bluuebunny/crossref_metadata_2025 huggingface dataset:
Fire tolerance of three tree species in pine - oak forests of Chignahuapan, Puebla, Mexico
Authors: Bravo Juana E. Juárez , Rodríguez-Trejo Dante A. , Myers Ronald L.
Published: July 2012

Resprouting is a common recovery strategy of many tree and shrub species in fire-prone environments and is an important determinant of post-fire dominance and vegetation dynamics in many ecosystems. Top-kill, mortality and resprouting of the trees Quercus crassifolia, Arbutus xalapensis and Pinus teocote were studied on contiguous burned and unburned sites in the pine–oak forests of Chignahuapan, Puebla, Mexico. The study sample consisted of 375 individual trees, 199 on the burned site and 176 on the unburned site. T-tests and logistic regression were used in the statistical analysis. The number of resprouts per tree increased significantly (P < 0.001) in the broadleaved species, but not in the pine species. On the sites affected by fire, the smaller the diameter and higher the extent of top-kill in Q. crassifolia, the greater the probability of resprouting. None of the species exhibited differences in mortality (P > 0.05) regardless of fire or lack of fire. With Q. crassifolia, top-kill and tree death were greatest in the smaller-diameter individuals. Also, the probability of top-kill was much greater than the probability of mortality; however, this difference diminished at diameters greater than 16 cm. Similarly, with A. xalapensis, there was an inverse relationship between diameter and probability of tree death.
Maternal affective input in mother–child interaction
Authors: Jing-Schmidt Zhuo
Published: July 2012

Contrastive analysis of Chinese and American maternal affective speech acts revealed significant differences in the quantity of child-directed positive and negative speech acts. There were also important qualitative differences in specific types of maternal affective input. Results are consistent with available knowledge of cross-cultural differences in parenting approaches, and have implications for cross-cultural emotion and pragmatic development. Differential cultural values were addressed to account for the observed linguistic behaviors.
The impact of age and exposure on bilingual development in international adoptees and family migrants
Authors: Schmid Monika S.
Published: July 2012

This paper addresses the long-term effects of being exposed to a language early in life for a limited period of time, as is the case in international adoptees. Recent findings are divided as to whether such a situation will lead to sequential monolingualism or whether speakers do remain bilingual to some extent, although they cannot readily access their vestigial first language (L1) knowledge. Similarly, it has been debated whether a complete switch in language use will provide a qualitative advantage for second language (L2) learning. The present paper investigates L1 and L2 proficiency among German Jews who escaped from Germany at ages 9-15 years either on a Kindertransport, to be placed in English speaking foster families, or in the company of their family. The results suggest that age plays a more important role than context in both L1 retention and L2 development.
Evolution of the turtle bauplan: the topological relationship of the scapula relative to the ribcage
Authors: Lyson Tyler R. , Joyce Walter G.
Published: July 2012

The turtle shell and the relationship of the shoulder girdle inside or ‘deep’ to the ribcage have puzzled neontologists and developmental biologists for more than a century. Recent developmental and fossil data indicate that the shoulder girdle indeed lies inside the shell, but anterior to the ribcage. Developmental biologists compare this orientation to that found in the model organisms mice and chickens, whose scapula lies laterally on top of the ribcage. We analyse the topological relationship of the shoulder girdle relative to the ribcage within a broader phylogenetic context and determine that the condition found in turtles is also found in amphibians, monotreme mammals and lepidosaurs. A vertical scapula anterior to the thoracic ribcage is therefore inferred to be the basal amniote condition and indicates that the condition found in therian mammals and archosaurs (which includes both developmental model organisms: chickens and mice) is derived and not appropriate for studying the developmental origin of the turtle shell. Instead, among amniotes, either monotreme mammals or lepidosaurs should be used.
Migratory constraints on yolk precursors limit yolk androgen deposition and underlie a brood reduction strategy in rockhopper penguins
Authors: Crossin Glenn T. , Poisbleau Maud , Demongin Laurent , Chastel Olivier , Williams Tony D. , Eens Marcel , Quillfeldt Petra
Published: July 2012

Hormonally mediated maternal effects link maternal phenotype and environmental conditions to offspring phenotype. The production of lipid-rich maternal yolk precursors may provide a mechanism by which lipophilic steroid hormones can be transported to developing yolks, thus predicting a positive correlation between yolk precursors in mothers and androgen levels in eggs. Using rockhopper penguins (
Eudyptes chrysocome
), which produce a two-egg clutch characterized by extreme egg-size dimorphism, reversed hatching asynchrony and brood-reduction, we examined correlations between circulating concentrations of the primary yolk-precursor vitellogenin (VTG) and levels of yolk androgens. Previous work in
Eudyptes
penguins has shown that egg-size dimorphism is the product of migratory constraints on yolk precursor production. We predicted that if yolk precursors are constrained, androgen transport to developing yolks would be similarly constrained. We reveal positive linear relationships between maternal VTG and androgens in small A-eggs but not larger B-eggs, which is consistent with a migratory constraint operating on the A-egg. Results suggest that intra-clutch variation in total yolk androgen levels depends on the production and uptake of yolk precursors. The brood reduction strategy common to
Eudyptes
might thus be best described as the result of a migratory constraint.
Song in the cold is ‘hot’: memory of and preference for sexual signals perceived under thermal challenge
Authors: Beaulieu Michaël , Sockman Keith W.
Published: July 2012

The environmental conditions under which signals are perceived can affect receiver responses. Many songbird populations produce a song chorus at dawn, when, in cold habitats, they would experience thermal challenge. We recorded temperature and the song activity of Lincoln's sparrows (Melospiza lincolnii) on a high-elevation meadow, and determined that song behaviour is concentrated around the coldest time of the day, at dawn. We hypothesized that this is because male song in the cold is more attractive to females than song in the warm. To test this, we exposed laboratory-housed Lincoln's sparrow females to songs at 1°C and 16°C, which they naturally experience in the wild. Females spent 40 per cent more time close to the speaker during playback at 1°C than at 16°C. When tested at 16°C 1–2 days later, females biased their movement towards the speaker playing songs previously heard at 1°C over 16°C. Thus, female Lincoln's sparrows remembered and affiliated with songs they heard under thermal challenge, indicating that the thermal environment can affect the attractiveness of a sexual signal.
The energetic cost of mating in a promiscuous cephalopod
Authors: Franklin Amanda Michelle , Squires Zoe Elizabeth , Stuart-Fox Devi
Published: July 2012

Costs that individuals incur through mating can play an important role in understanding the evolution of life histories and senescence, particularly in promiscuous species. Copulation costs, ranging from energy expenditure to reduced longevity, are widely studied in insects but have received substantially less attention in other taxa. One cost of mating, the energetic cost, is poorly studied across all taxa despite its potential importance for the many species where copulation is physically demanding and/or frequent. Here, we investigated the energetic cost of mating in both male and female dumpling squid (Euprymna tasmanica). In this species, copulation can last up to 3 h and requires that the male physically restrains the female. We report that the act of copulation halves the swimming endurance of both sexes, and that they take up to 30 min to recover. Such a reduction in post-copulatory performance may have important implications for predator avoidance, foraging ability and energy allocation. Therefore, quantifying this cost is essential to understand the evolution of reproductive strategies and behaviours such as female receptivity and male and female mating frequency.
Nano-sized manganese oxides as biomimetic catalysts for water oxidation in artificial photosynthesis: a review
Authors: Najafpour Mohammad Mahdi , Rahimi Fahimeh , Aro Eva-Mari , Lee Choon-Hwan , Allakhverdiev Suleyman I.
Published: July 2012

There has been a tremendous surge in research on the synthesis of various metal compounds aimed at simulating the water-oxidizing complex (WOC) of photosystem II (PSII). This is crucial because the water oxidation half reaction is overwhelmingly rate-limiting and needs high over-voltage (approx. 1 V), which results in low conversion efficiencies when working at current densities required for hydrogen production via water splitting. Particular attention has been given to the manganese compounds not only because manganese has been used by nature to oxidize water but also because manganese is cheap and environmentally friendly. The manganese–calcium cluster in PSII has a dimension of about approximately 0.5 nm. Thus, nano-sized manganese compounds might be good structural and functional models for the cluster. As in the nanometre-size of the synthetic models, most of the active sites are at the surface, these compounds could be more efficient catalysts than micrometre (or bigger) particles. In this paper, we focus on nano-sized manganese oxides as functional and structural models of the WOC of PSII for hydrogen production via water splitting and review nano-sized manganese oxides used in water oxidation by some research groups.
Enzyme activity demonstrates multiple pathways of innate immunity in Indo-Pacific anthozoans
Authors: Palmer C. V. , Bythell J. C. , Willis B. L.
Published: July 2012

Coral reefs are threatened by increasing levels of coral disease and the functional loss of obligate algal symbionts (bleaching). Levels of immunity relate directly to susceptibility to these threats; however, our understanding of fundamental aspects of coral immunology is lacking. We show that three melanin-synthesis pathway components (mono-phenoloxidase,
ortho
-diphenoloxidase (tyrosinase-type pathway) and
para
-diphenoloxidase (laccase-type pathway)) are present in both their active (phenoloxidase, PO) and inactive (prophenoloxidase, PPO) forms across a diverse range of 22 species of healthy Indo-Pacific anthozoans. We also demonstrate transglutaminase activity of the coagulation cascade for, to our knowledge, the first time in a coral. Melanin-synthesis enzyme activities varied among taxa, although they were generally lowest in the coral family Acroporidae and highest in the Poritidae and Oculinidae. Inactive tyrosinase-type activity (PPO) and active laccase-type activity (PO) correlate with taxonomic patterns in disease resistance, whereas the converse pattern in activity levels correlates with bleaching resistance. Overall, we demonstrate the presence of several melanin-synthesis pathways in Indo-Pacific corals, co-regulation among some pathway components, and highlight their potential roles in coral health.
Evolution of leaf form correlates with tropical–temperate transitions in
Viburnum
(Adoxaceae)
Authors: Schmerler Samuel B. , Clement Wendy L. , Beaulieu Jeremy M. , Chatelet David S. , Sack Lawren , Donoghue Michael J. , Edwards Erika J.
Published: July 2012

Strong latitudinal patterns in leaf form are well documented in floristic comparisons and palaeobotanical studies. However, there is little agreement about their functional significance; in fact, it is still unknown to what degree these patterns were generated by repeated evolutionary adaptation. We analysed leaf form in the woody angiosperm clade
Viburnum
(Adoxaceae) and document evolutionarily correlated shifts in leafing habit, leaf margin morphology, leaf shape and climate. Multiple independent shifts between tropical and temperate forest habitats have repeatedly been accompanied by a change between evergreen, elliptical leaves with entire margins and deciduous, more rounded leaves with toothed or lobed margins. These consistent shifts in
Viburnum
support repeated evolutionary adaptation as a major determinant of the global correlation between leaf form and mean annual temperature. Our results provide a new theoretical grounding for the inference of past climates using fossil leaf assemblages.
A new polymorph of physcion
Authors: Hopf Henning , Jones Peter G. , Goclik Eva , Aust Pauline , Rödiger Johanna
Published: July 2012

The structure of the title compound, 7-methoxy-2-methyl-4,5-dihydroxyanthracene-9,10-dione, C16H12O5, was originally reported by Ulickýet al.[Acta Cryst.(1991). C47, 1879–1881] in the space groupP212121[polymorph (Io)]. The new polymorph, (Im), crystallizes in the space groupP21/c. The molecular structures are closely similar, with both –OH groups forming intramolecular hydrogen bonds to one of the neighbouring quinone O atoms, thus slightly lengthening this C=O bond; the pattern of C—C bond lengths in the ring system is consistent with some contribution from a resonance form with a negative charge at the hydrogen-bonded quinone O atom and an aromatic region around its neighbouring C atoms. The packing of (Im) is simpler than the extensively crosslinked pattern of (Io), with molecular tapes connected by classical (but three-centre) and `weak' hydrogen bonds, parallel to [20\overline{1}].
A one-dimensional heterometallic coordination polymer with a three-dimensional supramolecular framework: poly[μ2-aqua-diaqua(2,2′-bipyridyl)(μ5-2-sulfonatobutanedioato)copper(II)sodium(I)]
Authors: Fu Jiang-Hong , Wang Yu-Ling , Chen Ying , Hu Chang-Hui , Tang Li
Published: July 2012

The title compound, [CuNa(C4H3O7S)(C10H8N2)(H2O)3]n, consists of one CuIIcation, one NaIcation, one 2-sulfonatobutanedioate trianion (SSC3−), one 2,2′-bipyridyl (bpy) ligand and three coordinated water molecules as the building unit. The coordination of the CuIIcation is composed of two pyridyl N atoms, one water O atom and two carboxylate O atoms in a distorted square-pyramidal coordination geometry with an axial elongation. The NaIcation is six-coordinated by three water molecules and three carboxylate O atoms from three SSC3−ligands in a distorted octahedral geometry. Two SSC3−ligands link two CuIIcations to form a Cu2(SSC)2(bpy)2macrocyclic unit lying across an inversion centre, which is further linked by NaIcationsviaNa—O bonds to give a one-dimensional chain. Interchain hydrogen bonds link these chains to form a two-dimensional layer, which is further extended into a three-dimensional supramolecular framework through π–π stacking interactions. The thermal stability of the title compound has also been investigated.
Tris[3,6-di-tert-butyl-1-(isoquinolin-1-yl)naphthalen-2-olato-κ2N,O]aluminium(III) toluene sesquisolvate
Authors: Broomfield Lewis M. , Bochmann Manfred , Wright Joseph A.
Published: July 2012

The central AlIIIatom of the title compound, [Al(C27H28NO)3]·1.5C7H8, has octahedral geometry in which the three N atoms are arranged in a meridional fashion. One of the toluene solvent molecules is located on a general position, while the second is disordered around a centre of inversion. The ligand molecule has axial chirality, and two of the three ligands in the complex exhibit the same stereochemistry. The three independent chelate rings exhibit significantly different bite angles at the metal atom, with one [83.72 (8)°] notably smaller than the other two [87.22 (8) and 87.13 (8)°]. Calculation of the solid angle covered by the ligands at the metal atom reveals that coverage is greatest for the ligand group with the shortest Al—O bond distance.
Pseudoaglycone of Spinosyn A
Authors: Chai Hongxin , Liu Mingxing , Zhang Qi , Shi Daxin , Li Jiarong
Published: July 2012

The title compound [systematic name: 9-ethyl-13-hydroxy-14-methyl-2-(3,4,5-trimethoxy-6-methyltetrahydro-2H-pyran-2-yloxy)-3,3a,5b,6,9,10,11,12,13,14,16a,16b-dodecahydro-1H-as-indaceno[3,2-d][1]oxacyclododecine-7,15(2H,5aH)-dione], C33H50O9, was obtained by hydrolysis of Spinosyn A. The fused cyclopentene ring adopts a twisted conformation, while the fused cyclohexene and cyclopentane rings are in envelope conformations with the same C atom at the flaps. In the crystal, molecules are linked by O—H...O and C—H...O hydrogen bonds into a layer parallel to theabplane.
Methyl 4-benzyloxy-7-methoxy-1-methyl-1H-indole-2-carboxylate
Authors: Wang Peng , Xing Hualu , Liu Yang , Xie Wencheng , Zhao Guisen
Published: July 2012

There are two independent molecules in the asymmetric unit of the title compound, C19H19NO4. The indole unit in each molecule is essentially planar, with mean deviations of 0.017 (1) and 0.013 (1) Å and forms dihedral angles of 50.17 (7) and 26.05 (6)° with the phenyl ring. In the crystal, molecules are linked by weak C–H...π interactions.
catena-Poly[[(1,10-phenanthroline)cobalt]-μ-2,4′-oxydibenzoato]
Authors: Guo Hai-Kang , Fu Feng , Tang Long , Hou Xiang-Yang , Cao Jia
Published: July 2012

In the title compound, [Co(C14H8O5)(C12H8N2)]n, the CoIIatom is six-coordinated in a distorted octahedral coordination geometry by four O atoms from two chelating carboxylate groups from different 2,4′-oxydibenzoate anions and by two N atoms from a 1,10-phenanthroline (phen) ligand. The two benzene rings of the 2,4′-oxydibenzoate ligand form a dihedral angle of 77.14 (16)°. Adjacent CoIIatoms are bridged by 2,4′-oxydibenzoate anions to form a helical chain that propagates along theb-axis direction. Neighboring chains are further assembled by intermolecular π–π stacking interactions between inversion-related phen ligands [centroid-to-centroid distance = 4.0869 (8) Å] to form a two-dimensional supramolecular architecture.
(Acetylacetonato-κ2O,O′)bis{5-fluoro-2-[3-(4-fluorophenyl)pyrazin-2-yl]phenyl-κ2N1,C1}iridium(III)
Authors: Ge Guo-Ping , Li Chun-Yan
Published: July 2012

In the title complex, [Ir(C16H9F2N2)2(C5H7O2)], the IrIIIatom, lying on a twofold rotation axis, is hexacoordinated in a distorted octahedral geometry by twoC,N-bidentate 5-fluoro-2-[3-(4-fluorophenyl)pyrazin-2-yl]phenyl ligands and oneO,O′-bidentate acetylacetonate ligand. The dihedral angles between the benzene rings and the pyrazine ring are 14.66 (8) and 49.76 (12)°.
N-(1,3-Thiazol-2-yl)-2-(2,4,6-trimethylphenyl)acetamide
Authors: Fun Hoong-Kun , Quah Ching Kheng , Nayak Prakash S. , Narayana B. , Sarojini B. K.
Published: July 2012

In the title compound, C14H16N2OS, the thiazole ring is essentially planar (r.m.s. deviation = 0.005 Å) and it forms a dihedral angle of 75.21 (8)° with the benzene ring. In the crystal, molecules are linked into inversion dimers by pairs of N—H...N hydrogen bonds to generateR22(8) loops.
(2S,4R)-4-Fluoropyrrolidinium-2-carboxylate
Authors: Hobart Jr David B. , Merola Joseph S.
Published: July 2012

The crystal structure of the title compound, C5H8FNO2, at 100 K, displays intermolecular N—H...O hydrogen bonding between the ammonium and carboxylate groups as a result of its zwitterionic nature in the solid state. The five-membered ring adopts an envelope conformation with the C atom at the 3-position as the flap. The compound is of interest with respect to the synthesis and structural properties of synthetic collagens. The absolute structure was determined by comparison with the commercially available material.
catena-Poly[[tetraaquacopper(II)]-μ-pyrazine-2-carboxamide-κ3N4:N1,O-[bis(sulfato-κO)copper(II)]-μ-pyrazine-2-carboxamide-κ3N1,O:N4]
Authors: Shirvan Sadif A. , Haydari Dezfuli Sara
Published: July 2012

In the crystal of the title polymeric compound, [Cu2(SO4)2(C5H5N3O)2(H2O)4]n, two independent CuIIatoms are located on individual inversion centers. One CuIIatom is coordinated by four water molecules and two pyrazine-2-carboxamide ligands in a distorted O4N2octahedral geometry; the other isN,O-chelated by two pyrazine-2-carboxamide ligands and further coordinated by two sulfate anions in a distorted O4N2octahedral geometry. The pyrazine-2-carboxamide ligands bridge the CuIIatoms to form a polymeric chain running along [110]. The crystal structure features N—H...O, O—H...O and weak C—H...O hydrogen bonds.
4-[(4-Chlorophenyl)(phenyl)methyl]piperazin-1-ium picrate monohydrate
Authors: Song Yanxi , Chidan Kumar C. S. , Chandraju S. , Naveen S. , Li Hongqi
Published: July 2012

The asymmetric unit of the title compound, C17H20ClN2+·C6H2N3O7−·H2O, contains a piperazin-1-ium cation, a picrate anion and one solvent water molecule. The piperazene ring is protonated at one N atom and adopts a highly distorted chair conformation with the chloropheny(phenyl)methyl substituent on the second N atom in an equatorial position. The crystal structure is stabilized by O—H...O, N—H...O and C—H...O hydrogen bonds.
{4,4′,6,6′-Tetraiodo-2,2′-[propane-1,3-diylbis(nitrilomethanylylidene)]diphenolato-κ4O,N,N′,O′}nickel(II)
Authors: Kargar Hadi , Kia Reza , Adabi Ardakani Amir , Tahir Muhammad Nawaz
Published: July 2012

The asymmetric unit of the title compound, [Ni(C17H12I4N2O2)], comprises half of a Schiff base complex. The NiIIand central C atom of the propyl chain are located on a twofold rotation axis. The geometry around the NiIIatom is square planar, supported by the N2O2donor atoms of the coordinated ligand. In the crystal, there are no significant intermolecular interactions present. The crystal studied was a non-merohedral twin with a refined twin component ratio of 0.944 (1):0.056 (1).
2-[(Z)-(3-{[(Z)-2-Hydroxy-3,5-diiodobenzylidene]amino}propylimino)methyl]-4,6-diiodophenol
Authors: Kargar Hadi , Kia Reza , Adabi Ardakani Amir , Tahir Muhammad Nawaz
Published: July 2012

In the title compound, C17H14I4N2O2, there are two intramolecular O—H...N hydrogen bonds, which makeS(6) ring motifs. In the crystal, there are no significant intermolecular interactions present.
A general principle for light reflecting from a uniformly moving mirror: A relativistic treatment
Authors: Galli J. Ronald , Amiri Farhang
Published: July 2012

We investigate the reflection of light from a mirror moving at relativistic speeds and introduce a general principle to determine the relationship between the incident and reflected angles. This principle states that the momentum change of each photon is perpendicular to the surface of the mirror. We carry out sample calculations for various geometries.
Noise prediction of loader by using BEM and SEA
Authors: Choi Jae-Woong , Lee Hee-Joon , Kang Shin-Il , Kang Jong-Min
Published: July 2012

Though the international regulations about the noise level of earth-moving machinery becomes more and more strict, it is not known that an analytical tool could be applied to predicting radiation noise. In this study, a systematic procedure is introduced in terms of the noise source modeling, application of the existing analytical tools, and verification. This research selects BEM and SEA by considering the modal density, and does the noise sources modeled in appropriate forms for each method. A half-scale model of real loader and a simple source are used to verify the approach. Comparisons of the simulated and experimental results show good agreements in both the simple and real loader cases. These results suggest that the approach should be applied to the investigation of ways for an effective noise reduction by using a simulated noise prediction.
Technique for exploiting the temporal order in acoustic fluctuations to enhance signal processor performance
Authors: Wagstaff Ronald A. , Mobbs Jackson A.
Published: July 2012

There are scenarios of interest in which the signals have smaller fluctuation amplitudes than the clutter and noise. When this is the case, it has been shown [R. A. Wagstaff, J. Acoust. Soc. Am. 100, 2853(A) (1996)] that extraordinary gains can be achieved by signal processors that are designed to discriminate according to fluctuation amplitude. It is also possible to achieve similar gains from processors that are designed to discriminate based on the temporal order dependence of the fluctuations. Since this temporal order-dependent processor is unrelated to other order-independent fluctuation-based processors such as WISPR and AWSUM, the gains can be increased by combining the methods. This order-dependent fluctuation-based signal processor will be described, and the gains including signal-to-noise ratio enhancement, clutter reduction, and unalerted-automatic detection will be discussed. The results will be illustrated using measured data. In addition, results from combining the two different fluctuation-based processing methods, order dependent and order independent, to achieve additional gain will also be presented. [Work supported by ONR and NRL.]
The influence of aperture shape on Rayleigh conductivity for one-sided grazing flow
Authors: Grace Sheryl M. , Horan Kelly P.
Published: July 2012

It is well known that flow past wall apertures and wall cavities can generate sound. This resulting sound is most often undesirable. For underwater applications, such as flow past cavities in a ship’s hull, the constancy of the phenomenon warrants passive control to reduce the acoustic radiation. In this research aperture shape is studied as a passive control mechanism. The Rayleigh conductivity for apertures of different shapes in the presence of one-sided grazing mean flow subject to an externally applied pressure perturbation is investigated numerically. Physically, the external pressure perturbation can result from an external sound source or large scale structural vibration. Because the linear stability of the shear flow over the aperture is governed by the properties of the Rayleigh conductivity, studies of the Rayleigh conductivity as a function of Strouhal number determine the frequency and flow speeds which correspond to self-sustaining oscillations of the flow and acoustic radiation. It is shown that all symmetric apertures with smooth leading edges behave similarly. For example, circular, square, triangular, and cross-shaped apertures all show similar conductivity patterns. However, results show that the conductivity can be altered by making either the aperture asymmetric or the leading edge of the aperture jagged.
Stochastic ray theory, chaos, and predictability
Authors: Brown Michael G.
Published: July 2012

The motion of sound ray trajectories in deep ocean environments is considered, assuming that the internal wave-induced sound speed fluctuations can be treated stochastically. The ray equations then constitute a system of stochastic differential (Langevin) equations. Equivalently, the expected ray density—an approximation to the average acoustic intensity—can be shown to satisfy a Fokker–Planck equation. The Fokker–Planck equation can be interpreted in fluid mechanical terms as an advection-diffusion equation. This observation leads to the notion of a diffusion-limited (as opposed to diffraction-limited) estimate of the chaos-induced ‘‘predictability horizon.’’ [Work supported by ONR.]
Audiologic findings in a cohort of adults with diabetes
Authors: Blood Ingrid M. , Cavanagh Peter R. , Tufts Jennifer , Boddorf Dana J.
Published: July 2012

The hearing status in 45 adults with diabetes (mean age = 59.87 years, s.d. = 9.83) and an age-matched control group of individuals was examined. The average duration of diabetes was 17.02 years (s.d. 9.66). Although hearing loss has been previously documented in patients with diabetes, the relationship between hearing impairment and diabetes is unclear. Etiology of hearing loss, whether cochlear or retrocochlear, has also been debated in the literature. Audiometric thresholds, word recognition scores in quiet and in competing noise of +6 dB signal-to-noise ratio, and transiently evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE) were obtained. Comparisons in audiometric results were made between diabetics with and without complications (30 with and 15 without neuropathy). Results revealed considerable variability in hearing sensitivity, audiometric configuration, and speech recognition in the presence of noise. Mean auditory thresholds and TEOAE and DPOAE values were calculated. Otoacoustic emissions were reduced in amplitude or absent in subjects with sensorineural hearing loss regardless of diabetic status. Relations between measures and clinical implications will be discussed. [Work supported by NIH.]
Average acoustical characteristics of ten atrium spaces
Authors: Bradley J. S. , Oh Y. K.
Published: July 2012

Extensive acoustical measurements were made in ten different atrium spaces varying in volume from 3 300 to 45 000 m3. Impulse responses were measured at between 18 and 71 combinations of source and receiver position in each atrium depending on the size of the atrium. The computer-based measurement system (RAMSoft-3) used a maximum length sequence signal and a fast Hadamard transform procedure to obtain 5-s-long impulse responses. Octave band values of decay times, sound levels, and energy ratios were calculated for each impulse response. The average values of each quantity in each atrium were used to characterize typical acoustical characteristics of untreated atria. These allow rough estimates of the acoustical conditions in other atria as a function of the volume of the spaces.
Analysis of pulse propagation in range-independent and range-dependent sound channels with double duct
Authors: Sidorovskaia Natalia A. , Werby Michael F. , DeFerrari Harry , Williams Neil J.
Published: July 2012

An acoustic dataset collected during the 1983 Florida Straits Experiment [H. A. DeFerrari and H. B. Nguyen, J. Acoust. Soc. Am. 79, 299 (1986)] is modeled using the normal-mode acoustic model SWAMP (shallow water acoustic modal propagation by M. F. Werby and N. A. Sidorovskaia) and parabolic acoustic model RAM (range-dependent acoustic model by M. Collins). The goal of the computer simulation is to get systematic studies of the influence of range-independent and range-dependent environments on the received pulse structure observed in the experiment. In the experiment the pulse, with central frequency 460 Hz, was sent through three different shallow-water acoustic channels with surface and bottom ducts. It was found that the surface duct generated an important temporally stable effect for the range-independent environment. At a range 42 km, six surface trapped precursors were observed. The range-dependent propagation channel implied that the energy transfers between modes made the effect less pronounced when only three weak precursors could be seen. The obtained systematic studies can be important in constructing inverse tomography techniques, in predicting sea-bed characteristics, and in better understanding the influence of the ocean ducts on sound propagation.
Statistical characteristics of the acoustic emission signals
Authors: Tran Dat H. , Krasilnikov Alexsandr J.
Published: July 2012

The typical block of signal processing in the instrument of diagnostic and construction damage prediction by the acoustic emission (AE) method was proposed, which consists of an inertial detector, comparator, and counter. The correlation between the registered parameters (number of impulses, activity, average level, density of amplitude distribution) and the initial AE flux on the input of the signal was described by the method of linear random processes. On the basis of phenomenon modeling, it was shown that, in an ideal condition, the discrete AE signal fits the gamma distribution. The dynamical approach to the model also attempts to extend it in relation to the three-dimensional coordinates. The deviations of the relation between the registered and proper AE meanings and the method of the results correction are shown.
A forward-scan sonar system for small unmanned submersibles
Authors: Cuschieri Joe , LeBlanc Lester
Published: July 2012

Over the past 3 years, work has been devoted to the development of a forward-looking sonar system that can be used in small unmanned submersibles. One of the sonar systems developed, a forward scan (FS) sonar, generates side-scan-type images with the exception that multiple scan lines (120 lines in a ±60-deg forward-looking sector) are simultaneously formed, using digital processing of the signals received by the 64 elements of the receiver hydrophone array. The system operates at 230 kHz with a 10% bandwidth using a frequency chirp. The signals received by each element of the receiver hydrophone are sampled and digitized. Since the signals only have 10% bandwidth, the digital data are filtered and decimated to reduce the volume of data processed. Test tank and at-sea sonar images have been obtained using the FS sonar at the rate of one image per second using two skybolt quad i860 processors. The target is to generate four images per second. [Work sponsored by ONR.]
Coupling of land-based signals into the nearshore underwater acoustic field
Authors: D’Spain Gerald L. , Berger Lewis P. , Dorman LeRoy M. , Hodgkiss William S. , Kuperman William A.
Published: July 2012

Small, controlled land detonations on and near the beach recorded by land geophones and by offshore seismoacoustic sensors are used to characterize the coupling between land seismic and underwater acoustic fields. These data were collected in the Marine Physical Laboratory’s Adaptive Beach Monitoring program. The predominant arrival on land is an elastic surface wave. Although an ocean bottom interface wave can be seen clearly in seismoacoustic recordings just outside the surf zone, it attenuates to nearly background noise levels by the time it reaches a bottom hydrophone array 1.5 km offshore in 12-m water. Travel-time and frequency/wave-number analyses indicate that the hydrophone array’s received energy is composed mostly of dispersive body waves propagating as the lowest water-borne mode, with frequency-dependent phase and group velocities around 2.0 and 1.8 km/s, respectively. The frequency at which this lowest mode cuts off is the corner frequency of the high-pass filter representing the propagation from land to the underwater acoustic field. These results and numerical modeling, guided by insights obtained from classic work on acoustic propagation in a fluid wedge, are used to explain offshore underwater recordings of land vehicle activity. [Work supported by ONR, Code 32.]
Relation of acoustical parameters with and without audiences in concert halls and a simple method for simulating the occupied state
Authors: Hidaka Takayuki , Beranek Leo L. , Nishihara Noriko
Published: July 2012

Six acoustical parameters, RT, EDT, C80, D, G, and IACCE3, were measured with and without audiences at six concert and opera halls. The range in volume was 3576 to 15 300 m3. The upholstering of the chairs ranged from light to heavy. Comparisons were made of these parameters before and after addition of the audience. The conclusions are: (1) Predictions of the occupied reverberation times were found inaccurate when the measured unoccupied values were adjusted by using unoccupied versus occupied data for the chairs obtained in a reverberation chamber. If diffuse sound conditions are assumed, it would be possible to predict EDT, C80, D, and G from the occupied RT values whether measured or calculated as above. Such predictions are also inaccurate. (2) Plots of the six parameters, i.e., unoccupied versus occupied values, are nearly straight lines with correlations generally in excess of 0.9. These high correlations permit the use of empirical equations to predict these parameters for occupied halls from measurements made in unoccupied halls. (3) It was also found that IACCE3 is almost the same whether measured with or without audience. This supports a previous report that IACCE3, for unoccupied halls, is of importance in assessing their subjective quality when occupied [Hidaka et al., J. Acoust. Soc. Am. 989–1007 (1995)]. This paper also reports on the successful use of a cloth covering over unoccupied seats to simulate occupied conditions.
Objective and subjective measurement of 15 opera houses in Europe and the USA
Authors: Hidaka Takayuki , Beranek Leo L.
Published: July 2012

Acoustical measurements were executed at 15 major opera houses in eight countries under unoccupied conditions. The objective parameters determined are RT, EDT, C80, D, G, IACCE3, and IACCA, which are common attributes needed for concert hall evaluation. The measured unoccupied RT’s range from 1.26 to 2.15s and occupied RTs, usually predicted using the empirical equations of the preceding presentation, range from 1.19 to 1.74 s. The range of the other six parameters are also examined. In particular, [1-IACCE3] has a range from 0.39 to 0.72, which is similar to that for concert halls [Hidaka et al., J. Acoust. Soc. Am. 998–1007 (1995)]. Questionnaires have been returned from about 20 opera conductors which enable the authors to present subjective evaluations of the halls. Finally, the subjective evaluations are compared with the objective data.
Vowel and consonant durations as cues for quantity in Icelandic
Authors: Pind Jörgen
Published: July 2012

Icelandic distinguishes short and long consonants and vowels in stressed syllables. Phonologically, these show complementary quantity in that a short vowel is followed by a long consonant and vice versa. Perceptual experiments have shown that the ratio of vowel to consonant duration is the major cue for quantity, although the vowel spectrum can override the relational cue in those cases where there is a marked difference in the spectral character of the long and short vowels [J. Pind, Scand. J. Psychol. 37, 121–131 (1996)]. Measurements will be reported of vowel and consonant durations in stressed syllables in words spoken repeatedly in sentence frames and in longer connected texts. The utterances were read at different speaking rates. Two questions are of major interest in this study: (1) To what extent do vowel and consonant durations in different environments support a relational cue for quantity? and (2) Is the durational cue weaker in those cases where the spectra of short and long vowels provide another cue for quantity? [Work supported by the Icelandic Science Foundation and University of Iceland.]
Chronic C-Type Natriuretic Peptide Infusion Attenuates Angiotensin II-Induced Myocardial Superoxide Production and Cardiac Remodeling
Authors: Izumiya Yasuhiro , Araki Satoshi , Usuku Hiroki , Rokutanda Taku , Hanatani Shinsuke , Ogawa Hisao
Published: July 2012

Myocardial oxidative stress and inflammation are key mechanisms in cardiovascular remodeling. C-type natriuretic peptide (CNP) is an endothelium-derived cardioprotective factor, although its effect on cardiac superoxide generation has not been investigated in vivo. This study tested the hypothesis that suppression of superoxide production contributes to the cardioprotective action of CNP. Angiotensin II (Ang II) or saline was continuously infused subcutaneously into mice using an osmotic minipump. Simultaneously with the initiation of Ang II treatment, mice were infused with CNP (0.05 μg/kg/min) or vehicle for 2 weeks. The heart weight to tibial length ratio was significantly increased by Ang II in vehicle-treated mice. Treatment with CNP decreased Ang II-induced cardiac hypertrophy without affecting systolic blood pressure. Echocardiography showed that CNP attenuated Ang II-induced increase in wall thickness, left ventricular dilatation, and decrease in fractional shortening. CNP reduced Ang II-induced increases in cardiomyocyte size and interstitial fibrosis and suppressed hypertrophic- and fibrosis-related gene expression. Finally, CNP decreased Ang II-induced cardiac superoxide production. These changes were accompanied by suppression of NOX4 gene expression. Our data indicate that treatment with CNP attenuated Ang II-induced cardiac hypertrophy, fibrosis, and contractile dysfunction which were accompanied by reduced cardiac superoxide production.
Photobiomodulation Process
Authors: Xu Yang-Yi , Liu Timon Cheng-Yi , Cheng Lei
Published: July 2012

Photobiomodulation (PBM) is a modulation of laser irradiation or monochromatic light (LI) on biosystems. There is little research on PBM dynamics although its phenomena and mechanism have been widely studied. The PBM was discussed from dynamic viewpoint in this paper. It was found that the primary process of cellular PBM might be the key process of cellular PBM so that the transition rate of cellular molecules can be extended to discuss the dose relationship of PBM. There may be a dose zone in which low intensity LI (LIL at different doses) has biological effects similar to each other, so that biological information model of PBM might hold. LIL may self-adaptively modulate a chronic stress until it becomes successful.
Peroxisome Proliferator Activated Receptor-αAgonist Slows the Progression of Hypertension, Attenuates Plasma Interleukin-6 Levels and Renal Inflammatory Markers in Angiotensin II Infused Mice
Authors: Wilson Justin L. , Duan Rong , El-Marakby Ahmed , Alhashim Abdulmohsin , Lee Dexter L.
Published: July 2012

The anti-inflammatory properties of PPAR-αplays an important role in attenuating hypertension. The current study determines the anti-hypertensive and anti-inflammatory role of PPAR-αagonist during a slow-pressor dose of Ang II (400 ng/kg/min). Ten to twelve week old male PPAR-αKO mice and their WT controls were implanted with telemetry devices and infused with Ang II for 12 days. On day 12 of Ang II infusion, MAP was elevated in PPAR-αKO mice compared to WT (161±4 mmHg versus145±4 mmHg) and fenofibrate (145 mg/kg/day) reduced MAP in WT + Ang II mice (134±7 mmHg). Plasma IL-6 levels were higher in PPAR-αKO mice on day 12 of Ang II infusion (30±4versus8±2 pg/mL) and fenofibrate reduced plasma IL-6 in Ang II-treated WT mice (10±3 pg/mL). Fenofibrate increased renal expression of CYP4A, restored renal CYP2J expression, reduced the elevation in renal ICAM-1, MCP-1 and COX-2 in WT + Ang II mice. Our results demonstrate that activation of PPAR-αattenuates Ang II-induced hypertension through up-regulation of CYP4A and CYP2J and an attenuation of inflammatory markers such as plasma IL-6, renal MCP-1, renal expression of ICAM-1 and COX-2.
The Effects of Mixing, Reaction Rates, and Stoichiometry on Yield for Mixing Sensitive Reactions—Part I: Model Development
Authors: Shah Syed Imran A. , Kostiuk Larry W. , Kresta Suzanne M.
Published: July 2012

There are two classes of mixing sensitive reactions: competitive-consecutive and competitive-parallel. The yield of desired product from these coupled reactions depends on how fast the reactants are brought together. Recent experimental results have suggested that the mixing effect may depend strongly on the stoichiometry of the reactions. To investigate this, a 1D, dimensionless, reaction-diffusion model at the micromixing scale was developed. Assuming constant mass concentration and mass diffusivities, systems of PDE's were derived on a mass fraction basis for both types of reactions. Two dimensionless reaction rate ratios and a single general Damköhler number emerged from the analysis. The resulting dimensionless equations were used to investigate the effects of mixing, reaction rate ratio, and reaction stoichiometry. As expected, decreasing either the striation thickness or the dimensionless rate ratio maximizes yield, the reaction stoichiometry has a considerable effect on yield, and all three variables interact strongly.
Age Differences among Female Sex Workers in the Philippines: Sexual Risk Negotiations and Perceived Manager Advice
Authors: Urada Lianne A. , Malow Robert M. , Santos Nina C. , Morisky Donald E.
Published: July 2012

Consistent condom use among high risk groups such as female sex workers (FSWs) remains low. Adolescent female sex workers are especially at higher risk for HIV/STI infections. However, few published studies have compared the sexual risk negotiations among adolescent, emerging adult, and older age groups or the extent a manager’s advice about condom use is associated with an FSW’s age. Of 1,388 female bar/spa workers surveyed in the southern Philippines, 791 FSW who traded sex in the past 6 months were included in multivariable logistic regression models. The oldest FSWs (aged 36–48) compared to adolescent FSWs (aged 14–17) were 3.3 times more likely to negotiate condoms when clients refused condom use. However, adolescent FSWs received more advice from their managers to convince clients to use condoms or else to refuse sex, compared to older FSWs. Both adolescent and the oldest FSWs had elevated sexually transmitted infections (STIs) and inconsistent condom use compared to other groups. Having a condom rule at the establishment was positively associated with condom negotiation. Factors such as age, the advice managers give to their workers, and the influence of a condom use rule at the establishment need to be considered when delivering HIV/STI prevention interventions.
Global Evaluation of Eph Receptors and Ephrins in Lung Adenocarcinomas Identifies EphA4 as an Inhibitor of Cell Migration and Invasion
Authors: Saintigny Pierre , Peng Shaohua , Zhang Li , Sen Banibrata , Wistuba Ignacio I. , Lippman Scott M. , Girard Luc , Minna John D. , Heymach John V. , Johnson Faye M.
Published: July 2012

The Eph family of receptors is the largest family of receptor tyrosine kinases, but it remains poorly studied in lung cancer. We aimed to systematically explore the human Eph receptors and their ligands, the ephrins, in lung adenocarcinoma. The prognostic impact of Eph receptor and ephrin gene expression was analyzed using 2 independent cohorts of lung adenocarcinoma. Gene expression profiles in lung adenocarcinoma compared with normal adjacent lung were studied in 3 independent cohorts and in cell lines. Gene expression profiles were validated with quantitative polymerase chain reaction (qPCR) and Western blotting in cell lines. Functional studies to assess the role of Eph receptor A4 (EphA4) were carried out in vitro. The biological effects of EphA4 in lung cancer cell lines were assayed following overexpression and knockdown. Of the 11 Eph receptors and 8 ephrins analyzed, only EphA4 and ephrin A1 gene expression were consistently associated with an improved outcome in patients with lung adenocarcinoma. Expression levels of EphA4 by microarray correlated well with expression levels measured by qPCR and Western blotting. EphA4 overexpression reduced cell migration and invasion but did not affect cell cycle, apoptosis, or drug sensitivity. Surprisingly, EphA4 was expressed at higher levels in cancer compared with non-cancer tissues and cell lines. EphA4 gene expression is associated with an improved outcome in patients with resected lung adenocarcinoma, possibly by affecting cancer cell migration and invasion. Mol Cancer Ther; 11(9); 2021–32. ©2012 AACR.