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Women with Alcohol use disorder (AUD) are more likely than men to have co-occurring depression, drink to cope with negative affect (NA), and cite negative affect as a contributor to relapse. Among AUD treatment seekers, low behavioral activation, NA, and reduced self-efficacy in abstaining from alcohol (e.g., in tempting situations) are relapse risk factors. This study investigated the association between behavioral activation, affective states, and self-efficacy among treatment-seeking women. Participants were 70 women (M = 40.50, SD = 11.59 years of age) with elevated depressive symptoms seeking AUD treatment. The Behavioral Activation for Depression Scale (BADS) was used to assess environmental engagement. The Alcohol Abstinence Self-Efficacy (AASE) scale was used to assess temptation to drink in contexts of positive and negative affect, and general positive and negative affect were assessed with the Positive and Negative Affect Schedule. Results indicated that behavioral activation was directly correlated with positive affect (PA; r = .62, p < .001) and inversely correlated with depression (r = -.35, p = .004), negative affect (r = -.39, p = .001), and temptation to drink in the context of negative affect (r = -.33, p = .006). After controlling for depressive symptoms, behavioral activation continued to be associated with greater general positive affect (β = .595, p < .001) and lower temptation to drink in the context of negative affect (β = -.348 p = .008). Our results suggest a nuanced association between behavioral activation, negative affect, and temptations to drink that is not accounted by depressive symptoms. Self-efficacy to abstain from drinking in a negative affect context should be considered when designing AUD interventions for women. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Early recovery from alcohol use disorder (AUD) is commonly associated with high levels of negative affect, stress, and emotional vulnerability, which confer significant relapse risk. Emotion differentiation-the ability to distinguish between discrete emotions-has been shown to predict relapse after treatment for a drug use disorder, but this relationship has not been explored in individuals recovering from AUD.The current study used thrice daily random and up to thrice daily self-initiated ecological momentary assessment surveys (N = 42, observations = 915) to examine whether 1) moments of high affective arousal are characterized by momentary differences in emotion differentiation among individuals in the first year of a current AUD recovery attempt, and 2) individuals' average emotion differentiation would predict subsequent alcohol use measured by the timeline follow-back over a 3-month follow-up period.Multilevel models showed that moments (Level 1) of higher-than-average negative affect (p 0.001) and/or stress (p = 0.033) were characterized by less negative emotion differentiation, while moments of higher-than-average positive affect were characterized by greater positive emotion differentiation (p 0.001). At the between-person level (Level 2), participants with higher stress overall had lower negative emotion differentiation (p = 0.009). Linear regression showed that average negative, but not positive, emotion differentiation was inversely associated with percent drinking days over the subsequent 3-month follow-up period (p = 0.042). Neither form of average emotion differentiation was associated with drinking quantity.We found that for individuals in early AUD recovery, affective states are associated with acute shifts in the capacity for emotion differentiation. Further, we found that average negative emotion differentiation prospectively predicts subsequent alcohol use.

OBJECTIVE: Although stress is a well-known predictor of alcohol use lapses among individuals seeking recovery from alcohol use disorder (AUD), most research has relied on retrospective self-report using conventional questionnaires that explore stress effects at the level of the mean. Ecological momentary assessment (EMA) overcomes many of the shortcomings of questionnaire-based, retrospective self-report by using real-time, in-the-environment evaluations for the acquisition of ecologically valid data that can also capture stress variability. The present investigation used EMA to disentangle stress effects on alcohol lapses among individuals in the first year of an AUD recovery attempt by exploring associations between mean-level stress, stress variability, and subsequent alcohol use. METHOD: Participants (N = 42) completed 6 days of EMA monitoring and were then followed up 90 days later to assess alcohol use. Putative associations were explored using hierarchical regression controlling for demographic factors and pre-baseline alcohol use, with percentage days abstinent from alcohol at follow-up as the outcome variable. RESULTS: An interaction effect was observed such that the combination of high mean stress level and high stress variability was associated with the lowest percentage of days abstinent. For those with high mean stress levels, this relationship was attenuated as stress variability decreased. CONCLUSIONS: The findings support previous research linking stress to alcohol use lapses; however, these results indicate that the stress/alcohol use relationship is more nuanced than previously described. Our findings suggest that stress variability should also be considered in clinical contexts when assessing risk conferred by mean-level stress.

Difficulty regulating substance use is a core feature of addiction that can manifest as unplanned use. This study sought to identify internal and situational influences on unplanned marijuana use among youth ages 15 to 24 years (N = 85; 48% female; 27% age

International audience; The kinetics of the electrochemical lithium intercalation in the nitridonickelate Li x Ni 0.67 N (1.67 ≤ x ≤ 2.17) is investigated by electrochemical impedance spectroscopy during a full reduction-oxidation cycle in a two-electrode cell. The layered structure of this anode material delivers a reversible and stable specific capacity of 200 mAh g-1 over 100 cycles at C/10 near 0.5 V vs Li + /Li. The equivalent electric circuit simulation allows a full assignment of the impedance spectra, with different contributions including the SEI layers on each electrode, charge transfer and Li diffusion. The calculated lithium diffusion coefficient value of approximately 5×10 −9 cm 2 s −1 almost does not vary with the lithium content in Li x Ni 0.67 N (1.67 ≤ x ≤ 2.17). Conversely, the charge transfer resistance (R ct) is found to strongly depend on the depth of reduction to be maximum for the fully reduced electrode, with a totally reversible behavior during oxidation. The overall impedance of the cell remains stable upon long cycling, which indicates a good chemical stability of the SEI on Li x Ni 0.67 N as well as 2 remarkable structural and chemical stability of the nitridonickelate upon cycles. The present kinetic findings shed light on the remarkable "zero-strain" behavior of this negative electrode material presenting numerous Li vacancies.

Highlights • More than 80% of patients with facioscapulohumeral muscular dystrophy (FSHD) report shoulder instability that affects daily life. • Despite this, only 44.4% engaged with exercises that target the upper body. • There is a lack of evidence to inform upper limb FSHD rehabilitation exercises. • Patients with FSHD support the need for further research in upper limb exercises., Objective To identify (1) what exercise modalities people living with facioscapulohumeral muscular dystrophy (FSHD) are undertaking in the community as a part of their ongoing rehabilitation and (2) what future research projects would gain the support of people with FSHD. Design An online questionnaire composed of open and closed questions. Conventional content analysis was used for open questions, and quantitative analysis was used for closed questions. Setting Online questionnaire distributed to a United Kingdom FSHD registry. Participants A total of 232 patients on the United Kingdom FSHD registry (N=232). Interventions None. Main Outcome Measures None. Results A response rate of 43.6% was achieved with 232 of 532 patients completing the survey. Despite 85.8% (n=199) of patients experiencing shoulder instability that affects daily living, only 44.4% (n=103) engaged with exercises targeting the upper body. The themes from the data were understanding of disease mechanism shaping exercise choice, lack of understanding about the condition and the benefit of exercise, support from professionals, barriers to exercise, and thoughts about future research. Participants (92.2%, n=214) agreed additional research into upper limb exercises is needed and felt a 3-month arm cycling intervention with monthly clinical visits and magnetic resonance imaging would be appropriate. Conclusions Exercise selection was variable among patients with FSHD, and lack of information, pain, fatigue, availability and access to facilities, cost, and time were identified as barriers to exercise. This may account for the limited engagement with upper limb rehabilitation despite the high percentage of shoulder instability in patients with FSHD. Further research is needed to develop evidence-based exercise interventions, and guidance for upper limb exercise prescription in FSHD, and patients are supportive of this.

BACKGROUND: Alcohol craving is common among adolescents, stronger among those with more alcohol-related problems, and predicts drinking levels in their daily lives. Yet, the conditions that predict momentary changes in craving in real time among adolescents remain unclear. OBJECTIVES: This study examined interactive effects of momentary risk-taking propensity and affect on adolescents’ alcohol craving by leveraging ecological momentary assessment (EMA) methods. METHODS: Participants were 29 adolescents ages 15-19 years (55% female; 69% White; 10% Black; 17% Hispanic); 45% met criteria for alcohol dependence. Following a laboratory session that captured self-report and behavioral assessments, including the well-established Balloon Analogue Risk Task (BART: Lejuez et al., 2002), participants completed multiple daily assessments of alcohol craving, positive and negative affect, and risk propensity for approximately one week. Momentary risk propensity was captured in real-world settings via an EMA behavioral task (“Balloon Game”). RESULTS: Mixed-effects models with EMA reports (Level 1) nested within participants (Level 2) revealed the majority (74%) of variability in “Balloon Game” performance was due to within-person, momentary, fluctuations. Greater momentary positive affect predicted increased alcohol craving, but only when participants exhibited heightened risk-taking propensity. Negative affect did not influence the relation between momentary risk-taking and craving. CONCLUSIONS/IMPORTANCE: Momentary fluctuations in positive affect predicted acute increases in craving but only in moments when adolescents demonstrated higher levels of risk-taking propensity, as captured with an EMA-delivered behavioral task. Momentary risk-taking assessments offer new avenues to substantiate dominant theories on the driving mechanisms of craving and alcohol use among adolescents.

Theories of addiction posit that stimuli associated with drug use, including both exteroceptive (e.g., paraphernalia) and interoceptive (e.g., feeling tense or stressed), evoke craving and contribute to the pathogenesis of substance misuse. Control over drug cue response and stress is essential for moderating use. Building from laboratory data supporting associations between cue exposure, stress, and craving, this study tested whether these associations generalize to real-world settings and examined whether a well-vetted neurocognitive control capacity (i.e., working memory, or WM) moderated associations. Youths ( N = 85; 15–24 years old) completed baseline and ecological momentary assessments. Cue exposure and participants’ average stress predicted higher craving. Youths with weaker WM experienced stronger craving at higher-stress moments but not when faced with cues. Interactions were present for both previous-moment and same-moment stress. Craving among adolescents with stronger WM was not swayed by momentary stress. Findings suggest that stronger WM protects against craving at more stressful moments.

This study builds upon research indicating that focusing narrowly on model fit when evaluating factor analytic models can lead to problematic inferences regarding the nature of item sets, as well as how models should be applied to inform measure development and validation. To advance research in this area, we present concrete examples relevant to researchers in clinical, personality, and related subfields highlighting two specific scenarios when an overreliance on model fit may be problematic. Specifically, we present data analytic examples showing that focusing narrowly on model fit may lead to (a) incorrect conclusions that heterogeneous item sets reflect narrower homogeneous constructs and (b) the retention of potentially problematic items when developing assessment measures. We use both interview data from adult outpatients (N = 2,149) and self-report data from adults recruited online (N = 547) to demonstrate the importance of these issues across sample types and assessment methods. Following demonstrations with these data, we make recommendations focusing on how other model characteristics (e.g., factor loading patterns; carefully considering the content and nature of factor indicators) should be considered in addition to information provided by model fit indices when evaluating factor analytic models.

Despite being multifaceted in nature, positive emotional (PE) experiences often are studied using only global PE ratings, and measures assessing more specific PE facets do not converge in their assessment approaches. To address these issues, we examined hierarchical factor structures of ratings of positive emotionality, which reflect propensities toward experiencing PE, in both online community adult (N = 375) and undergraduate (N = 447) samples. Preregistered analyses indicated (a) a broad distinction between tendencies to experience social affection and other PE types, and that (b) PE ratings can be differentiated by as many as four replicable factors of Joviality, Social Affection, Serenity, and Attentiveness. These PE dimensions were associated with distinct personality and psychopathology profiles. Examples of these distinctive associations included Joviality displaying robust positive associations with grandiosity and exhibitionism; conversely, although Social Affection and Joviality were strongly correlated, Social Affection showed associations in the opposite direction with grandiosity and exhibitionism. Other notable results include Serenity (e.g., feeling relaxed) showing negative associations with negative emotionality at a magnitude indicating that Serenity may reflect low levels of negative emotionality to a considerable degree. Collectively, these results highlight the need to consider distinct PE facets in addition to global PE ratings when assessing PE, as important nuance may be lost otherwise. Furthermore, our results indicate the need for additional research clarifying PE structure at different levels of abstraction to inform future measure development efforts and assessment approaches.

Purpose: The study aims to identify exercise programmes used by Facioscapulohumeral dystrophy (FSHD) patients in the community, along with barriers and perceptions. Methods: A web based survey, distributed to patients on the UK FSHD registry, and focus groups were conducted. Thematic analysis was conducted on answers to survey questions supported by focus group notes, from seven FSHD patients. Results: A response rate of 43.6% was achieved with 232 out of 532 patients completing the survey. Only 44.4% engaged with exercises targeting the upper body. The themes from the data were: 1) Understanding of disease mechanism shaping exercise choice 2) Lack of understanding about the condition and how exercise interacts with it 3) Support from professionals 4) Barriers to exercise and 5) Thoughts about future research. Conclusion: Exercise selection was variable amongst FSHD patients. Lack of information, pain, fatigue, availability and access to facilities, cost and time were identified as barriers to exercise. Participants (92.2%) agreed additional research into upper limb exercises is needed and felt a 3-month arm cycling intervention with monthly clinical visits and MRI imaging would be appropriate. Further research is needed to develop evidence based exercise interventions and guidance for upper limb exercise prescription in FSHD.

RATIONALE: Coping with negative affect is central to several prominent etiological models of alcohol use. These models posit that alcohol use becomes negatively reinforced due to its ability to alleviate negative affect. However, there have been mixed findings when testing this association at the event-level. OBJECTIVES: The current experience sampling study sought to clarify this by testing if 1) within-person changes in the perceived difficulty of managing emotional distress is a significant predictor of alcohol consumption, over and above levels negative and positive affect and 2) whether acute changes in affective experiences give rise to increased attentional bias toward alcohol-related cues in the environment and if attentional bias mediates the association between difficulty managing emotions and alcohol consumption. Participants were 92 college students aged 18–25, who drink alcohol at least moderately. METHODS: Participants completed 28-days of experiencing sampling measures on their mood, difficulty managing emotions, alcohol-related attentional biases, and drinking. RESULTS: Findings showed that neither negative affect nor difficult managing emotions had significant effects on alcohol use. However, positive affect exhibited the expected associations with both attentional biases and drinking. State positive affect predicted acute increases in attentional biases and drinking, whereas trait positive affect was inversely associated with trait attentional biases and alcohol use. Alcohol-related attentional biases exhibited significant within-person variance; however, its relationship with drinking was only significant when the constructs were assessed concurrently at night and did not mediate the relationship between affect and alcohol use. CONCLUSIONS: Results highlight the importance of positive affect in this population.

The Mood Disorder Questionnaire is a screening measure for bipolar disorder, previously found to comprise separate Positive and Negative Activation subscales. We sought to replicate these factors and examine their associations with a range of psychopathology. To further explicate the nature of Negative Activation, we examined associations with the Difficulties in Emotion Regulation Scale, a measure of emotion dysregulation. The sample consisted of 1,787 participants from an outpatient treatment facility. Confirmatory factor analysis replicated the existence of Positive and Negative Activation subscales. Logistic regressions, as hypothesized, found that Positive Activation was positively associated only with bipolar disorder, while Negative Activation was associated with almost all disorders. The Impulse and Goals subscales of the Difficulties in Emotion Regulation Scale were uniquely associated with Negative Activation, suggesting it may specifically assess impulsive behavior in emotional situations. The findings suggest that it may be important to attend to both Mood Disorder Questionnaire subscales.

Fungal derived phytohormones play a key role in regulating plant-pathogen interactions however deciphering the separate contribution of the pathogen from the plant during infection has been difficult. Here the Ustilago maydis-Zea mays pathosystem was used to investigate this chemical exchange. U. maydis, the causative agent of corn smut, produces cytokinins (CK) which are a group of phytohormones responsible for directing plant development. The characteristic symptom of smut disease is the formation of tumours composed of plant and fungal tissue. Isopentenyltransferase (IPT) catalyzes the rate limiting step in CK biosynthesis and U. maydis strains in which the sole tRNA-ipt gene was deleted no longer produced CKs. These deletion strains elicit fewer, smaller tumours than SG200. High performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI MS/MS) was used to detect and quantify phytohormone levels in infected tissue. This revealed that key hormone changes in SG200 infections were not present in deletion strains; suggesting that CK production by U. maydis is required for the altered phytohormone profile in infected tissue relative to uninfected tissue. Separate analyses indicated that U. maydis tRNA-ipt mutants may be altered in their ability to metabolize CKs taken up from the environment. Mining the U. maydis genome identified genes coding putative CK signaling and biosynthesis proteins. This article is protected by copyright. All rights reserved.

This study modelled associations between gender, ruminative cognitive style, alcohol use, and the time course of negative affect over the course of 43,111 random assessments in the natural environment. Participants (N = 263) completed 49 days of experience sampling over 1.3 years. The data indicated that rumination at baseline was positively associated with alcohol dependence symptoms at baseline as well as higher negative affect over the course of the study. Consistent with negative reinforcement models, drinking served to decrease the persistence of negative affect from moment to moment. However, this ameliorative effect of drinking was evident only among women, suggesting an increased risk for negative reinforcement driven drinking behaviour. In addition, rumination appeared to counteract the desired effects of alcohol on mood among women. This suggests that women who ruminate more may be motivated to consume larger amounts of alcohol to achieve the desired effects. Overall, the results indicate that ruminative cognitive style and the persistence of negative affect from moment to moment may reflect an individual vulnerability for the development of alcohol use disorder especially among women.

Fabrum Solutions and Callaghan Innovation have been developing large pulse tube cryocoolers based on Callaghan Innovation's diaphragm pressure wave generators (DPWGs). The pulse tube's lack of moving parts in combination with the DPWG's metal diaphragms produces a cost-effective, long-life, and robust cryocooler. The DPWG has had ten years of development, resulting in a series of DPWGs ranging in input powers from 0.5 to 30 kW that have been coupled to a variety of inline and coaxial pulse tubes. Two DPWGs have each had in excess of 7000 h running to date. A 330-cc DPWG was designed and manufactured to run with an inline pulse tube with a target refrigeration power of 330 W at 77 K. Absolut System carried out the pulse tube design, and manufacture was done by Fabrum Solutions, with integration and testing by Callaghan Innovation. Over 450 W of cooling power at 77 K was achieved from the cryocooler. A sealed condensation chamber was added to the cold head and connected to a Dewar via vacuum insulated lines for nitrogen liquefaction. Three such pulse tubes were combined on a single 1000-cc DPWG to produce over 1000 W at 77 K. This paper details the development of the PTC330 and PTC1000 cryocoolers from initial laboratory prototypes to commercial products, integrated into liquefiers and ready for use in applications such as liquid nitrogen production, reliquefaction of storage tank boiloff, or cooling of high-temperature superconductor applications.

RATIONALE: Alcohol consumption in adolescents and emerging adults is a significant issue. However, our understanding of the topography of alcohol use within drinking episodes in this population is at a nascent stage. OBJECTIVES: This study characterized rate of alcohol consumption in the daily lives of problem drinkers ages 16–24 years (N = 75). We examined whether AUD symptoms and the presence of peers, factors relevant to alcohol consumption in youth, were associated with rate of consumption. METHODS: Ecological momentary assessment (EMA) was used (N(observations) = 799). Rate of consumption was defined as change in estimated blood alcohol concentration (eBAC) relative to the start of the drinking episode. Piecewise multi-level modeling was used to test hypotheses. As a comparison, we examined whether indicators of quantity and frequency (Q-F) were associated with AUD symptoms and presence of peers. RESULTS: For all participants, eBAC increased sharply early in the episode, then plateaued. Participants with more AUD symptoms or who were in the presence of peers had significantly steeper increases in eBAC over the early part of the episode. Participants with more AUD symptoms were also more likely to engage in binge-like behavior. For Q-F, only peak eBAC and peak number of standard drinks were associated with AUD symptoms, and not presence of peers. CONCLUSIONS: Findings highlight the value of rate of consumption as an indicator of use in youth, one sensitive to the influence of relevant person-level and situational factors. Intervention efforts may benefit from targeting the speed at which youth drink.

Research on alcohol use depends heavily on the validity of self-reported drinking. The present paper presents data from 647 days of self-monitoring with a transdermal alcohol sensor by 60 young adults. We utilized a biochemical measure, transdermal alcohol assessment with the WrisTAS, to examine the convergent validity of three approaches to collecting daily self-report drinking data: experience sampling, daily morning reports of the previous night, and 1-week timeline follow-back (TLFB) assessments. We tested associations between three pharmacokinetic indices (peak concentration, area under the curve (AUC), and time to reach peak concentration) derived from the transdermal alcohol signal and within- and between- person variation in alcohol dependence symptoms. The WrisTAS data corroborated 85.74% of self-reported drinking days based on the experience sampling data. The TLFB assessment and combined experience sampling and morning reports agreed on 87.27% of drinking days. Drinks per drinking day did not vary as a function of wearing or not wearing the sensor; this indicates that participants provided consistent reports of their drinking regardless of biochemical verification. In respect to self-reported alcohol dependence symptoms, the AUC of the WrisTAS alcohol signal was associated with dependence symptoms at both the within- and between- person level. Furthermore, alcohol dependence symptoms at baseline predicted drinking episodes characterized in biochemical data by both higher peak alcohol concentration and faster time to reach peak concentration. The results support the validity of self-report alcohol data, provide empirical data useful for optimal design of daily process sampling, and provide an initial demonstration of the use of transdermal alcohol assessment to characterize drinking dynamics associated with risk for alcohol dependence.

This study tested a model linking sensitivity to punishment (SP) and reward (SR) to marijuana use and problems via affect lability and poor control. A 6-month prospective design was used in a sample of 2,270 young-adults (64% female). The hypothesized SP × SR interaction did not predict affect lability or poor control, but did predict use likelihood at baseline. At low levels of SR, SP was associated with an increased likelihood of abstaining, which was attenuated as SR increased. SP and SR displayed positive main effects on both affect lability and poor control. Affect lability and poor control, in turn, mediated effects on the marijuana outcomes. Poor control predicted both increased marijuana use and, controlling for use level, greater intensity of problems. Affect lability predicted greater intensity of problems, but was not associated with use level. There were few prospective effects. SR consistently predicted greater marijuana use and problems. SP however, exhibited both risk and protective pathways. Results indicate that SP is associated with a decreased likelihood of marijuana use. However, once use is initiated SP is associated with increased risk of problems, in part, due to its effects on both affect and behavioral dysregulation. (PsycINFO Database Record

A large number of compounds including lignin, phospholipids, pectin, DNA, mRNA, and proteins require methyl groups for their functionality. A detailed study of the expression and activities of two enzymes, adenosine kinase (ADK) and S-adenosylhomocysteine hydrolase (SAHH), which are both required for the maintenance and recycling of S-adenosylmethionine-dependent methylation in plants, was carried out. The abundance and tissue localization of ADK and SAHH transcripts and protein were monitored along with their enzyme activities in leaves, stems, buds, siliques, and roots of Arabidopsis. In all but roots and seed coats, the transcript abundance of ADK and SAHH fluctuated co-ordinately, matching changes in their protein and enzyme activities. To evaluate whether this expression pattern was associated with methyl recycling, the protein content and distribution of S-adenosylmethionine synthetase and phosphoethanolamine N-methyltransferase, a key methyltransferase involved in phospholipid synthesis, were investigated. These were found to accumulate in a pattern similar to ADK and SAHH. ADK and SAHH protein and transcript amounts were shown to fluctuate similarly in tissues accumulating lignin. Additionally, the amounts of ADK and SAHH mRNAs were also found at high levels in inflorescence meristems likely to support their higher rates of cell division. Thus, the results point to a co-ordinated and probably transcriptional regulation of these genes in most organs of Arabidopsis; SAHH abundance is distinctly higher in seeds and roots which suggests it may have a non-methyl-related role in these organs.

This study tested within-person associations between intoxication, negative affect, and self-control demands and two forms of self-control failure, interpersonal conflict, and neglecting responsibilities. Effortful control was hypothesised to act as a buffer, reducing individual susceptibility to these within-person effects. In contrast, reactivity was hypothesised to potentiate the within-person associations. 274 young adults aged 18-27 (56% women, 93% white) completed experience sampling assessments for up to 49 days over the course of 1.3 years. Results indicated independent within-person effects of intoxication, negative affect, and self-control demands on the outcomes. Hypothesised moderating effects of reactivity were not supported. Effortful control did not moderate the effects of self-control demands as expected. However, effortful control exhibited a protective effect when individuals were intoxicated or upset to reduce the likelihood of maladaptive behavioural outcomes.

Although it is well accepted that cytokinins (CKs) regulate processes such as leaf senescence and stomatal conductance, data on CKs in the canopy of mature trees are lacking in the literature. Here we report the first in situ sampling for determination of CKs in mature sugar maple (Acer saccharum) canopy layers. The upper canopy showed a distinct seasonal pattern in total CK content, while the lower canopy remained relatively unchanged.

Small local populations of Silene alba, a short-lived herbaceous plant, were sampled in 1994 and again in 1999. Sampling included estimates of population size and genetic diversity, as measured at six polymorphic allozyme loci. When averaged across populations, there was very little change between samples (about three generations) in population size, measures of within-population genetic diversity such as number of alleles or expected heterozygosity, or in the apportionment of genetic diversity within and among populations as measured by F(st). However, individual populations changed considerably, both in terms of numbers of individuals and genetic composition. Some populations doubled in size between samples, while others shrank by more than 75%. Similarly, expected heterozygosity and allele number increased by more than two-fold in individual populations and decreased by more than three-fold in others. When population-specific change in number and change in measures of genetic diversity were considered together, significant positive correlations were found between the demographic and genetic variables. It is speculated that some populations were released from the demographic consequences of inbreeding depression by gene flow.

Alcohol-related attentional biases are positively associated with drinking history and may represent a mechanism by which alcohol use behavior is maintained over time. This study was designed to address two unresolved issues regarding alcohol-related attention biases. Specifically, this study tested whether acute changes in positive and negative mood increase attentional biases toward alcohol cues and whether coping and enhancement drinking motives moderate these effects.Participants were 100 college students aged 18-25, who drank alcohol at least once in the last 90 days. In a 2 × 3 mixed design, participants were randomized to one of three mood conditions (neutral, negative, or positive) and completed visual-probe tasks pre- and post-mood-induction.Attentional biases toward alcohol cues were significantly associated with alcohol consumption among men, but not women. Although the mood manipulation was highly successful, attentional biases did not vary as a function of mood condition and hypothesized moderating effects of drinking motives were not significant.The largely null findings of the experiment are discussed in light of the fact that the visual probe task had poor reliability. Issues related to the reliability of visual-probe task are discussed, as more research is needed to evaluate and improve the psychometrics of this method.

Xylem-mobile Na+ in peas appears to have the attributes of a convenient marker for estimates of root biomass. This study examined the consistency and predictability of biomass-based, root to shoot Na+ delivery rates. In glasshouse experiments, xylem Na+ delivery was studied according to changing exogenous pressure regimes, time of day of xylem sap extraction, plant development, soil Na+ concentration and xylem sap extraction methods. At a given developmental stage, Na+ delivery in relation to root biomass was constant and independent of xylem water flux. This relationship held providing that collections were made for at least 60 min, the nature of xylem sap extraction (natural root pressure, vacuum or external pressure) was the same and Na+ concentration in the nutrient solution was constant and below 2.5 mM. A negative linear relationship was found between-biomass based Na+ delivery and development (degree days after emergence), with declining values likely caused by overestimates of viable root biomass. Likewise, in the field, Na+ delivery rates occurred predictably with soil Na+, as long as soil Na+ was not increased beyond 5-fold that of naturally occurring levels. Field biomass-based Na+ delivery was largely unaffected by changes in development from early flowering to late seed filling. If used within the defined methodological and developmental limits, Na+ delivery can be a valuable time and labour saving tool for calculating numerous root biomass characteristics, particularly in soil substrates that hamper accurate root recovery. Key words: Controlled conditions, field, Na+ uptake, pea, root biomass, xylem delivery

This study tested the effects of alcohol intoxication and physiological arousal on cognitive biases toward erotic stimuli and condoms. Ninety-seven heterosexual men were randomized to 1 of 6 independent conditions in a 2 (high arousal or control) × 3 (alcohol target BAC = 0.08), placebo, or juice control) design and then completed a variant of the Approach Avoidance Task (AAT). The AAT assessed reaction times toward approaching and avoiding erotic stimuli and condoms with a joystick. Consistent with hypotheses, the alcohol condition exhibited an approach bias toward erotic stimuli, whereas the control and placebo groups exhibited an approach bias toward condom stimuli. Similarly, the participants in the high arousal condition exhibited an approach bias toward erotic stimuli and the low arousal control condition exhibited an approach bias toward condoms. The results suggest that acute changes in intoxication and physiological arousal independently foster biased responding towards sexual stimuli and these biases are associated with sexual risk intentions.

Understanding the relationships between cell cycle and protein expression is critical to the optimisation of media and environmental conditions for successful commercial operation of animal cell culture processes. Using flow cytometry for the analysis of the early phases of synchronised batch cultures, the dependency of product expression on cell cycle related events has been evaluated in a recombinant CHO cell line. Although the production of recombinant protein is initially found to be cell cycle related, the maximum specific protein productivity is only achieved at a later stage of the exponential phase which also sees a maximum in the intracellular protein concentration. Subsequent work suggests that it is the batch phase/medium composition of cultures which is the major determinant of maximum specific productivity in this cell line. Furthermore the effect of the positive association between S phase and specific productivity is subordinate to the effect of batch phase/medium composition on the specific productivity of batch cultures.

A simple, rapid and reliable method has been developed for assessing the number and viability of cells, as well as cell size, in suspension culture by the use of flow cytometry. Propidium iodide exclusion is used for viability determination and fluorescent beads serve as an internal standard for cell enumeration. The main advantages of this method are its ability to handle a large number of samples with a high degree of precision and its specificity in detecting viable cells quantitatively in a heterogeneous culture of living and dead cells and debris. The method shows only a fraction of the variation found in the haemacytometer/trypan blue counting method due to its very low operator dependence. CHO - Chinese hamster ovary; FCS - Foetal calf serum; FS - Forward scatter light; MTT - 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide; NCS - newborn calf serum; PBS - Phosphate buffered saline; PI - Propidium iodide; SS - Side scatter light.

Apoptosis is a form of programmed cell death which exhibits highly distinctive morphology. Research activity in this area has increased substantially in recent years, primarily due to the realisation that disregulation of apoptosis is involved in the development of a number of pathological conditions, including cancer and AIDS. However, it is now clear that apoptosis also represents the dominant form of cell death during the culture of industrially important cell lines. This review focuses on the induction of apoptosis during industrial cell cultures as well as the effects of the apoptosis suppresser gene bcl-2 on cell survival in conditions relevant to bioreaction environments. We also present new data which demonstrates that bcl-2 can protect cells from apoptosis induced by oxygen deprivation, a finding which has important implications for large scale and intensive cultivation of cells. We also describe experiments which suggest that bcl-2 can reduce the specific nutrient consumption rate of cells.

Deficits in emotional and behavioral regulation figure prominently in etiological models of alcohol-related problems (Baker, Piper, McCarthy, Majeskie, & Fiore, 2004; Wiers et al., 2007). This study tests a model linking poor differentiation of emotion to alcohol-related problems via urgency. The sample consisted of 102 undergraduates between the ages 18 to 24 who reported moderate to heavy alcohol consumption. As hypothesized, negative urgency mediated the relationship between negative emotion differentiation and alcohol-related problems. However, contrary to hypothesis, positive urgency was not associated with either positive emotion differentiation or alcohol-related problems and the indirect effect of positive emotion differentiation via positive urgency was not significant. Instead, positive emotion differentiation exhibited a significant direct effect on alcohol-related problems. This study provides an initial examination of connections between specificity in labeling emotions, behavioral disinhibition, and problematic alcohol use. These findings suggest poor differentiation of negative emotion may foster impulsive behavior when negatively aroused. Whereas, impulsive behavior when positively aroused may reflect heightened sensitivity to positive reinforcement, which may not be related to reflective processes underlying emotion differentiation.

Both methyl jasmonate (MJ) and ethylene have been implicated in promoting senescence, but the specific roles of each and the mechanisms by which they act are not well known. We tested the possibility that MJ and ethylene interact to promote senescence. In sunflower seedlings, the ability of MJ to affect ethylene metabolism was investigated in hypocotyls, cotyledons, and leaves. 1-aminocylcopropane-1-carboxylic acid (ACC)-dependent ethylene production was promoted to different extents depending on the organ and the age of the tissue. Newly emerged hypocotyls were sensitive to MJ, but became desensitized as the cotyledons emerged. The cotyledons increased and peaked in MJ sensitivity from emergence to the production of the primary leaves. Leaves were found to be somewhat insensitive to MJ treatment compared to cotyledons at all ages tested. In cotyledons, MJ also promoted ACC and ethylene production. However the changes in ACC, and ACC-dependent ethylene production were not directly correlated with those in ethylene production with respect to MJ concentration or tissue age. Moreover, changes in ACC-dependent ethylene production did not correlate with in vitro ACC oxidase activity. We hypothesized that MJ affects ethylene production by increasing the spatial access of ACC to ACC oxidase perhaps through increased membrane permeability. Ethylene was not involved in the MJ-induced loss of chlorophyll. But the breakdown of cell integrity and cell membranes (estimated by monitoring conductivity of the solution that bathed the cotyledons) was greatly and synergistically promoted by the combination of MJ and ethylene. Promotion of membrane breakdown by MJ and ethylene could be inhibited by treatments with ethylene inhibitors (STS or CoCl2), and neither MJ nor ACC treatment alone could induce as much membrane breakdown as both together. We suggest that MJ and ethylene interact to accelerate some aspects of senescence in specific organs for nutrient remobilization for the benefit of the whole plant.

The abilities of various methods of oxygenation to meet the demands of high-cell-density culture were investigated using a spin filter perfusion system in a bench-top bioreactor. Oxygen demand at high cell density could not be met by sparging with air inside a spin filter (oxygen transfer values in this condition were comparable with those for surface aeration). Sparging with air outside a spin filter gave adequate oxygen transfer for the support of cell concentrations above 10(7) ml-1 in fully aerobic conditions but the addition of antifoam to control foaming caused blockage of the spinfilter mesh. Bubble-free aeration through immersed silicone tubing with pure oxygen gave similar oxygen transfer rates to that of sparging with air but without the problems of bubble damage and fouling of the spin filter. A supra-optimal level of dissolved oxygen (478% air saturation) inhibited cell growth. However, cells could recover from this stress and reach high density after reduction of the dissolved oxygen level to 50% air saturation.

Exposure of animal cells to intense hydrodynamic forces exerted in turbulent capillary flow, and by controiled agitation and aeration, resulted in preferential destruction of S and G(2) cells and the extent of destruction of these cells was dependent upon the intensity of the action. The loss of these cells was possibly due to their larger size. However, the appearance of large numbers of membrane-bound vesicular structures similar to apoptotic bodies as well as cells with low DNA stainability (in a sub-G(1) peak) suggested that the action of adverse hydrodynamic forces on these large cells may at least in part be to induce an apoptotic response. (c) 1995 John Wiley & Sons, Inc.

Insect cells have been propagated in monolayers in T-flasks or in suspension culture in spinner flasks, the latter being conducted over a range of spinner speeds. In both configurations, the cells were also infected with either wild or recombinant β-galactosidase baculovirus at MOI of 0.1, 1 and 10. The strength of both uninfected and infected cells was also measured by a micro-manipulation technique. No significant difference in growth rate was obtained between monolayer culture and suspension culture at the spinner rate which was optimum for growth. This optimum was quite sharp. At the lowest speeds cells settled, whilst above the optimum speed the spinner action led to significant cell damage. The maximum infectivity was obtained at this optimum speed which also gave maximum survival after infection. There were significant changes of cell survival and infection, even over relatively small changes of speed, and presumably energy dissipation rate. As changes in growth in turbine-agitated bioreactors have been shown to be much less, even when the energy inputs varied by two orders of magnitude, these findings throw doubt on the usefulness of spinner flasks for assessing “shear” sensitivity of cell lines. The percentage of infected cells and β-galactosidase production were significantly lower in the monolayer culture compared to that in the suspension culture at MOI values below 10 pfu/cell. This difference is explained as being due to the reduced movement of released virus particles from infected to non-infected cells in the T-flasks.

The neural degeneration caused by spinal cord injury leaves a cavity at the injury site that greatly inhibits repair. One approach to promoting repair is to fill the cavity with a scaffold to limit further damage and encourage regrowth. Injectable materials are advantageous scaffolds because they can be placed as a liquid in the lesion site then form a solid in vivo that precisely matches the contours of the lesion. Fibrin is one type of injectable scaffold, but risk of infection from blood borne pathogens has limited its use. We investigated the potential utility of salmon fibrin as an injectable scaffold to treat spinal cord injury since it lacks mammalian infectious agents and encourages greater neuronal extension in vitro than mammalian fibrin or Matrigel®, another injectable material. Female rats received a T9 dorsal hemisection injury and were treated with either salmon or human fibrin at the time of injury while a third group served as untreated controls. Locomotor function was assessed using the BBB scale, bladder function was analyzed by measuring residual urine, and sensory responses were tested by mechanical stimulation (von Frey hairs). Histological analyses quantified the glial scar, lesion volume, and serotonergic fiber density. Rats that received salmon fibrin exhibited significantly improved recovery of both locomotor and bladder function and a greater density of serotonergic innervation caudal to the lesion site without exacerbation of pain. Rats treated with salmon fibrin also exhibited less autophagia than those treated with human fibrin, potentially pointing to amelioration of sensory dysfunction. Glial scar formation and lesion size did not differ significantly among groups. The pattern and timing of salmon fibrin's effects suggest that it acts on neuronal populations but not by stimulating long tract regeneration. Salmon fibrin clearly has properties distinct from those of mammalian fibrin and is a beneficial injectable scaffold for treatment of spinal cord injury.

Because of concern for cell damage, very low agitation energy inputs have been used in industrial animal cell bioreactors, typical values being two orders of magnitude less than those found in bacterial fermentations. Aeration rates are also very small. As a result, such bioreactors might be both poorly mixed and also unable to provide the higher oxygen up-take rates demanded by more intensive operation. This paper reports experimental studies both of K( L ) a and of mixing (via pH measurements) in bioreactors up to 8 m(3) at Wellcome and of scaled down models of such reactors at Birmingham. Alongside these physical measurements, sensitivity of certain cell lines to continuously controlled dO(2) has been studied and the oxygen up-take rates measured in representative growth conditions. An analysis of characteristic times and mixing theory, together with other recent work showing that more vigorous agitation and aeration can be used especially in the presence of Pluronic F-68, indicates ways of improving their performance. pH gradients offer a special challenge.

A simple, rapid and reliable method has been developed for assessing the number and viability of cells, as well as cell size, in suspension culture by the use of flow cytometry. Propidium iodide exclusion is used for viability determination and fluorescent beads serve as an internal standard for cell enumeration. The main advantages of this method are its ability to handle a large number of samples with a high degree of precision and its specificity in detecting viable cells quantitatively in a heterogeneous culture of living and dead cells and debris. The method shows only a fraction of the variation found in the haemacytometer/trypan blue counting method due to its very low operator dependence. CHO - Chinese hamster ovary; FCS - Foetal calf serum; FS - Forward scatter light; MTT - 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide; NCS - newborn calf serum; PBS - Phosphate buffered saline; PI - Propidium iodide; SS - Side scatter light.

Using differences between the alpine and prairie ecotypes of Stellaria longipes, we investigated whether characteristic levels of phenotypic plasticity could be explained in terms of either Grime's C-S-R model or Taylor and Aarssen's specialization hypothesis. Seven populations of S. longipes were located along an elevational gradient, and fine-scale differentiation between the alpine and prairie forms was quantified genetically and morphologically. Analysis of eight enzyme systems revealed two distinct clusters separating high-elevation populations from low-elevation populations. Morphologically, means and plasticities of traits previously used to describe the tundra ecotype showed parallel population grouping to that of the isozyme analysis. Analysis of environmental parameters showed that growth change and amount of phenotypic plasticity had significant associations with increased wind and temperature stress at high elevations and high interspecific competition at low elevations. This is consistent with the idea that the parallel patterns of separation observed for isozymes, morphology, and plasticity are a result of selection pressures consistent with the C-S-R model. In reciprocal transplants, tundra plants with low plasticity were selected against in a prairie environment. However, no clear advantage was observed for either ecotype in the alpine environment. The high plasticity of the prairie ecotype is likely adaptive for competitive habitats and does not bear a cost of low performance in the unfavorable alpine habitat, as predicted by the specialization hypothesis. The relatively poor performance of the alpine ecotype may reflect a restriction rather than specialization to stressful alpine environments. However, selection for the tundra ecotype in its native habitat may have been detected in experiments carried out over a longer period than those of this study.

Morphological relationships were investigated among diploidStellaria porsildii, polyploidS. longipes, and diploidS. longifolia. Canonical discriminant analysis, based on a priori assumptions to maximize differences among groups, showed thatS. longipes clusters equally distant between the two diploid species along an axis connecting the diploids' centroids, but it differs along an axis perpendicular to this axis. The intermediacy along the former axis is evidence thatS. longipes is an amphiploid derived fromS. longifolia andS. porsildii. The divergence along the latter axis may be attributable to adaptively valuable heterotic traits which were retained following amphidiploidization. The only morphological discontinuity occurred between the two diploids, whereas the morphological range ofS. longipes overlapped the range of both diploids forming a continuum. The lack of discrete clusters is likely due to hybridization and introgression withS. longifolia on one hand, and convergence of traits betweenS. longipes var.monantha andS. porsildii on the other. High a posteriori assignments in classificatory discriminant analysis supports the separation ofS. longipes var.monantha from otherS. longipes specimens. AlthoughS. longipes var.monantha grouped close toS. porsildii, the two groups separate based on leaf shape traits. Overall results support, firstly, the hypothesis thatS. porsildii is a diploid parent species which by hybridizing withS. longifolia gave rise to polyploidS. longipes. Secondly, results suggest thatS. longipes var.monantha converged morphologically towardsS. porsildii relatively recently due to ecological specialization, and merits distinction at least as a variety ofS. longipes.

Industrial Research Ltd (IRL) have been developing a unique diaphragm based pressure wave generator technology for pulse tube and Stirling cryocoolers. Our system uses a metal diaphragm to separate the clean cryocooler gas circuit from a conventionally lubricated mechanical driver, thus producing a clean pressure wave with a long life drive that does not require the precision manufacture and associated costs of large linear motors. The first successful diaphragm pressure wave generator produced 3.2 kW of acoustic power at an electro‐acoustic efficiency of 72% with a swept volume of 200 ml and a prototype has now accumulated over 2500 hours running. This paper describes recent developments in the technology. To explore scaling, a small diaphragm pressure wave generator with a swept volume of 20 ml has been constructed and has delivered 454 W of acoustic power at an electro‐acoustic efficiency of 60%. Improvements have been made to the hydraulic force amplifier mechanism for driving the diaphragms resulting in a cheaper and lighter mechanism than the mechanical linkage originally used. To meet a customer’s specific requirements, the 200 ml pressure wave generator’s stroke was extended to achieve 240 ml of swept volume thereby increasing its acoustic power delivery to 4.1 kW without compromising efficiency.

Understanding the relationships between cell cycle and protein expression is critical to the optimisation of media and environmental conditions for successful commercial operation of animal cell culture processes. Using flow cytometry for the analysis of the early phases of synchronised batch cultures, the dependency of product expression on cell cycle related events has been evaluated in a recombinant CHO cell line. Although the production of recombinant protein is initially found to be cell cycle related, the maximum specific protein productivity is only achieved at a later stage of the exponential phase which also sees a maximum in the intracellular protein concentration. Subsequent work suggests that it is the batch phase/medium composition of cultures which is the major determinant of maximum specific productivity in this cell line. Furthermore the effect of the positive association between S phase and specific productivity is subordinate to the effect of batch phase/medium composition on the specific productivity of batch cultures.

Centrifugal elutriation was used to produce cell cycle enrichedfractions of four commercially relevant recombinant cell lines,chosen to allow for variation in properties due to construct,expression system and parent cell type, from normally growingheterogeneous batch cultures. As these fractions had identicalculture histories and had not been subjected to any insult orstress which was likely to have adversely affected cellularmetabolism, they were ideal for further study of cellularproperties. Specific productivity, cell size and cell cyclestate of replicate elutriated fractions were measured for eachcell line. Results showed that cell size was the major cellulardeterminant of productivity for all cell lines examined. Productformation was not restricted to any particular cell cycle phaseand in all cases, production occurred irrespective of cell cyclephase. Specific productivity was lowest when the majority ofcells in the fraction were G(1), intermediate when themajority of cells in the fraction were S phase and greater whenthe majority of cells in the fraction were in G(2)/M. However, the evidence suggests that size is the major cellulardeterminant of productivity; the apparent relationship betweencell cycle and productivity is secondary and can simply beascribed to the increasing size of cells as they progress thoughthe cell cycle. Thus, in addition to cell density and viabilitycell size is the cellular parameter which should be incorporatednot only into mathematical models of recombinant mammalian cellproduction processes but also into process monitoring andcontrol strategies.

The importance of cell cycle analysis in cell culture development has been widely recognised. Whether such analysis is useful in indicating future performance of high cell density culture is uncertain. Using flow cytometric approach to address this question, we utilised the fraction of cells in the S phase to control specific growth rate and productivity in spin filter perfusion cultures and found a significant increase in the accumulated interferon-gamma over that obtained from the nutrient-based controlled fed culture. While a general decrease with time exists in both percentage of S phase cells and specific growth rate, a clear oscillatory behaviour of both parameters is found in perfusion cultures.