Indirect daylight oxidative degradation of polyethylene microplastics by a bio-waste modified TiO2-based material

Microplastics are recognized as an emerging critical issue for the environment. Here an innovative chemical approach for the treatment of microplastics is proposed, based on an oxidative process that does not require any direct energy source (irradiation or heat). Linear low-density polyethylene (LLDPE) was selected as target commodity polymer, due to its widespread use, chemical inertness and inefficient recycling. This route is based on a hybrid material coupling titanium oxide with a bio-waste, rosin, mainly constituted by abietic acid, through a simple sol-gel synthesis procedure. The ligand-to-metal charge transfer complexes formed between rosin and Ti4+ allow the generation of reactive oxygen species without UV irradiation for its activation. In agreement with theorical calculations, superoxide radical ions are stabilized at ambient conditions on the surface of the hybrid TiO2. Consequently, an impressive degradation of LLDPE is observed after 1 month exposure in a batch configuration under indirect daylight, as evidenced by the products revealed by gas chromatography-mass spectrometry analysis and by chemical and structural modifications of the polymer surface. In a context of waste exploitation, this innovative and sustainable approach represents a promising cost-effective strategy for the oxidative degradation of microplastics, without producing any toxic by-products.

Hybrid Hemp Particles as Functional Fillers for the Manufacturing of Hydrophobic and Anti-icing Epoxy Composite Coatings

The development of hydrophobic composite coatings is of great interest for several applications in the aerospace industry. Functionalized microparticles can be obtained from waste fabrics and employed as fillers to prepare sustainable hydrophobic epoxy-based coatings. Following a waste-to-wealth approach, a novel hydrophobic epoxy-based composite including hemp microparticles (HMPs) functionalized with waterglass solution, 3-aminopropyl triethoxysilane, polypropylene-graft-maleic anhydride, and either hexadecyltrimethoxysilane or 1H,1H,2H,2H-perfluorooctyltriethoxysilane is presented. The resulting epoxy coatings based on hydrophobic HMPs were cast on aeronautical carbon fiber-reinforced panels to improve their anti-icing performance. Wettability and anti-icing behavior of the prepared composites were investigated at 25 °C and -30 °C (complete icing time), respectively. Samples cast with the composite coating can achieve up to 30 °C higher water contact angle and doubled icing time than aeronautical panels treated with unfilled epoxy resin. A low content (2 wt %) of tailored HMPs causes an increase of ∼26% in the glass transition temperature of the coatings compared to pristine resin, confirming the good interaction between the hemp filler and epoxy matrix at the interphase. Finally, atomic force microscopy reveals that the HMPs can induce the formation of a hierarchical structure on the surface of casted panels. This rough morphology, combined with the silane activity, allows the preparation of aeronautical substrates with enhanced hydrophobicity, anti-icing capability, and thermal stability.

Effect of the Coupling Agent (3-Aminopropyl) Triethoxysilane on the Structure and Fire Behavior of Solvent-Free One-Pot Synthesized Silica-Epoxy Nanocomposites

Uniformly distributed silica/epoxy nanocomposites (2 and 6 wt.% silica content) were obtained through a “solvent-free one-pot” process. The inorganic phases were obtained through “in situ” sol-gel chemistry from two precursors, tetraethyl orthosilicate (TEOS) and (3-aminopropyl)-triethoxysilane (APTES). APTES acts as a coupling agent. Surprisingly when changing TEOS/APTES molar ratio (from 2.32 to 1.25), two opposite trends of glass transformation temperature (Tg) were observed for silica loading, i.e., at lower content, a decreased Tg (for 2 wt.% silica) and at higher content an increased Tg (for 6 wt.% silica) was observed. High-Resolution Transmission Electron Microscopy (HRTEM) showed the formation of multi-sheet silica-based nanoparticles with decreasing size at a lower TEOS/APTES molar ratio. Based on a recently proposed mechanism, the experimental results can be explained by the formation of a co-continuous hybrid network due to reorganization of the epoxy matrix around two different “in situ” sol-gel derived silicatic phases, i.e., micelles formed mainly by APTES and multi-sheet silica nanoparticles. Moreover, the concentration of APTES affected the size distribution of the multi-sheet silica-based nanoparticles, leading to the formation of structures that became smaller at a higher content. Flammability and forced-combustion tests proved that the nanocomposites exhibited excellent fire retardancy.

Solvent-Free One-Pot Synthesis of Epoxy Nanocomposites Containing Mg(OH)2 Nanocrystal-Nanoparticle Formation Mechanism

Epoxy nanocomposites containing Mg(OH)₂ nanocrystals (MgNCs, 5.3 wt %) were produced via an eco-friendly "solvent-free one-pot" process. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and thermogravimetric analysis (TGA) confirm the presence of well-dispersed MgNCs. HRTEM reveals the presence also of multisheet-silica-based nanoparticles and a tendency of MgNCs to intergrow, leading to complex nanometric structures with an intersheet size of ∼0.43 nm, which is in agreement with the lattice spacing of the Mg(OH)₂ (001) planes. The synthesis of MgNCs was designed on the basis of a mechanism initially proposed for the preparation of multisheet-silica-based/epoxy nanocomposites. The successful "in situ" generation of MgNCs in the epoxy via a "solvent-free one-pot" process confirms the validity of the earlier disclosed mechanism and thus opens up possibilities of new NCs with different fillers and polymer matrix. The condition would be the availability of a nanoparticle precursor soluble in the hydrophobic resin, giving the desired phase through hydrolysis and polycondensation.

Structure and Bottom-up Formation Mechanism of Multisheet Silica-Based Nanoparticles Formed in an Epoxy Matrix through an In Situ Process

Organic/inorganic hybrid composite materials with the dispersed phases in sizes down to a few tens of nanometers raised very great interest. In this paper, it is shown that silica/epoxy nanocomposites with a silica content of 6 wt % may be obtained with an "in situ" sol-gel procedure starting from two precursors: tetraethyl orthosilicate (TEOS) and 3-aminopropyl-triethoxysilane (APTES). APTES also played the role of a coupling agent. The use of advanced techniques (bright-field high-resolution transmission electron microscopy, HRTEM, and combined small- and wide-angle X-ray scattering (SAXS/WAXS) performed by means of a multirange device Ganesha 300 XL+) allowed us to evidence a multisheet structure of the nanoparticles instead of the gel one typically obtained through a sol-gel route. A mechanism combining in a new manner well-assessed knowledge regarding sol-gel chemistry, emulsion formation, and Ostwald ripening allowed us to give an explanation for the formation of the observed lamellar nanoparticles.

Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride

Thermosetting polymers have been widely used in many industrial applications as adhesives, coatings and laminated materials, among others. Recently, bisphenol A (BPA) has been banned as raw material for polymeric products, due to its harmful impact on human health. On the other hand, the use of aromatic amines as curing agents confers excellent thermal, mechanical and flame retardant properties to the final product, although they are toxic and subject to governmental restrictions. In this context, sugar-derived diepoxy monomers and anhydrides represent a sustainable greener alternative to BPA and aromatic amines. Herein, we report an "in-situ" sol-gel synthesis, using as precursors tetraethylorthosilicate (TEOS) and aminopropyl triethoxysilane (APTS) to obtain bio-based epoxy/silica composites; in a first step, the APTS was left to react with 2,5-bis[(oxyran-2-ylmethoxy)methyl]furan (BOMF) or diglycidyl ether of bisphenol A (DGEBA)monomers, and silica particles were generated in the epoxy in a second step; both systems were cured with methyl nadic anhydride (MNA). Morphological investigation of the composites through transmission electron microscopy (TEM) demonstrated that the hybrid strategy allows a very fine distribution of silica nanoparticles (at nanometric level) to be achieved within a hybrid network structure for both the diepoxy monomers. Concerning the fire behavior, as assessed in vertical flame spread tests, the use of anhydride curing agent prevented melt dripping phenomena and provided high char-forming character to the bio-based epoxy systems and their phenyl analog. In addition, forced combustion tests showed that the use of anhydride hardener instead of aliphatic polyamine results in a remarkable decrease of heat release rate. An overall decrease of the smoke parameters, which is highly desirable in a context of greater fire safety was observed in the case of BOMF/MNA system. The experimental results suggest that the effect of silica nanoparticles on fire behavior appears to be related to their dispersion degree.

A New Strategy to Produce Hemp Fibers through a Waterglass-Based Ecofriendly Process

Natural fibers such as kenaf, hemp, flax, jute, and sisal have become the subject of much research as potential green or eco-friendly reinforcement composites, since they assure the reduction of weight, cost, and CO2 release with less reliance on oil sources. Herein, an inexpensive and eco-friendly waterglass treatment is proposed, allowing the production of silica-coated fibers that can be easily obtained in micro/nano fibrils through a low power mixer. The silica coating has been exploited to improve the chemical compatibility between fibers and the polymer matrix through the reaction of silanol groups with suitable coupling agents. In particular, silica-coated fibers easily functionalized with (3-Aminopropyl) triethoxysilane (APTS) were used as a filler in the manufacturing of epoxy-based composites. Morphological investigation of the composites through Scanning Electron Microscopy (SEM) demonstrated that the filler has a tendency to produce a web-like structure, formed by continuously interconnected fibrils and microfibrils, from which particularly effective mechanical properties may be obtained. Dynamic Mechanical Analysis (DMA) shows that the functionalized fibers, in a concentration of 5 wt%, strongly affect the glass transformation temperature (10 °C increase) and the storage modulus of the pristine resin. Taking into account the large number of organosilicon compounds (in particular the alkoxide ones) available on the market, the new process appears to pave the way for the cleaner and cheaper production of biocomposites with different polymeric matrices and well-tailored interfaces.

Non Monotonous Effects of Noncovalently Functionalized Graphene Addition on the Structure and Sound Absorption Properties of Polyvinylpyrrolidone (1300 kDa) Electrospun Mats

Graphene is an attractive component for high-performance stimuli-responsive or 'smart' materials, shape memory materials, photomechanical actuators, piezoelectric materials and flexible strain sensors. Nanocomposite fibres were produced by electrospinning high molecular weight Polyvinylpyrrolidone (PVP-1300 kDa) in the presence of noncovalently functionalised graphene obtained through tip sonication of graphite alcoholic suspensions in the presence of PVP (10 kDa). Bending instability of electrospun jet appears to progressively increase at low graphene concentrations with the result of greater fibre stretching that leads to lower fibre diameter and possibly conformational changes of PVP. Further increase of graphene content seams having the opposite effect leading to greater fibre diameter and Raman spectra similar to the pure PVP electrospun mats. All this has been interpreted on the basis of currently accepted model for bending instability of electrospun jets. The graphene addition does not lower the very high sound absorption coefficient, α, close to unity, of the electrospun PVP mats in the frequency range 200⁻800 Hz. The graphene addition affects, in a non-monotonous manner, the bell shaped curves of α versus frequency curves becoming sharper and moving to higher frequency at the lower graphene addition. The opposite is observed when the graphene content is further increased.

Maternal attachment style and depression associated with childbirth: preliminary results from a European and US cross-cultural study

Background

Insecure attachment style relates to major depression in women, but its relationship to depression associated with childbirth is largely unknown. A new UK-designed measure, the Attachment Style Interview (ASI), has potential for cross-cultural use as a risk marker for maternal disorder.

Aims

To establish the reliability of the ASI across centres, its stability over a 9-month period, and its associations with social context and majoror minor depression.

Method

The ASI was used by nine centres antenatally on 204 women, with 174 followed up 6 months postnatally. Interrater reliability was tested and the ASI was repeated on a subset of 96 women. Affective disorder was assessed by means of the Structured Clinical Interview for DSM–IV.

Results

Satisfactory interrater reliability was achieved with relatively high stability rates at follow-up. Insecure attachment related to lower social class position and more negative social context. Specific associations of avoidant attachment style (angry–dismissive or withdrawn) with antenatal disorder, and anxious style (enmeshed or fearful) with postnatal disorder were found.

Conclusions

The ASI can be used reliably in European and US centres as a measure for risk associated with childbirth. Its use will contribute to theoretically underpinned preventive action for disorders associated with childbirth.

Silica Treatments: A Fire Retardant Strategy for Hemp Fabric/Epoxy Composites

In this paper, for the first time, inexpensive waterglass solutions are exploited as a new, simple and ecofriendly chemical approach for promoting the formation of a silica-based coating on hemp fabrics, able to act as a thermal shield and to protect the latter from heat sources. Fourier Transform Infrared (FTIR) and solid-state Nuclear Magnetic Resonance (NMR) analysis confirm the formation of ⁻C⁻O⁻Si⁻ covalent bonds between the coating and the cellulosic substrate. The proposed waterglass treatment, which is resistant to washing, seems to be very effective for improving the fire behavior of hemp fabric/epoxy composites, also in combination with ammonium polyphosphate. In particular, the exploitation of hemp surface treatment and Ammonium Polyphosphate (APP) addition to epoxy favors a remarkable decrease of the Heat Release Rate (HRR), Total Heat Release (THR), Total Smoke Release (TSR) and Specific Extinction Area (SEA) (respectively by 83%, 35%, 45% and 44%) as compared to untreated hemp/epoxy composites, favoring the formation of a very stable char, as also assessed by Thermogravimetric Analysis (TGA). Because of the low interfacial adhesion between the fabrics and the epoxy matrix, the obtained composites show low strength and stiffness; however, the energy absorbed by the material is higher when using treated hemp. The presence of APP in the epoxy matrix does not affect the mechanical behavior of the composites.

Caribbean nurses migrating to the UK: a gender-focused literature review

BACKGROUND

International nurse recruitment is an integral part of government health care strategy in many countries. However, the gendered implications of nurse migration have been little explored despite the fact that the nursing workforce is predominantly made up of women.

AIM

Based on the migration of nurses from the English-speaking Caribbean region to the UK, this paper explores the significance of gender at both the macro and micro levels.

METHODS

Four strands of inquiry were explored: nurse migration, impact on development, work experiences and family life. Key terms were used to search the electronic databases SSCI, EBSCO and JSTOR. An interpretative framework based on the feminist theory of intersectionality was used to systematically review the 15 studies that met the inclusion criteria.

FINDINGS

Gender issues are significant across all aspects of the migratory process. Migrant nurses contribute to social progress through remittances and knowledge gained abroad although overall, nurse migration negatively impacts development and there are hidden implications for women. For some Caribbean nurses, migration reflects increased economic freedom; however, for others, gender inequality lies at the centre of the decision to relocate. Gender inequality also permeates the lives of many migrant nurses even in countries where economic and work conditions are improved.

CONCLUSIONS

The ramifications of nurse migration cannot be fully understood without attention to gender inequalities and the specific socio-economic contexts in which they exist. There is need for a gender-centred approach to international nursing recruitment policy that takes account not only of the impact on developing countries, but also of the well-being of migrant nurses themselves.

The childhood experience of care and abuse questionnaire (CECA.Q): validation in a community series

BACKGROUND

Childhood neglect and abuse, as measured by retrospective interview, is highly predictive of psychiatric disorder in adult life and has an important role in aetiological models. However, such measures are labour-intensive, costly, and thus restricted to relatively modest sample sizes. A compact self-report assessment of childhood experience is invaluable for research screening purposes and large-scale survey investigation.

METHOD

A self-report questionnaire (CECA.Q) was developed to mirror an existing validated interview measure: the childhood experience of care and abuse (CECA). The questionnaire assessed lack of parental care (neglect and antipathy), parental physical abuse, and sexual abuse from any adult before age 17. A high-risk series of 179 London women were interviewed using the CECA together with the PSE psychiatric assessment, and completed the CECA.Q at later follow-up. Repeat CECA.Qs were returned for 111 women and 99 women additionally completed the parental bonding instrument (PBI; Parker, Tupling, & Brown, 1979).

RESULTS

Satisfactory internal scale consistency was achieved on the CECA.Q for antipathy (alpha = .81) and neglect (alpha = .80) scales. There was satisfactory test-retest for both care and abuse scales. Significant associations were found between CECA.Q scales and the parallel interview scales with cut-offs determined for high sensitivity and specificity. CECA.Q neglect and antipathy scales were also significantly related to PBI parental care. CECA.Q scales were significantly related to lifetime history of depression. Optimal cut-off scores revealed significant odds ratios (average of 2) for individual scales and depression. When indices were compiled to reflect peak severity of each type of adversity across perpetrator, odds-ratios increased (average 3). A dose-response effect was evident with the number of types of neglect/abuse and rate of lifetime depression.

CONCLUSION

The CECA.Q shows satisfactory reliability and validity as a self-report measure for adverse childhood experience. The merits of having parallel questionnaire and interview instruments for both research and clinical work are discussed.

Contextual Assessment of the Maternity Experience: development of an instrument for cross-cultural research

BACKGROUND

There is evidence that stressors may trigger the onset of a depressive episode in vulnerable women. A new UK interview measure, the Contextual Assessment of the Maternity Experience (CAME), was designed to assess major risk factors for emotional disturbances, especially depression, during pregnancy and post-partum.

AIMS

With in the context of a cross-cultural study, to establish the usefulness of the CAME, and to test expected associations of the measure with characteristics of the social context and with major or minor depression.

METHOD

The CAME was administered antenatally and postnatally in ten study sites, respectively to 296 and 249 women. Affective disorder throughout pregnancy and up to 6 months postnatally was assessed by means of the Structured Clinical Interview for DSM-IVAxis I Disorders.

RESULTS

Adversity, poor relationship with either a partner or a confidant, and negative feelings about the pregnancy all predicted onset of depression during the perinatal period.

CONCLUSIONS

The CAME was able to assess major domains relevant to the psychosocial context of the maternity experience in different cultures. Overall, the instrument showed acceptable psychometric properties in its first use in different cultural settings.

The Vulnerable Attachment Style Questionnaire (VASQ): an interview-based measure of attachment styles that predict depressive disorder

BACKGROUND

The Vulnerable Attachment Style Questionnaire (VASQ) was developed to provide a brief self-report tool to assess adult attachment style in relation to depression and validated against an existing investigator-based interview (Attachment Style Interview--ASI). This paper describes the development and scoring of the VASQ and its relationship to poor support and major depression.

METHOD

Items for the VASQ reflected behaviours, emotions and attitudes relating to attachment relationship style, drawn directly from the ASI. The VASQ was validated against the ASI for 262 community-based subjects. Test-retest was determined on 38 subjects.

RESULTS

Factor analysis derived two factors, labelled 'insecurity' and 'proximity-seeking'. The VASQ insecurity dimension had highest mean scores for those with interview-based Angry-dismissive and Fearful styles and was significantly correlated with degree of interview-based insecurity. The proximity-seeking VASQ scores had highest mean for those with Enmeshed interview attachment style and was uncorrelated with ASI insecurity. VASQ scores were highly correlated with a well-known self-report measure of insecure attachment (Relationship Questionnaire) and text-retest reliability of the VASQ was satisfactory. The total VASQ score and the insecurity subscale proved highly related to poor support and to depressive disorder. This was not the case for the proximity-seeking subscale.

CONCLUSION

The VASQ is a brief self-report measure that distinguishes individuals with attachment styles vulnerable for depressive disorder. The use of the measure for screening in research and clinical contexts is discussed.

Childhood Experience of Care and Abuse Questionnaire (CECA.Q). Validation of a screening instrument for childhood adversity in clinical populations

BACKGROUND

Interview measures for investigating adverse childhood experiences, such as the Childhood Experience of Care and Abuse (CECA) instrument, are comprehensive and can be lengthy and time-consuming. A questionnaire version of the CECA (CECA.Q) has been developed which could allow for screening of individuals in research settings. This would enable researchers to identify individuals with adverse early experiences who might benefit from an in-depth interview. This paper aims to validate the CECA.Q against the CECA interview in a clinical population.

METHODS

One hundred and eight patients attending an affective disorders service were assessed using both the CECA interview and questionnaire measures. A follow-up sample was recruited 3 years later and sent the questionnaire. The questionnaire was also compared with the established Parental Bonding Instrument (PBI).

RESULTS

Agreement between ratings on the interview and questionnaire were high. Scales measuring antipathy and neglect also correlated highly with the PBI. The follow-up sample revealed the questionnaire to have a high degree of reliability over a long period of time.

CONCLUSIONS

The CECA.Q appears to be a reliable and valid measure which can be used in research on clinical populations to screen for individuals who have experienced severe adversity in childhood.

Childhood adversity, parental vulnerability and disorder: examining inter-generational transmission of risk

BACKGROUND

An investigation of intergenerational factors associated with psychiatric disorder in late adolescence/early adulthood was undertaken to differentiate influences from maternal disorder, maternal poor psychosocial functioning and poor parenting, on offspring.

METHOD

The sample comprised an intensively studied series of 276 mother-offspring pairs in a relatively deprived inner-city London area with high rates of lone parenthood and socio-economic disadvantage. The paired sample was collected over two time periods: first a consecutively screened series of mothers and offspring in 1985-90 (n = 172 pairs) and second a 'vulnerable' series of mothers and offspring in 1995-99 (n = 104 pairs). The vulnerable mothers were selected for poor interpersonal functioning and/or low self-esteem and the consecutive series were used for comparison. Rates of childhood adversity and disorder in the offspring were examined in the two groups. Maternal characteristics including psychosocial vulnerability and depression were then examined in relation to risk transmission.

RESULTS

Offspring of vulnerable mothers had a fourfold higher rate of yearly disorder than those in the comparison series (43% vs. 11%, p < .001). They were twice as likely as those in the comparison series to have experienced childhood adversity comprising either severe neglect, physical or sexual abuse before age 17. Physical abuse, in particular, perpetrated either by mother or father/surrogate father was significantly raised in the vulnerable group. Analysis of the combined series showed that maternal vulnerability and neglect/abuse of offspring provided the best model for offspring disorder. Maternal history of depression had no direct effect on offspring disorder; its effects were entirely mediated by offspring neglect/abuse. Maternal childhood adversity also had no direct effect.

CONCLUSIONS

Results are discussed in relation to psychosocial models of risk transmission for disorder. Maternal poor psychosocial functioning needs to be identified as a factor requiring intervention in order to stem escalation of risk across generations.

Adult attachment style. II: Its relationship to psychosocial depressive-vulnerability

BACKGROUND

A range of studies show adult attachment style is associated with depressive-vulnerability factors such as low self-esteem, poor support and childhood adversity. However, there is wide inconsistency shown in the type of insecure style most highly associated. Few studies have examined attachment style in relation to clinical depression together with a range of such factors in epidemiological series. The present study uses an interview measure of adult attachment which differentiates type of attachment style and degree of insecurity of attachment, to see: (a) if it adds to other vulnerability in predicting depression and (b) if there is specificity of style to type of vulnerability.

METHOD

Two hundred and twenty-two high-risk and 80 comparison women were selected from questionnaire screenings of London GP patient lists and intensively interviewed. The Attachment Style Interview (ASI) differentiated five styles (Enmeshed, Fearful, Angry-dismissive, Withdrawn and Standard) as well as the degree to which attitudes and behaviour within such styles were dysfunctional ('non-standard'). Attachment style was examined in relation to low self-esteem, support and childhood experience of neglect or abuse, and all of these examined in relation to clinical depression in a 12-month period.

RESULTS

The presence of any 'non-standard' style was significantly related to poor support, low self-esteem and childhood adversity. Some specificity of type of style and type of vulnerability was observed. Logistic regression showed that non-standard Enmeshed, Fearful and Angry-dismissive styles, poor support and childhood neglect/abuse provided the best model for clinical depression.

CONCLUSION

Non-standard attachment in the form of markedly Enmeshed, Fearful or Angry-dismissive styles was shown to be associated with other depressive-vulnerability factors involving close relationships, self-esteem and childhood adversity and added to these in modelling depression.

Adult attachment style. I: Its relationship to clinical depression

BACKGROUND

Although there are an increasing number of studies showing an association of adult attachment style to depressive disorder, such studies have rarely utilised epidemiological approaches with large community-based series and have relied heavily on brief self-report measurement of both attachment style and symptoms. The result is a wide inconsistency in the type of insecure style shown to relate to disorder. The present study examined adult attachment style in a high-risk community sample of women in relation to clinical depression. It utilised an interview measure of adult attachment which allowed for an assessment of both type of attachment style and the degree of insecurity of attachment. A companion paper examines its relationship with other depressive-vulnerability (Bifulco et al. 2002).

METHOD

Two hundred and twenty-two high-risk and 80 comparison women were selected from questionnaire screenings of London GP patient lists and intensively interviewed. A global scale of attachment style based on supportive relationships (with partner and very close others) together with attitudes to support-seeking, derived the four styles paralleling those from self-report attachment assessments (Secure, Enmeshed, Fearful, Avoidant). In order to additionally reflect hostility in the scheme, the Avoidant category was subdivided into 'Angry-dismissive' and 'Withdrawn'. The degree to which attitudes and behaviour within such styles were dysfunctional ('non-standard') was also assessed. Attachment style was examined in relation to clinical depression in a 12-month period. For a third of the series this was examined prospectively to new onset of disorder.

RESULTS

The presence of any insecure style was significantly related to 12-month depression. However, when controls were made for depressive symptomatology at interview, only the 'non-standard' levels of Enmeshed, Fearful or Angry-dismissive styles related to disorder. Withdrawn-avoidance was not significantly related to disorder.

CONCLUSION

The relationship of attachment style to clinical depression is increased by differentiating the degree of insecurity of style and differentiating hostile and non-hostile avoidance.

Predicting onset of depression: the Vulnerability to Depression Questionnaire

OBJECTIVES

The development of a self-report questionnaire capable of assessing cognitive and interpersonal vulnerability factors for clinical depression is described. The Vulnerability to Depression Questionnaire (VDQ) was developed to provide a brief, economical alternative to the Self-Evaluation and Social Support interview (SESS; O'Connor & Brown, 1984), assessing negative evaluation of self, negative interaction with partner or child and lack of a support figure.

DESIGN

The VDQ was tested in a prospective study of community-based women who were contacted on three occasions over the course of approximately 1 year, to: (i) compare the VDQ's capacity to categorize vulnerability compared with the SESS interview, and (ii) to test the VDQ's prediction of onset of clinical depression during the follow-up.

METHOD

Selected nondepressed respondents completed the VDQ and were interviewed to determine their vulnerability using the SESS. They were re-interviewed on two further occasions during the follow-up period, and the VDQ was also re-administered at the time of first follow-up. Onset of clinical depression during the follow-up was assessed by interview at each contact.

RESULTS

Comparison of VDQ and SESS interview classification of participants' vulnerability at first contact indicated that the questionnaire had good sensitivity and specificity. Test-retest scores for the VDQ indicated satisfactory levels of reliability. VDQ scores also predicted onset of clinical depression in the follow-up period.

CONCLUSIONS

Results suggest that the VDQ is an economical and effective means of screening large populations for the purposes of risk assessment, to aid future research into clinical depression and to facilitate the implementation of intervention strategies.

Lifetime stressors and recurrent depression: preliminary findings of the Adult Life Phase Interview (ALPHI)

BACKGROUND

The well-established association between stress and depression is explored in a lifespan context in relation to adverse childhood experience. A new retrospective interview instrument, the Adult Life Phase Interview (ALPHI) examined the number of chronic stressors (or 'adversities') experienced over the adult life course in relation to chronic or recurrent clinical depression. The role of such lifetime adversity in mediating the relationship between childhood neglect/ abuse and adult disorder was examined.

METHOD

The ALPHI uses an investigator-based, contextual approach suited to retrospective and time-linked enquiries. Reliability of the instrument was found to be satisfactory. Its association with both lifetime clinical depression and childhood neglect or abuse was examined in a community series of 198 women, consisting of 99 sister pairs, where one-half of the series was selected for having had adverse childhood experience and the other for comparison.

RESULTS

Adult adversity, both at settled/fixed times and at times of major life change, was significantly higher among those with prior childhood neglect or abuse. Both a high adult adversity score and childhood neglect or abuse were related to chronic or recurrent episodes of clinical depression, with logistic regression indicating both indices contributed independently to disorder. The same results held when controls were made for sister status, given possible familial bias in experience, and for age, since women under age 25 had fewer adult phases and less adversity.

CONCLUSIONS

Characteristics of adult life phases and change-points are described and the relevance of the measure for intensive survey work seeking to investigate relationships between lifespan experience and depression is discussed.

Predicting depression in women: the role of past and present vulnerability

BACKGROUND

A prospective study, covering just over a 1-year period, sought to confirm an earlier finding that around 40% of women who experience a severe life event in the presence of two ongoing psychosocial vulnerability factors, (negative close relationships and low self-esteem) will develop a major depressive episode. Distal risk factors were examined to see if they improved prediction.

METHODS

A population sample of 105 mainly working-class mothers with vulnerability and without depression were interviewed three times over a 14-month period to date the occurrence of severe life events and onset of major depression. Degree of vulnerability was assessed at first contact together with distal risk in terms of childhood neglect/abuse and any earlier episodes of depression.

RESULTS

Thirty-seven per cent of these vulnerable women became depressed in the study period. The majority experienced a severe life event, and of these, 48% had onsets. Contrary to expectation, risk was only a little less among those with just one of the two vulnerability factors. Two-thirds of women with an onset had been depressed in previous years. Although this was associated with increased risk, the effect was greatest for those who had experienced an episode before age 20. A relationship between childhood neglect/abuse and onset was entirely accounted for by such early depression.

CONCLUSION

An aetiological model of depression outlined in earlier research was confined with a new factor of teenage depression shown to increase risk of onset.

Memories of childhood neglect and abuse: corroboration in a series of sisters

Reports from 87 community-based sister-pairs, selected for high rates of neglect or abuse in childhood, have been used to establish validity of the CECA, a retrospective interview measure of childhood experience. Corroboration was based on independent assessments of sisters' accounts of what happened to each other in childhood. Corroboration of scales assessing parental neglect, physical abuse in the household and sexual abuse (either household or nonhousehold) was satisfactory, with a mean correlation for the three experiences of .60 (weighted kappa [Kw]). Concordance reflected the degree to which experience was shared and was judged by comparing the sisters' accounts of their own experience. Among sisters with shared (concordant) experience for neglect or abuse, corroboration was high (mean of .74), but for those with nonshared (nonconcordant) experience it was largely absent (mean of .01). The degree to which the experiences of neglect or abuse were concordant was related to whether the perpetrator was a member of the household. Neglect and physical abuse were by definition from household members (mainly parents) and involved high concordance of experience. Sexual abuse occurred from many sources and in practice was commonly from an adult living outside the household and such experiences were less likely to be shared by sisters. An overall index indicating the presence of at least one abusive experience before the age of 17 showed a concordance of .64 with corroboration between sisters as high as .70. Issues involving retrospective recall and measurement are discussed.

Cognitive coping response to crises and onset of depression

This paper consider the relationship between cognitive coping responses to severe life events and related difficulties and the risk of onset of case depression in a sample of 150 mothers living in Islington, North London. A period between a first interview and a followup interview 12 months later was covered, and any onset in the follow-up period examined. Three types of 'negative' cognitive response to a severe life event/difficulty complex were related to an increased risk of depression. These were inferred denial, self-blame and pessimism. One 'positive' cognitive factor, that of downplaying, was inversely related to onset. A negative cognitive response to crises was found to be associated with the most serious of the events, defined by their match with an ongoing marked difficulty. However, both matching severe events and a negative cognitive response were required to model onset of depression. Negative cognitive coping responses were also related to type of event: all were related to crises involving partners. In addition, self-blame was associated with crises involving children's behaviour, and there was some evidence that denial was related to pregnancy/birth crises, and pessimism, to health/death crises. A negative cognitive response was also associated with other risk factors such as prior vulnerability and failure to receive support in the crisis. However, when these were taken into account a negative response to a crisis was still required in modelling onset of depression. Issues of possible bias are addressed.

Childhood Experience of Care and Abuse (CECA): a retrospective interview measure

The development of a retrospective, investigator-based interview measure of Childhood Experience of Care and Abuse (CECA) used with two community samples of adults in London is described. The component ratings are shown to have satisfactory inter-rater reliability and also validity as determined by agreement between sisters' independent accounts. The association between the different childhood scales is explored as well as the relationship of childhood experiences to adult depression. Methodological issues concerning investigator-based versus respondent-based measures of childhood are discussed and a case made for use of the former. Advantages of using the CECA, a retrospective, time-based measure of childhood, are outlined.

Childhood Experience of Care and Abuse (CECA): a retrospective interview measure

The development of a retrospective, investigator-based interview measure of Childhood Experience of Care and Abuse (CECA) used with two community samples of adults in London is described. The component ratings are shown to have satisfactory inter-rater reliability and also validity as determined by agreement between sisters' independent accounts. The association between the different childhood scales is explored as well as the relationship of childhood experiences to adult depression. Methodological issues concerning investigator-based versus respondent-based measures of childhood are discussed and a case made for use of the former. Advantages of using the CECA, a retrospective, time-based measure of childhood, are outlined.

Social factors and recovery from anxiety and depressive disorders. A test of specificity

Analysis of 33 instances of recovery or improvement among 92 women with anxiety, and 49 instances of recovery and improvement among 67 episodes of depression, showed that recovery and improvement, when compared with conditions not changing, were associated with a prior positive event. Such events were characterised by one or more of three dimensions: the 'anchoring' dimension involved increased security; 'fresh-start', increased hope arising from a lessening of a difficulty or deprivation; and 'relief', the amelioration of a difficulty not involving any sense of a fresh start. Events characterised by anchoring were more often associated with recovery or improvement in anxiety, and those characterised as fresh-start were associated with recovery or improvement in depression. Recovery or improvement in both disorders was more likely to be associated with both anchoring and fresh-start events. The study involved the reworking of some social and clinical material, and although done blind should be seen as exploratory.

Early sexual abuse and clinical depression in adult life

Sexual abuse in childhood and adolescence was studied in 286 working-class mothers living in Islington, who were contacted on three occasions over a two-year period. The sample was collected primarily to study current vulnerability factors in the onset of depression, but childhood measures were also included to look at longer-term risk factors. Twenty-five women - 9% of the sample - reported sexual abuse involving physical contact before age 17 and, of these, 64% had case depression in a three-year period (which included the year before first interview). While such abuse was related to other earlier stressful experiences such as parental indifference, violence to the child and institutional stay, it was associated with an increased risk of depression over and above these factors. Sexual abuse before age 17 also related to having been divorced/separated or never having married/cohabited.

Self-esteem and depression. IV. Effect on course and recovery

The present paper, the fourth and last in a series examining the role of self-esteem in depressive disorder in the general population, deals with recovery/improvement from a disorder at a case level. Both positive evaluation of self (PES) and absence of negative evaluation of self (NES) measured during a chronic episode are related to subsequent recovery or improvement. A causal effect is suggested since the measure adds over and above to that of environmental factors previously established to relate to recovery/improvement--the reduction of an ongoing difficulty or fresh-start event. Positive evaluation of self was also related to recovery/improvement from subsequent onsets of case depression. In this instance, unlike that for the chronic conditions, self-esteem was measured outside the episode of depression. A causal effect was also suggested because it made an independent contribution vis-a-vis the effect of fresh-start events. Given the small size of the sample the study should be seen as an exploratory one.

Self-esteem and depression. III. Aetiological issues

This is the last of a series of three papers dealing with the role of self-esteem in the onset of clinical depression. On the basis of a longitudinal population enquiry a comprehensive psychosocial model of depression is developed. It is concluded that self-esteem (primarily in terms of a negative measure) does play a significant role. However, this can be only properly interpreted in the light of the full model. This highlights: 1. the importance of the occurrence of both a negative environmental factor (negative interaction with children or husband for married or negative interaction with children or lack of a very close tie for single mothers) and a negative psychological factor (low self-esteem or chronic subclinical condition); and 2. how a relatively small group of high risk women in these terms (23% of total at risk based on measures collected well before any onset) contain three-quarters of all instances of onset of depression occurring over a 12 month period.

Self-esteem and depression. II. Social correlates of self-esteem

The Self-Evaluation and Social Support Schedule (SESS), an interview-based instrument, is described, which aims to give a comprehensive description of a person's social milieu in terms of 'objective' and 'subjective' measures. On the basis of a population survey of 400 largely working-class women, a tentative causal model is developed which relates both the quality of current interpersonal ties and childhood experiences to current negative and positive measures of self-esteem. A major purpose of the exercise is to develop positive and negative indices of the social environment that can be used to elucidate the aetiological role of self-esteem in the development of depression. This is the task of a third paper.

Self-esteem and depression. 1. Measurement issues and prediction of onset

Research on the efficacy of measures of self-esteem to predict onset of depression has produced highly variable results. Longitudinal population studies in London and Edinburgh have produced positive findings, but there are a number of studies with negative results. This paper examines in more detail than hitherto the results of the London, Islington, longitudinal study and discusses issues of measurement which might explain the variable success of such predictions.

Motherhood, employment and the development of depression. A replication of a finding?

A prospective inquiry of a largely working-class sample of women with children considers the effect of employment on risk of developing clinical depression. The hypothesis was that there would be a direct protective effect arising from employment once quality of other support was taken into account. In fact full-time working mothers were at high risk. This appeared to be explained by either prior work strain or a severe event involving 'deviant' behaviour on the part of husband/boyfriend or child. Neither factor was relevant for part-time workers. The severe events appeared to be particularly depressogenic for full-time workers because they represented either failure in the motherhood role or a sense of entrapment in an unrewarding work/domestic situation. However, those in part-time work had a low rate of onset compared with non-workers, and the difference appears to be related to non-working women feeling less secure about their marriages.

Life events, difficulties and recovery from chronic depression

Reductions in an overall score of ongoing difficulties and the occurrence of a 'fresh start' event often preceded the recovery or improvement of women in a general-population survey suffering from chronic depression, i.e. with episodes lasting 12 months or more. In addition, overall levels of difficulties and presence of social support were independently related to recovery or improvement. Some of the life-changes preceding recovery were threatening, but all promised some hope of a better future. Evidence is presented that the results as a whole are unlikely to be due to incipient changes in clinical condition leading the women to make changes in their environment, but some bias of this kind cannot be entirely ruled out.

Loss of parent in childhood and adult psychiatric disorder: the role of social class position and premarital pregnancy

This paper addresses the critique which maintains that loss of parent in a sample of female adults plays no role in determining current depression over and above that of low social class position with which such loss is associated. It examines a series of variables which combine to determine current social class position and which seem to stem from lack of adequate replacement care following loss of mother. The experience of a premarital pregnancy and the way in which women cope with it emerge as critical in this process. The relationship of low social class to the onset of depression is discussed in the light of better-known vulnerability factors such as low confiding in, and undependability of, marital partner, employment outside the home and number of children. It is concluded that a current low social class position, far from explaining away the association between loss of mother and current depression, may itself be brought about by a chain of circumstances stemming from the loss. Once again, the quality of replacement care is shown to play a critical role.

Life events, vulnerability and onset of depression: some refinements

A prospective study of 400 largely working-class women with children living at home has once again demonstrated the major importance of long-term severe threatening life events in provoking caseness of depression. However, it again shows that only about one out of five women experiencing such an event go on to develop depression at a case level. This paper demonstrates that more sensitive characterisation of severe events can greatly increase the size of this association. This is done both by improving the description of the event itself and by taking into account various ways in which the event can 'match' characteristics of the women present at the first interview, well before the occurrence of the event or any onset of depression.

Loss of parent in childhood and adult psychiatric disorder: the role of lack of adequate parental care

The inconclusiveness of the literature on the role of loss of parent in influencing psychiatric disorder in adulthood is well known. A number of reasons involving sampling, location and other methodological features, are given to account for these contradictory findings. A study specially designed to cope with these features is then described and basic results are reported. These indicate that, in a sample of women aged 18-65, loss of mother before the age of 17, either by death or by separation of one year or more, was associated with clinical depression in the year of interview. Loss of father by death was in no way associated with current depression, but separation from father showed a trend which, however, did not reach statistical significance. Control for other possible confounding factors did not change this patterning of results; these were further supported when psychiatric episodes earlier in adulthood were examined. Examination of the caregiving arrangements in childhood suggests that it is 'lack of care', defined in terms of neglect rather than simply hostile parental behaviour, which accounts for the raised rate of depression. Such 'lack of care' is more frequent after loss of mother than after loss of father.

Life stress, chronic subclinical symptoms and vulnerability to clinical depression

Prospective enquiries of the role of social factors in the aetiology of depression are faced with the problem of who to exclude from the enquiry in terms of psychiatric symptomatology present at first contact. With this problem in mind the role of subclinical symptoms among women not cases of depression has been examined in terms of their relation with a subsequent onset of caseness depression. Psychosocial factors of particular importance in the development of such depression were low self-esteem, marked long-term difficulties and severe life events arising out of (or 'matching') these difficulties. These psychosocial factors were also correlated with the presence of subclinical symptoms. It is concluded that although subclinical symptoms relate to a raised risk of subsequent depression at a caseness level there is no evidence that there is inherent vulnerability stemming from such subclinical symptoms over and above that explained by the psychosocial correlates.