Unraveling the packing pattern leading to gelation using SS NMR and X-ray diffraction: direct observation of the evolution of self-assembled fibers

A detailed understanding of the mode of packing patterns that leads to the gelation of low molecular mass gelators derived from bile acid esters was carried out using solid state NMR along with complementary techniques such as powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and polarizing optical microscopy (POM). Solid state C-13{H-1} cross polarization (CP) magic angle spinning (MAS) NMR of the low molecularmass gel in its native state was recorded for the first time. A close resemblance in the packing patterns of the gel, xerogel and bulk solid states was revealed upon comparing their C-13{H-1} CPMAS NMR spectral pattern. A doublet resonance pattern of C-13 signals in C-13{H-1}CPMAS NMR spectra were observed for the gelator molecules, whereas the non-gelators showed simple singlet resonance or resulted inthe formation of inclusion complexes/solvates. PXRD patterns revealed a close isomorphous nature of the gelators indicating the similarity in the mode of the packing pattern in their solid state. Direct imaging of the evolution of nanofibers (sol-gel transition) was carried out using POM, which proved the presence of self-assembled fibrillar networks (SAFINs) in the gel. Finally powder X-ray structure determination revealed the presence of two non-equivalent molecules in an asymmetric unit which is responsible for the doublet resonance pattern in the solid state NMR spectra.

The Relational Self, the Social Bond and the Dynamics of Personal Relationships : A Sociological Analysis

This study analyses personal relationships linking research to sociological theory on the questions of the social bond and on the self as social. From the viewpoint of disruptive life events and experiences, such as loss, divorce and illness, it aims at understanding how selves are bound to their significant others as those specific people ‘close or otherwise important’ to them. Who form the configurations of significant others? How do different bonds respond in disruptions and how do relational processes unfold? How is the embeddedness of selves manifested in the processes of bonding, on the one hand, and in the relational formation of the self, on the other? The bonds are analyzed from an anti-categorical viewpoint based on personal citations of significance as opposed to given relationship categories, such as ‘family’ or ‘friendship’ – the two kinds of relationships that in fact are most frequently significant. The study draws from analysis of the personal narratives of 37 Finnish women and men (in all 80 interviews) and their entire configurations of those specific people who they cite as ‘close or otherwise important’. The analysis stresses the subjective experiences, while also investigating the actualized relational processes and configurations of all personal relationships with certain relationship histories embedded in micro-level structures. The research is based on four empirical sub-studies of personal relationships and a summary discussing the questions of the self and social bond. Discussion draws from G. H. Mead, C. Cooley, N. Elias, T. Scheff, G. Simmel and the contributors of ‘relational sociology’. Sub-studies analyse bonds to others from the viewpoint of biographical disruption and re-configuration of significant others, estranged family bonds, peer support and the formation of the most intimate relationships into exclusive and inclusive configurations. All analyses examine the dialectics of the social and the personal, asking how different structuring mechanisms and personal experiences and negotiations together contribute to the unfolding of the bonds. The summary elaborates personal relationships as social bonds embedded in wider webs of interdependent people and social settings that are laden with cultural expectations. Regarding the question of the relational self, the study proposes both bonding and individuality as significant. They are seen as interdependent phases of the relationality of the self. Bonding anchors the self to its significant relationships, in which individuality is manifested, for example, in contrasting and differentiating dynamics, but also in active attempts to connect with others. Individuality is not a fixed quality of the self, but a fluid and interdependent phase of the relational self. More specifically, it appears in three formats in the flux of relational processes: as a sense of unique self (via cultivation of subjective experiences), as agency and as (a search for) relative autonomy. The study includes an epilogue addressing the ambivalence between the social expectation of individuality in society and the bonded reality of selves.

A Dynamic Migration Model for Self-adaptive Genetic Algorithms

In this paper, we propose a self Adaptive Migration Model for Genetic Algorithms, where parameters of population size, the number of points of crossover and mutation rate for each population are fixed adaptively. Further, the migration of individuals between populations is decided dynamically. This paper gives a mathematical schema analysis of the method stating and showing that the algorithm exploits previously discovered knowledge for a more focused and concentrated search of heuristically high yielding regions while simultaneously performing a highly explorative search on the other regions of the search space. The effective performance of the algorithm is then shown using standard testbed functions, when compared with Island model GA(IGA) and Simple GA(SGA).

Family mediation and women’s services: Towards effective referral

Central to Government’s strategy for separating families is the management and resolution of disputes away from courts and litigation processes wherever this is achievable. A key group of players in facilitating this vision are workers within the wide range of women’s services. This study surveyed workers at a number of Victorian women’s services that provide advice, support, and referral for women and explored their understanding of mediation processes and outcomes. The results indicate that, while generally supportive of mediation as a process that could assist their clients, workers were concerned about its appropriateness when family violence was an issue. Some of these concerns appeared to be based upon a good understanding of the limitations of mediation practices, but it is also apparent that some concerns were influenced by a misunderstanding and limited knowledge of contemporary mediation practice. It is recommended that family mediation services work proactively with women’s services in order to better inform each other of the possibilities and constraints in working with postseparation disputes.

Depression in / by / for women : agency, feminism and self-help in groups

Depression in / by / for Women: Agency, Feminism and Self-Help in Groups on ensimmäinen väitöstasoinen tutkimus feministisestä terapiasta Suomessa sijoittuen psykologian, sosiaalitieteellisen mielenterveystutkimuksen sekä feministisen tutkimuksen alueille. Perinteisen näkemyksen mukaan feministisen tutkimuksen tulee olla ”naisista, naisten tekemää ja naisille kohdistettua”. Naiset ja masennus -projektitutkimus keskittyy naisten kokemaan masennukseen sisältäen mahdollisen miesten sekä patriarkaalisen hyvinvointivaltion osuuden masennukseen. Masennusta kokevat naiset ovat tutkimuksessa sekä tutkimuksen kohteena että aktiivisia osanottajia, mikä tuo heidän äänensä kuuluville. Tutkimus perustuu vuosien 1994-2000 välisenä aikana kerättyyn 11 ryhmän osallistujia koskevaan kvalitatiivisiin ja kvantitatiivisiin aineistoon. Irmeli Laitinen on ollut suunnittelemassa, keräämässä ja analysoimassa sitä yhdessä projektin muiden jäsenten kanssa. Tutkimuksessa mitattiin kuinka ryhmiin osallistuvien seka masennuksen tunteet että toiminnat muuttuivat yhden vuoden aikana. Tutkimuksen tavoitteena oli sekä masennuksesta kärsivien naisten osallistuminen feministiseen toimintatutkimukseen että ammatillisesti ohjatun oma-apuryhmämenetelmän kehittäminen suomalaiseen mielenterveyspalveluun. Projektin tutkimustulosten mukaan siihen osallistuneet naiset voimaantuivat ymmärtämään itseään sekä saivat luottamusta sosiaaliisiin taitoihinsa. Pidemmällä aikavälillä naisten tunteet muuttuivat myönteisiksi, heidän suhteensa itseensä positiivisemmaksi ja he aktivoituivat fyysisesti. Lisäksi tutkimustulokset viittaavat siihen, että masennus voi johtua näkymättömästä, sukupuolisesti virittyneestä jännitteestä naisystävällisessä hyvinvointivaltiossa paljastaen ”hyvinvointimasennusoireilun”. Suomalaisen sosiologi Erik Allardtin hyvinvointitypologian - having, loving, being – mukaisesti nämä ryhmään osallistuvat naiset eivät koe puutteita niinkään materiaalisessa hyvinvoinnissa (having) vaan pikeminkin suhteiden, sosiaalisen ja emotionaalisen hyvinvoinnin ulottuvuuksilla (loving ja being). Se, että masentuneet naiset pystyvät tuomaan esille pitkään vaiennettuja kokemuksiaan, voi merkitä paljon heidän paranemisessaan ja voimaantumisessaan. Ammatillisesti ohjatut oma-apuryhmät ja naisystävälliset hoitokäytännöt mahdollistivat tämänkaltaisen paranemisprosessin alkamisen tutkimukseen osallistuneissa ryhmissä.

Current Care Guidelines for Cardiopulmonary Resuscitation : Implementation, skills and attitudes

Background: The national resuscitation guidelines were published in Finland in 2002 and are based on international guidelines published in 2000. The main goal of the national guidelines, available on the Internet free of charge, is early defibrillation by nurses in an institutional setting. Aim: To study possible changes in cardiopulmonary resuscitation (CPR) practices, especially concerning early defibrillation, nurses and students attitudes of guideline implementation and nurses and students ability to implement the guideline recommendations in clinical practices after publication of the Current Care (CC) guidelines for CPR 2002. Material and methods: CPR practices in Finnish health centres; especially concerning rapid defibrillation programmes, as well as the implementation of CC guidelines for CPR was studied in a mail survey to chief physicians of every health centre in Finland (Study I). The CPR skills using an automated external defibrillator (AED) were compared in a study including Objective stuctured clinical examination (OSCE) of resuscitation skills of nurses and nursing students in Finnish and Swedish hospital and institution (Studies II, III). Attitudes towards CPR-D and CPR guidelines among medical and nursing students and secondary hospital nurses were studied in surveys (Studies IV, V). The nurses receiving different CPR training were compared in a randomized trial including OSCE of CPR skills of nurses in Finnish Hospital (Study VI). Results: Two years after the publication, 40.7% of Finnish health centres used national resuscitation guidelines. The proportion of health centres having at least one AED (66%) and principle of nurse-performed defibrillation without the presence of a physician (42%) had increased. The CPR-D training was estimated to be insufficient regarding basic life support and advanced life support in the majority of health centres (Study I). CPR-D skills of nurses and nursing students in two specific Swedish and Finnish hospitals and institutions (Study II and III) were generally inadequate. The nurses performed better than the students and the Swedish nurses surpassed the Finnish ones. Geriatric nurses receiving traditional CPR-D training performed better than those receiving an Internet-based course but both groups failed to defibrillate within 60 s. Thus, the performance was not satisfactory even two weeks after traditional training (Study VI). Unlike the medical students, the nursing students did not feel competent to perform procedures recommended in the cardiopulmonary resuscitation guidelines including the defibrillation. However, the majority of nursing students felt confident about their ability to perform basic life support. The perceived ability to defibrillate correlated significantly with a positive attitude towards nurse-performed defibrillation and negatively with fear of damaging the patient s heart by defibrillation (Study IV). After the educational intervention, the nurses found their level of CPR-D capability more sufficient than before and felt more confident about their ability to perform defibrillation themselves. A negative attitude toward defibrillation correlated with perceived negative organisational attitudes toward cardiopulmonary resuscitation guidelines. After CPR-D education in the hospital, the majority (64%) of nurses hesitated to perform defibrillation because of anxiety and 27 % hesitated because of fear of injuring the patient. Also a negative personal attitude towards guidelines increased markedly after education (Study V). Conclusions: Although a significant change had occurred in resuscitation practices in primary health care after publication of national cardiopulmonary resuscitation guidelines the participants CPR-D skills were not adequate according to the CPR guidelines. The current way of teaching is unlikely to result in participants being able to perform adequate and rapid CPR-D. More information and more frequent training are needed to diminish anxiety concerning defibrillation. Negative beliefs and attitudes toward defibrillation affect the nursing students and nurses attitudes toward cardiopulmonary resuscitation guidelines. CPR-D education increased the participants self-confidence concerning CPR-D skills but it did not reduce their anxiety. AEDs have replaced the manual defibrillators in most institutions, but in spite of the modern devices the anxiety still exists. Basic education does not provide nursing students with adequate CPR-D skills. Thus, frequent training in the workplace has vital importance. This multi-professional program supported by the administration might provide better CPR-D skills. Distance learning alone cannot substitute for traditional small-group learning, tutored hands-on training is needed to learn practical CPR-D skills. Standardized testing would probably help controlling the quality of learning. Training of group-working skills might improve CPR performance.

Primordial Perturbations from a Self-interacting Curvaton

Inflation is a period of accelerated expansion in the very early universe, which has the appealing aspect that it can create primordial perturbations via quantum fluctuations. These primordial perturbations have been observed in the cosmic microwave background, and these perturbations also function as the seeds of all large-scale structure in the universe. Curvaton models are simple modifications of the standard inflationary paradigm, where inflation is driven by the energy density of the inflaton, but another field, the curvaton, is responsible for producing the primordial perturbations. The curvaton decays after inflation as ended, where the isocurvature perturbations of the curvaton are converted into adiabatic perturbations. Since the curvaton must decay, it must have some interactions. Additionally realistic curvaton models typically have some self-interactions. In this work we consider self-interacting curvaton models, where the self-interaction is a monomial in the potential, suppressed by the Planck scale, and thus the self-interaction is very weak. Nevertheless, since the self-interaction makes the equations of motion non-linear, it can modify the behaviour of the model very drastically. The most intriguing aspect of this behaviour is that the final properties of the perturbations become highly dependent on the initial values. Departures of Gaussian distribution are important observables of the primordial perturbations. Due to the non-linearity of the self-interacting curvaton model and its sensitivity to initial conditions, it can produce significant non-Gaussianity of the primordial perturbations. In this work we investigate the non-Gaussianity produced by the self-interacting curvaton, and demonstrate that the non-Gaussianity parameters do not obey the analytically derived approximate relations often cited in the literature. Furthermore we also consider a self-interacting curvaton with a mass in the TeV-scale. Motivated by realistic particle physics models such as the Minimally Supersymmetric Standard Model, we demonstrate that a curvaton model within the mass range can be responsible for the observed perturbations if it can decay late enough.

Self-Assembly of Biopolymers on Colloidal Particles via Hydrogen Bonding

Fabrication of multilayer microcapsules via layer-by-layer approach through hydrogen bonding has attracted enormous interest due to its strong response to pH. In this communication, we have prepared hydrogen-bonded multilayer microcapsule without using any cross-linking agent by using DNA base pair (adenine and thymine) modified biocompatible polymers. The growth of the self-assembly on colloidal (melamine formaldehyde: MF) particles has been monitored with zeta potential measurement. The capsules were obtained on dissolution of MF particles at 0.1N HCl. The capsules were characterized with scanning electron microscopy. Moreover, we have observed the salt induced microscopic change in self-assembly of this system on the surface of colloidal particles.

A Dynamic Migration Model for self-adaptive Genetic Algorithms

In this paper, we propose a self Adaptive Migration Model for Genetic Algorithms, where parameters of population size, the number of points of crossover and mutation rate for each population are fixed adaptively. Further, the migration of individuals between populations is decided dynamically. This paper gives a mathematical schema analysis of the method stating and showing that the algorithm exploits previously discovered knowledge for a more focused and concentrated search of heuristically high yielding regions while simultaneously performing a highly explorative search on the other regions of the search space. The effective performance of the algorithm is then shown using standard testbed functions, when compared with Island model GA(IGA) and Simple GA(SGA).

Propagation of a spherical shock in an inhomogeneous self-gravitating or nongravitating system

The propagation of a shock wave of finite strength due to an explosion into inhomogeneous nongravitating and self-gravitating systems has been considered, using similarity principles, supposing that the density varies as an inverse power of distance from the centre of explosion. A large number of systems, characterised by different density exponents and different adiabatic coefficients of the gas have been considered for different shock strengths. The numerical integration from the shock inward has been continued to the surface of singularity where density tends to infinity and which acts like a piston in the self-gravitating case and to the surface where the velocity gradient tends to infinity in the nongravitating case. The effect of variation of shock strength, density exponent and adiabatic coefficient on the location of these singularities and on the distribution of flow parameters behind the shock has been studied. The initial energy of the system and the manner of release of the explosion energy influence strongly the flow behind the shock. The results have been graphically depicted.

Self-regularized pseudo time-marching schemes for structural system identification with static measurements

We explore the application of pseudo time marching schemes, involving either deterministic integration or stochastic filtering, to solve the inverse problem of parameter identification of large dimensional structural systems from partial and noisy measurements of strictly static response. Solutions of such non-linear inverse problems could provide useful local stiffness variations and do not have to confront modeling uncertainties in damping, an important, yet inadequately understood, aspect in dynamic system identification problems. The usual method of least-square solution is through a regularized Gauss-Newton method (GNM) whose results are known to be sensitively dependent on the regularization parameter and data noise intensity. Finite time,recursive integration of the pseudo-dynamical GNM (PD-GNM) update equation addresses the major numerical difficulty associated with the near-zero singular values of the linearized operator and gives results that are not sensitive to the time step of integration. Therefore, we also propose a pseudo-dynamic stochastic filtering approach for the same problem using a parsimonious representation of states and specifically solve the linearized filtering equations through a pseudo-dynamic ensemble Kalman filter (PD-EnKF). For multiple sets of measurements involving various load cases, we expedite the speed of thePD-EnKF by proposing an inner iteration within every time step. Results using the pseudo-dynamic strategy obtained through PD-EnKF and recursive integration are compared with those from the conventional GNM, which prove that the PD-EnKF is the best performer showing little sensitivity to process noise covariance and yielding reconstructions with less artifacts even when the ensemble size is small.

Self-regularized pseudo time-marching schemes for structural system identification with static measurements

We explore the application of pseudo time marching schemes, involving either deterministic integration or stochastic filtering, to solve the inverse problem of parameter identification of large dimensional structural systems from partial and noisy measurements of strictly static response. Solutions of such non-linear inverse problems could provide useful local stiffness variations and do not have to confront modeling uncertainties in damping, an important, yet inadequately understood, aspect in dynamic system identification problems. The usual method of least-square solution is through a regularized Gauss-Newton method (GNM) whose results are known to be sensitively dependent on the regularization parameter and data noise intensity. Finite time, recursive integration of the pseudo-dynamical GNM (PD-GNM) update equation addresses the major numerical difficulty associated with the near-zero singular values of the linearized operator and gives results that are not sensitive to the time step of integration. Therefore, we also propose a pseudo-dynamic stochastic filtering approach for the same problem using a parsimonious representation of states and specifically solve the linearized filtering equations through apseudo-dynamic ensemble Kalman filter (PD-EnKF). For multiple sets ofmeasurements involving various load cases, we expedite the speed of the PD-EnKF by proposing an inner iteration within every time step. Results using the pseudo-dynamic strategy obtained through PD-EnKF and recursive integration are compared with those from the conventional GNM, which prove that the PD-EnKF is the best performer showing little sensitivity to process noise covariance and yielding reconstructions with less artifacts even when the ensemble size is small. Copyright (C) 2009 John Wiley & Sons, Ltd.

Extended self-similarity works for the Burgers equation and why

Extended self-similarity (ESS), a procedure that remarkably extends the range of scaling for structure functions in Navier-Stokes turbulence and thus allows improved determination of intermittency exponents, has never been fully explained. We show that ESS applies to Burgers turbulence at high Reynolds numbers and we give the theoretical explanation of the numerically observed improved scaling at both the IR and UV end, in total a gain of about three quarters of a decade: there is a reduction of subdominant contributions to scaling when going from the standard structure function representation to the ESS representation. We conjecture that a similar situation holds for three-dimensional incompressible turbulence and suggest ways of capturing subdominant contributions to scaling.

Instability of the self-similar flow into a cavity

In this paper we have investigated the instability of the self-similar flow behind the boundary of a collapsing cavity. The similarity solutions for the flow into a cavity in a fluid obeying a gas law p = Kργ, K = constant and 7 ≥ γ > 1 has been solved by Hunter, who finds that for the same value of γ there are two self-similar flows, one with accelerating cavity boundary and other with constant velocity cavity boundary. We find here that the first of these two flows is unstable. We arrive at this result only by studying the propagation of disturbances in the neighbourhood of the singular point.

On self-interacting oligoribonucleotides. I. Absorption and optical rotatory dispersion of 2′-5′- and 3′-5′-oligoguanylic acids

A series of 2′-5′-oligoguanylic acids are prepared by reacting G(cyclic)p with takadiastase T1 ribonuclease and separating the products chromatographically. The 3′-5′-oligoguanylic acids are obtained by separating the products of alkaline degradation of 3′-5′-poly(G). The optical rotatory dispersion and hypochromism of both 2′-5′- and 3′-5′-oligoguanylic acids are studied at two different pH. The optical rotatory dispersion spectrum of 2′-5′-GpG is significantly different from that of 3′-5′-GpG. The magnitude of rotation of the long-wavelength peak of 2′-5′-GpG is larger than that of 3′-5′-GpG. This finding contradicts the explanation that the extra stability and more intense circular dichroism band of other 3′-5′-dinucleoside monophosphates is due to H-bond formation between 2′-OH and either the base or the phosphate oxygen. The end phosphate group has a marked effect on the spectrum of GpG between 230 and 250 mμ. In addition the optical rotatory dispersion spectra of 2′-5′ exhibit strong pH, temperature, and solvent dependence between 230 and 250 mμ. ΔH and AS for order ⇌ disorder transition is estimated to be 9.7 kcal/mole and 35.2 eu, respectively. The optical rotatory dispersion spectra of guanine-rich oligoribonucleotides, GpGpC, GpGpU, GpGpGpC, and GpGpGpU are compared to the calculated optical rotatory dispersion from the semiempirical expression of Cantor and Tinoco, using measured optical rotatory dispersion of dimers. Contrary to previous studies, agreement is found not at all satisfactory. However, optical rotatory dispersion of 3′-5′-GpGpGpC and GpGpGpU can be estimated from the semiempirical expression, if a next-nearest interaction parameter is introduced empirically. Such interaction parameter can be calculated from the measured properties of trinucleotide sequences like GpGpG, GpGpC, and GpGpU, assuming that only the nearest-neighbor interaction is important. The optical rotatory dispersion of single-stranded poly(G) is also predicted. The importance of syn-anti equilibrium and next-nearest-neighbor interaction in oligoguanylic acids is suggested as a probable explanation.