The structure of 3[beta],20[alpha]-bis(dimethylamino)pregn-5-en-18-ol

Abstract. C25H44N20 , M r= 388.6, orthorhombic, P21212 I, a = 6.185 (2), b = 18.123 (2), c = 20.852 (2) A, U= 2337.2 A 3, Z = 4, D x = 1.104 Mg m -a, 2(Cu Ka) = 1.5418 A,/~ = 0.47 mm -~, F(000) = 864, T= 293 K. Final R - 0.038 for 1791 reflections with I >_ 3a(I). Rings A and C are in chair conformation. Ring B is in an 8fl,9a-half-chair conformation. Ring D adopts a conformation in between 13fl,14a-half-chair and 13t-envelope. There is a quasitrans fusion of rings A and B, whilst ring systems B/C and C/D are trans fused about the bonds C(8)-C(9)and C(13)-C(14).

Työhön liittyvä kilpailu 18 - 65-vuotiaiden pyhtääläisten kuvaamana

Tutkimuksen kohteena olivat Pyhtään työikäisten asukkaiden näkemykset ja kokemukset työssä esiintyvästä kilpailusta Tutkimusongelma oli työhön liittyvän kilpailun ilmiön hahmottaminen. Tutkimuksen tarkoitus oli valottaa työhön liittyvän kilpailun moninaisuutta antaen esimerkkejä sen eri muodoista, esittäen ajatuksia uusien tulkintojen tekemiselle ja herättäen ideoita kilpailun eri muotojen soveltamiselle työn ja työilmapiirin tutkimuksissa. Tavoitteena oli tutkia haastatteluissa esiintyviä tapoja käsittää työhön liittyvä kilpailu ja sitä, missä määrin eri ammateissa kuvattiin sosiaalista kilpailua verrattuna välineelliseen kilpailuun. Työyhteisöön samastumista tarkasteltiin kilpailun ja koetun oikeudenmukaisuuden näkökulmista. Työn arvostusta käsiteltiin tarkastellen haastateltujen käsitystä ammattinsa yleisestä arvostuksesta sekä haastateltujen omia arvioita ammatistaan, sekä millä tavalla ammattirooli nousi esiin haastateltujen itsen kuvauksissa. Työpaikan ihmissuhteita ja valtaa tarkasteltiin kohdistamalla huomio työtovereiden kanssa toimeen tulemiseen ja työpaikan ihmissuhteiden aiheuttamaan stressiin sekä haastateltujen työssään kokeman oman vaikutusvallan, tasavertaisuuden, epäreiluuden, arvostuksen ja kilpailun määrään. Selvitettiin myös miten vallankäyttöä ja kiusaamista kuvattiin ja millä tavalla vallankäytön ja kiusaamisen katsottiin edesauttavan tavoitteiden saavuttamisessa. Lopuksi tarkastelun kohteina olivat ongelmien käsittely, työssä viihtyminen ja viihtymiseen vaikuttavat seikat. Aineisto kerättiin Pyhtäällä kesällä 2007. Vastaajia oli yhteensä 245 ja vastausprosentti oli 50. Tutkimuksessa mukana olivat kalkki työilmapiiriä ja työpaikan ihmissuhteita koskeviin kysymyksiin vastanneet haastatellut (N = 167). Suurimmaksi osaksi tutkimus oli kuvailevaa, mutta siinä oli myös kvantitatiivista kysymyksenasettelua. Tutkimuksessa käytettiin sekä kvalitatiivisia että kvantitatiivisia analyysimenetelmiä. Puolistrukturoiduissa yksilöhaastatteluissa hyödynnettiin tulkitsevaa fenomenologista analyysia. Kirjattuja avovastauksia tutkittiin luokittavalla ja tulkitsevalla sisällönanalyysilla. Lisäksi laskettiin tilastollisia merkitsevyyksiä Työpaikalla esiintyvä kilpailu nähtiin haastateltujen selonteoissa hyvin moninaisena, sekä myönteisenä että haitallisena. Siihen ymmärrettiin kuuluvan niin resursseihin, työtehtäviin, tuloksiin ja palkkioihin liittyvää välineellistä kilpailua, kuin ihmisten välistä sosiaalista valtataisteluakin. Suhteessa välineelliseen kilpailuun sosiaalista kilpailua kuvattiin eniten hoiva- ja sosiaalialan ammateissa. Suhteessa sosiaaliseen kilpailuun välineellistä kilpailua kuvasivat eniten yrittäjät Vastausten perusteella suun kilpailun määrä korreloi työpaikan ihmissuhteiden aiheuttamaan stressiin, mutta vain silloin, kun kokemus työpaikan oikeudenmukaisuudesta oli matala. Kilpailun eri muotojen (kilpailu omien tavoitteiden saavuttamisesta vs. kilpailu organisaation tavoitteiden saavuttamisesta) väliset yhteydet työyhteisöön samastumiseen eivät aineistossa olleet tilastollisesti merkitseviä. Haastatellun arvio oman ammattinsa arvostuksesta ei myöskään ennustanut haastatellun todennäköisyyttä esittää itsensä ammattikuntansa edustajana avoimen itsen kuvauksen tilanteessa. Koettu oikeudenmukaisuus kuitenkin korreloi työyhteisöön samastumiseen. Mitä oikeudenmukaisempana haastatellut työpaikkaansa pitivät, sitä tärkeämmäksi samastumiskohteeksi he sen tyypillisesti arvioivat. Myös työssä viihtymisen ja työpaikan koetun oikeudenmukaisuuden välinen korrelaatio oli aineistossa voimakas. Lisäksi silloin, kun kokemus oikeudenmukaisuudesta oli matalalla tasolla, oli myös työpaikan ihmissuhteiden aiheuttama stressi yhteydessä vähäiseen työssä viihtymiseen. Tärkeimmät läheet tutkimuksessa olivat: Turner. John C 1975. Social comparison and social identity. Some prospects for intergroup behaviour. European Journal of Social Psychology, 5(1), 5-34. Haslam, S. Alexander 2004. Psychology in organizalions. The social identity approach Second Edition. London: SAGE Publications. Tyler, Tom - Blader. Steven 2000. Cooperation in Groups: Procedural Justice, Social Identity, and Behavioural Engagement. Essays in Social Psychology. Philadelphia: Psychology Press / Taylor & Francis Group. Kantolahti, T. - Tikander, T. 2010. Puheenvuoroja työn kuormittavuudesta. Sosiaali- ja terveysministeriön selvityksiä 2010:17

Solvation and axial ligation properties of (2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetraphenylporphyrinato)zinc(II)

he solvation of (2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetraphenylporphyrinato)zinc(II)[Zn(obtpp)], in twelve different solvents results in large red shifts of the B and Q bands of the porphyrin accompanied by enhanced absorbance ratios of the Q bands. These observations are ascribed to the destabilisation of the highest occupied molecular orbital a2u of the porphyrin arising from a flow of charge from the axial ligand to the porphyrin ring through the zinc(II) ion. The binding constants of adducts of [Zn(obtpp)] with neutral bases have been found to be an order of magnitude greater than those observed for the corresponding adducts of (5,10,15,20-tetraphenylporphyrinato)-zinc and vary in the order piperidine > imidazole > pyridine > 3-methylpyridine > pyridine-3-carbaldehyde. The enhanced binding constants and large spectral shifts are interpreted in terms of the electrophilicity of [Zn(obtpp)] induced by the electron-withdrawing bromine substituents in the porphyrin core. The structure of [Zn(obtpp)(PrCN)2] has been determined; it reveals six-co-ordinated zinc(II) with two long Zn–N distance [2.51(4), 2.59(3)Å]. The porphyrin is non-planar and displays a saddle-shaped conformation.

Formation of a G-quadruplex at the BCL2 major breakpoint region of the t(14;18) translocation in follicular lymphoma

The t(14;18) translocation in follicular lymphoma is one of the most common chromosomal translocations. Most breaks on chromosome 18 are located at the 3'-UTR of the BCL2 gene and are mainly clustered in the major breakpoint region (MBR). Recently, we found that the BCL2 MBR has a non-B DNA character in genomic DNA. Here, we show that single-stranded DNA modeled from the template strand of the BCL2 MBR, forms secondary structures that migrate faster on native PAGE in the presence of potassium, due to the formation of intramolecular G-quadruplexes. Circular dichroism shows evidence for a parallel orientation for G-quadruplex structures in the template strand of the BCL2 MBR. Mutagenesis and the DMS modification assay confirm the presence of three guanine tetrads in the structure. 1H nuclear magnetic resonance studies further confirm the formation of an intramolecular G-quadruplex and a representative model has been built based on all of the experimental evidence. We also provide data consistent with the possible formation of a G-quadruplex structure at the BCL2 MBR within mammalian cells. In summary, these important features could contribute to the single-stranded character at the BCL2 MBR, thereby contributing to chromosomal fragility.

18-Bit binary inductive voltage divider for self balancing ac bridge applications

The constructional details of an 18-bit binary inductive voltage divider (IVD) for a.c. bridge applications is described. Simplified construction with less number of windings, interconnection of winding through SPDT solid state relays instead of DPDT relays, improves reliability of IVD. High accuracy for most precision measurement achieved without D/A converters. The checks for self consistency in voltage division shows that the error is less than 2 counts in 2(18).

Formation of a G-quadruplex at the BCL2 major breakpoint region of the t(14;18) translocation in follicular lymphoma

The t(14;18) translocation in follicular lymphoma is one of the most common chromosomal translocations. Most breaks on chromosome 18 are located at the 3'-UTR of the BCL2 gene and are mainly clustered in the major breakpoint region (MBR). Recently, we found that the BCL2 MBR has a non-B DNA character in genomic DNA. Here, we show that single-stranded DNA modeled from the template strand of the BCL2 MBR, forms secondary structures that migrate faster on native PAGE in the presence of potassium, due to the formation of intramolecular G-quadruplexes. Circular dichroism shows evidence for a parallel orientation for G-quadruplex structures in the template strand of the BCL2 MBR. Mutagenesis and the DMS modification assay confirm the presence of three guanine tetrads in the structure. 1H nuclear magnetic resonance studies further confirm the formation of an intramolecular G-quadruplex and a representative model has been built based on all of the experimental evidence. We also provide data consistent with the possible formation of a G-quadruplex structure at the BCL2 MBR within mammalian cells. In summary, these important features could contribute to the single-stranded character at the BCL2 MBR, thereby contributing to chromosomal fragility.

Conformation and orientation of alkyl chains in the layered organic-inorganic hybrids: (CnH2n+1NH3)(2)PbI4 (n=12,16,18)

Layered organic inorganic hybrids based on perovskite-derived alkylammonium lead halides have been demonstrated as important new materials in the construction of molecular electronic devices. Typical of this class of materials are the single-perovskite slab lead iodides of the general formula (CnH2n+1NH3)(2)PbI4. While for small n, these compounds are amenable to single-crystal structure determination, the increasing degree of disorder in the long chain (n = 12,14...) compounds makes such an analysis difficult. In this study, we use powder X-ray diffraction, and vibrational and C-13 NMR spectroscopies to establish the conformation, orientation and organization of hydrocarbon chains in the series of layered alkylammonium lead iodides (CnH2n+1NH3)(2)PbI4 (n = 12,16,18). We find that the alkyl chains adopt a tilted bilayer arrangement, while the structure of the inorganic layer remains invariant with respect to the value of n. Conformation-sensitive methylene stretching modes in the infrared and Raman spectra, as well as the C-13 NMR spectra indicate that bonds in the methylene chain are in trans configuration. The skeletal modes of the alkyl chain in the Raman spectra establish that there is a high degree of all-trans conformational registry for the values of n studied here. From the orientation dependence of the infrared spectra of crystals of (CnH2n+1NH3)(2)PbI4 ( n = 12,16), we find that the molecular axis of the all-trans alkyl chains are tilted away from the interlayer normal by an angle of 55degrees. This value of this tilt angle is consistent with the dependence of the c lattice expansion as a function of n, as determined from powder X-ray diffraction.

Phase transitions in the anchored organic bilayers of long-chain alkylammonium lead iodides (CnH2n+1NH3)(2)PbI4; n=12, 16, 18

The single perovskite slab alkylammonium lead iodides (CnH2n+1NH3)(2)PbI4, n = 12, 16, 18, display two phase transitions, just above room temperature, associated with changes in the alkylammonium chains. We have followed these two phase transitions using scanning calorimetry, X-ray powder diffraction, and IR and Raman spectroscopies. We find the first phase transition to be associated with symmetry changes arising from a dynamic rotational disordering of the ammonium headgroup of the chain whereas the second transition, the melting of the chains in two dimensions, is characterized by an increased conformational disorder of the methylene units of the alkyl chains. We examine these phase transitions in light of the interesting optical properties of these materials, as well as the relevance of these systems as models for phase transitions in lipid bilayers.

The 18 September 2011, North Sikkim earthquake

The 18 September 2011, magnitude Mw 6.9 earthquake close to the Nepal-Sikkim border caused significant damage due to ground shaking and caused several landslides. Observations from the post-earthquake surveys in the affected areas within Sikkim suggest that the poorly engineered, multistoried structures were relatively more impacted. Those located on alluvial terraces were also affected. The morphology of the region is prone to landslides and the possibility for their increased intensity during the forthcoming monsoon need to be considered seriously. From the seismotectonic perspective, the mid-crustal focal depth of the North Sikkim earthquake reflects the ongoing deformation of the subducting Indian plate.

Role of water contamination within the GC column of a GasBench II peripheral on the reproducibility of O-18/O-16 ratios in water samples

The GasBench II peripheral along with MAT 253 combination provides a more sensitive platform for the determination of water isotope ratios. Here, we examined the role of adsorbed moisture within the gas chromatography (GC) column of the GasBench II on measurement uncertainties. The uncertainty in O-18/O-16 ratio measurements is determined by several factors, including the presence of water in the GC. The contamination of GC with water originating from samples as water vapour over a longer timeframe is a critical factor in determining the reproducibility of O-18/O-16 ratios in water samples. The shift in isotope ratios observed in the experiment under dry and wet conditions correlates strongly with the retention time of analyte CO2, indicating the effect of accumulated moisture. Two possible methods to circumvent or minimise the effect of adsorbed water on isotope ratios are presented here. The proposed methodology includes either the regular baking of the GC column at a higher temperature (120 degrees C) after analysis of a batch of 32 sample entries or conducting the experiment at a low GC column temperature (22.5 degrees C). The effects of water contamination on long-term reproducibility of reference water, with and without baking protocol, have been described.

Mechanism of Fragility at BCL2 Gene Minor Breakpoint Cluster Region during t(14;18) Chromosomal Translocation

The t(14;18) translocation in follicular lymphoma is one of the most common chromosomal translocations. Breaks in chromosome 18 are localized at the 3'-UTR of BCL2 gene or downstream and are mainly clustered in either the major breakpoint region or the minor breakpoint cluster region (mcr). The recombination activating gene (RAG) complex induces breaks at IgH locus of chromosome 14, whereas the mechanism of fragility at BCL2 mcr remains unclear. Here, for the first time, we show that RAGs can nick mcr; however, the mechanism is unique. Three independent nicks of equal efficiency are generated, when both Mg2+ and Mn2+ are present, unlike a single nick during V(D)J recombination. Further, we demonstrate that RAG binding and nicking at the mcr are independent of nonamer, whereas a CCACCTCT motif plays a critical role in its fragility, as shown by sequential mutagenesis. More importantly, we recapitulate the BCL2 mcr translocation and find that mcr can undergo synapsis with a standard recombination signal sequence within the cells, in a RAG-dependent manner. Further, mutation to the CCACCTCT motif abolishes recombination within the cells, indicating its vital role. Hence, our data suggest a novel, physiologically relevant, nonamer-independent mechanism of RAG nicking at mcr, which may be important for generation of chromosomal translocations in humans.

Synthesis and spectral characterization of cyclotriphosphazene based 18-membered macrocycles

New 18-membered cyclotriphosphazene-containing macrocycles 7-10 were obtained by 1 + 1 condensation reaction of dispiro-N3P3(C12H8O2)(2)((N(Me)N=CH)(2) N4C20H26)] (2) with N,N'-dimethyl-ethylenediamine-1,4-diyldimethylenebis(4-methyl-2-formylph enol) (3), N,N'-dimethyl-ethylenediamine-1,4-diyldimethylenebis(4,5-dimethyl-2-form ylphenol) (4), N,N'-dimethyl-ethylenediamine-1,4-diyldimethylenebis(5-chloro-2-formylph enol) (5) and N,N'-dimethyl-ethylenediamine-1,4-diyldimethylenebis(5-bromo-2-formylphe nol) (6), respectively. (C) 2012 Elsevier B.V. All rights reserved.

Influence of the upwelling events on the delta C-13 and delta O-18 of the benthic bivalve shells of the South Western Continental Margin of India

In this study, the influence of the spatial and temporal variability of upwelling intensity and the associated biological productivity observed during different phases of summer monsoon along the southwestern continental margin of India (SWCMI) on the delta C-13 and delta O-18 of the inorganic biogenic carbonate shells was investigated. Multispecies benthic bivalve shells (1-5 mm) separated from ten surface sediment samples of SWCMI (off 12 degrees N, 10 degrees N and 9 degrees N) collected during the onset (OSM) and peak (PSM) phase of the summer monsoon of 2009 were analysed for delta C-13 and delta O-18. Sea surface temperature along the study region indicates prominent upwelling in PSM than in OSM. A comparison of analytical and predicted values for delta O-18 in the bivalve shells confirmed their in situ origin during both the sampling periods. During PSM, the delta C-13 values in the benthic bivalve shells were more depleted in C-13 than during OSM which recorded lower values of delta C-13 in dissolved inorganic carbon of bottom waters expected in the study region in PSM due to the upwelled waters, high surface productivity and the associated high degradation of the organic matter in the subsurface and bottom waters. However, this depletion of delta C-13 was not observed in benthic bivalve shells obtained from 10 degrees N, since it is influenced by high export fluxes of carbon from the Cochin estuary since early monsoon months.

Efecto de diferentes dosis de fertilizantes de la fórmula 18-46-0 y densidades de siembra sobre el crecimiento y rendimiento del frijol común (Phaseolus vulgaris) y la dinámica de las malezas

El presente experimento fue realizado en la Estación Experimental La Compañía, San Marcos, departamento de Carazo, durante la época de postrera del año 1991 con el fin de evaluar el efecto de diferentes dosis de fertilizante y densidades de siembra sobre la cenosis de las malezas, el crecimiento y rendimiento del frijol común. Los tratamientos, consistieron en combinar tres dosis de fertilizante de la fórmula 1846-0 (Testigo, 1 y 2 qq/mz de fertilizante) con tres densidades de siembra (15, 30 y 45 semillas/m2). Los resultados obtenidos en este trabajó muestran que bajo las condiciones en las que fue realizado el experimento, la aplicación de 2 qq/mz del fertilizante y una densidad de siembra de 45 semillas/m2, produjo la menor abundancia y cobertura de malezas. A dosis de 1 qq/mz y densidad de 30 semillas/m2 se obtuvo el menor peso seco de malezas. Durante el ciclo del cultivo la mayor diversidad de especies se registró en la clase monocotiledónea. En cuanto al cultivo, aun cuando se observó una ligera tendencia a disminuir el rendimiento a medida que aumentó la dosis de fertilizante aplicada no hubo diferencias. En el caso de las densidades, se obtuvo el mayor número de ramas y vainas con 15 semillas/m2 y el mayor número de plantas, peso de mil granos y rendimiento con 45 semillas/m2, aunque en todos los casos las diferencias fueron mínimas.