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2. Behavioristic Counseling Model Based On Audiovisual Media to Increase Solidarity In Junior High School Students

Author

Bau Ratu Bau, Dhevy Puswiartika, Syahril, Yusdin Gagaramusu, Suhrah, and Ninil Elfira

Subjects
solidarity, counseling behavioristic, role play collaboration., Education
Abstract

This article discusses the behavioristic counseling model of role-play collaboration techniques based on audiovisual media to increase the solidarity of state junior high school students in the Sigi district. This study aims to implement the audiovisual media-based behavioral counseling model of role-play collaboration techniques to increase student solidarity. increasing student solidarity is expected to minimize the occurrence of conflicts between students and contribute to creating peaceful schools. This study used the Research and Development (R&D) method. Data collection techniques in this study used interviews and questionnaires. The results of the study show that: (1) the average score of all assessment subjects as much as 93% of guidance and counseling teachers stated that counseling models and guidelines were very easy to implement. (2) based on the recapitulation table of student responses, it shows that the strongly agree category is 93.12%, which indicates a behavioristic counseling model, role play collaboration techniques based on audiovisual media, can increase the solidarity of junior high school students in Sigi Regency

Published
2024
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4. Transition metal derivatives of a ((dimethylamino)ethyl)cyclopentadienyl ligand. Synthesis and structures of amino-containing cyclopentadienyl derivatives of cobalt(I) and -(III) including water-soluble compounds

Author

Philippopoulos, A.I., Bau, R., Poilblanc, R., and Hadjiliadis, N.

Subjects
Organometallic compounds -- Research, Cobalt -- Research, Transition metals -- Research, Cyclopentadiene -- Research, Chemistry
Abstract

The synthesis of the organometallic complexes of Co(I) and Co(III) with the same ligands using either the functionalized cyclopentadiene or its Li15, or Na16 salts is described. Cyclopentadienyllithium or -sodium salts are used as reagents for the introduction of cyclopentadienyl ligands. Results implied that metallocene-type complexes and half-sandwich compounds of cobalt containing the ((dimethylamino)ethyl)cyclopentadienyl ligand can be synthesized easily. It was also observed that protonated Co(III) complexes can be characterized by special solubility in water and polar solvents.

Published
1998

6. On the mechanism of action of thiamin enzymes, crystal structure of 2-(alpha-hydroxyethyl)thiamin pyrophosphate (HETPP). Complexes of HETPP with zinc(II) and cadmium(II)

Author

Malandrinos, G., Louloudi, M., Mitsopoulou, C. A., Butler, I. S., Bau, R., and Hadjiliadis, N.

Subjects
spectroscopy, thiamin metal complexes, chloride, cd2+, diphosphate dependent enzyme, hydrochloride, resolution, vitamin-b-1, thiamin, spectroscopic characterization, derivatives, thiamin catalysis, transketolase, zn2+
Abstract

The crystal structure of the 2-(alpha-hydroxethyl) thiamin pyrophosphate (LH2) was solved by X-ray diffraction. Crystallographic data: space group F2dd, a = 7.922(4) Angstrom, b = 33.11(2) Angstrom, c = 36.232(10) Angstrom, V = 9503(9) Angstrom(3), z = 16. Metal complexes of the general formula K-2{[M(LH)Cl-2](2)} (M = Zn2+, Cd2+) were isolated from methanolic solutions and characterized by elemental analysis, IR, Raman, and C-13 CP MAS NMR spectra. They were also characterized by C-13 NMR, P-31 NMR, Cd-113 NMR, ES-MS, and H-1 NMR ROESY spectra in D2O solutions. The data provide evidence for the bonding of the metals to the N(1') atom of the pyrimidine ring and to the pyrophosphate group. The free ligand and the metal-coordinated ligand adopt the S conformation. Since thiamin cofactor, substrate, and metal ions are present in our system, the extracted results directly refer to thiamin catalysis and possible functional implications are correlated and discussed. Journal of Biological Inorganic Chemistry

Published
1998

7. On the mechanism of action of thiamin enzymes, crystal structure of 2- (α-hydroxyethyl)thiamin pyrophosphate (HETPP). Complexes of HETPP with zinc(II) and cadmium(II)

Author

Malandrinos, G. Louloudi, M. Mitsopoulou, C.A. Butler, I.S. Bau, R. Hadjiliadis, N.

Abstract

The crystal structure of the 2-(α-hydroxethyl) thiamin pyrophosphate (LH2) was solved by X-ray diffraction. Crystallographic data: space group F2dd, a=7.922(4) Å, b=33.11(2) Å, c=36.232(10) Å, V=9503(9) Å3, z=16. Metal complexes of the general formula K2[M(LH)Cl2]2 (M=Zn2+, Cd2+) were isolated from methanolic solutions and characterized by elemental analysis, IR, Raman, and 13C CP MAS NMR spectra. They were also characterized by 13C NMR, 31P NMR, 113Cd NMR, ES-MS, and 1H NMR ROESY spectra in D2O solutions. The data provide evidence for the bonding of the metals to the N(1’) atom of the pyrimidine ring and to the pyrophosphate group. The free ligand and the metal-coordinated ligand adopt the S conformation. Since thiamin cofactor, substrate, and metal ions are present in our system, the extracted results directly refer to thiamin catalysis and possible functional implications are correlated and discussed.

Published
1998

8. Complexes of Zn2+, Cd2+, and Hg2+ with 2-(alpha-hydroxybenzyl)thiamine monophosphate chloride

Author

Dodi, K., Gerothanassis, I. P., Hadjiliadis, N., Schreiber, A., Bau, R., Butler, I. S., and Barrie, P. J.

Subjects
thiamine, nmr-spectra, molecular-structure, chemical-shift tensors, vitamin-b1, derivatives, mercury(ii), crystal-structure, solid-state, metal-complexes
Abstract

The binding sites of Zn2+, Cd2+, and Hg2+ in complexes with 2-(alpha-hydroxybenzyl)thiamine monophosphate chloride, (LH)Cl-+(-), have been investigated in the solid state [2-(alpha-hydroxybenzyl)thiamin monophosphate chloride monoprotonated at the phosphate group and protonated at N-1' is denoted as (LH)Cl-+(-); therefore, the ligand monoprotonated at the phosphate group and deprotonated at N-1' is L]. Complexes of formulae MLCl(2), M(LH)Cl-3, and (MCl(4))(2-)(LH)(2)(+) (M = Zn2+, Cd2+, and Hg2+) were isolated in aqueous and methanolic solutions, depending on pH. The crystal structure of the complex of formula HgL(2)Cl(2) was solved, together with that of the free ligand (LH)Cl-+(-), by X-ray crystallography. HgL(2)Cl(2) crystallizes in C2/c, with a = 32.968(6) Angstrom, b = 7.477(2) Angstrom, c = 21.471(4) Angstrom, beta = 118.19(1)degrees, V = 4665(2) Angstrom(3), and Z = 4. (LH)Cl-+(-) crystallizes in Cc, with a = 10.951(3) Angstrom, b = 17.579(4) Angstrom, c = 13.373(3) Angstrom, beta = 105.36(2)degrees, V = 2482.4(10) Angstrom(3), and Z = 4. Mercury(II) binds to the N(1') of the pyrimidine ring. Both ligands are in the S conformation [Phi(T) = -98.1(9)degrees and Phi(P) = 176.1(10)degrees for HgL(2)Cl(2) and Phi(T) = 104.1(5)degrees and Phi(P) = 171.9(6)degrees for (LH)Cl-+(-)]. P-31 and C-13 NMR spectra, together with vibrational spectra (IR/Raman), are used to deduce the binding sites of the metal and the protonation states of the ligand at various pH values. It is found that solid-state P-31 NMR spectroscopy is particularly useful in characterizing these complexes as the P-31 shielding tensors are sensitive to the state of the phosphate group. On the other hand, the P-31 NMR spectra indicate that direct bonding between Zn2+ and Cd2+ to the phosphate can occur under certain preparation conditions. Solid-state C-13 NMR and vibrational (IR/Raman) spectroscopic results are also in agreement with the other techniques. Inorg Chem

Published
1996

9. Reaction of the Biheteroaromatic Ligand 2-(2'-Pyridyl)Quinoxaline (L) with Zinc(Ii) and Cadmium(Ii) Halides - Preparation and Characterization of the 1/1 Complexes

Author

Perlepes, S. P., Kasselouri, S., Garoufis, A., Lutz, F., Bau, R., and Hadjiliadis, N.

Subjects
spectra, molecular-structures, crystal-structure, coordination-compounds, chemistry, metal-complexes, copper(i)
Abstract

The reactions of ZnX(2) and CdX(2) (X = Cl, Br, I) with the biheteroaromatic ligand 2-(2'-pyridyl)quinoxaline (L) were studied in ethanolic solutions. The new complexes [ZnX(2)L] (X = Cl, Br, I), [CdI(2)L] and [Cd(2)X(4)L(2)] were isolated and characterized by elemental analyses, conductivity measurements, X-ray powder patterns, thermal methods (TG/DTG, DTA) and spectroscopic (IR, far-IR, Raman, H-1 NMR) studies. The X-ray crystal structure of [ZnCl(2)L] . 0.5MeOH shows a distorted tetrahedral geometry around the zinc(II) atom. The ligand L acts as a bidentate chelate with the ligated atoms being the pyridine nitrogen and one of the quinoxaline nitrogens. A monomeric pseudo-tetrahedral structure is also assigned for [ZnBr2] and [MI(2)L] (M = Zn, Cd). Dimeric structures are proposed for the chloro and bromo cadmium(II) compounds, in which the two metal centres are bridged by two halo ligands, with a terminal halide and a chelating molecule of L completing five-coordination at each metal. All data are discussed in terms of the nature of bonding and known and assigned structures. A complex with the empirical formula Cd(2)Cl(4)L was isolated during the thermal decomposition of [Cd(2)Cl(4)L(2)]; the vibrational study of this thermally stable intermediate shows that L acts as a tridentate bridging ligand. The crystal structure of [Hg(2)Br(4)L(2)], which was not available when the results of the HgX(2)/L chemistry had been published, is also described. Polyhedron

Published
1995

40. Spin crossover in iron(II)-complexes.

Author

Clarke, Michael J., Goodenough, John B., Hemmerich, Peter, Ibers, James A., Jørgensen, C. Klixbüll, Neilands, Joe B., Reinen, Dirk, Weiss, Raymond, Williams, Robert Joseph P., Bau, R., Gütlich, P., Teller, R. G., and Gütlich, Philipp

Published
1981
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41. Internal medicine. Comparison of prevalence and female sexual dysfunction between diabetic and non-diabetic in kelantan.

Author

Bau R, Ismail AH, Noor NM, and Sidi H

Abstract

Objective: To determine the prevalence and compare the types of female sexual dysfunction between diabetics and non-diabetics. ' Design: Cross-sectional study Materials and Methods: The study was conducted on 178 diabetic women and 175 non-diabetic women in Out Patient Clinic and Diabetic Centre in Hospital Universiti Sains Malaysia using systematic random sampling. Malay Version of Female Sexual Function Index was used. Data was entered and analysed by SPSS 12 0 using descriptive and Simple Logistic Regression analyses. ' Results: The prevalence of sexual dysfunction among diabetics was 26.4% and among non-diabetics was 20.0%. Arousal disorder was reported in 28.7% diabetics and 17.1% non-diabetic (p value 0.040). Sexual satisfactions disorder among diabetics and non-diabetics was 15.2% and 8.0% respectively (p value 0.042). Conclusion: The prevalence of female sexual dysfunction among diabetics was 26.4% and among non-diabetics was 20.0%. Screening for sexual dysfunction should be part of general screening especially among diabetics and interventions were advice. [ABSTRACT FROM AUTHOR]

Published
2010

42. ChemInform Abstract: Bromide Ion Catalyzed Dimerization of 3,3‐Diphenyl‐6‐oxa‐3‐silabicyclo( 3.1.0)hexane. Structure Determination and Ring Contraction of 2,2,6,6‐ Tetraphenyl‐4,8‐divinyl‐1,5‐dioxa‐2,6‐disilacyclooctane and Synthesis of 2,2,4,4‐Tetraphenyl‐6‐vinyl‐1,3‐dioxa‐2,4‐disilacyclohexane.

Author

PARK, Y. T., primary, MANUEL, G., additional, BAU, R., additional, ZHAO, D., additional, and WEBER, W. P., additional

Published
1991
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50. α-Agostic Interactions in Cp*W(NO)(CH<INF>2</INF>CMe<INF>3</INF>)<INF>2</INF> and Related Nitrosyl Complexes

Author

Bau, R., Mason, S. A., Patrick, B. O., Adams, C. S., Sharp, W. B., and Legzdins, P.

Abstract

The solid-state molecular structure of Cp*W(NO)(CH2CMe3)2 (1) has been shown to contain one “strongly agostic” and one “weakly agostic” methylene hydrogen atom by a neutron diffraction analysis at 120 K and by an X-ray diffraction analysis at −100 °C. The X-ray diffraction analysis of Cp*W(NO)(CH2SiMe3)2 (2) at −20 °C reveals that its solid-state molecular structure possesses a crystallographically imposed mirror plane. Consequently, only the average existence of a relatively strong C−H···M interaction for each hydrocarbyl ligand in 2 in the solid state can be established. The 1H and gated 13C{1H} NMR spectra of representative Cp‘M(NO)(R)(R‘) (M = Mo, W; R = hydrocarbyl, R‘ = hydrocarbyl, halide, amide) complexes exhibit spectral parameters for the α-H and α-C atoms (i.e., δH, δC, ΔδH, ΔJHC, and JHW) that provide evidence for the presence of α-agostic interactions in the molecular structures of these complexes in solution. The picture that has emerged from these investigations is that these complexes do adopt an α-agostic structure both in solution and in the solid state when secondary interactions such as π-electron donation are weak (as in Cp*W(NO)(CH2CMe3)Cl), competitive (as in Cp*W(NO)(CH2CMe3)(CH2Ph)), or not possible (as in Cp*W(NO)(hydrocarbyl)2 complexes generally). The bis(hydrocarbyl) complexes are probably stereochemically nonrigid in solution, as they appear to interconvert between the two limiting structures having one strongly agostic and one weakly agostic hydrocarbyl ligand. The neopentyl ligand forms α-agostic linkages with the metal centers in all neopentyl complexes studied, and these agostic interactions appear to be independent of the nature of the metal or the ancillary cyclopentadienyl ligand. Interestingly, the presence of these ground-state agostic interactions does not correlate with the tendency of the various compounds to undergo intramolecular α-H abstraction reactions and form reactive alkylidene complexes.

Published
2001

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