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A recent review paper on nepheline solid solutions dealt mainly with sodic varieties from nepheline syenites and differentiated alkali basaltic sills. Excel spreadsheets were provided for recalculating cell formulae in terms of the stoichiometric parameters ΔAlcavity cation charge and ΔTframework charge and molecular percentages of the end-members Ne, Ks, Ca-nepheline and excess Si (Qxs). Small amounts of tetrahedral divalent species (usually <0.10 wt.% though with up to 0.33 wt.% MgO) were related to a stuffed-tridymite end-member of ideal formula K8Mg4Si12O32 (denoted KsT2+-nepheline), although the equations used to calculate these end-members only considered Si, Al and Fe3+ as tetrahedral framework species. Recently, K-rich nepheline and kalsilite which contain up 0.54 wt.% MgO have been found in some feldspar-free mafic potassic volcanic rocks from central Brazil. Equations have been developed to deal rigorously with the presence of significant amounts of Mg (and Mn) in recalculating nepheline solid-solution parameters. In two related communications reworked spreadsheets are provided with examples of their use. High quality microprobe analyses of nepheline and kalsilite from magmatic rocks must include analyses for Mg and Mn and, if possible, estimates of Fe2+ contents.
Natural nepheline usually contains very small amounts of MgO (<0.1 wt.%), although these examples are mainly from Mg-poor alkaline igneous rocks such as nepheline syenites. However, this work shows that nepheline and kalsilite with much higher MgO concentrations can occur in the groundmass of strongly SiO2-undersaturated, feldspar-free, mafic volcanic rocks (i.e. olivine-rich foidites). Furthermore, a strong positive correlation is evident between their Mg and Fe contents. The occurrence of Mg-rich nepheline and kalsilite seems to be related to their derivation from Mg-rich magmas when compared to most of the host rocks investigated to date. Additionally, the physicochemical conditions of crystallisation seem to have an important role in the incorporation of ‘small’ divalent cations by these minerals. The prevalence of Mg-rich nepheline and kalsilite as late magmatic phases and the divergent Mg and Fe relationships for phenocrysts and ‘quenched’ groundmass crystals support this hypothesis. The positive correlation between Mg and Fe contents reflects their strong geochemical affinity and the entrance of Fe3+, Fe2+ and Mg2+ cations into the same crystallographic site of nepheline and kalsilite structures. The calculation of atomic formulae and stoichiometry parameters for nepheline-group minerals where data for the T2+ cations (e.g. Mg2+) are incorporated gives more reliable compositional parameters (see Paper 1). Calculated excess silica values (Si′) are affected significantly when the coupled substitution 2Al3+ = Mg2+ + Si4+ is considered. Thus, specific analyses of ‘small’ divalent cations are essential to obtain more realistic values of excess Si′, in particular, for nepheline and kalsilite that crystallised from Mg-rich, Si-poor, mafic–ultramafic alkaline lavas.
The COVID-19 pandemic has disrupted lives and livelihoods, and people already experiencing mental ill health may have been especially vulnerable.
Quantify mental health inequalities in disruptions to healthcare, economic activity and housing.
We examined data from 59 482 participants in 12 UK longitudinal studies with data collected before and during the COVID-19 pandemic. Within each study, we estimated the association between psychological distress assessed pre-pandemic and disruptions since the start of the pandemic to healthcare (medication access, procedures or appointments), economic activity (employment, income or working hours) and housing (change of address or household composition). Estimates were pooled across studies.
Across the analysed data-sets, 28% to 77% of participants experienced at least one disruption, with 2.3–33.2% experiencing disruptions in two or more domains. We found 1 s.d. higher pre-pandemic psychological distress was associated with (a) increased odds of any healthcare disruptions (odds ratio (OR) 1.30, 95% CI 1.20–1.40), with fully adjusted odds ratios ranging from 1.24 (95% CI 1.09–1.41) for disruption to procedures to 1.33 (95% CI 1.20–1.49) for disruptions to prescriptions or medication access; (b) loss of employment (odds ratio 1.13, 95% CI 1.06–1.21) and income (OR 1.12, 95% CI 1.06 –1.19), and reductions in working hours/furlough (odds ratio 1.05, 95% CI 1.00–1.09) and (c) increased likelihood of experiencing a disruption in at least two domains (OR 1.25, 95% CI 1.18–1.32) or in one domain (OR 1.11, 95% CI 1.07–1.16), relative to no disruption. There were no associations with housing disruptions (OR 1.00, 95% CI 0.97–1.03).
People experiencing psychological distress pre-pandemic were more likely to experience healthcare and economic disruptions, and clusters of disruptions across multiple domains during the pandemic. Failing to address these disruptions risks further widening mental health inequalities.
This consensus statement by the Society for Healthcare Epidemiology of America (SHEA) and the Society for Post-Acute and Long-Term Care Medicine (AMDA), the Association for Professionals in Epidemiology and Infection Control (APIC), the HIV Medicine Association (HIVMA), the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Diseases Society (PIDS), and the Society of Infectious Diseases Pharmacists (SIDP) recommends that coronavirus disease 2019 (COVID-19) vaccination should be a condition of employment for all healthcare personnel in facilities in the United States. Exemptions from this policy apply to those with medical contraindications to all COVID-19 vaccines available in the United States and other exemptions as specified by federal or state law. The consensus statement also supports COVID-19 vaccination of nonemployees functioning at a healthcare facility (eg, students, contract workers, volunteers, etc).
HIV-associated neurocognitive disorders (HANDs) are prevalent in older people living with HIV (PLWH) worldwide. HAND prevalence and incidence studies of the newly emergent population of combination antiretroviral therapy (cART)-treated older PLWH in sub-Saharan Africa are currently lacking. We aimed to estimate HAND prevalence and incidence using robust measures in stable, cART-treated older adults under long-term follow-up in Tanzania and report cognitive comorbidities.
A systematic sample of consenting HIV-positive adults aged ≥50 years attending routine clinical care at an HIV Care and Treatment Centre during March–May 2016 and followed up March–May 2017.
HAND by consensus panel Frascati criteria based on detailed locally normed low-literacy neuropsychological battery, structured neuropsychiatric clinical assessment, and collateral history. Demographic and etiological factors by self-report and clinical records.
In this cohort (n = 253, 72.3% female, median age 57), HAND prevalence was 47.0% (95% CI 40.9–53.2, n = 119) despite well-managed HIV disease (Mn CD4 516 (98-1719), 95.5% on cART). Of these, 64 (25.3%) were asymptomatic neurocognitive impairment, 46 (18.2%) mild neurocognitive disorder, and 9 (3.6%) HIV-associated dementia. One-year incidence was high (37.2%, 95% CI 25.9 to 51.8), but some reversibility (17.6%, 95% CI 10.0–28.6 n = 16) was observed.
HAND appear highly prevalent in older PLWH in this setting, where demographic profile differs markedly to high-income cohorts, and comorbidities are frequent. Incidence and reversibility also appear high. Future studies should focus on etiologies and potentially reversible factors in this setting.
Availability of trained professionals to assist researchers navigating regulatory pathways for new drug and device development is limited within academic institutions. We created ReGARDD (Regulatory Guidance for Academic Research of Drugs and Devices), a regional forum initially involving regulatory professionals from four Clinical and Translational Science Award (CTSA)-funded institutions, to build and capitalize on local expertise and to develop a regulatory guidance website geared toward academic researchers. Since 2015, members organized 15 forums covering topics such as FDA premarket submissions, gene therapy, and intellectual property for devices and therapeutics. Through user feedback, targeted surveys, and ongoing iterative processes, we refined and maintained a shared regulatory website, which reached 6000+ users in 2019. Website updates improved navigation to drug versus device topic areas, provided new educational content and videos to address commonly asked questions, and created a portal for posting upcoming training opportunities. Survey respondents rated the website favorably and endorsed expanding ReGARDD as a centralized resource. ReGARDD strengthened the regional regulatory workforce, increased regulatory efficiency, and promulgated best organizational and operational practices. Broad-scale deployment of the ReGARDD model across the CTSA consortium may facilitate the creation of a network of regional forums and reduce gaps in access to regulatory support.
Molecular formulae used to recalculate nepheline analyses generally have different numbers of oxygens (e.g. NaAlSiO4 (Ne), KAlSiO4, (Ks), CaAl2Si2O8 (An) and SiO2 (Q)). A 32 oxygen cell has 16 T cations and 8 cavity sites, but ideal nepheline stoichiometry is not necessarily followed. Ca end-member □CaCaAl2Si2O4 (CaNe) and excess silica end-member □SiSi2O4 (Q’) calculation requires inclusion of both vacancy species as cavity cation values. Q’ parameter calculations can involve different assumptions and four parameters are described: Qxs; QSi; Q(Si–Al); and Qcavity; these should have closely similar values for high-quality, stoichiometric analyses.
Representative published compositions are recalculated to assess whether authors followed ideal nepheline stoichiometry. Phenocrysts from peralkaline rocks and nephelinites typically exhibit Al deficiencies reflected in negative Δ(Al – cavity cation) parameters (ΔAlcc), negative ‘normative’ corundum (Al2O3, Cn), and anomalously low or negative Qxs parameters; for such rock types Q(Si–Al) provides a better estimate of excess silica contents. A ΔT-site (cation charge) parameter (ΔTcharge), is closely coupled to ΔAlcc and end-member NaAlSiO4 has a ΔAlcc/ΔTcharge ratio of 1.4296; the derivation of this value is controlled by strict stuffed-tridymite, unit-cell constraints. Natural nephelines all contain excess silica with a mean ΔAlcc/ΔTcharge of ~1.134 reflecting their Si/Al ratio being > 1.
Nepheline analyses with relatively low Al and Si and high Na (also Ca) contents are common; this might reflect the presence of small amounts (up to ~5%) of cancrinite as an alteration phase or perhaps even in solid solution. The compositions of alteration lamellae of Ca-rich cancrinite in altered nepheline phenocrysts in phonolites from the Marangudzi alkaline complex, Zimbabwe, are used to define diagnostic parameters for recognising such non-stoichiometry. These alteration lamellae formed hydrothermally from Ca-rich and K-poor fluids.
An EXCEL file is provided to help researchers to standardise calculation of nepheline end-member molecular proportions.
Although recent studies have found that there is significant association between anticholinergic and cognitive impairment, especially in the elderly population, there seems to be minimal emphasis on anticholinergic burden (ACB) when prescribing medications to the inpatient psychogeriatric population.
To evaluate the prescribing patterns in Older Person Mental Health Inpatient Unit (OPMHU), whether the ACB Score on admission has been reviewed for lowest possible ACB while maintaining therapeutic effects. A protocol will be developed to ensure that ACB is reviewed for future admissions and discharges.
Fifty patients admitted and discharged from OPMHU are recruited retrospectively from 30th September 2015, excluding outliers and deceased patients. For those who had multiple admissions during that period, only the most recent admission would be included for evaluation. Individual ACB score is calculated on admission and discharge based on pharmacist final medication summary. Their mental health records are also audited for any documented ACB review by the treating team, while making note for any pre-existing cognitive impairment.
ACB has not been taken into consideration in all patients by the treating team on admission as well as when prescribing medications on discharge. Hence, it is unsurprising that the ACB score showed an increment of 30% on discharge (3.25) when compared to the admission score (2.5).
The study found that although ACB poses significant risks on cognitive impairment, this knowledge has not been employed pragmatically. A protocol should be developed to ensure that ACB is evaluated and managed accordingly.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Healthcare personnel (HCP) were recruited to provide serum samples, which were tested for antibodies against Ebola or Lassa virus to evaluate for asymptomatic seroconversion.
From 2014 to 2016, 4 patients with Ebola virus disease (EVD) and 1 patient with Lassa fever (LF) were treated in the Serious Communicable Diseases Unit (SCDU) at Emory University Hospital. Strict infection control and clinical biosafety practices were implemented to prevent nosocomial transmission of EVD or LF to HCP.
All personnel who entered the SCDU who were required to measure their temperatures and complete a symptom questionnaire twice daily were eligible.
No employee developed symptomatic EVD or LF. EVD and LF antibody studies were performed on sera samples from 42 HCP. The 6 participants who had received investigational vaccination with a chimpanzee adenovirus type 3 vectored Ebola glycoprotein vaccine had high antibody titers to Ebola glycoprotein, but none had a response to Ebola nucleoprotein or VP40, or a response to LF antigens.
Patients infected with filoviruses and arenaviruses can be managed successfully without causing occupation-related symptomatic or asymptomatic infections. Meticulous attention to infection control and clinical biosafety practices by highly motivated, trained staff is critical to the safe care of patients with an infection from a special pathogen.
To compare federally reimbursable school meals served when competitive foods are removed and when marketing and nudging strategies are used in school cafeterias operating the National School Lunch Program (NSLP). The second objective was to determine how marketing and nudging strategies influence competitive food sales.
In the Healthy Choices School, all competitive foods were removed; the Healthy Nudging School retained competitive foods and promoted the school meal programme using marketing and nudging strategies; a third school made no changes. Cafeteria register data were collected from the beginning of the 2013–2014 school year through the four-week intervention. Outcome measures included daily entrées served; share of entrées served with vegetables, fruit and milk; and total competitive food sales. Difference-in-difference models were used to examine outcome measure changes.
Three high schools in a diverse, Northeast US urban district with universally free meals.
High-school students participating in the NSLP.
During the intervention weeks, the average number of entrées served daily was significantly higher in the Healthy Choices School (82·1 (se 33·9)) and the Healthy Nudging School (107·4 (se 28·2)) compared with the control school. The only significant change in meal component selection was a 6 % (se 0·02) higher rate of vegetable servings in the Healthy Choices School compared with the control school. Healthy Nudging School competitive food sales did not change.
Both strategies – removing competitive foods and marketing and nudging – may increase school meal participation. There was no evidence that promoting school meals decreased competitive food sales.