bluuebunny/crossref_metadata_2025 huggingface dataset:
Reconstruction of sound source pressures in an enclosure using the phased beam tracing method
Authors: Jeong Cheol-Ho , Ih Jeong-Guon
Published: July 2009

Source identification in an enclosure is not an easy task due to complicated wave interference and wall reflections, in particular, at mid-high frequencies. In this study, a phased beam tracing method was applied to the reconstruction of source pressures inside an enclosure at medium frequencies. First, surfaces of an extended source are divided into reasonably small segments. From each source segment, one beam is projected into the field and all emitted beams are traced. Radiated beams from the source reach array sensors after traveling various paths including the wall reflections. Collecting all the pressure histories at the field points, source-observer relations can be constructed in a matrix-vector form for each frequency. By multiplying the measured field data with the pseudo-inverse of the calculated transfer function, one obtains the distribution of source pressure. An omni-directional sphere and a cubic source in a rectangular enclosure were taken as examples in the simulation tests. A reconstruction error was investigated by Monte Carlo simulation in terms of field point locations. When the source information was reconstructed by the present method, it was shown that the sound power of the source in an enclosure could be estimated.
Singing in congenital amusia
Authors: Dalla Bella Simone , Giguère Jean-François , Peretz Isabelle
Published: July 2009

Congenital amusia is a musical disorder characterized by impaired pitch perception. To examine to what extent this perceptual pitch deficit may compromise singing, 11 amusic individuals and 11 matched controls were asked to sing a familiar tune with lyrics and on the syllable /la/. Acoustical analysis of sung renditions yielded measures of pitch accuracy (e.g., number of pitch errors) and time accuracy (e.g., number of time errors). The results revealed that 9 out of 11 amusics were poor singers, mostly on the pitch dimension. Poor singers made an anomalously high number of pitch interval and contour errors, produced pitch intervals largely deviating from the score, and lacked pitch stability; however, more than half of the amusics sang in-time. Amusics’ variability in singing proficiency was related to their residual pitch perceptual ability. Thus, their singing deficiency might be a consequence of their perceptual deficit. Nevertheless, there were notable exceptions. Two amusic individuals, despite their impoverished perception, sang proficiently. The latter findings are consistent with the existence of separate neural pathways for auditory perception and action.
Underwater hearing sensitivity of harbor seals (Phoca vitulina) for narrow noise bands between 0.2 and 80 kHz
Authors: Kastelein Ronald A. , Wensveen Paul , Hoek Lean , Terhune John M.
Published: July 2009

The underwater hearing sensitivities of two 1.5-year-old female harbor seals were quantified in a quiet pool built specifically for acoustic research, by using a behavioral psychoacoustic technique. The animals were trained to respond when they detected an acoustic signal and not to respond when they did not (“go/no-go” response). Fourteen narrowband noise signals (1/3-octave bands but with some energy in adjacent bands), at 1/3-octave center frequencies of 0.2–80 kHz, and of 900 ms duration, were tested. Thresholds at each frequency were measured using the up-down staircase method and defined as the stimulus level resulting in a 50% detection rate. Between 0.5 and 40 kHz, the thresholds corresponded to a 1/3-octave band noise level of ∼60 dB re 1μPa (SD±3.0 dB). At lower frequencies, the thresholds increased to 66 dB re 1μPa and at 80 kHz the thresholds rose to 114 dB re 1μPa. The 1/3-octave noise band thresholds of the two seals did not differ from each other, or from the narrowband frequency-modulated tone thresholds at the same frequencies obtained a few months before for the same animals. These hearing threshold values can be used to calculate detection ranges of underwater calls and anthropogenic noises by harbor seals.
A versatile pitch tracking algorithm: From human speech to killer whale vocalizations
Authors: Shapiro Ari Daniel , Wang Chao
Published: July 2009

In this article, a pitch tracking algorithm [named discrete logarithmic Fourier transformation-pitch detection algorithm (DLFT-PDA)], originally designed for human telephone speech, was modified for killer whale vocalizations. The multiple frequency components of some of these vocalizations demand a spectral (rather than temporal) approach to pitch tracking. The DLFT-PDA algorithm derives reliable estimations of pitch and the temporal change of pitch from the harmonic structure of the vocal signal. Scores from both estimations are combined in a dynamic programming search to find a smooth pitch track. The algorithm is capable of tracking killer whale calls that contain simultaneous low and high frequency components and compares favorably across most signal to noise ratio ranges to the peak-picking and sidewinder algorithms that have been used for tracking killer whale vocalizations previously.
A numerical study of defect detection in a plaster dome ceiling using structural acoustics
Authors: Bucaro J. A. , Romano A. J. , Valdivia N. , Houston B. H. , Dey S.
Published: July 2009

A numerical study is carried out to evaluate the effectiveness of using measured surface displacements resulting from acoustic speaker excitation to detect and localize flaws in a domed, plaster ceiling. The response of the structure to an incident acoustic pressure is obtained at four frequencies between 100 and 400 Hz using a parallel h-p structural acoustic finite element-based code. Three ceiling conditions are modeled: the pristine ceiling considered rigidly attached to the domed-shape support, partial detachment of a segment of the plaster layer from the support, and an interior pocket of plaster deconsolidation modeled as a heavy fluid. Spatial maps of the normal displacement resulting from speaker excitation are interpreted with the help of predictions based on static analysis. It is found that acoustic speaker excitation can provide displacement levels readily detected by commercially available laser Doppler vibrometer systems. Further, it is concluded that for 1 in. thick plaster layers, detachment sizes as small as 4 cm are detectable by direct observation of the measured displacement maps. Finally, spatial structure differences are observed in the displacement maps beneath the two defect types, which may provide a wavenumber-based feature useful for distinguishing plaster detachment from other defects such as deconsolidation.
Closure duration analysis of incomplete stop consonants due to stop-stop interaction
Authors: Ghosh Prasanta Kumar , Narayanan Shrikanth S.
Published: July 2009

An incomplete stop consonant is characterized either by an indistinguishable closure or a missing burst. If an incomplete stop happens due to a stop following another stop [stop-stop interaction (SSI)], its acoustics typically resemble that of a complete stop—one closure followed by a single burst. As a consequence, stop detectors would fail to distinguish an SSI from a complete stop. Analysis of the TIMIT corpus shows 35.04% incomplete stops (14.97% SSI). It is shown that by using automatically estimated (and hand-labeled) closure duration, complete stops can be distinguished from incomplete stops due to SSI with 69.66% (79.14%) accuracy.
Use of forward pressure level to minimize the influence of acoustic standing waves during probe-microphone hearing-aid verification
Authors: McCreery Ryan W. , Pittman Andrea , Lewis James , Neely Stephen T. , Stelmachowicz Patricia G.
Published: July 2009

Probe-microphone measurements are a reliable method of verifying hearing-aid sound pressure level (SPL) in the ear canal for frequencies between 0.25 and 4 kHz. However, standing waves in the ear canal reduce the accuracy of these measurements above 4 kHz. Recent data suggest that speech information at frequencies up to 10 kHz may enhance speech perception, particularly for children. Incident and reflected components of a stimulus in the ear canal can be separated, allowing the use of forward (incident) pressure as a measure of stimulus level. Two experiments were conducted to determine if hearing-aid output in forward pressure provides valid estimates of in-situ sound level in the ear canal. In experiment 1, SPL measurements were obtained at the tympanic membrane and the medial end of an earmold in ten adults. While within-subject test-retest reliability was acceptable, measures near the tympanic membrane reduced the influence of standing waves for two of the ten participants. In experiment 2, forward pressure measurements were found to be unaffected by standing waves in the ear canal for frequencies up to 10 kHz. Implications for clinical assessment of amplification are discussed.
A method for time-varying annoyance rating of aircraft noise
Authors: Dickson Crispin
Published: July 2009

The method of continuous judgment by category is used and evaluated to measure time-varying attributes in aircraft flyover sounds. The results are also used to estimate preference between the different experimental sounds. Jurors were asked to rate perceived annoyance on a Borg CR 100 scale continuously during the playback of 11 flyover sequences and the results showed differences in perception in the time segment where the sound had been modified. The method can be used to evaluate maximum perceived annoyance, threshold levels, duration of perceptual presence temporal integration in perception, and perceptual mixtures over time.
Analyzing lateral seabed variability with Bayesian inference of seabed reflection data
Authors: Dettmer Jan , Holland Charles W. , Dosso Stan E.
Published: July 2009

This paper considers Bayesian inversion of seabed reflection-coefficient data for multi-layer geoacoustic models at several sites, with the goal of studying lateral variability of the seabed. Rigorous uncertainty estimation is carried out to resolve lateral variability of the sediments from inherent inversion uncertainties. The uncertainty analysis includes Bayesian model selection, comprehensive quantification of data error statistics, and a Markov-chain Monte Carlo approach to transforming data uncertainties to model uncertainties. Model selection is addressed using the Bayesian information criterion to ensure parsimony of the parametrizations. Data error statistics are quantified by estimating full covariance matrices from data residuals, with posterior statistical validation. A Metropolis–Hastings sampling algorithm is used to compute posterior probability densities. Four experiment sites are considered along a track located on the Malta Plateau, Mediterranean Sea, and the inversion results are compared to cores taken at each site. Differences between profile marginal-probability distributions at adjacent sites are quantified using the Bhattacharyya coefficient. Differences that exceed the estimated geoacoustic uncertainties are interpreted as spatial variability of the seabed. The results are compared to an interpretation of geologic features evident in a chirp sub-bottom-profiler section.
Multiple acoustic diffraction around rigid parallel wide barriers
Authors: Min Hequn , Qiu Xiaojun
Published: July 2009

A ray-based method is presented for evaluating multiple acoustic diffraction by separate rigid and parallel wide barriers, where two or more neighboring ones are of equal height. Based on the geometrical theory of diffraction and extended from the exact boundary solution for a rigid wedge, the proposed method is able to determine the multiple diffraction along arbitrary directions or at arbitrary receiver locations around the diffracting edges, including the positions along the shadow or reflection boundaries or very close to the edges. Comparisons between the results of the numerical simulations and the boundary element method show validity of the proposed method.
Acoustic basis for fish prey discrimination by echolocating dolphins and porpoises
Authors: Au Whitlow W. L. , Branstetter Brian K. , Benoit-Bird Kelly J. , Kastelein Ronald A.
Published: July 2009

The biosonar system of dolphins and porpoises has been studied for about 5decades and much has been learned [Au, W. W. L. (1993). The Sonar of Dolphins (Springer, New York)]. Most experiments have involved human-made targets; little is known about odontocetes’ echolocation of prey. To address this issue, acoustic backscatter from Atlantic cod (Gadus morhua), gray mullet (Chelon labrosus), pollack, (Pollachius pollachius), and sea bass (Dicentrarchus labrax) was measured using simulated biosonar signals of the Atlantic bottlenose dolphin and harbor porpoise. The fish specimens were rotated so that the effects of the fish orientation on the echoes could be determined. Echoes had the highest amplitude and simplest structure when the incident angle was perpendicular to the longitudinal axis of the fish. The complexity of the echoes increased as the aspect angle of the fish moved away from the normal aspect. The echoes in both the time and frequency domains were easily distinguishable among the four species of fish and were generally consistent within species. A cochlear model consisting of a bank of band-passed filters was also used to analyze the echoes. The overall results suggest that there are sufficient acoustic cues available to discriminate between the four species of fish based on the echoes received, independent of aspect angle.
Evaluating standard airborne sound insulation measures in terms of annoyance, loudness, and audibility ratings
Authors: Park H. K. , Bradley J. S.
Published: July 2009

This paper reports the results of an evaluation of the merits of standard airborne sound insulation measures with respect to subjective ratings of the annoyance and loudness of transmitted sounds. Subjects listened to speech and music sounds modified to represent transmission through 20 different walls with sound transmission class (STC) ratings from 34 to 58. A number of variations in the standard measures were also considered. These included variations in the 8-dB rule for the maximum allowed deficiency in the STC measure as well as variations in the standard 32-dB total allowed deficiency. Several spectrum adaptation terms were considered in combination with weighted sound reduction index (Rw) values as well as modifications to the range of included frequencies in the standard rating contour. A STC measure without an 8-dB rule and an Rw rating with a new spectrum adaptation term were better predictors of annoyance and loudness ratings of speech sounds. Rw ratings with one of two modified Ctr spectrum adaptation terms were better predictors of annoyance and loudness ratings of transmitted music sounds. Although some measures were much better predictors of responses to one type of sound than were the standard STC and Rw values, no measure was remarkably improved for predicting annoyance and loudness ratings of both music and speech sounds.
Energy equipartition and frequency distribution in complex attachments
Authors: Roveri N. , Carcaterra A. , Akay A.
Published: July 2009

As reported in several recent publications, an undamped simple oscillator with a complex attachment that consists of a set of undamped parallel resonators can exhibit unusual energy sharing properties. The conservative set of oscillators of the attachment can absorb nearly all the impulsive energy applied to the primary oscillator to which it is connected. The key factor in the ability of the attachment to absorb energy with near irreversibility correlates with the natural frequency distribution of the resonators within it. The reported results also show that a family of optimal frequency distributions can be determined on the basis of a variational approach, minimizing a certain functional related to the system response. The present paper establishes a link between these optimal frequency distributions and the energy equipartition principle: optimal frequency distributions are those that spread the injected energy as uniformly as possible over the degrees of freedom or over the modes of the system. Theoretical as well as numerical results presented support this point of view.
Detection of the break in interaural correlation is affected by interaural delay, aging, and center frequency
Authors: Huang Ying , Wu Xihong , Li Liang
Published: July 2009

This study investigated whether interaural integration is affected by introducing an interaural delay. In Experiment 1, both younger adults with normal hearing and older adults in the early stages of presbycusis were able to detect a transient break in interaural correlation (BIC) in the temporal middle of interaurally correlated wideband noises. However, their duration thresholds for detecting the BIC became larger with increasing interaural time difference (ITD) from 0 to 6 ms, and the threshold increase for older participants was larger than that for younger participants. In Experiment 2, to investigate whether the effect of changing ITD on the BIC detection is frequency-dependent, 1/3-octave narrowband noises with various center frequencies were used as stimuli. Results show that the duration threshold for detecting the BIC was higher for high-frequency noises than for low-frequency noises. Also, with increasing ITD from 0 to 4 ms, the threshold increase was larger for high-frequency noises than for low-frequency noises. The results suggest that there are age- and frequency-related temporal declines in maintaining fine-structure signals for interaural integration. These declines may affect the recognition of sound sources in reverberant environments.
Localization and tracking of phonating finless porpoises using towed stereo acoustic data-loggers
Authors: Li Songhai , Akamatsu Tomonari , Wang Ding , Wang Kexiong
Published: July 2009

Cetaceans produce sound signals frequently. Usually, acoustic localization of cetaceans was made by cable hydrophone arrays and multichannel recording systems. In this study, a simple and relatively inexpensive towed acoustic system consisting of two miniature stereo acoustic data-loggers is described for localization and tracking of finless porpoises in a mobile survey. Among 204 porpoises detected acoustically, 34 individuals (∼17%) were localized, and 4 of the 34 localized individuals were tracked. The accuracy of the localization is considered to be fairly high, as the upper bounds of relative distance errors were less than 41% within 173 m. With the location information, source levels of finless porpoise clicks were estimated to range from 180 to 209 dB re 1 μPa pp at 1 m with an average of 197 dB (N=34), which is over 20 dB higher than that estimated previously from animals in enclosed waters. For the four tracked porpoises, two-dimensional swimming trajectories relative to the moving survey boat, absolute swimming speed, and absolute heading direction are deduced by assuming the animal movements are straight and at constant speed in the segment between two consecutive locations.
Voice of the turtle: The underwater acoustic repertoire of the long-necked freshwater turtle, Chelodina oblonga
Authors: Giles Jacqueline C. , Davis Jenny A. , McCauley Robert D. , Kuchling Gerald
Published: July 2009

Chelodina oblonga is a long-necked, freshwater turtle found predominantly in the wetlands on the Swan Coastal Plain of Western Australia. Turtles from three populations were recorded in artificial environments set up to simulate small wetlands. Recordings were undertaken from dawn to midnight. A vocal repertoire of 17 categories was described for these animals with calls consisting of both complex and percussive spectral structures. Vocalizations included clacks, clicks, squawks, hoots, short chirps, high short chirps, medium chirps, long chirps, high calls, cries or wails, hooos, grunts, growls, blow bursts, staccatos, a wild howl, and drum rolling. Also, a sustained vocalization was recorded during the breeding months, consisting of pulse sequences that finished rhythmically. This was hypothesized to function as an acoustic advertisement display. Chelodina oblonga often lives in environments where visibility is restricted due to habitat complexity or poor light transmission due to tannin-staining or turbidity. Thus the use of sound by turtles may be an important communication medium over distances beyond their visual range. This study reports the first records of an underwater acoustic repertoire in an aquatic chelonian.
Temporal sound field fluctuations in the presence of internal solitary waves in shallow water
Authors: Katsnelson Boris G. , Grigorev Valery , Badiey Mohsen , Lynch James F.
Published: July 2009

Temporal variations of intensity fluctuations are presented from the SWARM95 experiment. It is hypothesized that specific features of these fluctuations can be explained by mode coupling due to the presence of an internal soliton moving approximately along the acoustic track. Estimates are presented in conjunction with theoretical consideration of the shallow water waveguide.
Synthesis of unsymmetric cyanine dye via merocyanine and their interaction with DNA
Authors: Bříza Tomáš , Kejík Zdeněk , Králová Jarmila , Martásek Pavel , Král Vladimír
Published: July 2009

An effective method has been developed for synthesis of neutral merocyanine dye 4 from (4-nitrophenyl)malondialdehyde. Merocyanine 4 was used as a basic building block for preparation of unsymmetric cyanine dyes 9 and 10, both derived from the same aromatic malondialdehyde. With the cyanine 10, pH-dependent affinity to DNA has been studied. Unsymmetric cyanine dye 10 has been compared with symmetric dye 8. The corresponding binding constants (K) have been calculated for various pH.
Atrial fibrillation in endurance-trained athletes: Table 1
Authors: Sorokin A V , Araujo C G S , Zweibel S , Thompson P D
Published: July 2009

Background

Endurance exercise training produces multiple cardiac adaptations including changes in electrophysiological function that may make endurance-trained athletes more vulnerable to atrial fibrillation (AF). This possible association is not recognised by many practising cardiologists and sports physicians. Consequently, we performed a literature review to examine the relationship between atrial fibrillation and endurance exercise training among athletes. PubMed was searched from January 1960 through December 2008 to identify articles examining the relationship between endurance exercise training and AF.

Results

Evidence suggests that athletes are at increased risk for development of AF. Possible factors increasing AF in this population include increased parasympathetic tone, reduced sympathetic tone, increased atrial size and increased inflammation.

Discussion

Suggested management of AF in athletes should follow similar principles to those used to manage AF in the general population.
The Efficacy of Kiko Exercises on the Prevention of Migraine Headaches: A Pilot Study
Authors: Elinoff Victor , Lynn Steven Jay , Ochiai Hidy , Hallquist Michael
Published: July 2009

Migraine headaches, a common chronic medical problem, require prophylactic treatment when they are frequent and severe. This is the first study to investigate the efficacy of Kiko, a Japanese practice of Qigong that uses repetitive coordinated breathing and movement as a prophylactic treatment of migraine headaches. This pilot study, a single arm, non-randomized 4-month trial, investigated whether 3 months of Kiko training would reduce the severity and/or frequency of migraine and/or MIDAS scores. The baseline migraine data were collected from participants in the first month and then participants were taught Kiko exercises in 3 monthly sessions. Participants practiced at home and had the opportunity to utilize a Kiko DVD. The participants were instructed by Washin-Ryu style martial arts Master, Hidy Ochiai. Subjects completed monthly diaries that recorded the frequency and severity of their migraines, as well as the frequency and duration of their home Kiko practice. Six of the original 13 subjects completed the trial. All the individuals who completed the study had measurable improvement in their migraines. All participants reported a positive experience in learning the technique, and there were no reported adverse effects. Although the results of this study need to be confirmed in a larger clinical trial with adequate controls for placebo effects, these preliminary results are consistent with other trials that have documented the potential benefits of mind-body practices in controlling symptoms and improving the quality of life of patients suffering from chronic medical illness.
Effects of Acupuncture Stimulation on Recovery Ability of Male Elite Basketball Athletes
Authors: Lin Zen-Pin , Lan Lawrence W. , He Tsung-Ying , Lin Shi-Pin , Lin Jang-Geng , Jang Tsong-Rong , Ho Tsung-Jung
Published: July 2009

Developing effective methods for helping athletes recover from muscle fatigue is deemed essential, particularly on the eves' important competitions. This study aimed to investigate the effects of acupuncture stimulation on athletes' recovery abilities. Subjects were selected from 30 male elite university basketball players who were randomly assigned to 3 groups: acupuncture group, sham group, and normal (control) group, each containing 10 subjects. Acupuncture was carried out on each athlete in acupuncture group at the Neiguan (PC6) and Zusanli (ST36) acupoints, beginning at 15 min prior to exercise and continuing until exhaustion of the subject. Similar acupuncture was also carried out on each athlete in the sham group but the positions were 1 cm away from the PC6 and ST36 acupoints. No acupuncture was conducted on the athletes in the normal group. During the experiments, each subject performed separate runs on the treadmill. The data of heart rate (HRmax), oxygen consumption (VO2max), and blood lactic acid were measured during the rest period and at 3 recovery points of time (5th, 30th and 60th min) post-exercise. The results showed that the acupuncture group (PC6 and ST36) has significantly lower HRmax, VO2max and blood lactic acid than both the sham and normal groups at the 30th min post-exercise. Blood lactic acid of the acupuncture group was also significantly lower than that of the other two groups in the 60th min post-exercise. Our findings have shed some light on the development of effective acupuncture schemes to enhance the recovery ability for elite basketball athletes.
Protective Effect ofOriganum majoranaL. 'Marjoram' on Various Models of Gastric Mucosal Injury in Rats
Authors: Al-Howiriny Tawfeq , Alsheikh Abdulmalik , Alqasoumi Saleh , Al-Yahya Mohammed , ElTahir Kamal , Rafatullah Syed
Published: July 2009

'Marjoram,' Origanum majorana L., a culinary aromatic medicinal herb is known to possess various therapeutic properties. We evaluated the antiulcerogenic activity of the ethanol extract in hypothermic restraint stress-, indomethacin-, necrotizing agents- (80% ethanol, 25% NaCl and 0.2 M NaOH ) induced ulcers and basal gastric acid secretion using pylorus ligated Shay rat-model. Marjoram at doses of 250 and 500 mg/kg of body weight, significantly decreased the incidence of ulcers, basal gastric secretion and acid output. Furthermore, the extract replenished the ethanol-induced depleted gastric wall mucus and nonprotein sulfhydryls (NP-SH) contents and significantly lowered the increase in the concentration of malondialdehyde (MDA). Ulcer preventing potential was further confirmed by histopathological assessment. An acute toxicity test showed a large margin of safety of the extract in mice. The phytochemical screening of aerial parts of marjoram revealed the presence of volatile oil, flavonoids, tannins, sterols and/or triterpenes.
ChronicRhodiola roseaExtract Supplementation Enforces Exhaustive Swimming Tolerance
Authors: Lee Fang-Tsai , Kuo Tz-Yin , Liou Shaw-Yih , Chien Chiang-Ting
Published: July 2009

We explored the effects and mechanisms of Rhodiola rosea extract supplementation on swimming-induced fatigue in rats. The concentrations of active components in Rhodiola rosea have been determined by high performance liquid chromatography-mass spectrometer. The Rhodiola rosea extract supplementation in water for 2–4 weeks was evaluated in male Wistar rats with 90-min unloaded swimming exercise and 5% body weight loaded swimming up to fatigue. We measured the fatigue biomarkers, including blood urea nitrogen (BUN), glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT), lactate dehydrogenase (LDH), hepatic glycogen content, the activity of fat metabolism enzymes, sterol regulatory element-binding protein-1 (SREBP-1) and fatty acid synthase (FAS), the tissue oxygen content and ratio of red and white skeletal muscle fibers in rats. Rhodiola rosea significantly increased liver glycogen, SREBP-1, FAS, heat shock protein 70 expression, Bcl-2/Bax ratio and oxygen content before swimming. Rhodiola rosea supplementation significantly increased the swimming time in a dose-dependent manner and reduced swimming-enhanced serum BUN, GOT and GPT levels. The ratio of red and white muscle fibers was not altered after chronic Rhodiola rosea extract supplementation. Chronic Rhodiola rosea supplementation significantly improved exhaustive swimming-induced fatigue by the increased glycogen content, energy supply of lipogenic enzyme expressions and protective defense mechanisms.
Analgesic and Anti-Inflammatory Activities of Methanol Extract fromDesmodium triflorumDC in Mice
Authors: Lai Shang-Chih , Peng Wen-Huang , Huang Shun-Chieh , Ho Yu-Ling , Huang Tai-Hung , Lai Zhen-Rung , Chang Yuan-Shiun
Published: July 2009

In this study, we evaluated the analgesic effect of methanol extract from Desmodium triflorum DC (MDT) by using animal models of acetic acid-induced writhing response and formalin test. The anti-inflammatory effect of MDT was investigated by λ-carrageenan-induced paw edema in mice. In order to study the anti-inflammatory mechanism of MDT, we detected the activities of glutathione peroxidase (GPx) and glutathione reductase (GRd) in the liver, the levels of interleukin-1β (IL-1β), tumor necrosis factor (TNF-α), malondialdehyde (MDA) and nitric oxide (NO) in the edema paw tissue. In the analgesic test, MDT (0.5 and 1.0 g/kg) decreased the acetic acid-induced writhing response and the licking time on the late phase in the formalin test. In the anti-inflammatory test, MDT (0.5 and 1.0 g/kg) decreased the paw edema at the 3rd, 4th, 5th and 6th hour after λ-carrageenan administration. On the other hand, MDT increased the activities of SOD and GRd in liver tissues and decreased the MDA level in the edema paw at the 3rd hour after λ-carrageenan-induced inflammation. MDT also affected the levels of interleukin-1β, tumor necrosis factor-α, NO and MDA which were induced by λ-carrageenan. The results suggested that MDT possessed analgesic and anti-inflammatory effects. The anti-inflammatory mechanism of MDT might be related to the decreases in the level of MDA in the edema paw via increasing the activities of SOD and GRd in the liver, and the NO level via regulating the IL-1β production and the level of TNF-α in the inflamed tissues.
Selective Cytotoxic Effects on Human Cancer Cell Lines of Phenolic-Rich Ethyl-Acetate Fraction from Rhus verniciflua Stokes
Authors: Kim Ji Hye , Jung Chang Hwa , Jang Bo-Hyoung , Go Ho Yeon , Park Jong-Hyeong , Choi You-Kyung , Hong Seong Il , Shin Yong Cheol , Ko Seong-Gyu
Published: July 2009

Rhus verniciflua Stokes (RVS) is a plant with a long history of medicinal use in Eastern Asia. RVS has been widely used to treat gastritis, stomach cancer and atherosclerosis. The cytotoxic effects of different solvent fractions from an RVS ethanol extract were measured in 11 human cancer cell lines. The study showed that the ethyl-acetate (EtOAC) fraction was the most cytotoxic. This fraction contains a number of phenolic compounds, and this phenolic-rich EtOAC fraction was particularly effective against gastric and breast cancer cells. A purified phenolic-rich EtOAC fraction (PPEF) had a stronger apoptotic effect on these cells. Liquid chromatography-mass spectrometry (LC-MS) analysis showed that the PPEF contained gallic acid, protocatechuic acid, fisetin, sulfuretin, butein and 8 unknown compounds. There were only small amounts of flavonoids: fisetin, sulfuretin and butein. The results showed that PPEF induces apoptosis only in gastric and breast cancer cell lines, but not in lung, colon or liver cancer cell lines. Therefore, PPEF may have a significant potential as an organ-specific anti-cancer agent.
EFFECT OF TEMPERATURE ON SELF-ASSEMBLY OF DIAMOND-LIKE CARBON (DLC) GROWN BY PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION (PECVD)
Authors: MAHAPATRA OJAS , MAHESWARAN R. , KUMAR N. SATYA VIJAYA , GANESH K. R. , GOPALAKRISHNAN C. , THIRUVADIGAL D. JOHN , RAJA S. V. KASMIR
Published: July 2009

Diamond-like carbon nanostructures were prepared using Plasma enhanced chemical vapor deposition (PECVD). Temperature dependence of self-assembly of carbon nanostructures is noted. Carbon and silicon exhibit significant lattice mismatch and during the self-assembly, stacking of carbon atoms takes place which results in conic projections. The carbon nanostructures were prepared at 600°C and 100 W RF power and were subjected to a cooling treatment. Argon and Methane were used as reactant gases. The formation of nanostructures did not use any catalyst. The surface morphology and roughness analysis was carried by Atomic Force microscopy. The nanocones were characterized by X Ray Diffractometer and Raman Spectroscopy.
SURFACE PHONON–POLARITON MODES OF WURTZITE STRUCTURE InN SEMI-INFINITE CRYSTAL
Authors: NG S. S. , HASSAN Z. , HASSAN H. ABU
Published: July 2009

In this paper, theoretical study on the surface phonon–polariton (SPP) modes of wurtzite (α-) structure indium nitride ( InN ) semi-infinite crystal is presented. Based on an anisotropy model, the surface polariton (SP) dispersion curve of α- InN is simulated. The characteristics of this dispersion curve are discussed. The relevant experimental information by attenuated total reflection method is given. For comparison, the SP dispersion curve of cubic (β-) structure InN simulated based on isotropy model is also presented. Due to optical anisotropic, the SP dispersion curve of α- InN exhibits an extra branch as well as an extra SPP mode as compared to α- InN . In addition, the SPP mode of α- InN is found to be 4 cm-1 smaller than that of β- InN .
THE ROLE OF ARTIFICIAL POLARIZATION IN OPTICAL PROPERTIES OF FA2:Sr2+ CENTER AND NO INTERACTIONS AT RbCl (001) SURFACE: AN AB INITIO STUDY
Authors: ASSEM MERVAT M.
Published: July 2009

The role of artificial polarization in two different applications of the title color center, namely optical properties of F A 2: Sr 2+ center and adsorbate–substrate interactions, is investigated by using quantum mechanical CI-singles and DFT ab initio methods. Clusters of variable sizes were embedded in the simulated Coulomb field that closely approximate the Madelung field of the host surface, and ions that were the nearest neighbors to the defect site were allowed to relax to equilibrium. The sensitivity of the calculated transition energies (Stokes shifts) of F A 2: Sr 2+ center as well as related optical properties, such as optical–optical conversion efficiency, relaxed excited states of the defect-containing surface, orientational destruction of the point defect, recording sensitivity, the Glasner–Tompkins empirical rule, and the artificial polarization were examined. The dependence of NO and ON adsorption energies at RbCl (001) surface on artificial polarization were also examined, and the results were explained in terms of electrostatic potential curves. The coadsorption of NO molecules, and the charge transfer reactions between the NO molecules and the paramagnetic chlorine vacancy on RbCl surface were considered.
Low-power FinFET circuit synthesis using multiple supply and threshold voltages
Authors: Mishra Prateek , Muttreja Anish , Jha Niraj K.
Published: July 2009

According to Moore's law, the number of transistors in a chip doubles every 18 months. The increased transistor-count leads to increased power density. Thus, in modern circuits, power efficiency is a central determinant of circuit efficiency. With scaling, leakage power accounts for an increasingly larger portion of the total power consumption in deep submicron technologies (>40%).

FinFET technology has been proposed as a promising alternative to deep submicron bulk CMOS technology, because of its better scalability, short-channel characteristics, and ability to suppress leakage current and mitigate device-to-device variability when compared to bulk CMOS. The subthreshold slope of a FinFET is approximately 60mV which is close to ideal.

In this article, we propose a methodology for low-power FinFET based circuit synthesis. A mechanism called TCMS (Threshold Control through Multiple Supply Voltages) was previously proposed for improving the power efficiency of FinFET based global interconnects. We propose a significant generalization of TCMS to the design of any logic circuit. This scheme represents a significant divergence from the conventional multiple supply voltage schemes considered in the past. It also obviates the need for voltage level-converters. We employ accurate delay and power estimates using table look-up methods based on HSPICE simulations for supply voltage and threshold voltage optimization. Experimental results demonstrate that TCMS can provide power savings of 67.6% and device area savings of 65.2% under relaxed delay constraints. Two other variants of TCMS are also proposed that yield similar benefits. We compare our scheme to extended cluster voltage scaling (ECVS), a popular dual-

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scheme presented in the literature. ECVS makes use of voltage level-converters. Even when it is assumed that these level-converters have zero delay, thus significantly favoring ECVS in time-constrained power optimization, TCMS still outperforms ECVS.
MulTFRC
Authors: Damjanovic Dragana , Welzl Michael
Published: July 2009

When data transfers to or from a host happen in parallel, users do not always consider them to have the same importance. Ideally, a transport protocol should therefore allow its users to manipulate the fairness among flows in an almost arbitrary fashion. Since data transfers can also include real-time media streams which need to keep delay | and hence buffers | small, the protocol should also have a smooth sending rate. In an effort to satisfy the above requirements, we present MulTFRC, a congestion control mechanism which is based on the TCP-friendly Rate Control (TFRC) protocol. It emulates the behavior of a number of TFRC flows while maintaining a smooth sending rate. Our simulations and a real-life test demonstrate that MulTFRC performs significantly better than its competitors, potentially making it applicable in a broader range of settings than what TFRC is normally associated with.
Medium access controlfacing the reality of WSN deployments
Authors: Kuntz Romain , Gallais Antoine , Noel Thomas
Published: July 2009

Although research on algorithms and communication protocols in Wireless Sensor Networks (WSN) has yielded a tremendous effort so far, most of these protocols are hardly used in real deployments nowadays. Several reasons have been put forward in recent publications. In this paper, we further investigate this trend from a Medium Access Control (MAC) perspective by analyzing both the reasons behind successful deployments and the characteristics of the MAC layers proposed in the literature. The effort allocated to develop suitable protocols from scratch every new deployment could however be minimized by using already existing contributions which provide code reuse and adaptive protocols. Though we advocate their use for nowadays deployments, we have identified several shortcomings in foreseen scenarios for which we provide guidelines for future researches.
An update on the GENI project
Authors: Elliott Chip , Falk Aaron
Published: July 2009

Environment for Network Innovations. Early prototypes of GENI are starting to come online as an end-to-end system and network researchers are invited to participate by engaging in the design process or using GENI to conduct experiments.
Gemini Fiber for Interferometry and Sensing Applications
Authors: Zetterlund E. , Loriette A. , Sterner C. , Eriksson M. , Eriksson-Quist H. , Margulis W.
Published: July 2009

A novel type of fiber for sensing applications is introduced based on a plurality of individual fiber preforms drawn together but maintaining their original shape. The individual cores of the Gemini fiber can be addressed at input and output ends through splicing to stand‐alone fibers. Thermal coupling between cores is sufficient to eliminate relative thermal effects. Fabrication, coupling and fiber Bragg grating (FBG) studies are discussed. The possibility to connect in a single splice more than one fiber to the Gemini fiber is introduced as being highly advantageous. A conventional splicer can be used, the loss is acceptable and the operation takes minutes. Sensing with Gemini fibers is discussed mainly with the incorporation of fiber Bragg gratings. Another advantage of the concept of the Gemini fiber discussed is the possibility to make monolithic fiber interferometers of nearly equal arm lengths. A large number of new options are opened by the monolithic multicore fiber design, where access to individual cores is straightforward.
The Existence of Positive Solution to Three‐Point Singular Boundary Value Problem of Fractional Differential Equation
Authors: Tian Yuansheng , Chen Anping
Published: July 2009

We investigate the existence of
positive solution to nonlinear fractional differential equation
three‐point singular boundary value problem:
Dqu(t) + f(t, u(t)) = 0, 0 < t < 1, u(0) = 0, u(1) = αD(q−1)/2u(t)|t=ξ, where 1 < q ≤ 2 is a real number, ξ ∈ (0, 1/2], α ∈ (0, +∞) and αΓ(q)ξ(q−1)/2 < Γ((q + 1)/2), Dq is the standard Riemann‐Liouville fractional derivative, and f ∈ C((0, 1] × [0, +∞), [0, +∞)), lim t→+0f(t, ⋅) = +∞ (i.e., f is singular at t = 0). By using
the fixed‐point index theory, the existence result of positive
solutions is obtained.
Regulation of Bile Acid and Cholesterol Metabolism by PPARs
Authors: Li Tiangang , Chiang John Y. L.
Published: July 2009

Bile acids are amphipathic molecules synthesized from cholesterol in the liver. Bile acid synthesis is a major pathway for hepatic cholesterol catabolism. Bile acid synthesis generates bile flow which is important for biliary secretion of free cholesterol, endogenous metabolites, and xenobiotics. Bile acids are biological detergents that facilitate intestinal absorption of lipids and fat‐soluble vitamins. Recent studies suggest that bile acids are important metabolic regulators of lipid, glucose, and energy homeostasis. Agonists of peroxisome proliferator‐activated receptors (PPARα, PPARγ, PPARδ) regulate lipoprotein metabolism, fatty acid oxidation, glucose homeostasis and inflammation, and therefore are
used as anti‐diabetic drugs for treatment of dyslipidemia and insulin insistence. Recent studies have shown that activation of
PPARα alters bile acid synthesis, conjugation, and transport, and also cholesterol synthesis, absorption and reverse cholesterol transport. This review will focus on the roles of PPARs in the regulation of pathways in bile acid and cholesterol homeostasis, and the therapeutic implications of using PPAR agonists for the treatment of metabolic syndrome.
Synthesis of a New Calix[4]Arene and Its Application in Construction of a Highly Selective Silver Ion-Selective Membrane Electrode
Authors: Taghvaei-Ganjali Saeed , Zadmard Reza , Zeyaei Masoumeh , Rahnama Kabeh , Faridbod Farnoush , Ganjali Mohammad Reza
Published: July 2009

A PVC membrane sensor for Ag (I) ions has been prepared. The membrane has 5, 11, 17, 23-tetra-tert-butyl-25-(3-N, N-diethyldithio carbamoylpropoxy)-26,27,28-tris-propoxy calix[4]arene (CAD) as a carrier. It was found that the sensor exhibits a Nernstian response for Ag+ ions over a wide concentration range (10−2–10−6 M). Additionally, it illustrates a fast response time (about 5 seconds), and it can be used for at least 2 months without any considerable divergence in potentials. The nature of the plasticizer, the additive, the concentration of internal solutions in the electrodes, and the composition of the membrane were investigated. Furthermore, the suggested membrane electrode revealed good selectivities for Ag+ over a variety of other metal cations, and it could be used in the pH range of 3.0–7.0. Eventually, it was successfully applied as an indicator electrode for the potentiometric titration of Ag+ ion with NaCl.
Interior Controllability of a Broad Class of Reaction Diffusion Equations
Authors: Leiva Hugo , Quintana Yamilet
Published: July 2009

We prove the interior approximate controllability of the following broad class of reaction diffusion equation in the Hilbert spaces Z = L2(Ω) given by z′ = −Az + 1ωu(t), t ∈ [0, τ], where Ω is a domain in ℝn, ω is an open nonempty subset of Ω, 1ω denotes the characteristic function of the set ω, the distributed control u ∈ L2(0, t1; L2(Ω)) and A : D(A) ⊂ Z → Z is an unbounded linear operator with the following spectral decomposition: 〈z, ϕj,k〉ϕj,k. The eigenvalues 0 < λ1 < λ2 < ⋯<⋯λn → ∞ of A have finite multiplicity γj equal to the dimension of the corresponding eigenspace, and {ϕj,k} is a complete orthonormal set of eigenvectors of A. The operator −A generates a strongly continuous semigroup {T(t)} given by 〈z, ϕj,k〉ϕj,k. Our result can be applied to the nD heat equation, the Ornstein‐Uhlenbeck equation, the Laguerre equation, and the Jacobi equation.
Vibration Control of Manipulators with Flexible Nonprismatic Links Using Piezoelectric Actuators and Sensors
Authors: Bottega Valdecir , Molter Alexandre , Fonseca Jun S. O. , Pergher Rejane
Published: July 2009

This work presents a tracking control model for a flexible nonprismatic link
robotic manipulator using simultaneously motor torques and piezoelectric actuators. The dynamic model of the flexible manipulator is obtained in a closed form through the Lagrange equations. The control uses the motor torques for the joints tracking control and also to reduce the low‐frequency vibration induced in the manipulator links. The stability of this control is guaranteed by the Lyapunov stability theory. Piezoelectric actuators and sensors are added for controlling vibrations with frequencies beyond the reach of motor torque control. The naturals frequencies are calculated by the finite element method, and the approximated eigenfunctions are interpolated by polynomials. Three eigenfunctions are used for the dynamics of the arm, while only two are used for the control. Numerical experiments on Matlab/Simulink are used to verify the efficiency of the control model.