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51.
52.
Safren Steven A.; O'Cleirigh Conall; Tan Judy Y.; Raminani Sudha R.; Reilly Laura C.; Otto Michael W.; Mayer Kenneth H. 《Canadian Metallurgical Quarterly》2009,28(1):1
Objective: To evaluate cognitive-behavioral therapy to enhance medication adherence and reduce depression (CBT-AD) in individuals with HIV. Design: A two arm, randomized, controlled, cross-over trial comparing CBT-AD to enhanced treatment as usual only (ETAU). ETAU, which both groups received, included a single-session intervention for adherence and a letter to the patient's provider documenting her or his continued depression. The intervention group also received 10 to 12 sessions of CBT-AD. Main Outcome Measures: Adherence to antiretroviral therapy as assessed by Medication Event Monitoring Systems (MEMs) and depression as assessed by blinded structured evaluation. Results: At the acute outcome assessment (3-months), those who received CBT-AD evidenced significantly greater improvements in medication adherence and depression relative to the comparison group. Those who were originally assigned to the comparison group who chose to cross over to CBT-AD showed similar improvements in both depression and adherence outcomes. Treatment gains for those in the intervention group were generally maintained at 6- and 12-month follow-up assessments. By the end of the follow-up period, those originally assigned CBT-AD demonstrated improvements in plasma HIV RNA concentrations, though these differences did not emerge before the cross-over, and hence there were not between-groups differences. Conclusions: CBT-AD is a potentially efficacious approach for individuals with HIV struggling with depression and adherence. Replication and extension in larger efficacy trials are needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Nuclear magnetic resonance (NMR) spectroscopy has been used effectively in the analysis of elastomeric, soft materials and has been proven to be both sensitive to micro- and macroscopic changes associated with “aging” mechanisms. Traditional analyses, however, rely on empirical formulae containing a large number of (often arbitrary) independent variables. The resulting ambiguity can be circumvented largely by developing models of NMR observables that are based on basic polymer physics. We compare two such models, one previously published and one derived herein, along with two empirical expressions that describe the proton transverse magnetization decay associated with complex polymer networks. One particular extracted parameter, the proton-proton residual dipolar coupling (RDC), can be directly related to network topology, and a comparison of the extracted RDCs reveals high consistency among the models. An expression derived from the properties of a static Gaussian chain can minimize the number of parameters necessarily to describe the solid-like, networked proton population to a single independent parameter, the average RDC, Davg. The distribution of RDCs derived via this methodology is qualitatively similar to those derived from previously published multiple quantum techniques, although quantitative differences between the derived RDCs persist, suggesting that further analysis is necessary. 相似文献
54.
Marion Graf Manuel Thesen Hartmut Krüger Peter Mayer Karlheinz Sünkel 《Inorganic chemistry communications》2009,12(8):701-703
The synthesis of the bis-cyclometalated complex [{Ir(μ-Cl)(ccpz)2}2] (1, cppz = 1-chloro-4-(4-chlorophenyl)-phthalazine) from hydrated iridium(III) chloride and the ligand ccpz in refluxing ethoxyethanol is described. Compound 1 was characterized by spectroscopic means and the crystal structure was determined by X-ray crystallography. The absorption and emission spectra exhibit the new compound as a red-emitting phosphorescent complex. 相似文献
55.
Alex Mayer Enrique R. Vivoni David Kossak Kathleen E. Halvorsen Agustin Robles Morua 《Water Resources Management》2017,31(15):4731-4744
Participatory modeling workshops were held in Sonora, México, with the goal of developing water resources management strategies in a water-stressed basin. A model of the water resources system, consisting of watershed hydrology, water resources infrastructure, and groundwater models, was developed deliberatively in the workshops, along with scenarios of future climate and development. Participants used the final version of the water resources systems model to select management strategies. The performance of the strategies was based on the reliability of meeting current and future demands at a daily time scale over a year’s period. Pre- and post-workshop surveys were developed and administered. The survey questions focused on evaluation of participants’ modeling capacity and the utility and accuracy of the models. The selected water resources strategies and the associated, expected reliability varied widely among participants. Most participants could be clustered into three groups with roughly equal numbers of participants that varied in terms of reliance on expanding infrastructure vs. demand modification; expectations of reliability; and perceptions of social, environmental, and economic impacts. The wide range of strategies chosen and associated reliabilities indicate that there is a substantial degree of uncertainty in how future water resources decisions could be made in the region. The pre- and post-survey results indicate that participants believed their modeling abilities increased and beliefs in the utility of models increased as a result of the workshops. 相似文献
56.
Miljevi? N Boreli-Zdravkovi? D Obradovi? V Golobo?anin D Mayer B 《Water science and technology》2012,66(3):472-478
This paper describes the use of the dual isotope method involving δ(15)N and δ(18)O measurements of dissolved nitrates to assess the origin and fate of groundwater nitrate at the Klju? groundwater source, Serbia. A sampling campaign was conducted in September 2007 during flow conditions obtaining groundwater from observation wells and river water fed by a shallow aquifer hosted in alluvial (sandy-gravel) sediments. Nitrate isotope ratios ranged from +5.3 to +16.9‰ and δ(18)O(NO(3)) values varied from -2.3 to +5.0‰. Two major contamination sources were identified with isotopic compositions characteristic for nitrate derived from nitrification of soil organic nitrogen (+5.3 to +7.8‰ for δ(15)N) resulting in nitrate concentrations of 33.6 and 78.8 mg/L and nitrate derived from animal wastes or human sewage, e.g. via septic systems, yielding δ(15)N values of +9.9 to +11.9‰ and elevated nitrate concentrations of 31.2-245.8 mg/L. The occurrence of nitrification and denitrification was also revealed based on concentration and isotope data for dissolved nitrate. 相似文献
57.
In a series of 3 experiments, 68 undergraduates learned to a criterion of 2 errorless trials to recite the 1st 12 or 18 responses in a pattern based on Base 3. In Exp I, the pattern was presented as letters (w, d, r, dw, dd,?.?.?.) or as numerals (0, 1, 2, 10, 11,?.?.?.). In Exps II and III, the pattern was presented as letters, and Ss were given a letter-to-digit conversion list (w?=?0, d?=?1, r?=?2) either before or after learning. On a posttest, Ss who knew that the pattern related to numerals during learning performed better on transfer tasks such as addition or further counting in Base 3. Results suggest that different rule systems were acquired even though the same levels of performance on the behavioral objective were achieved. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Anja Vogele Maximilian M. Sonner Benjamin Mayer Xueyong Yuan Matthias Weiß Emeline D. S. Nysten Saimon F. Covre da Silva Armando Rastelli Hubert J. Krenner 《Advanced Quantum Technologies》2020,3(2)
The optomechanical coupling of quantum dots and flexural mechanical modes is studied in suspended nanophononic strings. The investigated devices are designed and monolithically fabricated on an (Al)GaAs heterostructure. Radio frequency elastic waves with frequencies ranging between and 400 MHz are generated as Rayleigh surface acoustic waves on the unpatterned substrate and injected as Lamb waves in the nanophononic string. Quantum dots inside the nanophononic string exhibit a 15‐fold enhanced optomechanical modulation compared to those dynamically strained by the Rayleigh surface acoustic wave. Detailed finite element simulations of the phononic mode spectrum of the nanophononic string confirm that the observed modulation arises from valence band deformation potential coupling via shear strain. The corresponding optomechanical coupling parameter is quantified to . This value exceeds that reported for vibrating nanorods by approximately one order of magnitude at 100 times higher frequencies. Using this value, a derived vertical displacement in the range of 10 nm is deduced from the experimentally observed modulation. The results represent an important step toward the creation of large scale optomechanical circuits interfacing single optically active quantum dots with optical and mechanical waves. 相似文献
59.
Jingjie Hu Izzet Altun Zefu Zhang Hassan Albadawi Marcela A. Salomao Joseph L. Mayer L. P. Madhubhani P. Hemachandra Suliman Rehman Rahmi Oklu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(33):2002611
Transcatheter embolization is a minimally invasive procedure that uses embolic agents to intentionally block diseased or injured blood vessels for therapeutic purposes. Embolic agents in clinical practice are limited by recanalization, risk of non-target embolization, failure in coagulopathic patients, high cost, and toxicity. Here, a decellularized cardiac extracellular matrix (ECM)-based nanocomposite hydrogel is developed to provide superior mechanical stability, catheter injectability, retrievability, antibacterial properties, and biological activity to prevent recanalization. The embolic efficacy of the shear-thinning ECM-based hydrogel is shown in a porcine survival model of embolization in the iliac artery and the renal artery. The ECM-based hydrogel promotes arterial vessel wall remodeling and a fibroinflammatory response while undergoing significant biodegradation such that only 25% of the embolic material remains at 14 days. With its unprecedented proregenerative, antibacterial properties coupled with favorable mechanical properties, and its superior performance in anticoagulated blood, the ECM-based hydrogel has the potential to be a next-generation biofunctional embolic agent that can successfully treat a wide range of vascular diseases. 相似文献
60.
Lifeng Huang Naresh Eedugurala Anthony Benasco Song Zhang Kevin S. Mayer Daniel J. Adams Benjamin Fowler Molly M. Lockart Mohammad Saghayezhian Hamas Tahir Eric R. King Sarah Morgan Michael K. Bowman Xiaodan Gu Jason D. Azoulay 《Advanced functional materials》2020,30(24)
Conductive polymers largely derive their electronic functionality from chemical doping, processes by which redox and charge‐transfer reactions form mobile carriers. While decades of research have demonstrated fundamentally new technologies that merge the unique functionality of these materials with the chemical versatility of macromolecules, doping and the resultant material properties are not ideal for many applications. Here, it is demonstrated that open‐shell conjugated polymers comprised of alternating cyclopentadithiophene and thiadiazoloquinoxaline units can achieve high electrical conductivities in their native “undoped” form. Spectroscopic, electrochemical, electron paramagnetic resonance, and magnetic susceptibility measurements demonstrate that this donor–acceptor architecture promotes very narrow bandgaps, strong electronic correlations, high‐spin ground states, and long‐range π‐delocalization. A comparative study of structural variants and processing methodologies demonstrates that the conductivity can be tuned up to 8.18 S cm?1. This exceeds other neutral narrow bandgap conjugated polymers, many doped polymers, radical conductors, and is comparable to commercial grades of poly(styrene‐sulfonate)‐doped poly(3,4‐ethylenedioxythiophene). X‐ray and morphological studies trace the high conductivity to rigid backbone conformations emanating from strong π‐interactions and long‐range ordered structures formed through self‐organization that lead to a network of delocalized open‐shell sites in electronic communication. The results offer a new platform for the transport of charge in molecular systems. 相似文献