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Porous silicon layers on wafers are commonly converted into particles by mechanical milling or ultrasonic fragmentation. The former technique can rapidly generate large batches of microparticles. The latter technique is commonly used for making nanoparticles but processing times are very long and yields, where reported, are often very low. With both processing techniques, the porosity and surface area of the particles generated are often assumed to be similar to those of the parent film. We demonstrate that this is rarely the case, using air-dried high porosity and supercritically dried aerocrystals as examples. We show that whereas ball milling can more quickly generate much higher yields of particles, it is much more damaging to the nanostructures than ultrasonic fragmentation. The latter technique is particularly promising for silicon aerocrystals since processing times are reduced whilst yields are simultaneously raised with ultrahigh porosity structures. Not only that, but very high surface areas (> 500 m2/g) can be completely preserved with ultrasonic fragmentation. [ABSTRACT FROM AUTHOR]

InGaAs/InP double-heterostructure P–i–N diodes of various junction areas are characterized at room temperature and modeled using TCAD. Biasing the guard ring allows one to quantify the dark current contributions to the central diode from Shockley–Read–Hall (SRH) generation in the depletion region as well as the junction perimeter leakage. The latter is determined to be 1.4 ± 0.3 pA/cm based on an interface trap density of 106 cm−2 at the InGaAs/InP interface, whereas the depletion region contributes 2.0 ± 0.2 nA/cm2 based on a nonradiative SRH lifetime of 0.8 ms. Unbiasing the test structures results in up to an order of magnitude increase in dark current due to minority carrier diffusion; modeling yields a minority carrier diffusion length of 70 µm, which is in agreement with the experimentally extracted value of (65 ± 5) µm using separate test structures on the same wafer. This corresponds to a hole mobility of 570 cm2/Vs at room temperature for a doping concentration of 5 × 1015 cm−3. The calibrated model is then verified by predicting the dark current of 25 × 25 and 15 × 15 μm2 pixels; the results are in good agreement compared to measurements of 100 pixel test arrays. [ABSTRACT FROM AUTHOR]

Objective: The PARENTS 1 study (Parents' Active Role and ENgagement in The review of their Stillbirth/perinatal death) found that parents would endorse the opportunity to give feedback into the perinatal mortality review (PNMR) process. In subsequent focus groups, healthcare professionals were positive about parental engagement, although they considered that there may be significant challenges. The objective of this study was to develop core principles and recommendations for parental engagement in PNMR in the UK.Methods: A two-round Delphi technique was followed to reach consensus on core principles for parental engagement in the PNMR process; Round 1 included a national consensus workshop and Round 2 an online questionnaire. The consensus meeting was attended by a national panel of stakeholders (clinical and academic experts, parent advocates, managers and commissioners) in stillbirth and neonatal and bereavement care. To develop recommendations for parental engagement, participants discussed four key areas comprising: communication with parents, including receiving feedback; the format of the PNMR meeting; the parental engagement pathway; and challenging aspects of engaging with parents in reviews. Content analysis was conducted to generate recommendations from the meeting for a subsequent anonymous web-based survey. Attendees of the consensus workshop and members of the PARENTS 2 Project Advisory Board were asked to rank recommendations using a 9-point Likert scale from 1 (not important) to 9 (critically important). It had been agreed a priori, in compliance with established Grading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria, that 'consensus' would be achieved if over 70% of participants scored the principle as 'critical' (score of 7-9) and fewer than 15% scored the principle as 'not important' (score of 1-3). Principles for which consensus was achieved were included in the core recommendations.Results: Of the 29 invited stakeholders, 22 participated in the consensus meeting and 25 (86% response rate) in the subsequent online questionnaire in June 2017. Consensus was agreed on 12 core principles. Of the 25 participants, 96% agreed that a face-to-face explanation of the PNMR process was of critical importance, 72% considered that parents should be offered the opportunity to nominate a suitable advocate, 92% believed that responses to parents' comments should be formally documented, 96% indicated that it was vital for action plans to be translated into lessons learnt and that this process should be monitored, and 100% of stakeholders voted that a plain-English summary should be produced for the parents following the meeting. There was good agreement on a further seven principles.Conclusions: Key national stakeholders were unanimously supportive of parental engagement in the PNMR process and agreed on core principles to make this process feasible, meaningful and robust. A 6-month pilot of parental engagement in the PNMR process (PARENTS 2 study) in two UK units took place after the consensus on core principles. In collaboration with the National Perinatal Epidemiology Unit, the findings will inform the national standardized PNMR tool. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

In order to investigate visitor perceptions of dust, dirt and cleaning in historic houses, visitors were invited to be a 'researcher' for the day at an historic house and photograph what they felt to be a conservation need. This self-directed photo survey provided a useful communication tool between visitors, researchers, conservators and collection care staff. The method generated specific and actionable feedback about the focus of visitors' attention, their perception of risk in the historic environment and the impact of conservation plans on the visitor experience. Although the non-expert nature of visitors' observations was clear, there was new insight into what visitors find attractive, alarming or anomalous in a historic house environment. This accessible and inclusive method is potentially easily conducted by staff and volunteers involved in collections care. The results could be used to inform training, prioritisation, presentation and interpretation, as well as conservation. [ABSTRACT FROM AUTHOR]

Background: Stillbirth has a profound impact on women, families, and healthcare workers. The burden is highest in low- and middle-income countries (LMICs). There is need for respectful and supportive care for women, partners, and families after bereavement.Objective: To perform a qualitative meta-summary of parents' and healthcare professionals' experiences of care after stillbirth in LMICs.Search Strategy: Search terms were formulated by identifying all synonyms, thesaurus terms, and variations for stillbirth. Databases searched were AMED, EMBASE, MEDLINE, PsychINFO, BNI, CINAHL.Selection Criteria: Qualitative, quantitative, and mixed method studies that addressed parents' or healthcare professionals' experience of care after stillbirth in LMICs.Data Collection and Analysis: Studies were screened, and data extracted in duplicate. Data were analysed using the Sandelowski meta-summary technique that calculates frequency and intensity effect sizes (FES/IES).Main Results: In all, 118 full texts were screened, and 34 studies from 17 countries were included. FES range was 15-68%. Most studies had IES 1.5-4.5. Women experience a broad range of manifestations of grief following stillbirth, which may not be recognised by healthcare workers or in their communities. Lack of recognition exacerbates negative experiences of stigmatisation, blame, devaluation, and loss of social status. Adequately developed health systems, with trained and supported staff, are best equipped to provide the support and information that women want after stillbirth.Conclusions: Basic interventions could have an immediate impact on the experiences of women and their families after stillbirth. Examples include public education to reduce stigma, promoting the respectful maternity care agenda, and investigating stillbirth appropriately.Tweetable Abstract: Reducing stigma, promoting respectful care and investigating stillbirth have a positive impact after stillbirth for women and families in LMICs. [ABSTRACT FROM AUTHOR]

The spectacular kilometer‐thick Funzie Conglomerate is a deformed and metamorphosed high‐energy sedimentary deposit that occurs in Shetland (Scottish Caledonides). Its age and tectonic significance in relation to Early Ordovician (485–475 Ma) and Late Ordovician (450–445 Ma) accretionary orogenic events and the culminating Silurian (430–425 Ma) continental collision and closure of the Iapetus Ocean have hitherto been unknown. U‐Pb zircon dating indicates that the clast population of the conglomerate was derived from easterly sources comprising Neoproterozoic metasedimentary rocks and the northern extension of the Ordovician‐Silurian Midland Valley Arc that formed during Iapetus closure. A lower age limit of 440 Ma is indicated by the ages of the youngest matrix detrital zircon grains and the youngest granitic clast. Deformation and metamorphism of the conglomerate is attributed to sinistrally oblique extension at ca. 430 Ma that excised at least 10 km of crustal section. Sedimentation of the conglomerate is therefore constrained to a 10‐myr time span (440–430 Ma). The tectonic setting is interpreted as a synorogenic basin that received detritus from, and was buried by, advancing thrust nappes during the Early Silurian collision of Laurentia and Baltica. Tectonic burial was followed rapidly by ductile deformation during oblique extensional unroofing of the metamorphic pile and accounts for preservation of the Funzie Conglomerate as a rare example of a synorogenic basin within the metamorphic hinterland of the North Atlantic Caledonides. Key Points: U‐Pb zircon dating in combination with published mineral age data shows that the deformed and metamorphosed Funzie Conglomerate in Shetland, Scottish Caledonides, was deposited in the Early Silurian between ca. 440 and 430 MaThe clast population was derived from easterly (offshore) sources comprising Neoproterozoic metasedimentary rocks and the northern extension of the Ordovician Midland Valley Arc that formed during closure of the Iapetus OceanThe tectonic setting is interpreted as a synorogenic basin that received detritus from, and was buried by, advancing thrust nappes during the collision of Laurentia and Baltica [ABSTRACT FROM AUTHOR]

Objective: To assess the frequency of additional care, and parents' perceptions of quality, respectful care, in pregnancies subsequent to stillbirth.Design: Multi-language web-based survey.Setting: International.Population: A total of 2716 parents, from 40 high- and middle-income countries.Methods: Data were obtained from a broader survey of parents' experiences following stillbirth. Data were analysed using descriptive statistics and stratified by geographic region. Subgroup analyses explored variation in additional care by gestational age at index stillbirth.Main Outcome Measures: Frequency of additional care, and perceptions of quality, respectful care.Results: The majority (66%) of parents conceived their subsequent pregnancy within 1 year of stillbirth. Additional antenatal care visits and ultrasound scans were provided for 67% and 70% of all parents, respectively, although there was wide variation across geographic regions. Care addressing psychosocial needs was less frequently provided, such as additional visits to a bereavement counsellor (10%) and access to named care provider's phone number (27%). Compared with parents whose stillbirth occurred at ≤ 29 weeks of gestation, parents whose stillbirth occurred at ≥ 30 weeks of gestation were more likely to receive various forms of additional care, particularly the option for early delivery after 37 weeks. Around half (47-63%) of all parents felt that elements of quality, respectful care were consistently applied, such as spending enough time with parents and involving parents in decision-making.Conclusions: Greater attention is required to providing thoughtful, empathic and collaborative care in all pregnancies following stillbirth. Specific education and training for health professionals is needed.Tweetable Abstract: More support for providing quality care in pregnancies after stillbirth is needed.Plain Language Summary: Study rationale and design More than two million babies are stillborn every year. Most parents will conceive again soon after having a stillborn baby. These parents are more likely to have another stillborn baby in the next pregnancy than parents who have not had a stillborn baby before. The next pregnancy after stillbirth is often an extremely anxious time for parents, as they worry about whether their baby will survive. In this study we asked 2716 parents from 40 countries about the care they received during their first pregnancy after stillbirth. Parents were recruited mainly through the International Stillbirth Alliance and completed on online survey that was available in six languages. Findings Parents often had extra antenatal visits and extra ultrasound scans in the next pregnancy, but they rarely had extra emotional support. Also, many parents felt their care providers did not always listen to them and spend enough time with them, involve them in decisions, and take their concerns seriously. Parents were more likely to receive various forms of extra care in the next pregnancy if their baby had died later in pregnancy compared to earlier in pregnancy. Limitations In this study we only have information from parents who were able and willing to complete an online survey. Most of the parents were involved in charity and support groups and most parents lived in developed countries. We do not know how well the findings relate to other parents. Finally, our study does not include parents who may have tried for another pregnancy but were not able to conceive. Potential impact This study can help to improve care through the development of best practice guidelines for pregnancies following stillbirth. The results suggest that parents need better emotional support in these pregnancies, and more opportunities to participate actively in decisions about care. Extra support should be available no matter how far along in pregnancy the previous stillborn baby died. [ABSTRACT FROM AUTHOR]

Objective: To understand challenges in care after stillbirth and provide tailored solutions.Design: Multi-centre case study.Setting: Three maternity hospitals.Population: Parents with a stillborn baby, maternity staff.Methods: Thematic analysis of parent interviews and staff focus groups and service provision investigation.Outcomes: 1 Themes; 2 Triangulation matrix; 3 Recommendations.Results: Twenty-one women, 14 partners, and 22 staff participated. Service Provision: Care for parents after stillbirth varies excessively; there are misconceptions; post-mortem does not delay follow-up.Presentation: Women 'do not feel right' before stillbirth; their management is haphazard and should be standardised.Diagnosis: Stillbirth is an emergency for parents but not always for staff; communication can seem cold; well-designed bereavement space is critical. Birth: Staff shift priorities to mother and future, but for parents their baby is still a baby; parents are not comfortable with staff recommending vaginal birth as the norm; there are several reasons why parents ask for a caesarean; better care involves clear communication, normal behaviour, and discussion of coping strategies. Post-mortem: Parents are influenced by discussions with staff. Staff should 'sow seeds', clarify its respectful nature, delineate its purpose, and explain the timescale.Follow-up: It is not standardised; parents wish to see their multi-professional team.Conclusions: There is unacceptable variation in care after stillbirth, and insensitive interactions between staff and bereaved parents. Understanding parents' needs, including why they ask for caesarean birth, will facilitate joint decision-making. Every bereaved parent is entitled to good, respectful care.Tweetable Abstract: Care too varied & interactions often insensitive after stillbirth; national pathway & training urgently needed PLAIN LANGUAGE SUMMARY: Why and how was the study carried out? Previous studies have shown that improving care after stillbirth is important for families. We investigated the opinions of bereaved parents and maternity staff to find ways to improve care. At three hospitals in 2013, all women who experienced a stillbirth were invited to an interview along with their partners. Thirty-five parents of 21 babies agreed to participate. Twenty-two obstetricians and midwives took part in focus group discussions. What were the main findings? Care was often not as good as it should and could be. Communication with parents was not always as sensitive as they would have liked because staff did not have appropriate training. Some women reported they did not 'feel right' before going to hospital. Once they arrived, there was no standard approach to how care was given. Sometimes there were long delays before the death of the baby was confirmed and action was taken. After it had been confirmed that the baby had died, staff focussed on the mothers' needs, but the parents' priorities were still with their baby. There were several reasons why parents asked for a caesarean birth that staff had not considered. Staff influenced parents' decisions about post-mortem examinations. Parents found it helpful when staff explained the respectful nature and purpose of the examination. After discharge from hospital, there was no consistent plan for how follow-up care would be given. Parents would have liked more information about their next hospital appointment. What are the limitations of the work? The parents interviewed depended on their memories of the details of the care, which happened some time ago. In staff group discussions, junior doctors may not have spoken openly because there were senior doctors present. Further research is necessary to understand and improve care globally. What is the implication for parents? Every bereaved parent is entitled to the best possible care after stillbirth, but some do not get good care. Parents and staff made suggestions that can help to develop processes for how care is given after stillbirth. These suggestions can also inform staff training, so that every single parent is treated respectfully and participates in decision making. [ABSTRACT FROM AUTHOR]

A methodology for chemical routes development and evaluation on the basis of data-mining is presented. A section of the Reaxys database was converted into a network, which was used to plan hypothetical synthesis routes to convert a bio-waste feedstock, limonene, to a bulk intermediate, benzoic acid. The route evaluation considered process conditions and used multiple indicators, including exergy, E-factor, solvent score, reaction reliability and route redox efficiency, in a multi-criteria environmental sustainability evaluation. The proposed methodology is the first route evaluation based on data mining, explicitly using reaction conditions, and is amenable to full automation. [ABSTRACT FROM AUTHOR]

Many phosphate-based glasses (PBGs) for biomaterial applications have been developed from the Na2O-CaO-P2O5 system. The common base compositions for PBGs are (55-x)Na2O-xCaO-45P2O5 and 20Na2O.30CaO.50P2O5, where the latter corresponds to a metaphosphate, and there is a wealth of experimental data for 50Na2O.50P2O5, 50CaO.50P2O5 and 20Na2O.30CaO.50P2O5 metaphosphate glasses. A classical molecular dynamics (MD) method has been used to model Na2O-CaO-P2O5 glass structures, and the results have been closely compared with experimental data for the same glasses. The MD models show the phosphate network to be dominated by Q² units, as expected, and to have short range order parameters that are in good agreement with neutron and x-ray diffraction results. Typical coordination numbers of Na and Ca are 5 and 6, respectively. The modifier cation distributions have been examined in detail through the correlation functions TMM(r), with M=Na and/or Ca. The TMM(r) functions show the expected dependence of peak position on modifier cation size, and peak height on modifier cation concentration. The numbers of M-M nearest neighbours are in agreement with a statistical model, in which modifier cations are bonded to nonbridging oxygens, Onb, and M(Onb)N polyhedra are predominantly connected to each other by corner-sharing. [ABSTRACT FROM AUTHOR]

The authors discuss prevalence and prevention of stillbirths in response to the 2017 Every Woman Every Child (EWEC) progress report on the global strategy developed for women's and children's health. Topics explored include the occurrence of stillbirths in low- and middle-income nations, the integration of health interventions into maternal and newborn care practices, and the need to acknowledge psychological and psychosocial impact of stillbirths.

Introduction: Apatite is widely used to evaluate the origin, abundance, and evolution of volatile species in plantary bodies [1], provide thermochronological constraints on geological processes and meteorite impact events [2, 3] and track magmatic evolution through trace element and isotopic studies [4]. This is due to the incorporation of volatile species in apatite group minerals, hexagonal Ca5[PO4]3[F,Cl,OH], and the fact that it is a principal carrier of a widerange of trace elements such as rare earth elements, uranium, and thorium in many planetary crustal rocks. Despite this wide-ranging importance, the in-situ measurement of many of these chemical records in apatite remains challenging. Specific analytical issues include the migration of volatiles (including halogens), and related crystallographic orientation effects, during electron beam interaction, and the requirement to integrate data from several approaches with different analytical volumes (e.g. major elements by EPMA, halogens, and isotope ratios by SIMS, NanoSIMS, LA-ICP-MS, etc.). Here we report on the development of a new approach to the concurrent acquisition of halogens, major & trace elements, and U-Th-Pb isotope ratios in apatite group minerals at the 20 to 30 µm scale, using tandem femtosecond laser ablation (LA) and laser-induced breakdown spectroscopy (LIBS) coupled with ICP-MS. Analytical approach: Analyses are being performed at the University of Portsmouth, using an Applied Spectra J200 Tandem LA-LIBS system that is equipped with a 343 nm femtosecond laser source, novel two-volume ablation and LIBS cell design, and two intensified CCD spectrometers. Terrestrial apatite reference materials with a wide-range of chlorine and fluorine compositions are being used to optimize laser and spectrometer detection conditions for the measurement of the major elements Ca and P, along with F by LIBS, and concurrent analysis of Cl, a wide-range of trace elements, and U-Th-Pb isotope ratios using an Agilent 8900 ICP-MS/MS system (building on the LA-ICP-MS protocols of [5, 6]). Analyses are being performed with the laser-focused to either 20 or 30 µm on the sample, fluences between 5 and 10 Jcm-2, and laser repetition rate of 10 Hz (200 shots total). Progress and opportunities: Although previous LIBS studies have determined F contents in phosphates using the 685.6 nm atomic emission line [7], we find only weak emission of halogen atomic lines using our analytical setup. This is not particularly unexpected, as these emissions require high excitation energies (and hence laser conditions) that are not well suited to LA-ICP-MS analyses. Alternatively, alkali earth-halogen molecular emission can be used to quantify F contents by LIBS [8]. Here, we focus on CaF molecular emission at ~532 nm. The dual ICCD spectrometer setup of the LIBS system allows for optimization of P and Ca atomic emission lines at a relatively short gate delay (~0.1 µs; length of time between the laser pulse and the spectrometer detection), and separation of CaF molecular emission from potentially interfering atomic and ionic emission lines using longer gate delay (>0.3 µs). As a result, background-corrected count rates for CaF are in the Mcps range from terrestrial fluorapatite, and we report on the accuracy and detection limits of LIBS calibration of F, along with Ca and P for use as independently determined internal standard elements for LA-ICP-MS trace element measurements. Initial results from terrestrial reference materials show the tremendous potential of the technique to enable concurrent halogen, major, trace, and U-Th-Pb geochronology from terrestrial and planetary apatite. [ABSTRACT FROM AUTHOR]

The Rogart and Strontian high Ba–Sr plutons (Northern Highlands, Scotland) comprise a range of lithologies from felsic to ultramafic rocks. The latter are mantle-derived and their differentiation to produce the felsic components of the plutons is the result of fractional crystallization and variable assimilation of the surrounding Moine metasediments. New results presented here demonstrate that accessory mineral chemistry can provide further insight into their petrogenesis and highlight the petrological potential of apatite and titanite. The main accessory minerals titanite, apatite and zircon contain most of the rare earth elements (REE) in the high Ba–Sr plutons. Results for apatite and titanite show that careful imaging and in situ trace element analysis provide constraints on the petrogenetic history of the host-rock. In both plutons, apatite and titanite record in situ crystallization and fractionation. In Strontian, both apatite and titanite from the granitoids record a mixing event with mafic magma in their rim compositions. Apatite and titanite chemistries are sensitive to the nature of their host-rocks (felsic versus ultramafic) and some elements (e.g. Sr, V) closely reflect whole-rock chemistry and the degree of fractionation. In some cases, whole-rock trace element concentrations can be calculated based on accessory mineral chemistry. Thus, trace elements in accessory minerals can give direct access to the nature and crystallization history of plutonic rocks. This petrological tool may be helpful in provenance studies using accessory minerals, and because high Ba–Sr plutons have recently been equated with Archaean sanukitoids, this might also be important in constraining the temporal distribution of this important magma type. [ABSTRACT FROM AUTHOR]

Voluminous rhyolitic lavas and ignimbrites (c. 34 000 km3) were formed in the NE German Basin in a post-collisional setting at c. 295 Ma. Trace elements, ϵHf and δ18O have been measured in dated magmatic and inherited rhyolitic zircons from three drill cores across the basin. Magmatic zircons crystallized in two stages: the first stage in less differentiated and isotopically heterogeneous magmas and the second stage in more differentiated and isotopically homogeneous magmas. The first and second stages can be related to the crystallization of zircons within a heterogeneous pluton and in an evolved, silicic magma that was later erupted. Some zircons crystallized entirely during the evolved magma stage and provide good resolution for identifying and characterizing processes happening shortly before eruption. The isotopic compositions of the magmatic zircons constrain the proportions of juvenile and reworked materials involved in the formation of voluminous silicic magmas in a post-collisional tectonic setting. The advantage of studying the volcanic rocks from the NE German Basin is that their petrogenesis involved a relatively simple, two-source interaction during magma production, which permits quantitative estimation of the amount of each source component. AFC modelling shows that the first stage zircons crystallized from magmas containing 5–80% of the juvenile component, whereas the final rhyolitic magmas contained 30–40% of this material. The inherited zircons have Hf model ages of 1·9–2·2 Ga, suggesting that much of the local basement was initially derived from the mantle at that time and that it was subsequently reworked at around 1·5 Ga. Similar model ages are a feature of Baltica-derived sediments and the implication is that such sediments underlie large areas of the NE German Basin. The lack of any record of Avalonian basement in the NE German Basin may indicate that both the sedimentary cover and the underlying basement are part of Baltica. [ABSTRACT FROM AUTHOR]

Assessment for source of stroke is a common indication for transoesophageal echocardiography (TOE). Although an abnormality is frequently found, it remains uncertain how frequently the findings alter patient management. Also, the role of transthoracic echocardiography (TTE) prior to or instead of TOE is not well defined. We sought to determine the use of TTE prior to TOE, the outcome of the TOE and its impact on management. We retrospectively reviewed the records and echocardiography results of 100 consecutive patients who underwent TOE for any reason at a tertiary hospital. In 35 subjects (35%), the indication was evaluation for source of stroke. Among these, we determined clinical risk factors for stroke, if a TTE was performed prior to their TOE, the results of the TOE and its effect on management. The mean age of the stroke patients was 64.6 years (17-90) and 49% were women. Eighty per cent had at least one risk factor for stroke and 17% had atrial fibrillation. A TTE, performed in 40% prior to the TOE, found an abnormality in 14% (2/14). The TOE showed an abnormality in 71% of patients; 54% had aortic atheroma; 17% PFO; 14% spontaneous echo contrast; 6% left atrial appendage thrombus, 3% left ventricular thrombus and 3% vegetation. In only one patient (3%) the management was altered based on the abnormal TOE findings. An abnormality on TOE, although common (71%) and more sensitive than TTE, altered management in only 3% of subjects referred for stroke assessment. Its role requires further consideration. [ABSTRACT FROM AUTHOR]

Information on the roundtable discussion regarding the politics of policy making in palliative medicine industry in the U.S. is presented. The discussion is attended by prominent people in palliative treatment like physicians Diane E. Meier, Walter J. Smith and David J. Casarett. One of the issues highlighted in the roundtable is the radioactivity of palliative care.

Aim: To investigate employment policies in England to encourage retention of primary and community nurses over the age of 50 years.Background: Little is known about why older nurses in the primary and community workforce leave or what might encourage them to stay.Methods: Fifteen telephone interviews with staff with responsibility for the nursing workforce in five primary care trusts (PCTs) and associated Workforce Development Confederations and Strategic Health Authorities.Results: When older nurses left, there was concern about the loss of skills, experience and intelligence about local communities. Strategies such as flexible working, support for returners and carers, and career breaks had been introduced. Concern about pensions was a key influence on nurses\'02 decisions to stay or leave nursing.Conclusions: Efforts were being made to introduce employment strategies to improve the working lives and experiences of all nurses. Some policies designed more specifically for younger nurses requiring childcare were also being taken up by older nurses with caring responsibilities. There were numerous strategies in place or being set up to improve recruitment and retention, indicating a desire amongst managers to retain their pool of nurses.Implications for Nursing Management: Managers should continue to develop policies to retain older nurses and learn from others with successful strategies. [ABSTRACT FROM AUTHOR]

Northern Norrbotten, Sweden is a key part of Baltic Shield and provides a record of magmatic, tectonic and related, superimposed, Fe oxide–apatite and iron oxide–copper–gold (IOCG) mineralization, during the Svecokarelian orogeny. Titanite and allanite from a range of mineral deposits in the area have been analysed for U–Pb isotope systematics and trace element chemistry using laser ablation quadrupole inductively coupled plasma-mass spectrometry (LA-ICP-MS). Analyses of a single sample from the regional scapolite–albite alteration give an age of 1903 ± 8 Ma (2σ) and may be contemporaneous with the early stages of Fe mineralization (1890–1870 Ma). Analyses of titanite and allanite from undeformed IOCG deposits indicate initial alteration at 1862 ± 16 Ma. In many deposits subsequent metamorphic effects reset titanite isotope systematics from 1790 to 1800 Ma, resulting in a spread of U–Pb isotope analyses along concordia. In some instances core regions may record evidence of early thermal events at around 2050 Ma. Titanite and allanite from deformed IOCG deposits on major shear zones record ages from 1785 ± 21 Ma to 1777 ± 20 Ma, corresponding to deformation, metamorphism and secondary hydrothermal alteration as a result of late orogenic movements. The lack of intracrystalline variations in titanite and allanite trace element chemistry suggests that hydrothermal fluid chemistry and metal source were the main controls on mineral trace element chemistry. Titanite from undeformed Fe oxide–apatite and IOCG deposits is typically light rare earth element (LREE) enriched, and shows low U/Th ratios and low Ni in both intermediate to acid and basic volcanic-hosted deposits. This is consistent with a granitic source for metals. Minor variations in trace element patterns are consistent with the influence of aqueous complex formation on relative REE solubility. Deposits related to the Nautanen Deformation Zone have relatively heavy REE (HREE)-enriched titanite, and LREE-depleted allanite, with high U/Th ratios and elevated Ni contents, consistent with leaching of metals from the local basic volcanic rocks. All hydrothermal titanites are high field strength element enriched (Nb, Ta, Zr) indicating their transport as a result of either high salinities or high F contents, or both. The data overall support models of IOCG-type mineralization as a result of regional circulation of saline hydrothermal fluids in association with major crustal structures, with at least some metallic components derived from the granitoid rocks of the area. All the deposits here show evidence of subsequent metamorphism, although penetrative fabrics are restricted to regional-scale deformation zones. [ABSTRACT FROM PUBLISHER]

AIM: This paper is a report of a study conducted to explore strategies for retaining nurses and their implications for the primary and community care nursing workforce. BACKGROUND: An ageing nursing workforce has forced the need for recruitment and retention of nurses to be an important feature of workforce planning in many countries. However, whilst there is a growing awareness of the factors that influence the retention of nurses within secondary care services, little is known about those that influence retention of nurses in primary and community care. Little is known about the age profile of such nurses or the impact of the ageing nursing workforce on individual nursing specialities in the England. METHODS: Nursing databases were analysed to explore the impact of age on nursing specialities in primary and community care. The nurse retention literature was reviewed from 1995 to 2006. FINDINGS: Workforce statistics reveal that primary and community care nurses have a higher age profile than the National Health Service nursing workforce as a whole. However, there are important gaps in the literature in relation to the factors influencing retention of older primary and community care nurses. Specific factors exist for older nurses within primary care that are unique. Implications for their retention are suggested. CONCLUSION: Particular attention needs to be paid to factors influencing retention of older nurses in primary and community care. These factors need to be incorporated into local and national policy planning and development. [ABSTRACT FROM AUTHOR]

Title. Retaining older nurses in primary care and the community. Aim. This paper is a report of a study conducted to examine issues associated with the impact of age on the retention of female primary and community care nurses in the National Health Service in England. Background. Little is known about why older nurses in the primary and community care workforce leave and what might encourage them to stay. Methods. A cross-sectional survey using a semi-structured postal questionnaire was carried out during 2005. Responses were received from 485 (61%) district nurses, health visitors, school nurses and practice nurses in five primary care trusts in England. Data were analysed to test for associations. Results. Older nurses were more likely than younger ones to report that their role had lived up to expectations ( P = 0·001). Issues important for older nurses were feeling valued and being consulted when change was implemented. Important factors encouraging nurses to stay were pension considerations, reduced working hours near retirement, and reduced workload. For those with degree-level qualifications, enhanced pay was a factor encouraging retention ( P = 0·044). Nurses might leave in response to high administrative workloads, problems in combining work and family commitments ( P <= 0·001), and lack of workplace support ( P = 0·029). Retirement and pensions advice was not widely available. Conclusion. Since two-thirds of nurses were generally happy in their role, it is important that the conditions necessary to maintain this level of satisfaction are continued throughout a nurse's working life. Nurses may all too easily consider leaving prematurely unless policy makers and managers ensure that their working environment reflects the issues nurses consider to be conducive to retention. [ABSTRACT FROM AUTHOR]

Single electron charging effects in a surface-gated InSb/AlInSb QW structure are reported. This material, due to its large g-factor and light effective mass, offers considerable advantages over more commonly used materials, such as GaAs, for quantum information processing devices. However, differences in material and device technology result in significant processing challenges. Simple Coulomb blockade and quantized confinement models are considered to explain the observation of conductance oscillations in these structures. The charging energy (e²/C) is found to be comparable with the energy spectrum for single particle states (1E). [ABSTRACT FROM AUTHOR]

Elongate and deformed garnets from Glenelg, NW Scotland, occur within a thin shear zone transecting an eclogite body that has undergone partial retrogression to amphibolite facies at circa 700°C. Optical microscopy, back-scattered electron imaging, electron probe microanalysis and electron back-scatter diffraction reveal garnet sub-structures that are developed as a function of strain. Subgrains with low-angle misorientation boundaries occur at low strain and garnet orientations are dispersed, around rational crystallographic axes, across these boundaries. Towards high-strain areas, boundary misorientations increase and there is a loss of crystallographic control on misorientations, which tend towards random. In high-strain areas, a polygonal garnet microstructure is developed. The garnet orientations are randomly dispersed around the original single-crystal orientation. Some garnet grains are elongate and Ca-rich garnet occurs on the faces of elongate grains oriented normal to the foliation. Commonly, the garnet grains are admixed with matrix minerals, and, where in contact with other phases, garnet is well faceted. We suggest that individual garnet porphyroclasts record an evolution from low-strain conditions, where dislocation creep and recovery accommodated deformation, through increasing strain, where dynamic recrystallization occurred by subgrain rotation, to highest strains, where recrystallized grains were able to deform by diffusion creep assisted grain boundary sliding with associated rotations. [ABSTRACT FROM AUTHOR]

Peak and retrograde P--T conditions of Grenville-age eclogites from the Glenelg--Attadale Inlier of the northwest Highlands of Scotland are presented. Peak conditions are estimated as c. 20 kbar and 750-780 °C, in broad agreement with previous work. The eclogites subsequently followed a steep decompression path to c. 13 kbar and 650-700 °C during amphibolite facies retrogression. Peak eclogite facies metamorphism occurred > 1080 Ma and retrogression at c. 995 Ma, suggesting fairly sluggish uplift rates of < 0.3 km/Ma and cooling rates of < 1.25 °C/Ma, when compared with other parts of the Grenville orogeny and/or modern orogens, However, current poor constraints on the timing of peak metamorphism mean that these rates cannot be used to interpret the geodynamic evolution of this part of the orogen. The P--T--t data, together with petrology and the field relationships between the basement rocks of the Glenelg--Attadale Inlier and the overlying Moine Supergroup, mean that it is difficult to support the currently held view that an unconformable relationship exists between the two. It is suggested that more data are required in order to re-interpret the Neoproterozic tectonic evolution of the northwest Highlands of Scotland. [ABSTRACT FROM AUTHOR]

The effects of fluorine on the hot-carrier induced degradation in low-thermal-budget polysilicon-emitter NPN bipolar transistors have been examined. Forward Gummel plots, base-emitter (BE) diode characteristics, and stress currents were measured during reverse BE bias stress. Fluorinated devices behave similarly under stress to nonfluorinated devices retaining the initial improvement observed in the forward-bias base current, which is due to suppression of recombination in the BE junction depletion regions at the oxide/silicon interface. The benefits of fluorination, and particularly the reduction in base current in fluorinated devices, appear to be robust—that is, there is no evidence that the defects passivated by fluorine are reactivated during stressing, or that fluorination introduces additional defects that are activated under stressing. [ABSTRACT FROM AUTHOR]

We propose a set of standards to aid the physician in the care of older patients. These standards are based on the practical experiences of our own group and of others with years of clinical practice in geriatric medicine. The standards also reflect the guidelines, position papers, and deliberations of various organizations concerned with the care of older people. This article does not discuss specific illnesses or the common geriatric syndromes. The proposed standards cover comprehensive care and assessment, especially of vulnerable elders and prevention of disease and disability. We also propose standards for facilitation of care across the health service continuum, care of the nursing home resident, and palliative and hospice care. [ABSTRACT FROM AUTHOR]

AIMS--To determine whether oro-pharyngeal colonisation by Chlamydia trachomatis occurs in patients at risk of genital chlamydia infection; to determine whether screening pharyngeal specimens by polymerase chain reaction (PCR) increases detection of C trachomatis compared with isolation and the immune dot blot test; and to correlate the detection of C trachomatis and Neisseria gonorrhoeae in the pharynx with a history of oro-genital contact. METHODS--Thirteen homosexuals and 11 heterosexuals were included in the study. Urogenital and pharyngeal specimens were tested for C trachomatis and N gonorrhoeae using standard clinical diagnostic procedures. Two different PCR methodologies were also used to detect C trachomatis in the pharyngeal specimens. Results were correlated with the mode of sexual practice. RESULTS--Oro-genital sexual contact was practised by 64.9% (72/111) of heterosexuals in addition to penetrative penovaginal intercourse. Additionally, 62.1% (77/124) of all patients did not use any form of barrier protection. Of those who admitted to oro-genital sexual contact, 17.6% of patients with a genital chlamydial infection and 36.4% of those with genital gonorrhoea also had asymptomatic pharyngeal colonisation. C trachomatis was detected in three of 124 (2.4%) pharyngeal specimens by PCR which were reported as negative by chlamydial culture; one was positive by the immune dot blot test. CONCLUSION--The majority of patients practised unprotected oro-genital contact and significant pharyngeal colonisation by C trachomatis and N gonorrhoeae occurred if genital infection was present. Despite the use of PCR in a population at high risk of sexually transmitted disease, the prevalence of chlamydia in the pharynx was very low. This indicates that transmission of C trachomatis to the oro-pharynx does not pose a serious health risk and that screening of patients for oro-pharyngeal C trachomatis is not worthwhile. [ABSTRACT FROM PUBLISHER]

An aspiration based simulated annealing algorithm for continuousvariables has been proposed. The new algorithm is similar to the one givenby Dekkers and Aarts (1991) except that a kind of memory is introduced intothe procedure with a self-regulatory mechanism. The algorithm has beenapplied to a set of standard global optimization problems and a number ofmore difficult, complex, practical problems and its performance comparedwith that of the algorithm of Dekkers and Aarts (1991). The new algorithmappears to offer a useful alternative to some of the currently availablestochastic algorithms for global optimization. [ABSTRACT FROM AUTHOR]

We describe global optimization problems from three different fields representing many-body potentials in physical chemistry, optimal control of a chemical reactor, and fitting a statistical model to empirical data. Historical background for each of the problems as well as the practical significance of the first two are given. The problems are solved by using eight recently developed stochastic global optimization algorithms representing controlled random search (4 algorithms), simulated annealing (2 algorithms), and clustering (2 algorithms). The results are discussed, and the importance of global optimization in each respective field is focused. [ABSTRACT FROM AUTHOR]

Depletion of high-energy phosphates, accumulation of inorganic phosphate and intracellular acidosis have each been proposed as important events in the transition from reversible to irreversible ischemic injury. To assess whether each variable is predictive of functional recovery on reperfusion, these were measured in the isolated isovolumic rat heart usingP NMR. Perfused hearts were subjected to either 10, 12 or 40 min of normothermic ischemia followed by 40 min of reperfusion. Hearts were then freeze-clamped for further analysis of phosphate metabolites by NMR and ion chromatography. High-energy phosphates, P, phosphomonoesters and pH were measured byP NMR spectroscopy at 2 minute intervals. Heart rate and developed pressure were monitored simultaneously. All hearts undergoing 10 min of ischemia and 40% of hearts subjected to 12 min of ischemia demonstrated good functional recovery. The remainder of hearts ischemic for 12 min went into contracture on reperfusion with little return of function. Hearts subject to 40 min of ischemia went into ischemic contracture and showed no recovery on reperfusion. Intracellular pH, [ATP], and [P] measured prior to reperfusion did not predict the extent of recovery. However, phosphomonoesters were detected prior to reperfusion in all hearts that did not recover well, but were not observed in hearts that showed good mechanical recovery. Analysis of tissue extracts byP NMR and ion chromatography indicated that the most prominent components of the phosphomonoesters were glucose 6-phosphate, α-glycerol phosphate and AMP. In conclusion, of the various phosphorus metabolites that can be measured byP NMR, only one group, the phosphomonoesters, was predictive of functional recovery. [ABSTRACT FROM AUTHOR]