"It is more isolating to patients if you aren't familiar with the resources": a pilot test of a clinician sensitivity training on eating disorders in pregnancy.

It is more isolating to patients if you aren't familiar with the resources: A pilot test of a clinician sensitivity training on eating disorders in pregnancy.(IRB Number: 1909705198).Background Pregnant women with a history of eating disorders (EDs) or active EDs have greater maternal and child health complications. They are also unlikely to disclose their history with an ED to their clinician, few of which are confident in their knowledge to provide appropriate care for patients who present with EDs. This study's goal was to evaluate changes to knowledge, behavior, and attitudes for health professionals who were part of a sensitivity training (to provide information of and awareness, address potential clinician biases, and offer strategies for more patient-centered care with de-stigmatizing language) about eating disorders and pregnancy compared with those who received a reference document.Methods Our pilot study compared responses of health professionals before and after this sensitivity training (N = 54) with a group who were provided a clinician reference document about the same topic (N = 61).Results Mann-Whitney Wilcoxon tests showed significant differences between the sensitivity training and reference document groups, with the sensitivity training resulting in increases to participants' perception of ED's relevance to overall treatment (p = 0.018), comfort in providing resources (p < 0.0001), frequency of ability to introduce strategies (p = 0.001), and interest in additional strategies/recommendations in treating patients with eating disorders (p = 0.009). Thematic analysis of the open-ended responses indicated four major themes: Resources and support, Treatment, Additional training, and Clinician Strategies. Discussion Results indicated that the sensitivity training improved training outcomes compared to the reference document group. Qualitative responses from both groups indicated four themes that can help inform ED-centered care. This study provides context for future directions for continuing education courses as well as clinical training recommendations for treating pregnant patients with EDs.

Prolactinoma extension as a contributing factor in dopamine agonist-induced CSF rhinorrhea: a systematic review of the literature.

BACKGROUND: Dopamine agonist-induced cerebrospinal fluid (CSF) rhinorrhea is an uncommon treatment-related complication arising in 6.1% of prolactinoma patients treated with dopamine agonists. Locally invasive prolactinomas may create CSF fistulae through formation of dural and osseous skull base defects. Tumor shrinkage secondary to dopamine agonist therapy unmasks skull base defects, thus inducing CSF rhinorrhea. In these cases, repair of the leak may be achieved through collaborative surgical intervention by rhinologists and neurosurgeons. Multiple variables have been investigated as potential contributors to the risk of CSF rhinorrhea development in medically treated prolactinoma patients, with little consensus. OBJECTIVE: The primary aim of our study was the characterization of risk factors for CSF rhinorrhea development following dopamine agonist treatment. METHODS: A systematic review of the literature was conducted to identify cases of CSF rhinorrhea following dopamine agonist treatment of prolactinoma. The clinical history, radiographic findings and treatment outcomes are discussed. RESULTS: Fifty-four patients with dopamine agonist-induced CSF rhinorrhea were identified across 23 articles published from 1979 to 2019. Description of diagnostic imaging [computed tomography (CT)/magnetic resonance imaging (MRI)] was not provided for 18/54 subjects. For the 36 cases that described prolactinoma appearance on CT or MRI, invasion of the cavernous sinuses was reported in 13 (36.1%) and invasion of the sphenoid sinus was reported in 18 (50%). CONCLUSION: Based on our systematic review, we propose that CT findings of osseous erosion of the sella or the anterior skull base may predict dopamine agonist-induced CSF rhinorrhea. We recommend obtaining a thin-slice CT of the sinuses in cases with MRI evidence of sphenoid involvement.

Ultrastructural evidence for presenсe of gap junctions in rare case of pleomorphic xanthoastrocytoma.

The phenomenon of unstable expression of gap junction's proteins connexins remains a "visiting card" of astrocytic tumors with various degrees of malignancy. At the same time, it stays unclear what is detected by the positive expression of connexins in astrocytic tumors: gap junctions, hemi-channels, or connexin proteins in cytosol. In the present work, for the first time, we demonstrate an ultrastructural evidence of gap junctions in pleomorphic xanthoastrocytoma, a rare primary brain tumor, the intercellular characteristics of which are poorly studied and remain very discursive and controversial. The primary tumor mass was resected during craniotomy from a 57-old patient diagnosed with pleomorphic xanthoastrocytoma Grade II based on the histopathological analysis. The immunohistochemical study was conducted with primary antibodies: Neurofilament, Myelin basic protein, Glial fibrillary acidic protein, and Synaptophysin. For electron microscopic examination fragments of tumor tissue were fixed in a glutaraldehyde, postfixed in a 1% OsO4, dehydrated and embedded into resin. After the detailed clinical, histological, and immunohistochemical study we revealed some ultrastructural characteristics of the tumor, as well as the first evidence of direct intercellular connection between the tumor cells via gap junctions. Regularly arranged gap junctions connected the somas of xanthastrocytes with dark cytoplasm containing lipid drops. Besides the localization between the cell bodies, from one to several gap junctions were found between the branches of xanthoastrocytoma in tumor intercellular space in close proximity to tumor cell. Our results may indicate gap junctions as a possible structure for intercellular communication between pleomorphic xanthoastrocytoma cells.

Tachinobia repanda (Hymenoptera: Eulophidae) From Egg Sacs of a Colonial Spider, Cyrtophora moluccensis (Araneae: Araneidae) in Papua New Guinea.

We report the discovery of the wasp Tachinobia repanda Boucek collected from egg sacs of the colonial spider Cyrtophora moluccensis (Doleschall) in Morobe Province, Papua New Guinea (PNG) by Lubin, Y.D. in 1980. This is the first record of T. repanda from egg sacs of a colonial spider. The likely host of this eulophid wasp was the larvae of a sarcophagid fly that parasitizes the egg sacs of these spiders. The 67 T. repanda collected were all females and varied little in body size. We suggest that this species is a gregarious hyperparasitoid.

Sodium percarbonate as a novel intracoronal bleaching agent: assessment of the associated risk of cervical root resorption.

AIM: To evaluate the extraradicular peroxide release from sodium percarbonate compared to sodium perborate as an intracoronal bleaching agent. METHODOLOGY: Sixty mandibular single-rooted premolars with intact CEJ were selected. After root filling, gutta-percha was removed 4 mm apical to CEJ and 2 mm of GIC was condensed over the root filling. Intracoronal bleaching agents were placed into six groups of teeth (n = 10): sodium perborate with distilled water (SPW); sodium percarbonate with distilled water (SPCW); sodium perborate with 30% hydrogen peroxide (SPHP); sodium percarbonate with 30% hydrogen peroxide (SPCHP); 30% hydrogen peroxide as positive control (HP) and distilled water as negative control (CL). The teeth were then mounted in vials filled with distilled water, kept in an incubator and taken out at 1, 3 and 6 days for spectrophotometric analysis. Extraradicular peroxide release was quantified by the ferrothiocyanate method. Statistical analysis was undertaken with one-way anova and Scheffe post hoc tests. RESULTS: The greatest peroxide release occurred in the HP group, followed by the SPCHP and SPHP groups, and then by the SPCW and SPW groups. Intergroup comparison revealed that there was no significant difference in peroxide release among the groups SPCW and SPW on days 1, 3 and 6 (P > 0.05). Similarly, no significant difference was found between the SPCHP and SPHP treated groups on days 1, 3 and 6 (P > 0.05). CONCLUSION: Extraradicular peroxide release from sodium percarbonate was comparable to that of sodium perborate, as the differences were not significant.

Epigenetic mechanisms, T-cell activation, and CCR5 genetics interact to regulate T-cell expression of CCR5, the major HIV-1 coreceptor.

T-cell expression levels of CC chemokine receptor 5 (CCR5) are a critical determinant of HIV/AIDS susceptibility, and manifest wide variations (i) between T-cell subsets and among individuals and (ii) in T-cell activation-induced increases in expression levels. We demonstrate that a unifying mechanism for this variation is differences in constitutive and T-cell activation-induced DNA methylation status of CCR5 cis-regulatory regions (cis-regions). Commencing at an evolutionarily conserved CpG (CpG -41), CCR5 cis-regions manifest lower vs. higher methylation in T cells with higher vs. lower CCR5 levels (memory vs. naïve T cells) and in memory T cells with higher vs. lower CCR5 levels. HIV-related and in vitro induced T-cell activation is associated with demethylation of these cis-regions. CCR5 haplotypes associated with increased vs. decreased gene/surface expression levels and HIV/AIDS susceptibility magnify vs. dampen T-cell activation-associated demethylation. Methylation status of CCR5 intron 2 explains a larger proportion of the variation in CCR5 levels than genotype or T-cell activation. The ancestral, protective CCR5-HHA haplotype bears a polymorphism at CpG -41 that is (i) specific to southern Africa, (ii) abrogates binding of the transcription factor CREB1 to this cis-region, and (iii) exhibits a trend for overrepresentation in persons with reduced susceptibility to HIV and disease progression. Genotypes lacking the CCR5-Δ32 mutation but with hypermethylated cis-regions have CCR5 levels similar to genotypes heterozygous for CCR5-Δ32. In HIV-infected individuals, CCR5 cis-regions remain demethylated, despite restoration of CD4+ counts (≥800 cells per mm(3)) with antiretroviral therapy. Thus, methylation content of CCR5 cis-regions is a central epigenetic determinant of T-cell CCR5 levels, and possibly HIV-related outcomes.

Increased Autolysis of µ-Calpain in Skeletal Muscles of Chronic Alcohol-Fed Rats.

BACKGROUND: Proteolysis can proceed via several distinct pathways such as the lysosomal, calcium-dependent, and ubiquitin-proteasome-dependent pathways. Calpains are the main proteases that cleave a large variety of proteins, including the giant sarcomeric proteins, titin and nebulin. Chronic ethanol feeding for 6 weeks did not affect the activities of µ-calpain and m-calpain in the m. gastrocnemius. In our research, changes in µ-calpain activity were studied in the m. gastrocnemius and m. soleus of chronically alcohol-fed rats after 6 months of alcohol intake. METHODS: SDS-PAGE analysis was applied to detect changes in titin and nebulin contents. Titin phosphorylation analysis was performed using the fluorescent dye Pro-Q Diamond. Western blotting was used to determine µ-calpain autolysis as well as µ-calpain and calpastatin contents. The titin and nebulin mRNA levels were assessed by real-time PCR. RESULTS: The amounts of the autolysed isoform (78 kDa) of full-length µ-calpain (80 kDa) increased in the m. gastrocnemius and m. soleus of alcohol-fed rats. The calpastatin content increased in m. gastrocnemius. Decreased intact titin-1 (T1) and increased T2-proteolytic fragment contents were found in the m. gastrocnemius and m. soleus of the alcohol-fed rats. The nebulin content decreased in the rat gastrocnemius muscle of the alcohol-fed group. The phosphorylation levels of T1 and T2 were increased in the m. gastrocnemius and m. soleus, and decreased titin and nebulin mRNA levels were observed in the m. gastrocnemius. The nebulin mRNA level was increased in the soleus muscle of the alcohol-fed rats. CONCLUSIONS: In summary, our data suggest that prolonged chronic alcohol consumption for 6 months resulted in increased autolysis of µ-calpain in rat skeletal muscles. These changes were accompanied by reduced titin and nebulin contents, titin hyperphosphorylation, and development of hindlimb muscle atrophy in the alcohol-fed rats.

Synthesis, Structural, Thermal, and Electronic Properties of Palmierite-Related Double Molybdate α-Cs2Pb(MoO4)2.

Cs2Pb(MoO4)2 crystals were prepared by crystallization from their own melt, and the crystal structure has been studied in detail. At 296 K, the molybdate crystallizes in the low-temperature α-form and has a monoclinic palmierite-related superstructure (space group C2/m, a = 2.13755(13) nm, b = 1.23123(8) nm, c = 1.68024(10) nm, ß = 115.037(2)°, Z = 16) possessing the largest unit cell volume, 4.0066(4) nm3, among lead-containing palmierites. The compound undergoes a distortive phase transition at 635 K and incongruently melts at 943 K. The electronic structure of α-Cs2Pb(MoO4)2 was explored by using X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy methods. For α-Cs2Pb(MoO4)2, the photoelectron core-level and valence-band spectra and the XES band representing the energy distribution of Mo 4d and O 2p states were recorded. Our results allow one to conclude that the Mo 4d and O 2p states contribute mainly to the central part and at the top of the valence band, respectively, with also significant contributions throughout the whole valence-band region of the molybdate under consideration.

Genetic background contributes to the co-morbidity of anxiety and depression with audiogenic seizure propensity and responses to fluoxetine treatment.

BACKGROUND: Anxiety and depression are the most frequent comorbidities of different types of convulsive and non-convulsive epilepsies. Increased anxiety and depression-like phenotype have been described in the genetic absence epilepsy models as well as in models of limbic epilepsy and acquired seizure models, suggesting a neurobiological connection. However, whether anxiety and/or depression are comorbid to audiogenic epilepsy remains unclear. The aim of this study was to investigate whether anxiety or depression-like behavior can be found in rat strains with different susceptibility to audiogenic seizures (AS) and whether chronic fluoxetine treatment affects this co-morbidity. METHODS: Behavior in the elevated plus-maze and the forced swimming test was studied in four strains: Wistar rats non-susceptible to AS; Krushinsky-Molodkina (KM) strain, selectively bred for AS propensity from outbred Wistar rats; and a selection lines bred for maximal AS expression (strain "4") and for a lack of AS (strain "0") from KM×Wistar F2 hybrids. Effects of chronic antidepressant treatment on AS and behavior were also evaluated. RESULTS: Anxiety and depression levels were higher in KM rats (with AS) compared with Wistar rats (without AS), indicating the comorbidity with AS. However, in strains "4" and "0" with contrasting AS expression, but with a genetic background close to KM rats, anxiety and depression were not as divergent as in KMs versus Wistars. Fluoxetine treatment exerted an antidepressant effect in all rat strains irrespective of its effect on AS. CONCLUSIONS: Genetic background contributes substantively to the co-morbidity of anxiety and depression with AS propensity.

The Promise and Pitfalls of Using Crowdsourcing in Research Prioritization for Back Pain: Cross-Sectional Surveys.

BACKGROUND: The involvement of patients in research better aligns evidence generation to the gaps that patients themselves face when making decisions about health care. However, obtaining patients' perspectives is challenging. Amazon's Mechanical Turk (MTurk) has gained popularity over the past decade as a crowdsourcing platform to reach large numbers of individuals to perform tasks for a small reward for the respondent, at small cost to the investigator. The appropriateness of such crowdsourcing methods in medical research has yet to be clarified. OBJECTIVE: The goals of this study were to (1) understand how those on MTurk who screen positive for back pain prioritize research topics compared with those who screen negative for back pain, and (2) determine the qualitative differences in open-ended comments between groups. METHODS: We conducted cross-sectional surveys on MTurk to assess participants' back pain and allow them to prioritize research topics. We paid respondents US $0.10 to complete the 24-point Roland Morris Disability Questionnaire (RMDQ) to categorize participants as those "with back pain" and those "without back pain," then offered both those with (RMDQ score ≥7) and those without back pain (RMDQ <7) an opportunity to rank their top 5 (of 18) research topics for an additional US $0.75. We compared demographic information and research priorities between the 2 groups and performed qualitative analyses on free-text commentary that participants provided. RESULTS: We conducted 2 screening waves. We first screened 2189 individuals for back pain over 33 days and invited 480 (21.93%) who screened positive to complete the prioritization, of whom 350 (72.9% of eligible) did. We later screened 664 individuals over 7 days and invited 474 (71.4%) without back pain to complete the prioritization, of whom 397 (83.7% of eligible) did. Those with back pain who prioritized were comparable with those without in terms of age, education, marital status, and employment. The group with back pain had a higher proportion of women (234, 67.2% vs 229, 57.8%, P=.02). The groups' rank lists of research priorities were highly correlated: Spearman correlation coefficient was .88 when considering topics ranked in the top 5. The 2 groups agreed on 4 of the top 5 and 9 of the top 10 research priorities. CONCLUSIONS: Crowdsourcing platforms such as MTurk support efforts to efficiently reach large groups of individuals to obtain input on research activities. In the context of back pain, a prevalent and easily understood condition, the rank list of those with back pain was highly correlated with that of those without back pain. However, subtle differences in the content and quality of free-text comments suggest supplemental efforts may be needed to augment the reach of crowdsourcing in obtaining perspectives from patients, especially from specific populations.

Exclusive selectivity in the one-pot formation of C-C and C-Se bonds involving Ni-catalyzed alkyne hydroselenation: optimization of the synthetic procedure and a mechanistic study.

A unique Ni-catalyzed transformation is reported for the one-pot highly selective synthesis of previously unknown monoseleno-substituted 1,3-dienes starting from easily available terminal alkynes and benzeneselenol. The combination of a readily available catalyst precursor, Ni(acac)2, and an appropriately tuned phosphine ligand, PPh2Cy, resulted in the exclusive assembly of the s-gauche diene skeleton via the selective formation of C-C and C-Se bonds. The unusual diene products were stable under regular experimental conditions, and the products maintained the s-gauche geometry both in the solid state and in solution, as confirmed by X-ray analysis and NMR spectroscopy. Thorough mechanistic studies using ESI-MS revealed the key Ni-containing species involved in the reaction.

Responses of zebra and quagga mussels to copper and tribytiltin exposure: Bioconcentration, metabolic and cardiac biomarkers.

One of the top ecological priorities is to find sensitive indicators for pollution monitoring. This study focuses on the bioconcentration and responses (condition index, survival, oxygen consumption, heart rates, and oxidative stress and neurotoxic effect biomarkers) of mussels from the Volga River basin, Dreissena polymorpha and Dreissena bugensis, to long-term exposure to toxic chemicals such as tributyltin (TBT, 25 and 100 ng/L) and copper (Cu, 100 and 1000 µg/L). We found that TBT was present in the tissues of zebra and quagga mussels in comparable amounts, whereas the bioconcentration factor of Cu varied depending on its concentration in water. Differences in responses between the two species were revealed. When exposed to high Cu concentrations or a Cu-TBT mixture, quagga mussels had a lower survival rate and a longer heart rate recovery time than zebra mussels. TBT treatment caused neurotoxicity (decreased acetylcholinesterase activity) and oxidative stress (increased levels of thiobarbituric acid reactive substances) in both species. TBT and Cu levels in mussel tissues correlated positively with the condition index, but correlated with the level of acetylcholinesterase in the mussel gills. The principal component analysis revealed three main components: the first consists of linear combinations of 14 variables reflecting TBT water pollution, TBT and Cu levels in mussel tissues, and biochemical indicators; the second includes Cu water concentration, cardiac tolerance, and mussel size; and the third combines weight, metabolic rate, and heart rates. Quagga mussels are less tolerable to contaminants than zebra mussels, so they may be used as a sensitive indicator.

Coprobacter fastidiosus gen. nov., sp. nov., a novel member of the family Porphyromonadaceae isolated from infant faeces.

A novel obligately anaerobic, non-spore-forming, rod-shaped, non-motile Gram-reaction-negative bacterium was isolated from infant faeces. The strain, designated NSB1(T), was able to grow on rich media at 30-37 °C, in the presence of up to 2 % (w/v) Oxgall and 2 % (w/v) NaCl. Cells of strain NSB1(T) produced catalase, but not urease and indole. Aesculin was not hydrolysed. The strain was able to utilize d-glucose, lactose, maltose, mannose and raffinose as electron donors. When grown on d-glucose, the main metabolic end products were propionic and acetic acids, with a minor product being succinic acid. The major cellular fatty acids, iso-C15 : 0 and anteiso-C15 : 0, were present at a 1 : 1 molar ratio. The major menaquinone was MK-11. The DNA G+C content was found to be 38.5 mol%. According to 16S rRNA gene sequence analysis strain NSB1(T) is a member of the family Porphyromonadaceae, phylum Bacteroidetes. The closest relatives of the strain were Barnesiella viscericola (88.2 % identity) and Barnesiella intestinihominis (87.4 % identity). On the basis of phenotypic and genotypic properties of strain NSB1(T) we conclude that this strain represent a novel species in a new genus within the family of Porphyromonadaceae for which the name Coprobacter fastidiosus gen. nov., sp. nov. is proposed. The type strain of the species is NSB1(T) ( = DSM 26242(T), = VKM B-2743(T)).

Design of plastic diffractive-refractive compact zoom lenses for visible-near-IR spectrum.

The requirements for selecting the initial scheme for a compact plastic zoom lens are formulated. The main stages of the initial scheme of the transformation, incorporating the diffractive lens and replacement of the lenses' glasses by optical plastics, are presented. The efficiency of the suggested techniques of the optical layout process are demonstrated by using the example of the design and analysis of a zoom lens intended for use in security cameras for day or night vision.

Peptaibol antiamoebin I: spatial structure, backbone dynamics, interaction with bicelles and lipid-protein nanodiscs, and pore formation in context of barrel-stave model.

Antiamoebin I (Aam-I) is a membrane-active peptaibol antibiotic isolated from fungal species belonging to the genera Cephalosporium, Emericellopsis, Gliocladium, and Stilbella. In comparison with other 16-amino acid-residue peptaibols, e.g., zervamicin IIB (Zrv-IIB), Aam-I possesses relatively weak biological and channel-forming activities. In MeOH solution, Aam-I demonstrates fast cooperative transitions between right-handed and left-handed helical conformation of the N-terminal (1-8) region. We studied Aam-I spatial structure and backbone dynamics in the membrane-mimicking environment (DMPC/DHPC bicelles)(1) ) by heteronuclear (1) H,(13) C,(15) N-NMR spectroscopy. Interaction with the bicelles stabilizes the Aam-I right-handed helical conformation retaining significant intramolecular mobility on the ms-µs time scale. Extensive ms-µs dynamics were also detected in the DPC and DHPC micelles and DOPG nanodiscs. In contrast, Zrv-IIB in the DPC micelles demonstrates appreciably lesser mobility on the µs-ms time scale. Titration with Mn(2+) and 16-doxylstearate paramagnetic probes revealed Aam-I binding to the bicelle surface with the N-terminus slightly immersed into hydrocarbon region. Fluctuations of the Aam-I helix between surface-bound and transmembrane (TM) state were observed in the nanodisc membranes formed from the short-chain (diC12 : 0) DLPC/DLPG lipids. All the obtained experimental data are in agreement with the barrel-stave model of TM pore formation, similarly to the mechanism proposed for Zrv-IIB and other peptaibols. The observed extensive intramolecular dynamics explains the relatively low activity of Aam-I.

Morphological features of Late Ordovician (Sandbian) bryozoans from the basin of Khrevitsa River (north-western Russia) and description of a new species of the genus Prophyllodictya Gorjunova, 1987.

Some Sandbian (Late Ordovician) bryozoans are here described from the Leningrad region, north-western Russia. The studied association is represented by eight species including one new cryptostome bryozoan Prophyllodictya khrevitsa n. sp. We explore the colony morphology and evolutionary morphogenesis of Prophyllodictya Gorjunova, 1987 and discuss the morphological features of trepostome and cryptostome bryozoans from the Khrevitsa Formation. Finally, we classify protective structures in bryozoan colonies in three groups based on functional criteria: 1) structures to strengthen the colony, 2) structures to defend the colony against predators, and 3) structures to protect the polypide.

African Platyplectrus Ferrire (Hymenoptera: Eulophidae) from Kenya, with description of nine new species.

Eleven species of Platyplectrus have been recorded from the Afrotropical region. Ch. Ferrire described nine species in 1941: two of them as Platyplectrus (P. capensis and P. ornatus) and seven under Euplectromorpha (Platyplectrus ausensis, P. brevicornis, P. kiambuensis, P. obscuratus, P. nitidiceps, P. striolata and Euplectromorpha variegata (not synonymized until the present paper)). Subsequently, P. meruensis was described by Delucchi (1962) and P. desertus by Yefremova (2008). To date, only one species, P. kiambuensis, has been recorded from Kenya. Recently, a wide-ranging survey and inventory project in Kenya raised this number to 18 species, nine of which are new and described herein: Platyplectrus albiclavatus sp. nov., P. kayaensis sp. nov., P. marenjeensis sp. nov., P. mrimaensis sp. nov., P. ngangaoensis sp. nov., P. nyambeneensis sp. nov., P. nyanzaensis sp. nov., P. pseudoornatus sp. nov., and P. pyrrhomaculatus sp. nov. Three species are redescribed: two for both sexes (P. meruensis, P. obscuratus) and one for females (P. ornatus). A new combination is proposed for Platyplectrus striolatus (Ferrire) from Euplectromorpha striolata Ferrire, 1941, and Euplectromorpha variegata Ferrire, 1941 is synonymized with Platyplectrus nigroflaveatus Yefremova, and the female is redescribed. A key to the genus Platyplectrus is provided for the 18 species found in Kenya.

Resolving old problems with layered polytungstates related to hexagonal tungsten bronze: phase formation, structures, crystal chemistry and some properties.

A 60-year-old problem with the atomic arrangements and exact compositions of alkali polytungstates related to hexagonal tungsten bronze (HTB) was solved. The systems A2WO4-WO3 (A = K, Rb) were restudied and the average monoclinic layered structures of stoichiometric polytungstates A4W11O35 (A = K, Rb, Cs, Tl) and A2W7O22 (A = K, Rb, Cs) were first successfully determined. The structures resemble those of "MoW11O36" and "MoW14O45" (J. Graham and A. D. Wadsley, Acta Crystallogr., 1961, 14, 379-383) and are derived from HTB by breaking into slabs parallel to (100) due to the ordered omission of some [WO]∞ chains along the hexagonal tunnels. The slabs in A4W11O35 (A = Cs, Tl) and A2W7O22 (A = Rb, Cs) are mutually shifted by the a/2 HTB unit cell axis. These data mainly confirmed our preliminary structural models of HTB-like alkali polytungstates (S. F. Solodovnikov, N. V. Ivannikova, Z. A. Solodovnikova and E. S. Zolotova, Inorg. Mater., 1998, 34, 845-853) and revealed a new similar thallium polytungstate. The structures of the HTB-like polytungstates and related compounds form a homologous series of layered complex oxides or fluorides An+2-xM3n+2X9n+8 where n = 2, 3 and 4 are equal to the numbers of HTB hexagonal tunnels across the polytungstate slab width for Tl2W4O13, A4W11O35 and A2W7O22 (A = K, Rb, Cs or Tl), respectively. The structures of the HTB-like polytungstates seem to intergrow with HTB-type AxWO3 to form, in particular, higher homologues of the series. Our group-supergroup analysis, measurements of nonlinear optical activity and electrical conductivity, and calculations of the bond-valence site energy barriers indicate possible ferroelectric/ferroelastic properties and moderate 2D oxide-ion mobility within the HTB-type slabs of the studied polytungstates.

Year-Round Presence of Microcystins and Toxin-Producing Microcystis in the Water Column and Ice Cover of a Eutrophic Lake Located in the Continuous Permafrost Zone (Yakutia, Russia).

This study aimed to test the hypothesis of the year-round presence of toxigenic Microcystis and cyanotoxins in the water and ice of the shallow eutrophic Lake Ytyk-Kyuyol located in the continuous permafrost zone. Three independent approaches-mass-spectrometry, molecular methods and light microscopy-were applied in the study. The cyanobacterial biomass ranged from 1.0 × 10-4 to 4.8 mg L-1. Microcystis flos-aquae and M. aeruginosa were the dominant morphospecies in plankton throughout the observation. In environmental DNA, the presence of M. aeruginosa was supported and mcy gene regions responsible for microcystin biosynthesis were detected through a BLAST (Basic Local Alignment Search Tool) search and phylogenetic estimation based on newly obtained 16S rRNA, 16S-23S ITS rRNA, mcyA and mcyE nucleotide sequences. The intracellular microcystin concentration ranged from <0.1 to 803 ng L-1, and the microcystin quota in the Microcystis biomass was extremely low. For the first time, it was shown that Microcystis cells containing mcy genes and microcystins presented permanently in the water column, both during the ice-free period and under ice, as well as inside thick ice covers within 7 months of severe winter. We hypothesized that minor pelagic and ice populations of Microcystis could participate in increasing cell density in the spring. However, further studies are needed to confirm the viability of the overwintering Microcystis colonies in the water and inside the ice of Lake Ytyk-Kyuyol.

Insight into the electronic structure, optical properties, and redox behavior of the hybrid phthalocyaninoclathrochelates from experimental and density functional theory approaches.

An insight into the electronic structure of several hafnium(IV), zirconium(IV), and lutetium(III) phthalocyaninoclathrochelates has been discussed on the basis of experimental UV-vis, MCD, electro- and spectroelectrochemical data as well as density functional theory (DFT) and time-dependent DFT (TDDFT) calculations. On the basis of UV-vis and MCD spectroscopy as well as theoretical predictions, it was concluded that the electronic structure of the phthalocyninoclathrochelates can be described in the first approximation as a superposition of the weakly interacting phthalocyanine and clathrochelate substituents. Spectroelectrochemical data and DFT calculations clearly confirm that the highest occupied molecular orbital (HOMO) in all tested complexes is localized on the phthalocyanine ligand. X-ray crystallography on zirconium(IV) and earlier reported hafnium(IV) phthalocyaninoclathrochelate complexes revealed a slightly distorted phthalocyanine conformation with seven-coordinated metal center positioned ∼1 Šabove macrocyclic cavity. The geometry of the encapsulated iron(II) ion in the clathrochelate fragment was found to be between trigonal-prismatic and trigonal-antiprismatic.