An Investigation into the Energy Performance Gap between the Predicted and Measured Output of Photovoltaic Systems Using Dynamic Simulation Modelling Software – A Case Study

The use of solar energy can help reduce the CO2 emission and dependency on fossil fuels, and using Solar Photovoltaic (PV) systems to generate electricity is a popular route to validate the building energy performance in the UK. To help achieve the targets set out in the Climate Change Act, Part L of the Building Regulations 2013 stated that a building must achieve the approved minimum energy performance requirements. EDSL Tas, a dynamic modelling software, is often used by building consultant companies whose designers use the facility to simulate PV systems and integrate the energy output results into the overall energy performance of a building. There is, however, a clear performance gap between the measured and predicted energy output when using dynamic modelling software. Therefore, this paper is to use a comparative study to address this issue by using EDSL Tas software to predict PV system’s energy output and comprehensively analyse a case study at Poole Methodist Church. There are many causes for the potential deviation of results, although the most influential in relation to energy performance is the use of weather data, future climate change, adverse weather conditions and environmental factors affecting the PV array. The results indicate an 8.6% higher measured energy output from the installed PV system although the performance gap has little detrimental effect in regards to achieving Building Regulation compliance, but could lead to the unreasonable design of the PV system and inappropriate use of capital investment. Further simulation using projected future weather data from several different climate change scenarios was undertaken. 2020, 2050 and 2080 with low, medium and high emission scenarios indicated that the PV array would increase energy output by up to 5% by 2080 compared with using current weather data, indicating a rise in PV energy output in relation to increased CO₂ emissions. This is due to a projected reduction in cloud cover and increased downward shortwave radiation

Offsetting of CO₂ emissions by air capture in mine tailings at the Mount Keith Nickel Mine, Western Australia: Rates, controls and prospects for carbon neutral mining

The hydrated Mg-carbonate mineral, hydromagnesite [Mg₅(CO₃)₄(OH)₂•4H₂O], precipitates within mine tailings at the Mount Keith Nickel Mine, Western Australia as a direct result of mining operations. We have used quantitative mineralogical data and δ¹³C, δ¹⁸O and F¹⁴C isotopic data to quantify the amount of CO₂fixation and identify carbon sources. Our radiocarbon results indicate that at least 80% of carbon stored in hydromagnesite has been captured from the modern atmosphere. Stable isotopic results indicate that dissolution of atmospheric CO₂ into mine tailings water is kinetically limited, which suggests that the current rate of carbon mineralization could be accelerated. Reactive transport modeling is used to describe the observed variation in tailings mineralogy and to estimate rates of CO₂ fixation. Based on our assessment, approximately 39,800 t/yr of atmospheric CO₂ are being trapped and stored in tailings at Mount Keith. This represents an offsetting of approximately 11% of the mine's annual greenhouse gas emissions. Thus, passive sequestration via enhanced weathering of mineral waste can capture and store a significant amount of CO₂. Recommendations are made for changes to tailings management and ore processing practices that have potential to accelerate carbonation of tailings and further reduce or completely offset the net greenhouse gas emissions at Mount Keith and many other mines

Rotating with the brakes on and other unresolved features of the vacuolar ATPase

Abstract The rotary ATPase family comprises the ATP synthase (F-ATPase), vacuolar ATPase (V-ATPase) and archaeal ATPase (A-ATPase). These either predominantly utilize a proton gradient for ATP synthesis or use ATP to produce a proton gradient, driving secondary transport and acidifying organelles. With advances in EM has come a significant increase in our understanding of the rotary ATPase family. Following the sub nm resolution reconstructions of both the F-and V-ATPases, the secondary structure organization of the elusive subunit a has now been resolved, revealing a novel helical arrangement. Despite these significant developments in our understanding of the rotary ATPases, there are still a number of unresolved questions about the mechanism, regulation and overall architecture, which this mini-review aims to highlight and discuss

Dynamic clonal progression in xenografts of acute lymphoblastic leukemia with intrachromosomal amplification of chromosome 21

Intrachromosomal amplification of chromosome 21 is a heterogeneous chromosomal rearrangement occurring in 2% of childhood precursor B-cell acute lymphoblastic leukemia. There are no cell lines with iAMP21 and these abnormalities are too complex to faithfully engineer in animal models. As a resource for future functional and pre-clinical studies, we have created xenografts from intrachromosomal amplification of chromosome 21 leukemia patient blasts and characterised them by in-vivo and ex-vivo luminescent imaging, FLOW immunophenotyping, and histological and ultrastructural analysis of bone marrow and the central nervous system. Investigation of up to three generations of xenografts revealed phenotypic evolution, branching genomic architecture and, compared with other B-cell acute lymphoblastic leukemia genetic subtypes, greater clonal diversity of leukemia initiating cells. In support of intrachromosomal amplification of chromosome 21 as a primary genetic abnormality, it was always retained through generations of xenografts, although we also observed the first example of structural evolution of this rearrangement. Clonal segregation in xenografts revealed convergent evolution of different secondary genomic abnormalities implicating several known tumour suppressor genes and a region, containing the B-cell adaptor, PIK3AP1, and nuclear receptor co-repressor, LCOR, in the progression of B-ALL. Tracking of mutations in patients and derived xenografts provided evidence for co-operation between abnormalities activating the RAS pathway in B-ALL and for their aggressive clonal expansion in the xeno-environment. Bi-allelic loss of the CDKN2A/B locus was recurrently maintained or emergent in xenografts and also strongly selected as RNA sequencing demonstrated a complete absence of reads for genes associated with the deletions

Designing Technology-Mediated Peer Support for Postgraduate Research Students at Risk of Loneliness and Isolation

Student mental health and wellbeing have come under increased scrutiny in recent years. Postgraduate research (PGR) students are at risk of experiencing mental health concerns and this, with the often isolated and competitive nature of their work, can impact their sense of community and social connectedness. In response to these concerns, we designed Pears, a system to connect PGR students for regular "pearings"(in-person meetings) and provide activities to promote reflection and conversation. A four-week evaluation of Pears with 15 students highlighted its potential to sometimes, but not always, facilitate peer support. Some participants would instead meet formally and according to their needs, others instead used the system to make new social connections. Additionally, some participants who faced work-related difficulties during the study found using the system contributed to their stress levels. We conclude by noting how technologies that encourage peer support can help build social relationships, providing an avenue to share similar PhD experiences and guidance for those new to the experience, while importantly raising awareness and an understanding for the need to take time for self-care. However, these technologies must be utilised carefully, and are not a replacement for other sources of student support in universities.</p

Different weak interactions in the crystals of three isomeric (E)-N-methyl-N0-(nitrobenzylidene)- 2-(thiophen-2-yl)acetohydrazides

We thank the EPSRC National Crystallography Service (University of Southampton) for X-ray data collection.Peer reviewedPublisher PD

An investigation into the energy performance gap between the predicted and measured output of photovoltaic systems using dynamic simulation modelling software—a case study

The use of solar energy can help reduce CO₂ emissions and dependency on fossil fuels, and using Solar Photovoltaic (PV) systems to generate electricity is a popular route to decarbonisation in the UK. To help achieve the targets set out in the Climate Change Act, building service consultants often use EDSL Tas, a dynamic modelling software, to simulate PV systems and integrate the energy output results into the overall energy performance of a building. There is, however, a clear performance gap between the measured and predicted energy output. There are many causes for the potential deviation of results, although the most influential in relation to energy performance is the use of weather data, future climate change, adverse weather conditions and environmental factors affecting the PV array. The results through a case study indicated an 8.6% higher measured energy output from the installed PV system although the performance gap has little detrimental effect regarding achieving Building Regulation compliance, but could lead to the unreasonable design of the PV system and inappropriate use of capital investment. Further simulation using projected future weather data from several different climate change scenarios was undertaken. 2020, 2050 and 2080 with low, medium and high emission scenarios indicated that the PV array would increase energy output by up to 5% by 2080 compared with using current weather data, indicating a rise in PV energy output in relation to increased CO₂ emissions. This is due to a projected reduction in cloud cover and increased downward shortwave radiation

The Dominant Australian Community-Acquired Methicillin-Resistant Staphylococcus aureus Clone ST93-IV [2B] Is Highly Virulent and Genetically Distinct

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) USA300 has spread rapidly across North America, and CA-MRSA is also increasing in Australia. However, the dominant Australian CA-MRSA strain, ST93-IV [2B] appears distantly related to USA300 despite strikingly similar clinical and epidemiological profiles. Here, we compared the virulence of a recent Australian ST93 isolate (JKD6159) to other MRSA, including USA300, and found that JKD6159 was the most virulent in a mouse skin infection model. We fully sequenced the genome of JKD6159 and confirmed that JKD6159 is a distinct clone with 7616 single nucleotide polymorphisms (SNPs) distinguishing this strain from all other S. aureus genomes. Despite its high virulence there were surprisingly few virulence determinants. However, genes encoding α-hemolysin, Panton-Valentine leukocidin (PVL) and α-type phenol soluble modulins were present. Genome comparisons revealed 32 additional CDS in JKD6159 but none appeared to encode new virulence factors, suggesting that this clone's enhanced pathogenicity could lie within subtler genome changes, such as SNPs within regulatory genes. To investigate the role of accessory genome elements in CA-MRSA epidemiology, we next sequenced three additional Australian non-ST93 CA-MRSA strains and compared them with JKD6159, 19 completed S. aureus genomes and 59 additional S. aureus genomes for which unassembled genome sequence data was publicly available (82 genomes in total). These comparisons showed that despite its distinctive genotype, JKD6159 and other CA-MRSA clones (including USA300) share a conserved repertoire of three notable accessory elements (SSCmecIV, PVL prophage, and pMW2). This study demonstrates that the genetically distinct ST93 CA-MRSA from Australia is highly virulent. Our comparisons of geographically and genetically diverse CA-MRSA genomes suggest that apparent convergent evolution in CA-MRSA may be better explained by the rapid dissemination of a highly conserved accessory genome from a common source

Gay Community Periodic Survey: Queensland 2005

Gay Community Periodic Surveys surveys are regularly conducted in Sydney, Melbourne, Brisbane, Cairns, Canberra, Adelaide and Perth to monitor changes in sexual and other risk practices over time among Australian gay men who are gay community attached, recruited from gay sex-on-premises venues, social sites and clinics