bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk of Stroke Associated With Use of Estrogen Containing Contraceptives in Women With Migraine: A Systematic Review
Authors: Sheikh Huma U. , Pavlovic Jelena , Loder Elizabeth , Burch Rebecca
Published: November 2017

Objective

Migraine with aura has been associated with increased risk of ischemic and hemorrhagic stroke. Prior studies have shown a further increase in risk in women using combined hormonal contraceptives (CHCs). This has led to guidelines recommending against use of CHCs in this population. We sought to assess whether the risk of stroke is associated with the dose of estrogen and whether there is evidence of synergism between migraine and CHCs. We also sought to assess whether an interaction effect exists between migraine and CHCs.

Methods

We searched PubMed, the Cochrane Library, and EMBASE from inception through January 2016 for relevant English‐language studies of adults, of any design. We included studies that examined exposure to CHCs and reported outcomes of ischemic or hemorrhagic stroke. Data extraction and assessment of study quality were conducted independently by reviewer pairs and quality was assessed with the GRADE and Newcastle Ottawa scales.

Results

Of 2480 records, 15 studies met inclusion criteria and six provided odds ratios for the relevant population. The point estimates for the odds ratios for ischemic stroke in women with migraine who used CHCs with any dose of estrogen ranged from 2.08 to 16.9. Studies were generally small and confidence intervals were wide. No studies reported odds ratios for stroke risk as a function of estrogen dose in women with migraine, largely due to insufficient sample sizes. No interaction effect between migraine and CHCs was seen in the seven studies that assessed this. One study differentiated risk by presence or absence of migraine aura and found an increased risk in the migraine with aura population (OR 6.1; CI 3.1 to 12.1 in migraine with aura vs 1.8; CI 1.1 to 2.9 in the migraine without aura group). Studies generally had high Newcastle Ottawa scores and low GRADE levels of evidence. No studies met all three supplementary quality criteria (assessed migraine subtype, used International Classification of Headache Disorders criteria for diagnosis of migraine, and stratified risk by estrogen dose).

Conclusions

This systematic review shows a lack of good quality studies assessing risk of stroke associated with low dose estrogen use in women with migraine. Further study in this area is needed. The available evidence is consistent with an additive increase in stroke risk with CHC use in women with migraine with aura. Since the absolute risk of stroke is low even in the presence of these risk factors, use of CHCs in women who have migraine with aura should be based on an individualized assessment of harms and benefits.
15. The Morphology of the Ostrich Chondrocranium
Authors: Brock Gwendolen T.
Published: November 2017

Summary

The main points of interset which have emerged from the study of the ostrich chondrocranium are:–

 Confirmation of de Beer's account of the formation of an olfactory canal by the apposition of the anterior orbital cartilages to the nasal septum and backwardly directed parietotectals.

 Confirmation of de Beer's account of the formation of a pila antotica spuria, separating V 1 from V 2, as a secondary backward extension of the original normal pila antotica.

 There is only a very short infrapolar process in the ostrich; the lateral carotid foramen is formed by the extreme flexure of the polar-trabecular against the parachordal region and the fusion of the two regions below the carotid artery.

 The origin of the metotic process rudiment in the ostrich throws no light on the nature of this process. De Beer's suggestion that it represents a number of fused cranial ribs is neither confirmed nor refuted, since the earliest mesenchyme is attached both to the otic capsule and to the occipital region.

 The columella auris has a low backwardly directed suprastapedial and the chorda tympani takes a pre-columella course; the origin of the nerve is as a normal post-trematic branch of the hyomandibular nerve. This condition is compared with that in other birds.

 On general considerations, it is shown that the ostrich chondrocranium conforms closely to the typical avian chondrocranium, with very few indications of a primitive nature.
Hepatic peroxisome proliferator‐activated receptor alpha mediates the major metabolic effects of Wy‐14643
Authors: Li Guolin , Brocker Chad N , Xie Cen , Yan Tingting , Noguchi Audrey , Krausz Kristopher W , Xiang Rong , Gonzalez Frank J
Published: November 2017

Background and Aim

Peroxisome proliferator‐activated receptor alpha (PPARα) is a molecular target of various fibrate drugs clinically used to lower serum lipids. However, the tissue‐specific functions of PPARα remain to be elucidated. This study aimed to explore the tissue‐specific functions of PPARα in response to Wy‐14643.

Methods

A hepatocyte‐specific Ppara knockout mouse line was used to explore the impact of hepatic PPARα activity on the systemic response to treatment with the potent PPARα agonist Wy‐14643.

Results

Wy‐14643 mainly activated hepatic PPARα and regulated the expression of PPARα target genes in liver. Hepatic Ppara disruption abolished the triglyceride lowering effects of Wy‐14643, prevented agonist‐induced hypophagia, and ablated PPARα target gene response in the liver.

Conclusions

These findings indicate that Wy‐14643 treatment mainly activates hepatic PPARα, and the hypolipidemic and hypophagic effects of Wy‐14643 are dependent on PPARα activation within hepatocytes.
Soft versus Hard Commitments: A Test on Savings Behaviors
Authors: Burke Jeremy , Luoto Jill , Perez‐Arce Francisco
Published: November 2017

Commitment devices restricting future behavior have demonstrated promise in helping individuals improve their savings behavior, yet often suffer from low take‐up. We test a new “soft” commitment account that asks borrowers to think about their savings goals, how it would feel to achieve them, and make a pledge to work toward these goals, yet has no external restrictions on savings behavior. In a six‐month randomized experiment among consumers that find it difficult to meet their savings needs, we find that such soft commitments can significantly increase initial savings relative to either a hard commitment account (that prevents withdrawals) or a traditional savings account. In addition, the soft commitments significantly increased final savings balances relative to no form of commitment and were particularly effective for impatient individuals. Despite the lower initial take‐up, the hard commitment account proved most effective in building savings balances among our participants at the end of 6 months.
Meta‐Analysis of Coefficient Alpha: A Reliability Generalization Study
Authors: Greco Lindsey M. , O'Boyle Ernest H. , Cockburn Bethany S. , Yuan Zhenyu
Published: November 2017

Increasing precision of measurement is a goal of scientific advancement, but Nunnally's (1978) .70 benchmark for coefficient alpha (alpha) has remained the omnibus test for reliability for nearly 40 years. This likely arises due to there only being scattered empirical evidence of the degree to which the field has met or surpassed this standard. Using meta‐analytic techniques known as reliability generalization (RG), we cumulate alphas across 36 commonly used individual differences, attitudes, and behaviours from 1675 independent samples (N = 991,588). Our primary finding is that alphas almost always exceed .70 and generally fall above .80. In addition, we identified factors that moderate alpha including the specific measure used, the number of scale items, and the rater. The study provides baseline alphas that can be used for research planning and design; it also offers best practices for RG and notes the benefits of RG for understanding systematic fluctuations in reliability.
Posterior reversible encephalopathy syndrome and hyponatremia associated with localized herpes zoster infection treated with acyclovir
Authors: Yaguchi Masamitsu , Yaguchi Hisa
Published: November 2017

We report a 91‐year‐old woman with posterior reversible encephalopathy syndrome (PRES) and hyponatremia that developed during the course of localized herpes zoster infection of the L2 dermatome treated with acyclovir. Hyponatremia was consistent with syndrome of inappropriate antidiuresis (SIAD). Localized herpes zoster rarely causes SIAD. PRES may be related to hyponatremia associated with localized herpes zoster.
Extracellular proteinases of Candida species pathogenic yeasts
Authors: Rapala‐Kozik M. , Bochenska O. , Zajac D. , Karkowska‐Kuleta J. , Gogol M. , Zawrotniak M. , Kozik A.
Published: November 2017

The increased incidence of severe disseminated infections caused by the opportunistic yeast‐like fungi Candida spp. highlights the urgent need for research into the major virulence factors of these pathogens—extracellular aspartic proteinases of the candidapepsin and yapsin families. Classically, these enzymes were considered to be generally destructive factors that damage host tissues and provide nutrients for pathogen propagation. However, in recent decades, novel and more specific functions have been suggested for extracellular candidal proteinases. These include contributions to cell wall maintenance and remodeling, the formation of polymicrobial biofilms, adhesion to external protective barriers of the host, the deregulation of host proteolytic cascades (such as the complement system, blood coagulation and the kallikrein–kinin system), a dysregulated host proteinase–inhibitor balance, the inactivation of host antimicrobial peptides, evasion of immune responses and the induction of inflammatory mediator release from host cells. Only a few of these activities recognized in Candida albicans candidapepsins have been also confirmed in other Candida species, and characterization of Candida glabrata yapsins remains limited.
Serological evidence for the co‐circulation of two lineages of influenza D viruses in equine populations of the Midwest United States
Authors: Nedland H. , Wollman J. , Sreenivasan C. , Quast M. , Singrey A. , Fawcett L. , Christopher‐Hennings J. , Nelson E. , Kaushik R. S. , Wang D. , Li F.
Published: November 2017

Influenza D virus (IDV) is a newly described influenza type of the Orthomyxoviridae virus family that was first isolated from diseased swine in 2011 and has subsequently been detected in cattle around the world in 2014. In addition, serological evidence for IDV infection in humans has been recently established. Despite all the progress, the full range of susceptible hosts for this novel virus has yet to be determined, but includes swine, bovine, small ruminants and human. This study was designed to determine if equine is a possible host to this newly emerging influenza virus. Three hundred and sixty‐four equine serum samples were collected in 2015 from 141 farms within the Midwestern United States. Serum samples were examined using hemagglutination inhibition (HI) assay against two established IDV lineages (D/OK and D/660) and one IDV‐related human ICV lineage (C/JHB). Results of this study showed 44 (44 of 364, 12%) samples positive for antibodies against D/OK, 39 (39 of 364, 11%) samples positive for antibodies against D/660, and 41 (41 of 364, 11%) samples positive for antibodies against C/JHB. A subset of these samples was further confirmed via microtitre neutralization (MN) assay. Our data demonstrated that horses are susceptible to two lineages of IDV, and that these viruses were present in equine populations throughout multiple Midwestern states of the United States. These findings continue to support the need for further surveillance of IDV viruses in agricultural species to work towards a better understanding of the full host range and natural reservoirs of influenza D virus.
Porcine respiratory disease complex after the introduction of H1N1/2009 influenza virus in Brazil
Authors: Rech R. R. , Gava D. , Silva M. C. , Fernandes L. T. , Haach V. , Ciacci‐Zanella J. R. , Schaefer R.
Published: November 2017

From 2009 to 2015, 74 lungs from suckling (6.8%), nursing (70.3%), fattening (20.3%) pigs and pregnant sows (2.7%) with respiratory signs from pig farms in Southern Brazil were submitted to a diagnostic laboratory for necropsy and/or histologic examination and screening for respiratory agents by RT‐qPCR, immunohistochemistry (IHC), virus isolation (VI) and subtyping for influenza A virus (IAV), IHC and nested PCR for Mycoplasma hyopneumoniae (Mhyo), PCR for porcine circovirus 2 (PCV2), RT‐qPCR for porcine reproductive and respiratory syndrome virus (PRRSV) and bacterial culture. All lung samples were positive for IAV using RT‐qPCR. Seventy‐two lungs had histologic lesions associated with acute to subacute IAV infection characterized by necrotizing bronchiolitis/bronchitis or bronchointerstitial pneumonia with lymphocytic peribronchiolitis and bronchiolar/bronchial hyperplasia, respectively. Forty‐nine lungs (66.2%) were positive by IHC for IAV nucleoprotein. The H1N1/2009 was the most common subtype and the only IAV detected in 58.1% of lungs, followed by H1N2 (9.5%) and H3N2 (6.8%). Coinfection of IAV and Mhyo was seen in 23 (31%) cases. Although 14.9% of the lungs were positive for PCV2 using PCR, no suggestive lesions of PCV2 disease were observed. Porcine reproductive and respiratory syndrome virus (PRRSV) was not detected, consistent with the PRRS‐free status of Brazil. Secondary bacterial infections (8/38) were associated with suppurative bronchopneumonia and/or pleuritis. Primary IAV infection with Mhyo coinfection was the most common agents found in porcine respiratory disease complex (PRDC) in pigs in Southern Brazil.
WhatsApp Messenger as a Learning Tool: An Investigation of Pre-service Teachers’ Learning without Instructor Presence
Authors: Alenazi Ali A.
Published: November 2017

This study investigated the extent to which pre-service teachers can utilize WhatsApp Messenger to create an effective learning platform without instructor interference. Twenty-six male pre-service teachers created a WhatsApp group and interacted through it independently for nine weeks. Each pre-service teacher was required to share a minimum of two posts on a weekly basis, for eighteen posts in total. The pre-service teachers were given clear rules for participation that included a wide range of topics and the definition of an accepted post. The frequency of posts was recorded to determine the magnitude of participation. Focus group interviews were conducted to investigate reasons behind each pre-service teacher’s magnitude of participation. The results of the study revealed that the participation rate of the entire group was unsatisfactory (57%), with only six pre-service teachers meeting the minimum required number of posts. Interestingly, these six pre-service teachers created a small but unique norm of learning environment by regulating their own and other peers’ performance as well. The reasons for the magnitude of participation, additional results, and implications of the study findings for educational settings are discussed.
Ansiedad, Estrés y Obesidad en una muestra de adolescentes de México Anxiety, Stress and Obesity in a sample of adolescents in Mexico
Authors: Pompa Guajardo Edith Gerardina , Meza Peña Cecilia
Published: November 2017

Para analizar la relación entre sobrepeso/obesidad, género, ansiedad y estrés se realizó un estudio transversal correlacional en donde participaron 849 adolescentes del norte de México. Los análisis de revelaron que las mujeres con sobrepeso y obesidad presentan mayores niveles de estrés y de ansiedad, así como mayor probabilidad de manifestar ambas condiciones. Se concluye que el género y la obesidad son condiciones de riesgo para la manifestación de estrés y ansiedad.

To analyze the relationship between overweight / obesity, gender, anxiety and stress a correlational cross-sectional study was developed, participating 849 teenagers from northern Mexico. The analysis revealed that overweight and obese women have higher levels of stress and anxiety, and that they are more likely to manifest both conditions. It is concluded that gender and obesity are risk conditions for the manifestation of stress and anxiety.
Evaluación de una intervención para la mejora de las competencias de regulación interpersonal del afecto y el bienestar laboral en una muestra de operadores penitenciarios del Uruguay.
Authors: Martínez-Iñigo David , Crego Antonio
Published: November 2017

La utilización de estrategias controladas para la regulación interpersonal (ECRI) del afecto de la población reclusa puede afectar al bienestar de los operadores de prisiones. Según estudios previos, las ECRIs orientadas a mejorar el afecto de otros incrementan el bienestar del agente que las ejecuta. Al contrario, las ECRIs orientadas a empeorar el afecto deterioran su bienestar. Estos resultados se explican, según el Modelo de Fuerza de la Autorregulación y el Modelo de Conservación de Recursos, a partir del equilibrio entre el consumo de recursos de auto-regulación ligados a la ECRIs y los efectos diferenciales de dichas estrategias sobre los procesos de recuperación de este tipo de recursos. El presente estudio, basado en un diseño cuasi-experimenta, evalúa la eficacia de un programa de formación en ECRI orientado a la mejora del bienestar. Los resultados reflejan un mayor nivel de bienestar y un menor nivel de ECRIS orientadas al empeoramiento en los participantes en la formación (N= 21), cuando se comparan el un grupo de control (N= 18). No se encontraron diferencias significativas para las ECRIs de mejora. Los análisis de regresión jerárquica muestran que los cambios en las ECRIS de empeoramiento predicen negativamente los cambios en el nivel de bienestar.
Evaluación psicológica del síndrome de burnout en profesores de educación primaria en la Comunidad de Madrid: comparación entre centros públicos y concertados
Authors: Solera Hernández Eva , Gutiérrez Gómez-Calcerrada Sonia , Palacios-Ceña Domingo
Published: November 2017

Este estudio explora el estado psíquico de profesores de tercer ciclo de primaria de varios centros públicos y concertados de la Comunidad de Madrid. Se evaluó la sintomatología ansiosa y depresiva y el síndrome de Burnout mediante la Escala de Ansiedad y Depresión en Hospital (HADS) y el Cuestionario de Burnout del Profesorado (CBP-R). Los resultados indicaron que, aunque los docentes de colegios concertados puntúan más alto en sintomatología ansiosa, con diferencias estadísticamente significativas, los profesores de colegios públicos presentan mayor Burnout, de modo estadísticamente significativo, en las escalas de cuestiones organizacionales, supervisión y reconocimiento.
Falacias sobre el valor p compartidas por profesores y estudiantes universitarios
Authors: Badenes-Ribera Laura , Frias-Navarro Dolores
Published: November 2017

Resumen La “Práctica Basada en la Evidencia” exige que los profesionales valoren de forma crítica los resultados de las investigaciones psicológicas. Sin embargo, las interpretaciones incorrectas de los valores p de probabilidad son abundantes y repetitivas. Estas interpretaciones incorrectas afectan a las decisiones profesionales y ponen en riesgo la calidad de las intervenciones y la acumulación de un conocimiento científico válido. Identificar el tipo de falacia que subyace a las decisiones estadísticas es fundamental para abordar y planificar estrategias de educación estadística dirigidas a intervenir sobre las interpretaciones incorrectas. En consecuencia, el objetivo de este estudio es analizar la interpretación del valor p en estudiantes y profesores universitarios de Psicología. La muestra estuvo formada por 161 participantes (43 profesores y 118 estudiantes). La antigüedad media como profesor fue de 16.7 años (DT = 10.07). La edad media de los estudiantes fue de 21.59 (DT = 1.3). Los hallazgos sugieren que los estudiantes y profesores universitarios no conocen la interpretación correcta del valor p. La falacia de la probabilidad inversa presenta mayores problemas de comprensión. Además, se confunde la significación estadística y la significación práctica o clínica. Estos resultados destacan la necesidad de la educación estadística y re-educación estadística. Abstract The "Evidence Based Practice" requires professionals to critically assess the results of psychological research. However, incorrect interpretations of p values of probability are abundant and repetitive. These misconceptions affect professional decisions and compromise the quality of interventions and the accumulation of a valid scientific knowledge. Identifying the types of fallacies that underlying statistical decisions is fundamental for approaching and planning statistical education strategies designed to intervene in incorrect interpretations. Therefore, the aim of this study is to analyze the interpretation of p value among college students of psychology and academic psychologist. The sample was composed of 161 participants (43 academic and 118 students). The mean number of years as academic was 16.7 (SD = 10.07). The mean age of college students was 21.59 years (SD = 1.3). The findings suggest that college students and academic do not know the correct interpretation of p values. The fallacy of the inverse probability presents major problems of comprehension. In addition, statistical significance and practical significance or clinical are confused. There is a need for statistical education and statistical re-education.
Gestión del tiempo y procrastinación en la educación superior
Authors: Garzón Umerenkova Angélica , Gil Flores Javier
Published: November 2017

La procrastinación constituye un fallo de las conductas autorregulatorias que conlleva efectos negativos a nivel académico. Analizamos el valor de la gestión del tiempo como variable predictora de la procrastinación, estudiando una muestra de 494 estudiantes universitarios colombianos de primer año, que fueron clasificados en dos grupos en función de su grado de procrastinación académica. Hemos recogido información sobre sus conductas de gestión del tiempo, medidas a través de una versión española del Time Management Behavior Questionnaire (TMBQ). Tras construir un modelo de regresión logística, las puntuaciones en la sub-escala establecimiento de objetivos y prioridades junto con percepción sobre el control del tiempo, resultan ser buenas predictoras del nivel de procrastinación, a diferencia de herramientas para la gestión del tiempo o preferencias por la desorganización. Entre las características demográficas (sexo, edad y dedicación), juega un papel relevante la condición de estudiante con dedicación compartida entre estudio y trabajo.
El papel de la comunicación, la motivación y el disfrute sobre el compromiso en practicantes de musculación
Authors: Borges-Silva Fernanda , Huéscar Elisa , Moreno-Murcia Juan Antonio
Published: November 2017

El objetivo de este estudio fue comprobar el poder de predicción de las formas de comunicación del monitor de musculación, la motivación intrínseca y el disfrute en la actividad, sobre el compromiso deportivo de usuarios de salas de musculación. Participaron 287 personas practicantes de musculación de centros deportivos, a los que les midió la percepción de comunicación y las barreras de comunicación con el técnico, la motivación intrínseca, el disfrute y el grado de compromiso deportivo. El análisis de regresión lineal mostró que el uso de estrategias de comunicación adecuadas por parte del técnico de musculación, así como altos niveles de motivación intrínseca y de disfrute en la práctica predecían el compromiso futuro de los practicantes. De esta forma, el uso de estrategias eficaces de comunicación del técnico de musculación durante la interacción con los practicantes aumentaría la motivación de las personas, posibilitando una mayor adherencia a la práctica.
Three-Dimensional Vibration of the Crankshaft of a Large Marine Diesel Engine Under a Mixed Thermo-Elastic-Hydro-Dynamic Lubrication Coupling Between Flexible Crankshaft and Engine Block
Authors: Wei Lidui , Wei Haijun , Du Haiping , Duan Shulin
Published: November 2017

To predict the vibration characteristics of the crankshaft of the larger marine diesel engine accurately and comprehensively, based on the finite element models of the crankshaft and the engine block reduced by a component mode synthesis (CMS) method as well as extended Reynolds equation and Greenwood-Tripp theory, a mixed thermo-elasto-hydro-dynamic lubrication coupling model between a whole flexible engine block and a rotating flexible crankshaft is set up. According to this strongly coupled nonlinear model, the torsional-axial-lateral three-dimensional (3D) vibration of the crankshaft can be calculated simultaneously. The method is verified through comparison with other computational methods. Also, the vibrations are compared under different support models and whether to consider the effect of temperature. Specific 3D vibrations are displayed, and some stage nonlinear characteristics are shown in 3D direction. The modeling method will contribute to reveal the vibration mechanism and optimize the design of the shafting system.
A Lumped Thermodynamic Model of Gas Turbine Blade Cooling: Prediction of First-Stage Blades Temperature and Cooling Flow Rates
Authors: Masci Roberta , Sciubba Enrico
Published: November 2017

Turbine inlet temperatures (TIT) of 1500–2000 K have become a sort of standard for most modern advanced applications. First-stage blades are obviously the most exposed components to such hot gases, and thus they need proper cooling. In the preliminary design of the blades and their cooling system, designers must rely on simple models that can be further refined at a later stage, in order to have an approximate but valuable set of guidelines and to reach a feasible first-order configuration. In this paper, a simple lumped thermodynamic model of blade cooling is proposed. It is based on mass/energy balances and heat transfer correlations, and it predicts a one-dimensional temperature profile on the blade external surface along the chord for a given gas temperature profile, as well as the required cooling air flow rates to prevent blade material from creep. The greatest advantage of the model is that it can be easily adapted to any operating condition, process parameter, and blade geometry, which makes it well suited to the last technological trends, namely, the investigation of new cooling methods and alternative coolants instead of air. Therefore, the proposed model is expected to be a useful tool in the field of innovative gas turbine cycle analysis, replacing more computationally intensive and very time-consuming models.
Theoretical Analysis of Brush Seals Leakage Using Local Computational Fluid Dynamics Estimated Permeability Laws
Authors: Deville Lilas , Arghir Mihai
Published: November 2017

Brush seals are a mature technology that has generated extensive experimental and theoretical work. Theoretical models range from simple correlations with experimental results to advanced numerical approaches coupling the bristles deformation with the flow in the brush. The present work follows this latter path. The bristles of the brush are deformed by the pressure applied by the flow, by the interference with the rotor and with the back plate. The bristles are modeled as linear beams but a nonlinear numerical algorithm deals with the interferences. The brush with its deformed bristles is then considered as an anisotropic porous medium for the leakage flow. Taking into account, the variation of the permeability with the local geometric and flow conditions represents the originality of the present work. The permeability following the principal directions of the bristles is estimated from computational fluid dynamics (CFD) calculations. A representative number of bristles are selected for each principal direction and the CFD analysis domain is delimited by periodicity and symmetry boundary conditions. The parameters of the CFD analysis are the local Reynolds number and the local porosity estimated from the distance between the bristles. The variations of the permeability are thus deduced for each principal direction and for Reynolds numbers and porosities characteristic for brush seal. The leakage flow rates predicted by the present approach are compared with experimental results from the literature. The results depict also the variations of the pressures, of the local Reynolds number, of the permeability, and of the porosity through the entire brush seal.
Comparing the effect of aperture extension on the peak sidelobe level of sparse arrays
Authors: Rawnaque Ferdousi Sabera , Buck John R.
Published: November 2017

The reduced number of sensors in sparse arrays create high peak sidelobe levels (PSLs). This letter compares the PSLs of minimum redundancy arrays (MRAs), minimum hole arrays (MHAs), and co-prime sensor arrays (CSAs) (conventionally beamformed and product processed) with fully populated uniform linear arrays (ULAs) as a function of aperture using both numerical simulations and experimental data. This letter finds that PSLs of MRAs, MHAs, and conventionally processed CSAs are much higher than the ULA PSL and are largely insensitive to aperture extension. In contrast, CSA product processing decreases the PSL with increasing aperture, eventually matching the ULA PSL.
Finite difference time domain modelling of a point-excited elastic plate radiating into an acoustic cavity
Authors: Ferreira Nuno , Hopkins Carl
Published: November 2017

Finite difference time domain (FDTD) models are developed to solve the vibroacoustic problem of a thin elastic plate undergoing point force excitation and radiating into an acoustic cavity. Vibroacoustic modelling using FDTD can be computationally expensive because structure-borne sound wavespeeds are relatively high and a fine spatial resolution is often required. In this paper a scaling approach is proposed and validated to overcome this problem through modifications to the geometry and physical properties. This allows much larger time steps to be used in the model which significantly reduces the computation time. Additional reductions in computation time are achieved by introducing an alternative approach to model the boundaries between the air and the solid media. Experimental validation is carried out using a thin metal plate inside a small reverberant room. The agreement between FDTD and measurements confirms the validity of both approaches as well as the FDTD implementation of a thin plate as a three-dimensional solid that can support multiple wave types. Below the lowest room mode, there are large spatial variations in the sound field within the cavity due to the radiating plate; this indicates the importance of having a validated FDTD model for low-frequency vibroacoustic problems.
Comparison and analysis of the methods defined by ASTM standard E2235-04, ISO 3382-2-2008, and EASE acoustical modeling software to determine reverberation time RT60 in ordinary rooms
Authors: Montoya Juan C.
Published: November 2017

Determining the reverberation time RT60 is a well known acoustical parameter used by acousticians to characterize acoustically a room. This paper discusses the differences in the results obtained from measuring RT60 using common standards methods defined by ASTM and ISO. It also compares and contrasts those results with acoustical modeling software (EASE) for a small office room, a gymnasium, and a small church sanctuary. A discussion between the procedures utilized, which includes type and location of sound source, position and requirements of the measurement microphones, repeatability of the measurement sample, signal used for the measurement, and frequency range, are attempted in order to evaluate common ground and a relative best practice.
A history of brass bugles in American drum and bugle corps
Authors: Dostal Jack
Published: November 2017

Bugles have long played an important role in American bands and corps, reaching beyond their military origins. As early as the 1920s, competitive drum and bugle corps performed in national competitions sponsored by the American Legion and the Veterans of Foreign Wars. Modern drum corps continue to compete through organizations such as Drum Corps International and Drum Corps Associates. While brass bugles in these competitive drum corps began as military signaling devices, successive modifications made them capable of greater ranges of music. These traditionally valveless, key-of-G bugles evolved to include pistons and rotors, gaining notes beyond a single harmonic series. Instrument sizes were varied to permit pitch ranges from contrabass to soprano. The corresponding music in these shows thus expanded from bugle calls to classical, jazz, and popular genres. This talk will trace the evolution of bugles and their capabilities in American drum corps from their 20th century history through the current day.
Measurement methods for high-performance jet aircraft noise inside a hardened aircraft shelter
Authors: McKinley Richard L. , Wall Alan T. , van Veen Theo A. , van't Hof Jaap
Published: November 2017

High-performance military aircraft regularly operate inside hardened aircraft shelters (HAS). The F-35A aircraft must be certified as safe to operate inside a HAS before it can be deployed and used in such structures worldwide. Acoustic levels at maintainer locations allow for noise dose estimates and regulation of personnel mission support in HASs to mitigate risks of hearing damage. Acoustic levels impinging on the airframe are compared against engineering design limits in order to prevent a reduction in operational lifespan of the aircraft due to acoustic fatigue. The Air Force Research Laboratory, the Royal Netherlands Air Force, and the Dutch national laboratories NLR and TNO collaborated on a set of acoustic measurements for an F-35A operating inside a HAS at Leeuwarden airbase in the Netherlands. The methods, analysis, and qualitative findings of the acoustic measurements are presented here. [Work supported by RNLAF and by the F-35 JPO. Distribution A: Approved for public release; distribution unlimited. Cleared 01/24/2017; JSF17-035.]
Postdoc at NCPA: Explosive growth and entertainment
Authors: Arnott W. P.
Published: November 2017

My postdoctorate from August 1988 to December 1991 at the University of Mississippi and NCPA favorably influenced my career. Thinking back on the cast of characters and the dramatic science being pursued there brings a smile. My main mentors were Dr. James Sabatier, Dr. Richard Raspet, and Dr. Henry Bass. I was involved with theory and experiments for acoustic to seismic coupling; land mine detection; nondestructive measurements of soil properties; and fundamental analysis of Celcor extruded ceramic catalysts as materials for thermoacoustic stacks. We often worked in real-world settings—cotton and soybean fields, and at “Audi Acres” where we used massive low frequency speaker elevated with construction scaffolding and a winch as sound sources. I worked hours with Mike the machinist constructing acoustical resonators and thermoacoustic heat engines. The vibrant social and political scene was something to behold—including early morning jogging in the Faulkner woods, regular basketball games at lunch; visiting politicians and program managers, dancing on tables at the Gin; Friday nights at Dr. Bass’ house; visitors from acoustic institutions around the world; Starnes catfish restaurant.
National Center for Physical Acoustics Aeroacoustics Group
Authors: Ukeiley Lawrence , Murray Nathan E. , Jansen Bernard
Published: November 2017

The Aeroacoustics Group at the National Center for Physical Acoustics (NCPA) was formed in 1999 to open a new avenue of research at the center. Since its inception, the group has strived to study fundamental problems of flow-generated pressure fluctuations (both acoustic and hydrodynamic) and transition them to applied problems predominantly in the aerospace field. Over the years these problems have included vibrations in bodies traveling at supersonic speeds, jet noise associated with supersonic and subsonic exit conditions, and flow over open cavities to name a few. As part of these efforts, the group has added substantial unique infrastructure to the NCPA expanded the capabilities of the research done in house. The presentation will highlight key features of the problems, which have been studied by the group along with the key personnel.
Eye movements and speech prosody in the processing of information structure: An exploratory study in Mandarin Chinese
Authors: Liu Li , Chen Ying , Zhao Xueqin
Published: November 2017

An exploratory study on information processing in Mandarin discourse was carried out using the remote system of eye tracker. A map was designed to display four destination images, four written words of orientations and four values of distance from the map center to the destinations. Participants answered five pre-recorded questions while reading the map on the computer screen in three trials. The experimenter pretended not to have recorded Trial 1 and requested the participants to do the task again in Trial 2. The questions in Trial 3 were recorded with a different gender to indicate a new inquirer. The preliminary results show some major tendencies: (1) gaze points and saccade routes in Trials 2 and 3 were fewer and less complicated compared to Trial 1; (2) fixation duration on the target words was shorter when the information was old than when it was new; (3) duration, F0 and intensity of the target words were reduced in Trials 2 and 3 compared to Trial 1; (4) the duration tended to be longer, the F0 higher but the intensity weaker in Trial 3 than in Trial 2, suggesting a gender difference in the speech, which was also reflected in the eye-movement data.
Phonatory characteristics of ex-vivo aged sheep models
Authors: Döllinger Michael , Gugatschka Markus , Wendler Olaf , Gerstenberger Claus , Sadeghi Hossein , Kniesburges Stefan
Published: November 2017

For humans, voice quality reduces with age. Due to the increasing life span and the increase of the older population, it is necessary to develop new strategies to treat people concerned. Since potential new treatment technologies as functional electrical stimulation have to be first established in animal models, we investigated phonatory characteristics in aged sheep larynges. Ex-vivo dynamic experiments were performed on nine aged sheep larynges providing normative phonatory data. The larynges were analyzed at sustained phonation for varying subglottal pressure levels. Additionally, three different weights were successively attached to the thyroid cartilage to induce pre-stress forces towards the thyroarytenoid muscle and to therefore simulate longitudinal tension of the vocal folds. Laryngeal vibrations, airflow and acoustics were recorded. Afterwards, larynges were analyzed for tissue damage using histological standard methods. Overall, the larynges showed rather asymmetric vibrations and exhibited very soft and pliable vocal fold tissue characteristics. The histological analysis showed (in two cases) minimal damage in form of slight epithelial layer detachments and smaller cracks in the lamina propria. Further and detailed results will be presented. Next, the gathered data and characteristics will be compared to young sheep as well as to aged sheep being treated with functional electrical stimulation.
Autoproducts in refractive waveguides near shadow zones
Authors: Worthmann Brian M. , Dowling David R.
Published: November 2017

The frequency-difference and frequency-sum autoproducts are quadratic products of nonzero-bandwidth frequency-domain acoustic fields at different frequencies but the same spatial location. The autoproducts have been shown to mimic genuine lower- or higher-frequency, out-of-band, acoustic fields within some limitations (Worthmann and Dowling, 2017, JASA 141, 4579–4590). Previous analysis of the autoproducts considered only spatial regions of the environment that were well-ensonified by the in-band acoustic field, which itself is well-described by the ray-approximation. In this presentation, the necessity of this well-ensonified restriction is analyzed by comparing autoproduct fields with their out-of-band analogues in and near acoustic shadow zones created by refraction. The results presented are derived from exact or asymptotic solutions of the Helmholtz equation. The propagation environment chosen for this study is a horizontal, range-independent, stratified, unbounded, truncated-n2-parabolic waveguide, which creates acoustic shadow zones in some regions of the acoustic field. By analyzing the autoproducts near the transition from well-ensonified region to shadow zone, the potentially detrimental effects of diffraction on the autoproducts’ mimicry of out-of-band acoustic fields can be analyzed and quantified. [Sponsored by ONR and NSF.]
The Clarinet in Early New Orleans Jazz: Style, Tone and Function
Authors: White Michael
Published: November 2017

Very different from its sound in classical music, swing, modern jazz or other genres, the authentic New Orleans Jazz clarinet tradition remains among the most distinctive instrumental styles in American music. This program will focus on sound and tonal variety of the clarinet in early jazz in its role as an accompanying or featured instrument in dance ensembles and its high wailing voice in brass bands and jazz funerals. There will be a discussion of the instrument's distinguishing characteristics and tonal possibilities. The high level of diversity of sound among early jazz clarinetists will also be examined as affected by equipment, training and physical characteristics of individual players. Live musical examples will be provided by the Dr. Michael White Quartet. Dr. Michael White is a leading figure in traditional New Orleans jazz and one of only a few to creatively carry on the rich clarinet sound and style of that city. For over two decades he has been the main consultant for traditional jazz for the New Orleans Jazz & Heritage Festival. A relative of several first generation jazz musicians, he has distinguished himself as a jazz historian, writer, producer, and composer. In 2015 he received the Jazz Hero Award from the Jazz Journalists Association. Dr. White earned his PhD in Spanish at Tulane University and currently holds the Charles Keller Endowed Chair in the Humanities at Xavier University of Louisiana.
Infrasound phenomenology, propagation, and detection
Authors: Waxler Roger M.
Published: November 2017

Infrasound is generally understood to refer to acoustic disturbances in the atmosphere in frequency bands below the threshold of human hearing, but above the frequencies at which internal gravity waves propagate. The infrasonic band is nominally taken to be 0.05 Hz up to about 20 Hz. Infrasonic signals tend to be generated by large, violent events and propagate efficiently in sound ducts formed by wind jets and temperature gradients in the middle and upper atmosphere. Infrasonic signals can be detected at very large distances from the source, sometimes even globally. This tutorial will present an overview of the generation of infrasound by both natural and anthropomorphic sources and of the subsequent propagation and detection of infrasonic signals. Two particular sources will be discussed in detail: the signal generated by a large explosion and the so-called microbarom signal generated by colliding ocean waves. Signal propagation through the atmosphere will then be discussed. Available open source infrasound propagation packages and their use will be introduced, the significant atmospheric sound ducts will be identified, and the difficulties inherent in modeling propagation through a dynamic atmosphere will be emphasized. The current state and availability of atmospheric specification will be touched upon. Finally, the use of array processing for the extraction of infrasonic signals from the pressure fluctuations inherent to a turbulent atmosphere will be discussed.
It's All About That Bass, Design of a Showroom for Music, Comedy, and Theater
Authors: Olson Bruce C. , Jaramillo Ana M.
Published: November 2017

An 1800 seat casino showroom was designed to provide “state-of-the-art“ acoustics for superstar country and pop performers, headlining comedians, and big production Broadway musicals. Challenges included a very wide stage, a curved back wall and a client requirement for hidden loudspeakers. This paper will walk you through how these challenges were met while maintaining the high-class look and feel of the room. We will also show the evolution of the sound system design from the initial system through successive upgrades.
Ninety never sounded so good: Guiding an historical auditorium into the 21st century
Authors: Cudequest Brandon , Conant David A.
Published: November 2017

The Sacramento War Memorial Auditorium opened in 1927 with a screening of the silent film, “Old Ironsides.” Over its ninety-year career, the 3500-seat auditorium has hosted everything from Shriners conventions to Shinedown concerts, Ringling Brothers to Rolling Stones, and many more. In its current state, the room is excessively reverberant for amplified music. Heating, ventilation, and air conditioning systems were upgraded during the 1990s, albeit without apparent acoustical input. Street traffic noise is clearly transmitted via acoustically weak windows and stage house doors. McKay Conant Hoover is currently engaged in an acoustical, audiovisual, and theatrical renovation of this historic venue. Importantly, the Auditorium must temporarily accommodate Sacramento's touring Broadway shows, Philharmonic, choral, and ballet performances while their main venue, The Community Center Theater, undergoes a several year-long renovation. This paper will discuss acoustical challenges faced, current findings, and how factors such as ill-conceived pit lifts, historical finishes, limited storage, and lead paint influenced our recommendations.
Passive acoustic monitoring in the Northern Gulf of Mexico using ocean gliders
Authors: Mellinger David K. , Nieukirk Sharon L. , Heimlich Sara L. , Fregosi Selene , Küsel Elizabeth T. , Siderius Martin , Sidorovskaia Natalia
Published: November 2017

Although George Ioup did not use ocean gliders for passive acoustic monitoring, he recognized their value as platforms for PAM and encouraged others to use them. They function well as PAM platforms because (1) they move slowly, minimizing flow noise; (2) they have no propeller or continuously running machinery, minimizing motor noise; (3) they collect acoustic data nearly continuously; (4) they traverse the upper water column every few hours, measuring temperature and salinity as needed for calculating sound speed profiles and enabling accurate modeling of long-range acoustic propagation; (5) they can cover hundreds to thousands of kilometers in distance during a deployment, enabling them to monitor a large area and/or repeatedly monitor a smaller area; and (6) some models can dive to 1000 m, the depth at which some deep-diving cetaceans—sperm and beaked whales, frequent targets of PAM operations—forage and vocalize. Two models of gliders equipped with passive acoustic recording systems were deployed in the Northern Gulf of Mexico in the summers of 2015 and 2017 to study cetacean occurrence and behavior. Here, we summarize the virtues and hazards of glider PAM, and describe acoustic detection and classification of cetaceans in these recordings. [Research supported by GoMRI.]
Airborne electromagnetic profiling in the Gulf of Mexico
Authors: Holladay Kenneth W.
Published: November 2017

First, I will give an overview of the research on Airborne Electromagnetic Profiling (AEM) by the University of New Orleans (UNO) group that included George Ioup. The standard techniques of error correction, calibration, modeling, inverse methods, interpolation, and smoothing were used to convert raw profiler data into meaningful data and useful products. As a part of a NASA EPSCoR project, the group applied layer models to AEM data to measure shallow water bathymetry and water column stratification in the Gulf of Mexico and coastal near surface geomorphology in the Barataria basin of Louisiana. In the second part of the talk, I will sketch the history of the UNO Engineering and Applied Science doctoral program and George Ioup's large role in it.