Structure-Property Relationships for the Electronic Applications of Bis-Adduct Isomers of Phenyl-C61 Butyric Acid Methyl Ester

Higher adducts of a fullerene, such as the bis-adduct of PCBM (bis-PCBM), can be used to achieve shallower molecular orbital energy levels than, for example, PCBM or C60. Substituting the bis-adduct for the parent fullerene is useful to increase the open-circuit voltage of organic solar cells or achieve better energy alignment as electron transport layers in, for example, perovskite solar cells. However, bis-PCBM is usually synthesized as a mixture of structural isomers, which can lead to both energetic and morphological disorder, negatively affecting device performance. Here, we present a comprehensive study on the molecular properties of 19 pure bis-isomers of PCBM using a variety of characterization methods, including ultraviolet photoelectron spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, single crystal structure, and (time-dependent) density functional theory calculation. We find that the lowest unoccupied molecular orbital of such bis-isomers can be tuned to be up to 170 meV shallower than PCBM and up to 100 meV shallower than the mixture of unseparated isomers. The isolated bis-isomers also show an electron mobility in organic field-effect transistors of up to 4.5 × 10-2 cm2/(V s), which is an order of magnitude higher than that of the mixture of bis-isomers. These properties enable the fabrication of the highest performing bis-PCBM organic solar cell to date, with the best device showing a power conversion efficiency of 7.2%. Interestingly, we find that the crystallinity of bis-isomers correlates negatively with electron mobility and organic solar cell device performance, which we relate to their molecular symmetry, with a lower symmetry leading to more amorphous bis-isomers, less energetic disorder, and higher dimensional electron transport. This work demonstrates the potential of side chain engineering for optimizing the performance of fullerene-based organic electronic devices.

Community interventions for improving adult mental health: mapping local policy and practice in England

BACKGROUND

Public mental health (PMH) aims to improve wellbeing and prevent poor mental health at the population level. It is a global challenge and a UK priority area for action. Communities play an important role in the provision of PMH interventions. However, the evidence base concerning community-based PMH interventions is limited, meaning it is challenging to compare service provision to need. Without this, the efficient and equitable provision of services is hindered. Here, we sought to map the current range of community-based interventions for improving mental health and wellbeing currently provided in England to inform priority areas for policy and service intervention.

METHOD

We adopted an established mapping exercise methodology, comparing service provision with demographic and deprivation statistics. Five local authority areas of England were selected based on differing demographics, mental health needs and wider challenging circumstances (i.e. high deprivation). Community-based interventions were identified through: 1) desk-based research 2) established professional networks 3) chain-referral sampling of individuals involved in local mental health promotion and prevention and 4) peer researchers' insight. We included all community-based, non-clinical interventions aimed at adult residents operating between July 2019 and May 2020.

RESULTS

407 interventions were identified across the five areas addressing 16 risk/protective factors for PMH. Interventions for social isolation and loneliness were most prevalent, most commonly through social activities and/or befriending services. The most common subpopulations targeted were older adults and people from minority ethnic backgrounds. Interventions focusing on broader structural and environmental determinants were uncommon. There was some evidence of service provision being tailored to local need, though this was inconsistent, meaning some at-risk groups such as men or LGBTQ+ people from minority ethnic backgrounds were missed. Interventions were not consistently evaluated.

CONCLUSIONS

There was evidence of partial responsiveness to national and local prioritising. Provision was geared mainly towards addressing social and individual determinants of PMH, suggesting more integration is needed to engage wider service providers and policy-makers in PMH strategy and delivery at the community level. The lack of comprehensive evaluation of services to improve PMH needs to be urgently addressed to determine the extent of their effectiveness in communities they serve.

Frailty: an in-depth qualitative study exploring the views of community care staff

Background

Frailty is seen across various health and social care settings. However, little is known about how healthcare professionals, particularly those who provide care for older adults living in the community view frailty. There is also a dearth of information about the extent to which a shared understanding of frailty exists across the various disciplines of care. Such an understanding is crucial across care professionals as it ensures consistent assessment of frailty and facilitates interdisciplinary working/collaboration which is a key component in the management of frailty. This study aimed to explore: (i) how community care staff from various specialties viewed frailty; (ii) whether they had a shared understanding; and (iii) how they assessed frailty in everyday practice.

Methods

Semi-structured interviews were conducted with a purposive sample of 22 community care staff from seven specialties, namely: healthcare assistants, therapy assistants, psychiatric nurses, general nurses, occupational therapists, physiotherapists and social workers, recruited from four neighbourhood teams across Cambridgeshire, England. Interviews were analysed thematically.

Results

There was a shared narrative among participants that frailty is an umbrella term that encompasses interacting physical, mental health and psychological, social, environmental, and economic factors. However, various specialities emphasised the role of specific facets of the frailty umbrella. The assessment and management of frailty was said to require a holistic approach facilitated by interdisciplinary working. Participants voiced a need for interdisciplinary training on frailty, and frailty tools that facilitate peer-learning, a shared understanding of frailty, and consistent assessment of frailty within and across specialities.

Conclusions

These findings underscore the need to: (i) move beyond biomedical descriptions of frailty; (ii) further explore the interacting nature of the various components of the frailty umbrella, particularly the role of modifiable factors such as psychological and socioeconomic resilience; (iii) care for frail older adults using holistic, interdisciplinary approaches; and (iv) promote interdisciplinary training around frailty and frailty tools to facilitate a shared understanding and consistent assessment of frailty within and across specialities.

Electronic supplementary material

The online version of this article (10.1186/s12877-019-1069-3) contains supplementary material, which is available to authorized users.

Identification of differentially expressed genes in human papillomavirus type-16 infected oral cancer cells

OBJECTIVE

The goal of this study was to determine the genes required for head and neck cancer development.

STUDY DESIGN AND SETTING

Differential mRNA display analysis was performed using human papillomavirus Type-16 infected immortalized human oral keratinocytes (HOK-16B) and its benzo(a)pyrene-exposed tumorigenic derivative (HOK-16B-BaP-T).

RESULTS

Twenty-one differentially expressed cDNA clones were identified between the 2 cell lines. Clone 4 with no known homology showed lower expression in tumorigenic cells compared with either normal or immortalized oral keratinocytes. Clone 6 expression was elevated in several head and neck cancer cells, in addition to Burkitt's lymphoma Raji harboring latent Epstein-Barr virus.

CONCLUSION

These findings suggested that clone 6 may be involved in the oncogenic transformation whereas clone 4 may potentially function as a tumor suppressor gene.

SIGNIFICANCE

Differential mRNA analysis using the in vitro oral carcinogenesis model may help to identify important genetic markers for the early detection and progression of head and neck cancer.