bluuebunny/crossref_metadata_2025 huggingface dataset:
THE EFFECTS OF CALCIUM CONCENTRATION ON THE INHIBITION OF CHOLINERGIC NEUROTRANSMISSION IN THE MYENTERIC PLEXUS OF GUINEA‐PIG ILEUM BY ADENINE NUCLEOTIDES
Authors: DOWDLE E.B. , MASKE R.
Published: May 2015

Adenosine and the adenine nucleotides AMP, ADP, ATP, cyclic AMP, NAD, NADP and NADH produced a dose‐related inhibition of the contractile response of guinea‐pig ileum longitudinal muscle‐myenteric plexus strips to low frequencies (< 1 Hz) of electrical field stimulation.

These compounds inhibited hexamethonium‐sensitive contractions induced by nicotine but did not alter the responses to exogenous acetylcholine, and the acetylcholine output from the myenteric plexus was inhibited by the adenyl compounds. These findings indicate that adenine derivatives act at a presynaptic site on postganglionic cholinergic neurones.

The degree of inhibition produced by adenine compounds was inversely related to the calcium concentration of the bath fluid over a range of calcium concentrations (1 to 5 mm) that had no effect on the responses of the muscle to exogenous acetylcholine.

The inhibition produced by adenine derivatives was antagonized by theophylline and augmented by dipyridamole. Both of these interactions were sensitive to, and synergistic with, alterations of the concentration of calcium in the bath fluid.

The results suggest that adenine compounds inhibit acetylcholine release from the myenteric plexus by diminishing the availability of intracellular calcium ions required for neurotransmitter release.
UPTAKE OF RADIOCALCIUM BY NERVE ENDINGS ISOLATED FROM RAT BRAIN: KINETIC STUDIES
Authors: GRIPENBERG J. , HEINONEN E. , JANSSON S.‐E. , Heinonen E. , Tolppanen E. M.
Published: May 2015

The uptake of radiocalcium by nerve‐ending particles isolated from rat brain was studied in vitro by means of a rapid lanthanum quenching technique.

The observed uptake fits a theoretical three‐compartment model with two separate uptake phases, a fast, initial phase followed by a late, slow phase. This holds true during control conditions as well as during high‐potassium stimulation.

The uptake as a function of the external calcium concentration can be described in terms of Michaelis‐Menten kinetics during high‐potassium stimulation. Under control conditions the fit is clearly applicable but statistically not as good as during potassium stimulation.

The affinity for the uptake of calcium remains unchanged under control conditions while during high‐potassium stimulation the affinity drastically decreases during the late, slow phase of uptake.

During high‐potassium stimulation the maximal velocity of calcium uptake is twice that during control conditions. This holds true for both the fast and the slow phases of the uptake.

Mg2+ has an inhibitory effect on the uptake, the inhibition being more effective during high‐potassium stimulation. Tetrodotoxin has a slight inhibitory effect additional to that exerted by Mg2+ during the initial phase of uptake into high potassium stimulated synaptosomes.
DO MOTOR‐NERVE TERMINALS HAVE γ‐AMINOBUTYRIC ACID RECEPTORS?
Authors: SMART T.G.
Published: May 2015

γ‐Aminobutyric acid (GABA, 0.1 to 1 mm) had no significant effect on the amplitude, rise time, half decay time or frequency of miniature endplate potentials (m.e.p.ps) at the frog or mouse neuromuscular junctions in vitro.

Addition of GABA (1 mm) to preparations previously treated with 11 mm K+‐Ringer did not cause any further increase in m.e.p.p. frequency. GABA also failed to increase the m.e.p.p. frequency in a low Cl−‐Ringer.

GABA (0.1 to 1 mm) did not reduce the high m.e.p.p. frequency induced by veratrine (20 to 40 mg/l).

GABA (0.5 to 1 mm) did not affect the amplitude of the extracellularly‐recorded nerve terminal spike, whereas 15 mm [K+] reduced the spike.

The quantal content (m) of the evoked endplate potential was not significantly altered by GABA; 9 mm [K+] significantly increased m.

When external d.c. potential differences were recorded in a three‐chambered bath, GABA (0.1 to 1 mm) produced a very small depolarization if applied to the phrenic nerve trunk, but not if applied to the pre‐terminal axon/motor nerve terminal region. Carbachol (0.3 to 1 mm) evoked a small depolarization when applied to the nerve terminal chamber.

These results fail to provide evidence for the existence of GABA receptors on motor nerve terminals.
EFFECT OF TILTING ON THE PRESSOR RESPONSES TO McN‐A‐343, A MUSCARINIC SYMPATHETIC GANGLION STIMULANT
Authors: FIELDEN R. , SUTTON T.J. , TAYLOR E.M.
Published: May 2015

In anaesthetized cats and dogs treated with mecamylamine, the pressor response to McN‐A‐343 was increased when the animals were changed from a supine to a head‐up, tilted position. This potentiation was not seen in rats.

The potentiation of the McN‐A‐343 pressor response was not affected by propranolol, destruction of the brain, or removal of the intestines, spleen or adrenal glands. It was promptly abolished by applying pressure to the lower half of the tilted animal. No increase in the pressor response to McN‐A‐343 occurred when cats were tilted head down. The potentiated response in tilted cats was abolished by atropine.

The pressor effects of adrenaline, noradrenaline, tryamine and angiotensin in cats treated with mecamylamine were either reduced or unchanged when the animal was changed from the supine to the tilted position. In one cat not treated with mecamylamine in which orthostatic hypotension occurred, tilting potentiated the pressor responses to dimethyl phenylpiperazinium iodide.

In cats anaesthetized with chloralose, the reflex pressor response to bilateral carotid occlusion was reduced by tilting. After mecamylamine treatment the residual atropine‐sensitive response to carotid occlusion was potentiated when the animal was placed in the tilted position.

These results suggest that muscarinic stimulation of sympathetic ganglia by McN‐A‐343 raises blood pressure by predominantly reducing venous capacity, in contrast to noradrenaline and angiotension which increase blood pressure mainly by arterial vasoconstriction.

It is not clear whether this is a general property of sympathetic ganglionic stimulation or is restricted to stimulation of muscarinic sites.
A STUDY OF THE ROLE OF CYCLIC ADENOSINE 3′,5′‐MONOPHOSPHATE IN THE DEPRESSION BY OPIATES AND OPIOID PEPTIDES OF EXCITATORY JUNCTION POTENTIALS IN THE MOUSE VAS DEFERENS
Authors: NORTH R.A. , VITEK L.V.
Published: May 2015

Excitatory junction potentials (e.j.ps) were recorded with intracellular microelectrodes from smooth muscle cells of the mouse isolated vas deferens. The amplitude of the e.j.p. was used as a measure of transmitter release evoked by applying single pulse stimuli to the intramural nerves.

Cyclic adenosine 3′,5′‐monophosphate (cyclic AMP) and dibutyryl cyclic AMP (db cyclic AMP, up to 1 mm) depressed the amplitude of e.j.ps, probably by interacting with extracellular sites on the nerve terminals, similar to those responsive to adenosine.

The phosphodiesterase inhibitors, 1‐methyl‐3‐isobutyl xanthine (IBMX) and 1‐ethyl‐4‐hydrazino‐1H‐pyrazolo(3,4‐b)pyridine‐5‐carboxylic acid, ethylester, hydrochloride (SQ20,006) increased e.j.p. amplitude; this increase was much greater when the phosphodiesterase inhibitor was applied together with db cyclic AMP.

Neither the cyclic nucleotides nor the phosphodiesterase inhibitors altered the resting membrane potential of smooth muscle cells.

The amplitude of the e.j.p. was depressed by normorphine, d‐Ala2‐Met5‐enkephalinamide (DAEA) and d‐Ala2‐d‐Leu5‐enkephalin (DADL) with respective EC50s of 560 nm, 49 nm and 510 pm.

There was no change in the EC50 for normorphine in the presence of cyclic AMP (1 mm) or in the presence of a combination of IBMX (50 μm) and db cyclic AMP (500 μm). Similarly, the depression of the e.j.p. by DAEA or DADL was not affected by the combination IBMX (500 μm) and db cyclic AMP (250 μm).

These findings provide evidence against the hypothesis that a reduction in cyclic AMP levels in nerve terminals is an essential step in the inhibition by opiates and opioid peptides of transmitter release.
Ant tending impairs performance of Aenasius bambawalei by manipulating the honeydew composition produced by Phenacoccus solenopsis
Authors: Zhou A. M. , Kuang B. Q. , Gao Y. R. , Wang M.‐Q.
Published: May 2015

Honeydew produced by hemipterans is known as a possible kairomonal resource for parasitoids. The application of artificial honeydew effectively improves the performance of natural enemies. Aenasius bambawalei is a particularly dominant and aggressive endoparasitoid of the invasive mealybug Phenacoccus solenopsis. Our previous study showed that tending by the ghost ant Tapinoma melanocephalum significantly reduced the parasitism of A. bambawalei. We hypothesize that ghost ant tending influences host location of parasitoids by manipulating the composition of the honeydew produced by mealybugs. In this study, we tested whether the honeydew composition differs between treatments with and without ant attendance and whether changes in the honeydew influence the performance of A. bambawalei. Our results show that the sucrose concentration increased significantly in the ant‐attendance treatment but decreased when ant attendance was switched to an ant‐exclusion treatment; the inverse was true for the glucose concentration. Compared with the plastic honeydew treatment (mealybug with ant attendance), parasitoids spent much more time searching, had longer lifespans and showed higher parasitism on filter papers treated with natural honeydew (mealybug without any pre‐treatment) and those treated with convalescent honeydew (mealybug having experienced ant attendance and then switched to ant exclusion). These results support the hypothesis that ant tending influences the performance of parasitoids by manipulating honeydew composition.
Effect of Preoperative Occlusal Matrices on the Vickers Microhardness of Composite Disks Polymerized with QTH and LED Lamps
Authors: Castillo‐Oyagüe Raquel , Milward Paul J. , Martín‐Cerrato Alicia , Lynch Christopher D.
Published: May 2015

Purpose

This study aimed to assess the reliability of the preoperative occlusal matrix technique in terms of the surface Vickers microhardness (VMH) of the underlying composite restorative material.

Materials and Methods

Two hundred microhybrid composite cylinders were built up and light‐cured in a single‐layer step, forming two experimental groups (N = 100) according to their heights (1.5 mm/2 mm). Each group was divided into five subgroups (N = 20) depending on the matrix thickness (no matrix/0.5 mm/1 mm/2 mm/3 mm). Half the specimens per subgroup (N = 10) were randomly polymerized with a quartz‐tungsten‐halogen (QTH) light‐curing unit (LCU). The remaining half were cured using a light‐emitting diode lamp. The top and bottom samples' sides were tested for VMH at 1 hour and 24 hours post‐curing using a universal VMH machine. A multiple analysis of variance with repeated measurements for the “surface” factor and the Student–Newman–Keuls test were run (α = 0.05). Bottom/top microhardness ratios were compared with the empirically accepted limit (0.8). Surface topography was analyzed under a scanning electron microscope.

Results

The thinnest matrices provided the significantly best VMH values. LCU, disc height, and time also contributed to VMH. At 24 hours, 2‐mm high discs polymerized with QTH resulted in inadequate microhardness ratios when 1‐mm thick to 3‐mm thick matrices were used.

Conclusion

The thinnest matrices are the most recommendable ones.

Clinical Significance

The esthetics and occlusal reproducibility achieved with customized occlusal matrices fabricated before cavity preparation have been widely demonstrated. However, their effect on the physical properties of the restorations deserves further investigation. Although more studies are necessary, the thinnest matrices seem to be the most suitable to preserve the composite surface VMH and the curing depth.
Full Mouth Implant Rehabilitation with Staged Approach: 6‐Year Clinical Follow‐Up
Authors: Papaspyridakos Panos
Published: May 2015

Objective

The transition of patients from failing dentition to complete arch implant rehabilitation often requires that the patient is rendered edentulous and has to wear a removable complete denture for varying periods of time. In order to avoid removable provisionalization, the staged treatment approach allows for fixed interim prosthesis throughout the rehabilitation process, patient comfort, and prosthodontic control.

Clinical considerations

The purpose of this clinical report is to describe a combination of staged approach with guided flapless surgery for minimally invasive treatment. The patient had fixed interim prostheses during the entire rehabilitation process. The various implant prosthodontic stages are illustrated for the complete arch prosthetic rehabilitation and the 6‐year follow‐up outcome is reported. A patient with debilitated dentition was treated with this combined protocol and was followed for 6 years after definitive prosthesis insertion.

Conclusion

Implant and prosthesis success rates were 100% with minor biologic and no technical complications encountered up to 6‐year recall. Guided surgery has the advantage of prosthetically driven implant placement and minimal postoperative sequelae, whereas the staged approach allows for fixed provisionalization throughout the entire treatment period.

Clinical Significance

As the computer‐guided surgery protocols continue to evolve and improve, further clinical studies are necessary to assess accuracy and make this exciting technology even safer for the average clinician. The clinical significance of this case report lies in the treatment sequence combined with cutting edge technology for maximum patient comfort and prosthodontic control. Guided flapless surgery with prosthodontically driven implant placement led to predictable rehabilitation with no major complications after 6 years. A staged approach with fixed interim prostheses was used throughout the entire rehabilitation period, optimizing patient satisfaction and comfort. Natural canine guidance was the occlusal scheme of choice.
Protracted garnet growth in high‐Peclogite: constraints from multiple geochronology andP–Tpseudosection
Authors: Cheng H. , Cao D.
Published: May 2015

Understanding convergent margin processes requires determination of the onset and the termination of subduction, the duration of subduction‐zone metamorphism, and the subduction zone polarity. Garnet growth and intracrystalline zonation can be used to constrain the timing, duration and kinetics of tectonometamorphic processes. An eclogite from the Huwan shear zone in the Hong'an orogen was investigated with combined pseudosection analysis and multiple geochronologies. The pseudosection analysis illustrates that garnet growth is continuous and along an early near‐isothermal trajectory followed by a near‐isobaric heating path from 1.9 GPa/500 °C to 2.4 GPa/575 °C and subsequent near‐isothermal decompression.40Ar/39Ar dating of an amphibole inclusion in garnet from the eclogite yielded an age of 310 ± 5 Ma, which is consistent with a U–Pb age of 305 ± 3 Ma for the metamorphic zircon within uncertainty. Garnet core and rim material produced Lu–Hf ages of 296.9 ± 3.8 and 256.9 ± 3.9 Ma respectively; the latter is consistent with its Sm–Nd age of 254.3 ± 4.6 Ma for the same aliquots. Similarly, limited zircon U–Pb ages ofc. 257 Ma were obtained in zircon rims with garnet inclusions. These ages were interpreted to bracket the period of garnet growth and the difference of up toc. 40 Ma is best explained by protracted garnet growth. We propose that the rocks represent detachment of part of the downgoing slab and remained free of significant compression/decompression or heating/cooling close to the subduction channel, most likely underplating the mantle wedge, for a long time. These rocks were incorporated into the following subduction channel due to the successive entry of the buoyant materials, and exhumed at some time later thanc. 254 Ma. The increasing observations of protracted garnet growth and long‐lived subduction in various orogens worldwide demand more sophisticated geodynamic models.
Light‐dependent gene activation in Aspergillus nidulans is strictly dependent on phytochrome and involves the interplay of phytochrome and white collar‐regulated histone H3 acetylation
Authors: Hedtke Maren , Rauscher Stefan , Röhrig Julian , Rodríguez‐Romero Julio , Yu Zhenzhong , Fischer Reinhard
Published: May 2015

The ability for light sensing is found from bacteria to humans but relies only on a small number of evolutionarily conserved photoreceptors. A large number of fungi react to light, mostly to blue light. Aspergillus nidulans also responds to red light using a phytochrome light sensor, FphA, for the control of hundreds of light‐regulated genes. Here, we show that photoinduction of one light‐induced gene, ccgA, occurs mainly through red light. Induction strictly depends on phytochrome and its histidine‐kinase activity. Full light activation also depends on the Velvet protein, VeA. This putative transcription factor binds to the ccgA promoter in an fphA‐dependent manner but independent of light. In addition, the blue light receptor LreA binds to the ccgA promoter in the dark but is released after blue or red light illumination and together with FphA modulates gene expression through histone H3 modification. LreA interacts with the acetyltransferase GcnE and with the histone deacetylase HdaA. ccgA induction is correlated to an increase of the acetylation level of lysine 9 in histone H3. Our results suggest regulation of red light‐induced genes at the transcriptional level involving transcription factor(s) and epigenetic control through modulation of the acetylation level of histone H3.
Satisficing and Motivated Submaximization (in the Philosophy of Religion)
Authors: Tucker Chris
Published: May 2015

In replying to certain objections to the existence of God, Robert Adams, Bruce Langtry, and Peter van Inwagen assume that God can appropriately choose a suboptimal world, a world less good than some other world God could have chosen. A number of philosophers, such as Michael Slote and Klaas Kraay, claim that these theistic replies are therefore committed to the claim that satisficing can be appropriate. Kraay argues that this commitment is a significant liability. I argue, however, that the relevant defenses of theism are committed to the appropriateness of, not satisficing, but motivated submaximization. When one submaximizes with motivation, one aims at the optimum but accepts the good enough because of a countervailing consideration. When one satisfices, one aims at the good enough and chooses the good enough because it realizes her aim at the good enough. While commitment to the appropriateness of satisficing may be a significant liability, commitment to the appropriateness of motivated submaximization is not.
When blood transfusion medicine becomes complicated due to interference by monoclonal antibody therapy
Authors: Oostendorp Marlies , Lammerts van Bueren Jeroen J. , Doshi Parul , Khan Imran , Ahmadi Tahamtan , Parren Paul W.H.I. , van Solinge Wouter W. , De Vooght Karen M.K.
Published: May 2015

BACKGROUND

Monoclonal antibodies (MoAbs) are increasingly integrated in the standard of care. The notion that therapeutic MoAbs can interfere with clinical laboratory tests is an emerging concern that requires immediate recognition and the development of appropriate solutions. Here, we describe that treatment of multiple myeloma patients with daratumumab, a novel anti‐CD38 MoAb, resulted in false‐positive indirect antiglobulin tests (IATs) for all patients for 2 to 6 months after infusion. This precluded the correct identification of irregular blood group antibodies for patients requiring blood transfusion.

STUDY DESIGN AND METHODS

The IAT was performed using three‐ and 11‐donor‐cell panels. Interference of daratumumab and three other anti‐CD38 MoAbs was studied using fresh‐frozen plasma spiked with different MoAb concentrations. Additionally it was tested whether two potentially neutralizing agents, anti‐idiotype antibody and recombinant soluble CD38 (sCD38) extracellular domain, were able to inhibit the interference.

RESULTS

The CD38 MoAbs caused agglutination in the IAT in a dose‐dependent manner. Addition of an excess of anti‐idiotype antibodies or sCD38 protein to the test abrogated CD38 MoAb interference and successfully restored irregular antibody screening and identification.

DISCUSSION

CD38 MoAb therapy causes false‐positive results in the IAT. The reliability of the test could be restored by adding a neutralizing agent against the CD38 MoAb to the patient's plasma. This study emphasizes that during drug development, targeted therapeutics should be investigated for potential interference with laboratory tests. Clinical laboratories should be informed when patients receive MoAb treatments and matched laboratory tests to prevent interference should be employed.
Handling low hemoglobin and iron deficiency in a blood donor population: 2 years' experience
Authors: Magnussen Karin , Ladelund Steen
Published: May 2015

BACKGROUND

Iron deficiency and blood donors with low hemoglobin (Hb) concentration are well‐known challenges in any blood bank setting. In the Capital Region of Denmark, a new approach was adopted that centralized measurement of Hb, initiated ferritin (F) measurement, and established a center for donor Hb and iron. An algorithm was created based on Hb and F levels, which drove decisions on outreach by the donor Hb and iron resource team to the donor, including whether to provide iron supplementation or, on rare occasions, a referral to the donor's general practitioner.

STUDY DESIGN AND METHODS

The change in Hb for repeat donors was followed during the first 2 years of the intervention strategy, which included measurements of F and offering intermittent iron supplementation to some of the donors.

RESULTS

In 2 years, 62,663 blood donors donated 193,288 units of blood and 318 donors gave 754 complete blood count blood samples. Over time in the repeat donors, the Hb increased from 15.39 to 15.60 g/dL and 13.85 to 14.06 g/dL in male and female donors, respectively, and the proportion of donors with low Hb decreased from 0.9% to 0.3% and 3.9% to 2.7% for the male and female donors, respectively.

CONCLUSION

The program with goal‐directed iron supplementation only to those that would benefit has led to an increase in Hb concentration and a reduction in the proportion of donors with low Hb concentration.
Development and Validation of a Three-Dimensional Computational Fluid Dynamics Analysis for Journal Bearings Considering Cavitation and Conjugate Heat Transfer
Authors: Song Yin , Gu Chun-wei
Published: May 2015

Computational fluid dynamics (CFD) analysis, which solves the full three-dimensional (3D) Navier–Stokes equations, has been recognized as having promise in providing a more detailed and accurate analysis for oil-film journal bearings than the traditional Reynolds analysis, although there are still challenging issues requiring further investigation, such as the modeling of cavitation and the modeling of conjugate heat transfer effects in the CFD analysis of bearings. In this paper, a 3D CFD method for the analysis of journal bearings considering the above two effects has been developed; it employs three different cavitation models, including the Half-Sommerfeld model, a vaporous cavitation model, and a gaseous cavitation model. The method has been used to analyze a two-groove journal bearing and the results are validated with experimental measurements and the traditional Reynolds solutions. It is found that the CFD method which considers the conjugate heat transfer and employs the gaseous cavitation model gives better predictions of both bearing load and temperature than either the traditional Reynolds solution or CFD with other cavitation models. The CFD results also show strong recirculation of the fresh oil in the grooves, which has been neglected in the traditional Reynolds solution. The above results show conclusively that the present 3D CFD method considering the conjugate heat transfer and employing the gaseous cavitation model provides an efficient tool for more detailed and accurate analysis for bearing performance.
Heat and Mass Transfer in Planar Anode-Supported Solid Oxide Fuel Cells: Effects of Interconnect Fuel/Oxidant Channel Flow Cross Section
Authors: Manglik Raj M. , Magar Yogesh N.
Published: May 2015

Heat and mass transfer in a planar anode-supported solid oxide fuel cell (SOFC) module, with bipolar-plate interconnect flow channels of different shapes are computationally simulated. The electrochemistry is modeled by uniform supply of volatile species (moist hydrogen) and oxidant (air) to the electrolyte surface with constant reaction rate via interconnect channels of rectangular, trapezoidal, and triangular cross sections. The governing three-dimensional equations for fluid mass, momentum, energy, and species transport, along with those for electrochemical kinetics, where the homogeneous porous-layer flow is in thermal equilibrium with the solid matrix, are coupled with the electrochemical reaction rate to properly account for the heat and mass transfer across flow-ducts and electrode-interfaces. The results highlight effects of interconnect duct shapes on lateral temperature and species distributions as well as the attendant frictional losses and heat transfer coefficients. It is seen that a relatively shallow rectangular duct offers better heat and mass transfer performance to affect improved thermal management of a planar SOFC.
Computational Modeling of a Solar Thermoelectric Generator
Authors: Ofoegbu Chukwunyere , Mazumder Sandip
Published: May 2015

Solar thermoelectric generators (STEGs) convert solar energy to electricity. The solar energy is first used to heat an absorber plate that serves as the high temperature reservoir. Power is generated by connecting the hot reservoir and cold (ambient) reservoirs with a pair of p- and n-doped thermoelectric legs. Experimental studies have shown that the efficiency of a STEG can reach values of about 5% if the entire setup is placed in near-vacuum conditions. However, under atmospheric conditions, the efficiency decreases by more than an order of magnitude, presumably due to heat loss from the absorber plate by natural convection. A coupled fluid–thermal–electric three-dimensional computational model of a STEG is developed with the objective of understanding the various loss mechanisms that contribute to its poor efficiency. The governing equations of mass, momentum, energy, and electric current, with the inclusion of thermoelectric effects, are solved on a mesh with 60,900 cells, and the power generated by the device is predicted. The computational model predicts a temperature difference (ΔT) of 16.5 K, as opposed to the experimentally measured value of 15 K. This corresponds to a peak power of 0.031 W as opposed to the experimentally measured peak power of 0.021 W. When only radiative losses are considered (i.e., perfect vacuum), the ΔT increases drastically to 131.1 K, resulting in peak power of 1.43 W. The predicted peak efficiency of the device was found to be 0.088% as opposed to the measured value of 0.058%.
The Effect of Physical Exercise on Postural Stability in Sighted Individuals and Those Who Are Visually Impaired: An Analysis Adjusted for Physical Activity and Body Mass Index
Authors: Sadowska Dorota , Stemplewski Rafał , Szeklicki Robert
Published: May 2015

The aim of this study was to assess the effect of physical exercise on postural stability in sighted participants and individuals who are visually impaired, adjusted for potential modulatory effects of physical activity level and body mass index (BMI). The study included 23 participants who were severely visually impaired and 23 sighted participants. Postural stability measurements were taken with open eyes (session I) and with closed eyes (session II). During each session, the mean velocity of the center of pressure (COP) displacements was determined using a force plate both before and after physical exercise. During testing with open eyes, the 2 groups did not differ significantly in terms of their postural response to physical exercise. When examined with closed eyes, the individuals who were visually impaired showed markedly greater postexercise increase in mean velocity of the COP displacement in the mediolateral direction. This intergroup difference was likely a consequence of significantly higher preexercise values of posturographic parameters observed in the sighted participants. More pronounced postexercise changes in the postural stability of sighted participants were associated with lower levels of physical activity and higher values of BMI. Further research is needed to explain the character of the abovementioned relationships in individuals who are visually impaired.
An Examination of Change in Control of the Right and the Left Hand Across the Lifespan
Authors: Flink Tania S. , Iorio Alexandra N.
Published: May 2015

This study examined changes in manual asymmetry across the lifespan using the Purdue pegboard protocol. One hundred and four right-handed individuals were recruited and separated by age decade. Individuals placed pegs into holes as fast as possible in 30 s using the right hand, left hand, and both hands simultaneously. Movements with the right hand were significantly faster than the left hand and for both hands for all age groups. The number of pegs successfully inserted into the holes significantly declined in the sixth decade, and this result was observed for both the right and left hands. No significant differences between the decades were observed with respect to the computed laterality quotient; thus, declines in manual asymmetry with age were not observed. It is suggested that the performance speed declines with age are likely to be due to central factors. Better performance of the right versus left hand across the lifespan supports the right hemi-aging model, and may also be due to practice, the differential roles of the right versus the left hand, and the task itself.
Longitudinal Development of Speech Motor Control: Motor and Linguistic Factors
Authors: Iuzzini-Seigel Jenya , Hogan Tiffany P. , Rong Panying , Green Jordan R.
Published: May 2015

Lip shape in adult talkers is primarily driven by vertical opening; however, little is known about how children converge on this highly organized and efficient lip shape pattern. This longitudinal study investigated the development of lip shape control and its relation to speech and vocabulary acquisition in 28 typically developing children between 3 months and 5 years of age. Results suggested that during infancy lip shape was characterized by horizontal spreading of the lips, but that the contribution of vertical opening increased nonmonotonically over time. This change co-occurred with gains in expressive communication. These data suggest that lip shape may represent an important marker of normal oromotor development. Future work is required to determine the functional significance of the observed changes in lip shape control for identifying children at risk for speech and language impairments.
Information diffusion in structured online social networks
Authors: Li Pei , Zhang Yini , Qiao Fengcai , Wang Hui
Published: May 2015

Nowadays, due to the word-of-mouth effect, online social networks have been considered to be efficient approaches to conduct viral marketing, which makes it of great importance to understand the diffusion dynamics in online social networks. However, most research on diffusion dynamics in epidemiology and existing social networks cannot be applied directly to characterize online social networks. In this paper, we propose models to characterize the information diffusion in structured online social networks with push-based forwarding mechanism. We introduce the term user influence to characterize the average number of times that messages are browsed which is incurred by a given type user generating a message, and study the diffusion threshold, above which the user influence of generating a message will approach infinity. We conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of use in understanding the diffusion dynamics in online social networks and also critical for advertisers in viral marketing who want to estimate the user influence before posting an advertisement.
Antisymmetric Post-Buckling Localization of an Infinite Column on a Nonlinear Foundation with Softening
Authors: Yang Guotao , Bradford Mark A.
Published: May 2015

Field observations reveal that very long members such as railway tracks and pipelines which are subjected to axial compression, induced usually by temperature and/or pressure increases, experience localized buckling. This paper presents a solution for the antisymmetric post-buckling of such members when restrained by a nonlinear foundation that includes softening effects. The principle of minimum total potential is invoked in order to develop the governing differential equations of buckling, as well as the non-linear equations of equilibrium in the post-buckled range of structural response. In order to solve these equations, a semi-analytical solution is proposed based on a perturbation technique, as well as a numerical technique based on a single shooting procedure for the solution of boundary value problems. The results of the analysis show that the post-buckling configuration of the column changes from a lengthwise periodic mode at the initial stages of loading to an isolated sinusoidal mode at the later stages of post-buckling, which represents a localization in the post-buckling range. This response is typical of that observed often in practice. Comparisons between the results of the perturbation technique and those of the numerical approach indicate that the semi-analytical perturbation solution predicts the initial post-buckling response of a column on a nonlinear foundation quite accurately.
AVOIDING EXTINCTION BY MIGRATION: THE CASE OF THE HEAD LOUSE
Authors: CABRERA OCTAVIO , ZANETTE DAMIÁN H.
Published: May 2015

The possibility of spreading by migration, colonizing new spatial domains suitable for development and reproduction, can substantially relieve a biological population from the risk of extinction. By means of a realistic computational model based on empirical data, we study this phenomenon for the human head louse, Pediculus humanus capitis. In particular, we show that a lice colony infesting a single isolated host is prone to extinction by stochastic population fluctuations within an interval of several months, while migration over a relatively small group of hosts in contact with each other is enough to insure the prevalence of the infestation for indefinitely long periods. We characterize the interplay of the size of the host group with the host-to-host contagion probability, which controls a transition between extinction of the lice population and a situation where the infestation is endemic.
Fidelity, sub-fidelity, super-fidelity and their preservers
Authors: Wang Li , Hou Jinchuan , He Kan
Published: May 2015

Sub- and super-fidelity describe respectively the lower and super bound of fidelity of quantum states. In this paper, we obtain several properties of sub- and super-fidelity for both finite- and infinite-dimensional quantum systems. Furthermore, let H be a separable complex Hilbert space and ϕ : 𝒮(H) → 𝒮(H) a map, where 𝒮(H) denotes the convex set of all states on H. We show that, if dim H < ∞, or, if dim H = ∞ and ϕ is surjective, then the following statements are equivalent: (1) ϕ preserves the super-fidelity; (2) ϕ preserves the fidelity; (3) ϕ preserves the sub-fidelity; (4) there exists a unitary or an anti-unitary operator U on H such that ϕ(ρ) = UρU† for all ρ ∈ 𝒮(H).
Thermal Error Modelling of the Spindle Using Data Transformation and Adaptive Neurofuzzy Inference System
Authors: Li Yanlei , Hu Youmin , Wu Bo , Fan Jikai
Published: May 2015

This paper proposes a new method for predicting spindle deformation based on temperature data. The method introduces the adaptive neurofuzzy inference system (ANFIS), which is a neurofuzzy modeling approach that integrates the kernel and geometrical transformations. By utilizing data transformation, the number of ANFIS rules can be effectively reduced and the predictive model structure can be simplified. To build the predictive model, we first map the original temperature data to a feature space with Gaussian kernels. We then process the mapped data with the geometrical transformation and make the data gather in the square region. Finally, the transformed data are used as input to train the ANFIS. A verification experiment is conducted to evaluate the performance of the proposed method. Six Pt100 thermal resistances are used to monitor the spindle temperature, and a laser displacement sensor is used to detect the spindle deformation. Experimental results show that the proposed method can precisely predict the spindle deformation and greatly improve the thermal performance of the spindle. Compared with back propagation (BP) networks, the proposed method is more suitable for complex working conditions in practical applications.
Microstructure, Mechanical, and Biological Properties of Porous Poly(vinylidene fluoride) Scaffolds Fabricated by Selective Laser Sintering
Authors: Huang Wei , Feng Pei , Gao Chengde , Shuai Xiong , Xiao Tao , Shuai Cijun , Peng Shuping
Published: May 2015

Porous poly(vinylidene fluoride) (PVDF) scaffolds were prepared by selective laser sintering. The effects of laser energy density, ranging from 0.66 to 2.16 J/mm2, on microstructure and mechanical properties were investigated. At low energy density levels, PVDF particles could fuse well and the structure becomes dense with the increase of the energy density. Smoke and defects (such as holes) were observed when the energy density increased above 1.56 J/mm2which indicated decomposition of the PVDF powder. The scaffolds appeared to be light yellow and there was a reduction in tensile strength. The fabricated scaffolds were immersed into simulated body fluid for different time to evaluate biostability. In addition, MG63 cells were seeded and cultured for different days on the scaffolds. The testing results showed that the cells grew and spread well, indicating that PVDF scaffolds had good biocompatibility.
Identification of Glioblastoma Phosphotyrosine-Containing Proteins with Two-Dimensional Western Blotting and Tandem Mass Spectrometry
Authors: Guo Tianyao , Wang Xiaowei , Li Maoyu , Yang Haiyan , Li Ling , Peng Fang , Zhan Xianquan
Published: May 2015

To investigate the presence of, and the potential biological roles of, protein tyrosine phosphorylation in the glioblastoma pathogenesis, two-dimensional gel electrophoresis- (2DGE-) based Western blotting coupled with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis was used to detect and identify the phosphotyrosine immunoreaction-positive proteins in a glioblastoma tissue. MS/MS and Mascot analyses were used to determine the phosphotyrosine sites of each phosphopeptide. Protein domain and motif analysis and systems pathway analysis were used to determine the protein domains/motifs that contained phosphotyrosine residue and signal pathway networks to clarify the potential biological functions of protein tyrosine phosphorylation. A total of 24 phosphotyrosine-containing proteins were identified. Each phosphotyrosine-containing protein contained at least one tyrosine kinase phosphorylation motif and a certain structural and functional domains. Those phosphotyrosine-containing proteins were involved in the multiple signal pathway systems such as oxidative stress, stress response, and cell migration. Those data show 2DGE-based Western blotting, MS/MS, and bioinformatics are a set of effective approaches to detect and identify glioblastoma tyrosine-phosphorylated proteome and to effectively rationalize the biological roles of tyrosine phosphorylation in the glioblastoma biological systems. It provides novel insights regarding tyrosine phosphorylation and its potential role in the molecular mechanism of a glioblastoma.
The Role of Intestinal Microbiota in Acute Graft-versus-Host Disease
Authors: Chen Yuanyuan , Zhao Ye , Cheng Qiao , Wu Depei , Liu Haiyan
Published: May 2015

The mammalian intestinal microbiota is a complex ecosystem that plays an important role in host immune responses. Recent studies have demonstrated that alterations in intestinal microbiota composition are linked to multiple inflammatory diseases in humans, including acute graft-versus-host disease (aGVHD). aGVHD is one of the major obstacles in allogeneic hematopoietic stem cell transplantation (allo-HSCT), characterized by tissue damage in the gastrointestinal (GI) tract, liver, lung, and skin. Here, we review the current understanding of the role of intestinal microbiota in the control of immune responses during aGVHD. Additionally, the possibility of using probiotic strains for potential treatment or prevention of aGVHD will be discussed.
Recent Development of Dual-Dictionary Learning Approach in Medical Image Analysis and Reconstruction
Authors: Wang Bigong , Li Liang
Published: May 2015

As an implementation of compressive sensing (CS), dual-dictionary learning (DDL) method provides an ideal access to restore signals of two related dictionaries and sparse representation. It has been proven that this method performs well in medical image reconstruction with highly undersampled data, especially for multimodality imaging like CT-MRI hybrid reconstruction. Because of its outstanding strength, short signal acquisition time, and low radiation dose, DDL has allured a broad interest in both academic and industrial fields. Here in this review article, we summarize DDL’s development history, conclude the latest advance, and also discuss its role in the future directions and potential applications in medical imaging. Meanwhile, this paper points out that DDL is still in the initial stage, and it is necessary to make further studies to improve this method, especially in dictionary training.
High Order Statistics and Time-Frequency Domain to Classify Heart Sounds for Subjects under Cardiac Stress Test
Authors: Moukadem Ali , Schmidt Samuel , Dieterlen Alain
Published: May 2015

This paper considers the problem of classification of the first and the second heart sounds (S1 and S2) under cardiac stress test. The main objective is to classify these sounds without electrocardiogram (ECG) reference and without taking into consideration the systolic and the diastolic time intervals criterion which can become problematic and useless in several real life settings as severe tachycardia and tachyarrhythmia or in the case of subjects being under cardiac stress activity. First, the heart sounds are segmented by using a modified time-frequency based envelope. Then, to distinguish between the first and the second heart sounds, new features, namedαopt,β, andγ, based on high order statistics and energy concentration measures of the Stockwell transform (S-transform) are proposed in this study. A study of the variation of the high frequency content of S1 and S2 over the HR (heart rate) is also discussed. The proposed features are validated on a database that contains 2636 S1 and S2 sounds corresponding to 62 heart signals and 8 subjects under cardiac stress test collected from healthy subjects. Results and comparisons with existing methods in the literature show a large superiority for our proposed features.
Comparison of Second-Line Quadruple Therapies with or without Bismuth forHelicobacter pyloriInfection
Authors: Jheng Guang-Hong , Wu I-Chen , Shih Hsiang-Yao , Wu Meng-Chieh , Kuo Fu-Chen , Hu Huang-Ming , Liu Chung-Jung , Hsu Wen-Hung , Hu Chi-Tan , Bair Ming-Jong , Kuo Chao-Hung , Wu Deng-Chyang , Hsu Ping-I
Published: May 2015

The bismuth-based quadruple regimen has been applied inHelicobacter pylorirescue therapy worldwide. The non-bismuth-based quadruple therapy or “concomitant therapy” is an alternative option in first-line eradication but has not been used in second-line therapy. Discovering a valid regimen for rescue therapy in bismuth-unavailable countries is important. We conducted a randomized controlled trial to compare the efficacies of the standard quadruple therapy and a modified concomitant regimen. One hundred and twenty-four patients were randomly assigned into two groups: RBTM (rabeprozole 20 mg bid., bismuth subcitrate 120 mg qid, tetracycline 500 mg qid, and metronidazole 250 mg qid) and RATM (rabeprozole 20 mg bid., amoxicillin 1 g bid., tetracycline 500 mg qid, and metronidazole 250 mg qid) for 10 days. The eradication rate of the RBTM and RATM regimen was 92.1% and 90.2%, respectively, in intention-to-treat analysis. Patients in both groups had good compliance (~96%). The overall incidence of adverse events was higher in the RATM group (42.6% versus 22.2%,P=0.02), but only seven patients (11.5%) experienced grades 2-3 events. In conclusion, both regimens had good efficacy, compliance, and acceptable side effects. The 10-day RATM treatment could be an alternative rescue therapy in bismuth-unavailable countries.
The Quantitative Measurement of Reversible Acute Depression after Subthalamic Deep Brain Stimulation in a Patient with Parkinson Disease
Authors: Simmons Daniel B. , Dashtipour Khashayar
Published: May 2015

Background. Depression is the most commonly reported mood symptom affecting 2–8% of patients after deep brain stimulation (DBS). Usually, symptoms develop gradually; however there have been cases of reproducible events that the mood symptoms were elicited within seconds to minutes after stimulation and were immediately reversible upon cessation of the stimulus. In the current study, we applied a self-reported questionnaire to assess the patient’s mood state.Objective. To objectively measure the reversible acute depression induced by DBS in a patient with Parkinson disease (PD).Methods. A statistically validated Spanish version of the Beck Depression Inventory Short Form (BDI-SF) was used. The questionnaire was administered three times.Results. The patient became acutely depressed within ninety seconds of monopolar stimulation on the right side. His symptoms resolved immediately after changing the setting to bipolar stimulation. The BDI-SF scores during stimulation off, on, and off again were 15, 19, and 6, respectively.Conclusions. The BDI-SF scores increased during stimulation and decreased after cessation. This is consistent with a reversible depressive state. The poststimulation BDI-SF score decreased to less than half of the baseline score. This may suggest that the depression was more severe than the patient was able to express during the stimulation.
Effects of Gray-Scale Ultrasonography Immediate Post-Contrast on Characterization of Focal Liver Lesions
Authors: Yang Wei , Chen Min-Hua , Wu Wei , Dai Ying , Fan Zhi-Hui
Published: May 2015

This study compared the imaging features of conventional gray scale ultrasound (US) before and after contrast-enhanced ultrasound (CEUS) for focal liver lesions and 22 evaluated the role of US post-CEUS in characterizing liver lesions. 126 patients with 158 focal liver lesions underwent CEUS and US post-CEUS examination and entered this study. There were 74 hepatocellular carcinomas (HCC), 43 hepatic metastases, and 41 hemangiomas. Imaging features of US pre-CEUS and US post-CEUS were analyzed offsite by two blinded experienced radiologists to evaluate size, boundary, echogenicity, internal texture, posterior acoustic enhancement, spatial resolution, and contrast resolution. In the end with pathological and clinical evidence, the diagnostic accuracy rate of US pre-CEUS was 53.8% (85/158 lesions), lower than that of CEUS (88.0%, 139/158 lesions); with the complementation of US post-CEUS the rate rose to 93.0% (147/158 lesions). US post-CEUS could improve the visibility of typical structures of focal liver lesions and might provide important complementary information for CEUS diagnosis. It also increases the visibility of small liver lesions compared with US pre-CEUS and helps to guide local interventional procedure.