A Diagonal‐Steering‐Based Binaural Beamforming Algorithm Incorporating a Diagonal Speech Localizer for Persons With Bilateral Hearing Impairment

Previously suggested diagonal‐steering algorithms for binaural hearing support devices have commonly assumed that the direction of the speech signal is known in advance, which is not always the case in many real circumstances. In this study, a new diagonal‐steering‐based binaural speech localization (BSL) algorithm is proposed, and the performances of the BSL algorithm and the binaural beamforming algorithm, which integrates the BSL and diagonal‐steering algorithms, were evaluated using actual speech‐in‐noise signals in several simulated listening scenarios. Testing sounds were recorded in a KEMAR mannequin setup and two objective indices, improvements in signal‐to‐noise ratio (SNR_i) and segmental SNR (segSNR_i), were utilized for performance evaluation. Experimental results demonstrated that the accuracy of the BSL was in the 90–100% range when input SNR was ?10 to +5 dB range. The average differences between the γ‐adjusted and γ‐fixed diagonal‐steering algorithms (for ?15 to +5 dB input SNR) in the talking in the restaurant scenario were 0.203–0.937 dB for SNR_i and 0.052–0.437 dB for segSNR_i, and in the listening while car driving scenario, the differences were 0.387–0.835 dB for SNR_i and 0.259–1.175 dB for segSNR_i. In addition, the average difference between the BSL‐turned‐on and the BSL‐turned‐off cases for the binaural beamforming algorithm in the listening while car driving scenario was 1.631–4.246 dB for SNR_i and 0.574–2.784 dB for segSNR_i. In all testing conditions, the γ‐adjusted diagonal‐steering and BSL algorithm improved the values of the indices more than the conventional algorithms. The binaural beamforming algorithm, which integrates the proposed BSL and diagonal‐steering algorithm, is expected to improve the performance of the binaural hearing support devices in noisy situations.     

A New Asymmetric Directional Microphone Algorithm With Automatic Mode‐Switching Ability for Binaural Hearing Support Devices

For hearing support devices, it is important to minimize the negative effect of ambient noises for speech recognition but also, at the same time, supply natural ambient sounds to the hearing‐impaired person. However, conventional fixed bilateral asymmetric directional microphone (DM) algorithms cannot perform in such a way when the DM‐mode device and a dominant noise (DN) source are placed on the same lateral hemisphere. In this study, a new binaural asymmetric DM algorithm that can overcome the defects of conventional algorithms is proposed. The proposed algorithm can estimate the position of a specific DN in the 90°–270° range and switch directional‐ and omnidirectional‐mode devices automatically if the DM‐mode device and the DN are placed in opposite lateral hemispheres. Computer simulation and KEMAR mannequin recording tests demonstrated that the performance of the conventional algorithm deteriorated when the DM‐mode device and the DN were placed in the opposite hemisphere; in contrast, the performance of the proposed algorithm was consistently maintained regardless of directional variations in the DN. Based on these experimental results, the proposed algorithm may be able to improve speech quality and intelligibility for hearing‐impaired persons who have similar degrees of hearing impairment in both ears.     

An Environment‐Adaptive Management Algorithm for Hearing‐Support Devices Incorporating Listening Situation and Noise Type Classifiers

In order to provide more consistent sound intelligibility for the hearing‐impaired person, regardless of environment, it is necessary to adjust the setting of the hearing‐support (HS) device to accommodate various environmental circumstances. In this study, a fully automatic HS device management algorithm that can adapt to various environmental situations is proposed; it is composed of a listening‐situation classifier, a noise‐type classifier, an adaptive noise‐reduction algorithm, and a management algorithm that can selectively turn on/off one or more of the three basic algorithms—beamforming, noise‐reduction, and feedback cancellation—and can also adjust internal gains and parameters of the wide‐dynamic‐range compression (WDRC) and noise‐reduction (NR) algorithms in accordance with variations in environmental situations. Experimental results demonstrated that the implemented algorithms can classify both listening situation and ambient noise type situations with high accuracies (92.8–96.4% and 90.9–99.4%, respectively), and the gains and parameters of the WDRC and NR algorithms were successfully adjusted according to variations in environmental situation. The average values of signal‐to‐noise ratio (SNR), frequency‐weighted segmental SNR, Perceptual Evaluation of Speech Quality, and mean opinion test scores of 10 normal‐hearing volunteers of the adaptive multiband spectral subtraction (MBSS) algorithm were improved by 1.74 dB, 2.11 dB, 0.49, and 0.68, respectively, compared to the conventional fixed‐parameter MBSS algorithm. These results indicate that the proposed environment‐adaptive management algorithm can be applied to HS devices to improve sound intelligibility for hearing‐impaired individuals in various acoustic environments.     

An Eye‐Blinking‐Based Beamforming Control Protocol for Hearing Aid Users With Neurological Motor Disease or Limb Amputation

For hearing‐impaired individuals with neurological motor deficits or finger/arm amputation due to accident or disease, hearing aid adjustment using a conventional finger manipulation‐based remote controller is unavailable, and a more dedicated, hands‐free alternative is required. In this study, we propose an eye‐blinking‐based beamforming control scheme for hearing aid users. Three electroencephalogram signals measured around the ears were utilized to detect eye‐blinking patterns based on a three‐layer artificial neural network. The performance of the proposed control scheme was evaluated by both subjective experiments and objective index comparison tests in simulated situations. Experimental results from the subjective test demonstrated that without the pretraining phase, the accuracy and latency time were 68.57 ± 18.50% and 10.06 ± 0.94 s, respectively; in contrast, after the pretraining phase, both the accuracy and latency time were improved to 91.00 ± 4.69% and 8.60 ± 1.05 s, respectively. In index comparison tests, the proposed control scheme exhibited improvements in the signal‐to‐noise ratio (SNR) as well as the segmental SNR in all tested situations, as compared to a conventional forward‐focusing beamforming algorithm. We believe that the proposed control scheme provides a novel, hands‐free way in which to control the operation of hearing aids for hearing‐impaired patients with additional motor deficits or amputation.     

Linear quadratic regulation for discrete‐time systems with multiplicative noise and multiple input delays

This paper is concerned with the optimal linear quadratic regulation problem for discrete‐time systems with state and control dependent noises and multiple delays in the input. We show that the problem admits a unique solution if and only if a sequence of matrices, which are determined by coupled difference equations developed in this paper, are positive definite. Under this condition, the optimal feedback controller and the optimal cost are presented via some coupled difference equations. Our approach is based on the stochastic maximum principle. The key technique is to establish relations between the costate and the state. Copyright © 2016 John Wiley & Sons, Ltd.     

The Long‐Term Follow‐up and Support for Living Organ Donors: A Center‐Based Initiative Founded on Developing a Community of Living Donors

Transplant professionals recognize that the long‐term follow‐up of living organ donors is a priority, yet there has been no implemented solution to this problem. This critical gap is essential, because the transplant field is now emphasizing living donation as a means to address the organ shortage. We detail our living donor initiative, which sets several priorities we recognize as fundamental to persons who have donated organs at our transplant center. This intervention attempts to mitigate the donor and center factors that are known to contribute to the lack of long‐term follow‐up. Beyond that, our goals are aimed at providing ongoing engagement, wellness, clinical data accrual, laboratory follow‐up, and social support for our living donors, in continuity. Our ultimate goal is to nurture the development of local living donor community networks by providing social engagement for current and past donors, which also serves as a platform for greater population education on the societal importance of living donation. This initiative is based on joint recognition by our transplant team and our hospital leadership that supporting the long‐term welfare of living donors is essential to accomplishing the goal of expanding living donor transplantation. The transplant team and hospital missions are aligned, and both contribute resources to the initiative.     

Safety and efficacy of cryolipolysis for non‐invasive reduction of submental fat

Background and Objectives

Cryolipolysis has previously received FDA clearance for fat reduction in the abdomen, flanks, and thighs. There is also interest in small volume fat reduction for areas such as the chin, knees, and axilla. This article reports the results of a cryolipolysis pivotal IDE study for reduction of submental fullness.

Study Design/Material and Methods

A prototype small volume vacuum applicator (CoolMini applicator, CoolSculpting System, ZELTIQ Aesthetics) was used to treat 60 subjects in the submental area. At each treatment visit, a single treatment cycle was delivered at ?10°C for 60 minutes, the same temperature and duration used in current commercially‐available cryolipolysis vacuum applicators. At the investigator's discretion, an optional second treatment was delivered 6 weeks after the initial treatment. The primary efficacy endpoint was 80% correct identification of baseline photographs by independent physician review. The primary safety endpoint was monitoring incidence of device‐ and/or procedure‐related serious adverse events. Secondary endpoints included assessment of fat layer thickness by ultrasound and subject satisfaction surveys administered 12 weeks after final cryolipolysis treatment.

Results

Independent photo review from 3 blinded physicians found 91% correct identification of baseline clinical photographs. Ultrasound data indicated mean fat layer reduction of 2.0 mm. Patient questionnaires revealed 83% of subjects were satisfied, 80% would recommend submental cryolipolysis to a friend, 77% reported visible fat reduction, 77% felt that their appearance improved following the treatment, and 76% found the procedure to be comfortable. No device‐ or procedure‐related serious adverse events were reported.

Conclusion

The results of this clinical evaluation of 60 patients treated in a pivotal IDE study demonstrate that submental fat can be reduced safely and effectively with a small volume cryolipolysis applicator. Patient surveys revealed that submental cryolipolysis was well‐tolerated, produced visible improvement in the neck contour, and generated high patient satisfaction. These study results led to FDA clearance of cryolipolysis for submental fat treatment. Lasers Surg. Med. 48:3–13, 2016. © 2015 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

     

Comparison of Perfusion Quality in Hollow‐Fiber Membrane Oxygenators for Neonatal Extracorporeal Life Support

Perfusion quality is an important issue in extracorporeal life support (ECLS); without adequate perfusion of the brain and other vital organs, multiorgan dysfunction and other deficits can result. The authors tested three different pediatric oxygenators (Medos Hilite 800 LT, Medtronic Minimax Plus, and Capiox Baby RX) to determine which gives the highest quality of perfusion at flow rates of 400, 600, and 800 mL/min using human blood (36°C, 40% hematocrit) under both nonpulsatile and pulsatile flow conditions. Clinically identical equipment and a pseudo‐patient were used to mimic operating conditions during neonatal ECLS. Traditionally, the postoxygenator surplus hemodynamic energy value (SHE_post, extra energy obtained through pulsatile flow) is the one relied upon to give a qualitative determination of the amount of perfusion in the patient; the authors also examined SHE retention through the membrane, as well as the contribution of SHE_post to the postoxygenator total hemodynamic energy (THE_post). At each experimental condition, pulsatile flow outperformed nonpulsatile flow for all factors contributing to perfusion quality: the SHE_post values for pulsatile flow were 4.6–7.6 times greater than for nonpulsatile flow, while the THE_post remained nearly constant for pulsatile versus nonpulsatile flow. For both pulsatile and nonpulsatile flow, the Capiox Baby RX oxygenator was found to deliver the highest quality of perfusion, while the Minimax Plus oxygenator delivered the least perfusion. It is the authors' recommendation that the Baby RX oxygenator running under pulsatile flow conditions be used for pediatric ECLS, but further studies need to be done in order to establish its effectiveness beyond the FDA‐approved time span.     

The Hemodynamic Effect of the Support Mode for the Intra‐Aorta Pump on the Cardiovascular System

Intra‐aorta pump is a novel rotary ventricular assist device. Because of the special structure and connection with the native heart, the hemodynamic effect of support mode of this pump on the cardiovascular system is not clear. In this work, three support modes, including “constant speed” mode, “co‐pulse” mode, and “counter‐pulse” mode, have been designed for the intra‐aorta pump to evaluate the hemodynamic effect of different support modes on the cardiovascular system. Simulation results demonstrate that that both “co‐pulse” mode and “counter‐pulse” mode can achieve better unloading performance than “constant speed” mode. The intra‐aorta pump controlled by “co‐pulse” mode is beneficial for improving coronary flow. Moreover, the external work, which is defined as the product of left ventricular pressure and cardiac output, under “co‐pulse” mode is the minimum of the three support modes (0.783 w vs. 0.615 w vs. 0.702 w). The pulsatility ratio, defined as the ratio of the peak‐to‐peak value of arterial pressure (AP) to the mean arterial pressure value, under “co‐pulse” mode is the maximum of the three modes (24% vs. 32.8% vs. 23.7%). The equivalent afterload value, which is the ratio of pulsatile pressure at the pump inflow and pulsatile pump flow, is larger than other support modes (0.596 mm Hg.s/mL vs. 0.9704 mm Hg.s/mL vs. 0.55 mm Hg.s/mL). In brief, the intra‐aorta pump under “co‐pulse” mode support is beneficial for improving myocardial perfusion and restoring pulsatility of AP, while “counter‐pulse” mode is beneficial to the perfusion of vital organs.     

The Lateral Inframammary Fold Incision for Nipple‐Sparing Mastectomy: Outcomes from Over 50 Immediate Implant‐Based Breast Reconstructions

Nipple‐sparing mastectomy (NSM) as a therapeutic or prophylactic procedure for breast cancer is rapidly gaining popularity as the literature continues to support it safety. The lateral inframammary fold (IMF) approach provides adequate exposure and eliminates visible scars on the anterior surface of the breast, making this incision cosmetically superior to radial or periareolar approaches. We reviewed 55 consecutive NSMs performed through a lateral IMF incision with immediate implant‐based reconstruction, with or without tissue expansion, between June 2008 and June 2011. Prior to incision, breasts were lightly infiltrated with dilute anesthetic solution with epinephrine. Sharp dissection, rather than electrocautery, was used as much as possible to minimize thermal injury to the mastectomy flap. When indicated, acellular dermal matrix was placed as an inferolateral sling. Subsequent fat grafting to correct contour deformities was performed in select patients. Three‐dimensional (3D) photographs assessed changes in volume, antero‐posterior projection, and ptosis. Mean patient age was 46 years, and mean follow‐up time was 12 months. Twelve mastectomies (22%) were therapeutic, and the remaining 43 (78%) were prophylactic. Seven of the nine sentinel lymph node biopsies (including one axillary dissection) (78%) were performed through the lateral IMF incision without the need for a counter‐incision. Acellular dermal matrix was used in 34 (62%) breasts. Average permanent implant volume was 416 cc (range 176–750 cc), and average fat grafting volume was 86 cc (range 10–177 cc). In one patient a positive intraoperative subareolar biopsy necessitated resection of the nipple‐areola complex (NAC), and in two other patients NAC resection was performed at a subsequent procedure based on the final pathology report. Mastectomy flap necrosis, requiring operative debridement, occurred in two breasts (4%), both in the same patient. One of these breasts required a salvage latissimus dorsi myocutaneous flap to complete the reconstruction. Three nipples (6%) required office debridement for partial necrosis and operative reconstruction later. No patient had complete nipple necrosis. No statistically significant differences existed between therapeutic and prophylactic mastectomies for developing partial skin and/or nipple necrosis (p = 0.35). Three episodes (5%) of cellulitis occurred, which responded to antibiotics without the need for explantation. Morphological outcomes using 3D scan measurements showed reconstructed breasts were larger, more projected, and less ptotic than the preoperative breasts (196 versus 248 cc, 80 versus 90 mm, 146 versus 134 mm, p < 0.01 for each parameter). Excellent results can be achieved with immediate implant‐based reconstruction of NSM through a lateral IMF incision. NAC survival is reliable, and complication rates are low. blechmanplasticsurgery.com     

Evaluation of the role of dexamethasone in decreasing early recurrence of intussusception: Using ultrasound‐guided saline enema for reduction

Aim: Intussusception is the most common abdominal emergency during early childhood. The current initial management by contrast enema or pneumatic reduction under fluoroscopy carries the risk of radiation. In case of recurrence, the repeated attempts for another reduction will also increase this risk, in addition to other risks of operative reduction, if needed. The aim of this study was to evaluate the effectiveness of ultrasound‐guided saline enema reduction (USGSER) in the diagnosis and treatment of intussusception, and to assess the value of using dexamethasone injection in preventing or minimizing the frequency of recurrence. Patients and methods: The study included 75 cases with intussusception presented from August 2006 until July 2010 to Assiut University Children's Hospital. They were randomly classified into two groups: group A (GA; 40 cases) received three doses of i.m. dexamethasone, once before starting reduction and every 8 h thereafter; group B (GB; 35 cases) did not receive dexamethasone. The success, failure and recurrence rates after USGSER in the two groups were reported. Results: Ultrasonography was diagnostic in all cases. Successful USGSER was obtained in 33 of 40 cases in GA, and in 27 of 35 cases in GB. The recurrence of intussusception was encountered in one case of GA, and in five cases of GB postreduction; all were treated successfully by USGSER. Failure of USGSER with subsequent laparotomy occurred in 15 cases; (7 from GA, and 8 from GB) where manual reduction could be obtained in nine cases, while resection anastomosis was necessary in six cases. Conclusion: USGSER is a safe, easy and cost‐effective modality of treatment for intussusceptions, without the risk of radiation. Dexamethasone might help in decreasing the frequency of recurrence.     

Patterns of Care in the Administration of Neo‐adjuvant Chemotherapy for Breast Cancer. A Population‐Based Study

Neo‐adjuvant chemotherapy (NAC) is used to facilitate radical surgery for initially irresectable or locally advanced breast cancer. The indication for NAC has been extended to clinically node negative (cN0) patients in whom adjuvant systemic therapy is foreseen. A population‐based study was conducted to evaluate the increasing use of NAC, breast conserving surgery (BCS) after NAC and timing of the sentinel node biopsy (SNB). All female breast cancer patients, treated in 10 hospitals in the Eindhoven Cancer Registry area in the Netherlands between January 2003 and June 2012 were included (N = 18,427). In total, 1,402 patients (7.6%) received NAC. The administration increased from 2.5% in 2003 to 13.0% in 2011 (p < 0.001). Use of NAC increased from 0.5% to 2.3% for cT1 tumors, from 2.8% to 27.0% for cT2, from 30.6% to 70.9% for cT3, and from 40.5% to 58.1% for cT4 tumors (p < 0.001). In cN0 patients, use of NAC increased from 1.0% to 4.4% and in clinically node positive patients from 12.0% to 57.5% (p < 0.001). Downsizing of the tumor and BCS are achieved increasingly. In 2011, in three hospitals NAC was administered in <10% of patients, in five hospitals in 10–15% and in two hospitals the proportion of patients receiving NAC was >20% (p < 0.001). Of the 1,402 patients with NAC, 495 patients underwent SNB, 91.5% of whom prior to NAC. In the Netherlands up to one in eight patients receive NAC. The administration of NAC and the percentage of BCS increased over the past decade, especially in cT2 tumors. Considerable hospital variation in the administration of NAC exists.     

Cross‐border Collaboration in the Field of Highly Contagious Livestock Diseases: A General Framework for Policy Support

This paper analyses the potential gains and the main challenges for increased cross‐border collaboration in the control of highly contagious livestock diseases in regions with cross‐border reliance on production and consumption of livestock commodities. The aim of this intensification of cross‐border collaboration is to retain the economic advantages of cross‐border trade in livestock and livestock commodities while maintaining a low risk of highly contagious livestock diseases. From these two foci, possibilities for future policy making with respect to highly contagious livestock diseases are discussed: peacetime cross‐border cooperation to improve the cost‐effectiveness of routine veterinary measures and crisis time cross‐border harmonization of current disease control strategies. A general disease management framework was used to describe the way in which these two fields are related to and affect the epidemiological system and, consequently, how they impact the stakeholders. In addition to this framework, the importance of a good understanding of influencing factors, that is, the production structure of livestock, was stressed because these factors are important determinants of the frequency and magnitude of highly contagious livestock diseases and their economic impact. The use of the suggested integrated approach was illustrated for the extended cross‐border region of the Netherlands and Germany, that is, North Rhine Westphalia and Lower Saxony. For this region, current difficulties in cross‐border trade in livestock and livestock commodities and possibilities for future cross‐border collaboration were examined. The concepts and ideas presented in this paper should foster future development of cross‐border collaboration in animal health control.     

ℋ︁∞ model reduction for uncertain two‐dimensional discrete systems

This paper investigates the problem of ℋ︁_∞ model reduction for two‐dimensional (2‐D) discrete systems with parameter uncertainties residing in a polytope. For a given robustly stable system, our attention is focused on the construction of a reduced‐order model, which also resides in a polytope and approximates the original system well in an ℋ︁_∞ norm sense. Both Fornasini–Marchesini local state‐space (FMLSS) and Roesser models are considered through parameter‐dependent approaches, with sufficient conditions obtained for the existence of admissible reduced‐order solutions. Since these obtained conditions are not expressed as strict linear matrix inequalities (LMIs), the cone complementary linearization method is exploited to cast them into sequential minimization problems subject to LMI constraints, which can be readily solved using standard numerical software. In addition, the development of zeroth order models is also presented. Two numerical examples are provided to show the effectiveness of the proposed theories. Copyright © 2005 John Wiley & Sons, Ltd.