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Background: Relatively little information is available regarding the use of psychiatric services by individuals with intellectual disability (ID) in Arab countries. The current study aimed to identify (1) the reasons for referral; (2) demographic characteristics of individuals referred; (3) previous contact with child psychiatric services; (4) psychiatric diagnoses; (5) level of ID; (6) nature of interventions; and (7) patterns of medication usage in individuals attending a specialist psychiatric service for individuals with an ID in the Kingdom of Bahrain. Method: Case file analysis was used. Files that recorded attendance at the specialist service within a specific calendar year were selected. A total of 537 files were available for review and 79 contained records indicating the individual had been seen within the year. Results: The primary referral reason to adult psychiatric services was the presence of behavioural disturbance. Pharmacological intervention was the dominant treatment choice and no individual was recommended for psychological/behavioural intervention. Psychiatric diagnosis was not recorded in over 90% of cases. Conclusion: Services in the Kingdom of Bahrain for individuals with ID rely exclusively on pharmacological approaches for the treatment of behavioural disorders. Implications for best practice guidelines are discussed.

Person Focused Training is introduced as a model of service delivery for people with severe challenging behaviours. It is defined as training and supporting staff to conduct functional assessments and to design and implement positive behavioural support for specific individuals with challenging behaviours. Longitudinal outcome data are presented from 138 behaviour support plans developed by staff over a seven year period were analysed to determine reductions in frequency of challenging behaviours. Degree of behaviour change was determined across topography of behaviour, gender, age, level of disability, location of residence and role of course participant. Results indicate that the implementation by staff of behaviour support plans are associated with significant improvement in 77% of cases at an average follow-up of 22 months after implementation of support plans. Only location of residence was identified as related to reduction in challenging behaviours with large residential centres being associated with lower rates of behavioural improvement. It is argued that Person Focused training may represent an alternative to existing models of supporting individuals with challenging behaviours. The implications of front-line staff designing and implementing behaviour support plans for the organisation of services and the role of the clinical psychologist are considered.

Background: Staff with varying backgrounds and educational qualifications can be effectively trained to implement procedures in line with evidence‐based practice. Behavioural skills training (BST) is a competency‐based training model used to effectively educate a broad selection of professionals, including front line staff, in a range of work‐related skills. However, BST has yet to be evaluated in a large group‐based experiment. Methods: This study involved a parallel cluster randomised control trial. Six service sites, with a total of 54 participants, were randomised to the intervention condition using the 'coin toss' method. The intervention condition used BST to coach intellectual disability staff in reinforcement, systematic prompting, functional communication training and task analysis. Six service sites, with a total of 50 participants, were also randomised to a control condition in which generalised training in behavioural interventions was restricted. Recruited service sites were randomly assigned to the intervention condition (N = 6, n = 54) or the control condition (N = 6, n = 50) at one point in time, immediately after recruitment and before baseline testing took place. Allocations were stratified by service type (residential or day) and geographical region. One member of the research team allocated service sites using the 'coin toss' method, and another member, blind to the allocations, decided which experimental arm would receive the intervention and which would be designated as control. It was not possible to mask the intervention from participants, but they were recruited prior to randomisation. Results: Participants in the intervention condition demonstrated statistically significant improvements in their knowledge scores over the study period. Participants in the control condition showed no change or a statistically significant decrease in their knowledge scores. No statistically significant changes to well‐being were observed for either group. There was clear evidence of knowledge maintenance, as well as skill acquisition and subsequent generalisation to the workplace environment, among participants in the intervention condition. Participants also evaluated the BST intervention positively. Conclusions: Results support BST as a method for disseminating evidence‐based practice to front line staff working with adults with intellectual and developmental disabilities. [ABSTRACT FROM AUTHOR]

Abstract Introduction Throughout the world tuberculosis (TB) is the second leading cause of death due to an infectious agent. The World Health Organization promotes Isoniazid Preventive Therapy (IPT) in children under 5 years who are contacts of persons diagnosed with smear-positive pulmonary TB (SPPTB). In 2019, 33% of children identified as contacts received IPT globally, while in the Americas 11 countries reached coverages ≥ 75%, only 35% did so in the Dominican Republic (DR). The aim of this study was to identify barriers and facilitators for IPT administration in children under 5 in the Area IV Directorate of Health of the DR’s National District. Methods Descriptive study, using mixed methods and sequential explanatory approach. We characterized children under 5 years who were contacts of a person with SPPTB. Later, semi-structured interviews and content analysis allowed identification of barriers and facilitators for IPT administration in children who were contacts of a person diagnosed with SPPTB, as perceived by relatives and health system personnel. Results A total of 238 children were identified as contacts of 174 persons with SPPTB: 36% of these received IPT while no data on IPT administration was found for 11% of them. The proportion of children who had a tuberculin skin test (TST) done was

Tvrdyite, Fe2+Fe3+2Al3(PO4)4(OH)5(OH2)4 2H2O, is a new phosphate mineral from the abandoned Huber open pit, in the Krásno ore district near Horní Slavkov, western Bohemia, Czechia. It was found along with Al-rich beraunite, fluorapatite and pharmacosiderite in a cavity of quartz gangue. Tvrdýite forms acicular to fibrous crystals with diameters in the range 0.5-5 pm and lengths up to 300 pm, partly grouped in radiating aggregates up to 3 mm in size. It has a silvery to olive, greyish green colour with pearly lustre, greyish-white streak and is very brittle with an uneven fracture; individual fibres are somewhat flexible. Cleavage on {100} is good; the Mohs hardness is ~3-4. The calculated density is 2.834 g cm-3. Tvrdýite is optically biaxial (-), with α = 1.650(2), β = 1.671(1) and γ = 1.677(1) (white light); 2V = 56(1)°; dispersion: r > v, strong; optical orientation: Z = b, X ≈ a, Y ≈ c; pleochroism: X= greenish blue, Y= yellowish orange, Z= yellowish orange (X >> Y > Z). Tvrdýite is monoclinic, space group C2/c, a = 20.564(4), b = 5.101(1), c = 18.883(4) Å, β = 93.68(3)° and V = 1976.7(7) Å3, Z = 4, a:b:c = 4.031:1:3.702. The strongest eight lines in the powder X-ray diffraction (XRD) pattern [d in Å (I)(hkl)] are 10.227 (100) (200), 9.400 (6)(002), 7.156 (14) (202̅), 5.120 (7) (400), 3.416 (11) (600), 3.278 (6) (602̅), 2.562 (5) (800) and 2.0511 (3) (1̅0̅,0,0). Chemical analyses by electron microprobe yielded MnO 0.01, ZnO 5.08, FeO 4.31, Fe2O3 21.16, Al2O3 16.71, P2O5 32.64, As2O5 2.56, F 0.53, H2O (calc.) 17.84, O = F -0.22, total 100.62 wt.%. The resulting empirical formula, calculated on the base of 27 anions, obtained from the crystal structure, is Zn0.52Fe2+0.50Fe3+2.21Al2.75(PO4)3.86(AsO4)0.19OH4.60F0.23(OH2)4·2H2O. The ideal formula, Fe2+Fe3+2Al3(PO4)4(OH)5(OH2)4·2H2O, requires FeO 8.75, Fe2O3 19.44, Al2O3 18.62, P2O5 34.56, H2O 18.64, total 100.00 wt.%. The crystal structure of tvrdýite was solved from single-crystal data (synchrotron beamline) and refined to R1 = 0.038 for 2276 reflections with I > 2σ(I). Tvrdýite is isostructural with beraunite, but contains dominant Al in two of the four independent M sites, which are all occupied by Fe in beraunite. [ABSTRACT FROM AUTHOR]

A comparative study is presented of the chemistry and crystallography of zinc-bearing strunzites from Hagendorf Süd, Bavaria, Germany and the Sitio do Castelo mine, Folgosinho, Portugal. Electron microprobe analyses of samples from the two localities show quite different cation substitutions. The Hagendorf Süd mineral is a Zn-bearing ferristrunzite, with compositional zoning due to Zn2+ replacing predominantly Fe3+ as well as minor Mn2+, whereas the Portugese mineral is a Zn-bearing strunzite, in which Zn2+ replaces Mn2+, with minor replacement of Fe3+ by Mn3+. Zincostrunzite, with dominant Zn in the interlayer octahedrally coordinated site, is a new strunzite-group mineral that has been characterized at both locations. Analysis of single-crystal synchrotron data for zinc-bearing ferristrunzite and zincostrunzite crystals from Hagendorf Süd show that the structures of both minerals contain zeolitic water in the interlayer region. The formula for strunzite-group minerals containing the zeolitic water is MFe23+ (PO4)2(OH)2·6.5H2O, M= Fe, Mn, Zn. This formulation agrees with that found for zincostrunzite from the Sitio do Castelo mine, but differs from that reported previously for strunzite, MFe23+ 2 (PO4)2(OH)2·6H2O, which has no interlayer water. Interestingly, the zincostrunzites from the two localities differ in the location of the interlayerwatermolecule, with a corresponding difference in theHbonding. [ABSTRACT FROM AUTHOR]

Wilhelmgümbelite, ideally [ZnFe2+Fe3+3(PO4)3(OH)4(H2O)5]·2H2O, is a new secondary phosphate mineral related closely to schoonerite, [ZnMnFe2+2 Fe3+(PO4)3(OH)2(H2O)7]·2H2O, from oxidized zones of the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Wilhelmgümbelite occurs as radiating sprays of needle-like rectangular laths, up to 0.2 mm long and with colour varying from light yellow brown to orange red. Cleavage is perfect parallel to {010}. The mineral is associated closely with an oxidized pseudomorph of phosphophyllite, recently named steinmetzite. Other associated minerals are albite, apatite, chalcophanite, jahnsite, mitridatite, muscovite and quartz. The calculated density of wilhelmgümbelite is 2.82 g cm-3. It is optically biaxial (+) with α = 1.560(2), β = 1.669(2), γ = 1.718(2), 2V(meas) = 63(1)° and 2V(calc.) = 65°. Dispersion is weak with r > v, orientation X = b, Y = c, Z = a. Pleochroism is weak, with colours Z = orange brown, Y = yellow brown, X = light yellow brown, Z ≫ Y > X. Electron microprobe analyses (average of seven analyses, seven crystals) with H2O and FeO/Fe2O3 calculated on structural grounds, gave FeO 5.8, Fe2O3 25.0, MnO 2.6, ZnO 16.4, P2O5 28.7, H2O 23.4, total 101.9 wt.%. The empirical formula, scaled to 3 P and OH- adjusted for charge balance is Zn1.50Mn2+0.27Fe2+0.60Fe3+2.33(PO4)3·(OH)2.73(H2O)8.27. The structural formula is [Zn(Mn0.27Fe3+0.73)∑1.0 (Zn0.25Fe2+0.15Fe3+0.60)Σ1.0(Zn0.25Fe2+0.45)Σ0.7Fe3+(PO4)3(OH,H2O)9]·2H2O. Wilhelmgümbelite has orthorhombic symmetry, Pmab, Z = 4, with the unit-cell parameters of a = 10.987(7) Å, b = 25.378(13) Å, c = 6.387(6) Å and V = 1781(2) Å3. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(Iobs) (hkl)] 12.65 (100) (020); 8.339 (5) (120); 6.421 (14) (001); 6.228 (8) (011); 4.223 (30) (120) and 2.111 (7) (0 12 0). Wilhelmgümbelite is an oxidized form of schoonerite,with the Mn2+ replaced principally by Fe3+. Its structure differs from that of schoonerite in having the Zn partitioned between two different sites, one five-coordinated as in schoonerite and the other tetrahedrally coordinated. Wilhelmgümbelite also differs structurally from schoonerite in having partial occupation of one of the Fe sites, which appears to be correlated with the Zn partitioning. [ABSTRACT FROM AUTHOR]

Steinmetzite, ideally Zn2Fe3+(PO4)2(OH)·3H2O, is a new mineral from the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Steinmetzite was found in a highly oxidized zone of the Cornelia mine at Hagendorf-Süd. It has formed by alteration of phosphophyllite, involving oxidation of the iron and some replacement of Zn by Fe. Steinmetzite lamellae co-exist with an amorphous Fe-rich phosphate in pseudomorphed phosphophyllite crystals. The lamellae are only a few μm thick and with maximum dimension ~50 μm. The phosphophyllite pseudomorphs have a milky opaque appearance, often with a glazed yellow to orange weathering rind and with lengths ranging from sub-mm to 1 cm. Associated minerals are albite, apatite, chalcophanite, jahnsite, mitridatite, muscovite, quartz and wilhelmgümbelite. Goethite and cryptomelane are also abundant in the oxidized zone. The calculated density is 2.96 g cm-3. Steinmetzite is biaxial (-) with measured refractive indices α = 1.642(2), β = 1.659 (calc.), γ = 1.660(2) (white light). 2V(meas) = 27(1)°; orientation is Y ≈ b, X ^c ≈ 27°, with crystals flattened on {010} and elongated on [001]. Pleochroism shows shades of pale brown; Y > X ≈ Z. Electron microprobe analyses (average of seven crystals) with Fe reported as Fe2O3 and with H2O calculated from the structure gave ZnO 31.1, MnO 1.7, CaO 0.5, Fe2O3 21.9, Al2O3 0.3, P2O5 32.9, H2O 14.1 wt.%, total 102.5%. The empirical formula based on 2 P and 12 O, with all iron as ferric and OH- adjusted for charge balance is Zn1.65Fe3+1.19 Mn2+0.11 Ca0.03Al3+0.02(PO4)2(OH)1.21·2.79H2O. The simplified formula is Zn2Fe3+(PO4)2(OH)·3H2O. Steinmetzite is triclinic, P1̄, with unit-cell parameters: a = 10.438(2), b = 5.102(1), c = 10.546(2) Å, α = 91.37(2), β = 115.93(2) and γ = 94.20(2)°. V = 502.7(3) Å3, Z = 2. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å (I) (hkl)] 9.313(65) (100), 5.077(38) (010), 4.726(47) (002), 4.657(100) (200), 3.365 (55) (3̅02), 3.071(54) (11̄2) and 2.735(48) (3̅1̄2). The structure is related to that of phosphophyllite. [ABSTRACT FROM AUTHOR]

Kummerite, ideally Mn2+Fe3+Al(PO4)2(OH)2 · 8H2O, is a new secondary phosphate mineral belonging to the laueite group, from the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Kummerite occurs as sprays or rounded aggregates of very thin, typically deformed, amber yellow laths. Cleavage is good parallel to {010}. The mineral is associated closely with green Zn- and Al-bearing beraunite needles. Other associated minerals are jahnsite-(CaMnMn) and Al-bearing frondelite. The calculated density of kummerite is 2.34 g cm-3. It is optically biaxial (-), α = 1.565(5), β = 1.600(5) and γ = 1.630(5), with weak dispersion. Pleochroism is weak, with amber yellow tones. Electron microprobe analyses (average of 13 grains) with H2O and FeO/Fe2O3 calculated on structural grounds and normalized to 100%, gave Fe2O3 17.2, FeO 4.8, MnO 5.4, MgO 2.2, ZnO 0.5, Al2O3 9.8, P2O5 27.6, H2O 32.5, total 100 wt.%. The empirical formula, based on 3 metal apfu is (Mn2+0.37Mg0.27Zn0.03Fe2+0.33)∑1.00(Fe3+1.06 Al0.94)∑2.00PO4)1.91(OH)2.27(H2O)7.73. Kummerite is triclinic, P1̅ with the unit-cell parameters of a = 5.316(1) Å, b = 10.620(3) Å, c = 7.118(1) Å, α = 107.33(3)°, β = 111.22(3)°, γ = 72.22(2)° and V = 348.4(2) Å3. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I) (hkl)] 9.885 (100) (010); 6.476 (20) (001); 4.942 (30) (020); 3.988 (9) (1̅10); 3.116 (18) (12̅0); 2.873 (11) (1̅21). Kummerite is isostructural with laueite, but differs in having Al and Fe3+ ordered into alternate octahedral sites in the 7.1 Å trans-connected octahedral chains. [ABSTRACT FROM AUTHOR]

Penberthycroftite, ideally [Al6(AsO4)3(OH)9(H2O)5] · 8Η2O, is a new secondary aluminium arsenate mineral from the Penberthy Croft mine, St. Hilary, Cornwall, England, UK. It occurs as tufts of white, ultrathin (sub-micrometre) rectangular laths, with lateral dimensions generally < 20 μm. The laths are flattened on {010} and elongated on [100]. The mineral is associated with arsenopyrite, bettertonite, bulachite, cassiterite, chalcopyrite, chamosite, goethite, liskeardite, pharmacoalumite-pharmacosiderite and quartz. Penberthycroftite is translucent with a white streak and a vitreous to pearly lustre. The calculated density is 2.18 g/cm3. Optically, only the lower and upper refractive indices could be measured, 1.520(1) and 1.532(1) respectively. No pleochroism was observed. Electron microprobe analyses (average of 14) with H2O obtained from thermogravimetric analysis and analyses normalized to 100% gave Al2O3 = 31.3, Fe2O3 = 0.35, As2O5 = 34.1, SO3 = 2.15 and H2O = 32.1. The empirical formula, based on nine metal atoms and 26 framework anions is [Al5.96Fe0.04(As0.97Al0.03O4)3(SO4)0.26(OH)8.30(H2O)5.44(H2O)7.8, corresponding to the ideal formula [Al6(AsO4)3(OH)9(H2O)5] · 8H2O. Penberthycroftite is monoclinic, space group P21/c with unit-cell dimensions (100 K): a = 7.753(2) Å, b = 24.679(5) Å, c = 15.679(3) Å and β = 94.19(3)°. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I) (hkl)] 13.264(46) (011); 12.402(16)(020); 9.732(100)(021); 7.420(28)(110); 5.6708)(130); 5.423(6)(1̄31). The structure of penberthycroftite was solved using synchrotron single-crystal diffraction data and refined to wRobs = 0.059 for 1639 observed (I > 3σ(I)) reflections. Penberthycroftite has a heteropolyhedral layer structure, with the layers parallel to {010}. The layers are strongly undulating and their stacking produces large channels along [100] that are filled with water molecules. The layers are identical to those in bettertonite, but they are displaced relative to one another along [001] and [010] such that the interlayer volume is decreased markedly (by ~10%) relative to that in bettertonite, with a corresponding reduction in the interlayer water content from 11 H2O per formula unit (pfu) in bettertonite to 8 H2O pfu in penberthycroftite. [ABSTRACT FROM AUTHOR]

Flurlite, ideally Zn3Mn2+Fe3+(PO4)3(OH)2·9H2O, is a new mineral from the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Flurlite occurs as ultrathin (<1 μm) translucent platelets that form characteristic twisted accordion-like aggregates. The colour varies from bright orange red to dark maroon red. Cleavage is perfect parallel to (001). The mineral occurs on mitridatite and is closely associated with plimerite. Other associated minerals are beraunite, schoonerite, parascholzite, robertsite and altered phosphophyllite. The calculated density of flurlite is 2.84 g cm-3. It is optically biaxial (-), α = 1.60(1), β = 1.65(1) and γ = 1.68(1), with weak dispersion and parallel extinction, X ≈c, Y ≈ a, Z ≈ b. Pleochroism is weak, with colours: X = pale yellow, Y = pale orange, Z = orange brown. Electron microprobe analyses (average of seven) with FeO and Fe2O3 apportioned and H2O calculated on structural grounds, gave ZnO 25.4, MnO 5.28, MgO 0.52, FeO 7.40, Fe2O3 10.3, P2O5 27.2, H2O 23.1, total 99.2 wt.%. The empirical formula, based on 3 P a.p.f.u. is Zn2.5Mn2+ 0.6Fe2+ 0.8Mg0.1Fe3+(PO4)3(OH)2·9H2O. Flurlite is monoclinic, P21/m, with the unit-cell parameters (at 100 K) of a = 6.3710(13), b = 11.020(2), c = 13.016(3) Å, β = 99.34 (3)°. The strongest lines in the X-ray powder diffraction pattern are [dobs in Å(I) (hkl)] 12.900(100)(001); 8.375(10)(011); 6.072(14)( 1̅01); 5.567(8)(012); 4.297(21)(003); 2.763(35)(040). Flurlite (R1 = 0.057 for 995 F > 4σ(F)) has a heteropolyhedral layer structure, with layers parallel to (001) and with water molecules packing between the layers. The slab-like layers contain two types of polyhedral chains running parallel to [100]: (a) chains of edge-sharing octahedra containing predominantly Zn and (b) chains in which Fe3+-centred octahedra share their apices with dimers comprising Zn-centred trigonal bipyramids sharing an edge with PO4 tetrahedra. The two types of chains are interconnected by corner-sharing along [010]. A second type of PO4 tetrahedron connects the chains to MnO2(H2O)4 octahedra along [010] to complete the structure of the (001) slabs. Flurlite has the same stoichiometry as schoonerite, but with dominant Zn rather than Fe2+ in the edge-shared chains. Schoonerite has a similar heteropolyhedral layer structure with the same layer dimensions 6.4 × 11.1 Å. The different symmetry (orthorhombic, Pmab) for schoonerite reflects a different topology of the layers. [ABSTRACT FROM AUTHOR]

Bariopharmacoalumite-Q2a2b2c, Ba0.5(Cu,ZnO)0.1H0.6[Al4(OH)4(As0.9Al0.1O4)3]·5.5H2O, from the south mine of the old copper mine at Cap Garonne, France, has a 2 × 2 × 2 I-centred tetragonal superstructure of the basic pharmacosiderite-type structure. Cell parameters are a = 15.405(2) Å and c = 15.553(3) Å . The structure was determined and refined in I4̅2m to R1= 0.057 for 2697 reflections with I > 2σ(I), using synchrotron X-ray data on a twinned crystal. The origin of the superlattice cell doubling was determined to be due predominantly to the ordering of Ba atoms in half of the [0 0 1] channels, centred at (0, 0, 0) and (½, ½, 0). The other channels, centred at (½, 0, 0) and (0, ½, 0), were found to be occupied by corner-connected chains of Cu/Zn-centred square planar units. [ABSTRACT FROM AUTHOR]

Syntheses in acidified hydrothermal (HT) solutions (1 N H2SO4 or stronger) produce monoclinic non-stoichiometric K-jarosites which contain Fe-site vacancies with long-range order. Syntheses in non-acidified HT solutions produce rhombohedral K-jarosites which contain relatively large numbers of Fe-site vacancies with no long-range order. Increasing the [Fe]/[K] ratio, reaction temperature and reaction time in non-acidified solutions promotes the formation of monoclinic jarosites which contain Fe-site vacancies with short-range order. A structural model including details of the ordering of the Fe-site vacancies was obtained by refinement of single-crystal synchrotron data from one of the HT synthesis products; this model was used to refine synchrotron powder X-ray diffraction data from products synthesized at different reaction times, temperatures and [Fe]/[K] ratios. Thermal and chemical analyses are consistent with a model for non-stoichiometry in which domains of stoichiometric jarosite are intergrown with butlerite-like iron-deficient domains with a composition [Fe2(SO4)2(OH)2(H2O)4]. It was found that heterogeneous nucleation of monoclinic jarosite on Si disks is preceded by the formation of an oriented film of Maus's Salt, K5Fe3O(SO4)6·10H2O, as a precursor phase, and that this transforms topotactically into oriented jarosite, which contains butlerite-like layers parallel to the disk surface. Structural models for the transformation of Maus's Salt into jarosite are proposed. [ABSTRACT FROM AUTHOR]

Kleberite, ideally Fe3+Ti6O11(OH)5, is a new mineral (IMA 2012-023) from Tertiary sands at Königshain, Saxony, northeast Germany. It is also found in heavy mineral sands from the Murray Basin, southeast Australia and at Kalimantan, Indonesia. It occurs as rounded anhedral to euhedral translucent grains, 0.04-0.3 mm across, which are generally red-brown, but grade to orange with decreasing iron content. Associated minerals include ilmenite, pseudorutile, 'leucoxene', tourmaline and spinel. The density measured by pycnometry is 3.28 g cm-3, which is lower than the calculated density of 3.91 g cm-3, due to intragrain porosity which is not penetrated by the immersion fluid. The intragrain pores, of median diameter 18 nm, are partially filled with impurity phases including kaolinite, diaspore and quartz. Kleberite grains have a uniaxial (-) character, but localized regions are weakly biaxial (-) with 2V close to zero. The mean refractive index, calculated from reflectance measurements, is 2.16(3). The mean empirical formula from electron-microprobe analyses of 15 Königshain kleberite grains is Fe1.013+Mg0.06Ti6O11.2(OH)4.8[Al0.59Si0.31P0.04O1.60·1.8H2O], where the formula element in square brackets represents impurities in the pores. Kleberite forms over a compositional range with [Ti]/[Fe + Ti] atomic ratios from 0.8-0.9. It has monoclinic symmetry, P21/c, with a = 7.537(1), b = 4.5795(4), c = 9.885(1) Å , β = 131.02(1)º. The six strongest lines in the powder X-ray diffraction (XRD) pattern [listed as d in Å (I)] are as follows: 1.676(100), 2.170(82), 2.466(27), 1.423(22), 3.933(8), 2.764(9). The structure was refined by the Rietveld method on powder XRD data to Rp = 6.3, Rwp = 8.1, RB = 4.0. Kleberite is isostructural with tivanite; their structural formulae are [Ti34+ ⃞][Ti34+ Fe3+]O11(OH)5 and Ti44+ ][V43+]O12(OH)4, respectively. Kleberite has dominant Ti4+ in place of V3+ in the M(2) metal-atom site. The related mineral pseudorutile, [Ti4][(Fe3+,Ti)4](O,OH)16, with Fe3+ > Ti4+ has dominant Fe3+ in this site. Kleberite grains from different localities commonly contain residual MgO-rich ferrian ilmenite. The chemical and physical relationships between the ilmenite and coexisting kleberite are used to evaluate different alteration mechanisms involving selective leaching of divalent oxides from ilmenite and pseudomorphic replacement reactions, respectively. [ABSTRACT FROM AUTHOR]

Lead-bearing phyllotungstite from the Clara mine in the central Black Forest, Germany has a formula (Cs0.41)Na0.14K0.05Pb2.012+Ca0.26[W10.876+Fe3.133+O35.75(OH)6.25](O(H2O)3). X-ray diffraction patterns exhibit pseudohexagonal symmetry, but refinement of single-crystal synchrotron data has shown that the true symmetry is orthorhombic, Cmcm, with a = 7.298(1), b = 12.640(2), c = 19.582(4) Å , and that the pseudohexagonal character is due to submicrometre-scale cyclical twinning by rotation about the pseudohexagonal c axis. The structure can be described in terms of an ordered intergrowth, parallel to (001), of (111)py blocks with pyrochlore-type structures, which are ~6 Å in width, and two-layer wide regions with a hexagonal tungsten bronze (HTB) type structure. Caesium atoms occupy 18-coordinate cavities in the HTB regions, and H2O molecules occupy Φ sites in the A2B2O6Φ pyrochlore blocks. The lowering of symmetry from hexagonal to orthorhombic is due to partial ordering of W and Fe in the octahedral B sites and of Pb and vacancies in the A sites of the pyrochlore blocks. The ideal formula for the intergrowth structure (with no vacancies) is C2A10[B14(O,OH)42]Φ4, where C is the cavity site in the HTB slabs. The mineral has only 21% occupancy of the C site and 25% occupancy of the A site, but full occupancy of the Φ site. There may be some mixing of Cs and H2O between the C and Φ sites. [ABSTRACT FROM AUTHOR]

Ilmenite concentrates from the Murray Basin deposits of southeastern Australia contain discrete grains of chrome spinels as a major impurity that must be removed for the ilmenite to become a satisfactory feedstock for the sulphate route to titania pigment production. Conditions were established for a magnetising roast of the ilmenite samples, followed by a magnetic separation, that produced products with (≤0·1 wt-%Cr2O3. The roasting conditions were adjusted to keep the crystallite size of any rutile formed during the roast to <10 nm. Under these conditions the rutile was appreciably soluble in sulphuric acid so that the roast products had satisfactory digestion properties. The roasting conditions are a sensitive function of the mineralogy of the ilmenite grains resulting from chemical weathering in the deposits. For mildly weathered ilmenite concentrates from the southern Murray Basin, containing intimate fine grained associations of ilmenite and pseudorutile, magnetising roasts at <650°C in slightly reducing fluidising gases gave magnetic products containing, <0·1 wt-%Cr2O3 at >80 wt-% recovery, with high solubilities in sulphuric acid. However, similar conditions were not effective for ilmenite concentrates from the central Murray Basin that contain mixtures of unweathered Mg rich ilmenite and highly weathered ilmenite. The strongly weathered ilmenite contains high levels of intra grain chromia (0·2 wt-%Cr2O3) and generates high levels of rutile on roasting, making it difficult to obtain acceptable sulphate route feedstocks from this ilmenite. [ABSTRACT FROM AUTHOR]

Deals with a study which determined and refined the crystal structure of kassite. Occurrence and chemical composition; Crystallography and crystal structure; Description of structure.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009 [ABSTRACT FROM PUBLISHER]

The impact cratering behavior of polycrystalline ice at a temperature of 259±3 K has been investigated by 16 impacts with 1-mm aluminum 2017 alloy spheres (density 2790 kg m−3) over the velocity range 1 to 7.3 km s−1 using a two-stage light-gas gun. Crater cross-sectional profiles and diameter, depth, and volume data are presented. It is found that there is no significant difference in power-law energy exponents for scaling of crater diameter and volume between these data and previous low-velocity (<1 km s−1) ice impact data. Dimensionless pi group scaling was also found to scale the data in a way which can be readily combined with earlier lower velocity data and data at a lower ice temperature. [Copyright &y& Elsevier]

The structures of Li1+x−yNb1−x−3yTix+4yO3 solid solutions within the so-called M-phase field in the Li2O–Nb2O5–TiO2 system were investigated using high-resolution transmission electron, microscope (HRTEM) and single-crystal X-ray diffraction. The results demonstrated that the phase field is not a solid solution but rather a homologous series of commensurate intergrowth structures with LiNbO3-type (LN) slabs separated by single [Ti2O3]2+ corundum-type layers. The thickness of the LN slab decreases with increasing Ti-content from ∼55 to 3 atomic layers in the metastable H-Li2Ti3O7 end-member. The LN slabs accommodate a wide range of Ti4+/Nb5+ substitution, and for a given homolog the distribution of Ti and Nb is not uniform across the slab. A single-crystal X-ray diffraction study of a structure composed of nine-layer LN slabs revealed preferential segregation of Ti to the slab surfaces which apparently provides partial compensation for the charge on the adjacent [Ti2O3]2+ corundum layers. The extra cations in phases with x>0 are accommodated through the formation of Li-rich Li2MO3-type layers in the middle of the LN slabs. The fraction of layers with extra cations increases with increasing Ti-content in the structure. [Copyright &y& Elsevier]

Despite growing evidence supporting the importance of the quality of attachment during adolescence, no studies have been conducted to date in the Arab world due to an absence of valid and reliable tools to measure this construct in Arabic. The Inventory of Parent and Peer Attachment-Revised (IPPA-R) was devised as a self-report questionnaire in English to assess the quality of adolescent attachment to mother, father, and peers, each scale consisting of 25 items. The current study sets out to determine the psychometric properties of the Arabic IPPA-R and to explore attachment styles in Lebanon in a sample of 765 Lebanese adolescents. Results suggested a modified three-factor structure to reach satisfactory reliability of the Arabic IPPA-R, resulting in a modified questionnaire consisting of 19 items for each of mother (α = .82) and father (α = .85), and 21 items for peers (α = .89). Strict measurement invariance across gender was achieved for the IPPA-R parental forms, while only scalar invariance was achieved for the IPPA-R peers form. Overall, there were significant differences in attachment scores to mother and father, with adolescents scoring higher on attachment to mother, with both scores being significantly lower than attachment to peers. Gender differences were found on the peer scale with girls scoring significantly higher than boys. Results are interpreted from a cultural lens, emphasizing the importance of accounting for cultural, religious, and socio-economic factors in understanding adolescent attachment. This study is the first conducted in the Arab region and provides a road map to understanding gender-roles, parental expectations and adolescent perceived parenting, and their impact on adolescent attachment scores., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Tohme et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)