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We present a detailed analysis of OH observations from the BEACHON (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen)-ROCS (Rocky Mountain Organic Carbon Study) 2010 field campaign at the Manitou Forest Observatory (MFO), which is a 2-methyl-3-butene-2-ol (MBO) and monoterpene (MT) dominated forest environment. A comprehensive suite of measurements was used to constrain primary production of OH via ozone photolysis, OH recycling from HO2, and OH chemical loss rates, in order to estimate the steady-state concentration of OH. In addition, the University of Washington Chemical Model (UWCM) was used to evaluate the performance of a near-explicit chemical mechanism. The diurnal cycle in OH from the steady-state calculations is in good agreement with measurement. A comparison between the photolytic production rates and the recycling rates from the HO2 + NO reaction shows that recycling rates are ~20 times faster than the photolytic OH production rates from ozone. Thus, we find that direct measurement of the recycling rates and the OH loss rates can provide accurate predictions of OH concentrations. More importantly, we also conclude that a conventional OH recycling pathway (HO2 + NO) can explain the observed OH levels in this non-isoprene environment. This is in contrast to observations in isoprene-dominated regions, where investigators have observed significant underestimation of OH and have speculated that unknown sources of OH are responsible. The highly-constrained UWCM calculation under-predicts observed HO2 by as much as a factor of 8. As HO2 maintains oxidation capacity by recycling to OH, UWCM underestimates observed OH by as much as a factor of 4. When the UWCM calculation is constrained by measured HO2, model calculated OH is in better agreement with the observed OH levels. Conversely, constraining the model to observed OH only slightly reduces the model-measurement HO2 discrepancy, implying unknown HO2 sources. These findings demonstrate the importance of constraining the inputs to, and recycling within, the ROx radical pool (OH + HO2 + RO2).

We present simultaneous fast, in-situ measurements of formaldehyde and glyoxal from two rural campaigns, BEARPEX 2009 and BEACHON-ROCS, both located in Pinus Ponderosa forests with emissions dominated by biogenic volatile organic compounds (VOCs). Despite considerable variability in the formaldehyde and glyoxal concentrations, the ratio of glyoxal to formaldehyde, RGF, displayed a very regular diurnal cycle over nearly 2 weeks of measurements. The only deviations in RGF were toward higher values and were the result of a biomass burning event during BEARPEX 2009 and very fresh anthropogenic influence during BEACHON-ROCS. Other rapid changes in glyoxal and formaldehyde concentrations have hardly any affect on RGF and could reflect transitions between low and high NO regimes. The trend of increased RGF from both anthropogenic reactive VOC mixtures and biomass burning compared to biogenic reactive VOC mixtures is robust due to the short timescales over which the observed changes in RGF occurred. Satellite retrievals, which suggest higher RGF for biogenic areas, are in contrast to our observed trends. It remains important to address this discrepancy, especially in view of the importance of satellite retrievals and in situ measurements for model comparison. In addition, we propose that RGF represents a useful metric for biogenic or anthropogenic reactive VOC mixtures and, in combination with absolute concentrations of glyoxal and formaldehyde, furthermore represents a useful metric for the extent of anthropogenic influence on overall reactive VOC processing via NOx. In particular, RGF yields information about not simply the VOCs dominating reactivity in an airmass, but the VOC processing itself that is directly coupled to ozone and secondary organic aerosol production.

Theα-dicarbonyl compounds glyoxal (CHOCHO) and methyl glyoxal (CH3C(O)CHO) are produced in the atmosphere by the oxidation of hydrocarbons and emitted directly from pyrogenic sources. Measurements of ambient concentrations inform about the rate of hydrocarbon oxidation, oxidative capacity, and secondary organic aerosol (SOA) formation. We present results from a comprehensive instrument comparison effort at two simulation chamber facilities in the US and Europe that included nine instruments, and seven different measurement techniques: broadband cavity enhanced absorption spectroscopy (BBCEAS), cavity-enhanced differential optical absorption spectroscopy (CE-DOAS), white-cell DOAS, Fourier transform infrared spectroscopy (FTIR, two separate instruments), laser-induced phosphorescence (LIP), solid-phase micro extraction (SPME), and proton transfer reaction mass spectrometry (PTR-ToF-MS, two separate instruments; for methyl glyoxal only because no significant response was observed for glyoxal). Experiments at the National Center for Atmospheric Research (NCAR) compare three independent sources of calibration as a function of temperature (293- 330 K). Calibrations from absorption cross-section spectra at UV-visible and IR wavelengths are found to agree within 2% for glyoxal, and 4% for methyl glyoxal at all temperatures; further calibrations based on ion-molecule rate constant calculations agreed within 5% for methyl glyoxal at all temperatures. At the European Photoreactor (EUPHORE) all measurements are calibrated from the same UV-visible spectra (either directly or indirectly), thus minimizing potential systematic bias. We find excellent linearity under idealized conditions (pure glyoxal or methyl glyoxal, R2 > 0:96), and in complex gas mixtures characteristic of dry photochemical smog systems (o-xylene/NOx and isoprene/NOx, R2 > 0:95; R2 ~ 0:65 for offline SPME measurements of methyl glyoxal). The correlations are more variable in humid ambient air mixtures (RH>45 %) for methyl glyoxal (0:58 < R2 < 0:68) than for glyoxal (0:79 < R2 < 0:99). The intercepts of correlations were insignificant for the most part (below the instruments' experimentally determined detection limits); slopes further varied by less than 5% for instruments that could also simultaneously measure NO2. For glyoxal and methyl glyoxal the slopes varied by less than 12 and 17% (both 3-σ) between direct absorption techniques (i.e., calibration from knowledge of the absorption cross section). We find a larger variability among in situ techniques that employ external calibration sources (75-90 %, 3-σ), and/or techniques that employ offline analysis. Our intercomparison reveals existing differences in reports about precision and detection limits in the literature, and enables comparison on a common basis by observing a common air mass. Finally, we evaluate the influence of interfering species (e.g., NO2, O3 and H2O) of relevance in field and laboratory applications. Techniques now exist to conduct fast and accurate measurements of glyoxal at ambient concentrations, and methyl glyoxal under simulated conditions. However, techniques to measure methyl glyoxal at ambient concentrations remain a challenge, and would be desirable. [ABSTRACT FROM AUTHOR]

The San Joaquin Valley (SJV) experiences some of the worst ozone air quality in the US, frequently exceeding the California 8 h standard of 70.4 ppb. To improve our understanding of trends in the number of ozone violations in the SJV, we analyze observed relationships between organic reactivity, nitrogen oxides (NOx), and daily maximum temperature in the southern SJV using measurements made as part of California at the Nexus of Air Quality and Climate Change in 2010 (CalNex-SJV). We find the daytime speciated organic reactivity with respect to OH during CalNex-SJV has a temperature-independent portion with molecules typically associated with motor vehicles being the major component. At high temperatures, characteristic of days with high ozone, the largest portion of the total organic reactivity increases exponentially with temperature and is dominated by small, oxygenated organics and molecules that are unidentified. We use this simple temperature classification to consider changes in organic emissions over the last and next decade. With the CalNex-SJV observations as constraints, we examine the sensitivity of ozone production (P O3) to future NOx and organic reactivity controls. We find that P O3 is NOx-limited at all temperatures on weekends and on weekdays when daily maximum temperatures are greater than 29 °C. As a consequence, NOx reductions are the most effective control option for reducing the frequency of future ozone violations in the southern SJV. [ABSTRACT FROM AUTHOR]

We present a detailed analysis of OH observations from the BEACHON (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen)-ROCS (Rocky Mountain Organic Carbon Study) 2010 field campaign at the Manitou Forest Observatory (MFO), which is a 2-methyl-3-butene-2-ol (MBO) and monoterpene (MT) dominated forest environment. A comprehensive suite of measurements was used to constrain primary production of OH via ozone photolysis, OH recycling from HO2, and OH chemical loss rates, in order to estimate the steady-state concentration of OH. In addition, the University of Washington Chemical Model (UWCM) was used to evaluate the performance of a near-explicit chemical mechanism. The diurnal cycle in OH from the steady-state calculations is in good agreement with measurement. A comparison between the photolytic production rates and the recycling rates from the HO2 +NO reaction shows that recycling rates are ~20 times faster than the photolytic OH production rates from ozone. Thus, we find that direct measurement of the recycling rates and the OH loss rates can provide accurate predictions of OH concentrations. More importantly, we also conclude that a conventional OH recycling pathway (HO2 + NO) can explain the observed OH levels in this non-isoprene environment. This is in contrast to observations in isoprene-dominated regions, where investigators have observed significant underestimation of OH and have speculated that unknown sources of OH are responsible. The highly-constrained UWCM calculation under-predicts observed HO2 by as much as a factor of 8. As HO2 maintains oxidation capacity by recycling to OH, UWCM underestimates observed OH by as much as a factor of 4. When the UWCM calculation is constrained by measured HO2, model calculated OH is in better agreement with the observed OH levels. Conversely, constraining the model to observed OH only slightly reduces the model-measurement HO2 discrepancy, implying unknown HO2 sources. These findings demonstrate the importance of constraining the inputs to, and recycling within, the ROx radical pool (OH +HO2 + RO2). [ABSTRACT FROM AUTHOR]

We present a detailed analysis of OH and HO2 observations from the BEACHON (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen)-ROCS (Rocky Mountain Organic Carbon Study) 2010 field campaign at the Manitou Forest Observatory (MFO), which is a 2-methyl-3-butene-2-ol (MBO) and monoterpene (MT) dominated forest environment. A comprehensive suite of measurements was used to constrain primary production of OH via ozone photolysis, OH recycling from HO2, and OH chemical loss rates, in order to estimate the steady-state concentration of OH. In addition, the University of Washington Chemical Model (UWCM) was used to evaluate the performance of a near-explicit chemical mechanism. The diurnal cycle in OH from the steady-state calculations is in good agreement with measurement. A comparison between the photolytic production rates and the recycling rates from the HO2 +NO reaction shows that recycling rates are ~20 times faster than the photolytic OH production rates from ozone. Thus, we find that direct measurement of the recycling rates and the OH loss rates can provide accurate predictions of OH concentrations. More importantly, we also conclude that a conventional OH recycling pathway (HO2 + NO) can explain the observed OH levels in this non-isoprene environment. This is in contrast to observations in isoprene-dominated regions, where investigators have observed significant underestimation of OH and have speculated that unknown sources of OH are responsible. The highly-constrained UWCM calculation under-predicts observed HO2 by as much as a factor of 8. As HO2 maintains oxidation capacity by recycling to OH, UWCM underestimates observed OH by as much as a factor of 5. When the UWCM calculation is constrained by measured HO2, model calculated OH is in reasonable agreement with the observed OH levels. Conversely, constraining the model to observed OH only slightly reduces the model-measurement HO2 discrepancy, implying unknown HO2 sources. These findings demonstrate the importance of constraining both the inputs to, and recycling within, the ROx radical pool (OH+HO2 +RO2). [ABSTRACT FROM AUTHOR]

The article analyzes the methodology which measures gas-phase glyoxal and methylglyoxal through the laser-induced phosphorescence of glyoxal and methylglyoxal spectrometry (LIPGLOS). It states that the new method can obtain high time resolution, in situ measurements of volatile organic compounds (VOC) via laser-induced phosphorescent decays. It notes that the method allows the simultaneous measurement of both glyoxal and methylglyoxal using a single, nonwavelength- tunable light source.

The development and validation of the HIV-Quality Audit Marker (HIV-QAM), an instrument designed to measure changes in the status of hospitalized AIDS patients due to nursing care, is reported. The HIV-QAM is designed to capture the nurse data-collector's judgment of the status of the patient based upon observations, interviews, record reviews, and listening to inter-shift report. The final version of the 10 item HIV-QAM includes three scales, Self-care (six items; Cronbach's alpha = 0.89), Ambulation (two items, alpha = 0.88), and Psychological Distress (two items, alpha = 0.84). Content validity was supported by selection of items from pre-existing scales, generation of items based on care plans for HIV/AIDS patients, and review and critique of items by a panel of nurse experts. Construct validity was supported by principal components factor analysis and multi-trait scaling analysis. Convergent and divergent concurrent validity with patient symptoms and intensity of nursing care required was demonstrated. The predictive validity of the HIV-QAM for mortality at 3 and 6 months after hospital treatment for Pneumocystis carinii pneumonia was also shown. [ABSTRACT FROM AUTHOR]

The relationships among the biological and physiological indicators of cytopenias in AIDS and measures of quality of life are not well characterized. The purpose of this secondary analysis was to determine the relationships among anemia, neutropenia and thrombocytopenia and characteristics of the individual, physiological markers, symptoms, functional status, general health perceptions, and well-being in people with AIDS. The five dimensions of the Wilson and Cleary model of health-related quality of life provided the conceptual model for this study. In addition to descriptive statistics, logistic regression was used to analyze clusters of variables. The sample of 146 hospitalized patients with AIDS had an 85% prevalence of anemia, a 53% prevalence neutropenia and a 33% prevalence of thrombocytopenia. The mean age was 38 years old, 19% were female, 35% were white, 27% had a history of injection drug use and the mean T-helper cell count was 74 mm3. The five dimensions of the Wilson and Cleary model offered significant predictability for anemia only. Patients with higher symptom scores were more likely to have treatable anemia, defined as a hematocrit of < 30%. Treatable anemia was also associated with lower self-care scores and lower T-helper cells. Fifty-four percent of the cohort were candidates for colony stimulating factors, while only 17% of those eligible received them. These data suggest suboptimal treatment of anemia and neutropenia in this cohort of AIDS patients.

This article describes the Client Adherence Profiling-Intervention Tailoring (CAP-IT) intervention designed to enhance adherence to HIV/AIDS medications and reports the results of a pilot study aimed at assessing the feasibility of CAP-IT. Initially, CAP-IT was designed to be implemented by nurse case managers during regularly scheduled home visits; it is currently under revision for use in an outpatient, ambulatory care setting. CAP-IT is an innovative, structured nursing assessment and care-planning activity that allows a standardized assessment of client needs and tailored highly active antiretroviral therapy adherence intervention strategies. CAP-IT is significantly different from the current standard nursing case management practice. Pilot study results in a sample of 10 home care patients suggests that clients have knowledge and skill deficits related to adherence and in the management of the side effects of medications. In addition, the pilot study supported the acceptability of the protocol to clients and the feasibility of integrating CAP-IT into nurse case manager practice. The pilot study results also provided evidence for the efficacy of CAP-IT. The next steps include testing CAP-IT in a randomized clinical trial to determine its effectiveness.

Symptom management for persons living with HIV disease is recognized as an extremely important component of care management. This article reports the validation of a new sign and symptom assessment tool designed to assess the intensity of HIV-related symptoms using two samples (study 1: n=247; study 2: n=686) of people living with HIV disease. Study 1 data were collected between 1994 and 1996 before the initiation of highly active antiretroviral therapy (HAART). Study 2 data were collected between 1997 and 1998 after the wide adoption of HAART therapy. The initial version of the Sign and Symptom Check-List for Persons with HIV Disease (SSC-HIV) included 41 signs and symptoms. This scale was submitted to a principal components factor analysis with a varimax rotation. The final solution reports six factors explaining 68.9% of the variance. The six symptom clusters (factors), the number of items in the factor, and the Cronbach alpha reliability estimates were: malaise/weakness/fatigue (six items, alpha=0.90); confusion/distress (four items, alpha=0.90); fever/chills (four items, alpha=0.85); gastrointestinal discomfort (four items, alpha=0. 81); shortness of breath (three items, alpha=0.79); and nausea/vomiting (three items, alpha=0.77). These six factors have strong reliability estimates and a stable factor structure that supports the construct validity of the 26-item instrument. Additional evidence supports the concurrent validity of the scale as well as its sensitivity to change over time. The final version of the SSC-HIV is a 26-item scale available for use by clinicians and researchers to measure the patient's self-report of HIV-related signs and symptoms.

The naming of nursing phenomena and representing the phenomena in a standardized manner suitable for encoding in computer-based systems is a challenge for the nursing profession at the national and the international level. Considerable progress has been made in the development of classification systems for nursing practice. The focus of this article is on language systems developed to represent nursing judgements in computer-based systems, in particular the electronic health record. A review of two current systems and their proposed revisions (North American Nursing Diagnosis Association, NANDA, Taxonomies I and II, and the International Classification for Nursing Practice, ICNP, Alpha and Beta versions), according to the features suggested by the Computer-based Patient Record Institute (CPRI) for classification systems appropriate for implementation in computer-based systems, suggests that the evolving versions extend the current versions in terms of sufficient granularity (depth and level of detail) and atomic and compositional character. However, it is not clear from the literature available to date whether the characteristics that are most closely related to definition of a formal terminology (i.e. clear and non-redundant representation of concepts, syntax and grammar for logical constructions of compositional terms, synonyms and language independence) will be part of the evolving vocabularies. Formal terminology models and related tools have the potential to complement, extend, and refine existing nursing classification systems.

A case control design was used to examine quality of life and self-care management strategies in persons living with AIDS (PLWAs) with chronic diarrhea. PLWAs without chronic diarrhea (n = 20) as compared to those with chronic diarrhea (n = 20) reported significantly higher general health perceptions (p = .028). In contrast, comparisons on symptom status scores revealed that PLWAs without chronic diarrhea reported greater fatigue (p = .05), greater psychological distress (p = .005), and greater gastrointestinal discomfort (p = .01). Although the intensity of chronic diarrhea was reported as moderate to severe by 85% of the sample, no single category of self-care management strategies was used by more than 65% of respondents. The number of categories of self-care management activities was significantly correlated with general health perceptions. The study findings support the need to test nursing interventions aimed at improving symptom management in chronic diarrhea and facilitating self-care behaviors including those focused on increasing adherence to prescribed therapeutic regimens.

This study examined the relationships between the five dimensions of the Wilson and Cleary model of health-related quality of life and three self-reported adherence measures in persons living with HIV using a descriptive survey design. Data collection occurred in seven cities across the United States, including university-based AIDS clinics, private practices, public and for-profit hospitals, residential and day-care facilities, community-based organizations, and home care. The three dependent adherence measures studied were "medication nonadherence," "follows provider advice," and "missed appointments." The sample included 420 persons living with HIV disease with a mean age of 39 years of which 20% were women and 51% were white; subjects had a mean CD4 count of 321 mm3. HIV-positive clients with higher symptom scores, particularly depression, were more likely to be nonadherent to medication, not to follow provider advice, and to miss appointments. Participants who reported having a meaningful life, feeling comfortable and well cared for, using their time wisely, and taking time for important things were both more adherent to their medications and more likely to follow provider's advice. No evidence was found demonstrating any relationship between adherence and age, gender, ethnicity, or history of injection drug use. These findings support the need to treat symptoms, particularly depression, and to understand clients' perceptions of their environment as strategies to enhance adherence. A limitation of this study was that adherence was measured only by self-report; however, the study did expand the concept of adherence in HIV care beyond medication adherence to include following instructions and keeping appointments.

The purpose of this secondary analysis was to test empirically the influence of biological and physiological variables, symptom status, functional status, general health perceptions, characteristics of the individual and characteristics of the environment on overall quality of life in persons living with HIV disease. Path analysis, using multiple linear regression, was used to examine the fit between a health-related quality of life (HRQOL) theoretical model and data from a sample of 142 persons with an AIDS diagnosis. Thirty-two per cent of the variance in overall quality of life was explained by the HRQOL model with symptom status having the greatest influence (beta = -0.237, R2(Y x 2) = 5%). This analysis suggests that symptom status, functional status and general health perceptions are key dimensions of HRQOL. With a focus on prevention, health promotion, symptom management, and the alleviation of acute and chronic illness effects, HRQOL may be appropriate for capturing the outcomes of nursing interventions.

Efforts to develop an International Classification for Nursing Practice (ICNP) were initiated nearly a decade ago. To update nurses on progress, below is a critical review of the ICNP using the Computer-based Patient Record Institute (CPRI) Features Framework and a discussion of its relevance to current US efforts: 1) the activities of the American Nurses' Association (ANA) Steering Committee on Databases To Support Clinical Nursing Practice; 2) implementation of formal approaches for representing nursing concepts and 3) Health Level 7 standards.