bluuebunny/crossref_metadata_2025 huggingface dataset:
The Machinations of Luck
Authors: Rescher Nicholas
Published: October 2014

Luck is at issue when it is a matter of pure chance that a result of significant positive of negative value ensues for someone. Luck differs from fate, which pivots on an individual's condition, and from fortune, which pivots on an individual's talent and effort. It is by luck that you are rich when you win the lottery, by fortune if your wealth comes from talent and hard work, and by fate if you inherit those millions. On this basis luck lies beyond anyone's rational control. With risk (R) as the probability of failure in a chancy situation and the stake (S) as the difference between a favorable and an unfavorable outcome, luck (L) can be measured as the product of these quantities: L = R × S. The condition of humankind in an uncertain world being as it is, luck cannot be eliminated as a key factor of our existence, be it in cognitive, practical, or ethical regards.
The Modal Account of Luck
Authors: Pritchard Duncan
Published: October 2014

This essay offers a rearticulation and defence of the modal account of luck that the author developed in earlier work (e.g.,Pritchard 2005). In particular, the proposal is situated within a certain methodology, a component of which is paying due attention to the cognitive science literature on luck (and risk) ascriptions. It is shown that with the modal account of luck properly articulated it can adequately deal with some of the problems that have recently been offered against it, and that the view has a number of attractions over competing proposals, such as the lack of control account.
Anscombe and “Hume and Julius Caesar”
Authors: Duran Jane
Published: October 2014

This article analyzes Elizabeth Anscombe's short piece “Hume and Julius Caesar” from the standpoint of traditional foundationalist epistemic criteria, and concludes that while Anscombe may be right about finding a mistake in Hume, she has also failed to fill in her own arguments in the way that her overall aim requires. Special allusion is made to the work of J. L. Austin, especially insofar as that work has to do with reformulating sentences so that they appear to meet foundationalist criteria.
Libertarianism and Free Determined Decisions
Authors: Lemos John
Published: October 2014

Free determined decisions are free decisions that are causally determined by the character of the agent. Robert Kane is a libertarian about free will who believes some of our free decisions are determined in this way. According to Kane, for a determined decision to be free it must proceed from the agent's character and the agent must have shaped that character through previous undetermined free decisions. In recent writings, Mark Balaguer has argued that human beings may well possess libertarian freedom, but he rejects Kane's view that free determined acts must proceed from a character that is constructed from prior undetermined free decisions. This essay explains Balaguer's argument for rejecting the Kanean view and critically responds to it in defense of Kane's position on free determined decisions.
The Potentiality of the Embryo and the Somatic Cell
Authors: McGee Andrew
Published: October 2014

Recent arguments on the ethics of stem cell research have taken a novel approach to the question of the moral status of the embryo. One influential argument focuses on a property that the embryo is said to possess—namely, the property of being an entity with a rational nature or, less controversially, an entity that has the potential to acquire a rational nature—and claims that this property is also possessed by a somatic cell. Since nobody seriously thinks that we have a duty to preserve the countless such cells we wash off our body every day in the shower, the argument is intended as a reductio ad absurdum of the claim that the embryo should be afforded the same moral status as a fully developed human being. This article argues that this argument is not successful and that it consequently plays into the hands of those who oppose embryonic stem cell research. It is therefore better to abandon this argument and focus instead on the different argument that potentiality, as such, is not a sufficient ground for the creation of moral obligations towards the embryo.
Systems biology defines the biological significance of redox‐active proteins during cellulose degradation in an aerobic bacterium
Authors: Gardner Jeffrey G. , Crouch Lucy , Labourel Aurore , Forsberg Zarah , Bukhman Yury V. , Vaaje‐Kolstad Gustav , Gilbert Harry J. , Keating David H.
Published: October 2014

Microbial depolymerization of plant cell walls contributes to global carbon balance and is a critical component of renewable energy. The genomes of lignocellulose degrading microorganisms encode diverse classes of carbohydrate modifying enzymes, although currently there is a paucity of knowledge on the role of these proteins in vivo. We report the comprehensive analysis of the cellulose degradation system in the saprophytic bacterium Cellvibrio japonicus. Gene expression profiling of C. japonicus demonstrated that three of the 12 predicted β‐1,4 endoglucanases (cel5A, cel5B, and cel45A) and the sole predicted cellobiohydrolase (cel6A) showed elevated expression during growth on cellulose. Targeted gene disruptions of all 13 predicted cellulase genes showed that only cel5B and cel6A were required for optimal growth on cellulose. Our analysis also identified three additional genes required for cellulose degradation: lpmo10B encodes a lytic polysaccharide monooxygenase (LPMO), while cbp2D and cbp2E encode proteins containing carbohydrate binding modules and predicted cytochrome domains for electron transfer. CjLPMO10B oxidized cellulose and Cbp2D demonstrated spectral properties consistent with redox function. Collectively, this report provides insight into the biological role of LPMOs and redox proteins in cellulose utilization and suggests that C. japonicus utilizes a combination of hydrolytic and oxidative cleavage mechanisms to degrade cellulose.
Never ending stories: visual diarizing to recreate autobiographical memory of intensive care unit survivors
Authors: Ewens Beverley A , Hendricks Joyce M , Sundin Deb
Published: October 2014

Aim

The aim of this study was to explore the potential use of visual diarizing to enable intensive care unit (ICU) survivors to create their story of recovery.

Background

An ICU experience can have deleterious psychological and physical effects on survivors leading to reductions in quality of life which for some may be of significant duration. Although there has been exploration of many interventions to support recovery in this group, service provision for survivors remains inconsistent and inadequate.

Design and participants

A qualitative interpretive biographical exploration of the ICU experience and recovery phase of ICU survivors using visual diarizing as method. This paper is a component of a larger study and presents an analyses of one participant's visual diary in detail.

Methods

Data collection was twofold. The participant was supplied with visual diary materials at 2 months post‐hospital discharge and depicted his story in words and pictures for a 3‐month period, after which he was interviewed. The interview enabled the participant and researcher to interpret the visual diary and create a biographical account of his ICU stay and recovery journey.

Findings

The analysis of one participant's visual diary yielded a wealth of information about his recovery trajectory articulated through the images he chose to symbolize his story. The participant confirmed feelings of persecution whilst in ICU and was unprepared for the physical and psychological disability which ensued following his discharge from hospital. However, his story was one of hope for the future and a determination that good would come out of his experience. He considered using the visual diary enhanced his recovery.

Conclusions

The participant perceived that visual diarizing enhanced his recovery trajectory by enabling him to recreate his story using visual imagery in a prospective diary.

Relevance to clinical practice

Prospective visual diarizing with ICU survivors may have potential as an aid to recovery.
Putin, Erdogan and Orbán: Band of Brothers?
Authors: SIMONYI ANDRÁS
Published: October 2014

In 1990, right after the Berlin Wall fell, NPQ published our Spring edition, titled “The New World Disorder,” about the nationalistic chaos and up‐in‐theair sensibility of that fraught new historical moment.

Nearly a quarter of a century later, the regime of globalization that had supplanted the Cold War world of blocs is itself coming apart at the seams. Even Henry Kissinger these days says “the world order is crumbling.”

Will this New World Disorder 2.0 revert to a system of conflicting blocs, as during the Cold War, or will we be mature enough to save the interdependence of plural identities that is the foundation of a new global civilization?

In this section our contributors offer their perspectives on what the future holds.
New BRICS Bank a Building Block of Alternative World Order
Authors: KHANNA PARAG
Published: October 2014

In 1990, right after the Berlin Wall fell, NPQ published our Spring edition, titled “The New World Disorder,” about the nationalistic chaos and up‐in‐theair sensibility of that fraught new historical moment.

Nearly a quarter of a century later, the regime of globalization that had supplanted the Cold War world of blocs is itself coming apart at the seams. Even Henry Kissinger these days says “the world order is crumbling.”

Will this New World Disorder 2.0 revert to a system of conflicting blocs, as during the Cold War, or will we be mature enough to save the interdependence of plural identities that is the foundation of a new global civilization?

In this section our contributors offer their perspectives on what the future holds.
Excising stem samples underwater at native tension does not induce xylem cavitation
Authors: VENTURAS MARTIN D. , MACKINNON EVAN D. , JACOBSEN ANNA L. , PRATT R. BRANDON
Published: October 2014

Xylem resistance to water stress‐induced cavitation is an important trait that is associated with drought tolerance of plants. The level of xylem cavitation experienced by a plant is often assessed as the percentage loss in conductivity (PLC) at different water potentials. Such measurements are constructed with samples that are excised underwater at native tensions. However, a recent study concluded that cutting conduits under significant tension induced cavitation, even when samples were held underwater during cutting. This resulted in artificially increased PLC because of what we have termed a ‘tension‐cutting artefact’. We tested the hypothesized tension‐cutting artefact on five species by measuring PLC at native tension compared with after xylem tensions had been relaxed. Our results did not support the tension‐cutting artefact hypothesis, as no differences were observed between native and relaxed samples in four of five species. In a fifth species (Laurus nobilis), differences between native and relaxed samples appear to be due to vessel refilling rather than a tension‐cutting effect. We avoided the tension‐cutting artefact by cutting samples to slightly longer than their measurement length and subsequent trimming of at least 0.5 cm of sample ends prior to measurement.
Stem CO2 efflux in six co‐occurring tree species: underlying factors and ecological implications
Authors: RODRÍGUEZ‐CALCERRADA JESÚS , LÓPEZ ROSANA , SALOMÓN ROBERTO , GORDALIZA GUILLERMO G. , VALBUENA‐CARABAÑA MARÍA , OLEKSYN JACEK , GIL LUIS
Published: October 2014

Stem respiration plays a role in species coexistence and forest dynamics. Here we examined the intra‐ and inter‐specific variability of stem CO2 efflux (E) in dominant and suppressed trees of six deciduous species in a mixed forest stand: Fagus sylvatica L., Quercus petraea [Matt.] Liebl, Quercus pyrenaica Willd., Prunus avium L., Sorbus aucuparia L. and Crataegus monogyna Jacq. We conducted measurements in late autumn. Within species, dominants had higher E per unit stem surface area (Es) mainly because sapwood depth was higher than in suppressed trees. Across species, however, differences in Es corresponded with differences in the proportion of living parenchyma in sapwood and concentration of non‐structural carbohydrates (NSC). Across species, Es was strongly and NSC marginally positively related with an index of drought tolerance, suggesting that slow growth of drought‐tolerant trees is related to higher NSC concentration and Es. We conclude that, during the leafless period, E is indicative of maintenance respiration and is related with some ecological characteristics of the species, such as drought resistance; that sapwood depth is the main factor explaining variability in Es within species; and that the proportion of NSC in the sapwood is the main factor behind variability in Es among species.
Cytochrome P450 oxidoreductase deficiency: Rare congenital disorder leading to skeletal malformations and steroidogenic defects
Authors: Fukami Maki , Ogata Tsutomu
Published: October 2014

Cytochrome P450 oxidoreductase (POR) deficiency (PORD) is a newly characterized disorder. PORD is caused by homozygous or compound heterozygous mutations in POR encoding an electron donor for several microsomal enzymes such as CYP21A2, CYP17A1, CYP19A1, CYP51A1, and CYP26A1‐C1. Molecular defects of PORD include a Japanese founder mutation p.R457H, as well as various missense, nonsense, frameshift, and splice‐site mutations and exonic deletions. PORD leads to unique skeletal malformations referred to as Antley–Bixler syndrome, in addition to 46,XX and 46,XY disorders of sex development, pubertal failure, adrenal dysfunction, and maternal virilization during pregnancy. Such clinical features are ascribable to impaired activities of the POR‐dependent microsomal enzymes. PORD represents one form of congenital adrenal hyperplasia, although it can occur as a congenital malformation syndrome and a disorder of sex development. Phenotypic severity of PORD is highly variable and only partly depends on the residual activity of the mutant proteins. It is possible that PORD remains undiagnosed in several patients. Detailed hormonal assessment and molecular analysis are useful for diagnosis of PORD.
The length of discontinuous gas exchange cycles in lepidopteran pupae may serve as a mechanism for natural selection
Authors: Jõgar Katrin , Kuusik Aare , Metspalu Luule , Williams Ingrid H. , Ploomi Angela , Hiiesaar Külli , Luik Anne , Kivimägi Irja , Mänd Marika
Published: October 2014

Gas exchange is studied in diapausing pupae of Mamestra brassicae L., whose larvae are reared under identical conditions. The release of CO2 gas is recorded with infrared gaseous analyzers. Oxygen convective uptake into the tracheae and oxygen consumption rates are recorded by means of a constant‐volume coulometric respirometer. Outputs from both of these respirometry systems are combined with infrared actographs. All 3‐month‐old pupae of M. brassicae display a pattern of discontinuous gas exchange (DGE) cycles of CO2 gas release by bursts, although the lengths of these cycles varies between individuals. Some pupae exhibit long DGE cycles of at least 20 h in duration, with negligible CO2 gas release during interburst periods, and there is presumed to be a convective gas exchange at this time. As a result of a partial vacuum inside the tracheae, a large oxygen convective uptake always occurs at the start of the spiracular opening phase. Other pupae have short DGE cycles of less than 3 h in duration, with elevated CO2 gas release during the interburst period, when gas exchange is predominantly diffusive. The spiracular open phase in these pupae consists of frequent separate convective bursts of CO2 gas release, with the opening–closing rhythms of the spiracles, which are considered as O phase fluttering. The pupae with long DGE cycles exhibit extremely low metabolic rates and very low total water loss rates, whereas those with short DGE cycles have higher metabolic and total water loss rates. The pupae with long DGE cycles live approximately twice as long as those with short cycles; thus, the present study demonstrates that long DGE cycles confer a fitness benefit on pupae as a result of a lower metabolic rate associated with water economy, conferring on them a longer life.
Intraspecific acoustic communication and mechanical sensitivity of the tympanal ear of the gypsy moth Lymantria dispar
Authors: Rowland Eloise , Belton Peter , Schaefer Paul W. , Gries Gerhard
Published: October 2014

Tympanal ears of female gypsy moths Lymantria dispar dispar (L.) (Lepidoptera: Erebidae: Lymantriinae) are reportedly more sensitive than ears of conspecific males to sounds below 20 kHz. The hypothesis is tested that this differential sensitivity is a result of sex‐specific functional roles of sound during sexual communication, with males sending and females receiving acoustic signals. Analyses of sounds produced by flying males reveal a 33‐Hz wing beat frequency and 14‐kHz associated clicks, which remain unchanged in the presence of female sex pheromone. Females exposed to playback sounds of flying conspecific males respond with wing raising, fluttering and walking, generating distinctive visual signals that may be utilized by mate‐seeking males at close range. By contrast, females exposed to playback sounds of flying heterospecific males (Lymantria fumida Butler) do not exhibit the above behavioural responses. Laser Doppler vibrometry reveals that female tympana are particularly sensitive to frequencies in the range produced by flying conspecific males, including the 33‐Hz wing beat frequency, as well as the 7‐kHz fundamental frequency and 14‐kHz dominant frequency of associated clicks. These results support the hypothesis that the female L. dispar ear is tuned to sounds of flying conspecific males. Based on previous findings and the data of the present study, sexual communication in L. dispar appears to proceed as: (i) females emitting sex pheromone that attracts males; (ii) males flying toward calling females; and (iii) sound signals from flying males at close range inducing movement in females, which, in turn, provides visual signals that could orient males toward females.
Oculocutaneous Albinism in Sub‐Saharan Africa: Adverse Sun‐Associated Health Effects and Photoprotection
Authors: Wright Caradee Y. , Norval Mary , Hertle Richard W.
Published: October 2014

Oculocutaneous albinism (OCA) is a genetically inherited autosomal recessive condition. Individuals with OCA lack melanin and therefore are susceptible to the harmful effects of solar ultraviolet radiation, including extreme sun sensitivity, photophobia and skin cancer. OCA is a grave public health issue in sub‐Saharan Africa with a prevalence as high as 1 in 1000 in some tribes. This article considers the characteristics and prevalence of OCA in sub‐Saharan African countries. Sun‐induced adverse health effects in the skin and eyes of OCA individuals are reviewed. Sun exposure behavior and the use of photoprotection for the skin and eyes are discussed to highlight the major challenges experienced by these at‐risk individuals and how these might be best resolved.
Plasmodesmata‐located protein overexpression negatively impacts the manifestation of systemic acquired resistance and the long‐distance movement of Defective in Induced Resistance1 in Arabidopsis
Authors: Carella P. , Isaacs M. , Cameron R. K.
Published: October 2014

Systemic acquired resistance (SAR) is a plant defence response that provides immunity to distant uninfected leaves after an initial localised infection. The lipid transfer protein (LTP) Defective in Induced Resistance1 (DIR1) is an essential component of SAR that moves from induced to distant leaves following a SAR‐inducing local infection. To understand how DIR1 is transported to distant leaves during SAR, we analysed DIR1 movement in transgenic Arabidopsis lines with reduced cell‐to‐cell movement caused by the overexpression of Plasmodesmata‐Located Proteins PDLP1 and PDLP5. These PDLP‐overexpressing lines were defective for SAR, and DIR1 antibody signals were not observed in phloem sap‐enriched petiole exudates collected from distant leaves. Our data support the idea that cell‐to‐cell movement of DIR1 through plasmodesmata is important during long‐distance SAR signalling in Arabidopsis.
Foreign Capital, Spillovers and Export Performance in Emerging Economies: Evidence fromIndianITFirms
Authors: Kemme David M. , Nikolsko‐Rzhevskyy Alex , Mukherjee Deepraj
Published: October 2014

The role of foreign capital inflow, foreign direct investment (FDI) and foreign portfolio investment (FPI), on export behavior of both recipients and non‐recipient competing firms in the same sector often guides economic development policy. By using panel data ofIndianITfirms over 2000–2006, we show thatFDIreduces the sunk costs of entering foreign markets and therefore positively effects both the decision to export and the export propensity of recipient firms. Foreign portfolio investment has no effect on the decision to export, but it does marginally increase the volume of exports. Further, these positiveFDIandFPIrecipient effects do not spill‐over to non‐recipients.
When Carry Trades in Currency Markets are not Profitable
Authors: Baillie Richard T. , Cho Dooyeon
Published: October 2014

The success of the carry trade in international currency and money markets is related to the extent of the forward premium anomaly. We present evidence that the anomaly is a very time dependent phenomenon. We also formulate a model where theex postreturns from the carry trade are functionally related to the relative difference between the interest rate on the funding currency and the interest rate associated with the target currency; i.e. the relative interest rate opportunity (RIRO). We estimate a nonlinear smooth transition regime model that relates theRIROto the returns on the carry trade, and the estimated transition function then represents the time periods when the carry trade was profitable and when it was not. The analysis indicates that the desirability of carry trading has declined and for many currencies has actually become unprofitable since the financial crisis of 2008.
Toward a Minority Culture of Mobility: Immigrant Integration into the African‐American Middle Class
Authors: Clerge Orly
Published: October 2014

Two important social transformations have occurred since the 1960s: the rise of the Black middle class and the influx of immigrants from Latin, America, Asia and Africa. The cultural and economic outcomes for first‐ and second‐generation Black immigrants are often linked to the Black poor/underclass. However, we understand little about the ways in which the Black middle class is a potential pathway of integration for immigrants. This paper reviews the sociological debates on the socioeconomic incorporation of immigrants and the racial and ethnic relations of new and old African‐Americans. It discusses the important contributions of minority culture of mobility hypothesis for class‐based theories of immigrant integration. We draw from the literature on social stratification, race relations and immigrant incorporation in order to chime in on the conversation about how becoming socially mobile in America may mean having similar social experience as the African‐American or minority middle class. The paper also suggests ways to better analyze the relationship between identity, integration, space and generation in minority incorporation.
The Class Politics of Alternative Food: Informing Public Health Policy and Remedying Health Inequality
Authors: Lyson Mercedes C.
Published: October 2014

The past decade has witnessed an interesting coupling between alternative ways to produce and consume food (farmers' markets, Consumer Supported Agriculture (CSA) shares, and urban gardens to name a few) and individual health‐seeking. While much of this activity rests on an ideological rhetoric of individual choice and “lifestyleism” strongly correlated with social class, there have also been a host of very different government and policy efforts aimed at improving poor food environments and the vulnerable populations that inhabit them in the name of public health. Efforts such as zoning against fast food franchises, placing stipulations on what benefit programs like Supplemental Nutrition Assistance Program (SNAP) can be used for, and taxing foods deemed unhealthy are sparking public debate because they cut to the heart of many American socio‐political debates: the tension between individual liberties and government intervention. Based on existing scholarship of alternative food, health, and bodies, and the author's insights gleaned from ethnographic research, this article sheds light on the potential ineffectiveness of such public health efforts despite positive – and often times class‐conscious – intentions. Such an acknowledgement raises critical questions about who benefits and who misses out in alternative food projects. While this article situates these questions squarely in the American context, it also highlights the need for other situated studies that emphasize other countries' particular political, cultural, and economic contexts that shape contemporary food systems, and their accompanying moral politics.
Conceptual Remixing in Criminology: Tracing Durkheim and Marx's Influence on Etiological Theories of Crime
Authors: Dollar Cindy Brooks
Published: October 2014

Sociologists have previously argued that our current knowledge and inquiries stem from our standing on the shoulders of giants. Exactly how this occurs, however, may be less clear. This paper identifies how the works of two of the most valued classical social theorists – Durkheim and Marx – have influenced theories of crime causation. In doing so, I reveal that classical social theory continues to be relevant in the advancement of criminological thought. Identifying this lineage is crucial in developing more informed research and policy on crime and social control, which is especially important given the widespread interest in crime and delinquency among students (and citizens more generally).
Concurrent Bartonella henselae infection in a dog with panniculitis and owner with ulcerated nodular skin lesions
Authors: Rossi Michael A. , Balakrishnan Nandhakumar , Linder Keith E. , Messa Jacqueline B. , Breitschwerdt Edward B.
Published: October 2014

Background

Bartonella henselae, a Gram‐negative, zoonotic Alphaproteobacteria that infects erythrocytes, endothelial cells and dendritic cells, has previously been implicated as a cause of panniculitis in dogs and a human.

Animal and owner

An 8‐year‐old, spayed female Labrador retriever and its 78‐year‐old male owner living in the same household.

Methods and results

When preliminary and advanced testing failed to identify the cause of near‐simultaneous‐onset dermatological lesions, Bartonella serology, Bartonella Alphaproteobacteria growth medium (BAPGM) enrichment blood culture/PCR and immunohistochemistry were used to test specimens from the dog and owner. Bartonella henselae, genotype San Antonio 2 DNA was amplified and sequenced from the man's BAPGM enrichment blood culture and the dog's panniculitis lesion. The bacterium was visualized by immunohistochemistry in the dog's panniculitis lesion; however, neither the dog nor the owner was B. henselae seroreactive. Antibiotic therapy elicited dermatological improvement in both dog and owner.

Conclusions and clinical importance

Bartonella henselae is an emerging zoonotic pathogen that induces granulomatous inflammatory lesions in various tissues of animals, including humans. We conclude that this bacterium had a contributory or causative role in the development of the dermatological lesions in the dog and owner.
Contrast‐enhanced multidetector computed tomography to diagnose pulmonary thromboembolism in an awake dog with pyothorax
Authors: Ngwenyama Thandeka R. , Herring Jennifer M. , O'Brien Mauria , Hartman Susan K. , Galloway Kimberly A. , O'Brien Robert T.
Published: October 2014

Objectives

To (1) describe the use of contrast‐enhanced multidetector computed tomography (CE‐MDCT) for identifying pulmonary thromboembolism (PTE) in an awake dog with pyothorax, (2) report the first documented case of PTE associated with pyothorax in veterinary medicine, and (3) review diagnostic imaging modalities and therapeutic options for PTE.

Case Summary

A 5‐year, 4‐month‐old female neutered Labrador Retriever was presented for respiratory distress secondary to a pyothorax. The dog underwent thoracic exploratory surgery in which no underlying etiology was identified. Aerobic bacterial culture grewStreptococcus canis. The patient remained hypoxemic despite thoracocentesis and surgery. CE‐MDCT was performed without general anesthesia and showed luminal‐filling defects in the right cranial and right and left caudal lobar primary pulmonary arteries consistent with PTE. Anticoagulant therapy using unfractionated heparin was initiated. The dog responded well and was discharged 3 days postoperatively.

New or Unique Information Provided

To the authors’ knowledge, this is the first reported case of PTE diagnosed in a dog with pyothorax using CE‐MDCT.
Computing symmetry groups of polyhedra
Authors: Bremner David , Dutour Sikirić Mathieu , Pasechnik Dmitrii V. , Rehn Thomas , Schürmann Achill
Published: October 2014

Knowing the symmetries of a polyhedron can be very useful for the analysis of its structure as well as for practical polyhedral computations. In this note, we study symmetry groups preserving the linear, projective and combinatorial structure of a polyhedron. In each case we give algorithmic methods to compute the corresponding group and discuss some practical experiences. For practical purposes the linear symmetry group is the most important, as its computation can be directly translated into a graph automorphism problem. We indicate how to compute integral subgroups of the linear symmetry group that are used, for instance, in integer linear programming.
Estimating seabed scattering mechanisms via Bayesian model selection
Authors: Steininger Gavin , Dosso Stan E. , Holland Charles W. , Dettmer Jan
Published: October 2014

A quantitative inversion procedure is developed and applied to determine the dominant scattering mechanism (surface roughness and/or volume scattering) from seabed scattering-strength data. The classification system is based on trans-dimensional Bayesian inversion with the deviance information criterion used to select the dominant scattering mechanism. Scattering is modeled using first-order perturbation theory as due to one of three mechanisms: Interface scattering from a rough seafloor, volume scattering from a heterogeneous sediment layer, or mixed scattering combining both interface and volume scattering. The classification system is applied to six simulated test cases where it correctly identifies the true dominant scattering mechanism as having greater support from the data in five cases; the remaining case is indecisive. The approach is also applied to measured backscatter-strength data where volume scattering is determined as the dominant scattering mechanism. Comparison of inversion results with core data indicates the method yields both a reasonable volume heterogeneity size distribution and a good estimate of the sub-bottom depths at which scatterers occur.
Differences in acoustic features of vocalizations produced by killer whales cross-socialized with bottlenose dolphins
Authors: Musser Whitney B. , Bowles Ann E. , Grebner Dawn M. , Crance Jessica L.
Published: October 2014

Limited previous evidence suggests that killer whales (Orcinus orca) are capable of vocal production learning. However, vocal contextual learning has not been studied, nor the factors promoting learning. Vocalizations were collected from three killer whales with a history of exposure to bottlenose dolphins (Tursiops truncatus) and compared with data from seven killer whales held with conspecifics and nine bottlenose dolphins. The three whales' repertoires were distinguishable by a higher proportion of click trains and whistles. Time-domain features of click trains were intermediate between those of whales held with conspecifics and dolphins. These differences provided evidence for contextual learning. One killer whale spontaneously learned to produce artificial chirps taught to dolphins; acoustic features fell within the range of inter-individual differences among the dolphins. This whale also produced whistles similar to a stereotyped whistle produced by one dolphin. Thus, results provide further support for vocal production learning and show that killer whales are capable of contextual learning. That killer whales produce similar repertoires when associated with another species suggests substantial vocal plasticity and motivation for vocal conformity with social associates.
Reference hearing thresholds in an extended frequency range as a function of age
Authors: Jilek Milan , Šuta Daniel , Syka Josef
Published: October 2014

The ISO 7029 (2000) standard defines normative hearing thresholds H (dB hearing level) as a function of age Y (years), given by H = α(Y − 18)2, up to 8 kHz. The purpose of this study was to determine reference thresholds above 8 kHz. Hearing thresholds were examined using pure-tone audiometry over the extended frequency range 0.125–16 kHz, and the acquired values were used to specify the optimal approximation of the dependence of hearing thresholds on age. A sample of 411 otologically normal men and women 16–70 years of age was measured in both ears using a high-frequency audiometer and Sennheiser HDA 200 headphones. The coefficients of quadratic, linear, polynomial and power-law approximations were calculated using the least-squares fitting procedure. The approximation combining the square function H = α(Y − 18)2 with a power-law function H = β(Y − 18)1.5, both gender-independent, was found to be the most appropriate. Coefficient α was determined at frequencies of 9 kHz (α = 0.021), 10 kHz (α = 0.024), 11.2 kHz (α = 0.029), and coefficient β at frequencies of 12.5 kHz (β = 0.24), 14 kHz (β = 0.32), 16 kHz (β = 0.36). The results could be used to determine age-dependent normal hearing thresholds in an extended frequency range and to normalize hearing thresholds when comparing participants differing in age.
Colloquial Arabic vowels in Israel: A comparative acoustic study of two dialects
Authors: Amir Noam , Amir Ofer , Rosenhouse Judith
Published: October 2014

This study explores the acoustic properties of the vowel systems of two dialects of colloquial Arabic spoken in Israel. One dialect is spoken in the Galilee region in the north of Israel, and the other is spoken in the Triangle (Muthallath) region, in central Israel. These vowel systems have five short and five long vowels /i, i:, e, e:, a, a:, o, o:, u, u:/. Twenty men and twenty women from each region were included, uttering 30 vowels each. All speakers were adult Muslim native speakers of these two dialects. The studied vowels were uttered in non-pharyngeal and non-laryngeal environments in the context of CVC words, embedded in a carrier sentence. The acoustic parameters studied were the two first formants, F0, and duration. Results revealed that long vowels were approximately twice as long as short vowels and differed also in their formant values. The two dialects diverged mainly in the short vowels rather than in the long ones. An overlap was found between the two short vowel pairs /i/-/e/ and /u/-/o/. This study demonstrates the existence of dialectal differences in the colloquial Arabic vowel systems, underlining the need for further research into the numerous additional dialects found in the region.
Rapid estimation of high-parameter auditory-filter shapes
Authors: Shen Yi , Sivakumar Rajeswari , Richards Virginia M.
Published: October 2014

A Bayesian adaptive procedure, the quick-auditory-filter (qAF) procedure, was used to estimate auditory-filter shapes that were asymmetric about their peaks. In three experiments, listeners who were naive to psychoacoustic experiments detected a fixed-level, pure-tone target presented with a spectrally notched noise masker. The qAF procedure adaptively manipulated the masker spectrum level and the position of the masker notch, which was optimized for the efficient estimation of the five parameters of an auditory-filter model. Experiment I demonstrated that the qAF procedure provided a convergent estimate of the auditory-filter shape at 2 kHz within 150 to 200 trials (approximately 15 min to complete) and, for a majority of listeners, excellent test-retest reliability. In experiment II, asymmetric auditory filters were estimated for target frequencies of 1 and 4 kHz and target levels of 30 and 50 dB sound pressure level. The estimated filter shapes were generally consistent with published norms, especially at the low target level. It is known that the auditory-filter estimates are narrower for forward masking than simultaneous masking due to peripheral suppression, a result replicated in experiment III using fewer than 200 qAF trials.
The role of stimulus complexity, spectral overlap, and pitch for gap-detection thresholds in young and old listeners
Authors: Heinrich A. , de la Rosa S. , Schneider B. A.
Published: October 2014

Thresholds for detecting a gap between two complex tones were determined for young listeners with normal hearing and old listeners with mild age-related hearing loss. The leading tonal marker was always a 20-ms, 250-Hz complex tone with energy at 250, 500, 750, and 1000 Hz. The lagging marker, also tonal, could differ from the leading marker with respect to fundamental frequency (f0), the presence versus absence of energy at f0, and the degree to which it overlapped spectrally with the leading marker. All stimuli were presented with steeper (1 ms) and less steep (4 ms) envelope rise and fall times. F0 differences, decreases in the degree of spectral overlap between the markers, and shallower envelope shape all contributed to increases in gap-detection thresholds. Age differences for gap detection of complex sounds were generally small and constant when gap-detection thresholds were measured on a log scale. When comparing the results for complex sounds to thresholds obtained for pure-tones in a previous study by Heinrich and Schneider [(2006). J. Acoust. Soc. Am. 119, 2316–2326], thresholds increased in an orderly fashion from markers with identical (within-channel) pure tones to different (between-channel) pure tones to complex sounds. This pattern of results was true for listeners of both ages although younger listeners had smaller thresholds overall.
Modeling power law absorption and dispersion in viscoelastic solids using a split-field and the fractional Laplacian
Authors: Treeby Bradley E. , Cox B. T.
Published: October 2014

The absorption of compressional and shear waves in many viscoelastic solids has been experimentally shown to follow a frequency power law. It is now well established that this type of loss behavior can be modeled using fractional derivatives. However, previous fractional constitutive equations for viscoelastic media are based on temporal fractional derivatives. These operators are non-local in time, which makes them difficult to compute in a memory efficient manner. Here, a fractional Kelvin-Voigt model is derived based on the fractional Laplacian. This is obtained by splitting the particle velocity into compressional and shear components using a dyadic wavenumber tensor. This allows the temporal fractional derivatives in the Kelvin-Voigt model to be replaced with spatial fractional derivatives using a lossless dispersion relation with the appropriate compressional or shear wave speed. The model is discretized using the Fourier collocation spectral method, which allows the fractional operators to be efficiently computed. The field splitting also allows the use of a k-space corrected finite difference scheme for time integration to minimize numerical dispersion. The absorption and dispersion behavior of the fractional Laplacian model is analyzed for both high and low loss materials. The accuracy and utility of the model is then demonstrated through several numerical experiments, including the transmission of focused ultrasound waves through the skull.
An objective measure for the sensitivity of room impulse response and its link to a diffuse sound field
Authors: Prislan Rok , Brunskog Jonas , Jacobsen Finn , Jeong Cheol-Ho
Published: October 2014

This study is relevant to acoustic measurements in reverberation rooms such as measurements of sound transmission, sound absorption, and sound power levels of noise sources. The study presents a quantitative measure for the diffuseness in a room, which is first introduced theoretically and subsequently examined experimentally. The sensitivity of a room due to changes in the initial conditions is quantified by measuring a pair of impulse responses in a room differing only in the sound source position. Such changes are linked to mixing and the diffuse sound field. The measure is based on the maximum of the absolute value of the cross-correlation between the time windowed sections of the two impulse responses. By integrating this quantity normalized by the energy of the impulse response of the room, a single number rating is obtained. Results based on three sets of experiments indicate that the diffusers and absorbers in the room influence the proposed sensitivity measures systematically.
Reactive control of subsonic axial fan noise in a duct
Authors: Liu Y. , Choy Y. S. , Huang L. , Cheng L.
Published: October 2014

Suppressing the ducted fan noise at low frequencies without varying the flow capacity is still a technical challenge. This study examines a conceived device consisting of two tensioned membranes backed with cavities housing the axial fan for suppression of the sound radiation from the axial fan directly. The noise suppression is achieved by destructive interference between the sound fields from the axial fan of a dipole nature and sound radiation from the membrane via vibroacoustics coupling. A two-dimensional model with the flow effect is presented which allows the performance of the device to be explored analytically. The air flow influences the symmetrical behavior and excites the odd in vacuo mode response of the membrane due to kinematic coupling. Such an asymmetrical effect can be compromised with off-center alignment of the axial fan. Tension plays an important role to sustain the performance to revoke the deformation of the membrane during the axial fan operation. With the design of four appropriately tensioned membranes covered by a cylindrical cavity, the first and second blade passage frequencies of the axial fan can be reduced by at least 20 dB. The satisfactory agreement between experiment and theory demonstrates that its feasibility is practical.
Isentropic wave propagation in a viscous fluid with uniform flow confined by a lined pipeline
Authors: Chen Yong , Huang Yiyong , Chen Xiaoqian , Bai Yuzhu
Published: October 2014

The axisymmetric wave propagation in a viscous fluid with the presence of a uniform flow confined by a circular pipeline is investigated. Particular considerations are imposed on the features of the acoustic wave propagating in the liquid where the thermal conduction is neglected. The boundary constraints at the wall are reasonably discussed for both lined-walled and rigid-walled pipelines. Numerical comparisons of the phase velocity and wave attenuation among three different boundary configurations (rigid wall, steel-composed wall, and aluminum-composed wall) are presented. Meanwhile, the effects of the fluid viscosity and acoustic impedance are coherently analyzed. In the end, parametric analysis of the influence of the acoustic impedance is given in the case of a steel-composed pipeline.
Fast and slow wave detection in bovine cancellous bone in vitro using bandlimited deconvolution and Prony's method
Authors: Wear Keith , Nagatani Yoshiki , Mizuno Katsunori , Matsukawa Mami
Published: October 2014

Fast and slow waves were detected in a bovine cancellous bone sample for thicknesses ranging from 7 to 12 mm using bandlimited deconvolution and the modified least-squares Prony's method with curve fitting (MLSP + CF). Bandlimited deconvolution consistently isolated two waves with linear-with-frequency attenuation coefficients as evidenced by high correlation coefficients between attenuation coefficient and frequency: 0.997 ± 0.002 (fast wave) and 0.986 ± 0.013 (slow wave) (mean ± standard deviation). Average root-mean-squared (RMS) differences between the two algorithms for phase velocities were 5 m/s (fast wave, 350 kHz) and 13 m/s (slow wave, 750 kHz). Average RMS differences for signal loss were 1.6 dB (fast wave, 350 kHz) and 0.4 dB (slow wave, 750 kHz). Phase velocities for thickness = 10 mm were 1726 m/s (fast wave, 350 kHz) and 1455 m/s (slow wave, 750 kHz). Results show support for the model of two waves with linear-with frequency attenuation, successful isolation of fast and slow waves, good agreement between bandlimited deconvolution and MLSP + CF as well as with a Bayesian algorithm, and potential variations of fast and/or slow wave properties with bone sample thickness.
Delphinid behavioral responses to incidental mid-frequency active sonar
Authors: Henderson E. Elizabeth , Smith Michael H. , Gassmann Martin , Wiggins Sean M. , Douglas Annie B. , Hildebrand John A.
Published: October 2014

Opportunistic observations of behavioral responses by delphinids to incidental mid-frequency active (MFA) sonar were recorded in the Southern California Bight from 2004 through 2008 using visual focal follows, static hydrophones, and autonomous recorders. Sound pressure levels were calculated between 2 and 8 kHz. Surface behavioral responses were observed in 26 groups from at least three species of 46 groups out of five species encountered during MFA sonar incidents. Responses included changes in behavioral state or direction of travel, changes in vocalization rates and call intensity, or a lack of vocalizations while MFA sonar occurred. However, 46% of focal groups not exposed to sonar also changed their behavior, and 43% of focal groups exposed to sonar did not change their behavior. Mean peak sound pressure levels when a behavioral response occurred were around 122 dB re: 1 μPa. Acoustic localizations of dolphin groups exhibiting a response gave insight into nighttime movement patterns and provided evidence that impacts of sonar may be mediated by behavioral state. The lack of response in some cases may indicate a tolerance of or habituation to MFA sonar by local populations; however, the responses that occur at lower received levels may point to some sensitization as well.
High-resolution measurement of a bottlenose dolphin's (Tursiops truncatus) biosonar transmission beam pattern in the horizontal plane
Authors: Finneran James J. , Branstetter Brian K. , Houser Dorian S. , Moore Patrick W. , Mulsow Jason , Martin Cameron , Perisho Shaun
Published: October 2014

Previous measurements of toothed whale echolocation transmission beam patterns have utilized few hydrophones and have therefore been limited to fine angular resolution only near the principal axis or poor resolution over larger azimuthal ranges. In this study, a circular, horizontal planar array of 35 hydrophones was used to measure a dolphin's transmission beam pattern with 5° to 10° resolution at azimuths from −150° to +150°. Beam patterns and directivity indices were calculated from both the peak-peak sound pressure and the energy flux density. The emitted pulse became smaller in amplitude and progressively distorted as it was recorded farther off the principal axis. Beyond ±30° to 40°, the off-axis signal consisted of two distinct pulses whose difference in time of arrival increased with the absolute value of the azimuthal angle. A simple model suggests that the second pulse is best explained as a reflection from internal structures in the dolphin's head, and does not implicate the use of a second sound source. Click energy was also more directional at the higher source levels utilized at longer ranges, where the center frequency was elevated compared to that of the lower amplitude clicks used at shorter range.