Spray-cast multilayer perovskite solar cells with an active-area of 1.5 cm(2)

We utilise spray-coating under ambient conditions to sequentially deposit compact-TiO2, mesoporous-TiO2, CH3NH3PbI(3-x)Clx perovskite and doped spiro-OMeTAD layers, creating a mesoporous standard architecture perovskite solar cell (PSC). The devices created had an average power conversion efficiency (PCE) of 9.2% and a peak PCE of 10.2%; values that compare favourably with control-devices fabricated by spin-casting that had an average efficiency of 11.4%. We show that our process can be used to create devices having an active-area of 1.5 cm(2) having an independently verified efficiency of 6.6%. This work demonstrates the versatility of spray-coating as well as its potential as a method of manufacturing low-cost, large-area, efficient perovskite devices

Plaque contact and unimpaired Trem2 is required for the microglial response to amyloid pathology

Using spatial cell-type-enriched transcriptomics, we compare plaque-induced gene (PIG) expression in microglia-touching plaques, neighboring plaques, and far from plaques in an aged Alzheimer’s mouse model with late plaque development. In 18-month-old APPNL-F/NL-F knockin mice, with and without the Alzheimer’s disease risk mutation Trem2R47H/R47H, we report that expression of 38/55 PIGs have plaque-induced microglial upregulation, with a subset only upregulating in microglia directly contacting plaques. For seven PIGs, including Trem2, this upregulation is prevented in APPNL-F/NL-FTrem2R47H/R47H mice. These TREM2-dependent genes are all involved in phagocytic and degradative processes that we show correspond to a decrease in phagocytic markers and an increase in the density of small plaques in Trem2-mutated mice. Furthermore, despite the R47H mutation preventing increased Trem2 gene expression, TREM2 protein levels and microglial density are still marginally increased on plaques. Hence, both microglial contact with plaques and functioning TREM2 are necessary for microglia to respond appropriately to amyloid patholog

Rapid scalable processing of tin oxide transport layers for perovskite solar cells

The development of scalable deposition methods for perovskite solar cell materials is critical to enable the commercialization of this nascent technology. Herein, we investigate the use and processing of nanoparticle SnO2 films as electron transport layers in perovskite solar cells and develop deposition methods for ultrasonic spray coating and slot-die coating, leading to photovoltaic device efficiencies over 19%. The effects of postprocessing treatments (thermal annealing, UV ozone, and O2 plasma) are then probed using structural and spectroscopic techniques to characterize the nature of the np-SnO2/perovskite interface. We show that a brief “hot air flow” method can be used to replace extended thermal annealing, confirming that this approach is compatible with high-throughput processing. Our results highlight the importance of interface management to minimize nonradiative losses and provide a deeper understanding of the processing requirements for large-area deposition of nanoparticle metal oxides

High-efficiency spray-coated perovskite solar cells utilizing vacuum-assisted solution processing

We use ultrasonic spray-coating to fabricate cesium-containing triple-cation perovskite solar cells with a power-conversion efficiency of up to 17.8%. Our fabrication route involves a brief exposure of the partially wet spray-cast films to a low vacuum, a process that is used to control film crystallization. We show that films that are not vacuum-exposed are relatively rough and inhomogeneous, while vacuum-exposed films are smooth and consist of small and densely packed perovskite crystals. The process techniques developed here represent a step toward a scalable and industrially compatible manufacturing process capable of creating stable and high-performance perovskite solar cells

Perovskite solar cells: a deep analysis using current–voltage and capacitance–voltage techniques

Perovskite solar cells exhibiting~14–15% efficiency were experimentally measured using current–voltage (I–V) and capacitance–voltage (C–V) techniques in order to extract material and device properties, and understand the action of photovoltaic (PV) operation. Deep analyses were carried out on dark- and illuminated I–V curves, and dark C–V curves. Results were compared with those of graded bandgap solar cells fabricated on inorganic n-type window layers. These analyses according to a physicist’s point of view lead to understand the perovskite solar cell as a graded bandgap solar cell built on a p-type window layer. I–V and C–V results show very similar behaviour and the principle of PV action is identical. Once the stability issues with perovskites are solved, these devices have very high potential of producing next generation solar cells reaching at least mid-20% efficiency values

High-Performance Multilayer Encapsulation for Perovskite Photovoltaics

An encapsulation system comprising of a UV‐curable epoxy, a solution processed polymer interlayer, and a glass cover‐slip, is used to increase the stability of methylammonium lead triiodide (CH3NH3PbI3) perovskite planar inverted architecture photovoltaic (PV) devices. It is found this encapsulation system acts as an efficient barrier to extrinsic degradation processes (ingress of moisture and oxygen), and that the polymer acts as a barrier that protects the PV device from the epoxy before it is fully cured. This results in devices that maintain 80% of their initial power conversion efficiency after 1000 h of AM1.5 irradiation. Such devices are used as a benchmark and are compared with devices having initially enhanced efficiency as a result of a solvent annealing process. It is found that such solvent‐annealed devices undergo enhanced burn‐in and have a reduced long‐term efficiency, a result demonstrating that initially enhanced device efficiency does not necessarily result in long‐term stability

The efficacy of four-slice helical CT in evaluating pancreatic trauma: a single institution experience

<p>Abstract</p> <p>Study objective</p> <p>To assess the efficacy of computed tomography (CT) in evaluating patients with pancreatic trauma.</p> <p>Methods</p> <p>We undertook a retrospective review of all blunt trauma patients admitted to the Chi-Mei Medical Center from January 2004 to June 2006. Every patients underwent abdominal CT scan in emergency department and the CT scans were obtained with a four-slice helical CT. Diagnosis of a pancreatic injury in these patients was by surgical observation or by CT findings. Radiographic pancreatic injuries were classified as deep or superficial lesions. Deep lesions were defined as the hematomas or lacerations >50% thickness of the pancreas. Superficial lesions were described as the hematomas or lacerations <50% thickness of the pancreas; pancreatic edema; and focal fluid accumulation around the pancreas</p> <p>Results</p> <p>Nineteen patients with pancreatic trauma, fourteen males and five females, average age 40.6 ± 21.4 years, were included. Most patients (73.7%) with pancreatic trauma had associated organ injuries. CT was performed in all patients and laparotomy in 14 patients. CT was 78.9% sensitive in detecting pancreatic trauma. All deep pancreatic lesions revealed on CT required surgical treatment, and complication was discovered in two patients undergoing delayed surgery. Superficial lesions were managed conservatively.</p> <p>Conclusion</p> <p>Four-slice helical CT can detect most pancreatic trauma and provide practical therapeutic guidance. Delayed operation might result in complications and is associated with prolonged hospital stays.</p

Engaging service users and carers in health and social care education: : challenges and opportunities in the Chinese Community

This is an accepted manuscript of an article published by Taylor & Francis Group in Social Work Education on 25 June 2010, available online at: http://dx.doi.org/10.1080/02615479.2010.491542.Service users' and carers' involvement in health and social care education has become a mainstream activity in Britain. However, members from black and minority ethnic communities (BME) remain under-represented in this area of participation. In this article, we will take the readers across the globe to explore the difficulties and opportunities of engaging such an under-represented group, the Chinese community. The journey will begin in Britain where barriers to engagement of service users and carers from the Chinese community will be discussed. We will then travel to Hong Kong, a cosmopolitan city, where successful engagement in work with Chinese service users and carers will be explored. Throughout the journey, we will highlight the importance of the consideration of cultural factors, particularly Confucian beliefs such as social harmony and collectivism, when working with Chinese people. We will also fully explore the issue of ‘trust’ as a culturally laden concept in Chinese societies and its significance for successful engagement in work with Chinese service users and carers in different parts of the world.Peer reviewedFinal Accepted Versio

Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development.

BACKGROUND: We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. RESULTS: The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. CONCLUSIONS: Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution

A flexible back-contact perovskite solar micro-module

Back-contact perovskite solar cells are fabricated by depositing methylammonium lead iodide perovskite into micron-sized grooves, with opposite walls of each groove being coated with either n- or p-type selective contacts. V-Shaped grooves are created by embossing a polymeric substrate, with the different charge-selective electrodes deposited onto the walls of the groove using a directional evaporation technique. We show that individual grooves act as photovoltaic devices, having a power conversion efficiency of up to 7.3%. By series-connecting multiple grooves, we create integrated micro-modules that build open circuit voltages up to nearly 15 V and power conversion efficiencies over 4%. The devices created are fully flexible, do not include rare metals, and are processed using techniques applicable to roll-to-roll processing