Optimizing Frequency Channels for Adults with Cochlear Implants

Cochlear implants (CIs) are devices used by individuals with hearing loss to improve communication through the use of an electrode array that directly stimulates the auditory nerve. Existing signal processing strategies utilize a logarithmic frequency-to-electrode allocation, mimicking the representation of frequencies along the basilar membrane (high frequencies at the base and low frequencies at the apex). These strategies support some degree of open-set speech recognition for CI users; however, average speech recognition remains well below what normal-hearing adults are capable of. To enhance speech recognition in adult CI users, this study examined one promising alternative to the standard logarithmic frequency-to-electrode allocation maps. The frequency-to-electrode allocation maps were modified to provide more refined representations of the first two (and most important) vowel formant frequencies (energy peaks in vowels that are critical to speech perception). Twelve participants were tested using two different CI maps: one based on existing clinical frequency-to-electrode allocation strategies (Standard) and one designed to improve the resolution of the first two formants, which should especially enhance vowel recognition (Speech). Alternating between these maps, participants listened to and repeated three kinds of stimulus materials: (1) highly meaningful five-word sentences, (2) syntactically correct but not meaningful four-word sentences, and (3) phonetically balanced consonant-vowel-consonant words in isolation. Analyses revealed that some participants benefitted from the Speech strategy. Moreover, an improvement in vowel recognition in words strongly predicted an improvement in recognition of words in sentences. These findings suggest that optimizing the representation of the first two formants enhances speech recognition for CI users. Future efforts should focus on better representing this speech-specific information in modern-day signal processing strategies.No embargoAcademic Major: Speech and Hearing Scienc

Di-μ-oxido-bis-[(1,4,8,11-tetra-aza-cyclo-tetra-decane-κN,N',N'',N''')dimangan-ese(III,IV)] bis-(tetra-phenyl-borate) chloride acetonitrile disolvate.

The title compound, [Mn(2)O(2)(C(10)H(24)N(4))(2)](C(24)H(20)B)(2)Cl·2CH(3)CN, is a mixed-valent Mn(III)/Mn(IV) oxide-bridged mangan-ese dimer with one chloride and two tetra-phenyl-borate counter-anions. There are two non-coordinated mol-ecules of acetonitrile in the formula unit. A center of inversion is present between the two metal atoms, and, consequently, there is no distinction between Mn(III) and Mn(IV) metal centers. In the Mn(2)O(2) core, the Mn-O distances are 1.817 (3) and 1.821 (3) Å. The cyclam ligand is in the cis configuration. The chloride counter-anion resides on a center of symmetry, whereas the tetra-phenyl-borate counter-anion is in a general position. The cyclam ligand is hydrogen bonded to the acetonitrile as well as to the chloride anion. One of the phenyl rings of the anion and the acetonitrile solvent molecule are each disordered over two sets of sites

Direct Potable Reuse of Wastewater

Water is essential to our societies and mankind. Currently, 844 million people across the globe lack access to potable water. By 2025, it is projected that half of the world population will be in a region of water stress. The water crisis is often thought of as a problem limited to places that have always struggled to have clean water, but it is now affecting new areas such as the southwest United States. With increasing population demands and drought, the feasibility of direct potable reuse (DPR) of wastewater is being considered. According to an EPA report in 2017, there are only four operational or planned DPR facilities in the United States. Of these, the El Paso Advanced Water Purification Facility will be the only one to send treated water directly into the distribution system without blending or continuation onto conventional treatment. As demand and water costs increase, we believe that the implementation of our DPR process for wastewater effluent is a viable option for many communities. The primary contaminants in wastewater treatment plant (WWTP) effluent that must be targeted for potable reuse are organics, bacteria, pathogens, viruses, and suspended and dissolved solids. Our process consists of ozone treatment, granular activated carbon (GAC) treatment, a cartridge particulate filter, ultrafiltration, reverse osmosis, and ultraviolet disinfection. Ozone is used to kill microorganisms in the secondary WWTP effluent before it enters the rest of the system to prevent bio-fouling on the equipment. GAC is used to remove the majority of organic contaminants. A cartridge filter is between the GAC and ultrafiltration (UF) to prevent plugging of the UF membrane. Ultrafiltration is used as pretreatment for the reverse osmosis unit. UF was chosen for its ability to remove pathogens and viruses. Reverse osmosis will remove dissolved solids, a necessary step for the contaminated water to become potable. The final step is disinfection by ultraviolet treatment to ensure no live pathogens reach distribution. Experiments were performed to determine if this combination of steps could effectively treat contaminated water. The necessary treatment must be able to reduce the total dissolved solids (TDS) level from 1,200 parts per million to less than 500 parts per million and reduce TOC from 10 parts per million to less than 0.1 parts per million. Fecal bacteria such as coliform must not be present for the water to be considered potable. A full size plant was designed based on the needs of a community of 5,000, using an average water demand of 100 gallons per person per day. The Poo Pig Sooie team has found Silver City, New Mexico (population ≈ 10,000) to be an ideal city for implementation of the DPR process. This plant would be able to supplement 50% of the potable water (equivalent to a city with a population of 5,000) demands of the city for as little as $1.27 per 1,000 gallons

Direct Potable Reuse of Wastewater

Water is essential to our societies and mankind. Currently, 844 million people across the globe lack access to potable water. By 2025, it is projected that half of the world population will be in a region of water stress.5 The water crisis is often thought of as a problem limited to places that have always struggled to have clean water, but it is now affecting new areas such as the southwest United States. With increasing population demands and drought, the feasibility of direct potable reuse (DPR) of wastewater is being considered. According to an EPA report in 2017, there are only four operational or planned DPR facilities in the United States. Of these, the El Paso Advanced Water Purification Facility will be the only one to send treated water directly into the distribution system without blending or continuation onto conventional treatment.1 As demand and water costs increase, we believe that the implementation of our DPR process for wastewater effluent is a viable option for many communities. The primary contaminants in wastewater treatment plant (WWTP) effluent that must be targeted for potable reuse are organics, bacteria, pathogens, viruses, and suspended and dissolved solids. Our process consists of ozone treatment, granular activated carbon (GAC) treatment, a cartridge particulate filter, ultrafiltration, reverse osmosis, and ultraviolet disinfection. Ozone is used to kill microorganisms in the secondary WWTP effluent before it enters the rest of the system to prevent bio-fouling on the equipment. GAC is used to remove the majority of organic contaminants. A cartridge filter is between the GAC and ultrafiltration (UF) to prevent plugging of the UF membrane. Ultrafiltration is used as pretreatment for the reverse osmosis unit. UF was chosen for its ability to remove pathogens and viruses. Reverse osmosis will remove dissolved solids, a necessary step for the contaminated water to become potable. The final step is disinfection by ultraviolet treatment to ensure no live pathogens reach distribution. Experiments were performed to determine if this combination of steps could effectively treat contaminated water. The necessary treatment must be able to reduce the total dissolved solids (TDS) level from 1,200 parts per million to less than 500 parts per million and reduce TOC from 10 parts per million to less than 0.1 parts per million. Fecal bacteria such as coliform must not be present for the water to be considered potable.15 A full size plant was designed based on the needs of a community of 5,000, using an average water demand of 100 gallons per person per day.18 The Poo Pig Sooie team has found Silver City, New Mexico (population ≈ 10,000) to be an ideal city for implementation of the DPR process. This plant would be able to supplement 50% of the potable water (equivalent to a city with a population of 5,000) demands of the city for as little as $1.27 per 1,000 gallons

Di-μ-oxido-bis­[(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4 N,N′,N′′,N′′′)dimangan­ese(III,IV)] bis­(tetra­phenyl­borate) chloride acetonitrile disolvate

The title compound, [Mn2O2(C10H24N4)2](C24H20B)2Cl·2CH3CN, is a mixed-valent MnIII/MnIV oxide-bridged mangan­ese dimer with one chloride and two tetra­phenyl­borate counter-anions. There are two non-coordinated mol­ecules of acetonitrile in the formula unit. A center of inversion is present between the two metal atoms, and, consequently, there is no distinction between MnIII and MnIV metal centers. In the Mn2O2 core, the Mn—O distances are 1.817 (3) and 1.821 (3) Å. The cyclam ligand is in the cis configuration. The chloride counter-anion resides on a center of symmetry, whereas the tetra­phenyl­borate counter-anion is in a general position. The cyclam ligand is hydrogen bonded to the acetonitrile as well as to the chloride anion. One of the phenyl rings of the anion and the acetonitrile solvent molecule are each disordered over two sets of sites

Verbal Learning and Memory After Cochlear Implantation in Postlingually Deaf Adults: Some New Findings with the CVLT-II

OBJECTIVES: Despite the importance of verbal learning and memory in speech and language processing, this domain of cognitive functioning has been virtually ignored in clinical studies of hearing loss and cochlear implants in both adults and children. In this article, we report the results of two studies that used a newly developed visually based version of the California Verbal Learning Test-Second Edition (CVLT-II), a well-known normed neuropsychological measure of verbal learning and memory. DESIGN: The first study established the validity and feasibility of a computer-controlled visual version of the CVLT-II, which eliminates the effects of audibility of spoken stimuli, in groups of young normal-hearing and older normal-hearing (ONH) adults. A second study was then carried out using the visual CVLT-II format with a group of older postlingually deaf experienced cochlear implant (ECI) users (N = 25) and a group of ONH controls (N = 25) who were matched to ECI users for age, socioeconomic status, and nonverbal IQ. In addition to the visual CVLT-II, subjects provided data on demographics, hearing history, nonverbal IQ, reading fluency, vocabulary, and short-term memory span for visually presented digits. ECI participants were also tested for speech recognition in quiet. RESULTS: The ECI and ONH groups did not differ on most measures of verbal learning and memory obtained with the visual CVLT-II, but deficits were identified in ECI participants that were related to recency recall, the buildup of proactive interference, and retrieval-induced forgetting. Within the ECI group, nonverbal fluid IQ, reading fluency, and resistance to the buildup of proactive interference from the CVLT-II consistently predicted better speech recognition outcomes. CONCLUSIONS: Results from this study suggest that several underlying foundational neurocognitive abilities are related to core speech perception outcomes after implantation in older adults. Implications of these findings for explaining individual differences and variability and predicting speech recognition outcomes after implantation are discussed

Service users' perceptions of the effective ingredients in supported employment

Background: The UK government is advocating the use of supported employment to help people on incapacity benefits back to work, with an emphasis on Individual Placement and Support (IPS) models. However there is little UK-based evidence on the key ingredients of effective support. Aim: To ascertain service users' views of what they found helpful about supported employment. Method: Interviews were carried out with 182 people with severe and enduring mental health problems who were actively engaged with one of the six supported employment agencies included in the study. Results: Three themes emerged: emotional support, practical assistance and a client-centred approach. Conclusion: The findings highlight the importance of the quality of support, particularly through interpersonal dynamics, which go beyond the organizational features emphasized in the IPS model