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1.
Environ Sci Technol ; 50(11): 5900-7, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27161852

RESUMO

This research investigated the use of an electrochemical system for regenerating ion-exchange media and for promoting the crystallization of hardness minerals in a fluidized bed crystallization reactor (FBCR). The closed-loop process eliminates the creation of waste brine solutions that are normally produced when regenerating ion-exchange media. A bipolar membrane electrodialysis stack was used to generate acids and bases from 100 mM salt solutions. The acid was used to regenerate weak acid cation (WAC) ion-exchange media used for water softening. The base solutions were used to absorb CO2 gas and to provide a source of alkalinity for removing noncarbonate hardness by WAC media operated in H(+) form. The base solutions were also used to promote the crystallization of CaCO3 and Mg(OH)2 in a FBCR. The overall process removes hardness ions from the water being softened and replaces them with H(+) ions, slightly decreasing the pH value of the softened water. The current utilization efficiency for acid and base production was ∼75% over the operational range of interest, and the energy costs for producing acids and bases were an order of magnitude lower than the costs for purchasing acid and base in bulk quantities. Ion balances indicate that the closed-loop system will accumulate SO4(2-), Cl(-), and alkali metal ions. Acid and base balances indicate that for a typical water, small amounts of base will be accumulated.


Assuntos
Cristalização , Abrandamento da Água , Troca Iônica , Regeneração , Purificação da Água
2.
Behav Res Ther ; 101: 92-107, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29106898

RESUMO

BACKGROUND: While mindfulness-based interventions (MBIs) employ two distinct practices, focused attention (FA) and open monitoring (OM), the integrated delivery of these practices in MBIs precludes understanding of their practice-specific effects or mechanisms of action. The purpose of this study is to isolate hypothesized active ingredients and practice-specific mechanistic target engagement by creating structurally equivalent interventions that differ only by the active ingredient (meditation practice) offered and to test whether the hypothesized components differentially engage the mechanistic targets that they are purported to engage. METHODS: Participants were intended to be representative of American meditators and had mild to severe affective disturbances. Measures of structural equivalence included participant-level (sample characteristics), treatment-level (program structure and duration, program materials, class size, attendance, homework compliance, etc.), and instructor-level variables (training, ratings and adherence/fidelity). Measures of differential validity included analysis of program materials and verification of differential mechanistic target engagement (cognitive and affective skills and beliefs about meditation acquired by participants after the 8-week training). RESULTS: The results indicate successful creation of structurally equivalent FA and OM programs that were matched on participant-level, treatment-level, and instructor-level variables. The interventions also differed as expected with respect to program materials as well as mechanistic targets engaged (skills and beliefs acquired). CONCLUSIONS: These validated 8-week FA and OM training programs can be applied in future research to assess practice-specific effects of meditation.


Assuntos
Sintomas Afetivos/terapia , Controle Comportamental/métodos , Terapia Cognitivo-Comportamental/métodos , Atenção Plena/métodos , Adulto , Feminino , Humanos , Masculino , Resultado do Tratamento , Adulto Jovem
3.
PLoS One ; 10(11): e0140867, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26535904

RESUMO

At a fundamental level, taxonomy of behavior and behavioral tendencies can be described in terms of approach, avoid, or equivocate (i.e., neither approach nor avoid). While there are numerous theories of personality, temperament, and character, few seem to take advantage of parsimonious taxonomy. The present study sought to implement this taxonomy by creating a questionnaire based on a categorization of behavioral temperaments/tendencies first identified in Buddhist accounts over fifteen hundred years ago. Items were developed using historical and contemporary texts of the behavioral temperaments, described as "Greedy/Faithful", "Aversive/Discerning", and "Deluded/Speculative". To both maintain this categorical typology and benefit from the advantageous properties of forced-choice response format (e.g., reduction of response biases), binary pairwise preferences for items were modeled using Latent Class Analysis (LCA). One sample (n1 = 394) was used to estimate the item parameters, and the second sample (n2 = 504) was used to classify the participants using the established parameters and cross-validate the classification against multiple other measures. The cross-validated measure exhibited good nomothetic span (construct-consistent relationships with related measures) that seemed to corroborate the ideas present in the original Buddhist source documents. The final 13-block questionnaire created from the best performing items (the Behavioral Tendencies Questionnaire or BTQ) is a psychometrically valid questionnaire that is historically consistent, based in behavioral tendencies, and promises practical and clinical utility particularly in settings that teach and study meditation practices such as Mindfulness Based Stress Reduction (MBSR).


Assuntos
Psicometria , Adaptação Psicológica , Adulto , Comportamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenvolvimento de Programas , Inquéritos e Questionários , Temperamento
5.
Ann N Y Acad Sci ; 1307: 64-81, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24372471

RESUMO

Buddhist meditation practices have become a topic of widespread interest in both science and medicine. Traditional Buddhist formulations describe meditation as a state of relaxed alertness that must guard against both excessive hyperarousal (restlessness) and excessive hypoarousal (drowsiness, sleep). Modern applications of meditation have emphasized the hypoarousing and relaxing effects without as much emphasis on the arousing or alertness-promoting effects. In an attempt to counterbalance the plethora of data demonstrating the relaxing and hypoarousing effects of Buddhist meditation, this interdisciplinary review aims to provide evidence of meditation's arousing or wake-promoting effects by drawing both from Buddhist textual sources and from scientific studies, including subjective, behavioral, and neuroimaging studies during wakefulness, meditation, and sleep. Factors that may influence whether meditation increases or decreases arousal are discussed, with particular emphasis on dose, expertise, and contemplative trajectory. The course of meditative progress suggests a nonlinear multiphasic trajectory, such that early phases that are more effortful may produce more fatigue and sleep propensity, while later stages produce greater wakefulness as a result of neuroplastic changes and more efficient processing.


Assuntos
Budismo , Meditação/métodos , Sono , Vigília , Nível de Alerta , Mapeamento Encefálico , Eletroencefalografia , Fadiga , Humanos , Plasticidade Neuronal , Fases do Sono
6.
Psychol Addict Behav ; 27(2): 366-79, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22642859

RESUMO

Humans suffer heavily from substance use disorders and other addictions. Despite much effort that has been put into understanding the mechanisms of the addictive process, treatment strategies have remained suboptimal over the past several decades. Mindfulness training, which is based on ancient Buddhist models of human suffering, has recently shown preliminary efficacy in treating addictions. These early models show remarkable similarity to current models of the addictive process, especially in their overlap with operant conditioning (positive and negative reinforcement). Further, they may provide explanatory power for the mechanisms of mindfulness training, including its effects on core addictive elements, such as craving, and the underlying neurobiological processes that may be active therein. In this review, using smoking as an example, we will highlight similarities between ancient and modern views of the addictive process, review studies of mindfulness training for addictions and their effects on craving and other components of this process, and discuss recent neuroimaging findings that may inform our understanding of the neural mechanisms of mindfulness training.


Assuntos
Comportamento Aditivo/psicologia , Budismo/psicologia , Atenção Plena , Modelos Psicológicos , Abandono do Hábito de Fumar/métodos , Fumar/psicologia , Atenção , Comportamento Aditivo/prevenção & controle , Encéfalo/fisiopatologia , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Humanos , Rede Nervosa/fisiologia , Prevenção Secundária , Abandono do Hábito de Fumar/psicologia , Prevenção do Hábito de Fumar
7.
Mindfulness (N Y) ; 4(1)2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24244224

RESUMO

Though relatively new to Western psychological and spiritual cultures, mindfulness training is becoming more widespread in the general public and is beginning to show promise therapeutically for maladies ranging from generalized stress to specific addictions. However, difficulties remain both with individuals being able to learn core concepts and techniques, such as concentration meditation, and more broadly, with treatment interventions not being optimized to helping individuals learn these. In this manuscript, we examine possible contributing factors to these difficulties. We bring together what is known scientifically about basic learning processes such as operant conditioning with some inspirational suggestions drawn from the early Buddhist dialogues collected in the Theravada Buddhist cannon, in particular the description of seven psychological factors known as "the factors of awakening". Bringing together scientific and textual suggestions, we give an overview of how primary operant conditioning processes lead to stress, and importantly, how a minor shift in emphasis in providing mindfulness training may indeed co-opt these very processes for the reduction and cessation of stress and suffering. Finally, we provide suggestions as to how these can be tracked individually and clinically over time.

8.
Front Hum Neurosci ; 7: 440, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23964222

RESUMO

Neurophenomenological studies seek to utilize first-person self-report to elucidate cognitive processes related to physiological data. Grounded theory offers an approach to the qualitative analysis of self-report, whereby theoretical constructs are derived from empirical data. Here we used grounded theory methodology (GTM) to assess how the first-person experience of meditation relates to neural activity in a core region of the default mode network-the posterior cingulate cortex (PCC). We analyzed first-person data consisting of meditators' accounts of their subjective experience during runs of a real time fMRI neurofeedback study of meditation, and third-person data consisting of corresponding feedback graphs of PCC activity during the same runs. We found that for meditators, the subjective experiences of "undistracted awareness" such as "concentration" and "observing sensory experience," and "effortless doing" such as "observing sensory experience," "not efforting," and "contentment," correspond with PCC deactivation. Further, the subjective experiences of "distracted awareness" such as "distraction" and "interpreting," and "controlling" such as "efforting" and "discontentment," correspond with PCC activation. Moreover, we derived several novel hypotheses about how specific qualities of cognitive processes during meditation relate to PCC activity, such as the difference between meditation and "trying to meditate." These findings offer novel insights into the relationship between meditation and mind wandering or self-related thinking and neural activity in the default mode network, driven by first-person reports.

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