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Molecular dynamics simulations were performed of the adsorption of methylene blue (MB) on model beidellite, montmorillonite, and muscovite mica surfaces, using a previously determined empirical force field developed for dioctahedral clays. The simulations show that the adsorption of MB on mineral surfaces can result in a variety of configurations, including single and double layers of MB parallel to the basal surface, and irregular clusters. The d(001) values of ~12.3 and ~15.7 Å are assigned to dry phases with parallel single and double layers of MB, respectively, in agreement with X-ray studies. At intermediate MB loadings, stacks inclined to basal surfaces are formed. The stacks of MB ions inclined by 65–70° relative to the (001) plane of muscovite are not found on dry surfaces, in contrast to previous studies. Configurations similar to those proposed by others form spontaneously in the presence of H2O, but the ions in the model systems are not quite as ordered and not ordered in exactly the same way as the ones previously described, and they display a mobility that is not compatible with strict atomic order. The formation of a triple layer of H2O interspersed with ions may occur in the interlayer. Overall, the results of the simulations confirm that the MB-ion method must be used with great caution in surface-area determinations, because of the multiplicity of possible configurations. At the same time, the ability for adsorption to occur as either single or multiple MB layers is useful to determine cation-exchange capacity over a wide range of surface-charge densities.
There are phenomenological similarities between social anxiety disorder (SAD) and posttraumatic stress disorder, such as a provoking aversive event, posttraumatic stress symptoms (e.g. intrusions) in response to these events and deficient (context-dependent) fear conditioning processes. This study investigated the neural correlates of context-dependent extinction recall and fear renewal in SAD, specifically in patients with intrusions in response to an etiologically relevant aversive social event.
Methods
During functional magnetic resonance imaging a two-day context-dependent fear conditioning paradigm was conducted in 54 patients with SAD and 54 healthy controls (HC). This included fear acquisition (context A) and extinction learning (context B) on one day, and extinction recall (context B) as well as fear renewal (contexts C and A) one day later. The main outcome measures were blood oxygen level-dependent responses in regions of interest and skin conductance responses.
Results
Patients with SAD showed reduced differential conditioned amygdala activation during extinction recall in the safe extinction context and during fear renewal in the acquisition context compared to HC. Patients with clinically relevant intrusions moreover exhibited hypoactivation of the ventromedial prefrontal cortex (vmPFC) during extinction learning, extinction recall, and fear renewal in a novel context, while amygdala activation more strongly decreased during extinction learning and increased during fear renewal in the acquisition context compared with patients without intrusions.
Conclusions
Our study provides first evidence that intrusions in SAD are associated with similar deficits in context-dependent regulation of conditioned fear via the vmPFC as previously demonstrated in posttraumatic stress disorder.
One of the major challenges in clinical psychiatry remains the absence of well established objective measures of symptoms’ severity. Clinical insights are mainly provided through keen behavioral observation and subjective questionnaires and scales.
Objectives
The aim of this paper is to predict depression severity through speech using the features extracted from the speech as provided by participants during a semi-structured dialogue with a virtual avatar.
Methods
We use data from a subset of the DAICWOZ dataset consisting in 142 dialogues between participants and a virtual avatar during which the avatar uses several prompts to maintain a conversation with the participant. The avatar uses prompts involving the topics of travel, dream jobs, and memorable experiences. From the speech generated from the dialogue, we extract participant utterances separated by prompt and extract features from the three sets of transcripts. We extract content features from the transcript and acoustic features from the excerpt corresponding to the speech from the participant for the prompt in question.We perform regression experiments on the PHQ8 items using the features extracted from each set of transcripts. Furthermore, we combine the features extracted from each set of transcripts and compute partial spearman correlations between them and the PHQ8 items using gender as a covariate.
Results
With our best regression model we obtain an R2 of 0.1, explaining 10% of the variance in the PHQ total score. Additionally, we obtain a mean absolute error of 1.25, suggesting that the regressor can detect with more or less precision clinically meaningful differences in depression severity between participants. Partial correlations between the total score and the features show significant correlations between features dependent on the amount of speech generated by each participant, along with the complexity of syntactic structures used.
Conclusions
Automatic analysis of spontaneous speech could help with the detection and monitoring of signs of depression. By combining the use of this technology with timely intervention strategies for instance provided by a virtual agent it could contribute to timely prevention.
Disclosure of Interest
A. König: None Declared, M. Mina Employee of: ki:elements GmbH, S. Schäfer Employee of: ki:elements GmbH, N. Linz Shareolder of: ki:elements GmbH, Employee of: ki:elements GmbH, J. Tröger Shareolder of: ki:elements GmbH, Employee of: ki:elements GmbH
Difficulties in the context-dependent modulation of conditioned fear are known for posttraumatic stress disorder and may explain the occurrence of intrusive memories in safe contexts. The current study therefore investigated if reduced context-dependent modulation of conditioned fear and its underlying neural circuitry constitute risk factors for the development of analog intrusions in response to an experimental trauma.
Methods
Eighty-five healthy women participated in the trauma film paradigm to investigate the development of analog intrusions as well as explicit memory for an experimental trauma after one week and three months, respectively. Before, participants underwent a context-dependent fear conditioning paradigm during functional magnetic resonance imaging with fear acquisition in context A and extinction training in context B on a first day, as well as extinction recall in context B and fear renewal in a novel context C one day later. Skin conductance responses (SCRs) and blood oxygen level dependent responses were main outcome measures.
Results
In addition to stronger fear acquisition in context A, stronger conditioned fear responses in the safe context B, as indicated by stronger conditioned SCRs or stronger activation of fear expressing regions during extinction learning and recall, predicted the development of long-term analog intrusions.
Conclusions
Stronger fear responses in safe and danger contexts were risk factors for the development of long-term analog intrusions and point to decontextualized fear memories and difficulties in the context-dependent modulation of conditioned fear. Altered fear conditioning processes and reduced storage of contextual information may cause the occurrence of fear independent of context.
OBJECTIVES/GOALS: Glioblastomas (GBMs) are heterogeneous, treatment-resistant tumors that are driven by populations of cancer stem cells (CSCs). In this study, we perform an epigenetic-focused functional genomics screen in GBM organoids and identify WDR5 as an essential epigenetic regulator in the SOX2-enriched, therapy resistant cancer stem cell niche. METHODS/STUDY POPULATION: Despite their importance for tumor growth, few molecular mechanisms critical for CSC population maintenance have been exploited for therapeutic development. We developed a spatially resolved loss-of-function screen in GBM patient-derived organoids to identify essential epigenetic regulators in the SOX2-enriched, therapy resistant niche. Our niche-specific screens identified WDR5, an H3K4 histone methyltransferase responsible for activating specific gene expression, as indispensable for GBM CSC growth and survival. RESULTS/ANTICIPATED RESULTS: In GBM CSC models, WDR5 inhibitors blocked WRAD complex assembly and reduced H3K4 trimethylation and expression of genes involved in CSC-relevant oncogenic pathways. H3K4me3 peaks lost with WDR5 inhibitor treatment occurred disproportionally on POU transcription factor motifs, required for stem cell maintenance and including the POU5F1(OCT4)::SOX2 motif. We incorporated a SOX2/OCT4 motif driven GFP reporter system into our CSC cell models and found that WDR5 inhibitor treatment resulted in dose-dependent silencing of stem cell reporter activity. Further, WDR5 inhibitor treatment altered the stem cell state, disrupting CSC in vitro growth and self-renewal as well as in vivo tumor growth. DISCUSSION/SIGNIFICANCE: Our results unveiled the role of WDR5 in maintaining the CSC state in GBM and provide a rationale for therapeutic development of WDR5 inhibitors for GBM and other advanced cancers. This conceptual and experimental framework can be applied to many cancers, and can unmask unique microenvironmental biology and rationally designed combination therapies.
The mounting evidence for effective delivery of psychological interventions by non-specialists in low- and middle-income settings has led to a rapid expansion of mental health and psychosocial support trainings globally. As such, there is a demand for strategies on how to train and implement these services to attain adequate quality. This study aims to evaluate the added value of a competency-driven approach to training of facilitators for a group intervention for children with severe emotional distress in Lebanon.
Methods
In a controlled before and after study, 24 trainees were randomly allocated to participate in either a competency-driven training (CDT) or training-as-usual (TAU) (1 : 1) for a psychological intervention for children with severe emotional distress. We assessed the change in demonstrated competencies, using standardised role-plays, before and after the training. Measures included the 13-item Working with children-Assessment of Competencies Tool (WeACT), the 15-item ENhancing Assessment of Common Therapeutic factors (ENACT) and the 6-item Group facilitation: Assessment of Competencies Tool (GroupACT). The trainer in the experimental arm used pre-training and during training competency assessment scores to make real-time adjustment to training delivery. Due to COVID-19 pandemic restrictions, all activities were done remotely.
Results
CDT resulted in significantly better outcomes on increasing competencies on the WeACT (repeated measures analysis of variance; F(1, 22) = 6.49, p < 0.018) and on the GroupACT (Mann–Whitney U = 22, p < 0.003), though not statistically significant on the ENACT. There is no significant between-group difference on the reduction of harmful behaviours, mainly because both forms of training appear equally successful in eliminating such behaviours.
Conclusions
This proof-of-concept study demonstrates the potential of CDT, using standardised assessment of trainee competencies, to contribute to better training outcomes without extending the duration of training. CDT can result in up to 18% greater increase in adequate competency, when compared to TAU. The study also yields recommendations for further enhancing the benefits of competency-driven strategies. A fully powered trial is needed to confirm these findings.
Supplier of system components face the challenge of customer requirements influencing the property level functional integral product architectures. For this, solution approaches focusing on the re-use of pre-engineered part variants are not applicable. However, to generate a valid product structure, customer-specific properties have to fit modelled product knowledge. Therefore, the approach models a reference class structure and analysis compatibilities on the property level for customer specific inputs concerning explicit product knowledge and constraints.
The consequences of Childhood trauma (CT) become increasingly apparent. The available data suggest that (1) CT is related to persisting alterations of HPA activity, (2) CT is related to psychopathology in patients with substance use disorders (SUD), and (3) alterations of HPA activity are related to craving and psychopathology. However, none of the existing studies have tried to integrate these different perspectives.
Methods:
We assessed anxiety (STAI), depression (BDI) and craving (OCDS-D) in a consecutive sample of 42 patients with alcohol dependence (37% female, 63% male) on day 1 (t1) and day 14 (t2) after their admission to a detoxification unit. Morning plasma levels of cortisol and ACTH were assessed and a standard dexamethasone test (DST) was performed (t2). Finally, the Childhood Trauma Questionnaire was administered.
Results:
At t1, cortisol levels correlated significantly with anxiety (r=.34*) and sexual abuse (r=.38*). An inverse relationship was found between ACTH levels and both, emotional abuse and emotional neglect (t1: r=-.33*, r=-.39*; t2: r=-.32*, r=-.51**). This relationship persisted when controlling for depression. Craving was related to anxiety and depression (t1: r=.53**, r=.60**; t2: r=.39*, r=.35*), but not to cortisol or ACTH levels. No relationships existed between CT and the DST outcome.
Conclusions:
Our results give first evidence that CT is related to changes of the HPA activity in SUD patients, but they could not be further clarified by the DST. Psychopathology was related to both, early trauma and craving. Future studies should try to further examine these complex relationships.
Injection drug users (IDUs) frequently suffer from somatic and mental co-morbidity. The effects of different opioid maintenance protocols on these parameters have not been systematically studied yet.
Methods:
This study was conducted as a 12-month open-label multi-centre randomised controlled trial to test a heroin- vs. methadone based protocol.
Results:
515 patients were randomised to the heroin-assisted and 500 to the methadone-assisted treatment program. Baseline scores were as follows: OTI-HSS 19.0 (±5.2), BMI 22.6 (±3.5), pathologic electro-/echocardiogram 20.4% (n=582) / 13.9% (n=491), positive HBV-, HCV- and HIV-serology 65.7% (n=863) / 86.5% (n=855) / 9.2% (n=951), positive tuberculin test 9.1% (n=318), KPS 71.4 (±12.9), Global Severity Index (GSI; SCL-90-R) 69.2 (±10.6), GAF 53.6 (±11.7) (all parameters not significant between treatment groups). Improvement after 12 months of treatment differed significantly between treatment groups (heroin vs. methadone): OTI-HSS 8.1 (±5.2) vs. 10.6 (±6.4), BMI 24.5 (±4.3) vs. 23.7 (±4.1), KPS 78.2 (±12.8) vs. 74.2 (±13.3), GSI 58.6 (±13.7) vs. 62.0 (±13.2), GAF 63.0 (±13.3) vs. 56.2 (±15.0) (ANOVA, all p=.000). The frequency of pathologic echocardiograms after 12 months was significantly lower in the heroin compared to the methadone group. Within the heroin group, completers benefited stronger than drop-outs. The remaining parameters did not differ between baseline and 12 months and between treatment groups.
Conclusion:
Integration of severe injection drug users either in methadone or heroin assisted maintenance treatment has positive effects on most change sensitive physical and mental variables. In this patient group heroin assisted treatment showed superior results compared to methadone.
Treatment of cocaine dependence focuses on achieving abstinence and reducing problems associated to cocaine use. Despite extensive research and clinical experience, no “gold standard” has emerged from the different treatment options that have been researched. In general, research has shown that the evidence level for the efficacy of psychosocial interventions is higher than for pharmacologic interventions. With respect to psychosocial interventions, the evidence shows that all those interventions studied show efficacy to some extent, without greater differences in efficacy.
With respect to the pharmacologic options, none of the tested drugs have shown sufficient evidence to clearly be indicated in the treatment of cocaine dependence. Several substances have so far only been tested in smaller descriptive studies or pilot trials and will have to be studied in larger controlled trials. The substance presently with the highest level of evidence is disulfiram, and its effect has been shown to be independent of concomitant alcohol use. Of the substances that find themselves in the pilot stage and need to be confirmed by larger trials, the antidepressant reboxetine and the antiepileptic topiramate can be considered as two very promising ones. Of great interest has been the development of a cocaine vaccine. This vaccine leads to the production of cocaine antibodies, which in turn make cocaine metabolites inactive. A randomised controlled study showed the vaccine to produce cocaine antibodies in humans. A recent open-label study resulted in a significantly higher likelihood for cocaine free urines among vaccinated subjects, so that results are encouraging.
Studies have shown that mental health risks related to military deployment depend on specific risk factors. Especially stressful experiences (SE) and lack of social support (SS) have been associated with deployment-related increases in mental disorders. Less is known about difficulties in emotion regulation (DER) in this context despite their well-known importance for the development and maintenance of mental disorders. To date, the number of prospective studies investigating the role of these potential risk factors for deployment-related psychopathology is limited.
Objective
To investigate risk factors for deployment-related increases in symptoms of common mental disorders.
Aim
To investigate associations between SE, SS and DER, and deployment-related increases in PTSD, major depression (MD) and alcohol use disorder (AUD) symptoms.
Methods
358 male soldiers were assessed before and 12 months following deployment using standardized diagnostic interviews (CIDI) and embedded questionnaires. Outcome measures were the number of PTSD, MD and AUD symptoms reported for the preceding 12 months at follow-up. Analyses were adjusted for baseline symptoms.
Results
SE (incidence risk ratio (IRR)):1.06, p>0.001), SS (IRR:0.98, p=0.034) and DER (IRR:1.04, p=0.009) independently predicted increases in PTSD symptoms. SE (IRR:1.04, p=0.004) and SS (IRR:0.98, p=0.022) also predicted increases in MD symptoms. Increase in AUD symptoms was not predicted by SE, SS or DER, but by increase in PTSD symptoms (IRR:1.02, p=0.029).
Conclusions
Findings support the role of SE, SS and DER as risk factors for deployment-related disorders, particularly for PTSD symptoms. This knowledge might help to identify high-risk individuals and to develop targeted interventions.
This article synthesises the results of a large international study on primary care (PC), the QUALICOPC study.
Background:
Since the Alma Ata Declaration, strengthening PC has been high on the policy agenda. PC is associated with positive health outcomes, but it is unclear how care processes and structures relate to patient experiences.
Methods:
Survey data were collected during 2011–2013 from approximately 7000 PC physicians and 70 000 patients in 34, mainly European, countries. The data on the patients are linked to data on the PC physicians within each country and analysed using multilevel modelling.
Findings:
Patients had more positive experiences when their PC physician provided a broader range of services. However, a broader range of services is also associated with higher rates of hospitalisations for uncontrolled diabetes, but rates of avoidable diabetes-related hospitalisations were lower in countries where patients had a continuous relationship with PC physicians. Additionally, patients with a long-term relationship with their PC physician were less likely to attend the emergency department. Capitation payment was associated with more positive patient experiences. Mono- and multidisciplinary co-location was related to improved processes in PC, but the experiences of patients visiting multidisciplinary practices were less positive. A stronger national PC structure and higher overall health care expenditures are related to more favourable patient experiences for continuity and comprehensiveness. The study also revealed inequities: patients with a migration background reported less positive experiences. People with lower incomes more often postponed PC visits for financial reasons. Comprehensive and accessible care processes are related to less postponement of care.
Conclusions:
The study revealed room for improvement related to patient-reported experiences and highlighted the importance of core PC characteristics including a continuous doctor–patient relationship as well as a broad range of services offered by PC physicians.
Mothers’ return to work and childcare providers’ support for feeding expressed human milk are associated with breast-feeding duration rates in the USA, where most infants are regularly under non-parental care. The objective of the present study was to explore Florida-based childcare centre administrators’ awareness and perceptions of the Florida Breastfeeding Friendly Childcare Initiative.
Design
Semi-structured interviews were based on the Consolidated Framework for Implementation Research and analysed using applied thematic analysis.
Setting
Childcare centre administrators in Tampa Bay, FL, USA, interviewed in 2015.
Participants
Twenty-eight childcare centre administrators: female (100 %) and Non-Hispanic White (61 %) with mean age of 50 years and 13 years of experience.
Results
Most administrators perceived potential implementation of the Florida Breastfeeding Friendly Childcare Initiative as simple and beneficial. Tension for change and a related construct (perceived consumer need for the initiative) were low, seemingly due to formula-feeding being normative. Perceived financial costs and relative priority varied. Some centres had facilitating structural characteristics, but none had formal breast-feeding policies.
Conclusions
A cultural shift, facilitated by state and national breast-feeding-friendly childcare policies and regulations, may be important for increasing tension for change and thereby increasing access to breast-feeding-friendly childcare. Similar to efforts surrounding the rapid growth of the Baby Friendly Hospital Initiative, national comprehensive evidence-based policies, regulations, metrics and technical assistance are needed to strengthen state-level breast-feeding-friendly childcare initiatives.
The alteration and transformation behaviour of Ceca smectite in two acid and saline solutions (NaCl and KCl) was studied in batch experiments. This type of smectite is proposed as potential backfill material for nuclear waste storage sites. The initial solution was enriched with 500 ppm of U, Th and Eu. The evolution of pH and solution concentrations were measured over a period of 25 months. The mineralogical and chemical evolution of the clays was also studied. X-ray diffraction revealed a significant loss of diffraction intensity and the clays became amorphous to Xrays with increasing reaction time. Deconvolution of the XRD data indicated a continuous collapse of the smectite layers but no illitization. Infrared spectroscopy revealed unchanged smectite spectra at the end of the experiment. Thorium precipitated as amorphous ThO2, but showed an incipient crystallization after 500 days. The Th, Eu and U were neither adsorbed onto the clays nor incorporated into a secondary phase.
The alteration and transformation behaviour of the Tertiary Hammerschmiede Smectite and the Jurassic Opalinus Shale in an alkaline solution was studied in column experiments. The Hammerschmiede Smectite is proposed as potential backfill material and the Opalinus Shale as host rock for the Swiss low-level nuclear waste storage site. Over a period of 18 months, the evolution of permeability, pH and solution concentrations were measured. After the experiment, the columns were cut into pieces to study the mineralogical and the chemical evolution of the clays. X-ray diffraction (XRD) revealed no significant appearance or disappearance of diffraction peaks at the end of the experiments. The scanning electron micrographs of the clays revealed that both clays exhibited a precipitation zone, which extends from 0 to 2 cm below the infiltration surface. Both clays showed significant differences in the evolution of pH and hydraulic conductivity. The solution front crossed the Opalinus Shale column entirely after only 11 weeks and the initial values for K+ and Na+ were conserved in the solution. For both clays, the salt concentrations in the percolating fluids mirror the evolution of pH.
Active participation in social activities is important for the wellbeing of older adults. This study explored benefits of active social engagement by evaluating whether relationships that comprise active involvement (e.g. co-engagement in activities) bring more social benefits (i.e. social support, companionship, positive social influence) than other relationships that do not involve co-engagement. A total of 133 adults ages 60 years and older living in a rural Midwestern city in the United States of America were interviewed once and provided information on 1,740 social network members. Among 1,506 social relationships in which interactions occurred at least once a month, 52 per cent involved engagement in social activities together and 35 per cent involved eating together regularly. Results of the generalised linear mixed model showed that relationships involving co-engagement were significantly more likely to also convey social support (i.e. emotional, instrumental, informational), companionship and social influence (encouragement for healthy behaviours) than relationships that do not involve co-engagement. Having more network members who provide companionship was associated with higher sense of environmental mastery, positive relations with others and satisfaction with social network. Interventions may focus on maintaining and developing such social relationships and ensuring the presence of social settings in which co-engagement can occur. Future research may explore whether increasing co-engagement leads to an enhanced sense of companionship and psychological wellbeing.
We evaluate the variability in basal friction for Kronebreen, Svalbard, a fast-flowing tidewater glacier. We invert 3 years (2013–15) of surface velocities at high temporal resolution (generally 11 days), to estimate the changing basal properties of the glacier. Our results suggest that sliding behaviour of Kronebreen within a year is primarily influenced by changes in water input patterns during the meltwater season and basal friction is highly variable from a year to another. At present, models usually employ parameterisations to encompass the complex physics of glacier sliding by mathematically simulate their net effect. For such ice masses with strong seasonal variations of surface melt, the spatio-temporal patterns of basal friction imply that it is neither possible nor appropriate to use a parameterisation for bed friction that is fixed in space and/or time, at least in a timescale of a few years. Basal sliding may not only be governed by local processes such as basal topography or summer melt, but also be mediated by factors that vary over a larger distance and over a longer time period such as subglacial hydrology organisation, ice-thickness changes or calving front geometry.
Breast-feeding initiation rates have increased in the USA; however, maintenance of breast-feeding for recommended durations is low. The objective of the present study was to identify factors that may facilitate breast-feeding for longer durations among first-time mothers, including physiological and social experiences and changes in maternal perceptions.
Design
Survival analysis and linear regression methods were used to explore the relationship between experiences and breast-feeding duration, and the possible mediating effect of changes in maternal perceptions.
Setting
Secondary data from the Infant Feeding Practices Study II, conducted in the USA between 2005 and 2007.
Subjects
Data from 762 first-time mothers who ever breast-fed were analysed.
Results
Experiencing trouble with baby’s latch, problems with milk flow/supply and painful breast-feeding were significantly associated with breast-feeding duration (64, 26 and 36 % shorter duration, respectively). Meanwhile, positive changes in perception with respect to breast-feeding self-efficacy, opinion about infant feeding and belief about breast milk were associated with 16–27 % longer duration. Furthermore, changes in perception were observed to partially mediate the impact of physiological experiences on breast-feeding duration.
Conclusions
Perceptions of breast-feeding self-efficacy, beliefs and opinions can change over time and are influenced by breast-feeding experiences. The combined effect of experience and perception plays a key role in influencing breast-feeding duration. Future research should explore interventions to maintain or improve these perceptions while accounting for physiological experiences to support breast-feeding for recommended durations among first-time mothers.
This article explores long head movement configurations in Breton. Its purpose is twofold. First it contributes to existing work by demonstrating that Breton long head movement is motivated by information structure. The operation of general economy principles, made sensitive to information structure, determines many of the properties of the Breton construction. Secondly, it is argued that the derivation of the Breton construction does not involve movement per se; minimality conditions on movement are not central to the derivation. Instead, the remaining properties of the construction are attributed to a semantic property of tense-aspect markers which is represented at the LF interface. This work bears on the issue of how to model the interpretive dependency between auxiliaries and main verbs and raises questions concerning the interaction between the stylistic component, information structure, and the LF interface.