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  • Book
    Stanley A. Gelfand, Lauren Calandruccio
    Summary: Introductory audiology is an essential and fundamental aspect of the education of all students who are interested in the two related professions of speech-language pathology and audiology. This book is primarily intended to serve as a comprehensive introductory text for students who are preparing to enter both of these fields. As such, it tries to address the needs of at least two rather different groups of students. Those planning a career in audiology need a broad overview of the field and a firm understanding of its many basic principles so that they have a solid foundation for the future as doctors of audiology in clinical practice.

    Contents:
    Acoustics and Sound Measurement
    Anatomy and Physiology of the Auditory System
    Measurement Principles and the Nature of Hearing
    The Audiometer and Test Environment
    Pure Tone Audiometry
    Auditory System and Related Disorders
    Acoustic Immittance Assessment
    Speech Audiometry
    Clinical Masking
    Behavioral Tests for Audiological Diagnosis
    Physiological Methods in Audiology
    Assessment of Infants and Children
    Audiological Screening
    Nonorganic Hearing Loss
    Audiological Management I
    Audiological Management II
    Effects of Noise and Hearing Conservation.
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  • Article
    Mallick NK, Hassan A, Bhatti RSS, Rafique D, Jaffery AR, Sharif I, Zameer NU, Mustafa H.
    Cureus. 2022 Dec;14(12):e33083.
    Objectives The objective is to assess the overall quality of life (QoL) in patients who had undergone renal transplant within the last three years and correlate this index with various demographic variables such as age, gender, marital status, and education level and to correlate the QoL score calculated vs. the health status perceived by the patients themselves Materials and methods This was an analytical cross-sectional study, carried out over a period of five months. A total of 123 patients were targeted among which data from 79 patients were gathered including all the patients that underwent kidney transplantation in the past three years at a renal transplant center in CMH, Rawalpindi, Pakistan. Non- Probability convenience sampling was used, and data were collected using the WHOQOL-BREF tool that contained 25 questions targeted to four domains (physical, psychological, social, and environmental). The Questionnaire was administered over the phone with proper consent taken beforehand. Data were analyzed using Excel and SPSS version 23. Results A total of 79 patients were administered the questionnaire with the mean age of our study population being 35±11 years out of which 84.5% were male and 15.5% were female. Patients received the kidney from relative donors (98.4%) with the highest percentage being sister donors (30.9%). The majority of patients reported from Punjab (54.4%), with the rest from far-flung rural areas. An estimated 62.5% of the patients presented with other systemic/psychological disorders such as DM+, IHD, HTN, Hepatitis C, depression, etc. The mean global score of these patients was 79.21 which can be broken down into four domains, physical domain 80.40, psychological domain 78.99, social domain 82.70, and environmental domain 74.75. Conclusion In a developing country such as Pakistan, with most of the patients belonging to lower or middle socioeconomic groups, we believe that the patient's own sense of QoL is overshadowed by the mere exuberance of being given a second chance at life which was portrayed by the discrepancies in the perceived vs actual QoL graph. One common recurring theme that was noticed whilst interviewing the patients was that the difficulties they might have faced post-transplant paled in comparison to how grateful they were to live another day. A positive trend was noticed between the time since transplant and the QoL score which could be attributed to various factors such as the use of aggressive immunosuppressants, fear of injury, fear of transplant rejection, etc. in the first-year post-transplant. Demographic variables such as income, age, location, etc. did not affect the scores of these patients on a great scale. The present study aims to guide clinicians in the improvement of long-term outcomes of renal transplantation in Pakistan.
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  • Article
    Bae SH, Shin YJ, Kim HK, Hyon JY, Wee WR, Park SG.
    Sci Rep. 2016 10 04;6:33083.
    This study investigated the effect of vitamin D supplementation in patients with dry eye syndrome (DES) refractory to conventional treatment with vitamin D deficiency. A total of 105 patients with DES refractory to conventional treatment and vitamin D deficiency that was treated with an intramuscular injection of cholecalciferol (200,000 IU). Serum 25-hydroxyvitamin D (25(OH)D) levels were measured. Eye discomfort was assessed using ocular surface disease index (OSDI) and visual analogue pain score (VAS). Tear break-up time (TBUT), fluorescein staining score (FSS), eyelid margin hyperemia, and tear secretion test were measured before treatment, and 2, 6, and 10 weeks after vitamin D supplementation. Mean serum 25(OH)D level was 10.52 ± 4.61 ng/mL. TBUT, and tear secretion test showed an improvement at 2 and 6 weeks after vitamin D supplementation compared to pretreatment values (p < 0.05 for all, paired t-test). Eyelid margin hyperemia and the severity of symptoms showed improvement at 2, 6, and 10 weeks after vitamin D supplementation (p < 0.05 for all). Compared to pre-treatment values, FSS, OSDI and VAS were decreased at 2 weeks (p < 0.05 for all). In conclusion, vitamin D supplementation is effective and useful in the treatment of patients with DES refractory to conventional treatment and with vitamin D deficiency.
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  • Article
    Bijl RC, Cornette JMJ, van den Bosch AE, Duvekot JJ, Molinger J, Willemsen SP, Koning AHJ, Roos-Hesselink JW, Franx A, Steegers-Theunissen RPM, Koster MPH.
    BMJ Open. 2019 11 10;9(11):e033083.
    INTRODUCTION: The importance of cardiovascular health in relation to pregnancy outcome is increasingly acknowledged. Women who develop certain pregnancy complications, in particular preeclampsia, are at higher risk for future cardiovascular disease. Independent of its outcome, pregnancy requires a substantial adaptive response of the maternal cardiovascular system. In the Hemodynamic Adaptation to Pregnancy and Placenta-related Outcome (HAPPO) study, we aim to examine longitudinal maternal haemodynamic adaptation to pregnancy from the preconception period onwards. We hypothesise that women who will develop adverse pregnancy outcomes have impaired cardiovascular health before conception, leading to haemodynamic maladaptation to pregnancy and diminished uteroplacental vascular development.
    METHODS AND ANALYSIS: In this prospective cohort study embedded in the Rotterdam periconception cohort, 200 women with a history of placenta-related pregnancy complications (high-risk group) and 100 women with an uncomplicated obstetric history (low-risk group) will be included. At five moments (preconception, first, second and third trimester and postdelivery), women will undergo an extensive examination of the macrocirculatory and microcirculatory system and uteroplacental vascular development. The main outcome measures are differences in maternal haemodynamic adaptation to pregnancy between women with and without placenta-related pregnancy complications. In a multivariate linear mixed model, the relationship between maternal haemodynamic adaptive parameters, (utero)placental vascularisation indices and clinical outcomes (occurrence of pregnancy complications, embryonic and fetal growth trajectories, miscarriage rate, gestational age at delivery, birth weight) will be studied. Subgroup analysis will be performed to study baseline and trajectory differences between high-risk and low-risk women, independent of subsequent pregnancy outcome.
    ETHICS AND DISSEMINATION: This study protocol was approved by the Medical Ethics Committee of the Erasmus MC, Rotterdam, the Netherlands (MEC 2018-150). Results will be disseminated to the medical community by publications in peer-reviewed journals and presentations at scientific congresses. Also, patient associations will be informed and the public will be informed by dissemination through (social) media.
    TRIAL REGISTRATION NUMBER: NL7394 (www.trialregister.nl).
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  • Article
    Cristian M, Baz RA, Stoica AG, Așchie M, Ghinea MM, Deacu M, Boșoteanu M, Mitroi AF, Dobrin N, Iordache IE, Bălțătescu GI.
    Medicine (Baltimore). 2023 Feb 22;102(8):e33083.
    RATIONALE: In the era of antiretroviral therapy, lymphoma is the primary cause of cancer-related death among human immunodeficiency virus (HIV)-infected people and the most prevalent and aggressive non-Hodgkin lymphoma is diffuse large B cell lymphoma, which usually has an aggressive clinical course. CD5-positive diffuse large B cell lymphoma (DLBCL) is an insufficiently studied, relatively new entity, which accounts for 5% to 10% of the DLBCL population. The current study presents the clinicopathological features, diagnostic approach, and clinical outcomes of this HIV-related lymphoma and highlights the importance of the early diagnosis of CD5-positive DLBCL.
    PATIENT CONCERNS: We present a case of a 30-year-old male patient, with a medical history of HIV-positive serology and antiviral treatment, presenting with diffuse abdominal pain and symptoms related to obstruction or perforation, followed by exploratory laparotomy and surgical resection of the small intestine with other areas of involvement. The surgical specimen was morphologically evaluated and immunohistochemical stained.
    DIAGNOSES AND INTERVENTIONS: Histopathologic examination revealed a diffuse neoplastic proliferation of large B lymphocytes within the small intestine, lacking features of other defined types of large B cell lymphoma. The diagnosis of CD5-positive DLBCL subtype was made after immunostaining with twelve monoclonal antibodies (CD3, CD5, CD10, CD20, CD23, CD30, CD68, Cyclin D1, MUM1, Bcl2, Bcl6, and Ki-67). The expression profile of immunohistochemical markers (CD10, Bcl6, and MUM1) established the cell of origin of this case of DLBCL by using the Hans algorithm.
    LESSONS: The current report highlights the importance of early diagnosis of CD5-positive DLBCL because of its poor prognosis and calls attention to the critical importance to identify immunodeficiencies because doing so affects the types of treatments available. Although cell-of-origin is useful for predicting outcomes, the germinal center B cell like and activated-B cell like subtypes remain heterogeneous, with better, and worse prognostic subsets within each group.
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  • Article
    Goeckeler ZM, Wysolmerski RB.
    J Biol Chem. 2005 Sep 23;280(38):33083-95.
    This study determined the effects of increased intracellular cAMP and cAMP-dependent protein kinase activation on endothelial cell basal and thrombin-induced isometric tension development. Elevation of cAMP and maximal cAMP-dependent protein kinase activation induced by 10 microm forskolin, 40 microm 3-isobutyl-1-methylxanthine caused a 50% reduction in myosin II regulatory light chain (RLC) phosphorylation and a 35% drop in isometric tension, but it did not inhibit thrombin-stimulated increases in RLC phosphorylation and isometric tension. Elevation of cAMP did not alter myosin light chain kinase catalytic activity. However, direct inhibition of myosin light chain kinase with KT5926 resulted in a 90% decrease in RLC phosphorylation and only a minimal decrease in isometric tension, but it prevented thrombin-induced increases in RLC phosphorylation and isometric tension development. We showed that elevated cAMP increases phosphorylation of RhoA 10-fold, and this is accompanied by a 60% decrease in RhoA activity and a 78% increase in RLC phosphatase activity. Evidence is presented that it is this inactivation of RhoA that regulates the decrease in isometric tension through a pathway involving cofilin. Activated cofilin correlates with increased F-actin severing activity in cell extracts from monolayers treated with forskolin/3-isobutyl-1-methylxanthine. Pretreatment of cultures with tautomycin, a protein phosphatase type 1 inhibitor, blocked the effect of cAMP on 1) the dephosphorylation of cofilin, 2) the decrease in RLC phosphorylation, and 3) the decrease in isometric tension. Together, these data provide in vivo evidence that elevated intracellular cAMP regulates endothelial cell isometric tension and RLC phosphorylation through inhibition of RhoA signaling and its downstream pathways that regulate myosin II activity and actin reorganization.
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  • Article
    Skiba MB, Lopez-Pentecost M, Werts SJ, Ingram M, Vogel RM, Enriquez T, Garcia L, Thomson CA.
    JMIR Cancer. 2022 Feb 24;8(1):e33083.
    BACKGROUND: Hispanic survivors of cancer experience increased cancer burden. Lifestyle behaviors, including diet and physical activity, may reduce the cancer burden. There is limited knowledge about the posttreatment lifestyle experiences of Hispanic survivors of cancer living on the United States-Mexico border.
    OBJECTIVE: This study aims to support the development of a stakeholder-informed, culturally relevant, evidence-based lifestyle intervention for Mexican-origin Hispanic survivors of cancer living in a border community to improve their dietary quality and physical activity.
    METHODS: Semistructured interviews with 12 Mexican-origin Hispanic survivors of breast cancer and 7 caregivers were conducted through internet-based teleconferencing. The interviews explored the impact of cancer on lifestyle and treatment-related symptoms, perception of lifestyle as an influence on health after cancer, and intervention content and delivery preferences. Interviews were analyzed using a deductive thematic approach grounded in the Quality of Cancer Survivorship Care Framework.
    RESULTS: Key survivor themes included perception of Mexican diet as unhealthy, need for reliable diet-related information, perceived benefits of physical activity after cancer treatment, family support for healthy lifestyles (physical and emotional), presence of cancer-related symptoms interfering with lifestyle, and financial barriers to living a healthy lifestyle. Among caregivers, key themes included effects of the cancer caregiving experience on caregivers' lifestyle and cancer-preventive behaviors and gratification in providing support to the survivors.
    CONCLUSIONS: The interviews revealed key considerations to the adaptation, development, and implementation of a theory-informed, evidence-based, culturally relevant lifestyle program to support lifestyle behavior change among Mexican-origin Hispanic survivors of cancer living in border communities. Our qualitative findings highlight specific strategies that can be implemented in health promotion programming aimed at encouraging cancer protective behaviors to reduce the burden of cancer and comorbidities in Mexican-origin survivors of cancer living in border communities.
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  • Article
    Ouyang X, Liu B, Xiang X, Zhu Z, Chen L, Song X, Yuan D, Chen C.
    Opt Express. 2020 Oct 26;28(22):33077-33083.
    Photonic crystals coated on the surface of scintillators can be used to improve the light extraction efficiency by partially eliminating the total internal reflection. However, the traditional self-assembly technique is not applicable to the hygroscopic scintillators. In the present investigation, we have proposed an efficient method to prepare the photonic crystals on the surface of CsI(Na) hygroscopic scintillators by a combination of the self-assemble of polystyrene (PS) microspheres and the subsequent dry-transfer procedure. For obtaining optimal parameters of photonic crystals, the light output of the CsI(Na) sample is enhanced by 43.2% compared to the reference sample without photonic crystals under the excitation of alpha particles from 241Am source. The energy resolution is improved from 11.2% to 7.8%. This technique based on the dry-transfer procedure has a promising prospect in the preparation of photonic crystals for hygroscopic scintillators.
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  • Article
    Hornig GJ, Scheuer KG, Dew EB, Zemp R, DeCorby RG.
    Opt Express. 2022 Aug 29;30(18):33083-33096.
    We describe the use of monolithic, buckled-dome cavities as ultrasound sensors. Patterned delamination within a compressively stressed thin film stack produces high-finesse plano-concave optical resonators with sealed and empty cavity regions. The buckled mirror also functions as a flexible membrane, highly responsive to changes in external pressure. Owing to their efficient opto-acousto-mechanical coupling, thermal-displacement-noise limited sensitivity is achieved at low optical interrogation powers and for modest optical (Q ∼ 103) and mechanical (Q ∼ 102) quality factors. We predict and verify broadband (up to ∼ 5 MHz), air-coupled ultrasound detection with noise-equivalent pressure (NEP) as low as ∼ 30-100 µPa/Hz1/2. This corresponds to an ultrasonic force sensitivity ∼ 2 × 10-13 N/Hz1/2 and enables the detection of MHz-range signals propagated over distances as large as ∼ 20 cm in air. In water, thermal-noise-limited sensitivity is demonstrated over a wide frequency range (up to ∼ 30 MHz), with NEP as low as ∼ 100-800 µPa/Hz1/2. These cavities exhibit a nearly omnidirectional response, while being ∼ 3-4 orders of magnitude more sensitive than piezoelectric devices of similar size. Easily realized as large arrays and naturally suited to direct coupling by free-space beams or optical fibers, they offer significant practical advantages over competing optical devices, and thus could be of interest for several emerging applications in medical and industrial ultrasound imaging.
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  • Article
    Szkudlarek HJ, Orlowska P, Lewandowski MH.
    PLoS One. 2012;7(3):e33083.
    BACKGROUND: The olivary pretectal nucleus (OPN) is a small midbrain structure responsible for pupil constriction in response to eye illumination. Previous electrophysiological studies have shown that OPN neurons code light intensity levels and therefore are called luminance detectors. Recently, we described an additional population of OPN neurons, characterized by a slow rhythmic pattern of action potentials in light-on conditions. Rhythmic patterns generated by these cells last for a period of approximately 2 minutes.
    METHODOLOGY: To answer whether oscillatory OPN cells are light responsive and whether oscillatory activity depends on retinal afferents, we performed in vivo electrophysiology experiments on urethane anaesthetized Wistar rats. Extracellular recordings were combined with changes in light conditions (light-dark-light transitions), brief light stimulations of the contralateral eye (diverse illuminances) or intraocular injections of tetrodotoxin (TTX).
    CONCLUSIONS: We found that oscillatory neurons were able to fire rhythmically in darkness and were responsive to eye illumination in a manner resembling that of luminance detectors. Their firing rate increased together with the strength of the light stimulation. In addition, during the train of light pulses, we observed two profiles of responses: oscillation-preserving and oscillation-disrupting, which occurred during low- and high-illuminance stimuli presentation respectively. Moreover, we have shown that contralateral retina inactivation eliminated oscillation and significantly reduced the firing rate of oscillatory cells. These results suggest that contralateral retinal innervation is crucial for the generation of an oscillatory pattern in addition to its role in driving responses to visual stimuli.
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  • Article
    Luo Z, Li J, Zhao L, Zhang N, Chen X, Miao W, Chen W, Liang C.
    RSC Adv. 2021 Oct 04;11(52):33083-33092.
    A self-suspending ultra-low density proppant (UDP) was developed based on the polymerization of the unsaturated carbon double bond. Its performance was characterized by FT-IR and SEM, and the sphericity and roundness, diameter distribution, density, mechanical properties, the conductivity of the propped fracture, and mass loss of different fluids were measured. The test results indicated that the UDP no longer contained the unsaturated carbon double bond and the polymerization took place in the raw material. The fracture surface of UDP is compact and it is not easy to produce debris after compression failure. The sphericity and roundness of UDP were above 0.9, and the high sphericity and roundness provided high conductivity. The stirring speed has a great influence on the diameter of UDP, and the UDP with different sizes could be used to prop the hydraulic fracture to different widths. The average apparent density of UDP is as low as 1.044 g cm-3, and it can be suspended in the fracturing fluid for a long time. The strain in the UDP is higher than that in the ceramsite and quartz sand, but its crushing ratio is far below theirs; therefore, the conductivity of the fracture propped by UDP was higher than that of quartz sand and ceramsite. The solubility of UDP in kerosene, reservoir water, and hydrochloric acid is below 1%, indicating that the UDP is also suitable for acid fracturing with proppant. All the experimental results proved that the self-suspending ultra-low density proppant has great potential use in hydraulic fracturing and acid fracturing.
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  • Article
    Liang C, Liu X, Jiang H, Xu Y, Jia Y.
    ACS Omega. 2023 Sep 12;8(36):33083-33097.
    Asphaltenes are the main substances that stabilize emulsions during the production, processing, and transport of crude oil. The purpose of this research is to investigate the process of asphaltenes forming interfacial films at the oil-water interface by means of dissipative particle dynamics (DPD) and the effect of asphaltenes of different structures on the oil-water interface during the formation of interfacial film. It is demonstrated that the thickness of the interfacial film formed at the oil-water interface gradually increases as the asphaltene concentration rises and the amount of asphaltene adsorbed at the oil-water interface gradually multiplies. Both the number and type of heteroatoms in asphaltenes affect the interfacial behavior of asphaltenes. The interface activity of asphaltenes can be enhanced by increasing the number of heteroatoms in the asphaltene, and the type of heteroatom affects as well the interfacial activity of the asphaltene as it affects the aggregation behavior of the asphaltene in the system. As the number of asphaltene aromatic rings increases, the oil-water interfacial tension (IFT) trends down gradually, while the effect of alkyl side chains on the reduction of IFT of asphaltenes is different, and asphaltenes with medium length alkyl side chains can reduce IFT more efficiently.
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  • Article
    Ren H, Kan Z, Wang Z, Shen M.
    ACS Omega. 2020 Dec 29;5(51):33083-33089.
    Carbon dioxide (CO2) and water (H2O) have been converted into hydrocarbons at temperature ranging from 58 to 242 °C through an artificial photosynthesis reaction catalyzed by nanostructured Co/CoO. The experimental results show that chain hydrocarbons (alkane hydrocarbons) (C n H2n+2, where 3 ≤ n ≤ 16) mainly form at a temperature higher than about 60 °C, the production rate reaches a maximum at 130 °C, and abruptly decreases above 130 °C, and then gradually increases until 220 °C. While the temperature is higher than 220 °C, benzene (C6H6) and its derivatives such as toluene (C7H8), p-xylene (C8H10), and C9H12 form. The modeling of temperature dependence of the reaction rate reveals that the vaporization of the adsorbed water contributes to the sharp peak; the activation energy is estimated as about 1 eV, which is in agreement with the reaction of CO and H2 to synthesize chain hydrocarbons. The experimental results support the mechanism that the chemisorbed CO2 and physisorbed H2O on the CoO surface are disassociated or excited with light, and the disassociated or excited molecules then synthesize hydrocarbons. When most of the water molecules leave from the CoO at temperature higher than 220 °C, the hydrogen source is of very low concentration while the carbon source remain the same because of the chemisorption, and thus benzene and its derivatives with low hydrogen atom number form.
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  • Article
    Ahmed H, Pohl J, Fink NE, Strobel F, Vasta GR.
    J Biol Chem. 1996 Dec 20;271(51):33083-94.
    The detailed characterization of a galectin from the toad (Bufo arenarum Hensel) ovary in its primary structure, carbohydrate specificity, and overall biochemical properties has provided novel information pertaining to structural and evolutionary aspects of the galectin family. The lectin consists of identical single-chain polypeptide subunits composed of 134 amino acids (calculated mass, 14,797 daltons), and its N-terminal residue, alanine, is N-acetylated. When compared to the sequences of known galectins, the B. arenarum galectin exhibited the highest identity (48% for the whole molecule and 77% for the carbohydrate recognition domain (CRD)) with the bovine spleen galectin-1, but surprisingly less identity (38% for the whole molecule and 47% for the CRD) with a galectin from Xenopus laevis skin (Marschal, P., Herrmann, J., Leffler, H., Barondes, S. H., and Cooper, D. N. W. (1992) J. Biol. Chem. 267, 12942-12949). Unlike the X. laevis galectin, the binding activity of the B. arenarum galectin for N-acetyllactosamine, the human blood group A tetrasaccharide and Galbeta1,3GalNAc relative to lactose, was in agreement with that observed for the galectin-1 subgroup and those galectins having "conserved" (type I) CRDs (Ahmed, H., and Vasta, G. R. (1994) Glycobiology 4, 545-549). Moreover, the toad galectin shares three of the six cysteine residues that are conserved in all mammalian galectins-1, but not in the galectins from X. laevis, fish, and invertebrates described so far. Based on the homologies of the B. arenarum galectin with the bovine spleen galectin-1 and X. laevis skin galectin, it should be concluded that within the galectin family the correlation between conservation of primary structure and phylogenetic distances among the source species may not be a direct one as proposed elsewhere (Hirabayashi, J., and Kasai, K. (1993) Glycobiology 3, 297-304). Furthermore, galectins with conserved (type I) CRDs, represented by the B. arenarum ovary galectin, and those with "variable" (type II) CRDs, represented by the X. laevis 16-kDa galectin, clearly constitute distinct subgroups in the extant amphibian taxa and may have diverged early in the evolution of chordate lineages.
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  • Article
    Duan H, Zhao Z, Lu J, Hu W, Zhang Y, Li S, Zhang M, Zhu R, Pang H.
    ACS Appl Mater Interfaces. 2021 Jul 21;13(28):33083-33090.
    Metal organic frameworks (MOFs) have been widely researched and applied in many fields. However, the poor electrical conductivity of many traditional MOFs greatly limits their application in electrochemistry, especially in energy storage. Benefited from the full charge delocalization in the atomical plane, conductive MOFs (c-MOFs) exhibit good electrochemical performance. Besides, unlike graphene, c-MOFs are provided with 1D cylindrical channels, which can facilitate the ion transport and enable high ion conductivity. Transition-metal oxides (TMOs) are promising materials with good electrochemical energy storage performance due to their excellent oxidation-reduction activity. When composited with TMOs, the c-MOFs can significantly improve the capacitance and rate performance. In this work, for the first time, we designed serial MnO2@Ni-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) nanoarrays with different lengths and explored how the lengths influence the electrochemical energy storage performance. By taking advantage of the high redox activity of MnO2 and the excellent electron and ion conductivity in Ni-HHTP, when assembled as the positive electrode material in an aqueous asymmetric supercapacitor, the device displays high energy density, outstanding rate performance, and superior cycle stability. We believe that the results of this work would provide a good prospect for developing other c-MOF composites as a potential class of electrode materials in energy storage and conversion.
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  • Article
    Lu X, Sakai N, Tang D, Li X, Taniguchi T, Ma R, Sasaki T.
    ACS Appl Mater Interfaces. 2020 Jul 22;12(29):33083-33093.
    Efficient electrocatalysts are highly demanded for oxygen evolution reaction (OER) in water splitting and metal-air batteries. Here, superlattice structured materials composed of CoNiFe layered double hydroxide (LDH)/ruthenium oxide nanosheets are synthesized as carbon-free electrocatalysts for OER. The positively charged CoNiFe LDH and negatively charged RuO2.1 are alternately stacked at the molecular level into superlattice-like hybrids by electrostatic interaction upon mixing their dispersions under suitable conditions. Such heterostructured composites are found to act as effective catalysts toward OER of water splitting with a small overpotential of 281 mV and Tafel plot of 48.9 mV/decade. Such composites also serve as efficient carbon-free cathode catalysts for aprotic Li-O2 batteries with remarkable higher specific capacities and lower overvoltages than RuO2 nanoparticles. The superior performance may be attributed to the peculiar superlattice structure, resulting in strong interfacial electronic coupling, better electrical conductivity, and the suppression of side reactions caused by traditional carbon-based materials. Furthermore, potential difference between RuO2.1 and CoNiFe LDH nanosheets is observed directly by scanning Kelvin probe microscopy, indicating that electrostatic fields might be induced in the superlattice structures to benefit the transport of electrons and charged ions as well as the catalytic process.
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  • Article
    Scaparro AM, Miseikis V, Coletti C, Notargiacomo A, Pea M, De Seta M, Di Gaspare L.
    ACS Appl Mater Interfaces. 2016 Dec 07;8(48):33083-33090.
    Germanium is emerging as the substrate of choice for the growth of graphene in CMOS-compatible processes. For future application in next generation devices the accurate control over the properties of high-quality graphene synthesized on Ge surfaces, such as number of layers and domain size, is of paramount importance. Here we investigate the role of the process gas flows on the CVD growth of graphene on Ge(100). The quality and morphology of the deposited material is assessed by using μ-Raman spectroscopy, X-ray photoemission spectroscopy, scanning electron microscopy, and atomic force microscopy. We find that by simply varying the carbon precursor flow different growth regimes yielding to graphene nanoribbons, graphene monolayer, and graphene multilayer are established. We identify the growth conditions yielding to a layer-by-layer growth regime and report on the achievement of homogeneous monolayer graphene with an average intensity ratio of 2D and G bands in the Raman map larger than 3.
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  • Book
    Stanley A. Gelfand.
    Summary: "This textbook attempts to provide a comprehensive overview of audiology at the introductory level; including such topics as acoustics, anatomy and physiology, sound perception, auditory disorders and the nature of hearing impairment, methods of measurement, screening, clinical assessment and clinical management. It is intended to serve as the core text for undergraduate students in speech, language and hearing, and might also serve the needs of beginning-level graduate students who need to learn or review the fundamentals of audiology. It is anticipated that the material will be covered in a one-, two- or three-term undergraduate sequence, depending on the organization of the communication sciences and disorders curriculum at a given college or university"--Provided by publisher

    Contents:
    Acoustics and sound measurement
    Anatomy and physiology of the auditory system
    Measurement principles and the nature of hearing
    The audiometer and test environment
    Pure tone audiometry
    Auditory system and related disorders
    Acoustic immitance assessment
    Speech audiometry
    Clinical masking
    Behavioral tests for audiological diagnosis
    Physiological methods in audiology
    Assessment of infants and children
    Audiological screening
    Nonorganic hearing loss
    Audiological management 1
    Audiological management 2
    Effects of noise and hearing conservation
    Appendix A : Combining OBLs into db SPL and dbA
    Appendix B : Alphabetical listing of spondaic words commonly used in clinical practice
    Appendix C : CID Auditory Test W-22 : word lists 1-4
    Appendix D : Northwestern University Auditory Test No. 6
    Appendix E : Spanish bisyllabic words for speech recognition testing
    Appendix F : Boothroyd isophonemic word lists
    Appendix G : An example of the AzBio sentence lists
    Appendix H : Lists 1 and 2 of the Basic English Lexicon (BEL) sentences
    Appendix I : Lexical Neighborhood Test (LNT)
    Appendix J : Multisyllabic Lexical Neighborhood Test (MLNT)
    Appendix K : PBK-50 (PB Kindergarten) words lists
    Appendix L : Word Intelligibility by Picture (WIPI) Test word lists
    Appendix M : Northwestern University Children's Perception of Speech (NU-CHIPS) Test word lists
    Appendix N : Selected resources for auditory-visual training.
  • Article
    Danielsson J, Kurnik M, Lang L, Oliveberg M.
    J Biol Chem. 2011 Sep 23;286(38):33070-83.
    Demetallation of the homodimeric enzyme Cu/Zn-superoxide dismutase (SOD1) is known to unleash pronounced dynamic motions in the long active-site loops that comprise almost a third of the folded structure. The resulting apo species, which shows increased propensity to aggregate, stands out as the prime disease precursor in amyotrophic lateral sclerosis (ALS). Even so, the detailed structural properties of the apoSOD1 framework have remained elusive and controversial. In this study, we examine the structural interplay between the central apoSOD1 barrel and the active-site loops by simply cutting them off; loops IV and VII were substituted with short Gly-Ala-Gly linkers. The results show that loop removal breaks the dimer interface and leads to soluble, monomeric β-barrels with high structural integrity. NMR-detected nuclear Overhauser effects are found between all of the constituent β-strands, confirming ordered interactions across the whole barrel. Moreover, the breathing motions of the SOD1 barrel are overall insensitive to loop removal and yield hydrogen/deuterium protection factors typical for cooperatively folded proteins (i.e. the active-site loops act as a "bolt-on" domain with little dynamic influence on its structural foundation). The sole exceptions are the relatively low protection factors in β-strand 5 and the turn around Gly-93, a hot spot for ALS-provoking mutations, which decrease even further upon loop removal. Taken together, these data suggest that the cytotoxic function of apoSOD1 does not emerge from its folded ground state but from a high energy intermediate or even from the denatured ensemble.
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  • Article
    Park JK, Keyhani NO, Roseman S.
    J Biol Chem. 2000 Oct 20;275(42):33077-83.
    The major product of bacterial chitinases is N,N'-diacetylchitobiose or (GlcNAc)(2). We have previously demonstrated that (GlcNAc)(2) is taken up unchanged by a specific permease in Vibrio furnissii (unlike Escherichia coli). It is generally held that marine Vibrios further metabolize cytoplasmic (GlcNAc)(2) by hydrolyzing it to two GlcNAcs (i.e. a "chitobiase "). Here we report instead that V. furnissii expresses a novel phosphorylase. The gene, chbP, was cloned into E. coli; the enzyme, ChbP, was purified to apparent homogeneity, and characterized kinetically. The DNA sequence indicates that chbP encodes an 89-kDa protein. The enzymatic reaction was characterized as follows. (GlcNAc)(2)+P(i) GlcNAc-alpha-1-P+GlcNAc K'(cq)=1.0+/-0.2 Reaction 1 The K(m) values for the four substrates were in the range 0.3-1 mm. p-Nitrophenyl-(GlcNAc)(2) was cleaved at 8.5% the rate of (GlcNAc)(2), and p-nitrophenyl (PNP)-GlcNAc was 36% as active as GlcNAc in the reverse direction. All other compounds tested displayed </=1% of the activity of the indicated substrates including: for phosphorolysis, higher chitin oliogsaccharides, (GlcNAc)(n), n = 3-5, cellobiose, PNP-GlcNAc, and PNP-(GlcNAc)(3); for synthesis, (GlcNAc)(n) (n = 2-5), glucose, etc. (GlcNAc)(2) is a major regulator of the chitin catabolic cascade. Conceivably GlcNAc-alpha-1-P plays a similar but different role in regulation.
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