Controlling the Chimera Form in the Leaky Integrate-and-Fire Model.

We study the influence of broken connectivity and frequency disorder in systems of coupled neuronal oscillators. Under nonlocal coupling, systems of nonlinear oscillators, such as Kuramoto, FitzHugh-Nagumo, or integrate-and-fire oscillators, demonstrate nontrivial synchronization patterns. One of these patterns is the "chimera state," which consists of coexisting coherent and incoherent domains. In networks of biological neurons, the connectivity is not always perfect, but might be locally broken or interrupted due to pathologies, neuron degenerative disorders, or accidents. Our simulations show that destructed connectivity drastically affects synchronization, driving the coherent parts of the chimera state to cover symmetrically the region where the anomaly is located. The network synchronization decreases with the size of the destructed region as evidenced by the Kuramoto synchronization index. To the contrary, when keeping the connectivity of all nodes intact, altering the frequency in a block of oscillators drives the incoherent part of the chimera state toward the anomaly. This work is in line with recent dynamical approaches aiming to locate anomalies in the structure of brain networks, in particular when the anomalies have small, difficult-to-detect sizes.

[Natural Childbirth after the Previous Caesarian Section is a Solved Problem].

Тhe rapid increase in the frequency of сesarian section (CS) observed in recent years (up to 60% in some countries) is alarming and reduces the reproductive potential of the population. The operated uterus remains the main indication for CS (up to 40%). This is the factor which may allow reducing the frequency of the CS by subsequent delivering through the birth canal. A comparative analysis of maternal and neonatal outcomes enabled the authors to develop a two-stage delivery technology for patients with a caesarean scar, including the usage of the programmed delivery method. The presented algorithm confirmed the validity of vaginal delivery in such patients, and reduced the number of complications up to 4 times. Neonatal morbidity in children born through the birth canal in such patients was comparable to physiological birth.

Successful network inference from time-series data using mutual information rate.

This work uses an information-based methodology to infer the connectivity of complex systems from observed time-series data. We first derive analytically an expression for the Mutual Information Rate (MIR), namely, the amount of information exchanged per unit of time, that can be used to estimate the MIR between two finite-length low-resolution noisy time-series, and then apply it after a proper normalization for the identification of the connectivity structure of small networks of interacting dynamical systems. In particular, we show that our methodology successfully infers the connectivity for heterogeneous networks, different time-series lengths or coupling strengths, and even in the presence of additive noise. Finally, we show that our methodology based on MIR successfully infers the connectivity of networks composed of nodes with different time-scale dynamics, where inference based on Mutual Information fails.

Complex statistics and diffusion in nonlinear disordered particle chains.

We investigate dynamically and statistically diffusive motion in a Klein-Gordon particle chain in the presence of disorder. In particular, we examine a low energy (subdiffusive) and a higher energy (self-trapping) case and verify that subdiffusive spreading is always observed. We then carry out a statistical analysis of the motion, in both cases, in the sense of the Central Limit Theorem and present evidence of different chaos behaviors, for various groups of particles. Integrating the equations of motion for times as long as 10(9), our probability distribution functions always tend to Gaussians and show that the dynamics does not relax onto a quasi-periodic Kolmogorov-Arnold-Moser torus and that diffusion continues to spread chaotically for arbitrarily long times.

Validation of radiographic visibility of root pulp in mandibular first, second and third molars in the prediction of 21 years in a sample of south Indian population: A digital panoramic radiographic study.

This study examines the radiographic visibility of root pulp (RPV) in lower first, second and third molars to validate the completion of 21 years. RPV in all lower three molars of both sides was assessed using a sample of 930 orthopantomograms of individuals aged between 15 and 30. The scoring of RPV was done using the Olze et al. four-stage classification (Int J Legal Med 124(3):183-186, 2010). Cut-off values were determined for each molar using the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC). The selected cut-off values were stage 3 for the first molar, stage 2 for the second molar and stage 1 for the third molar. For lower first molar, the AUC was 0.702, and the sensitivity, specificity and posttest probability (PTP) were 60.1%, 98.8% and 98.1% in males, and 64.5%, 99.1% and 98.6% in females. For lower second molar, the AUC was 0.828, and the sensitivity, specificity and PTP were 75.5%, 97% and 96.2% in males, and 74.4%, 96.3% and 95.3% in females. For the lower third molar, the AUC was 0.906; the sensitivity was 74.1% and 64.4% in males and females, while specificity and PTP were 100% in both sexes. The accuracy of predictions for the completion of 21 years was high. However, the greater percentage of false negatives and inapplicability of this method in one-third of lower-third molars have been recommended for using this method in conjunction with other dental or skeletal methods.

Polyelectrolyte-assisted formation of molecular nanoparticles exhibiting strongly enhanced fluorescence.

A polyelectrolyte-assisted reprecipitation method is developed to fabricate nanoparticles of highly soluble molecules. The approach is demonstrated by using a zwitterionic diaminodicyanoquinodimethane molecule bearing remote ammonium functionalities with high solubility in water as well as organic solvents. Nanoparticles are prepared by injecting aqueous solutions of this compound containing an optimum concentration of sodium poly(styrenesulfonate) into methanol. The strong fluorescence exhibited by the compound in the aggregated state is reflected in the enhanced fluorescence of the polyelectrolyte complex in water. The nanoparticles formed in the colloidal state manifest even stronger fluorescence, which leads to an overall enhancement by about 90 times relative to aqueous solutions of the pure compound. The conditions for achieving the emission enhancement are optimized and a model for the molecular-level interactions and aggregation effects is developed through a range of spectroscopy, microscopy, and calorimetry investigations and control experiments.

Efficient Bioimaging with Diaminodicyanoquinodimethanes: Selective Imaging of Epidermal and Stomatal Cells and Insight into the Molecular Level Interactions.

The enhanced fluorescence emission of diaminodicyanoquinodimethanes (DADQs) in rigid and aggregated states holds great promise for bioimaging applications. This is demonstrated through their efficient application in epidermal and stomatal imaging with selective staining of cell walls and nuclei. Major advantages include the small quantities (a few nmols) of the fluorophore required, choice of DADQs soluble in water and organic solvents, and quick staining of the specimen in buffer-free state and in buffer medium. The molecular level interactions that enable staining are unraveled through isothermal calorimetry, infra-red spectroscopy and microscopy with energy dispersive X-ray spectroscopy analysis. It is proposed that DADQs with ionic or H-bonding functionalities bind to the polygalacturonic acid moieties in the epidermal layer; the former can bind also to nucleic acid polyanions. Fluorescence experiments explain the emission enhancement that enables the efficient imaging. DADQs are easy to synthesize, non-cytotoxic, and thermally, chemically and photo-stable, requiring no special storage conditions; preliminary experiments point to their potential utility in imaging different classes of cells.

Epidemiologic characteristics of hypertension in the civilians of Kosovo after the war.

34th Greek regimen, which was part of the NATO forces, provided medical services to the civilians of Kosovo. We studied epidemiologic data in the population of Kosovo regarding hypertension in order to determine the prevalence and characteristics of hypertension. 830 patients (281 - 33.86% male, 62 +/- 26 yrs and 549 - 66.14% female, 49 +/- 28 yrs) were examined for different diseases. We identified 254 (30.6%) patients with hypertension (188 female and 66 male). According to the international criteria used for the classification of the severity of hypertension, more than half of the patients (51.2%) had severe hypertension, 31.5% modest and 17.3% mild. Statistically significant relation between the severity of hypertension and age or sex was not found out. Increased BMI as well as the presence of proteinuria and rheumatic diseases were significantly related to the severity of the hypertension while the coexistent heart disease, diabetes mellitus and chronic obstructive pulmonary disease (COPD) wasn't. The use of non-steroid anti-inflammatory agents (NSAIDs) was related to the severity of hypertension with a borderline significance. 31.4% of the patients were on treatment with NSAIDs and/or cortisone because of rheumatic disease or obstructive pulmonary disease. Overfunction of the sympathetic system was present in 62.99%. The mean heart rate was greater in women (84/min) than in men (72/min). 28.35% of the patients had secondary hypertension, including the patients on a drug that can elevate the blood pressure and patients with increased activity of the sympathetic nervous system. So, 8.6% of the patients had usual causes of secondary hypertension and 19.6% hypertension secondary related to the use of NSAIDs or cortisone, or due to the increased activity of the sympathetic nervous system. Antihypertensive treatment was started in 248 patients, i.e. in all of them except the ones already on treatment having their blood pressure well controlled. For antihypertensive treatment beta-blockers or central adrenergic inhibitors either as monotherapy or in combination with other agents were used most frequently combined with diuretics and Ca antagonists and ACE inhibitors. In conclusion the diagnosis and treatment of hypertension in the population of Kosovo during the post war period had certain particularities.

Effects of Oestradiol-17 ß on the Ovaries of the Starfish Asterias rubens.

Oocyte diameters and their frequency distribution, and various other data determined for the oestradiol-17 ß treated female specimens of Asterias rubens proved to be significantly different from those for the control animals. The maturation index of the treated animals is 2.4, that of the control animals 1.4. Since the treated animals show a greater heterogeneity in development than the control animals, and because the diameter of the smallest oocytes is the same for both treated and control animals, a threshold size of the oocytes may be required before oocyte growth can be stimulated by oestradiol-17ß, and before substances originating in the pyloric caeca are incorporated into the oocytes. Oestradiol-17ß treatment caused a tenfold increase of the oestrone level in the ovaries, whereas a non-significant increase was observed in the pyloric caeca. This may indicate that in vivo oestradiol-17ß is converted into oestrone in the ovaries but not in the pyloric caeca.

A comparative study of adduct formation between the anticancer ruthenium(III) compound HInd trans-[RuCl4(Ind)2] and serum proteins.

Formation of adducts between the antitumor ruthenium(III) complex [HInd]trans-[RuCl(4)(Ind)(2)] (KP1019) and the plasma proteins serum albumin and serum transferrin was investigated by UV-vis spectroscopy, for metal-to-protein ratios ranging from 1:1 to 5:1. In both cases, formation of tight metal-protein conjugates was observed. Similar spectroscopic features were observed for both albumin and transferrin derivatives implying a similar binding mode of the ruthenium species to these proteins. Surface histidines are the probable anchoring sites for the bound ruthenium(III) ions in line with previous crystallographic results. In order to assess the stability of the KP1019-protein adducts the influence of pH, reducing agents and chelators was analysed by UV-vis spectroscopy. Notably, there was no effect of addition of EDTA on the UV-vis spectra of the conjugates. The pH-stability was high in the pH range 5-8. Experiments with sodium ascorbate showed that there was just some alteration of selected bands. The implications of the present results are discussed in relation to the pharmacological behavior of this novel class of antitumor compounds.

Utility of ultrasonographic venous assessment prior to forearm arteriovenous fistula creation.

AIM: The purpose of this study was to evaluate the clinical utility of Doppler ultrasound (US) prior to native forearm arteriovenous fistula (AVF) creation. MATERIALS AND METHODS: US mapping was carried out pre-operatively to evaluate the major veins and arteries in the appropriate arm. One hundred and 6 patients were identified retrospectively over 2 years with complete clinical and US data. A failed fistula was defined as an inability to provide blood flow to meet adequacy targets by 6 months (urea reduction ratio > or = 65%). RESULTS: Twenty-nine patients (27.4%) had successful forearm AVFs. The mean minimum forearm cephalic vein diameter (CVD) was 2.51 +/- 0.14 and 2.23 +/- 0.06 mm in successful and failed fistulae, respectively (p = 0.04). This result was primarily due to differences observed in women. A receiver operator curve analysis showed that a cutpoint of 2.6 mm for minimum forearm CVD had the greatest predictive value with a likelihood ratio of 3.94 (95% CI: 1.97 - 7.84) for fistula failure. Multivariate logistic regression analysis determined that male gender and minimum forearm CVD were the only significant predictors for fistula success with odds ratios of 3.90 (95% CI: 1.30 - 11.68) and 2.31 (95% CI: 1.00 - 5.43), respectively. The study is limited by the possibility that US results in patients may have lead to an alternative type of access being attempted. CONCLUSIONS: US mapping prior to forearm AVF creation is of modest benefit. Only male gender and minimum forearm CVD were predictive of AVF success.

Cell proliferation and DNA fragmentation (apoptosis) on FNABs of breast invasive ductal carcinomas and their relationship to clinicopathological variables and prognosis.

The purpose of this study was to investigate cell proliferation and apoptosis in ductal breast invasive carcinomas and their relationship to prognosis. Fifty cases, from the same number of operable female patients, were diagnosed cytologically on FNA biopsies as invasive ductal breast carcinomas and confirmed histologically after oncectomy. In the same cases, to evaluate the cell proliferation and apoptosis, the MIB1 and the TUNEL method were used respectively. Furthermore the relationship between proliferative activity and apoptosis to other factors such as menopausal status, tumor size, axillary lymph node status and tumor grade was studied. Cell proliferation and apoptosis were found to be significantly related to the menopausal status of the patients (p < 0.001) and to the grade of the tumor (p < 0.01), while no significant relationship to axillary lymph node status and tumor size was found.

Lack of association between the C677T mutation in the 5,10-methylenetetrahydrofolate reductase gene and venous thromboembolism in Northwestern Greece.

BACKGROUND: Hyperhomocysteinemia has been associated with venous thrombosis. Under known and unknown conditions the C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene is accompanied by elevated levels of homocysteine. However, the relationship of this mutation with venous thromboembolism (VTE) remains controversial. The purpose of this study was to evaluate the association of the MTHFR mutation with VTE. METHODS: The presence of the C677T mutation in the MTHFR gene was investigated in a population of 176 consecutive patients with a history of venous thromboembolism and in a control group of 300 healthy subjects, using DNA analysis. RESULTS: The prevalence of homozygosity in the patient group was 13.6% and in healthy subjects 10%. The odds ratio for venous thromboembolism in the presence of the homozygous genotype (677TT) was 1.4 (95% confidence interval (C.I.), 0.8 to 2.5), which was not statistically significant. CONCLUSIONS: Homozygosity for the T677 allele of the MTHFR gene, although slightly more prevalent in patients compared to controls, has not been found in association with venous thromboembolism.

Prevalence of the G20210A prothrombin gene mutation in Northwestern Greece and association with venous thromboembolism.

AIM: The G20210A mutation of the prothrombin gene is a genetic risk factor for venous thromboembolism (VTE). Variability exists in the mutation prevalence in both normal individuals and VTE patients. The aim of this study was to determine the mutation prevalence in Northwestern Greece and evaluate its association with VTE. METHODS: Presence of the G20210A mutation was investigated using DNA analysis in 176 consecutive patients with a history of venous thrombosis or pulmonary embolism and in 300 healthy controls, all Caucasian residents of Northwestern Greece. RESULTS: The mutation was present 12 patients (6.8%) and 8 controls (2.7%). The odds ratio for presence of the mutation versus the normal genotype in VTE was 2.7 (95% CI: 1.1 to 6.7), which was statistically significant. The prevalence of the G20210A prothrombin gene mutation in Northwestern Greece is 2.7% (95% CI: 0.8% to 4.4%) with an allele frequency of 1.3% (95% CI: 0.4% to 2.3%). CONCLUSION: The G20210A mutation of the prothrombin gene is associated with VTE in the Caucasian residents of this geographic region.

['Proteomics': the mapping of all human proteins]. / 'Proteomics': het in kaart brengen van alle humane eiwitten.

The genomes of many organisms, including humans, are now largely known. In the wake of this there is a need to identify and measure all proteins that are encoded by the genome (proteomics). This need leads to turbulent developments in the area of analytical techniques, such as two-dimensional electrophoresis, mass spectrometry, and protein chips. The rapidity of advancements justifies the expectation that in the next 5-10 years it will indeed become possible to determine the proteome of an organism or its components such as plasma, serum, or tissues. In combination with information on initiation and progress of disease, proteomics will contribute to improving health and to better primary and secondary prevention.

Optical materials based on molecular nanoparticles.

A major part of contemporary nanomaterials research is focused on metal and semiconductor nanoparticles, constituted of extended lattices of atoms or ions. Molecular nanoparticles assembled from small molecules through non-covalent interactions are relatively less explored but equally fascinating materials. Their unique and versatile characteristics have attracted considerable attention in recent years, establishing their identity and status as a novel class of nanomaterials. Optical characteristics of molecular nanoparticles capture the essence of their nanoscale features and form the basis of a variety of applications. This review describes the advances made in the field of fabrication of molecular nanoparticles, the wide spectrum of their optical and nonlinear optical characteristics and explorations of the potential applications that exploit their unique optical attributes.