Aspects of electronic device packaging

For this work cordierite has been investigated as a possible substitute substrate material for alumina, with particular emphasis on its role in multilayer device packaging. By limiting the processing temperatures to below 1000oC, copper could be used as the conductor material. Milled glass powder was made into thin sheet form by a doctor blading technique and, once dried, the copper screen printed on top. After lamination and firing, the conductor was completely encapsulated by the cordierite matrix. Copper diffusion occ~red with metallic copper precipitating out although a small denuded zone was evident around the periphery of the conductor. This was due to compositional changes occurring there. Experiment showed that the effects of glass particle shape, average size and size distribution lead to deviation in the shrinking of compacts from the theoretical sintering curves. An unstable ~ phase was the first to appear on the glass particle surfaces although another, unidentifiable phase, was also found to exist during the very early stages of crystallization. This was followed shortly after by bulk crystallization of ~ cordierite in the remaining glass, possibly being aided by a prior phase separation. Further heat treatment lead to the transformation to a cordie rite and the formation of enstatite, the exact transformation temperature depending upon the minor oxide additives in the glass. At temperatures above ~10500C protoenstatite formed and lead to a general degradation in material properties. The benefit from having a cordie rite as the principal phase is a low dielectric constant (5.35) and loss angle (5 x 10-4), reasonable strength (130 MPa) and high resistivity (~1015 Qcm). This makes it a suitable replacement for alumina although its low thermal conductivity (~2 Wm-lK-l) is a drawback. By adjusting the MgO/A1203 ratio, the material could be expansion matched to that of silicon

What do dendrochronology and other timber-dating methods tell us about the history of English post mills?

Post mills are a distinctive type of windmill that has had a long history in England. Today only 47 post mills still survive in England. Evidence from 15 of these where their timbers have been subjected to dendrochronological investigations combined with other sources of evidence helps build a picture of the history of each of these mills. Most mills contain timbers from different historical rebuilding phases, but with the main posts often being the oldest component. Bourn Windmill was the earliest of these (the tree from which the main post was made being felled sometime after 1515) but Nutley and Pitstone mills retain almost equally ancient main posts. Scientific timber-dating methods can help corroborate the historical narrative derived from other evidence, such as documentary sources or inscriptions; however, they can also help raise completely new questions, illuminating stages in the history of a structure that were previously unknown or unsuspected

Acropora - The most-studied coral genus

Over the last 2 million years, Acropora (the staghorn or elkhorn corals) has become the dominant genus of reef-building corals throughout the Indo-Pacific. Like other coral genera, Acropora taxonomy is presently undergoing comprehensive revision as a consequence of large-scale sequencing projects, which will substantially alter our understanding of the diversity and biogeography of the group. Acropora spp. are among the most stress sensitive of corals, and as a consequence, population declines are occurring worldwide, most significantly due to global warming. Despite diverse adult colony morphology, all members of the genus are similar at the tissue and polyp level and follow common reproductive and developmental programs. Some progress has recently been made in development of gene knockdown/knockout methods despite the long generation times of corals and need to rely on natural spawning events. Since 2018, the number of Acropora genome sequences available has increased dramatically, although taxonomic uncertainties complicate their evolutionary interpretation. Areas of particularly active research include settlement and the control of metamorphosis; metabolic interactions with both bacterial and eukaryotic symbionts, particularly Symbiodinaceae, and their gain and loss; and how best to restore reefs destroyed by storms and coral bleaching

Differential efficacy of vaccinia virus envelope proteins administered by DNA immunisation in protection of BALB/c mice from a lethal intranasal poxvirus challenge

DNA vaccines might offer an alternative to the live smallpox vaccine in providing protective efficacy in an orthopoxvirus (OPV) lethal respiratory challenge model. BALB/c mice were immunised with DNA vaccines coding for 10 different single vaccinia virus (VACV) membrane proteins. After an intranasal challenge with the VACV IHD strain, three gene candidates B5R, A33R and A27L produced > or =66% survival. The B5R DNA vaccine consistently produced 100% protection and exhibited greatest efficacy after three 50 microg intramuscular doses in this model. Sero-conversion to these vaccines was often inconsistent, implying that antibody itself was not a correlate of protection. The B5R DNA vaccine induced a strong and consistent gamma interferon (IFNgamma) response in BALB/c mice given a single DNA vaccine dose. Strong IFNgamma responses were also measured in pTB5R immunised C57BL6 mice deficient for MHC class I molecules, suggesting that the memory response was mediated by a CD4+ T cell population

e-Tendering readiness in construction: the posterior model

Purpose: To verified a conceptual model for e-Tendering readiness in any construction organisation prior to implementation. Design/methodology/approach: Based on the conceptual model called e-Tendering readiness model (e-TRM), this paper empirically examines the e-TRM’s interactions and causal relationships between e-Tendering constructs and e-Tendering readiness. Structural equation modelling is used to test the hypothesised positive inter-relationships. A questionnaire survey is conducted of construction organisations in Saudi Arabia to understand their current e-Tendering readiness and importance of e-Tendering variables. Findings: Supported by empirical evidence, the paper recognises that three out of nine constructs have a direct influence on e-Tendering readiness. One of the constructs is hypothesised for the first time and turns out to have the most effect when tested. Research limitations/implications: The empirical test for the e-TRM is restricted to Saudi Arabia which, though not atypical of most countries’ e-tendering around the world, needs to be further tested in other areas for additional verification. Practical implications: To update previous IT/IS models in construction by adding this tested model to the research literature on traditional and electronic tendering and the body of knowledge in the construction industry. Originality/value: The Service Providers construct is proposed and tested for the first time, which is necessary to support the successful e-Tendering implementation

Spitzer infrared spectrometer 16μm observations of the GOODS fields

We present Spitzer 16μm imaging of the Great Observatories Origins Deep Survey (GOODS) fields. We survey 150 arcmin^2 in each of the two GOODS fields (North and South), to an average 3σ depth of 40 and 65 μJy, respectively. We detect ~1300 sources in both fields combined. We validate the photometry using the 3–24μm spectral energy distribution of stars in the fields compared to Spitzer spectroscopic templates. Comparison with ISOCAM and AKARI observations in the same fields shows reasonable agreement, though the uncertainties are large. We provide a catalog of photometry, with sources cross-correlated with available Spitzer, Chandra, and Hubble Space Telescope data. Galaxy number counts show good agreement with previous results from ISOCAM and AKARI with improved uncertainties. We examine the 16–24μm flux ratio and find that for most sources it lies within the expected locus for starbursts and infrared luminous galaxies. A color cut of S_(16)/S_(24) > 1.4 selects mostly sources which lie at 1.1 < z < 1.6, where the 24μm passband contains both the redshifted 9.7 μm silicate absorption and the minimum between polycyclic aromatic hydrocarbon emission peaks. We measure the integrated galaxy light of 16μm sources and find a lower limit on the galaxy contribution to the extragalactic background light at this wavelength to be 2.2 ± 0.2 nW m^(−2) sr^(−1)

Post-hurricane building damage assessment using street-view imagery and structured data: A multi-modal deep learning approach

Accurately assessing building damage is critical for disaster response and recovery. However, many existing models for detecting building damage have poor prediction accuracy due to their limited capabilities of identifying detailed, comprehensive structural and/or non-structural damage from the street-view image. Additionally, these models mainly rely on the imagery data for damage classification, failing to account for other critical information, such as wind speed, building characteristics, evacuation zones, and distance of the building to the hurricane track. To address these limitations, in this study, we propose a novel multi-modal (i.e., imagery and structured data) approach for post-hurricane building damage classification, named the Multi-Modal Swin Transformer (MMST). We empirically train and evaluate the proposed MMST using data collected from the 2022 Hurricane Ian in Florida, USA. Results show that MMST outperforms all selected state-of-the-art benchmark models and can achieve an accuracy of 92.67%, which are 7.71% improvement in accuracy compared to Visual Geometry Group 16 (VGG-16). In addition to the street-view imagery data, building value, building age, and wind speed are the most important predictors for damage level classification. The proposed MMST can be deployed to assist in rapid damage assessment and guide reconnaissance efforts in future hurricanes

HCV and the hepatic lipid pathway as a potential treatment target

Atherosclerosis has been described as a liver disease of the heart. The liver is the central regulatory organ of lipid pathways but since dyslipidaemias are major contributors to cardiovascular disease and type 2 diabetes rather than liver disease, research in this area has not been a major focus for hepatologists. Virus-host interaction is a continuous co-evolutionary process involving the host immune system and viral escape mechanisms. One of the strategies HCV has adopted to escape immune clearance and establish persistent infection is to make use of hepatic lipid pathways. This review aims to: update the hepatologist on lipid metabolism; review the evidence that HCV exploits hepatic lipid pathways to its advantage; discuss approaches to targeting host lipid pathways as adjunctive therapy