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We present a broad study of linear, clustered, noble gas puffs irradiated with the frequency doubled (527 nm) Titan laser at Lawrence Livermore National Laboratory. Pure Ar, Kr, and Xe clustered gas puffs, as well as two mixed-gas puffs consisting of KrAr and XeKrAr gases, make up the targets. Characterization experiments to determine gas-puff density show that varying the experimental parameter gas-delay timing (the delay between gas puff initialization and laser-gas-puff interaction) provides a simple control over the gas-puff density. X-ray emission (>1.4 keV) is studied as a function of gas composition, density, and delay timing. Xe gas puffs produce the strongest peak radiation in the several keV spectral region. The emitted radiation was found to be anisotropic, with smaller X-ray flux observed in the direction perpendicular to both laser beam propagation and polarization directions. The degree of anisotropy is independent of gas target type but increases with photon energy. X-ray spectroscopic measurements estimate plasma parameters and highlight their difference with previous studies. Electron beams with energy in excess of 72 keV are present in the noble gas-puff plasmas and results indicate that Ar plays a key role in their production. A drastic increase in harder X-ray emissions (X-ray flash effect) and multi-MeV electron-beam generation from Xe gas-puff plasma occurred when the laser beam was focused on the front edge of the linear gas puff.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Recently, the telecommunication market experiences an explosion in the subscribers of emergent high-debit services which require bandwidth that exceeds the one provided by actual copper based access networks . To cope with these demands and keep competitive, great efforts have been done to develop access networks based on optical technology, such as passive all-optical networks due to their intrinsic low cost . Sol-gel processing is suitable for the development of organic-inorganic hybrid (OIH) materials for the production of functional integrated optic (IO) devices in a cost effective way. Urea cross-linked OIH show acceptable transparency, mechanical flexibility and thermal stability [3-6]. The control over the refractive index is achieved by zirconium (IV) n-propoxide (ZPO) doping stabilized with methacrylic acid (MA) [3-5]. The combination in a single material of urea cross-linked OIH and ZPO allowed the preparation of UV written low losses planar waveguides  and low rugosity diffraction grating [4,5]. It has been demonstrated that MA acts not only as ZPO stabilizer but impacts directly on the photopolimerization properties as it contains a photopolymerizable group making the OIH easily UV patterned without photoinitiator . Moreover, it also impacts on the OHIs local structure as it forms a complex with ZPO, that originate ordered clusters dispersed within the OIH host [4,5]. Besides the potential of this OIH as IO components, the hybrid hosts are room-temperature efficient white light emitters lacking metal activator ions, presenting quantum yields as higher as 20 % . In this work, a series of OIH, so called di-ureasils, formed of a siliceous skeleton to which oligopolyether chains of different lengths are covalently grafted by means of urea bridges and modified by ZPO and MA will be prepared and characterized by X-ray and small angle X-ray diffractions, Raman, infrared, atomic force and photoluminescence spectroscopies. The use of the proposed OIH in the development of IO functionalities such as optical filters will be evaluated based on waveguide numerical simulation methods (beam propagation method). Waveguides will be written and characterized using the OIH aforementioned. The recording of a Bragg grating in the waveguides allow the implementation of a wavelength discrimination device with applications on optical filtering. The relevant properties of the devices, such as spectral rejection and insertion losses will be characterized.  S-J Park et al. Journal of Lightwave Tech. 22, 2004.  D.J. Shin et al., Journal of Lightwave Tech. 23, 2005.  C. Molina et al., J. Mater. Chem. 15, 3937, 2005.  R.A. Sá Ferreira et al., Proceedings of the International Conference on Telecomunications, 2006.  P.S. André et al. Proceedings ICTON, 1, We.C1.6, 223, 2006.  a) L.D. Carlos et al., Adv. Func. Mater. 11, 111, 2001; b) J. Chem. Phys. B. 108, 14924, 2004. Siemens SA and FCT (POCTI/CTM/59075/2004) is gratefully acknowledged.
Meningococcal carriage dynamics drive patterns of invasive disease. The distribution of carriage by age has been well described in Europe, but not in the African meningitis belt, a region characterised by frequent epidemics of meningitis. We aimed to estimate the age-specific prevalence of meningococcal carriage by season in the African meningitis belt. We searched PubMed, Web of Science, the Cochrane Library and grey literature for papers reporting carriage of Neisseria meningitidis in defined age groups in the African meningitis belt. We used a mixed-effects logistic regression to model meningococcal carriage prevalence as a function of age, adjusting for season, location and year. Carriage prevalence increased from low prevalence in infants (0.595% in the rainy season, 95% CI 0.482–0.852%) to a broad peak at age 10 (1.94%, 95% CI 1.87–2.47%), then decreased in adolescence. The odds of carriage were significantly increased during the dry season (OR 1.5 95% CI 1.4–1.7) and during outbreaks (OR 6.7 95% CI 1.6–29). Meningococcal carriage in the African meningitis belt peaks at a younger age compared to Europe. This is consistent with contact studies in Africa, which show that children 10–14 years have the highest frequency of contacts. Targeting older children in Africa for conjugate vaccination may be effective in reducing meningococcal transmission.
To assess the validity of multivariable models for predicting risk of surgical site infection (SSI) after colorectal surgery based on routinely collected data in national surveillance networks.
Retrospective analysis performed on 3 validation cohorts.
Colorectal surgery patients in Switzerland, France, and England, 2007–2017.
We determined calibration and discrimination (ie, area under the curve, AUC) of the COLA (contamination class, obesity, laparoscopy, American Society of Anesthesiologists [ASA]) multivariable risk model and the National Healthcare Safety Network (NHSN) multivariable risk model in each cohort. A new score was constructed based on multivariable analysis of the Swiss cohort following colorectal surgery, then based on colon and rectal surgery separately.
We included 40,813 patients who had undergone elective or emergency colorectal surgery to validate the COLA score, 45,216 patients to validate the NHSN colon and rectal surgery risk models, and 46,320 patients in the construction of a new predictive model. The COLA score’s predictive ability was poor, with AUC values of 0.64 (95% confidence interval [CI], 0.63–0.65), 0.62 (95% CI, 0.58–0.67), 0.60 (95% CI, 0.58–0.61) in the Swiss, French, and English cohorts, respectively. The NHSN colon-specific model (AUC, 0.61; 95% CI, 0.61–0.62) and the rectal surgery–specific model (AUC, 0.57; 95% CI, 0.53–0.61) showed limited predictive ability. The new predictive score showed poor predictive accuracy for colorectal surgery overall (AUC, 0.65; 95% CI, 0.64–0.66), for colon surgery (AUC, 0.65; 95% CI, 0.65–0.66), and for rectal surgery (AUC, 0.63; 95% CI, 0.60–0.66).
Models based on routinely collected data in SSI surveillance networks poorly predict individual risk of SSI following colorectal surgery. Further models that include other more predictive variables could be developed and validated.
Describe the epidemiological and molecular characteristics of an outbreak of Klebsiella pneumoniae carbapenemase (KPC)–producing organisms and the novel use of a cohorting unit for its control.
A 566-room academic teaching facility in Milwaukee, Wisconsin.
Solid-organ transplant recipients.
Infection control bundles were used throughout the time of observation. All KPC cases were intermittently housed in a cohorting unit with dedicated nurses and nursing aids. The rooms used in the cohorting unit had anterooms where clean supplies and linens were placed. Spread of KPC-producing organisms was determined using rectal surveillance cultures on admission and weekly thereafter among all consecutive patients admitted to the involved units. KPC-positive strains underwent pulsed-field gel electrophoresis and whole-genome sequencing.
A total of 8 KPC cases (5 identified by surveillance) were identified from April 2016 to April 2017. After the index patient, 3 patients acquired KPC-producing organisms despite implementation of an infection control bundle. This prompted the use of a cohorting unit, which immediately halted transmission, and the single remaining KPC case was transferred out of the cohorting unit. However, additional KPC cases were identified within 2 months. Once the cohorting unit was reopened, no additional KPC cases occurred. The KPC-positive species identified during this outbreak included Klebsiella pneumoniae, Enterobacter cloacae complex, and Escherichia coli. blaKPC was identified on at least 2 plasmid backbones.
A complex KPC outbreak involving both clonal and plasmid-mediated dissemination was controlled using weekly surveillances and a cohorting unit.
Improving quality of life (QOL) for people with dementia is a priority. In care homes, we often rely on proxy ratings from staff and family but we do not know if, or how, they differ in care homes.
We compared 1056 pairs of staff and family DEMQOL-Proxy ratings from 86 care homes across England. We explored factors associated with ratings quantitatively using multilevel modelling and, qualitatively, through thematic analysis of 12 staff and 12 relative interviews.
Staff and family ratings were weakly correlated (ρs = 0.35). Median staff scores were higher than family's (104 v. 101; p < 0.001). Family were more likely than staff to rate resident QOL as ‘Poor’ (χ2 = 55.91, p < 0.001). Staff and family rated QOL higher when residents had fewer neuropsychiatric symptoms and severe dementia. Staff rated QOL higher in homes with lower staff:resident ratios and when staff were native English speakers. Family rated QOL higher when the resident had spent longer living in the care home and was a native English. Spouses rated residents’ QOL higher than other relatives. Qualitative results suggest differences arise because staff felt good care provided high QOL but families compared the present to the past. Family judgements centre on loss and are complicated by decisions about care home placement and their understandings of dementia.
Proxy reports differ systematically between staff and family. Reports are influenced by the rater:staff and family may conceptualise QOL differently.
There are no estimates of the heritability of phenotypic udder traits in suckler sheep, which produce meat lambs, and whether these are associated with resilience to mastitis. Mastitis is a common disease which damages the mammary gland and reduces productivity. The aims of this study were to investigate the feasibility of collecting udder phenotypes, their heritability and their association with mastitis in suckler ewes. Udder and teat conformation, teat lesions, intramammary masses (IMM) and litter size were recorded from 10 Texel flocks in Great Britain between 2012 and 2014; 968 records were collected. Pedigree data were obtained from an online pedigree recording system. Univariate quantitative genetic parameters were estimated using animal and sire models. Linear mixed models were used to analyse continuous traits and generalised linear mixed models were used to analyse binary traits. Continuous traits had higher heritabilities than binary with teat placement and teat length heritability (h2) highest at 0.35 (SD 0.04) and 0.42 (SD 0.04), respectively. Udder width, drop and separation heritabilities were lower and varied with udder volume. The heritabilities of IMM and teat lesions (sire model) were 0.18 (SD 0.12) and 0.17 (SD 0.11), respectively. All heritabilities were sufficiently high to be in a selection programme to increase resilience to mastitis in the population of Texel sheep. Further studies are required to investigate genetic relationships between traits and to determine whether udder traits predict IMM, and the potential benefits from including traits in a selection programme to increase resilience to chronic mastitis.
Better indicators of prognosis are needed to personalise post-traumatic stress disorder (PTSD) treatments.
We aimed to evaluate early symptom reduction as a predictor of better outcome and examine predictors of early response.
Patients with PTSD (N = 134) received sertraline or prolonged exposure in a randomised trial. Early response was defined as 20% PTSD symptom reduction by session two and good end-state functioning defined as non-clinical levels of PTSD, depression and anxiety.
Early response rates were similar in prolonged exposure and sertraline (40 and 42%), but in sertraline only, early responders were four times more likely to achieve good end-state functioning at post-treatment (Number Needed to Treat = 1.8, 95% CI 1.28–3.00) and final follow-up (Number Needed to Treat = 3.1, 95% CI 1.68–16.71). Better outcome expectations of sertraline also predicted higher likelihood of early response.
Higher expectancy of sertraline coupled with early response may produce a cascade-like effect for optimal conditions for long-term symptom reduction. Therefore, assessing expectations and providing clear treatment rationales may optimise sertraline effects.
Major depressive disorder (MDD) is a highly heterogeneous condition in terms of symptom presentation and, likely, underlying pathophysiology. Accordingly, it is possible that only certain individuals with MDD are well-suited to antidepressants. A potentially fruitful approach to parsing this heterogeneity is to focus on promising endophenotypes of depression, such as neuroticism, anhedonia, and cognitive control deficits.
Within an 8-week multisite trial of sertraline v. placebo for depressed adults (n = 216), we examined whether the combination of machine learning with a Personalized Advantage Index (PAI) can generate individualized treatment recommendations on the basis of endophenotype profiles coupled with clinical and demographic characteristics.
Five pre-treatment variables moderated treatment response. Higher depression severity and neuroticism, older age, less impairment in cognitive control, and being employed were each associated with better outcomes to sertraline than placebo. Across 1000 iterations of a 10-fold cross-validation, the PAI model predicted that 31% of the sample would exhibit a clinically meaningful advantage [post-treatment Hamilton Rating Scale for Depression (HRSD) difference ⩾3] with sertraline relative to placebo. Although there were no overall outcome differences between treatment groups (d = 0.15), those identified as optimally suited to sertraline at pre-treatment had better week 8 HRSD scores if randomized to sertraline (10.7) than placebo (14.7) (d = 0.58).
A subset of MDD patients optimally suited to sertraline can be identified on the basis of pre-treatment characteristics. This model must be tested prospectively before it can be used to inform treatment selection. However, findings demonstrate the potential to improve individual outcomes through algorithm-guided treatment recommendations.
Brandãoite, [BeAl2(PO4)2(OH)2(H2O)4](H2O), is a new Be–Al phosphate mineral from the João Firmino mine, Pomarolli farm region, Divino das Laranjeiras County, Minas Gerais State, Brazil, where it occurs in an albite pocket with other secondary phosphates, including beryllonite, atencioite and zanazziite, in a granitic pegmatite. It occurs as colourless acicular crystals <10 µm wide and <100 µm long that form compact radiating spherical aggregates up to 1.0–1.5 mm across. It is colourless and transparent in single crystals and white in aggregates, has a white streak and a vitreous lustre, is brittle and has conchoidal fracture. Mohs hardness is 6, and the calculated density is 2.353 g/cm3. Brandãoite is biaxial (+), α = 1.544, β = 1.552 and γ = 1.568, all ± 0.002; 2Vobs = 69.7(10)° and 2Vcalc = 71.2°. No pleochroism was observed. Brandãoite is triclinic, space group P
, a = 6.100(4), b = 8.616(4), c = 10.261(5) Å, α = 93.191(11), β = 95.120(11), γ = 96.863(11)°, V = 532.1(8) Å3 and Z = 2. Chemical analysis of a 4 µm wide needle-shaped crystal by electron microprobe and secondary-ion mass spectrometry gave P2O5 = 28.42, Al2O3 = 20.15, BeO = 4.85, H2O = 21.47 and sum = 74.89 wt.%. The empirical formula, normalised on the basis of 15 anions pfu with (OH) = 2 and (H2O) = 5 apfu (from the crystal structure) is Be0.98Al1.99P2.02H12O15. The crystal structure was solved by direct methods and refined to an R1 index of 7.0%. There are two P sites occupied by P5+, two Al sites occupied by octahedrally coordinated Al3+, and one Be site occupied by tetrahedrally coordinated Be2+. There are fifteen anions, two of which are (OH) groups and five of which are (H2O) groups. The simplified ideal formula is thus [BeAl2(PO4)2(OH)2(H2O)4](H2O) with Z = 2. Beryllium and P tetrahedra share corners to form a four-membered ring. Aluminium octahedra share a common vertex to form an [Al2φ11] dimer, and these dimers are cross-linked by P tetrahedra to form a complex slab of polyhedra parallel to (001). These slabs are cross-linked by BeO2(OH)(H2O) tetrahedra, with interstitial (H2O) groups in channels that extend along .
The depletion of neutral helium atoms has been studied in an unmagnetised spherical plasma created by DC discharge in a multidipole confinement field. Knowing the neutral density profile is critical to predicting the equilibrium flow of such plasmas. A model of the emissivity due to electron-impact excitation of neutral atoms in the plasma has been derived and used to fit radiance measurements of several neutral transitions to extract the radial profile of neutral density for plasmas of varying temperature and density. We report a depletion of the core neutral density varying between negligible levels to 80 % of the edge neutral density depending on the input power and fuelling. The corresponding ionisation fraction varies between 30–80 % in the plasma core. A simple neutral diffusion model is sufficient to describe the shape of neutral density profile implied by the radiance measurements. We have used the measurements to include a drag force due to neutral charge-exchange collisions in simulations of driven plasma flow. The simulation predicts a better fit to Mach probe flow measurements when this neutral drag is accounted for. This work shows that accounting for a realistic neutral profile is important to predict the plasma flow geometry and its magnetohydrodynamics (MHD) stability.
Studies conducted in sub-Saharan Africa suggest a high prevalence of depression and suicidality among adolescents living with HIV (ALWH). This is an important public health issue because depression is known to compromise HIV treatment adherence. However, the drivers of depression and suicidality in this population are unclear. We conducted a cross-sectional study to estimate the associations between internalized stigma, bullying, major depressive disorder, and suicidality.
We conducted a cross-sectional survey between November 2016 and March 2017, enrolling a consecutive sample of 224 ALWH aged 13–17 years. We collected information on demographic characteristics, internalized HIV-related stigma (using the six-item Internalized AIDS-Related Stigma Scale), bullying victimization (using the nine-item Social and Health Assessment Peer Victimization Scale), major depressive disorder [using the Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID)], and suicidality (also using the MINI-KID). We fitted multivariable logistic regression models to estimate the associations between stigma, bullying, major depressive disorder, and suicidality.
Thirty-seven participants (16%) had major depressive disorder, 30 (13%) had suicidality, and nine (4%) had high-risk suicidality. Ninety-one participants (41%) had high levels of internalized stigma, while 97 (43%) reported two or more bullying events in the past year. In multivariable logistic regression models, major depressive disorder had a statistically significant association with bullying (AOR = 1.09; 95% CI 1.00–1.20; p = 0.04); while suicidality (low, moderate, high risk) had statistically significant associations with both bullying (AOR = 1.09; 95% CI 1.01–1.17; p = 0.02) and stigma (AOR = 1.30; 95% CI 1.03–1.30; p = 0.02).
Among ALWH in rural Uganda, stigma and bullying are strongly associated with major depressive disorder and suicidality. There is a need to incorporate psychological interventions in the mainstream HIV care to address these challenges for optimal management of HIV among ALWH.
Arachidonic acid (ARA) and DHA, supplied primarily from the mother, are required for early development of the central nervous system. Thus, variations in maternal ARA or DHA status may modify neurocognitive development. We investigated the relationship between maternal ARA and DHA status in early (11·7 weeks) or late (34·5 weeks) pregnancy on neurocognitive function at the age of 4 years or 6–7 years in 724 mother–child pairs from the Southampton Women’s Survey cohort. Plasma phosphatidylcholine fatty acid composition was measured in early and late pregnancy. ARA concentration in early pregnancy predicted 13 % of the variation in ARA concentration in late pregnancy (β=0·36, P<0·001). DHA concentration in early pregnancy predicted 21 % of the variation in DHA concentration in late pregnancy (β=0·46, P<0·001). Children’s cognitive function at the age of 4 years was assessed by the Wechsler Preschool and Primary Scale of Intelligence and at the age of 6–7 years by the Wechsler Abbreviated Scale of Intelligence. Executive function at the age of 6–7 years was assessed using elements of the Cambridge Neuropsychological Test Automated Battery. Neither DHA nor ARA concentrations in early or late pregnancy were associated significantly with neurocognitive function in children at the age of 4 years or the age of 6–7 years. These findings suggest that ARA and DHA status during pregnancy in the range found in this cohort are unlikely to have major influences on neurocognitive function in healthy children.
J. F. Cooper, NASA Goddard Space Flight Center Greenbelt, Maryland, USA,
R. E. Johnson, University of Virginia Charlottesville, Virginia, USA,
P. Kollmann, Johns Hopkins University Applied Physics Laboratory Laurel, Maryland, USA,
E. Roussos, Max Planck Institute for Solar System Studies Göttingen, GERMANY,
E. C. Sittler, NASA Goddard Space Flight Center Greenbelt, Maryland, USA
Ring systems around magnetized planets are expected to have varied interactions with the magnetic fields, hot plasma, and energetic particles of the associated magnetospheres. In our solar system all the giant planets, Jupiter to Neptune, have magnetospheres with embedded rings. Each ring system and its associated moons have strong interactions with their radiation environments (the most intense of which is at Jupiter). Such interactions both erode diffuse rings (such as the E ring of Saturn) and supply plasma and energetic particles to the magnetosphere and its radiation belts. Compositional and structural measurements of rings are enabled by these interactions, such as the information obtained by detection of the secondary neutron and gamma-ray emissions produced by galactic cosmic ray (GCR) interactions with the rings. It is also notable that Earth has both a magnetosphere with radiation belts, and an artificial ring system of satellites and debris, that continuously interact. Konradi (1988) even projected that the high energy trapped protons of the inner Van Allen Belt should now be experiencing significant depletion by this interaction, and we will later discuss the possible evidence for this. Magnetized exoplanets with rings would have similar interactions.
The ring systems of Jupiter and Saturn have been explored by multiple spacecraft. The Jovian ring environment was first explored in situ in 1974 by Pioneer 11, which subsequently flew under Saturn's main rings in 1979. After passing through the Saturn ring plane near the G ring in 1981, Voyager 2 encountered Uranus in 1986 and then Neptune in 1989, but in neither case were the rings and arcs of these two ice giant planets traversed. The Galileo Probe passed across the Jovian ring in December 1995 en route to the first direct penetration into Jupiter's atmosphere. The Cassini Orbiter crossed over the Saturn A and B rings in mid-2004 (Figure 14.1) as part of the Saturn Orbital Insertion (SOI). Cassini will again traverse the main rings during its Grand Finale orbit phase many times, crossing the ring plane just inwards of the D ring, prior to final atmospheric entry in 2017. With the exception of the Cassini Plasma Spectrometer (CAPS) instrument, turned off in 2012 due to electrical problems, Cassini will continue to operate through the final observations.
The problem of pressure driven infernal type perturbations near the plasma edge is addressed analytically for a circular limited tokamak configuration which presents an edge flattened safety factor. The plasma is separated from a metallic wall, either ideally conducting or resistive, by a vacuum region. The dispersion relation for such types of instabilities is derived and discussed for two classes of equilibrium profiles for pressure and mass density.
Folvikite, Sb5+Mn3+(Mg,Mn2+)10O8(BO3)4, is a new oxyborate mineral from the Kitteln mine, Värmland, Sweden, where it occurs as a primary skarn mineral embedded in calcite. It forms striated prismatic crystals up to 0.3 mm, and is black to dark reddish-brown with submetallic lustre and a reddish-brown streak. It is brittle, has a Mohs hardness of 6, and the calculated density is 4.14 g/cm3. Folvikite is biaxial with indeterminate optic sign due to pervasive twinning. The optic axial angle is 68.9(4)°. Refractive indices were not measured; the calculated mean refractive index is 1.85. Strong pleochroism was observed in plane-polarized light: AB = brown (intermediate), OB = dark brown (maximum) and ON = honey brown (minimum). Folvikite is monoclinic, space group P2, a = 5.3767(10), b = 6.2108(10), c = 10.9389(18) Å, β = 94.399(9)°, V = 364.22(16) Å3 and Z = 1. Chemical analysis by electron microprobe gave Sb2O5 18.15, MgO 24.11, MnO 29.73, Mn2O3 11.62, Al2O3 0.27, Fe2O3 0.45, B2O3 15.27, sum 99.60 wt.%. The B2O3 content was assigned as B = 4 apfu and the Mn2O3 / (MnO + Mn2O3) ratio was determined from the crystal structure. The empirical formula was normalized on the basis of 20 anions pfu: (Sb5+1.02Mn3+1.34Al0.05Fe3+0.05Mg5.46Mn2+3.82□0.26)Σ12O8(BO3)4. A simplified formula may be written as Sb5+Mn3+(Mg,Mn2+)10O8(BO3)4 with Z = 1. The crystal structure was solved by direct methods and refined to an R1 index of 4.1%. Folvikite is a member of the (3 Å) zigzag wallpaper-borate structures in which chains of edge-sharing octahedra extend along the c axis and are cross-linked by BO3 groups. There are five X sites partly occupied by Mn2+ > Mg, one octahedrally coordinated M-site occupied by Sb5+ > Mg, two M sites occupied by Mg ≥ Mn > Sb5+, two M sites occupied by Mn3+ > Mn2+, two M sites occupied by Mg > Mn2+, and one M-site occupied by Mg > □; plus two -coordinated B sites occupied by B. As with the other zigzag borates, the polyhedra are arranged in F-walls, C-walls and S-columns.
The crystal structure of ‘minasgeraisite-(Y)’, triclinic P1, a = 9.994(4), b = 7.705(3), c = 4.764(2) Å, α = 90.042(9), β = 90.218(14), γ = 90.034(9) (°), V = 366.8(5) Å3 and Z = 1, has been refined to an R1 index of 2.86% for 4170 observed (|Fo| > 4σF) reflections. Significant observed (|Fo| > 40–60 σF) reflections violate the presence of a 21-screw axis and an a-glide plane, negating the space group P21/a previously found for minerals of the gadolinite–datolite group. Averaging of the X-ray data in Laue groups 2/m and
gives the following agreement indices: 2/m (9.68%) and
(5.68%). The internal agreement index from averaging of identical reflections collected at multiple positions along the diffraction vector is significantly lower than that for the Laue group
: Rpsi = 2.40%, where 13,109 reflections were collected, 4288 are unique for P1 symmetry, and Rpsi is based on a mean data redundancy factor of > 3. Both the data merging and an |E2–1| value of 0.773 indicate that P1 is the correct space group. The general formula for the gadolinite–datolite group is W2XZ2T2O8V2 (Z = 2) which we have expanded to 20 anions (Z = 1) to show the W-site cation ordering present in ‘minasgeraisite-(Y)’. Bismuth, Ca and REE are ordered over four W sites, with Bi dominant at W1, Ca dominant at W2, and Y dominant at W3 and W4. The dominant constituent at the X sites is a vacancy, and Ca does not occur at the X sites. Significant B and Si are assigned to the Be-dominant Z sites, and the T sites are occupied by Si. The simplified ‘minasgeraisite-(Y)’ formula (Z = 1) is BiCa(Y,Ln)2(□,Mn)2(Be,B,Si)4Si4O16 [(OH),O]4. ‘Minasgeraisite-(Y)’ should be assigned to a triclinic subgroup of the gadolinite–datolite group, and its lower symmetry suggests that Ca-substituted gadolinites and hingganites should be examined for evidence of triclinic symmetry associated with cation order at the W sites.
Introduction: Telephone quitlines are an easily accessible and effective means for delivering cessation services including nicotine replacement therapy (NRT). Varenicline (VAR) may show superior quit rates to NRT, but has not been routinely evaluated in the context of quitlines.
Aims: To assess the feasibility of distributing VAR through a quitline, and preliminarily compare cessation rates between participants receiving VAR and NRT.
Methods: Participants were recruited through the New York State Smokers’ Quitline. Those randomised to VAR (n = 200) were instructed to obtain a prescription from their primary care physician (PCP) to be filled by mail through the research pharmacy. Those randomised to NRT (n = 100) were mailed NRT using an existing protocol. Outcome measures were number of submitted prescriptions and dispensed medication kits, and self-reported 7-day point prevalence abstinence at follow-up.
Results: The research pharmacy filled 100% of prescriptions through the quitline. However, only 27% of the VAR Arm submitted a prescription. An intent-to-treat analysis revealed that those receiving NRT were more likely to be abstinent at follow-up than the VAR Arm (OR, 2.42; 95% CI, 1.27–4.60; p < 0.01). The per-protocol analysis, which only included those in the VAR Arm who submitted a prescription, showed no difference in quit rates.
Conclusions: The present protocol resulted in successful delivery of VAR through the quitline, but a sizable proportion of the VAR Arm did not submit a prescription. Self-reported barriers included being unable to obtain a prescription from a PCP. Future studies should explore alternative methods for delivering VAR through quitlines.
To understand increasing rates of hepatitis C virus (HCV) infection in Tennessee, we conducted testing, risk factor analysis and a nested case–control study among persons who use drugs. During June–October 2016, HCV testing with risk factor assessment was conducted in sexually transmitted disease clinics, family planning clinics and an addiction treatment facility in eastern Tennessee; data were analysed by using multivariable logistic regression. A nested case–control study was conducted to assess drug-using risks and behaviours among persons who reported intranasal or injection drug use (IDU). Of 4753 persons tested, 397 (8.4%) were HCV-antibody positive. HCV infection was significantly associated with a history of both intranasal and IDU (adjusted odds ratio (aOR) 35.4, 95% confidence interval (CI) 24.1–51.9), IDU alone (aOR 52.7, CI 25.3–109.9), intranasal drug use alone (aOR 2.6, CI 1.8–3.9) and incarceration (aOR 2.7, CI 2.0–3.8). By 4 October 2016, 574 persons with a reported history of drug use; 63 (11%) were interviewed further. Of 31 persons who used both intranasal and injection drugs, 26 (84%) reported previous intranasal drug use, occurring 1–18 years (median 5.5 years) before their first IDU. Our findings provide evidence that reported IDU, intranasal drug use and incarceration are independent indicators of risk for past or present HCV infection in the study population.