planning. We show experimental results obtained by implementations running within a simulation environment as well as on the actual robot hardware.
The TUM walking machines
Authors: Pfeiffer Friedrich
Published: November 2006

This paper presents some aspects of walking machine design with a special emphasis on the three machines MAX, MORITZ and JOHNNIE, having been developed at the Technical University of Munich within the last 20 years. The design of such machines is discussed as an iterative process improving the layout with every iteration. The control concepts are event-driven and follow logical rules, which have largely been transferred from neurobiological findings. At least for the six-legged machine MAX, a nearly perfect autonomy could be achieved, whereas for the biped JOHNNIE, a certain degree of autonomy could be realized by a vision system with appropriate decision algorithms. This vision system was developed by the group of Prof. G. Schmidt, TU-München. A more detailed description of the design and realization is presented for the biped JOHNNIE.
Romantic love: a mammalian brain system for mate choice
Authors: Fisher Helen E , Aron Arthur , Brown Lucy L
Published: November 2006

Mammals and birds regularly express mate preferences and make mate choices. Data on mate choice among mammals suggest that this behavioural ‘attraction system’ is associated with dopaminergic reward pathways in the brain. It has been proposed that intense romantic love, a human cross-cultural universal, is a developed form of this attraction system. To begin to determine the neural mechanisms associated with romantic attraction in humans, we used functional magnetic resonance imaging (fMRI) to study 17 people who were intensely ‘in love’. Activation specific to the beloved occurred in the brainstem right ventral tegmental area and right postero-dorsal body of the caudate nucleus. These and other results suggest that dopaminergic reward and motivation pathways contribute to aspects of romantic love. We also used fMRI to study 15 men and women who had just been rejected in love. Preliminary analysis showed activity specific to the beloved in related regions of the reward system associated with monetary gambling for uncertain large gains and losses, and in regions of the lateral orbitofrontal cortex associated with theory of mind, obsessive/compulsive behaviours and controlling anger. These data contribute to our view that romantic love is one of the three primary brain systems that evolved in avian and mammalian species to direct reproduction. The sex drive evolved to motivate individuals to seek a range of mating partners; attraction evolved to motivate individuals to prefer and pursue specific partners; and attachment evolved to motivate individuals to remain together long enough to complete species-specific parenting duties. These three behavioural repertoires appear to be based on brain systems that are largely distinct yet interrelated, and they interact in specific ways to orchestrate reproduction, using both hormones and monoamines. Romantic attraction in humans and its antecedent in other mammalian species play a primary role: this neural mechanism motivates individuals to focus their courtship energy on specific others, thereby conserving valuable time and metabolic energy, and facilitating mate choice.
Effectiveness of a smoking cessation intervention in older adults
Authors: Tait Robert J. , Hulse Gary K. , Waterreus Anna , Flicker Leon , Lautenschlager Nicola T. , Jamrozik Konrad , Almeida Osvaldo P.
Published: November 2006

Aims  To: (a) identify characteristics of older smokers considering cessation of smoking; (b) evaluate a cessation intervention plus access to nicotine replacement therapy (NRT); (c) identify predictors of those who successfully quit; and (d) evaluate the effectiveness of the intervention in those aged ≥ 75 years.

Design  Self‐selection of: (a) a cessation of smoking programme; or (b) ongoing smoking.

Setting  Teaching hospital, Perth, Western Australia.

Participants  A larger study recruited smokers and never smokers: from this the 215 community‐dwelling smokers (≥ 5 cigarettes/day) aged ≥ 68 years (171 males) were enrolled.

Intervention  Brief intervention with telephone support and access to NRT versus no intervention.

Measurements  (a) Profile of older adults planning to quit smoking compared with continuing smokers; (b) cessation at 6 months defined as 30‐day point prevalence validated via expired carbon monoxide; and (c) factors predictive of successful cessation.

Findings  There were 165 intervention participants. Compared with the 50 continuing smokers, participants in the intervention were younger and had significantly less years of regular smoking, more previous quit attempts and greater nicotine dependence scores. At 6 months, the point prevalence of ex‐smokers was 25% (n = 42) with 20% (n = 33) being abstinent throughout the study. No continuing smoker had ceased smoking. Among the intervention group, logistic regression showed that those who used NRT (OR 4.36), were male (OR 3.17), had higher anxiety (OR 1.67) or rejected ‘more colds and coughs’ as a reason for quitting (OR 2.91) were more likely to be successful quitters. Of those aged ≥ 75 years (n = 77), 25% matched cessation criteria.

Conclusions  Older smokers can be engaged successfully in a brief intervention plus NRT as aids to cessation of smoking. The intervention was also effective in the older subgroup of participants. Social factors may provide an additional means of motivating older smokers to quit.
Clinical assessment and molecular analysis of GnRHR and KAL1 genes in males with idiopathic hypogonadotrophic hypogonadism
Authors: Versiani Beatriz R. , Trarbach Ericka , Koenigkam‐Santos Marcel , Dos Santos Antonio Carlos , Elias Lucila L. K. , Moreira Ayrton C. , Latronico Ana Claudia , De Castro Margaret
Published: November 2006

Objective  The pathogenesis of idiopathic hypogonadotrophic hypogonadism (IHH) is mostly unclear. We characterized the clinical findings and molecular analysis of GnRHR and KAL1 genes in 26 Brazilian males with IHH with and without hyposmia/anosmia.

Design  Clinical assessment was performed for endocrine status, olfactory structure and function, renal lesion, and mirror movement. The diagnosis of Kallmann syndrome (KS) included HH and the clinical complaint of hyposmia/anosmia or decreased olfactory acuity obtained by the Smell Identification Test™ (SIT). We analysed GnRHR and KAL1 genes using the polymerase chain reaction (PCR) direct sequencing method.

Results  A variable degree of HH was observed, including various clinical abnormalities, such as cryptorchidism, hearing loss, strabismus, cleft lip/palate, high‐arched palate, dental agenesis, psychiatric disorders, learning dysfunction, and bimanual synkinesia. Twenty‐two out of 26 patients with IHH (85%) were classified as KS. Abnormalities of olfactory bulbs/sulci were observed in 79% of KS patients. One‐third of KS patients had renal defects and 45·5% had a positive family history. GnRHR gene sequence analysis showed no mutations. KAL1 sequence analysis identified two novel missense mutations: c.1061A to G in exon 7 (N304S) and c.1583C to A in exon 10 (S478X). We also observed a 14‐bp deletion within exon 11 that caused a premature termination. According to the National Center for Biotechnology Information (NCBI)‐Single Nucleotide Polymorphism (SNP) database, two previously described polymorphisms (rs808119 and rs809446) were detected.

Conclusion  KAL1 mutations accounted for 12% of KS patients. This low prevalence of KAL1 mutations indicates that other genes, such as the fibroblast growth factor receptor 1 (FGFR1) gene or other as yet undiscovered genes, epigenetic events and/or environmental factors might be involved in the aetiology and phenotypic variability of KS.
Re‐establishment of local populations of vectors of Chagas disease after insecticide spraying
Authors: ZU DOHNA HEINRICH , CECERE MARÍA C. , GÜRTLER RICARDO E. , KITRON URIEL , COHEN JOEL E.
Published: November 2006

Prevention of Chagas disease is mainly dependent on control of the insect vectors that transmit infection. Unfortunately, this control is not wholly successful and the vectors have been resurgent in some areas. Where re‐infestation has occurred, it is important to understand the dynamics of the process. We investigated how a metapopulation framework can elucidate key aspects of re‐infestation and thereby contribute to more efficient disease control.

Triatoma infestans, the main vector of Chagas disease, re‐infested sites in three villages in north‐west Argentina after community‐wide insecticide spraying in October 1992. Ten surveys were carried out at 6‐monthly intervals from November 1994 to May 1999.

Comparisons were made of different methods of estimating the sources of dispersal and the number of sites in which bug infestations became established.

The results indicated that (i) the number of dispersing Triatoma infestans from a given site was proportional to the number of bugs found at the site; (ii) there was a 6‐month time lag between detection of a new infestation and dispersal events; (iii) the relationship between infestations and new establishments varied by season.

Three of 156 sites at which bugs were found were estimated to be the source of more than 50% of establishment events. These three sites were the only ones with large, persistent bug populations.

Synthesis and applications. To reduce the risk of human Chagas disease, identifying those few sites infested with large, persistent bug populations and targeting control measures at those sites should greatly improve the efficiency of vector control. The appropriate seasonal timing of vector control could also greatly increase its efficiency. Specific recommendations for the timing of insecticide spraying require further research to establish how the observed temporal pattern of bug establishment is associated with the seasonality of bug dispersal.
Mechanisms driving avoidance of non‐native plants by lizards
Authors: VALENTINE LEONIE E. , ROBERTS BRADY , SCHWARZKOPF LIN
Published: November 2006

Introduced plant species modify the environment and alter ecological interactions in communities, often to the detriment of native fauna, but the causes driving negative effects on fauna are rarely examined. We used native Australian scincid lizards Carlia munda and Carlia pectoralis and the introduced weed rubber vine Cryptostegia grandiflora as a model system to determine the possible underlying mechanisms driving habitat selection by native fauna in an environment invaded by weeds.

Lizards were allowed to select between rubber vine and native eucalypt leaf litter in semi‐natural enclosures. To determine the mechanisms of habitat preference, we examined differences in temperature, prey (arthropod) availability and composition, and leaf shape of naturally occurring rubber vine and native vegetation.

Lizards discriminated between leaf litter types: 85% of Carlia pectoralis and 80% of Carlia munda chose native leaf litter over rubber vine, clearly indicating a preference for native habitat.

In the field, rubber vine leaf litter was cooler at the surface than native leaf litter, and during peak lizard activity was below the temperature range of Carlia. Rubber vine also contained significantly fewer arthropod taxa and a significantly different composition of arthropod taxa, with fewer preferred prey items of Carlia than native vegetation.

Finally, rubber vine leaves were significantly shorter than native leaves and the lizards themselves. The shape of rubber vine leaves was different from that of the lizards, potentially making the lizards more obvious on rubber vine litter. This may increase the susceptibility of the lizards to detection by predators.

Synthesis and applications. In comparison with native habitat, rubber vine provided a suboptimal environment for litter‐dwelling lizards because of the lower ambient temperatures, reduced availability of prey and a reduction in camouflage from predators (dissimilar leaf and lizard shapes). Our study has identified three possible mechanisms by which an introduced plant species can alter the availability of resources in an environment, making it less attractive to native fauna. Our results highlight the importance of understanding how alien plants alter the environment and further emphasize the critical need for management of plants that replace native habitat with a suboptimal environment.
Peptide anchoring spore coat assembly to the outer forespore membrane in Bacillus subtilis
Authors: Ramamurthi Kumaran S. , Clapham Katie Rose , Losick Richard
Published: November 2006

Spore formation in Bacillus subtilis involves the formation of a thick, proteinaceous shell or coat that is assembled around a specialized membrane known as the outer forespore membrane. Here we present evidence that the assembling coat is tethered to the outer forespore membrane by a 26‐amino‐acid peptide called SpoVM, which is believed to form an amphipathic helix. We show that proper localization of SpoVM is dependent on SpoIVA, a morphogenetic protein that forms the basement layer of the spore coat, and conversely, that proper localization of SpoIVA is dependent on SpoVM. Genetic, biochemical and cytological evidence indicates that this mutual dependence is mediated in part by contact between an amino acid side‐chain located near the extreme C‐terminus of SpoIVA and an amino acid side‐chain on the hydrophilic face of the SpoVM helix. Evidence is also presented that SpoVM adheres to the outer forespore membrane via hydrophobic, amino acid side‐chains on the hydrophobic face of the helix. The results suggest that the SpoVM helix is oriented parallel to the membrane with the hydrophobic face buried in the lipid bilayer.
Dimeric structure of the cell shape protein MreC and its functional implications
Authors: Van Den Ent Fusinita , Leaver Mark , Bendezu Felipe , Errington Jeff , De Boer Piet , Löwe Jan
Published: November 2006

The bacterial actin homologue MreB forms helical filaments in the cytoplasm of rod‐shaped bacteria where it helps maintain the shape of the cell. MreB is co‐transcribed with mreC that encodes a bitopic membrane protein with a major periplasmic domain. Like MreB, MreC is localized in a helical pattern and might be involved in the spatial organization of the peptidoglycan synthesis machinery. Here, we present the structure of the major, periplasmic part of MreC from Listeria monocytogenes at 2.5 Å resolution. MreC forms a dimer through an intimate contact along an N‐terminal α‐helix that connects the transmembrane region with two C‐terminal β‐domains. The translational relationship between the molecules enables, in principle, filament formation. One of the β‐domains shows structural similarity to the chymotrypsin family of proteins and possesses a highly conserved Thr Ser dipeptide. Unexpectedly, mutagenesis studies show that the dipeptide is dispensable for maintaining cell shape and viability in both Escherichia coli and Bacillus subtilis. Bacterial two‐hybrid experiments reveal that MreC interacts with high‐molecular‐weight penicillin‐binding proteins (PBPs), rather than with low‐molecular‐weight endo‐ and carboxypeptidases, indicating that MreC might act as a scaffold to which the murein synthases are recruited in order to spatially organize the synthesis of new cell wall material. Deletion analyses indicate which domains of B. subtilis MreC are required for interaction with MreD as well as with the PBPs.
In vivorecovery and survival of red cells after photodynamic treatment with thiopyrylium and red light using a canine model
Authors: Skripchenko A. , Balch A. , Mackin A. , Wagner S. J.
Published: November 2006

Recently, we have shown that thiopyrylium has robust inactivation capabilities against a broad spectrum of pathogens in the human red blood cell (RBC) suspensions while retaining key RBCin vitroproperties. The 24‐h recovery and survival of canine red cells were measured upon autologus reinfusion of control and phototreated units. The 24‐h recovery of control and phototreated RBCs was 75.7 ± 6.4% and 87.5 ± 8.5%, respectively. The time for 50% survival of labelled control RBCs was similar to that of phototreated group (206 ± 58 h vs. 255 ± 63 h, respectively). Results suggest that thiopyrylium phototreatment does not negatively affect canine RBCin vivorecovery.
Hajdu‐Cheney syndrome: Report of a family and a short literature review
Authors: Marik I , Kuklik M , Zemkowa D , Kozlowski K
Published: November 2006

We report three members of an Armenian family with Hajdu‐Cheney syndrome. The history suggested that five other members of the family were also probably affected. This disorder is important for the radiologist because distinctive radiographic findings make the diagnosis possible before clinical signs and symptoms are fully developed. Additionally, radiographic examination is essential in all patients suspected of Hajdu‐Cheney syndrome for confirmation of the clinical diagnosis. Radiographic examination also detects complications of the syndrome not evident on clinical examination.
Usefulness of scintimammography as an adjunct to mammography and ultrasound in the diagnosis of breast diseases
Authors: Gupta R , Collier D , Abdeen S , Roberts L , Hussein AYT , Al‐Bader I , Syed GM
Published: November 2006

This study was undertaken to evaluate the diagnostic efficacy of 99mtechnetium methoxyisobutylisonitrile scintimammography (SM) and combined use of mammography and ultrasound in the detection of the breast lesions in the symptomatic breast. Histopathological findings were the gold standard. Eighty patients with symptomatic breasts underwent mammography and/or ultrasound breast followed by SM. In 25 patients there were 27 lesions that were malignant and 55 patients had 65 lesions that were benign. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of SM were found to be 92, 72, 58, 96 and 78%, respectively, as compared with the combined use of mammography and ultrasound, which showed these parameters to be 89, 94, 86, 95 and 92%, respectively. In this study, SM showed slightly better sensitivity than combined mammography and ultrasound, whereas the specificity was clearly shown as higher in the latter.
Assessment of future remnant liver regeneration after portal vein embolization using three‐dimensional CT and MR volumetric analyses
Authors: Zacharia TT
Published: November 2006

The purpose of this study is to portray right portal vein embolization (PVE) as a valuable technique that helps in expanding the volume of the left liver lobe and discuss the relevant published work. We describe our experience with four patients who underwent PVE and analyse the value of CT and MRI in the preoperative evaluation of these patients. Four patients with hepatic malignancy (hepatocellular carcinoma) (n = 2) and metastatic liver disease (n = 2) underwent portal vein occlusion. PVE was carried out in three patients using polyvinyl alcohol and stainless steel coils. Portal vein ligation was carried out in the fourth patient. In patients who were candidates for right hepatectomy, CT volumetric analysis was carried out before the surgery to assess the total liver volume and the future remnant liver, which is the residual left hepatic volume (in cases of right hepatectomy) or left lateral segment volume (in cases of right tri‐segmentectomy). Because the left lobe volumes were insufficient, patients were selected to undergo right PVE. Computed tomography volumetry was carried out 2–4 weeks after embolization to assess left hepatic lobe regeneration. Magnetic resonance volumetric analysis was carried out in two patients before and after embolization. All four patients had significant regeneration of the left lobe and tolerated the surgery with uneventful postoperative recovery.
Recognition and management of contrast media extravasation
Authors: Sum W , Ridley LJ
Published: November 2006

Intravenous contrast agents are frequent adjuncts used in diagnostic imaging. Despite the well‐recognized complications of contrast media extravasation, its treatment remains an enigma to many. This article reviews the recognition, prevention and treatment options, with a summary of the contrast media extravasation policy implemented in our department.
Intra‐articular fibrous band of the ankle: An uncommon cause of post‐traumatic ankle pain
Authors: Slavotinek JP , Zadow S , Martin DK
Published: November 2006

A case of an intra‐articular fibrous band of the ankle is presented with emphasis on the MR imaging appearances. This entity is an important but uncommon cause of post‐traumatic ankle pain and is well recognized within the arthroscopy literature, but there is little if any documentation of this condition in the imaging literature.
Can an evidence‐based guideline reduce unnecessary imaging of road trauma patients with cervical spine injury in the emergency department?
Authors: Goergen SK , Fong C. , Dalziel K , Fennessy G
Published: November 2006

The aim of this study was to determine if an unvalidated imaging guideline can reduce the use of imaging in patients with cervical spine trauma. A non‐randomized clinical trial using historical controls was conducted in the emergency department from October 2001 to September 2002. Following an education programme, which introduced the imaging guideline to clinicians, the use of guideline and imaging were measured. The guideline was also converted to decision‐support software for use in the emergency department. Three hundred and fifty‐three patients satisfied inclusion criteria during the study period and these were compared with 403 historical control subjects. No significant difference was found between the two groups for age, sex or fracture prevalence. A significant increase was observed during the study period in the proportion of patients who were managed without the use of any cervical spine imaging (21.25 vs 31.2%; P = 0.03; 95% confidence interval, 3–13). There were no delayed diagnoses of cervical spine injury among those not imaged. It is feasible to disseminate and implement an evidence‐based imaging guideline for patients with cervical spine trauma. The use of a computerized decision‐support system can facilitate this and is associated with a safe reduction in the proportion of patients imaged.
Evaluation of fibre bridging stress of short fatigue cracks in SCS‐6/Ti‐15‐3 composite
Authors: AKINIWA Y. , FUJII T. , KIMURA H. , TANAKA K.
Published: November 2006

Single‐edge notched specimens of a unidirectional SiC long fibre reinforced titanium alloy, were fatigued under four point bending. The propagation behaviour of short fatigue cracks from a notch was observed on the basis of the effects of fibre bridging. The branched fatigue cracks were initiated from the notch root. The fatigue cracks propagated only in the matrix and without fibre breakage. The crack propagation rate decreased with crack extension due to the crack bridging by reinforced fibres.

After fatigue testing the loading and residual stresses in the reinforced fibres were measured for the arrested cracks by the X‐ray diffraction method. The longitudinal stresses in the reinforced fibres were measured using high spatial resolution synchrotron radiation. A stress map around the fatigue cracks was then successfully constructed. The longitudinal stress decreased linearly with increasing distance from a location adjacent to the wake of the matrix crack. This region of decreasing stress corresponded to the debonding area between the fibre and the matrix. The interfacial frictional stress between the matrix and the fibre could be determined from the fibre stresses. The bridging stress on the crack wake was also measured as a function of a distance from a notch root. The threshold stress intensity factor range, corrected on the basis of the shielding stress, was similar to the propagation behaviour of the monolithic matrix. Hence the main factor influencing the shielding effect in composites is fibre bridging.
Bidirectional regulation of dopamine D2 and neurotensin NTS1 receptors in dopamine neurons
Authors: Jomphe C. , Lemelin P.‐L. , Okano H. , Kobayashi K. , Trudeau L.‐E.
Published: November 2006

Several lines of evidence suggest a close association between dopamine (DA) and neurotensin (NT) systems in the CNS. Indeed, in the rodent brain, abundant NT‐containing fibres are found in DA‐rich areas such as the ventral tegmental area and substantia nigra. Moreover, it has been shownin vivothat NT, acting through its high‐affinity receptor (NTS1), reduces the physiological and behavioural effects of DA D2 receptor (D2R) activation, a critical autoreceptor feedback system regulating DA neurotransmission. However, the mechanism of this interaction is still elusive. The aim of our study was thus to reproducein vitrothe interaction between D2R and NTS1, and then to characterize the mechanisms implicated. We used a primary culture model of DA neurons prepared from transgenic mice expressing green fluorescent protein under the control of the tyrosine hydroxylase promoter. In these cultures, DA neurons endogenously express both D2R and NTS1. Using electrophysiological recordings, we show that activation of D2R directly inhibits the firing rate of DA neurons. In addition, we find that NT, acting through a NTS1‐like receptor, is able to reduce D2R autoreceptor function independently of its ability to enhance DA neuron firing, and that this interaction occurs through a protein kinase C‐ and Ca2+‐dependent mechanism. Furthermore, prior activation of D2R reduces the ability of NTS1 to induce intracellular Ca2+mobilization. Our findings provide evidence for bidirectional interaction between D2R and NTS1 in DA neurons, a regulatory mechanism that could play a key role in the control of the activity of these neurons.
Isolation rearing induces recognition memory deficits accompanied by cytoskeletal alterations in rat hippocampus
Authors: Bianchi M. , Fone K. F. C. , Azmi N. , Heidbreder C. A. , Hagan J. J. , Marsden C. A.
Published: November 2006

Social isolation from weaning affects hippocampal structure and function in the rat. The intrinsic dynamic instability of the cytoskeletal microtubular system is essential for neuronal development and organization. Accordingly, the present paper investigated the effects of social isolation on hippocampal levels of α‐tubulin isoforms associated with microtubule dynamics, the dendritic marker MAP‐2 and alterations in locomotor activity and recognition memory. Male Lister Hooded rats (postnatal day 25–28) were housed either in groups or singly (isolated animals) for 30 days. Locomotor activity in a novel arena and novel object recognition were monitored in activity boxes. The hippocampus was dissected out 18 h after the novel object recognition task. Levels of α‐tubulin isoforms and MAP‐2 were analysed using Western blots. The experiments were conducted in duplicate, using two batches of rats obtained from different suppliers. Isolated animals were hyperactive and showed recognition memory deficits in the novel object recognition task. These behavioural alterations were accompanied by specific alterations in hippocampal α‐tubulin isoforms and decreased MAP‐2 expression. The results confirm that rearing rats in isolation produces hyperactivity and cognitive deficits. The behavioural alterations were accompanied by hippocampal cytoskeletal changes consistent with microtubule stabilization, and by decreased MAP‐2 expression. These findings are indicative of an abnormal development of synaptic connections and/or reductions in neuronal cell number. The developmental structural abnormalities in the hippocampus may contribute to the cognitive impairments which result from isolation rearing in rats.
The effectiveness of ARNDT endobronchial blockers in paediatric scoliosis surgery
Authors: Bird G.T. , Nel L. , Hall M. , Davies E. , Ross O.
Published: November 2006

Introduction:  Although described for paediatric thoracic surgery (1), there is little data on the use of the Arndt endobronchial blocker in paediatric spinal deformity surgery. We present its successful application in these patients.

Methods:  Thirteen patients undergoing surgical correction of scoliosis involving a lateral thoracotomy anterior approach were suitable for lung isolation using an Arndt endobronchial blocker. Placement was via an armoured tracheal tube; the endobronchial blockers were 5 or 9 FG with low‐volume low‐pressure cuffs (spherical or elliptical balloons). Placement was by a paediatric anaesthetist trained in paediatric bronchoscopy and required a 2.2 or a 2.8 mm paediatric fibreoptic bronchoscope.

Results:  Patient ages ranged from 18 months to 18 years and weights from 9 kg to 71 kg. All had idiopathic or congenital scoliosis; one patient underwent a VEPTR procedure. In all 13 patients, placement was easily and promptly achieved with no incorrect placements, displacements (including after patient repositioning), or failures to isolate one lung. Median time of insertion was 5 min (with checks), speed of insertion increasing as experience improved. Inflation times for the blocker balloon ranged from 1.5 h to 5 h. There was no airway trauma; direct bronchial inspection revealed local erythema only. Saturations were supported with 5 cm CPAP to the isolated lung and one‐lung ventilation was well tolerated in all but one patient with acceptable airway pressures (<35 cm water); this one patient required partial lung inflation (blocker in place, balloon not inflated) to maintain adequate saturations and airway pressures. The surgical field was excellent in all cases.

Discussion:  Complex paediatric spinal surgery may require lung collapse to improve spinal access, and is traditionally achieved using a double‐lumen tracheal tube. Difficulties can arise as the children are often small for age with potentially distorted airway anatomy and there are a limited number of double lumen tube sizes. This can lead to inadequate isolation, a poor surgical field, endobronchial cuff herniation or obstruction of left upper lobe (tube too small or too long). The careful use of the Arndt endobronchial blocker avoids all these problems and enables easy reliable and safe isolation. Potential complications include malposition, migration, and direct airway trauma, allied to the usual complications of one lung anaesthesia. In our series, there were no complications relating to its use and insertion was quick and straightforward.

Conclusions:  Lung isolation with the Arndt endobronchial blocker is both safe and very effective in paediatric spinal deformity surgery.

Reference  1 Wald SH, Mahajan A, Kaplan MB et al. Experience with the Arndt paediatric bronchial blocker. Br J Anaesth 2005; 94: 92–94.
Development of Computer‐Based System for the Temperature Monitoring of a Post‐Tensioned Segmental Concrete Box‐Girder Bridge
Authors: Mondal Paramita , DeWolf John T.
Published: November 2006

Abstract:  This article describes the development and implementation of a computer‐based remote monitoring system for the temperature monitoring of an 11 span segmental, post‐tensioned concrete box‐girder bridge. Monitoring has been carried out for 5 years. The extensive data collected is analyzed using software that has been developed to provide engineers with information that can be used in the evaluation of the long‐term behavior and performance of the bridge. The software has been used to determine the maximum and the minimum bridge temperatures, the vertical temperature differences through the bridge cross section, and the horizontal temperature differences in the transverse directions. Comparisons have been made with design specification provisions and with recommendations proposed by previous researchers. In addition, software has been developed to determine the relationship between the daily maximum temperature differences and the air temperatures inside the box‐girder. This approach is also used to develop the relationship between the maximum stresses due to temperature differences and the air temperature inside the box‐girder. This article shows the benefits from using a computer‐based monitoring system to provide a continuous evaluation of data collected on the bridge.
A Parallel Ant Colony Algorithm for Bus Network Optimization
Authors: Yang Zhongzhen , Yu Bin , Cheng Chuntian
Published: November 2006

Abstract: This study presents an optimization model for a bus network design based on the coarse‐grain parallel ant colony algorithm (CPACA). It aims to maximize the number of direct travelers per unit length, that is, direct traveler density, subject to route length and nonlinear rate constraints (ratio of the length of a route to the shortest road distance between the origin and destination). CPACA is a new optimal algorithm that (1) develops a new strategy to update the increased pheromone, called Ant‐Weight, by which the path‐searching activities of ants are adjusted based on the objective function, and (2) uses parallelization strategies of an ant colony algorithm (ACA) to improve the calculation time and the quality of the optimization. Data collected in Dalian City, China, are used to test the model and the algorithm. The results show that the optimized bus network has significantly reduced transfers and travel time. They also reveal that the proposed CPACA is effective and efficient compared to some existing ant algorithms.
A JEWISH CONCEPTION OF HUMAN DIGNITY
Authors: Shultziner Doron
Published: November 2006

This paper depicts the meanings of human dignity as they unfold and evolve in the Bible and the Halakhah. I posit that three distinct features of a Jewish conception of human dignity can be identified in contrast to core characteristics of a liberal conception of human dignity. First, the original source of human dignity is not intrinsic to the human being but extrinsic, namely in God. Second, it is argued that the “dignity of the people” has precedence over personal autonomy and liberty, which are core liberal pillars. The third characteristic pertains to the potential conflict between personal autonomy and liberty, and God's commandments. The theoretical analysis of human dignity is then examined in light of several Supreme Court decisions in Israel during the 1990s. I illustrate that Jewish religious and secular‐liberal conceptions pull in different directions in the rulings of liberal and religious Justices in Israel.
THE ETHICS OF LAND RESTITUTION
Authors: Vorster Jakobus M.
Published: November 2006

Many indigenous communities were dispossessed of their land during the period of colonial rule. This long process resulted in forced demographic removals and perennial poverty. Nowadays these communities, especially Third World groups, seek redress of this situation through legal processes of land restitution. This process is met by resistance from landowners in these countries, the colonial powers of old, as well as from big corporations that benefited from the dispossession. The investigation undertaken in this article addresses the ethics of land reform from a Christian ethical perspective. The policy of land restitution in South Africa is used as a case study, but the results of this research are also applicable to other parts of the world where land restitution is considered. The article first evaluates the biblical teachings of land and land reform and their implications for modern ethics. In the light of these issues, the article addresses the question of whether land ownership can be considered as a fundamental human right. The article also focuses on the legality of expropriation and dispossession of land for the purposes of restitution. Moreover, guidelines for fair and legal restitution within the context of Christian ethics and legal philosophical principles are proposed.
An update on Behçet's disease
Authors: Kalayciyan A , Zouboulis CC
Published: November 2006

Behçet's disease (Adamantiades‐Behçet's disease, ABD) is a multisystemic inflammatory disease, the pathogenesis of which is still a mystery. Many questions are still to be answered and the available diverse data need to be brought together to be compared and analysed. There is at least consensus on the effect of possible, but currently unknown, environmental triggering factor(s) against a background of genetic susceptibility. The possible aetiological factors form a broad spectrum, with infectious agents being the most probable ones. Whatever the stimulus is, the target tissue seems to be the small blood vessels, with various consequences of either vasculitis and/or thrombosis in many organ systems. The endothelium seems to be the primary target in this disease; however, it may just be the subject of the bizarre behaviour of the immune system. The diverse existing data could be interpreted in favour of either explanation. A similar confusion exists about the thrombotic tendency in Adamantiades‐Behçet's disease, in terms of whether a primary hypercoagulability is present or whether it is secondary to inflammation. Recent interesting immunological data promise a way out of the existing dilemma. These findings will be outlined within the context of possible hypotheses and attention will be paid to further investigations that are needed.
Lack of association between leptin G2548A gene polymorphism and Behçet's disease
Authors: Aydin F , Kara N , Senturk N , Gunes S , Canturk MT , Bagci H , Bek Y , Turanli AY
Published: November 2006

Background  Behçet's disease is a chronic, multisystem, inflammatory disease characterized by the predominance of T‐helper 1 cytokines. The disease is also characterized by infiltration of lymphocytes and neutrophils into the affected tissues. Because cytokines are involved in the regulation of lymphocyte and phagocyte functions, they may play an important role in the pathogenesis of Behçet's disease. Leptin, a member of the gp 130 family of cytokines, induces a strong T‐helper 1 response and is regarded as a proinflammatory inducer. Recent studies have shown that serum leptin concentration was increased in patients with Behçet's disease and correlated with disease activity.

Objectives  We aimed to investigate the role of G2548A polymorphism of leptin gene in patients with Behçet's disease and compare the results with healthy controls.

Patients and methods  A total of 93 subjects with Behçet's disease and 125 healthy controls were included in this study. Analyses of G‐2548A polymorphism of the LEP gene were performed using the PCR‐restriction fragment length polymorphism technique. The genotypes (GG, GA, and AA of leptin G2548A) and alleles (G and A of leptin 2548) were scored and the frequency was estimated. The frequencies of the alleles and genotypes in patients and controls were compared. We analysed the correlation between leptin gene polymorphism and the clinical features of BD.

Results  Both genotype and allele frequencies were not significantly different between controls and Behçet's disease patients [OR = 0.67, 95% CI (0.35–1.29), P = 0.197 and OR = 0.77, 95% CI (0.52–1.15), P = 0.184]. We did not find any significant relationship between leptin gene polymorphism and the clinical features of BD (P > 0.05).

Conclusion  In the present case‐control study, we found no evidence of an association between the G‐2548A variant of the leptin gene and BD among Turks. Further studies are needed to investigate serum leptin level to explain the mechanisms behind the lack of association between leptin G2548A gene polymorphism and BD.
Efficacy and safety of long‐term treatment with cyclosporin A for atopic dermatitis
Authors: Hijnen DJ , Ten Berge O , Timmer‐de Mik L , Bruijnzeel‐Koomen CAFM , De Bruin‐Weller MS
Published: November 2006

Background  Cyclosporin A (CsA) is being increasingly used in the treatment of severe refractory atopic dermatitis. Clinical efficacy and safety of short‐term cyclosporin A treatment in atopic dermatitis patients has been proven, however, data on long‐term treatment are limited.

Objective  The aim of this study was to investigate the efficacy, safety and the effect of discontinuation of cyclosporin A treatment in atopic dermatitis patients, with a particular focus on patients treated with cyclosporin A for more than 6 months.

Methods  We performed a retrospective study of clinical and adverse effects of cyclosporin A treatment in 73 atopic dermatitis patients, with an average duration of cyclosporin A treatment of 1.3 years.

Results  We included 73 patients (31 women and 42 men, with a mean age of 33.8 years) with severe atopic dermatitis refractory to conventional therapy that was treated with cyclosporin A. Treatment was successful in 56/73 patients. Increases in serum creatinine levels > 30% compared to baseline were reported in 7/73 patients. Arterial hypertension appeared in 11/73 patients during treatment. After discontinuation of treatment, 40/73 patients experienced a relapse and 33/73 patients experienced clinical remission for at least 3 months. No correlation between treatment duration and nephrotoxicity or hypertension was found. Strikingly, 6/73 patients experienced a rebound phenomenon.

Conclusions  We conclude that CsA is an effective and safe treatment for patients with severe AD refractory to conventional treatment, provided that the recommended guidelines for its administration are strictly observed. However, in contrast to previous reports, we found that 8% (6/73) of patients experienced a rebound phenomenon after discontinuation of treatment.