Connectivity Influences on Nonlinear Dynamics in Weakly-Synchronized Networks: Insights from Rössler Systems, Electronic Chaotic Oscillators, Model and Biological Neurons

Natural and engineered networks, such as interconnected neurons, ecological and social networks, coupled oscillators, wireless terminals and power loads, are characterized by an appreciable heterogeneity in the local connectivity around each node. For instance, in both elementary structures such as stars and complex graphs having scale-free topology, a minority of elements are linked to the rest of the network disproportionately strongly. While the effect of the arrangement of structural connections on the emergent synchronization pattern has been studied extensively, considerably less is known about its influence on the temporal dynamics unfolding within each node. Here, we present a comprehensive investigation across diverse simulated and experimental systems, encompassing star and complex networks of Rössler systems, coupled hysteresis-based electronic oscillators, microcircuits of leaky integrate-and-fire model neurons, and finally recordings from in-vitro cultures of spontaneously-growing neuronal networks. We systematically consider a range of dynamical measures, including the correlation dimension, nonlinear prediction error, permutation entropy, and other information-theoretical indices. The empirical evidence gathered reveals that under situations of weak synchronization, wherein rather than a collective behavior one observes significantly differentiated dynamics, denser connectivity tends to locally promote the emergence of stronger signatures of nonlinear dynamics. In deterministic systems, transition to chaos and generation of higher-dimensional signals were observed; however, when the coupling is stronger, this relationship may be lost or even inverted. In systems with a strong stochastic component, the generation of more temporally-organized activity could be induced. These observations have many potential implications across diverse fields of basic and applied science, for example, in the design of distributed sensing systems based on wireless coupled oscillators, in network identification and control, as well as in the interpretation of neuroscientific and other dynamical data

Design of Electromagnetic Pulse Crimp Torque Joints

Electromagnetic pulse crimping of form fit joints was investigated using tubes with a diameter of 50 mm and a wall thickness of 1,5 mm, in the aluminium alloy EN AW-6060. The tubes were crimped onto steel internal parts, which were designed to bear torsional loads. Grooved, knurl rolled and knurl cut internal workpieces were used. To assess the torque strength of the connections, a torque test set-up was designed and built. In a first test series, grooved internal parts were used. The influence of the internal workpiece design and the energy level on the torque resistance was investigated. Related to the geometry of the internal workpiece, the following parameters were varied: the groove depth, the groove width, the edge radius and the number of grooves. In a second test series, knurl rolled and knurl cut internal workpieces were used. For the joints with a knurl rolled internal part, the influence of the knurl pattern, defined by the pitch, was investigated. For the connections with a knurl cut internal part, the influence of the energy level was studied. The different joint failure mechanisms were determined

Breathing 100% oxygen during water immersion improves postimmersion cardiovascular responses to orthostatic stress

Physiological compensation to postural stress is weakened after long-duration water immersion (WI), thus predisposing individuals to orthostatic intolerance. This study was conducted to compare hemodynamic responses to postural stress following exposure to WI alone (Air WI), hyperbaric oxygen alone in a hyperbaric chamber (O2HC), and WI combined with hyperbaric oxygen (O2WI), all at a depth of 1.35 ATA, and to determine whether hyperbaric oxygen is protective of orthostatic tolerance. Thirty-two healthy men underwent up to 15 min of 70° head-up tilt (HUT) testing before and after a single 6-h resting exposure to Air WI (N = 10), O2HC (N = 12), or O2WI (N = 10). Heart rate (HR), blood pressure (BP), cardiac output (Q), stroke volume (SV), forearm blood flow (FBF), and systemic and forearm vascular resistance (SVR and FVR) were measured. Although all subjects completed HUT before Air WI, three subjects reached presyncope after Air WI exposure at 10.4, 9.4, and 6.9 min. HUT time did not change after O2WI or O2HC exposures. Compared to preexposure responses, HR increased (+10 and +17%) and systolic BP (-13 and -8%), and SV (-16 and -23%) decreased during HUT after Air WI and O2WI, respectively. In contrast, HR and SV did not change, and systolic (+5%) and diastolic BP (+10%) increased after O2HC. Q decreased (-13 and -7%) and SVR increased (+12 and +20%) after O2WI and O2HC, respectively, whereas SVR decreased (-9%) after Air WI. Opposite patterns were evident following Air WI and O2HC for FBF (-26 and +52%) and FVR (+28 and -30%). Therefore, breathing hyperbaric oxygen during WI may enhance post-WI cardiovascular compensatory responses to orthostatic stress

Bizneset e vogla familjare garant i zhvillimit ekonomik e social

Integrimi global ekonomik si proces gjithnjë e më shumë po ka ndikim edhe në politikat nacionale të zhvillimit, ndaj si i tillë është jashtëzakonisht vështir që të kontrollohet me aplikimin e metodave dhe instrumenteve tradicionale të zhvillimit ekonomik. Kjo mbase vështirëson që në vitet në vijim, të planifikohen qëllime të caktuara ekonomike në nivel shteti. Të gjitha ndërmarrjet në botë, të mëdha apo të vogla, familjare dhe jo familjare, publike apo jo publike, të zhvilluara dhe të pa zhvilluara, po përballen me një sërë pyetjesh të cilat kanë të bëjnë me ardhmërinë dhe perspektivën e tyre, respektivisht vije në pikëpyetje ekzistenca e tyre në situata të paparapara turbulente për rrethinën. Çfarë do të jenë nevojat e tregut, çfarë synon konkurrenca, a po lëkunden qëndrimet e blerësve, kah pretendon përparimi i teknikës dhe teknologjisë, çfarë me zhvillimin e prodhimeve të reja, a ka mundësi të sigurimit të resurseve të nevojshme, kah udhëzon globalizimi i biznesit,cilat nevoja duhet përdorur për arritjen e efikasitetit, efektiviteti dhe inovacionet, etj… të gjitha këto pyetje u adresohen çdo ditë ndërmarrjeve – pa marrë parasysh nëse ato janë në pronësi të familjes apo nuk janë të tilla. Ajo çka ndërmarrjet familjare i bënë të veçanta dhe që i dallon nga ndërmarrjet e tjera që nuk janë në pronësi apo kontroll të familjes, paraqet diversitetin e interesit familjar dhe interesit të ndërmarrjes në sistemin e unik të biznesit familjar. Pronarët e kompanive familjare në të gjithë botën ndajnë filozofinë dhe vlerat e njëjta, ata mendojnë në perspektivë, kapitali i tyre është durimi dhe zelli, interesohen për bashkësinë ku veprojnë dhe punojnë ashtu që kompaninë në gjendjen më të mirë të mundshme t’ua lënë trashëgimtarëve të tyre. Modeli i biznesit të kompanive familjare është tejet inovativ dhe largpamës, kërkon në realizim më të mirë, krijon më shumë vlera, ruan vendet e punës, përkundër rënieve dhe recesioneve ciklike. Zhvillimi i ndërmarrjeve të vogla dhe të mesme familjare, paraqet rrugën më të shpejtë dhe më të lirë të zhvillimit të ekonomive kombëtare. NVM janë shtyllat kurrizore të zhvillimit ekonomik të shteteve në tranzicion dhe përkrah rolit të madh që kanë në punësim ato janë mjaft domethënëse për demokratizimin e shoqërisë

Bayesian sequential integration within a preclinical pharmacokinetic and pharmacodynamic modeling framework:Lessons learned

The present manuscript aims to discuss the implications of sequential knowledge integration of small preclinical trials in a Bayesian pharmacokinetic and pharmacodynamic (PK-PD) framework. While, at first sight, a Bayesian PK-PD framework seems to be a natural framework to allow for sequential knowledge integration, the scope of this paper is to highlight some often-overlooked challenges while at the same time providing some guidances in the many and overwhelming choices that need to be made. Challenges as well as opportunities will be discussed that are related to the impact of (1) the prior specification, (2) the choice of random effects, (3) the type of sequential integration method. In addition, it will be shown how the success of a sequential integration strategy is highly dependent on a carefully chosen experimental design when small trials are analyzed

Stellar parameters of Be stars observed with X-shooter

Aims. The X-shooter archive of several thousand telluric star spectra was skimmed for Be and Be-shell stars to derive the stellar fundamental parameters and statistical properties, in particular for the less investigated late type Be stars, and the extension of the Be phenomenon into early A stars. Methods. An adapted version of the BCD method is used, utilizing the Balmer discontinuity parameters to determine effective temperature and surface gravity. This method is optimally suited for late B stars. The projected rotational velocity was obtained by profile fitting to the Mg ii lines of the targets, and the spectra were inspected visually for the presence of peculiar features such as the infrared Ca ii triplet or the presence of a double Balmer discontinuity. The Balmer line equivalent widths were measured, but due to uncertainties in determining the photospheric contribution are useful only in a subsample of Be stars for determining the pure emission contribution. Results. A total of 78 Be stars, mostly late type ones, were identified in the X-shooter telluric standard star archive, out of which 48 had not been reported before. The general trend of late type Be stars having more tenuous disks and being less variable than early type ones is confirmed. The relatively large number (48) of relatively bright (V > 8.5) additional Be stars casts some doubt on the statistics of late type Be stars; they are more common than currently thought: The Be/B star fraction may not strongly depend on spectral subtype.Comment: Accepted for publication in A&

Re-evaluating diabetic papillopathy using optical coherence tomography and inner retinal sublayer analysis.

BACKGROUND/OBJECTIVES: To re-evaluate diabetic papillopathy using optical coherence tomography (OCT) for quantitative analysis of the peripapillary retinal nerve fibre layer (pRNFL), macular ganglion cell layer (mGCL) and inner nuclear layer (mINL) thickness. SUBJECTS/METHODS: In this retrospective observational case series between June 2008 and July 2019 at Moorfields Eye hospital, 24 eyes of 22 patients with diabetes and optic disc swelling with confirmed diagnosis of NAION or diabetic papillopathy by neuro-ophthalmological assessment were included for evaluation of the pRNFL, mGCL and mINL thicknesses after resolution of optic disc swelling. RESULTS: The mean age of included patients was 56.5 (standard deviation (SD) ± 14.85) years with a mean follow-up duration of 216 days. Thinning of pRNFL (mean: 66.26, SD ± 31.80 µm) and mGCL (mean volume: 0.27 mm3, SD ± 0.09) were observed in either group during follow-up, the mINL volume showed no thinning with 0.39 ± 0.05 mm3. The mean decrease in visual acuity was 4.13 (SD ± 14.27) ETDRS letters with a strong correlation between mGCL thickness and visual acuity (rho 0.74, p < 0.001). CONCLUSION: After resolution of acute optic disc swelling, atrophy of pRNFL and mGCL became apparent in all cases of diabetic papillopathy and diabetic NAION, with preservation of mINL volumes. Analysis of OCT did not provide a clear diagnostic distinction between both entities. We suggest a diagnostic overlay with the degree of pRNFL and mGCL atrophy of prognostic relevance for poor visual acuity independent of the semantics of terminology

Ten-year survival trends of neovascular age-related macular degeneration at first presentation

BACKGROUND: To describe 10-year trends in visual outcomes, anatomical outcomes and treatment burden of patients receiving antivascular endothelial growth factor (anti-VEGF) therapy for neovascular age-related macular degeneration (nAMD). METHODS: Retrospective cohort study of treatment-naïve, first-affected eyes with nAMD started on ranibizumab before January 1, 2009. The primary outcome was time to best-corrected visual acuity (BCVA) falling ≤35 ETDRS letters after initiating anti-VEGF therapy. Secondary outcomes included time to BCVA reaching ≥70 letters, proportion of eyes with BCVA ≥70 and ≤35 letters in 10 years, mean trend of BCVA and central retinal thickness over 10 years, and mean number of injections. RESULTS: For our cohort of 103 patients, Kaplan-Meier analyses demonstrated median time to BCVA reaching ≤35 and ≥70 letters were 37.8 (95% CI 22.2 to 65.1) and 8.3 (95% CI 4.8 to 20.9) months after commencing anti-VEGF therapy, respectively. At the final follow-up, BCVA was ≤35 letters and ≥70 letters in 41.1% and 21%, respectively, in first-affected eyes, while this was the case for 5.4% and 48.2%, respectively, in a patient's better-seeing eye. Mean injection number was 37.0±24.2 per eye and 53.6±30.1 at patient level (63.1% of patients required injections in both eyes). CONCLUSIONS: The chronicity of nAMD disease and its management highlights the importance of long-term visual prognosis. Our analyses suggest that one in five patients will retain good vision (BCVA ≥70 ETDRS letters) in the first-affected eye at 10 years after starting anti-VEGF treatment; yet, one in two patients will have good vision in their better-seeing eye. Moreover, our data suggest that early treatment of nAMD is associated with better visual outcomes