bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular and clinical analyses of 84 patients with tuberous sclerosis complex
Authors: Hung Chia-Cheng , Su Yi-Ning , Chien Shu-Chin , Liou Horng-Huei , Chen Chih-Chuan , Chen Pau-Chung , Hsieh Chia-Jung , Chen Chih-Ping , Lee Wang-Tso , Lin Win-Li , Lee Chien-Nan 
Published: September 2006

Abstract

Background
Tuberous sclerosis complex (TSC) is an autosomal dominant disease characterized by the development of multiple hamartomas in many internal organs. Mutations in either one of 2 genes, TSC1 and TSC2, have been attributed to the development of TSC. More than two-thirds of TSC patients are sporadic cases, and a wide variety of mutations in the coding region of the TSC1 and TSC2 genes have been reported.

Methods
Mutational analysis of TSC1 and TSC2 genes was performed in 84 Taiwanese TSC families using denaturing high-performance liquid chromatography (DHPLC) and direct sequencing.

Results
Mutations were identified in a total of 64 (76 %) cases, including 9 TSC1 mutations (7 sporadic and 2 familial cases) and 55 TSC2 mutations (47 sporadic and 8 familial cases). Thirty-one of the 64 mutations found have not been described previously. The phenotype association is consistent with findings from other large studies, showing that disease resulting from mutations to TSC1 is less severe than disease due to TSC2 mutation.

Conclusion
This study provides a representative picture of the distribution of mutations of the TSC1 and TSC2 genes in clinically ascertained TSC cases in the Taiwanese population. Although nearly half of the mutations identified were novel, the kinds and distribution of mutation were not different in this population compared to that seen in larger European and American studies.
Changes in aortic blood flow induced by passive leg raising predict fluid responsiveness in critically ill patients
Authors: Lafanechère A , Pène F , Goulenok C , Delahaye A , Mallet V , Choukroun G , Chiche JD , Mira JP , Cariou A 
Published: September 2006

Abstract
Introduction
Esophageal Doppler provides a continuous and non-invasive estimate of descending aortic blood flow (ABF) and corrected left ventricular ejection time (LVETc). Considering passive leg raising (PLR) as a reversible volume expansion (VE), we compared the relative abilities of PLR-induced ABF variations, LVETc and respiratory pulsed pressure variations (ΔPP) to predict fluid responsiveness.

Methods
We studied 22 critically ill patients in acute circulatory failure in the supine position, during PLR, back to the supine position and after two consecutive VEs of 250 ml of saline. Responders were defined by an increase in ABF induced by 500 ml VE of more than 15%.

Results
Ten patients were responders and 12 were non-responders. In responders, the increase in ABF induced by PLR was similar to that induced by a 250 ml VE (16% versus 20%; p = 0.15). A PLR-induced increase in ABF of more than 8% predicted fluid responsiveness with a sensitivity of 90% and a specificity of 83%. Corresponding positive and negative predictive values (PPV and NPV, respectively) were 82% and 91%, respectively. A ΔPP threshold value of 12% predicted fluid responsiveness with a sensitivity of 70% and a specificity of 92%. Corresponding PPV and NPV were 87% and 78%, respectively. A LVETc of 245 ms or less predicted fluid responsiveness with a sensitivity of 70%, and a specificity of 67%. Corresponding PPV and NPV were 60% and 66%, respectively.

Conclusion
The PLR-induced increase in ABF and a ΔPP of more than 12% offer similar predictive values in predicting fluid responsiveness. An isolated basal LVETc value is not a reliable criterion for predicting response to fluid loading.
Locomotion byAbdopus aculeatus(Cephalopoda: Octopodidae):walking the line between primary and secondary defenses
Authors: Huffard Christine L. 
Published: September 2006

SUMMARYSpeeds and variation in body form during crawling, bipedal walking,swimming and jetting by the shallow-water octopus Abdopus aculeatuswere compared to explore possible interactions between defense behaviors and biomechanics of these multi-limbed organisms. General body postures and patterns were more complex and varied during the slow mode of crawling than during fast escape maneuvers such as swimming and jetting. These results may reflect a trade-off between predator deception and speed, or simply a need to reduce drag during jet-propelled locomotion. Octopuses swam faster when dorsoventrally compressed, a form that may generate lift, than when swimming in the head-raised posture. Bipedal locomotion proceeded as fast as swimming and can be considered a form of fast escape (secondary defense) that also incorporates elements of crypsis and polyphenism (primary defenses). Body postures during walking suggested the use of both static and dynamic stability. Absolute speed was not correlated with body mass in any mode. Based on these findings the implications for defense behaviors such as escape from predation, aggression, and `flatfish mimicry' performed by A. aculeatus and other octopuses are discussed.
Centre of mass movement and mechanical energy fluctuation during gallop locomotion in the Thoroughbred racehorse
Authors: Pfau Thilo , Witte Thomas H. , Wilson Alan M. 
Published: September 2006

SUMMARYDuring locomotion cyclical interchange between different forms of mechanical energy enhances economy; however, 100% efficiency cannot be achieved and ultimately some mechanical work must be performed de novo. There is a metabolic cost associated with fluctuations in mechanical energy, even in the most efficient animals. In this study we investigate the exchanges between different forms of mechanical energy involved in high-speed gallop locomotion in Thoroughbred race horses during over-ground locomotion using innovative, mobile data collection techniques. We use hoof-mounted accelerometers to capture foot contact times, a GPS data logger to monitor speed and an inertial sensor mounted over the dorsal spinous processes of the fourth to sixth thoracic vertebrae (the withers) of the horse to capture trunk movement with six degrees of freedom. Trunk movement data were used to estimate the movement of the centre of mass (CoM). Linear(craniocaudal, mediolateral and dorsoventral) and rotational (roll, pitch and heading) kinematic parameters (displacement, velocity and acceleration) were calculated for seven horses at gallop speeds ranging from 7 to 17 m s-1 during their regular training sessions. These were used to estimate external mechanical energy (potential energy and linear kinetic energy of the CoM) as well as selected components of internal energy (angular kinetic energy). Elastic energy storage in the limbs was estimated from duty factor, sine wave assumptions and published leg stiffness values.External mechanical energy changes were dominated by changes in craniocaudal velocity. Potential energy change, which was in phase with craniocaudal energy during the front limb stances, was small. Elastic energy storage in the limbs was small compared to the overall amplitude of fluctuation of external mechanical energy. Galloping at high speeds does not therefore fit classical spring mass mechanics.
The locomotor kinematics of Asian and African elephants: changes with speed and size
Authors: Hutchinson John R. , Schwerda Delf , Famini Daniel J. , Dale Robert H. I. , Fischer Martin S. , Kram Rodger 
Published: September 2006

SUMMARYFor centuries, elephant locomotion has been a contentious and confusing challenge for locomotion scientists to understand, not only because of technical difficulties but also because elephant locomotion is in some ways atypical of more familiar quadrupedal gaits. We analyzed the locomotor kinematics of over 2400 strides from 14 African and 48 Asian elephant individuals (body mass 116-4632 kg) freely moving over ground at a 17-fold range of speeds, from slow walking at 0.40 m s-1 to the fastest reliably recorded speed for elephants, 6.8 m s-1. These data reveal that African and Asian elephants have some subtle differences in how size-independent kinematic parameters change with speed. Although elephants use a lateral sequence footfall pattern, like many other quadrupeds, they maintain this footfall pattern at all speeds, shifting toward a 25% phase offset between limbs (singlefoot) as they increase speed. The duty factors of elephants are greater for the forelimbs than for the hindlimbs, so an aerial phase for the hindquarters is reached at slower speeds than for the forequarters. This aerial phase occurs at a Froude number of around 1,matching theoretical predictions. At faster speeds, stance and swing phase durations approach asymptotes, with the duty factor beginning to level off,concurrent with an increase in limb compliance that likely keeps peak forces relatively low. This increase of limb compliance is reflected by increased compression of the hindlimbs. Like other tetrapods, smaller elephants are relatively more athletic than larger ones, but still move very similarly to adults even at &lt;500 kg. At any particular speed they adopt greater relative stride frequencies and relative stride lengths compared to larger elephants. This extends to near-maximal locomotor performance as well - smaller elephants reach greater Froude numbers and smaller duty factors, hence likely reach relatively greater peak loads on their limbs and produce this force more rapidly. A variety of lines of kinematic evidence support the inference that elephants change their mechanics near a Froude number of 1 (if not at slower speeds), at least to using more compliant limbs, if not spring-like whole-body kinetics. In some ways, elephants move similarly to many other quadrupeds,such as increasing speed mainly by increasing stride frequency (except at fast speeds), and they match scaling predictions for many stride parameters. The main difference from most other animals is that elephants never change their footfall pattern to a gait that uses a whole-body aerial phase. Our large dataset establishes what the normal kinematics of elephant locomotion are, and can also be applied to identify gait abnormalities that may signal musculoskeletal pathologies, a matter of great importance to keepers of captive elephants.
Wing beat kinematics of a nectar-feeding bat,Glossophaga soricina,flying at different flight speeds and Strouhal numbers
Authors: Norberg Ulla M. Lindhe , Winter York 
Published: September 2006

SUMMARYHigh-speed film analysis showed that the wing beat kinematics in Glossophaga soricina change gradually with increasing flight speed,indicating that there is no sudden gait change at any particular, critical,flight speed. The flight of two adult specimens was studied over a range of flight speeds (1.23-7.52 ms-1) in a 30 m long flight tunnel. During the upstroke in hovering and slow flight there is a tip-reversal or supination of the handwings, which thus produce a backward flick. This backward motion successively disappears at speeds V≈3.2 ms-1, above which the wingtip path becomes more vertical or directed upwards-forwards relative to the still air (the stroke plane angle increasing with flight speed as α=44.8V0.29). We found no correlations between either span ratio SR (the ratio of the wing span on the upstroke to that on the downstroke) and V, or downstroke ratio (the duration of the downstroke divided by the total stroke period) and V.On the other hand, SR decreases significantly with increasing wing beat frequency f, SR∝f-0.40. The Strouhal number (St=f×amplitude/V), a dimensionless parameter describing oscillating flow mechanisms and being a predictor of the unsteadiness of the flow, decreases with the speed as St∝V-1.37. Close to the theoretical minimum power speed (4-6 m s-1) G. soricina operates with a Strouhal number in the region 0.17&lt;St&lt;0.22, which is associated with efficient lift and thrust production. At slower speeds, 3.4-4 m s-1, St is 0.25-0.4, which is still within the favourable region. But at speeds below 3 m s-1St becomes higher(0.5&lt;St&lt;0.68), indicating that unsteady effects become important, with unfavourable lift and thrust production as a result. Only at these speeds do the bats perform the backward flick during the upstroke, which may produce thrust. This may serve as a compensation in some bats and birds to increase aerodynamic performance.
Laboratory behavioural assay of insect magnetoreception:magnetosensitivity of Periplaneta americana
Authors: Vácha Martin 
Published: September 2006

SUMMARY
A relatively simple all-laboratory behavioural assay of insect magnetoreception has been developed. We found non-conditioned reactions of American cockroach to the periodical shifts of the geomagnetic field. The movement activity of animals individually placed into Petri dishes was scored as a number of body turns. Test groups were exposed to a 90-min interval with the horizontal component of the geomagnetic field periodically rotated by 60° back and forth with 5 min periodicity. The number of body turns was compared with the preceding and following intervals and with the corresponding interval of the control group kept in the natural field. We obtained a significant increase in activity when changes in field were applied. Interestingly, the period of increased activity did not coincide precisely with the 90 min stimulation interval. The onset of animal restlessness was delayed by tens of minutes and persisted correspondingly after the stimulation stopped. A respective evaluation criterion was suggested and verified.
Owing to its simplicity and minimal manipulation of the insects, together with low demands on the memory and motivation state of animals, the approach potentially may be used as a laboratory diagnostic tool indicating magnetoreception in insect neurophysiology research.
Infrared Spectroscopic Study of Adsorbed Water on Reduced-Charge Na/Li-Montmorillonites
Authors: Sposito Garrison , Prost R. , Gaultier J.-P. 
Published: September 2006

AbstractInfrared (IR) spectra in the fundamental and near-IR regions were obtained for Na-saturated Wyoming montmorillonite and reduced-charge Na/Li-saturated Wyoming montmorillonites hydrated under water vapor at 50% RH and dehydrated under vacuum. For the Na-montmorillonite, changes in the intensities of the structural OH-bending modes, particularly that of the MgAlOH group, were observed as the clay was dehydrated. This result was interpreted as evidence that exchangeable Na ions lose solvation water and settle into the ditrigonal cavities on the clay surface as it becomes desiccated. For the Na/Li-montmorillonites, the structural OH-bending modes also decreased in IR intensity because of Li+ migration into the octahedral sheet. The fundamental IR spectra of D2O adsorbed by the montmorillonites showed characteristic absorptions at 2685, 2510, 2400, and 1205 cm-1 that decreased in intensity proportionally to the cation-exchange capacity. This result, along with corroborating data from X-ray powder diffractograms and from near-IR diffuse reflectance spectra of H2O adsorbed by the clays, suggest that the exchangeable cations on Na-montmorillonite dissociated from the clay surface as it hydrated and played a significant role in organizing the structure of adsorbed water at low water contents.
Infrared Spectra of Thiolane and Tetramethylene Sulfoxide Adsorbed on Montmorillonite
Authors: Lorprayoon V. , Condrate R. A. 
Published: September 2006

AbstractInfrared spectra (4000-1200 cm-1) were obtained for several homoionic montmorillonite films on which tetramethylene sulfoxide (TMSO) or thiolane were adsorbed at various temperatures and for different periods of exposure. The spectra indicate that the Na-, H-, and natural montmorillonite complexes contain a physically adsorbed species, whereas transition metal-montmorillonite complexes contain both physically adsorbed and metal-complexed species in their interlamellar spaces. Apparently, thiolane adsorbed on most montmorillonites undergoes oxidation to TMSO in an air atmosphere. Consistent with the mechanism proposed earlier for aqueous solutions, the rate of sulfoxide formation increases by increasing the pH of the suspensions from which the clay films were deposited or by increasing the concentration of the water molecules in the interlamellar spaces. The infrared spectra of γ-thiolactone adsorbed on Co-montmorillonites suggest that sulfoxide-type molecules are formed which chelate to the Co ions in the interlamellar spaces.
Apparent Charge Heterogeneity in Kaolins in Relation to Their 2:1 Phyllosilicate Content
Authors: Talibudeen Oscar , Goulding Keith W. T. 
Published: September 2006

AbstractMeasurements of the differential heats of K-Ca exchange are used to show that 6 groups of sites (ranging from −13.8 to −5.1 kJ/eq and with as many as 4 in any one sample) exist in kaolins that range from 0 to 15% in their 2:1 phyllosillicate content. These heat values, coupled with entropies of exchange, suggest that 0.1−10% vermiculitic, micaceous, and smectitic layers are present, presumably interstratified with kaolinitic layers which are assumed to have no permanent charge. Changes in the activity coefficients of adsorbed K with K saturation confirm these conclusions qualitatively. Thus, fK values at x ↑ 0 correlate inversely (r2 = 0.655) with the content of vermiculite + partially expanding micas, and x values at maximum fK indicate the content of vermiculite + nonexpanding mica + partially expanding micas (r2 = 0.732).
Thermal Transformation of Antigorite as Studied by Electron-Optical Methods
Authors: Santos Helena de Souza , Yada Keiji 
Published: September 2006

AbstractThe thermal transformation of a Brazilian antigorite heated dry from 600° to 1300°C, was studied by high resolution electron microscopy and selected area electron diffraction (SAD). Below 600°C, the antigorite particles did not change morphologically or crystallographically, as evidence by the presence of the superlattice in the SAD patterns and lattice images. At 650°C, traces of antigorite remained, although the superlattice structure had disappeared and the first indications of forsterite formation were observed in the same SAD. Diffraction patterns of the transition phases showed various topotactical relationships between antigorite and forsterite. At 800°C, the crystallization to forsterite was much more pronounced. At 900°C, the individual particles retained their original shapes, but they were actually pseudomorphs, for their SAD patterns showed only forsterite. Between 1000° and 1300°C various topotactical relationships were observed. Although the overall transformation to forsterite appears to be similar for both chrysotile and antigorite, the transformation of antigorite took place at a slightly higher temperature (~50°C) with a larger number of topotactical relationships than for chrysotile. Enstatite was formed at 1300°C, but it was impossible to determine the topotactic relations between enstatite and forsterite, which was possible with chrysotile.
Noncentric Layer Silicates: An Optical Second Harmonic Generation, Chemical, and X-Ray Study
Authors: Guggenheim Stephen , Schulze Walter A. , Harris Gene A. , Lin Jiunn-Chorng 
Published: September 2006

AbstractTwenty-nine chlorites, seventeen lithium-free micas, and twenty-two lithium-bearing micas from diverse localities have been studied by X-ray diffraction, microprobe, and optical second harmonic generation (SHG) techniques to determine which are noncentric and the cause of acentricity. Manandonite (B-rich chlorite) and cookeite, both crystallizing in the Ia form, are acentric. Sudoite-IIb gave a questionable SHG signal, possibly indicating acentricity. All other chlorites gave null signals. Bityite, a Li, Be mica similar to margarite, was determined from the positive SHG response to be acentric. It crystallizes in the 2M1 form and, by analogy to margarite, is ordered tetrahedrally in subgroup symmetry, Cc. Masutomilite-1M and “cryophyllite“-1M (a zinnwaldite high in Al and Si, but low in Fe) are acentric and most probably crystallize in space group C2, thus allowing a noncentric octahedral ordering pattern. Lepidolites showed a diversity in SHG response with only a few being acentric; a lepidolite-1M from Mesagrande, California, a lepidolite-3T from Windhuk, South West Africa, and a lepidolite-2M2 from Nagatare, Japan, gave positive SHG responses. The Japanese material is complexly intergrown and twinned, and intergrain reflection or refraction may have produced spurious signals.Most lithium-free micas showed diversity in SHG response and, although most were non-emitters, clintonite from Amity, New York, showed a positive response, but this sample is twinned and shows stacking disorder. A “manganophyllite”-1M (manganoan phlogopite) from Langban, Sweden, showed a very weak positive response; however, the presence of Mn alone is not suffcient to produce octahedral cation ordering in noncentric subgroup symmetry. Two manganoan phlogopites from Japan were refined in subgroup symmetry, and the higher order and ideal symmetry of C2/m was confirmed.
Surface Properties of Smectites Exchanged with Mono- and Biprotonated 1,4-Diazobicyclo(2,2,2)-Octane
Authors: Van Leemput L. , Stul M. S. , Maes A. , Uytterhoeven J. B. , Cremers A. 
Published: September 2006

AbstractSmectites exchanged to various degrees with mono- or biprotonated 1,4-diazobicyclo(2,2,2)-octane (Dabco) have a porous structure in which the organic molecule acts as a “pillar.” Less Dabco2+ than Dabco1+ was necessary both to initiate and to complete expansion, whereas for both Dabco1+ and Dabco2+ the threshold for expansion increased with the charge density of the clay. Interstratification of 9.7-Å and 14.5-Å (Dabco1+) or 14.1-Å (Dabco2+) layers was observed before full expansion occurred.Nitrogen sorption isotherms on partially exchanged Dabco1+- and Dabco2+-clays are of the BET II and Langmuir type respectively, whereas n-butane adsorbed according to BET type II for both cationic forms. The specific surface area was governed by the number of Dabcoz+ pillars, irrespective of the inorganic cation, and increased with Dabcoz+ content even beyond the composition where full expansion was reached and notwithstanding the increasing number of silicate layers in the c direction of the crystal units. This relationship is explained by an enhanced random interleaving of clay platelets in the stacking units containing Dabcoz+.
Effect of pH on the Formation of Goethite and Hematite from Ferrihydrite
Authors: Schwertmann U. , Murad E. 
Published: September 2006

AbstractStorage of ferrihydrite in aqueous suspensions at 24°C and pHs between 2.5 and 12 for as long as three years resulted in the formation of goethite and hematite. The proportions and crystallinity of these products varied widely with the pH. Maximum hematite was formed between pH 7 and 8, and maximum goethite at pH 4 and at pH 12. The crystallinity of both products, as indicated by X-ray powder diffraction line broadening and magnetic hyperfine field values and distribution widths, was poorer, the lower the proportion of the corresponding product in the mixture. The existence of two competitive formation processes is suggested: goethite is formed via solution, preferably from monovalent Fe(III) ions [Fe(OH)2+ and Fe(OH)4−], and hematite by internal rearrangement and dehydration within the ferrihydrite aggregates. This concept relates the proportions of goethite and hematite to the activity of the Fe(III) ion species in solution, and implies that conditions favorable for the formation of goethite are unfavorable for that of hematite and vice versa.