MNDO study of coupled strained hydrocarbons: Additivity of exocyclic C---C bond contraction induced by different ring systems

MNDO geometry optimizations were carried out on a series of symmetrically and unsymmetrically coupled strained ring hydrocarbons, R1-R1 and R1–R2 (R1=methyl, cyclopropyl, 1-bicyclo[1.1.0]butyl, 1-bicyclo[1.1.1]pentyl, prismyl, cubyl, 6-tricyclo [3.1.1.03,6]heptyl, and tetrahedryl groups; R2=methyl and cyclopropyl). The remarkable contraction of the C---C bond connecting the strained rings found experimentally in a few cases was reproduced correctly by the calculations. A linear correlation was found between the bond length shortening and the bond angle widening at the corresponding carbon atoms for all the structures considered. The reduction in C---C bond lengths due to various ring systems is additive. The additivity indicates that inter-ring interactions which effect the central bond length are absent and confirms the common electronic origin of bond contraction in these systems, viz. enhanced s-character in the exocyclic bonds of strained rings.

Periodontal and dental health and oral self-care among adults with diabetes mellitus.

ABSTRACT Bakhshandeh, Soheila. Periodontal and dental health and oral self-care among adults with diabetes mellitus. Department of Oral Public Health, Institute of Dentistry, Faculty of Medicine, University of Helsinki, Helsinki, Finland. 2011. 49 pp. ISBN 978-952-10-7193-5(paperback). The aim of the present study was to assess oral health and treatment needs among Iranian adults with diabetes according to socio-demographic status, oral hygiene, diabetes related factors, and to investigate the relation between these determinants and oral health. Moreover, the effect of an educational oral health promotion intervention on their oral health and periodontal treatment needs was studied. The target population comprised adults with diabetes in Tehran, Iran. 299 dentate patients with diabetes, who were regular attendants to a diabetic clinic, were selected as the study subjects. Data collection was performed through a clinical dental examination and self-administered structured questionnaire. The questionnaire covered information of the subject s social background, medical history, oral health behaviour and smoking. The clinical dental examinations covered the registration of caries experience (DMFT), community periodontal index (CPI) and plaque index (PI). The intervention provided the adults with diabetes dental health education through a booklet. Reduction in periodontal treatment needs one year after the baseline examination was used as the main outcome. A high prevalence of periodontal pockets among the study population was found; 52% of the participants had periodontal pockets with a pocket depth of 4 to 5 mm and 35% had periodontal pockets with pocket depth of 6 mm or more. The mean of the DMFT index was 12.9 (SD=6.1), being dominated by filled teeth (mean 6.5) and missing teeth (mean 5.0). Oral self-care among adults with diabetes was inadequate and poor oral hygiene was observed in more than 80% of the subjects. The educational oral health promotion decreased periodontal treatment needs more in the study groups than in the control group. The poor periodontal health, poor oral hygiene and insufficient oral self-care observed in this study call for oral health promotion among adult with diabetes. An educational intervention showed that it is possible to promote oral health behaviour and to reduce periodontal treatment needs among adults with diabetes. The simplicity of the model used in this study allows it to be integrated to diabetes programmes in particular in countries with a developing health care system.

Nucleotide sequence of the 3terminal region of belladonna mottle virus (renamed Physalis mottle virus) RNA and analysis of the evolutionary relationships among tymoviral coat proteins

The 3' terminal 1255 nt sequence of Physalis mottle virus (PhMV) genomic RNA has been determined from a set of overlapping cDNA clones. The open reading frame (ORF) at the 3' terminus corresponds to the amino acid sequence of the coat protein (CP) determined earlier except for the absence of the dipeptide, Lys-Leu, at position 110-111. In addiition, the sequence upstream of the CP gene contains the message coding for 178 amino acid residues of the C-terminus of the putative replicase protein (RP). The sequence downstream of the CP gene contains an untranslated region whose terminal 80 nucleotides can be folded into a characteristic tRNA-like structure. A phylogenetic tree constructed after aligning separately the sequence of the CP, the replicase protein (RP) and the tRNA-like structure determined in this study with the corresponding sequences of other tymoviruses shows that PhMV wrongly named belladonna mottle virus [BDMV(I)] is a separate tymovirus and not another strain of BDMV(E) as originally envisaged. The phylogenetic tree in all the three cases is identical showing that any subset of genomic sequence of sufficient length can be used for establishing evolutionary relationships among tymoviruses.

Roofed polyquinanes: synthesis and electronic structure

Starting from readily available norbornenobenzoquinone 7 and employing a photothermal metathesis reaction as the main strategy, novel "roofed" polyquinane bisenones 3 and 13 have been synthesized. Among these, the former is potentially serviceable for further elaboration to dodecahedrane 1. Catalytic hydrogenation of 3 provided the dione 12, which fully inscribes the circumference of dodecahedrane sphere. The "roofed" C-16-bisenone 3 has been successfully annulated to C19-bisenone 24 and C19-trisenone 26 by employing the Greene methodology and Pauson-Khand reaction, respectively. The molecular structures of 3 and 13 were computed using molecular mechanics and semiempirical MO methods. The nonbonded distances between the double bonds vary strongly with the method employed. The interactions between the pi-MO's were, therefore, probed by means of photoelectron (PE) spectroscopy. Comparison with the PE spectra of a series of model systems with increasing complexity enabled an unambiguous assignment of the observed peaks. The symmetric and antisymmetric combinations of the pi-MO's of the enone moieties of 3 and 13 show large splittings, characteristic of propano-bridged systems in which through-space and through-bond effects act in concert.

Reactions of Mixed-Valent Palladium (IV,II) Complexes of Tetradentate Schiff-Bases Involving Bond Isomerization

Reactions of [PdIVB-(AI)2]++ [PdIICl4]-- (i) B-(AI)2 = dianion of N,N'-ethylene-/i-propylene-/n-propylene-bis(acetyl-acetoneimine) with some π-acceptor ligands, aliphatic primary amines and nitrosating reagents have been investigated. In all these reactions except nitrosation, 1:1 adducts having the formula, [PdIVB-(AI)2.X] [PdIICl4] [X = triphenylphosphine (TPP), triphenylarsine (TPA), pyridine (Py), methylamine (CH3NH2) or ethylamine (C2H5NH2)] are obtained. The formation of these complexes is associated with a bond isomerization - from Pd-Cxo-π -allylic bond prevailing in [PdIVB-(AI)2]2+ to PdIV-O bonding.Reaction of (i) with nitrosating reagents reduces PdIV to PdII and subsequently transform the γ-CH group, into an ambidentate isonitroso group (°C = NOH). The latter enters into coordination with PdII by dislodging the already coordinated carbonyl group. Further, selective nitrosation (mono- and dinitrosation) has been carried out by controlling the amount of the nitrosating reagent and the reaction time. The complexes have been characterized by elemental analyses, electrical conductivity, magnetic susceptibility and ir spectral data.

The influence of lone-pair repulsions on C–C bond lengths: a critical evaluation of the experimental and theoretical evidence

X-Ray structural data, as well as semiempirical and ab initio molecular orbital calculations, reveal no systematic and substantial difference between the C–C bond lengths of cis and trans 1,2-diketones. Additional results on various conformations of 1,2-diimines and 1,2-dithiones follow the same pattern. Therefore, lone-pair repulsions cannot be implicated in the observed lengthening of C–C bonds in isatin and several related molecules. Conjugation in these systems occurs peripherally avoiding the participation of the central C–C bond. Negative hyperconjugative interaction between the oxygen lone pairs and the adjacent C–C σ* orbital is suggested to be the principal reason for the relatively long C–C bond in diketones. This effect is found in both the cis and trans conformations.

Leisure-time physical activity, health related functioning and retirement : a prospective cohort study among middle-aged employees

Physical inactivity has become a major threat to public health worldwide. The Finnish health and welfare policies emphasize that the working population should maintain good health and functioning until their normal retirement age and remain in good health and independence later in life. Health behaviours like physical activity potentially play an important role in reaching this target as physical activity contributes to better physical fitness and to reduced risk of major chronic diseases. The aim of this study was to examine first whether the volume and intensity of leisure-time physical activity impacts on subsequent physical health functioning, sickness absence and disability retirement. The second aim was to examine changes in leisure-time physical activity of moderate and vigorous intensity after transition to retirement. This study is part of the ongoing Helsinki Health Study. The baseline data were collected by questionnaires in 2000 - 02 among the employees of the City of Helsinki aged 40 to 60. The follow-up survey data were collected in 2007. Data on sickness absence were obtained from the employer s (City of Helsinki) sickness absence registers and pension data were obtained from the Finnish Centre for Pensions. Leisure-time physical activity was measured in four grades of intensity and classified according to physical activity recommendations considering both the volume and intensity of physical activity. Statistical techniques including analysis of covariance, logistic regression, Cox proportional hazards models and Poisson regression were used. Employees who were vigorously active during leisure time especially had better physical health functioning than those physically inactive. High physical activity in particular contributed to the maintenance of good physical health functioning. High physical activity also reduced the risk of subsequent sickness absences as well as the risk of all-cause disability retirement and retirement due to musculoskeletal and mental causes. Among those transferred to old-age retirement moderate-intensity leisure-time physical activity increased on average by more than half an hour per week and in addition the occurrence of physical inactivity reduced. Such changes were not observed among those remained employed and those transferred to disability retirement. This prospective cohort study provided novel results on the effects of leisure-time physical activity on health related functioning and changes in leisure-time physical activity after retirement. Although the benefits of moderate-intensity physical activity for health are well known these results suggest the importance of vigorous physical activity for subsequent health related functioning. Thus vigorous physical activity to enhance fitness should be given more emphasis from a public health perspective. In addition, physical activity should be encouraged among those who are about to retire.

Macroscopic model of city traffic using bond graph modelling

Modelling of city traffic involves capturing of all the dynamics that exist in real-time traffic. Probabilistic models and queuing theory have been used for mathematical representation of the traffic system. This paper proposes the concept of modelling the traffic system using bond graphs wherein traffic flow is based on energy conservation. The proposed modelling approach uses switched junctions to model complex traffic networks. This paper presents the modelling, simulation and experimental validation aspects.

A2MoTiO7−x (Atriple bond; length as m-dashrare earth or Y): a new series of oxide pyrochlores prepared by topochemical reduction of A2MoTiO8 scheelites

A series of anion-deficient pyrochlore oxides of the formula A2MoTiO7−x (xless-than-or-equals, slant0.5), where Atriple bond; length as m-dashSm, Gd, Tb, Dy, Ho, Er, Lu and Y, has been prepared by reduction of A2MoTiO8 scheelites. The scheelite-to-pyrochlore conversion is reversible, indicating that the reaction is likely to be topochemical. The oxidation states of molybdenum and titanium are most probably Mo(III) and Ti(IV) for the limiting composition of the pyrochlores A2MoTiO6.5. The new pyrochlores are non-metallic and paramagnetic as expected.

Attitudes towards suicide among Master’s degree students: a cross-cultural comparison between China and Finland

Attitudes towards suicide among Master’s degree students in Chang Sha (China) and Helsinki (Finland) were compared in order to explore possible cross-cultural differences. The sample included 206 Master’s degree students, 101 Chinese and 105 Finnish. Data were collected using the 30-item Multi-Attitudes Suicide Tendency Scale (MAST) and a demographic information form. According to the results, both Chinese and Finnish students held positive attitudes towards life, they held contradictory attitudes towards suicide, with Finnish students having more permissive and liberal attitudes towards suicide than their Chinese counterparts. In addition, three socio-demographic characteristics, namely religion, family structure, and economic status, associated with attitudes towards suicide among the Chinese Master’s degree students; meanwhile, all socio-demographic characteristics, including gender, religion, major subject, family structure, economic status, and received social support related to attitudes towards suicide among the Finnish Master’s degree students. However, after examining the interaction effect between socio-demographics and cultural backgrounds on attitudes towards suicide, the attitudes of Chinese students were more related to gender, marital status, family economic status, and received social support, whereas Finnish students were more influenced by religion. These findings suggest that culture plays an important role in shaping country-specific differences in attitudes towards suicide and their association with socio-demographic characteristics. Understanding individual attitudes towards suicide could help in intervention to prevent the development of suicidal ideation and in providing appropriate psychological counseling to reduce mental problems. Therefore, these cross-cultural differences may provide indications on how to conduct suicide prevention programs while considering culture-specific contexts.

Social and material deprivation among youth in Finland : causes, consequences, and coping.

Background: Social and material deprivation is associated with poor health, decreased subjective well-being, and limited opportunities for personal development. To date, little is known about the lived experiences of Finnish low-income youths and the general purpose of this study is to fill this gap. Despite the extensive research on socioeconomic income disparities, only a few scholars have addressed the question of how low socioeconomic position is experienced by disadvantaged people themselves. Little is known about the everyday social processes that lead to decreased well-being of economically and socially disadvantaged citizens. Data: The study is based on the data of 65 autobiographical essays written by Finnish low-income youths aged 14-29 (M=23.51, SD=3.95). The research data were originally collected in a Finnish nationwide writing contest “Arkipäivän kokemuksia köyhyydestä” [Everyday Experiences of Poverty] between June and September of 2006. The contest was partaken by 850 Finnish writers. Methods and key concepts: Autobiographical narratives (N=65) of low-income youths were analyzed based on grounded theory methodology (GTM). The analysis was not built on specific pre-conceived categorizations; it was guided by the paradigm model and so-called “sensitizing concepts”. The concepts this study utilized were based on the research literature on socioeconomic inequalities, resilience, and coping. Socioeconomic inequalities refer to unequal distribution of resources, such as income, social status, and health, between social groups. The concept of resilience refers to an individual’s capacity to cope despite existing risk factors and conditions that are harmful to health and well-being. Coping strategies can be understood as ways by which a person tries to cope with psychological stress in a situation where internal or externals demands exceed one’s resources. The ways to cope are cognitive or behavioral efforts by which individual tries to relieve the stress and gain new resources. Lack of material and social resources is associated with increased exposure to health-related stressors during the life-course. Aims: The first aim of this study is to illustrate how youths with low socioeconomic status perceive the causes and consequences of their social and material deprivation. The second aim is to describe what kind of coping strategies youths employ to cope in their everyday life. The third aim is to build an integrative conceptual framework based on the relationships between causes, consequences, and individual coping strategies associated with deprivation. The analysis was carried out through systematic coding and orderly treatment of the data based on the grounded theory methodology. Results: Finnish low-income youths attributed the primary causes of deprivation to their family background, current socioeconomic status, sudden life changes, and contextual factors. Material and social deprivation was associated with various kinds of negative psychological, social, and material consequences. Youths used a variety of coping strategies that were identified as psychological, social, material, and functional-behavioral. Finally, a conceptual framework was formulated to link the findings together. In the discussion, the results were compared and contrasted to the existing research literature. The main references of the study were: Coping: Aldwin (2007); Lazarus & Folkman (1984); Hobfoll (1989, 2001, 2002). Deprivation: Larivaara, Isola, & Mikkonen (2007); Lister (2004); Townsend (1987); Raphael (2007). Health inequalities: Dahlgren & Whitehead (2007); Lynch. et al. (2000); Marmot & Wilkinson (2006); WHO (2008). Methods: Charmaz (2006); Flick (2009); Strauss & Corbin (1990). Resilience: Cutuli & Masten (2009); Luthar (2006).

Factors Affecting Knowledge Sharing in Strategic Alliances: The Role of Knowledge Sharing as Strategic Control Behavior among Multinational Enterprises

International strategic alliances (ISAs) have become increasingly important for the stability, growth, and long-term viability of modern business organizations. Alliance partnerships as inter-firm cooperative ventures represent an influential mechanism for asserting corporate strategic control among autonomous multinational enterprises. These different cooperative arrangements are made of equity investments or contractually-based partnerships. Different alliance forms represent different approaches that partner firms adopt to control their mutual dependence on the alliance and on other partners. Earlier research shows that the partner characteristics could provide an explanation for alliance strategic behavior and see alliances as alternative forms to markets or hierarchies for addressing specific strategic needs linked to partners’ characteristics and their subsequent strategic motives. These characteristics of the partners’ and subsequent strategic motives are analyzed as knowledge sharing factors and how these influence inter-firm control in alliances within the context of the focal-firm STMicroelectronics and its alliance partners Nokia, Ericsson and IBM. This study underline that as contracts are incomplete, they are therefore required to maintain mutual dependence based control mechanisms in addition to a contract. For example, mutual dependence based control mechanisms could be joint financial investments and the building of an ownership structure between the parties (e.g., JVs). However, the present study clarifies that subsequent inter-firm control is also exercised through inter-firm knowledge sharing. The present study contributes by presenting a dynamic interplay between competitive and cooperative rent seeking behavior. Such coopetition behavior describes the firm's strategic orientation to achieve a dynamic balance between competitive and cooperative strategies. This balance is seen in knowledge sharing based cooperation and competition behavior. Thus this study clarifies coopetition strategies by introducing the role of inter-firm cooperation and the competitive nature of knowledge sharing. Simultaneous cooperative and competitive behavior is also seen as synergetic rent-seeking behavior. Therefore, this study extends the perspective of previous studies on competitive and cooperative seeking behavior.