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GARNET LU-HF SPEED DATING: A NOVEL METHOD TO RAPIDLY RESOLVE POLYMETAMORPHIC HISTORIESAlexander Simpsona,, Stijn Gloriea,, Martin Handa,, Carl Spandlera, Sarah Gilberta,aDepartment of Earth Sciences, School of Physical Sciences, The University of Adelaide, Adelaide SA-5005, AustraliaAbstractGarnet is a remarkably useful mineral in the study of crustal and lithospheric-scale tectonic systems. A vast body of knowledge exists on its thermodynamic properties, meaning garnet is widely used for determining pressure-temperature conditions. Traditional methods to date garnet (e.g. Lu-Hf and Sm-Nd) are time consuming and commonly volumetrically imprecise. Consequently, garnet is generally now dated indirectly using co-existing minerals such as zircon and monazite that can be efficiently analysed using U-Pb age-dating, with their chemical compositions linked to garnet via inferred equilibrium elemental relationships. The disadvantage of this approach is the age of garnet is inferred, rather than directly determined, and it can be difficult to prove garnet grew contemporaneously with the dated U-Pb minerals. In situ Lu-Hf laser ablation dating of garnet is a comparatively recent development that embodies the efficiency of LAICPMS U-Pb dating. Here, we explore the use of laser ablation garnet Lu-Hf dating to rapidly reveal the metamorphic history of polymetamorphic terranes, producing accurate dates (in excellent agreement with published ages) with precisions as low as 1.5%. For instance, garnets analysed from the Moine supergroup, NW Scotland produce ages that coincide with all major orogenic evets (e.g. ~950 Ma Renlandian Orogeny, 810 - 740 Ma Knoydartian orogeny, and 470 – 420 Ma Caledonian Orogeny). In certain cases, two of these orogenic events are preserved in a single garnet grain, and the high spatial resolution of the laser method allows to accurately resolve such multi-growth histories. In addition, we demonstrate that the laser ablation Lu-Hf technique has the potential to evaluate micron-scale isotopic disturbances (such as diffusion) in garnet.

The ability to constrain the age of calcite formation is of great utility to the Earth science community, due to the ubiquity of calcite across a wide spectrum of geological systems. Here, we present the first in situ laser ablation inductively coupled tandem quadrupole mass spectrometry (LA-ICP-MS/MS) Lu–Hf ages for calcite, demonstrating geologically meaningful ages for iron oxide copper gold (IOCG) and skarn mineralisation, carbonatite intrusion, and low-grade metamorphism. The analysed samples range in age between ca. 0.9 and ca. 2 Ga with uncertainties between 1.7 % and 0.6 % obtained from calcite with Lu concentrations as low as ca. 0.5 ppm. The Lu–Hf system in calcite appears to be able to preserve primary precipitation ages over a significant amount of geological time, although further research is required to constrain the closure temperature. The in situ approach allows calcite to be rapidly dated while maintaining its petrogenetic context with mineralisation and other associated mineral processes. Therefore, LA-ICP-MS/MS Lu–Hf dating of calcite can be used to resolve the timing of complex mineral paragenetic sequences that are a feature of many ancient rock systems.

Recent developments in laser-ablation Lu–Hf dating have opened a new opportunity to rapidly obtain apatite ages that are potentially more robust to isotopic resetting compared to traditional U–Pb dating. However, the robustness of the apatite Lu–Hf system has not been systematically examined. To address this knowledge gap, we conducted four case studies to determine the resistivity of the apatite Lu–Hf system compared to the zircon and apatite U–Pb system. In all cases, the apatite U–Pb system records a secondary (metamorphic or metasomatic) overprint. The apatite Lu–Hf system, however, preserves primary crystallization ages in unfoliated granitoids at temperatures of at least c. 660°C. Above c. 730°C, the Lu–Hf system records isotopic resetting by volume diffusion. Hence, in our observations for apatites of ‘typical’ grain sizes in granitoids ( c. 0.01–0.03 mm 2 ), the closure temperature of the Lu–Hf system is between c. 660 and c. 730°C, consistent with theoretical calculations. In foliated granites, the Lu–Hf system records the timing of recrystallization, while the apatite U–Pb system tends to record younger cooling ages. We also present apatite Lu–Hf dates for lower crustal xenoliths erupted with young alkali basalts, demonstrating that the Lu–Hf system can retain a memory of primary ages when exposed to magmatic temperatures for a relatively short duration. Hence, the apatite Lu–Hf system is a new insightful addition to traditional zircon (or monazite) U–Pb dating, particularly when zircons/monazites are absent or difficult to interpret due to inheritance or when U and Pb isotopes display open system behaviour. The laser-ablation-based Lu–Hf method allows campaign-style studies to be conducted at a similar rate to U–Pb studies, opening new opportunities for magmatic and metamorphic studies.

Garnet is a fundamental expression of metamorphism and one of the most important minerals used to constrain the thermal conditions of the crust. We used innovative in situ laser-ablation ICP-MS/MS Lu-Hf geochronology to demonstrate that garnet in metapelitic rocks enclosing Cambrian eclogite in southern Australia formed during Laurentian Mesoproterozoic metamorphism. Garnet porphyroblasts in amphibolite-facies metapelitic rocks yielded Lu-Hf ages between 1286 ± 58 Ma and 1241 ± 16 Ma, revealing a record of older metamorphism that was partially obscured by metamorphic overprinting during ca. 510 Ma Cambrian subduction along the East Gondwana margin. Existing detrital zircon age data indicate the protoliths to the southern Australian metapelitic rocks were sourced from western Laurentia. We propose that the metapelitic rocks of southern Australia represent a fragment of western Laurentian crust, which was separated from Laurentia in the Neoproterozoic and incorporated into the East Gondwana subduction system during the Cambrian. The ability to obtain Lu-Hf isotopic data from garnet at acquisition rates comparable to those for U-Pb analysis of detrital zircon means, for the first time, the metamorphic parentage of rocks as expressed by garnet can be efficiently accessed to assist paleogeographic reconstructions.

Large igneous provinces (LIPs) are often used as a powerful tool for constraining continental reconstructions, due to their potential to correlate radiometric emplacement ages across scattered fragments of once continuous igneous bodies, and establish the presence of coeval magmatic suites. Mesoproterozoic magmatism in northern Australia and north China has been suggested to be the dispersed fragments of a once contiguous LIP. Here we present new geochronology and geochemical data from the under-resolved northern Australian fragments of this province (the Derim Derim and Galiwinku suites), and review existing data on related Mesoproterozoic mafic sills in the North Australian Craton and the North China Craton. We propose an updated framework for shared magmatic genesis and cratonic proximity during magmatic emplacement. Apatite geochronology has been applied to date dolerite intrusions, using cogenetic minerals to constrain the initial common-Pb constraints of the dolerite samples which provides a significant advantage for dating mafic rocks. The ages of samples collected throughout the extent of the mafic magmatic province in northern Australia and north China supports coincident ca. 1330–1295 Ma magmatism across both regions, while geochemical evidence indicates a mantle plume derived melt as the probable source for both suites. Coeval intrusion of geochemically analogous sills within temporally and stratigraphically comparable sedimentary basins is supportive of plume activity proximal to a once continuous sedimentary system that covered much of the North Australian Craton and North China Craton, which supports a close connection between the cratons within the supercontinent Nuna in the Mesoproterozoic.

BackgroundMedical assistance in dying (MAiD) traverses challenging and emotionally overwhelming territories: healthcare providers (HCPs) across jurisdictions experience myriad of affective responses secondary to possible tensions between normative and interwoven values, such as sanctity of life, dignity in death and dying and duty to care.ObjectiveTo determine the emotional impact on HCPs involved in MAiD.MethodsInclusion restricted to English language qualitative research studies from four databases (OVID Medline, EMBASE, CINAHL and Scopus), from beginning until 30 April 2021, and grey literature up to August 2021 were searched. Key author, citation and reference searches were undertaken. We excluded studies without rigorous qualitative research methodology. Included studies were critically appraised using the Joanna Briggs Institute’s critical appraisal tool. Analysis was conducted using thematic meta-synthesis. The cumulative evidence was assessed for confidence using the Confidence in the Evidence from Reviews of Qualitative Research approach.ResultsThe search identified 4522 papers. Data from 35 studies (393 physicians, 169 nurses, 53 social workers, 22 allied healthcare professionals) employing diverse qualitative research methodologies from five countries were coded and analysed. The thematic meta-synthesis showed three descriptive emotional themes: (1) polarised emotions including moral distress (n=153), (2) reflective emotions with MAiD as a ‘sense-making process’ (n=251), and (3) professional value-driven emotions (n=352).DiscussionThis research attempts to answer the question, ‘what it means at an emotional level’, for a MAiD practitioner. Legislation allowing MAiD for terminal illness only influences the emotional impact: MAiD practitioners under this essential criterion experience more polarised emotions, whereas those practising in jurisdictions with greater emphasis on allaying intolerable suffering experience more reflective emotions. MAiD practitioner’s professional values and their degree of engagement influence the emotional impact, which may help structure future support networks. English language literature restriction and absence of subgroup analyses limit the generalisability of results.

Garnet is a fundamental expression of metamorphism and one of the most important minerals used to constrain the thermal conditions of the crust. Here, we use innovative in-situ laser ablation ICP–MS/MS Lu–Hf geochronology to demonstrate that garnet in metapelitic rocks enclosing Cambrian eclogite in southern Australia formed during Laurentian Mesoproterozoic metamorphism. Garnet porphyroblasts in amphibolite-facies metapelitic rocks yield Lu–Hf ages between c. 1285 and 1240 Ma, revealing a record of older metamorphism that has been partially obscured by metamorphic overprinting during c. 510 Ma Cambrian subduction along the East Gondwana margin. Existing detrital zircon age data indicate the protoliths to the southern Australian metapelitic rocks were sourced from western Laurentia. We propose that the metapelitic rocks of southern Australia represent a fragment of western Laurentian crust, which was separated from Laurentia in the Neoproterozoic and incorporated into the East Gondwana subduction system during the Cambrian. The ability to obtain Lu–Hf isotopic data from garnet at acquisition rates comparable to those for U–Pb analysis of detrital zircon means, for the first time, the metamorphic parentage of rocks as expressed by garnet can be efficiently accessed to assist palaeogeographic reconstructions.

The development of in situ laser ablation Lu–Hf geochronology of apatite, xenotime and garnet has opened avenues to directly date mineral-forming geological processes. We demonstrate the first use of campaign-style in situ Lu–Hf geochronology of garnet across the high- to ultrahigh-pressure Western Gneiss Region in Norway. Mafic eclogites from this region have been the focus of much work, and were clearly formed during continental subduction during the Caledonian Orogeny. However, abundant quartzofeldspathic and pelitic lithologies record a more complex history, with some preserving polymetamorphic age data, and most containing no indication of high-pressure mineral assemblages formed during subduction. In this study, twenty metapelitic and felsic samples spanning 160 lateral kilometres across the Western Gneiss Region have been analysed using garnet Lu–Hf geochronology. The results reveal Caledonian ages for the majority of the garnets, suggesting that some quartzofeldspathic and metapelitic lithologies were reactive and grew garnet during high- to ultrahigh-pressure metamorphism. However, two ultrahigh-pressure eclogite locations, Verpeneset and Fjørtoft, preserve both Caledonian and Neoproterozoic-aged garnet. This polymetamorphism is recorded across different garnet grains within the same lithology, or within single polymetamorphic garnets. Despite significant uncertainties on some of the Lu–Hf geochronological ages, laser ablation Lu–Hf efficiently identifies the polymetamorphic history of parts of the Western Gneiss Region, illustrating the effectiveness of this novel analytical method for rapid mapping of metamorphic ages.

Detrital geochronology is a powerful tool to interrogate the sedimentary archive of (paleo-)hinterland tectonic, metamorphic, and climatic processes, and can also be applied to modern river sediment as a first-pass tool to establish regional bedrock ages. The popular zircon U-Pb detrital geochronometer has seen widespread adoption for these tasks (3,626/4,471 results for the search term detrital geochronology also contain the term zircon U-Pb; Clarivate Analytics Web of Science). However, zircon fertility is strongly biased to intermediate to felsic source rocks. Moreover, zircon crystallization is volumetrically limited in metamorphic terranes which do not achieve anataxis (e.g., Moecher & Samson, 2006), and is typically restricted to rim overgrowths which are vulnerable to mechanical destruction during fluvial transport, and which are challenging to detect and analyse (e.g., Campbell et al., 2005).Therefore, it is desirable to develop complementary provenance tools for metamorphic settings. Garnet group minerals are rock-forming in several common metamorphic lithologies, and garnet is therefore a common constituent of clastic detritus from orogens. Moreover, single-grain in-situ dating of garnet by LA-ICPMS is possible using the U-Pb (e.g., Seman et al., 2017) and, by use of an online reaction cell, the Lu-Hf radioisotope systems (Simpson et al., 2021). Here, we present results from U-Pb and Lu-Hf double-dating, acquired by LA-ICPMS for detrital garnet recovered from the Oligo-Miocene pro-foreland basin of the European Alps, as well as modern Alpine river sediment. We integrate these data with compositional data acquired by Raman spectroscopy, and energy and wavelength-dispersive X-ray spectroscopy (Stutenbecker et al., 2019). We discuss the implications for Alpine tectonics and metamorphism, and future scope of detrital garnet geochronometry. Campbell, I., et al., 2005. Earth Planet. Sci. Lett. 237, 402-432, doi: 10.1016/j.epsl.2005.06.043Moecher, D., & Samson, S., 2006, Earth Planet. Sci. Lett. 247, 252–266, doi: 10.1016/j.epsl.2006.04.035Seman, S., et al., 2017. Chem. Geol. 460, 106–116. doi: 10.1016/j.chemgeo.2017.04.020Simpson, A., et al., 2021. Chem. Geol. 577, 120299. doi: 10.1016/j.chemgeo.2021.120299Stutenbecker, L., et al., 2019, Solid Earth 10, 1581–1595, doi: 10.5194/se-10-1581-2019

Deciphering the tectono-metamorphic evolution of Precambrian terranes can be difficult due to reworking by later superimposed events. Whole-rock elemental and isotopic geochemistry and zircon U–Pb geochronology are often employed in those studies, but these approaches are often not sensitive to the presence of multiple events and medium-grade metamorphic episodes. The Rio Apa Terrane (RAT), an allochthonous fragment of the Amazonian Craton, is a crustal block with a well-characterized crustal evolution but with no detailed thermal constraints for its tectono-metamorphic evolution. In contrast to previous studies, we show the existence of four tectono-metamorphic events at c. 1,780, c. 1,625, c. 1,420–1,340, and c. 1,300–1,200 Ma on the basis of apatite, titanite, and rutile U–Pb, in situ white-mica Rb–Sr, and in situ garnet Lu–Hf geochronology combined with mineral chemistry and phase-equilibria modelling. The c. 1,780 Ma event is recorded in the basement of the Western domain, representing an extensional event coeval with the development of its Eastern domain in response to the retreat stage of the accretionary system. This is followed by juxtaposition of the Western and Eastern domains along a major crustal boundary at c. 1,625 Ma, which is defined by the magnetic profiles and zircon U–Pb–Hf data across the boundary. The third and fourth events correspond to progressive high-pressure/medium-temperature (HP/MT) metamorphism, characterized by an anticlockwise P–T path, suggesting a convergent-to-collisional tectonic setting. The RAT was accreted to the adjoining Paraguá Terrane at c. 1,420–1,340 Ma under an isobaric P–T evolution spanning ~530°C to 600°C and ~10.0 kbar. Subsequently, the combined Rio Apa and Paraguá terranes collided with the SW Amazonian Craton at c. 1,300–1,200 Ma, reaching P–T conditions of ~560–580°C and ~10.9–11.7 kbar during crustal thickening. This study reveals for the first time the existence of a HP/MT metamorphic evolution related to the growth of the SW Amazonian Craton as part of an accretionary orogenic system during Rodinia assembly in the Palaeoproterozoic to Mesoproterozoic.

The development of in situ laser ablation Lu–Hf geochronology of apatite, xenotime and garnet has opened avenues to quickly and directly date geological processes. We demonstrate the first use of campaign-style in situ Lu–Hf geochronology of garnet across the high- to ultrahigh-pressure Western Gneiss Region in Norway. Mafic eclogites from this region have been the focus of much work, and were clearly formed during continental subduction during the Caledonian Orogeny. However, abundant quartzofeldspathic and pelitic lithologies record a more complex history, with some preserving polymetamorphic age data, and most containing no indication of high-pressure mineral assemblages formed during subduction. Twenty metapelitic and felsic samples spanning 160 lateral kilometres across the Western Gneiss Region have been analysed using garnet Lu–Hf geochronology. The results reveal Caledonian ages for the majority of the garnets, suggesting that some quartzofeldspathic and metapelitic lithologies were reactive and grew garnet during high- to ultrahigh-pressure metamorphism. However, two ultrahigh-pressure eclogite locations, Verpeneset and Fjørtoft, preserve both Caledonian and Neoproterozoic-aged garnets. Despite significant uncertainties on some of the Lu–Hf geochronological ages, laser ablation Lu–Hf efficiently identifies the polymetamorphic history of parts of the Western Gneiss Region, illustrating the effectiveness of this novel analytical method for rapid mapping of metamorphic ages. Supplementary material: All laser ablation Lu–Hf geochronological data for the garnets analysed in this study are available at https://doi.org/10.6084/m9.figshare.c.5715453 Thematic collection: This article is part of the Caledonian Wilson cycle collection available at: https://www.lyellcollection.org/cc/caledonian-wilson-cycle

Alzheimer’s disease-associated amyloid beta (Aβ) proteins accumulate in the outer retina with increasing age and in eyes of age-related macular degeneration (AMD) patients. To study Aβ-induced retinopathy, wild-type mice were injected with nanomolar human oligomeric Aβ1-42, which recapitulate the Aβ burden reported in human donor eyes. In vitro studies investigated the cellular effects of Aβ in endothelial and retinal pigment epithelial (RPE) cells. Results show subretinal Aβ-induced focal AMD-like pathology within 2 weeks. Aβ exposure caused endothelial cell migration, and morphological and barrier alterations to the RPE. Aβ co-localized to late-endocytic compartments of RPE cells, which persisted despite attempts to clear it through upregulation of lysosomal cathepsin B, revealing a novel mechanism of lysosomal impairment in retinal degeneration. The rapid upregulation of cathepsin B was out of step with the prolonged accumulation of Aβ within lysosomes, and contrasted with enzymatic responses to internalized photoreceptor outer segments (POS). Furthermore, RPE cells exposed to Aβ were identified as deficient in cargo-carrying lysosomes at time points that are critical to POS degradation. These findings imply that Aβ accumulation within late-endocytic compartments, as well as lysosomal deficiency, impairs RPE function over time, contributing to visual defects seen in aging and AMD eyes.

Background Physicians are in a position of great influence to advocate for health equity. As such, it is important for physicians-in-training to develop the knowledge and skills necessary to fulfil this role. Although various undergraduate medical programs have implemented health advocacy training, they often lack experiential learning and physician involvement. These aspects are foundational to the Advocacy Mentorship Initiative (AMI) which utilizes cascading mentorship as a novel approach to advocacy training. Medical students develop advocacy competency as peer mentors to youth raised in at-risk environments, while also being mentored themselves by physician residents. We aim to determine whether there are specific advantages to utilizing cascading mentorship to facilitate the attainment of advocacy competencies in undergraduate medical education. Methods Medical students participating in AMI between 2017 to 2020 completed pre- and post-exposure questionnaires. Questionnaires assessed confidence in advocacy-related skills and knowledge of youth advocacy concepts, as well as learning goals, skills gained, benefits of AMI and resident mentors, and impact on future career. Sign tests were utilized to analyze quantitative results, and content analysis was used for open-ended responses. A triangulation protocol was also utilized. Results Fifty mentors participated, 24 (48%) of which completed both pre- and post-exposure questionnaires. Participants gained confidence in advocacy-related skills (ppConclusions AMI offers a unique method of advocacy training through cascading mentorship that engages medical students both as mentors to at-risk youth and mentees to resident physicians. Through cascading mentorship, medical students advance in their advocacy-related skills and understanding of social determinants of health.

Given the general absence of suitable direct dating methods, the timing of low-temperature crustal deformation is usually established by indirect methods (such as apatite fission track (AFT) thermo...

Lu Hf geochronology is a powerful method to constrain the temporal evolution of geological systems. Traditional application of this dating method requires time-consuming chemical separation of the parent (176Lu) and daughter (176Hf) isotopes that is commonly accompanied by loss of textural context of the analysed minerals. In contrast, In-situ (laser-ablation based) Lu Hf geochronology offers a number of advantages including rapid analysis with high spatial resolution, as well as control on textural relationships of the analysed mineral. However, laser-ablation based Lu Hf geochronology has been hindered by isobaric interferences of 176Yb and 176Lu on 176Hf that have effectively masked reliable determination of 176Lu and 176Hf. We present a methodology that resolves these interferences using LA-ICP-MS/MS (laser ablation tandem inductively coupled mass spectrometry) and NH3 gas to separate Hf from Lu. Both Lu, Yb, and Hf react with NH3 to form a variety of product ions. By measuring high order reaction products (e.g. Hf(NH)(NH2)(NH3)3+), we demonstrate that 176Hf can be measured interference-free from 176Lu and 176Yb with sufficient sensitivity to yield useful geochronological age data. The novel in-situ Lu Hf technique has been successfully applied to a variety of Palaeozoic and Precambrian-aged garnet, apatite and xenotime samples, including published reference materials. The resulting age uncertainties are as low as ~0.5% (95% conf. interval). The technique has the potential to obtain spatially-resolved Lu Hf ages in garnet-bearing samples that would be difficult to obtain by conventional techniques. The method also offers the opportunity for rapid “campaign style” geochronology in complex terrains that record poly-metamorphic histories. In apatite, the expected higher closure temperature of the Lu Hf system compared to the commonly used U Pb system allows high-temperature thermal history reconstructions. In addition, Lu Hf dating of apatite allows dating of samples with low U and high common Pb (e.g. mafic and low-grade metamorphic rocks and ore deposits). Furthermore, apatite tends to incorporate little to no common Hf, allowing single grain ages to be calculated, which opens new doors for detrital provenance studies. In situ Lu Hf dating of xenotime offers an additional avenue to U Pb dating, and may be particularly beneficial to dating of rare earth element ore deposits that often have complex temporal records of development.

Purpose We explore the challenges of the secondary use of data in clinical information systems which critical care units in the National Health Service (England) are facing. Methods We conducted an online survey of critical care units in England regarding their practices in collecting and using clinical information systems and data. Results Critical care units use clinical information systems typically independently of hospital information systems and focus mainly on using data for auditing, management reporting and research. Respondents reported that extracting data from their clinical information system was difficult and that they would use stored data more if it were easier to access. Data extraction takes time and who extracts data, the training they receive and the tools they use affect the extraction and use of data. Conclusion A number of key challenges affect the secondary use of data in critical care: a lack of integration of information systems within critical care and across departments; barriers to accessing data; mismatched data tools and user requests. Data are predominantly used for reporting and research with less emphasis on using data to inform clinical practice.

Adopting a strong process perspective, this chapter seeks to problematize the way in which data are typically conceived in the information sciences and in contemporary organizational discourse. Drawing on evidence from an ongoing multidisciplinary study of data reuse in acute healthcare we argue that, contrary to the prevalent conception of data as a fundamental, natural resource that exists “out there” in the world, data are constituted through complex activities and transactions. They are a contingent record of a contingent selection of what is paid attention to in the world. Not all data that are recorded, moreover, may be looked for, and of these not all may be found or be accessible. Much of what gets described as data are therefore “data in principle” only, with just a proportion becoming “data in practice,” able to contribute to organizational processes. Some implications of this process view of data are explored.

This work describes advanced metrology based on Single Particle Inductively Coupled Plasma Mass Spectrometry (sp- ICP-MS) used in chemical mechanical planarization (CMP) process development. sp-ICP-MS was used to measure concentrations and sizes of ceria nanoparticles before and after CMP of silicon dioxide. Changes in the particle size distribution show a shift to lower median particle size after polishing, and an increase in the number of smaller particles. This result is consistent with previous reports which showed significant in- process reduction of the average ceria particle size after polishing. These new results are important because they demonstrate the application of sp-ICP-MS in the development of advanced CMP processes.

The extreme density of DNA presents a compelling advantage over current storage media; however, in order to reach practical capacities, new approaches for organizing and accessing information are needed. Here we use chemical handles to selectively extract unique files from a complex database of DNA mimicking 5 TB of data and design and implement a nested file address system that increases the theoretical maximum capacity of DNA storage systems by five orders of magnitude. These advancements enable the development and future scaling of DNA-based data storage systems with reasonable modern capacities and file access capabilities.

This work describes advanced metrology based on Single Particle Inductively Coupled Plasma Mass Spectrometry (spICP-MS) for evaluating ultra-pure chemicals used in electronics applications such as Chemical Mechanical Planarization (CMP), cleaning fluids, photoresist, anti-reflecting coatings etc. spICP-MS was used to measure concentrations and sizes of nanoparticles both upstream and downstream of sub 100 nm rated membranes. One membrane showed over 1000-fold reduction of gold particles sized between 14 and 80 nm. spICP-MS was also used to study ceria nanoparticles before and after CMP of silicon dioxide. Changes in the ceria particle size distributions after CMP showed a relative increase in the concentration of smaller particles. These results demonstrate the application of spICP-MS for the characterization of particles in fluids used in the advanced semiconductor wafer processing.

This work describes the use of Single Particle Inductively Coupled Plasma Mass Spectrometry (spICP-MS) to measure ceria particle number concentrations and compare changes in size distributions to silicon dioxide wafer removal rates from different chemical mechanical planarization (CMP) processes. Particle number concentrations were measured for the 21 to 559 nm size range at 1 nm size resolution. Changes in the ceria particle size distribution after CMP included a decrease in large (>130 nm) particles, an increase in small (2 = 0.96) for a series of pad types with unique combinations of chemistry and surface features. This new combination of nano particle metrology and control of pad surface features is an innovative tool set for modeling advanced CMP processes.

U-Pb dating of calcite veins allows direct dating of brittle deformation events. Here, we apply this method to hydrothermal calcite veins in a fold-and-thrust belt and a large scale strike-slip fault zone in central and western Thailand, in an attempt to shed new light on the regional upper crustal deformation history. Calcite U-Pb dates for the Khao Khwang Fold and Thrust Belt (KKFTB) of 221 ± 7 Ma and 216 ± 3 Ma demonstrate that calcite precipitated during tectonic activity associated with stage II of the Indosinian Orogeny (Late Triassic – Early Jurassic). One additional sample from the KKFTB suggests that the Indosinian calcite has locally been overprinted by a Cenozoic fluid event with a different chemistry. For the Three Pagodas Fault Zone (TPFZ), our calcite U-Pb results suggest a complex, protracted history of Cenozoic brittle deformation. Petrographic information combined with contrasting redox-sensitive trace elemental signatures suggest that the vein arrays in the TPFZ precipitated during two distinct events of brittle deformation at ~48 and ~23 Ma. These dates are interpreted in the context of far-field brittle deformation related to the India-Eurasia collision. The presented calcite U-Pb dates are in excellent agreement with published age constraints on the deformation history of Thailand, demonstrating the utility of the method to decipher complex brittle deformation histories. The paper further illustrates some of the complexities in relation to calcite U-Pb dating and provides suggestions for untangling complex datasets that could be applied to future studies on the deformation history of Thailand and other regions.

Thirty years ago, forensic investigation was spoken of almost religiously, a multibranched philosophy that could—with enough practice, enough patience, and enough attention to detail—positively identify who committed a crime beyond a reasonable doubt. The abilities of forensic experts to solve crimes were so strongly believed that they became the subject of countless television shows, both real and fictional. “CSI” alone has four spin-off series, each more spectacular than the last, all of them depicting dedicated and (more importantly) altogether unerring crime scene analysts who always found their man by the end of the hour. Forensic investigation was seen, in the eyes of the public at least, as nothing short of a miracle for police work. It could be used to solve cold cases, which had previously stymied law enforcement; it could completely destroy a defendant's alibi; it could definitively prove guilt by analyzing a piece of evidence invisible to the naked eye. This chapter will review the principles and practice of the forensic sciences from law enforcement, prosecution, and defense perspectives.

Unmanned Micro Aerial Vehicles (MAVs) have the potential to operate in diverse environments but are limited by the lack of robust algorithms for autonomous flight. This is largely due to the sensing and processing requirements that exceed the weight and power limitations of this hardware. Recent research has highlighted the potential to overcome these constraints by looking to the natural world, in particular to the possibilities of using optical flow. This work presents a novel biomimetic algorithm that uses optical flow data generated from the on-board camera of a quadcopter MAV to avoid obstacles in flight. Simulation results are presented showing the algorithm performance in a range of flying scenarios. This work also highlights the huge potential of using low resolution sensors and lightweight algorithms in the field of autonomous vehicle control.

To examine insulin regimens and factors that affect glycaemic control at 6 months after initiation of insulin therapy in patients with type 2 diabetes mellitus.Information on patients requiring insulin initiation as part of usual care was collected in a prospective, observational, open-label study in five European countries. Univariate and multiple regression analyses were used to investigate factors associated with HbA1c achieved at 6 months.Mean HbA1c for all patients at baseline was 9.6 ± 1.8%. Long/intermediate-acting insulin only was most commonly initiated in France and Spain, while long/intermediate or pre-mixed formulations were initiated in Greece and UK. This was consistent with guidelines used in those countries and there was little change in insulin regimen at 6 months in these countries. In Germany, short-acting insulin only was favoured at baseline and there was a shift towards basal/bolus regimens at 6 months, which reflected the local guidelines for insulin initiation in Germany. Mean HbA1c reduction was greatest in Germany (-2.3%), which was the only country to achieve a mean of7% at 6 months. In all countries, HbA1c achieved at 6 months was associated with baseline HbA1c. Differences between countries were seen for influence of factors such as BMI, duration of diabetes, insulin regimen, insulin dose and number of oral anti-diabetes drugs on HbA1c achieved. Explained variability for the factors ranged from 5.6% to 22.9%.Differences in insulin regimen were observed between countries, and appeared to reflect the guidelines and treatment regimens used.

The Skiddaw Slates consist of eight formations with the substantial thickness of about 30,000 ft. This geosynclinal sequence is of Arenig age though the highest formation may continue into the Lower Llanvirn. The polyphase tectonics of the Skiddaw Slates and the relationship of the overlying Borrowdale Volcanic Series are discussed. It is concluded that the Caledonian tectonic history of this part of Britain contains two paroxysms of orogenic activity. In addition to the orthodox end-Silurian orogenesis there was also an intra-Lower Ordovician orogenic episode which took place towards the close of the Llanvirn. During the earlier tectonic climax the Skiddaw Slates were deformed by two phases of folding. Their structure is, therefore, largely of pre-Borrowdale age and bears little relation to that of the overlying cover. After this dual deformation the slaty basement was truncated by erosion and is separated from the overlying Borrowdale Volcanic Series by an angular unconformity. Only the end-Silurian folding affects the volcanic superstructure and the younger Lower Palaeozoic sequence.