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Single‐crystalline domains in intergrown microcrystalline material of the new compounds Ba22.5+x La55−x [Si129N240−x O x ]O3:Ce3+ and Ba25.5+x La77−x [Si170N312−x O9+x ]O4:Ce3+ were identified by transmission electron microscopy (TEM). Precise diffraction data from these domains were collected with microfocused synchrotron radiation so that crystal structure elucidation of the complex disordered networks became possible. They are composed of two different interconnected slabs of which one is similar in both compounds, which explains their notorious intergrowth. The distribution of Ba and La is indicated by the analysis of bond‐valence sums and by comparison with isostructural Sr28.5+x La75−x [Si170N312−x O9+x ]O4. Ce3+ doping leads to yellow luminescence. This is a showcase that highlights the discovery and accurate characterization of new compounds relevant for luminescence applications from heterogeneous microcrystalline samples by exploiting the capability of the combination of TEM and diffraction using the latest focusing techniques for synchrotron radiation., Single‐crystalline domains of microcrystalline intergrown oxonitridosilicate oxides Ba22.5+x La55−x [Si129N240−x O x ]O3 and Ba25.5+x La77−x [Si170N312−x O9+x ]O4 and related Sr analogues were identified by TEM. Diffraction data collected with microfocused synchrotron radiation reveal extraordinarily complex tetrahedra networks. This combination of analytical methods enables the characterization of new luminescent materials in heterogeneous powder samples.

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Further examples and discussion of the glasses, meteoritic components, possibly related distal material, and previous interpretations as products of grass fires.

Fluorescent proteins (FPs) feature complex photophysical behavior that must be considered when studying the dynamics of fusion proteins in model systems and live cells. In this work, we characterize mNeonGreen (mNG), a recently introduced FP from the bilaterian Branchiostoma lanceolatum, in comparison to the well-known hydrozoan variants enhanced green fluorescent protein (EGFP) and Aequorea coerulescens GFP by steady-state spectroscopy and fluorescence correlation spectroscopy in solutions of different pH. Blind spectral unmixing of sets of absorption spectra reveals three interconverting electronic states of mNG: a nonfluorescent protonated state, a bright state showing bell-shaped pH dependence, and a similarly bright state dominating at high pH. The gradual population of the acidic form by external protonation is reflected by increased flickering at low pH in fluorescence correlation spectroscopy measurements, albeit with much slower flicker rates and lower amplitudes as compared to Aequorea GFPs. In addition, increased flickering of mNG indicates a second deprotonation step above pH 10 leading to a slight decrease in fluorescence. Thus, mNG is distinguished from Aequorea GFPs by a two-step protonation response with opposite effects that reflects a chemically distinct chromophore environment. Despite the more complex pH dependence, mNG represents a superior FP under a broad range of conditions.

Objective To compare the effect of a conventional to an intensive blood pressure monitoring regimen on blood pressure in hypertensive patients in the general practice setting. Design Randomized controlled parallel group trial with 12-month follow-up. Setting One hundred and ten general practices in all regions of Denmark. Participants One thousand forty-eight patients with essential hypertension. Intervention Conventional blood pressure monitoring ('usual group') continued usual ad hoc blood pressure monitoring by office blood pressure measurements, while intensive blood pressure monitoring ('intensive group') supplemented this with frequent home blood pressure monitoring and 24-hour ambulatory blood pressure monitoring. Primary outcome measures Mean day- and night-time systolic and diastolic 24-hour ambulatory blood pressure. Secondary outcome measures Change in systolic and diastolic office blood pressure and change in cardiovascular risk profile. Results Of the patients, 515 (49%) were allocated to the usual group, and 533 (51%) to the intensive group. The reductions in day- and night-time 24-hour ambulatory blood pressure were similar (usual group: 4.6 ± 13.5/2.8 ± 82 mmHg; intensive group: 5.6 ± 13.0/3.5 ± 8.2 mmHg; P = 0.27/P = 0.20). Cardiovascular risk scores were reduced in both groups at follow-up, but more so in the intensive than in the usual group (P = 0.02). Conclusion An intensive blood pressure monitoring strategy led to a similar blood pressure reduction to conventional monitoring. However, the intensive strategy appeared to improve patients' cardiovascular risk profile through other effects than a reduction of blood pressure. Trial registration Clinical Trials NCT00244660.

In the literature, many seemingly contradictory structure models of boulangerite, ideally Pb5Sb4S11, and the related mineral falkmanite have been reported. These can be explained by a phase transition between a low-temperature (LT) modification (P21/c, a ≈ 8.07 A, b ≈ 23.5 A, c ≈ 21.6 A, β ≈ 100.7°) and a disordered high-temperature (HT) modification [Pnma, a = 23.530(2) A; b = 4.0385(8) A and c = 21.273(2) A, R1(obs) = 0.039] that occurs above ca. 350–400 °C. The almost completely ordered distribution of lead and antimony cations in the LT modification involves a superstructure; the corresponding reflections are obvious in electron and X-ray diffraction patterns. Partial ordering may render them more or less diffuse. They vanish upon heating above the transition temperature, also for originally ordered natural boulangerite (from Trepca, Kosovo), and appear again after annealing below the phase transition temperature (e.g. at 330 °C). The HT phase is characterized by pronounced cation disorder. Cation ordering can be described by group-subgroup relationships which may also serve for a unified description of various structure models from literature. Starting from the orthorhombic HT phase, a translationengleiche followed by an isomorphous symmetry reduction yields the degrees of freedom required for cation ordering. The non-standard setting A21/d11 is optimal for a unified comparison of all known structure models. Varying degrees of ordering reported in literature and observed for various new samples suggest that the transition is kinetically controlled. These relationships also contribute to the long-lasting discussion about the nomenclature of minerals with the sum formula Pb5Sb4S11 or very similar ones. A precise structure determination of a single crystal (grown by chemical vapor transport) using synchrotron radiation along with detailed electron diffraction investigations and high-resolution electron microscopy confirms the statistically disordered structure model of the quenched high-temperature phase. Bond-valence sums (BVS) and interatomic distances confirm the interpretation of cation split positions as the superposition of the corresponding independent cation positions in the LT phase. Measurements of transport properties indicate very low n-type electrical and thermal conductivities for both modifications. The order-disorder transition significantly affects the Seebeck coefficient.

Melam-melem (1:1), an adduct compound that can be obtained from dicyandiamide in autoclave reactions at 450 °C and elevated ammonia pressure, had previously been described based on mass spectrometry and NMR spectroscopy, but only incompletely characterized. The crystal structure of this compound has now been elucidated by means of synchrotron microfocus diffraction and subsequent quantum-chemical structure optimization applying DFT methods. The structure was refined in triclinic space group P 1‾ based on X-ray data. Cell parameters of a=4.56(2), b=19.34(8), c=21.58(11) A, α=73.34(11)°, β=89.1(2)°, and γ=88.4(2)° were experimentally obtained. The resulting cell volumes agree with the DFT optimized value to within 7 %. Molecular units in the structure form stacks that are interconnected by a vast array of hydrogen bridge interactions. Remarkably large melam dihedral angles of 48.4° were found that allow melam to interact with melem molecules from different stack layers, thus forming a 3D network. π-stacking interactions appear to play no major role in this structure.

In South Africa grandparents play a significant role in family life. A qualitative study was undertaken to explore and describe the perspectives of grandparents caring for their grandchildren with substance use disorder (SUD). Data were collected by means of semi-structured interviews with grandmothers and analysed following Tesch’s eight steps. Guba’s classic model was employed for data verification. The findings revealed that grandparents experience heightened levels of stress, fear, intimidation, disappointment, shame and financial constraints, which may subsequently compromise their social wellbeing. Based on these findings, recommendations are made in an attempt to provide solutions to the challenges faced by grandparents.

The (3 + 1)-dimensional modulated crystal structure of the metal-rich cluster compound InMo4O6was solved and refined from single-crystal data in the superspace groupP4/mbm(00γ)00ss[q= 0, 0, 0.1536 (4);a= 9.6664 (9),c= 2.8645 (3) Å;R1(all) = 0.046,wR(all) = 0.076]. The crystal structure is closely related to the NaMo4O6structure type. It is built from rods of Mo6clusters condensedvia transedges. These form channels parallel to [001], in which In6and In7oligomers alternate. Weak diffuse planes parallel to (001)* interconnect the satellite reflections; they occur due to two-dimensional rod disorder of the In oligomer chains.

Non-using siblings are adversely affected by the substance abuse and related behaviour of their brothers and sisters. This article allows greater understanding of the plight of non-using siblings obtained from 28 participants interviewed in this qualitative study. Findings reflect the relationships, feelings, challenges and coping strategies of the participants as well as their perceptions of the role of social workers in assisting the chemical substance abuser. Strategies are suggested for social work policy and practice to treat chemical substance abuse holistically.

The nitridosilicate chloride Ba1.63La7.39Si11N23Cl0.42:Ce3+ was synthesized by metathesis reaction starting from LaCl3, BaH2, CeF3 and the product of the ammonolysis of Si2Cl6. The title compound is stable towards air and moisture. Diffraction data of a microcrystal were recorded using microfocused synchrotron radiation. X-ray spectroscopy confirms the chemical composition of the crystal. IR spectra corroborate absence of N-H bonds. The compound is homeotypic to Ba2Nd7Si11N23 and crystallizes in space group Cmmm with a = 11.009(3), b = 23.243(8), c = 9.706(4) angstrom and Z = 4, R-1(all) = 0.0174. According to bond valence sum calculations, some crystallographic positions show complete occupancy by Ba or La whereas others contain significant amounts of both elements. In contrast to the structure prototype Ba2Nd7Si11N23, Ba1.63La7.39Si11N23Cl0.42:Ce3+ contains chloride ions in channels of the SiN4 tetrahedra network, hinting at various substitution possibilities of the complex zeolite-like structure.

Background The reported high rate of relapse in the context of an ever-increasing rate of substance abuse internationally and in South Africa together with the fact that the topic of sustained recovery from Substance Use Disorder (SUD) appears to be totally neglected in extant literature and research agendas motivated the researchers to conduct this investigation. The aim was to obtain an in-depth understanding of how individuals recovering from a SUD experience and sustain their recovery in order to fill the gap in the knowledge base. Methods A qualitative research approach was followed, employing a narrative and phenomenological research design alongside an explorative, descriptive and contextual strategy of inquiry. Fifteen participants were purposefully recruited; and data were collected by means of individual, face-to-face interviews. Schlossberg’s Transition Process Model (1981) (Schlossberg NK, The Counselling Psychologist 1981;9(2):2-18, Schlossberg NK, Journal of Employment Counselling 2011;48:159-162, Anderson ML et al., Counselling adults in transition: linking Schlossberg’s theory with practice in a diverse world., 2012) served as a theoretical framework and provided the backdrop to, and foundation for, the presentation of the research findings. Results Participants’ entry into recovery was triggered by an internal or external crisis caused by chemical substance abuse. They had to embrace a psychological mind set change, involving commitment to a new way of life in order to sustain their recovery. This, among others, was facilitated by participants’ acceptance of the concept of ‘disease of addiction’ or finding a new faith-based identity. The 12-Step programme and further education and development were found to spiritually support sustained recovery. Strong ongoing support from specialised substance abuse support and/or religious groups, interpersonal relationships with family, spouses and sponsors as well as supportive work environments played a major role in sustaining recovery. The act of helping others further helped the participants to sustain their own recovery. Conclusion Regardless of the pathway of recovery, there are key aspects that appear to aid sustained recovery. In grouping these according to the four S’s in Schlossberg’s Transition Process Model (Schlossberg NK, The Counselling Psychologist 1981;9(2):2-18, Journal of Employment Counselling 2011;48:159-162, Anderson ML et al., Counselling adults in transition: linking Schlossberg’s theory with practice in a diverse world., 2012): self, situation, strategies and support, they seem to facilitate the adaptation to transition from addiction to sobriety. Internal psychological and spiritual resources in terms of self; support (from family, church and support groups); strategies to combat cravings and deal with life problems; and avoiding and managing risk-inducing situations to strengthen recovery.

Greek artists and architects were important social agents who played significant roles in the social, cultural, and economic life of the ancient Greek world. In Artists and Artistic Production in Ancient Greece, art historians, archaeologists, and historians explore the roles and impacts of artists and craftsmen in ancient Greek society. The contributing authors draw upon artistic, architectural, literary, epigraphical, and historical evidence to discuss a range of artists, architects, artistic media, and regions. They refer to historiography and modern theory, taking stock of the past while offering some new directions for future research. Incorporating a variety of methodological approaches and making use of often-neglected evidence, Artists and Artistic Production in Ancient Greece re-examines many long-held ideas and provides a deeper understanding of particular artists and architects, their works, and their social agency.

Three quasi-binary phase systems, BiSX1 − xYx(X,Y= Cl, Br, I; 0 0.32] the BiSCl1 − xIxsystem mimics the behaviour of the BiSCl1 − yBry[BiSBr1 − yIy] system (0

Red single crystals of a hexagonal form of ScAlOC were obtained as a by-product from the synthesis of ScAl 3 C 3 by reacting scandium and carbon in an aluminium melt at 1820 °C. The crystal structure ( hP 8, space group P 6 3 mc , Z = 2, a = 3.24793(3) A, c = 10.1739(1) A, 629 refl., 15 param., R 1 ( F ) = 0.010, w R 2 ( F 2 ) = 0.023) can directly be derived from the binary nitrides AlN and ScN or the oxide carbides Sc(O,C) and Al(O,C), respectively. ScAlOC-II or h -ScAlOC represents a new structure type with simple closest packing of alternating layers of oxygen and carbon. The stacking sequence is ABAC (=(hc) 2 ) with oxygen in a cubic and carbon in a hexagonal sequence. According to the difference in size Sc occupies octahedral voids between every second layer leading to layers of edge-sharing ScO 3 C 3 octahedra. Aluminium is located in half of the tetrahedral voids. The AlOC 3 -tetrahedra are connected to layers by common corners of the carbon atoms. h -ScAlOC continues the row of the rare examples of oxide carbides with ordered anion distribution. Band structure calculations by FP-(L)APW methods revealed that ScAlOC is electron precise with a band gap of 1.2 eV. Calculations of charges by the Bader-method reveal values of Sc +1.87 , Al +2.33 , O −1.52 and C −2.67 . Together with the charge densities and the values of the Laplacian this stands for a mainly ionic bonding containing significant covalent contributions, too. Despite the close similarity to rhombohedral ScAlOC ( r -ScAlOC) there is a striking difference in colour, as r -ScAlOC is black. This is confirmed and explained by the results of the P-DOS, because the lowest states of the conduction band are determined by Sc- d -states. These are significantly lower in r -ScAlOC with ScC 6 and ScO 6 octahedra than in h -ScAlOC leading to a calculated band gap of 0.3 eV.

The nitridosilicate chloride Ba1.63La7.39Si11N23Cl0.42:Ce3+ was synthesized by metathesis reaction starting from LaCl3, BaH2, CeF3 and the product of the ammonolysis of Si2Cl6. The title compound is stable towards air and moisture. Diffraction data of a microcrystal were recorded using microfocused synchrotron radiation. X-ray spectroscopy confirms the chemical composition of the crystal. IR spectra corroborate absence of N-H bonds. The compound is homeotypic to Ba2Nd7Si11N23 and crystallizes in space group Cmmm with a = 11.009(3), b = 23.243(8), c = 9.706(4) angstrom and Z = 4, R-1(all) = 0.0174. According to bond valence sum calculations, some crystallographic positions show complete occupancy by Ba or La whereas others contain significant amounts of both elements. In contrast to the structure prototype Ba2Nd7Si11N23, Ba1.63La7.39Si11N23Cl0.42:Ce3+ contains chloride ions in channels of the SiN4 tetrahedra network, hinting at various substitution possibilities of the complex zeolite-like structure.