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Humans use cognitive shortcuts, or heuristics, to quickly assess and respond to situations and data. When applied inappropriately, heuristics have the potential to redirect analysis of available information in consistent ways, creating systematic biases resulting in decision errors. Heuristics have greater effect in high-pressure, high-stakes decisions, particularly when dealing with incomplete information, in other words, daily medical and surgical practice. This article discusses 2 major categories: cognitive biases, which affect how we perceive and interpret clinical data; and implicit biases, which affect how we perceive and respond to other individuals, and also discusses approaches to recognize and alleviate bias effects.

Semiconductor nanowires have been shown to exhibit novel optoelectronic properties with respect to bulk specimens made of the same material. However, if a semiconductor alloy has a miscibility gap in its phase diagram, at equilibrium it will phase separate, leading to deterioration of the aforementioned properties. One way to prevent this separation is to grow the material at low temperatures and therefore to suppress kinetics. Such growth often needs to be followed by high-temperature annealing in order to rid the system of undesirable growth-induced defects. In this study, we propose a method to control phase separation in core-shell nanowires during high temperature annealing by tailoring geometry and strain. Using a phase field model we determined that phase separation in nanowires begins at the free surface and propagates into the bulk. We discovered that including a thin shell around the core delays the phase separation whereas a thick shell suppresses the separation almost entirely.

Jazmurian (or hamun-e Jaz Murian) is a dried lake located in a topographic-low basin in southeast Iran and a major source for high dust emissions under favorable weather conditions. This work examines for the first time the dust activity over the basin by classifying the dust events (DEs, visibility

Objective To describe geographic variation in spending and evaluate regional Medicare expenditures for otolaryngologist services with population- and beneficiary-related factors, physician supply, and hospital system factors. Study Design Cross-sectional study. Methods The average regional expenditures for otolaryngology physician services were defined as the total work relative value units (wRVUs) collected by otolaryngologists in a hospital referral region (HRR) per thousand Medicare beneficiaries in the HRR. A multivariable linear regression model tested associations with regional sociodemographics (age, sex, race, income, education), the physician and hospital bed supply, and the presence of an otolaryngology residency program. Results In 2012, the mean Medicare expenditure for otolaryngology provider services across HRRs was 224 wRVUs per thousand Medicare beneficiaries (standard deviation [SD] 104), ranging from 31 to 604 wRVUs per thousand Medicare beneficiaries. In 2013, the average Medicare expenditures for each HRR was highly correlated with expenditures collected in 2012 (Pearson correlation coefficient .997, P = .0001). Regional Medicare expenditures were independently and positively associated with otolaryngology, medical specialist, and hospital bed supply in the region, and were negatively associated with the supply of primary care physicians and presence of an otolaryngology residency program after adjusting for other factors. The magnitude of associations with physician supply and hospital factors was stronger than any population or Medicare beneficiary factor. Conclusion Wide variations in regional Medicare expenditures for otolaryngology physician services, highly stable over 2 years, were strongly associated with regional health system factors. Changes in health policy for otolaryngology care may require coordination with other physician specialties and integrated hospital systems. Level of Evidence NA. Laryngoscope, 127:1312–1317, 2017

Objectives To describe the deployment of otolaryngologists and evaluate factors associated with the geographic distribution of otolaryngologists in the United States. Study Design Cross-sectional study. Methods The otolaryngology physician supply was defined as the number of otolaryngologists per 100,000 in the hospital referral region (HRR). The otolaryngology physician supply was derived from the American Medical Association Masterfile or from the Medicare Enrollment and Provider Utilization Files. Multiple linear regression tested the association of population, physician, and hospital factors on the supply of Medicare-enrolled otolaryngologists/HRR. Results Two methods of measuring the otolaryngology workforce were moderately correlated across hospital referral regions (Pearson coefficient 0.513, P = .0001); regardless, the supply of otolaryngology providers varies greatly over different geographic regions. Otolaryngologists concentrate in regions with many other physicians, particularly specialist physicians. The otolaryngology supply also increases with regional population income and education levels. Using AMA-derived data, there was no association between the supply of otolaryngologists and staffed acute-care hospital beds and the presence of an otolaryngology residency-training program. In contrast, the supply of otolaryngology providers enrolled in Medicare independently increases for each HRR by 0.8 per 100,000 for each unit increase in supply of hospital beds (P < .0001) and by 0.49 per 100,000 in regions with an otolaryngology residency-training program (P = .006), accounting for all other factors. Conclusion Irrespective of methodology, the supply of otolaryngologists varies widely across geographic regions in the United States. For Medicare beneficiaries, regional hospital factors—including the presence of an otolaryngology residency program—may improve access to otolaryngology services. Level of Evidence N/A. Laryngoscope, 2016

In order to analyze the flow behavior and workability of Ni–42Cu in cast and wrought conditions, hot deformation tests were performed at temperatures and strain rates within the ranges of 900–1150 °C and 0.001–1 s −1 , respectively. Tensile tests showed a “hot ductility trough” at 950 °C for both alloys. The drop in hot ductility was more considerable in the cast alloy because of the sluggish dynamic recrystallization. The hot ductility drop and grain boundary cracking, particularly in the cast alloy, were attributed to the segregation of detrimental atoms to the boundaries. It was shown that the hot ductility of the wrought alloy could be improved with increasing strain rate. It was associated with increasing the fraction of dynamic recrystallization at higher strain rates. This finding corroborated the change in the mechanism of dynamic recrystallization with strain rate. The strain rate sensitivity and instability parameters calculated for the wrought alloy showed that the material is prone to strain localization at low temperatures, i.e., 950–1050 °C, and high strain rates of 0.1 and 1 s −1 . Based on the tensile and compression tests, the best temperature range for a desirable hot workability was introduced as 1050–1150 °C.

Objective The objective is to describe variations in the otolaryngology morbidity and mortality (MM) conference and to compare with other specialties. Design Cross-sectional survey. Setting The setting included otolaryngology departments across the United States and nonotolaryngology medical and surgical departments at 4 academic medical centers. Subjects and Methods Participants were members of a national otolaryngology quality/safety network and nonotolaryngology quality leaders at 4 large academic hospitals. Surveys were administered January 2017. Respondents described MM conference practices, goals, and educational role. Results Twenty-eight of 39 individuals representing 28 institutions completed the otolaryngology survey (72% response rate). Of 197 individuals, 60 (30% response rate) representing 11 surgical and 20 nonsurgical specialties completed the comparison survey. Twenty-seven of 28 otolaryngologists (46 of 60 nonotolaryngologists) worked in academic settings. All otolaryngology programs conducted an MM conference: 54% discussed all adverse events and errors; 32% used standard case selection processes; 70% used structured discussion, usually root cause analysis (64%); and 32% classified harm level. In comparison with other specialties, otolaryngology programs were more likely to discuss all adverse events and errors ( P = .01). Most conferences led to quality projects and intrainstitutional communication: 22% communicated to patients and families; 73% of respondents thought that MM conferences should be standardized or use "best practices." In both surveys, improving patient care was rated the conference's most important function, followed by trainee education and culture change. Patient care and practice-based learning were rated the most relevant Accreditation Council for Graduate Medical Education Core Competencies in both surveys. Conclusions Academic otolaryngology MM practices generally align with other specialties, but specifics vary widely, making collaborative quality improvement challenging. Educational and administrative priorities cross specialties. Most respondents thought that standardization and best practices are worthwhile. Nonacademic practice data are needed.

Semiconductor nanowires, grown heteroepitaxially, have many unique properties compared to heteroepitaxial thin films: e.g., the possibility of lateral relaxation, high surface to volume ratio and lower strain energy. While the onset of plastic deformation in flat thin films has been studied extensively, much less is understood about this phenomenon in the nanowire geometry. Here, we report development of a continuum analytical model that predicts not only the onset of plastic deformation for core-shell structures with anisotropic slip system, but also the evolution of stress and strain fields beyond the initial yield. This is the first analytical elastoplastic study of heteroepitaxial core-shell nanowires. Our model is verified against finite element simulations. To illustrate trends predicted by the model, we choose InGaAs for core-shell system as an example. We find that most energetically favorable positions for formation of the first dislocations in the heterostructure have misorientation of 0, π/2, π, and 3/2π from the principal slip planes in zinc-blend structures. We demonstrate that anisotropy in slip systems of the heterostructure reduces the critical misfit strain. Finally, we find that there is a critical ratio (χ) of shell thickness to core radius that maximizes the thickness of the elastoplastic region. This critical ratio is independent of geometry and depends only on material properties such as elastic moduli and yield strength of the heterostructure.Semiconductor nanowires, grown heteroepitaxially, have many unique properties compared to heteroepitaxial thin films: e.g., the possibility of lateral relaxation, high surface to volume ratio and lower strain energy. While the onset of plastic deformation in flat thin films has been studied extensively, much less is understood about this phenomenon in the nanowire geometry. Here, we report development of a continuum analytical model that predicts not only the onset of plastic deformation for core-shell structures with anisotropic slip system, but also the evolution of stress and strain fields beyond the initial yield. This is the first analytical elastoplastic study of heteroepitaxial core-shell nanowires. Our model is verified against finite element simulations. To illustrate trends predicted by the model, we choose InGaAs for core-shell system as an example. We find that most energetically favorable positions for formation of the first dislocations in the heterostructure have misorientation of 0, π/2, π...

To date, ternary quantum-dot cellular automata (QCA) has been especially investigated and also is being advanced. Nonetheless, it should be possible to make interactions between binary QCA and ternary QCA circuits in order to have a versatile platform of designing. On the other hand, one of the most important concerns in QCA is minimising wire crossings because of low robustness caused by their manufacturing process and operational defects. In this study, a novel ternary-to-binary (and vice versa) converter is introduced firstly and a novel coplanar wire crossing scheme is proposed and presented afterwards. The latter scheme uses both kinds of binary and ternary QCA cells and provides a reliable crossover. Detailed circuit designs and results are presented to show correct functionality of the proposed circuits.

Transdermal patch administration results in a locally high concentration of drug that induce local toxicity, including tumorogenicity. As a worst-case scenario for consequences of repeated application on neoplastic growth, the melanin-binding drug, rasagiline, was used in a transdermal formulation applied directly to a human-derived melanoma to determine the effects on tumor growth.Rasagiline mesylate was administered either orally or transdermally to athymic mice implanted with human melanoma (SKMEL28) to determine the effects on tumor growth and survival. Over a 21-day period, animals were administered daily oral gavage (15 mg/kg) or one or two rasagiline mesylate transdermal patches every 3 days. After the last dose administration, blood samples were collected to confirm drug exposure.All animals from the untreated, vehicle and rasagiline groups survived to the end of the study; however, 7 out of the 10 cisplatin-treated animals died before the end of the study. Rasagiline mesylate dosed either via the oral or transdermal routes had comparable plasma exposure and, unexpectedly, significantly reduced absolute tumor volumes and tumor growth rates in the nude mouse SKMEL28 xenograft model.Transdermal delivery of melanin-binding rasagiline does not increase melanoma growth in the xenograft model. Because rasagiline decreases melanoma growth, it may be candidate for combination therapy for melanoma.

Objectives To describe clinical findings from a multidisciplinary program for children with permanent hearing loss (PHL). Methods Retrospective chart review at a tertiary care children's hospital. Patients: Two hundred patients charts were selected from the population of 260 children with permanent hearing loss presenting between July 2005 and December 2006. Main outcome measures: PHL etiology; radiographic findings; clinical findings by genetics, ophthalmology, developmental pediatrics, speech pathology, and aural rehabilitation. Results Etiology of hearing loss was determined in 60% of subjects. Genetic causes of hearing loss were identified or presumed (positive history of first degree relative with hearing loss) in 27% of the children. Structural ear anomalies were found in 20% of children. Among the 36% of children with CNS imaging, abnormal findings were noted in 32%. There were a high rate of ophthalmological findings (53%) among children seen by ophthalmology (n = 105). Neurodevelopmental evaluations were completed in 58% of subjects and clinically significant findings were noted in 68%. Of the 61% of children who receiving received speech/language evaluations, 77% required intervention. Over half of the 40% of subjects who had an aural rehabilitation evaluation needed therapy. There were not significant differences in rates of findings for children with mild or unilateral hearing loss as compared to children with more severe degrees of hearing loss. Conclusions Interdisciplinary medical evaluation of children with PHL allows for the identification and treatment of clinically significant ophthalmologic, neurodevelopmental, genetic, and speech/language disorders. A high rate of CNS and temporal bone abnormalities were identified. These findings provide an understanding of the importance of considering thorough medical and developmental evaluations among children who are deaf/hard of hearing.

A micromechanical model for prediction of the elastic modulus of polymer/layered silicate nanocomposites was developed based on the conventional Halpin-Tsai model. The model considers near realistic intercalated and exfoliated structures of nanocomposites. The dependence of exfoliation ratio (the ratio of exfoliated filler content to the total filler content) on the filler concentration has been studied from different viewpoints and an exfoliation ratio function has been proposed. The predictions of the proposed model with variable exfoliation ratio functions were compared with the predictions of the same model with constant exfoliation ratio and the predictions of the Halpin-Tsai model using experimentally obtained results. The results of the proposed model with variable exfoliation ratio functions are in very good agreement with experimental data, particularly taking their nonlinearities into account.

Introduction: DNA extraction methods are very important for genetics research and diagnostic tests. In These methods are also important for detecting genetic diseases or in cancers for investigating genetic changes during cancer progression or treatment. Therefore, selection of the best method for DNA extraction from different samples such as bone marrow (BM) or peripheral blood (PB) and their slides is very important. Methods: In the present research, DNA was extracted from 5 different samples including; 1-PB, 2-BM slides stained by Gimsa method, 3-Gimsa stained PB slides from archives, 4-new Gimsa stained PB slides and 5-non stained new PB slides by 3 different methods; salting-out, boiling and phonal chloroform method. In all of the groups, three DNA parameters were investigated; 1-OD (Optimal Density), 2-DNA concentration and 3-Outcome (PCR results). Results: The best DNA quality was achieved by salting-out method (OD=1.74), while the worst quality was by the boiling method (OD

We investigate the molecular beam epitaxy (MBE) growth of GaAs1-xBix film using density functional theory with spin-orbit coupling to understand the growth of this film, especially the mechanisms of Bi incorporation. We study the stable adsorption structures and kinetics of the incident molecules (As₂ molecule, Ga atom, Bi atom, and Bi₂ molecule) on the (2 x 1)-Gasub||Bi surface and a proposed q(1 x 1)-Gasub||AsAs surface has a quasi-(1 x 1) As layer above the Ga-terminated GaAs substrate and a randomly oriented As dimer layer on top. We obtain the desorption and diffusion barriers of the adsorbed molecules and also the reaction barriers of three key processes related to Bi evolution, namely, Bi incorporation, As/Bi exchange, and Bi clustering. The results help explain the experimentally observed dependence of Bi incorporation on the As/Ga ratio and growth temperature. Furthermore, we find that As₂ exchange with Bi of the (2 x 1)-Gasub||Bi surface is a key step controlling the kinetics of the Bi incorporation. Finally, we explore two possible methods to enhance the Bi incorporation, namely, replacing the MBE growth mode from codeposition of all fluxes with a sequential deposition of fluxes and applying asymmetric in-plane strain to the substrate.

Previous studies have shown evidence of cortical reorganization following unilateral sensorineural hearing loss (USNHL). In addition, study participants with right USNHL have shown greater deficits in academic and language performance compared with those with left USNHL. A preliminary functional magnetic resonance imaging investigation was performed on a small cohort of participants, four with left USNHL and four with right USNHL, using the paradigm of listening to random tones. While the participants with left USNHL displayed greater activation in the right superior temporal gyrus, those with right USNHL displayed greater activation in the left inferior frontal area immediately anterior to the superior temporal gyrus. The results provide preliminary evidence of disparate neural circuitry supporting auditory processing in participants with left and right USNHL.

The ongoing childhood obesity epidemic has garnered significant attention among healthcare providers due to its short- and long-term sequelae. Multiple diseases have been associated with obesity, not limited to hypertension, diabetes, and attention deficit hyperactivity disorder. Over the past decade, the relationships between obesity and otologic conditions have been investigated. In this setting, otitis media has remained the focus of research, representing one of the most common pediatric illnesses. Initial studies suggesting a relationship between the two conditions have been supported with epidemiological studies controlling for socioeconomic factors. The purpose of this article is to review our current understanding of the relationship between otitis media and obesity and to discuss the healthcare implications of this association. In addition, several identifiable factors associated with each condition are discussed, as are potential pathophysiologic mechanisms that may help to elucidate the complex and multifactorial relationship between the two disease entities.

Program Description:Quality improvement (QI) activities emphasize systems to prevent or detect inevitable errors by fallible humans. Aside from intentional misconduct or impaired judgment, human errors often are attributed to system factors, deemphasizing the role of individual decision making as a potential cause of error. Convincing data show that cognitive and motivational biases affect how providers collect and apply clinical data. Our purpose is to increase audience awareness of cognitive “traps” in medical decision making. We will discuss illustrative case studies, practical ways to incorporate these concepts into QI and patient safety activities, and uses of “debiasing” and other strategies to improve individual decision making.Educational Objectives:(1) Describe the importance of individual cognitive processes in medical decision making and error and situations in which these processes might be either beneficial or harmful. (2) Describe cognitive processes, heuristics, and biases that play a role ...

(1) To describe the application of a detailed cost-accounting method (time-driven activity-cased costing) to operating room personnel costs, avoiding the proxy use of hospital and provider charges. (2) To model potential cost efficiencies using different staffing models with the case study of outpatient adenotonsillectomy.Prospective cost analysis case study.Tertiary pediatric hospital.All otolaryngology providers and otolaryngology operating room staff at our institution.Time-driven activity-based costing demonstrated precise per-case and per-minute calculation of personnel costs. We identified several areas of unused personnel capacity in a basic staffing model. Per-case personnel costs decreased by 23.2% by allowing a surgeon to run 2 operating rooms, despite doubling all other staff. Further cost reductions up to a total of 26.4% were predicted with additional staffing rearrangements.Time-driven activity-based costing allows detailed understanding of not only personnel costs but also how personnel time is used. This in turn allows testing of alternative staffing models to decrease unused personnel capacity and increase efficiency.

Objective : To identify factors responsible for delays in diagnosis and treatment of pediatric sensorineural hearing impairment (SNHI), and to assess the thoroughness of medical evaluation in these children. Design : Retrospective analysis. Setting : State-supported school for the deaf. Patients and other participants : 291 children with SNHI, the vast majority of whom are profoundly hearing impaired. Data were collected from the school's database, individual student records, and a parental questionnaire. Main outcome measures : (1) The age of diagnosis and treatment of SNHI; (2) factors leading to a delay in diagnosis; (3) current medical evaluations used to determine the etiology of SNHI; and (4) the level of parental satisfaction with the evaluation process. Results : Many children with SNHI experience delays in diagnosis from the time of first suspicion of hearing loss. Children with a risk factor for SNHI are diagnosed no earlier than children without a risk factor. Caucasian children are diagnosed significantly earlier than either Black or Hispanic children, regardless of socioeconomic status. Inconsistent medical evaluation ensues following the diagnosis of SNHI, and parental satisfaction with this process is low. Conclusions : The average age of diagnosis of SNHI remains unacceptably high. There exists a need to enhance physician awareness of childhood deafness and to develop guidelines for the medical evaluation in cases of pediatric SNHI. Lastly, the importance of parental concern regarding a child's hearing or language development must be re-emphasized.

Pressure equalization tube (PET) placement is the most common surgical procedure performed during childhood. Current guidelines recommend more prompt management of children with otitis media with effusion who are at greater risk for speech-language and developmental problems. This study was designed to examine risk factors for continued post-PET hearing loss in a large pediatric clinical sample.Retrospective analysis using the electronic medical record.Tertiary care children's hospital.Pediatric patients undergoing PET placement between January 2009 and October 2012 who had audiometric tests.Demographics, patient diagnoses, and hearing loss information were extracted. Multivariate binary logistic regression models were used to identify associations between patient-specific characteristics and the presence of hearing loss.In total, 3949 children with 4598 audiology visits were included (2357 males and 1592 females; mean age, 3.3 years), and 1272 preoperative and 3329 postoperative audiograms were performed. Using multivariate modeling, the only variable significantly associated with preoperative hearing loss was low tympanometric static acoustic admittance. Postoperative hearing loss was positively associated with patient age, preoperative hearing loss, lower tympanometric equivalent canal volumes, and Down syndrome. Other factors, including cranial/facial anomalies, low birth weight or prematurity, allergies, and asthma, were not determined to be risk factors for hearing loss.Our results support hearing testing to identify candidates for PET surgery and to determine treatment effectiveness after surgery, since hearing loss cannot be predicted on the basis of risk or demographic factors. These data have important preoperative counseling and postoperative management implications.

Objectives:Pressure equalization tube (PET) placement is the most common surgical procedure performed during childhood. Current Academy guidelines recommend more aggressive management of children with otitis media with effusion (OME) who are at greater risk for speech-language and developmental problems. This study was designed to examine risk factors for continued hearing loss following PET placement in children with chronic OME. A large clinical sample ascertained through electronic medical records is used.Methods:All pediatric patients undergoing PET-placement between January 2009 andOctober 2012 at a tertiary-care children’s hospital who had audiometric tests were included. Demographics and patient diagnoses (craniofacial anomalies, allergies, prematurity, developmental delay, and speech-language delay) were extracted. A multivariate regression model was used to identify an association between patient-specific characteristics and the presence of pre- or postoperative hearing loss.Results:4083 children...

Natural Organic Matter (NOM) is a non-uniform mixture of organic compounds that enter water after synthesis of plants, animals, etc. Among the organic matters in natural waters, humic substances which usually exist as solutions have allocated a major portion to themselves and in addition to giving taste, color and odor to the water, they can intervene in the oxidization and removal of heavy metals such as arsenic, iron and manganese. Also, the natural organic precursors of disinfection by-products have been recognized as toxic or carcinogenic substances. The coagulation process is optimized as the most common system of water treatment in Iran for removing turbidity of water. This process is capable of removing the natural organic matter but the conditions for the removal of turbidity are constantly not identical with the optimum conditions for removing the NOM. Therefore, where NOM is the main pollutant, the traetment process should be optimized for removing NOM. Therefore, where NOM is the main pollutant, the traetment process should be optimized for removing NOM. After doing the common treatment, the water of Kardeh dam of Mashhad is used as drinking water of the city of Mashhad. By doing the water analysis experiments, the amounts of natural organic matter in the exiting water from water treatment plant was observed at 5 mg/l which is much higher than the world standards of drinking water. In this research the optimum conditions for the removal of NOM from drinking water of Kardeh dam have been examined. The experiments have been conducted at the laboratory scale and by Jar Test Device by different doses of two coagulants of alum and ferric chloride at various pH of water. It is concluded that these coagulation process by two coagulants remove NOM from drinking water and bring it to standards of US Environmental Protection Agency and World Health Organization. Keywords : advanced coagulation; natural organic matter; drinking water; city of Mashhad.

Program Description: Cultivation of career advancement of young physicians in private or academic practice requires significant investment of financial resources as well as time investment on the part of their senior mentors. As more women become otolaryngologists, gender differences that affect women’s expectations and communication style may lead to misunderstandings that interfere with career development. Understanding the impact of gender differences in the work place is important to strengthen physician practices by improving workforce retention and diversity. Over the past 30 years much research has emerged describing how gender affects overall career advancement. Differences in the ways that men and women see the world, their propensity to negotiate for resources, and the existence of cultural biases may significantly impact career advancement, especially for those aspiring to leadership positions. An overview of: 1) the current status of women in otolaryngology, 2) effective mentorship, and 3) gender differences that may create barriers or serve as strengths for women will be provided during the first half of this miniseminar. The program will conclude with an interactive panel whose members will share their insights regarding career development and mentorship.

Donepezil hydrochloride is a reversible acetyl cholinesterase inhibitor approved for Alzheimer disease treatment. As an alternate therapy, a donepezil hydrochloride transdermal patch is in development. Recommended nonclinical safety studies include a 3-month Good Laboratory Practice (GLP) dose-range finding (DRF) study prior to conducting the 2-year dermal carcinogenicity study in rats. Demonstration of systemic exposure is necessary to interpret the in vivo data. Previous nonclinical reports supporting oral dosing have utilized liquid chromatography tandem mass spectrometry (LC/MS/MS) to quantify donepezil concentrations in plasma. Smaller species with limited blood volumes do not allow serial sampling to derive the full pharmacokinetic profile from a single animal. Therefore, the option of another analytical method requiring decreased sample volumes is desirable as it would decrease the required number of animals while obtaining the complete profile. The dried blood spot (DBS) technique allows drug level measurement from a few microliters; however, the method is still not widely utilized in GLP studies. Because donepezil plasma levels are known by the oral route, DBS was used to bridge the previous oral data and to support a 13-week GLP DRF study for repeated topical application in rats, comparing oral administration with 4 topical formulations. The DBS method was validated and demonstrated robustness and reproducibility for application to the DRF study. The assay results were comparable to a previously reported plasma LC/MS/MS assay-derived pharmacokinetic profile and provided justification for selection of the topical formulation and dose levels for the subsequent dermal carcinogenicity study.

Objective Temporal bone imaging in children has several inherent limitations. Computed tomography has the disadvantage of ionizing radiation, possible sedation, cost and accessibility. Magnetic resonance imaging has most of these disadvantages, with the exception of radiation, and provides bone images of limited resolution. Recent advances in ultrasound have led to its increased application in numerous medical fields. The purpose of this study was to investigate the ability of four-dimensional ultrasound (4DUS) to image middle ear ossicles in vitro and determine if this technology should be adapted for future clinical use. Methods Thirty cadaveric ossicles (10 malleus, 10 incus, and 10 stapes) were randomized and measured by two evaluators under a microscope. The ossicles were then immersed in a cold water bath and imaged, randomized, and measured using four-dimensional ultrasound by the same two evaluators. A separate cadaveric temporal bone, modified to allow the ultrasound probe to rest on the tympanic membrane, was imaged to visualize the ossicles in situ and evaluate whether or not the tympanic membrane and malleus would impede visualization of more medial structures. Results Microscopic measurements were: malleus (h = 8.0 mm ± 0.32, w = 2.7 mm ± 0.20 ), incus (h = 6.8 mm ± 0.41, w = 5.3 mm ± 0.46 ), stapes (h = 3.5 mm ± 0.34, w = 2.4 mm ± 0.17 ). Inter-rater reliability was 0.8. Measurements were in agreement with previously published values. Ultrasound measurements were: malleus (h = 8.0 mm ± 0.51, w = 2.9 mm ± 0.27 ), incus (h = 6.8 mm ± 0.49, w = 5.5 mm ± 0.42 ), stapes (h = 3.6 mm ± 0.41, w = 2.5 mm ± 0.19 ). Inter-rater reliability was 0.7. Mean intra-class correlation coefficient for microscopic and ultrasound measurements was 0.7. Images of the ossicular chain in continuity in the temporal bone specimen were not as clear as images of individual ossicles that were disarticulated and imaged under water. Conclusions 4DUS provides reasonable images of ossicles disarticulated and mounted in underwater medium. However, images of the intact ossicular chain in a modified cadaveric temporal bone were not as clear, making interpretation difficult. Further investigation into the development of a thinner ultrasound probe that can pass through the external auditory canal and into overcoming limitations of air in the middle ear cleft are warranted. This could allow for a clinically relevant, faster, lower cost and lower risk alternative to current imaging techniques.

Objective To measure the quality of outpatient surgery in an ambulatory surgery center (ASC) compared to a hospital-based facility (HBF) in a multidimensional manner. Study Design Cross-sectional survey based on chart review. Setting Pediatric academic health center. Subjects and Methods A total of 486 cases were reviewed. Procedures were performed at either an ASC (n = 275) or an HBF (n = 211). Cases comprised four procedure types: ventilation tube insertion (ASC, n = 126; HBF, n = 108), dental rehabilitation (ASC, n = 89; HBF, n = 58), adenotonsillectomy (ASC, n = 37; HBF, n = 34), and ventilation tube insertion/adenoidectomy (ASC, n = 23; HBF, n = 11). Measures were developed for five categories: safety, patient-centeredness, timeliness, efficiency, and equitability. Performance was compared between facilities. Results The ASC had no unexpected safety events (0/275) compared to nine events (9/211) at the HBF. Tonsil bleed rates were 0 percent (0/37) at the ASC compared to 5.9 percent (2/34) at the HBF. Patient satisfaction was similar between facilities (ASC, n = 64; HBF, n = 35). Differences in timeliness approached 30 percent. A total of 77 percent of ASC cases finished within the scheduled time compared to 38 percent at the HBF. Total charges were 12 to 23 percent less at the ASC. Patients treated at the ASC generally lived in wealthier neighborhoods. Conclusion Performance at the ASC generally exceeded that at the HBF. Future research should investigate how perioperative processes result in these quality differences. Health policy implications are discussed.

To correlate genetic and audiometric findings with a detailed radiologic analysis of the temporal bone in patients with enlarged vestibular aqueduct (EVA) to ascertain the contribution of SLC26A4 gene mutations to this phenotype.A retrospective review of patients with EVA identified in a database of pediatric hearing-impaired patients.A tertiary care pediatric referral center.Seventy-one children with EVA and screening results for SLC26A4 mutations.Genetic screening results, audiometric thresholds, and radiographic temporal bone measurements.Seventy-one children with EVA were screened for SLC26A4 mutations. Mutations were found in 27% of children overall, while only 8% had biallelic mutations. The mean initial pure-tone average (PTA) was 59 dB; the mean final PTA was 67 dB. A bilateral EVA was found in 48 (67%) of the children; a unilateral EVA was found in 23 (33%). Progressive hearing loss (in at least 1 ear) was seen in 29 (41%) of the patients. The strongest genotype-phenotype interaction was seen in children with a bilateral EVA. Among children with SLC26A4 mutations, there was a significantly wider vestibular aqueduct at the midpoint and a wider vestibule width (P.05) than in children without the mutation. Among patients with a bilateral EVA, children with any SLC26A4 mutation were more likely to have a more severe final PTA (64 dB vs 32 dB), larger midpoint measurement (2.1 vs 1.1 mm), and larger operculum measurement (3.0 vs 2.0 mm) than those without the mutation in their better-hearing ear (P.05).In a population of pediatric patients with an EVA and hearing loss, SLC26A4 mutations are a contributor to the phenotype. Our data suggest that other genetic factors also have important contributions to this phenotype. The presence of an abnormal SLC26A4 allele, even in the heterozygous state, was associated with greater enlargement of the vestibular aqueduct, abnormal development of the vestibule, and possibly a stable hearing outcome.

Objective The study goal was to determine the prevalence and clinical significance of a large vestibular aqueduct (LVA) in children with sensorineural hearing loss (SNHL). Study Design and Setting We conducted a retrospective review of a pediatric SNHL database. One hundred seven children with SNHL were selected and their radiographic and audiometric studies were evaluated. Radiographic comparisons were made to a group of children without SNHL. Results A vestibular aqueduct (VA) larger than the 95th percentile of controls was present in 32% of children with SNHL. Progressive SNHL was more likely to occur in ears with an LVA and the rate of progressive hearing loss was greater than in ears without an LVA. The risk of progressive SNHL increased with increasing VA size as determined by logistic regression analysis. Conclusions An LVA is defined as one that is ≥2 mm at the operculum and/or ≥1 mm at the midpoint in children with nonsyndromic SNHL. An LVA appears to be more common than previously reported in children with SNHL. A linear relationship is observed between VA width and progressive SNHL. Significance The finding of an LVA in children with SNHL provides diagnostic as well as prognostic information.

This paper describes a real-time implementation of a variable rate baseband speech coding algorithm. The implementation is achieved using the Speech Command System (SCS) option available with the Texas Instruments Professional Computer (TIPC). The SCS consists of a peripheral speech board and related interface software. The central processor on the peripheral speech board is TI's new signal processing microcomputer TMS32010. The implementation works real-time with an average bit rate of the 9600 bits/sec.

Minimal roundoff noise IIR digital filters require (n+1)2multiplies per output sample for an nth order filter. By optimizing second-order sections which are then parelleled or cascaded, one can reduce this to approximately 4n multiplies per output. This compares to approximately 3n multiplies for the direct form. This paper presents explicit design equation and noise performance equations for low roundoff noise, second-order filters with fewer multipliers than optimal forms. These structures are a compromise between direct forms (minimal number of multipliers) and minimal roundoff noise structures.

This paper examines a technique for reducing the effect of pitch-incongruence or harmonic offset in baseband speech coding of high pitched voices. The proposed method employs a variable-width baseband coding scheme. A nominal baseband width can be specified. Actual width of the baseband is determined in every frame to be a number closest to the nominal width that contains an integer number of multiples of fundamental pitch frequency. When baseband is copied up to higher bands, phase of the copied up bands must be frequency-adjusted to form a consistent overall phase function for that frame. This ensures more appropriate addition of harmonics to generate pitch pulses at desired positions in the regenerated residual signal. A method for making such adjustment to phase of the copied up bands is explored and its promises and limitations are discussed.

The computation of the (noncyclic) convolution of two sequences occurs in a variety of digital signal processing applications, e.g., correlation and linear filtering. Direct evaluation involving sequences of length N requires N multiplications and (N-1)2additions. A std. approach for large N uses the FFT to reduce the number of computations. This requires that one append a guard band of N zeros. Recently new convolution algorithms have been proposed based on rectangular transform techniques [1]. While these algorithms are highly efficient they are not easily implemented. The objective of this work is the development of a unified theory for multifactor convolution algorithms which are efficient and easily implemented. An algorithm has been developed which is a composition of a number of prime factor algorithms. If N = n_{1}^{k_{1}}n_{2}^{k_{2}} ... n_{r}^{k_{r}} (where the n i are prime and the k i are integers) is a product of many factors, this new algorithm can result in a significant savings. Computational comparisons are given for these new algorithms against the most efficient FFT methods as described in [2]. It is shown that the algorithms in [3] for N=2 k are a special case of the multifactor algorithms.

Good digital filter realizations for hardware implementation in narrowband filtering applications should have low roundoff noise, low coefficient sensitivity, and freedom from overflow oscillations. The hardware implementations presented here incorporate the above properties into a highly modular structure which can perform computations in pipeline fashion. That is, after an initial delay an output sample is obtained for each input sample. The realization and implementations discussed here contain more multipliers than direct form realizations. However, by using shorter word lengths because of their increased performance and distributed arithmetic implementations (instead of multiplier structures) these implementations can have less total hardware complexity.