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Biomedical subjects

B T Jones

Publications and source records attributed to B T Jones.

At least 19 recordsLinked to original sources
PubMed2001

An inductively coupled plasma carbon emission detector for aqueous carbohydrate separations by liquid chromatography.

An inductively coupled plasma atomic emission spectrometer is used to detect carbon-containing compounds following separation by high-performance liquid chromatography. A calcium form ligand exchange column with distilled and deionized water as the mobile phase is used to separate carbohydrates. The eluting species are detected by monitoring the carbon atomic emission line at 193.09 nm. The mass detection limits using a photomultiplier tube for sucrose and glucose are 50 ng, while that for fructose is 60 ng. The carbon emission detector should provide the same detection limit for any compound with a similar mass percent of carbon, whether or not the compound exhibits appreciable absorption characteristics. While the carbon emission detector will universally detect any organic compound, it will discriminate against species with high molar absorptivity that may be present at low concentration. Such species may act as interferences in chromatograms generated with conventional UV-visible absorption detectors. To demonstrate the utility of the carbon emission detector, three sugars (glucose, fructose, sucrose) are determined in apple, crangrape, and orange juice.

Carbohydrates↗
PubMed2001

A review of expectancy theory and alcohol consumption.

Research is reviewed on the association between alcohol outcome expectancies and consumption which has led many to argue that manipulating expectancies might be a route to manipulating consumption for problem prevention and treatment. Studies indirectly and directly evaluating this latter position are reviewed. Expectancies predicting treatment outcome: two studies have shown that the more positive expectancies held at treatment, the poorer is treatment outcome, but five other studies have failed to find this. Three related studies have shown that the more negative expectancies held at treatment, the better the treatment outcome. This evaluation provides evidence inconsistent with the main position for positive expectancy and limited support for negative. Expectancy manipulations and ad libitum consumption: three studies in the laboratory have shown that increasing positive expectancies through word priming increases subsequent consumption and two studies have shown that increasing negative expectancies decreases it. A single study in the field showed a similar relationship. This evaluation provides evidence consistent with the main position but is limited by measuring consumption changes over only 1-2 hours. Prevention programmes with expectancy components: seven projects are reviewed in which positive expectancies were targeted, but only two report an expectancy change analysis and in both cases the expectancy change did not relate to subsequent consumption. This evaluation provides evidence inconsistent with the main position. Expectancy challenge: two related studies are reviewed in which positive expectancy challenges reduce subsequent consumption but changes in expectancy were not evaluated as predictors of consumption change. Two studies are reviewed which found a reduction in positive expectancy following expectancy challenge but no reduction in consumption. One study is reviewed in which when negative expectancy was increased in treatment there was a better treatment outcome at 3 months follow-up than when it was not. This evaluation provides evidence inconsistent with the main position for positive expectancy and limited consistent evidence for negative. It is concluded that the research has still to be done that securely links expectancy manipulations with subsequent changes in consumption, and fulfils the early promise from association studies.

Alcohol-Related Disorders↗
PubMed2001

Tungsten coil devices in atomic spectrometry: absorption, fluorescence, and emission.

In this work, tungsten coil (W-Coil) devices are used as atomizers for electrothermal atomization atomic absorption spectrometry (ETAAS), electrothermal atomization laser excited atomic fluorescence spectrometry (ETA-LEAFS), and electrothermal vaporization inductively coupled plasma atomic emission spectrometry (ETV-ICP-AES). For most cases in ETAAS and ETA-LEAFS, limits of detection (LODs) using the W-Coil are within a factor of ten of those observed with commercial graphite furnace systems. LOD for Cd by W-Coil AAS is 10 pg, while LODs for As, Se, Cr, Sb and Pb by W-Coil LEAFS are 950, 320, 1400, 330, and 160 fg, respectively. The compact W-Coil device makes it an ideal atomizer for portable atomic spectrometry instrumentation, especially when coupled with a miniature charge coupled device spectrometer. Alternatively, the atomizer can be used as an inexpensive, modular add-on to an existing commercial ICP-AES system; and the thermal separation of Pb with interference elements Al, Mn, and Fe is demonstrated.

Fluorescence↗
PubMed2000

Desire for alcohol and outcome expectancies as measures of alcohol cue-reactivity in social drinkers.

AIMS: To assess the responsiveness of questionnaire measures of desire to drink and alcohol outcome expectancies. DESIGN: A subjective alcohol cue-reactivity paradigm (alcohol cue: sight, smell, taste) was used with a 2 x 2 between-subject design (n = 88), drink type (soft/alcoholic) and order of assessment (desire-expectancy/expectancy-desire). Covariance analysis controlled for quantity of recent alcohol consumption. SETTING: A quiet alcohol research suite. PARTICIPANTS: Eighty-eight male and female social drinking students, recruited for a 'taste preference' survey. MEASURES: Three composite measures using questionnaire totals and subscales: of desire (DAQ), positive expectancy (AEQ) and negative expectancy (NAEQ). Timeline Follow-back procedure for recent consumption. FINDINGS: Subjective cue-reactivity was found for the DAQ total score and the subscales 'strong intentions and desires' and 'negative reinforcement'. Expectancies did not demonstrate alcohol cue-reactivity. CONCLUSION: The DAQ and subscales are sensitive measures of alcohol cue-reactivity in social drinkers. Potential uses of the subjective cue-reactivity procedure with multi-factorial representations of cue reaction are identified.

Adolescent↗
PubMed1999

The effects of alcohol cues and an alcohol priming dose on a multi-factorial measure of subjective cue reactivity in social drinkers.

RATIONALE: Exploring subjective alcohol cue reactivity in non-clinical samples should assist understanding in clinical samples where additional problems muddy the water. However, exploration is stalled through using insensitive, single-item representations. OBJECTIVE: The effect of alcohol cues and a priming dose of alcohol on a new multi-factorial representation of cue reactivity is sought (DAQ, Desire for Alcohol Questionnaire). METHODS: Prime and Cue exposure are variables in a standard 2x2 between subjects design set within a stooge taste-evaluation experiment. The DAQ was administered after a Prime and Cue exposure phase. RESULTS: Main effects for Cue exposure but not Prime were found for the DAQ total and the subscales Mild desires (positively reinforcing items) and Strong desires/intentions but not Negative reinforcement (negatively reinforcing items) and Controllability; however, there was no interaction. CONCLUSION: The DAQ is a sensitive measure of subjective cue reactivity in social drinkers and its potential in the evaluation of pharmacological interventions is proposed.

Adult↗
PubMed1999

Retained fecalith after laparoscopic appendectomy.

An intraabdominal abscess developed from a retained fecalith following laparoscopic appendectomy. We discuss the prevention and management of retained fecaliths in light of the numerous reports of retained gallstones.

Abdominal Abscess↗
PubMed1996

A comparison of positive and negative alcohol expectancy and value and their multiplicative composite as predictors of post-treatment abstinence survivorship.

Within social learning theory, positive alcohol expectancies represent motivation to drink and negative expectancies, motivation to restrain. It is also recognized that a subjective evaluation of expectancies ought to moderate their impact, although the evidence for this in social drinkers is problematic. This paper addresses the speculation that the moderating effect will be more evident in clinical populations. This study shows that (i) both expectancy and value reliably, independently and equally predict clients' abstinence survivorship following discharge from a treatment programme (and that this is almost entirely confined to the negative rather than positive terms). When (ii) expectancy evaluations are processed against expectancy through multiplicative composites (i.e. expectancy x value), their predictive power is only equivalent to either expectancy or value on its own. However (iii) when the multiplicative composite is assessed following the statistical guidelines advocated by Evans (1991) (i.e. within the same model as its constituents, expectancy and value) the increase in outcome variance explained by its inclusion is negligible and casts doubt upon its use in alcohol research. This does not appear to apply to value, however, and its possible role in treatment is discussed.

Adult↗
PubMed1996

Changes in alcohol expectancies during treatment relate to subsequent abstinence survivorship.

When negative alcohol expectancies are measured appropriately they form at least as secure associations with measures of consumption as has been demonstrated by mainstream expectancy research for positive alcohol expectancies and they can be usefully used to represent a component of motivation to restrain consumption or recover in dependent drinkers. A study is reported in which (i) negative outcome expectancies assessed at admission to treatment reliably predicted number of days to first drink; (ii) the same relationship is discovered for discharge measures (iii) and, although the change is negative expectancies between admission and discharge does not, itself, predict the number of days to first drink, it does when the corresponding admission measure is also taken into account. The same predictive relationships were not found for positive expectancies. Implications for planning treatment are discussed in terms of treatment enhancement rather than treatment matching.

Adult↗
PubMed1995

Blood lead levels in North Carolina painters.

1. Blood lead levels were examined in 127 housepainters in North Carolina between April and September, 1993. Each participant filled out a questionnaire and gave a blood sample. The questionnaire covered the individual's work history, concentrating on paint-removal activities and personal protection, and also covered potential nonoccupational sources of lead exposure. Blood samples were analysed for lead content using atomic absorption spectroscopy. 2. The geometric mean blood lead level was 0.33 mumol L-1 (6.8 micrograms dL-1). No blood lead samples were found to exceed the occupational standard of 1.93 mumol L-1 (40 micrograms dL-1). The three highest samples had levels between 0.97 and 1.45 mumol L-1 (20 and 30 micrograms dL-1); this represented 2.4% of the study sample. 3. No statistical association was found between blood lead levels in these painters and their painting activities, including using dust masks for personal protection. 4. Current painting practices in this group of North Carolina painters do not appear to elevate blood lead levels above the occupational standard.

Adolescent↗
PubMed1994

Negative alcohol expectancy predicts post-treatment abstinence survivorship: the whether, when and why of relapse to a first drink.

Using survival analysis, the association was explored between positive and negative alcohol expectancies measured on admission to a non-residential alcohol dependence treatment unit and post-treatment relapse to a first drink (first slip). A reliable association between negative alcohol expectancy (but not positive) and relapse was found. The active negative alcohol expectancies were distal rather than proximal: proximal expectancies surround consumption ('same day' expectancies) and distal expectancies relate to the 'next-day' following consumption or those longer term expectancies coming from 'continued drinking'. Only the 'next day' component of distal expectancies formed a reliable association with relapse. The use to which negative alcohol expectancy as measured by the Negative Alcohol Expectancy Questionnaire might be put is discussed in terms of (i) a bottom-up representation of motivation for recovery to help treatment match and (ii) a provisor of detailed, client-specific information for structuring motivational interventions.

Adult↗
PubMed1994

Negative and positive alcohol expectancies as predictors of abstinence after discharge from a residential treatment program: a one-month and three-month follow-up study in men.

Male alcohol dependent clients (N = 53), who were given the Alcohol Expectancy Questionnaire and the Negative Alcohol Expectancy Questionnaire upon admission to a residential alcohol treatment program, were successfully followed-up 1 month and 3 months after discharge to assess their compliance with the treatment goal of total abstinence. At 1 month, neither demographic variables nor alcohol expectancies were associated with outcome consumption. At 3 months, however, the demographic variable, age, total negative expectancy (but not total positive) and the two subscales, global positive expectancy and continued-drinking negative expectancy (representing longer term expected negative consequences), were. The potential importance of negative alcohol expectancy in drinking decisions and the limitations of the study were identified.

Adult↗
PubMed1994

A prospective comparison of the status of the deep venous system after treatment with intracaval interruption versus anticoagulation.

The safety and efficacy of caval interruption has been well demonstrated. Likewise, comparisons of caval interruption and anticoagulation have shown similar rates of mean and long term clinical outcome. One concern that continues to be voiced is whether or not anticoagulation enhances venous recovery and function. The present study compares outcome by impedance plethysmography, Duplex scanning and clinical sequelae at six months after the acute illness and treatment with either caval interruption or anticoagulation. The results show no significant differences between the two treatment groups.

Aged↗
PubMed1992

Empirical evidence shows that measuring users' opinions is not a satisfactory way of evaluating computer-assisted learning in nurse education.

Users' opinions have been one of the cornerstones of the evaluation of both CAL, in general, and CAL packages, in particular, in nurse education. This paper reports on two experiments that reliably show student nurses' opinions of their current computer-use are formed more by the change from a previously-used computing facility rather than the actual features that the current one possesses. The use of such opinions as a valid evaluation measure within nursing CAL is, consequently, weakened. The evaluation context in which these experiments are conducted derives from the highly-researched multidisciplinary area of Human-Computer Interaction (HCI), and the experiments are introduced and discussed with respect to the HCI concepts of computer-use and usability which examine the interactions taking place at the human-computer interface. Graphical hypertext and the doctrine of functionality are also introduced and discussed, for these aspects have considerable implications for computer-use and the process of planning and choosing computer-use facilities within nurse education.

Attitude of Health Personnel↗
PubMed1992

Negative and positive expectancies in lone and group problem drinkers.

In this experiment we show that measuring positive expectancy of alcohol use does not discriminate between lone and group problem drinkers whereas measuring negative expectancy does. Reliably, lower measures in group drinkers is consistent with: (i) our view that negative expectancy provides the motivation for problem drinkers to quit and that anything which inhibits the translation of negative experience into negative expectancy will correspondingly inhibit motivation; and with (ii) the observations of others that social (or group) support can, indeed, often inhibit recovery.

Alcohol Drinking↗
PubMed1992

The change process in alcoholics: client motivation and denial in the treatment of alcoholism within the context of contemporary nursing.

Despite being constantly cited as a critical intervening variable in the recovery from alcohol problems, there is a paucity of literature on client motivation. This paper reviews the current literature which impacts on motivation and its importance in treatment and develops in a stepwise manner the revised expectancy/motivation hypothesis, tentatively explaining both motivation and denial as a natural process in behavioural change. Because of the revised expectancy/motivation hypothesis' distinctly defined stages which closely relate to the process of nursing and the qualitative and quantitative measurement it entails which the nursing process demands, it offers a particularly appropriate model for treatment within nurse practice.

Adaptation, Psychological↗
PubMed1991

The Greenfield filter as the primary means of therapy in venous thromboembolic disease.

During a five year period at Akron City Hospital, 165 Greenfield filters were placed in 165 patients. Of this group, 78 patients were available for long term analysis, and of these, 42 did not receive anticoagulation treatment for venous thromboembolic diseases, either acutely or on an outpatient basis. An analysis of the outcome for these 42 patients who had the Greenfield filter only as the primary mode of therapy for the disease included chart review and asking each person a standard set of questions. Leg swelling was the most common complaint, occurring in 33 per cent of patients. Venous stasis ulceration occurred in two patients and recurrent deep venous thrombosis occurred in one patient. When compared with a historical control group with venous thromboembolic disease that was treated with anticoagulation alone, the incidence of these sequelae in Greenfield-treated patients was not significantly different. Finally, in this review, the Greenfield filter is better than 95 per cent effective in the prevention of pulmonary embolism. This is no less effective than anticoagulation alone, the efficacy of which is 95 to 98 per cent. The placement of a Greenfield filter is a safe procedure that can usually be done after a local anesthetic was administered to the patient with a complication rate of less than 10 per cent. Unfortunately, major complications of anticoagulation (usually hemorrhage) are relatively common at a rate of 2 to 15 per cent, and occur more frequently in the older population. It is for reasons of safety of therapy and of an equal or better efficacy that the Greenfield filter is recommended in a broader range of clinical circumstances. In particular, it is concluded that the Greenfield filter should be used as a primary means of therapy in venous thromboembolic disease, particularly in those patients who are more than 65 years of age, when the risks of anticoagulation are most threatening.

Adult↗
PubMed1989

Continuum source atomic absorption spectrometry in a graphite furnace with photodiode array detection.

A graphite furnace continuum source atomic absorption spectrometer using a photodiode array detector is described that provides high-resolution wavelength versus absorbance spectra over a 2.5-nm range for a single atomization step. The multiwavelength detection power allows the simultaneous determination of several elements, reduces problems caused by spectral interferences, and automatically corrects for nonzero background absorbance. Each spectrum is acquired in 0.33 s, and several successive spectra can be obtained during a single run. Three-dimensional wavelength-absorbance-furnace temperature spectra can be obtained by using ramped heating steps to provide a rough separation of elements in a mixture. Limits of detection calculated for 19 elements range from 0.1 pg for magnesium to 700 pg for arsenic. The sampling precision was found to be better than 10% relative standard deviation in all cases, with the precision for a single atomization being greatly increased when multiple absorption lines for a single element are observed in the spectrum. The error found for the measurement of the iron concentration in an NBS standard bronze was 8.5%, with the calculated concentration agreeing with the certified concentration within 95% confidence limits.

Metals↗