Revealing dynamics, communities and criticality from data

Complex systems such as ecological communities and neuron networks are essential parts of our everyday lives. These systems are composed of units which interact through intricate networks. The ability to predict sudden changes in the dynamics of these networks, known as critical transitions, from data is important to avert disastrous consequences of major disruptions. Predicting such changes is a major challenge as it requires forecasting the behaviour for parameter ranges for which no data on the system is available. We address this issue for networks with weak individual interactions and chaotic local dynamics. We do this by building a model network, termed an {}, consisting of the underlying local dynamics and a statistical description of their interactions. We show that behaviour of such networks can be decomposed in terms of an emergent deterministic component and a {} term. Traditionally, such fluctuations are filtered out. However, as we show, they are key to accessing the interaction structure. { We illustrate this approach on synthetic time-series of realistic neuronal interaction networks of the cat cerebral cortex and on experimental multivariate data of optoelectronic oscillators. } We reconstruct the community structure by analysing the stochastic fluctuations generated by the network and predict critical transitions for coupling parameters outside the observed range

Local differences of the position of the mental foramen

The mental foramen has been reported to vary in position in different ethnic groups. Repeated failures during injections and operative procedures involving the mental foramen suggest the presence of local differences in a given population. The aim of the present study was to investigate possible local differences of the mental foramen in Eastern Anatolian individuals in the Turkish population. The present investigation is based on the examination of 70 adult mandibles. The study consisted of three measurements, to include the relations of the mental foramen to the following: 1) the lower teeth; 2) the body of mandible; 3) the mandibular symphysis and posterior border of the ramus of the mandible. The most common position of the foramen was in line with the longitudinal axis of the second premolar tooth (relation IV), at the midpoint of the mandibular body height and at 1/3.5 of the distance from the mandibular symphysis to the posterior border of the ramus. Local differences of the mental foramen may occur in a population. Prior to surgery knowledge of the most common location of the foramen peculiar to a local population may enable effective mental block anaesthesia to be provided. (Folia Morphol 2008; 67: 32-35)

Determination of Antioxidant and Anti-Melanogenesis Activities of Indonesian Lai, Durio kutejensis [Bombacaceae (Hassk) Becc] Fruit Extract

Purpose: To investigate the antioxidant and anti-melanogenesis activities of Durio kutejensis [Bombacaceae (Hassk.) Becc] fruit extract.Methods: The fruit flesh of D. kutejensis was extracted successively with n-hexane, ethyl acetate/EtOAc, and ethanol/EtOH at room temperature repeatedly. The extracts were concentrated in vacuo to yield their residues. Antioxidant properties were analyzed by 2,2'-azino-bis(3- ethylbenzothiazoline-6-sulphonic acid) (ABTS, superoxide dismutase (SOD)-like activity, 2,2-diphenyl-1- picrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) while anti-melanogensis activity was evaluated by tyrosinase enzyme activity and B16 melanoma cell assays (melanin inhibition and cytotoxicity).Results: The extract (200 μg/mL) showed melanin inhibition by inhibiting melanin formation in B16 melanoma cell by 47 % without cytotoxicity but did not inhibit tyrosinase enzyme activity. The extract (1 - 1000 μg/mL) also exhibited some level of antioxidant activity including ORAC (0.04 ± 0.00 μmol TE/mg at 950 μg/mL), ABTS (1.0 ± 0.2 % at 100.8 μg/mL), SOD (IC50, 76.00 ± 14.6 μg/mL, and DPPH (21.5 ± 0.7 % at 97.39 μg/mL extract concentration).Conclusion: The fruit extract of Durio kutejensis has antioxidant properties with a potential for treating hyperpigmentation and for use as a skin-lightening agent.Keywords: Durio kutejensis, Antioxidant, Anti-melanogenesis, B16 Melanoma cell Hyperpigmentation, Skin-lightening agen

Dehydration of potato slices following brief dipping in osmotic solutions: effect of conditions and understanding the mechanism of water loss

A novel variant of osmotic dehydration, named here as post-dipping dehydration – where a material is dipped in a salt or sugar solution for a very short time followed by simple exposure to ambient conditions was explored with the aim of lowering water content of potato slices but at the same time not gain a high level of sugar/salt. The rate of water loss, which was rapid initially, was found to approach equilibrium. This paper also explored whether the water loss process could subsequently be kick started once again, by employing a multi-stage process, where each stage consisted of osmotic solution dipping followed by ambient holding of the potato slices that had reached equilibrium in the earlier stage. Water loss values comparable to conventional osmotic dehydration could be achieved thus, but with significantly lower overall solid gain (less than 50%) – which can potentially yield a significantly healthy product option

A novel treatment strategy for preterm birth: Intra-vaginal progesterone-loaded fibrous patches

Progesterone-loaded poly(lactic) acid fibrous polymeric patches were produced using electrospinning and pressurized gyration for intra-vaginal application to prevent preterm birth. The patches were intravaginally inserted into rats in the final week of their pregnancy, equivalent to the third trimester of human pregnancy. Maintenance tocolysis with progesterone-loaded patches was elucidated by recording the contractile response of uterine smooth muscle to noradrenaline in pregnant rats. Both progesterone-loaded patches indicated similar results from release and thermal studies, however, patches obtained by electrospinning had smaller average diameters and more uniform dispersion compared to pressurized gyration. Patches obtained by pressurized gyration had better results in production yield and tensile strength than electrospinning; thereby pressurized gyration is better suited for scaled-up production. The patches did not affect cell attachment, viability, and proliferation on Vero cells negatively. Consequently, progesterone-loaded patches are a novel and successful treatment strategy for preventing preterm birth

Hydrocarbon productivities in different Botryococcus strains: comparative methods in product quantification

Six different strains of the green microalgae Botryococcus belonging to the A-race or B-race, accumulating alkadiene or botryococcene hydrocarbons, respectively, were compared for biomass and hydrocarbon productivities. Biomass productivity was assessed gravimetrically upon strain growth in the laboratory under defined conditions. Hydrocarbon productivities were measured by three different and independent experimental approaches, including density equilibrium of the intact cells and micro-colonies, spectrophotometric analysis of hydrocarbon extracts, and gravimetric quantitation of eluted hydrocarbons. All three hydrocarbon-quantitation methods yielded similar results for each of the strains examined. The B-race microalgae Botryococcus braunii var. Showa and Kawaguchi-1 constitutively accumulated botryococcene hydrocarbons equivalent to 30% and 20%, respectively, of their overall biomass. The A-race microalgae Botryococcus braunii, varieties Yamanaka, UTEX 2441 and UTEX LB572 constitutively accumulated alkadiene hydrocarbons ranging from 14% to 13% and 10% of their overall biomass, respectively. Botryococcus sudeticus (UTEX 2629), a morphologically different green microalga, had the lowest hydrocarbon accumulation, equal to about 3% of its overall biomass. Results validate the density equilibrium and spectrophotometric analysis methods in the quantitation of botryococcene-type hydrocarbons. These analytical advances will serve in the screening and selection of B. braunii and of other microalgae in efforts to identify those having a high hydrocarbon content for use in commercial applications

Temporal variation in out-of-hospital cardiac arrest occurrence in individuals with or without diabetes

Objective: Out-of-hospital cardiac arrest (OHCA) occurrence has been shown to exhibit a circadian rhythm, following the circadian rhythm of acute myocardial infarction (AMI) occurrence. Diabetes mellitus (DM) is associated with changes in circadian rhythm. We aimed to compare the temporal variation of OHCA occurrence over the day and week between OHCA patients with DM and those without.Methods: In two population-based OHCA registries (Amsterdam Resuscitation Studies [ARREST] 2010-2016, n = 4163, and Danish Cardiac Arrest Registry [DANCAR], 2010-2014, n = 12,734), adults (≥18y) with presumed cardiac cause of OHCA and available medical history were included. Single and double cosinor analysis was performed to model circadian variation of OHCA occurrence. Stratified analysis of circadian variation was performed in patients with AMI as immediate cause of OHCA.Results: DM patients (22.8% in ARREST, 24.2% in DANCAR) were older and more frequently had cardiovascular risk factors or previous cardiovascular disease. Both cohorts showed 24 h-rhythmicity, with significant amplitudes in single and double cosinor functions (P-range &lt; 0.001). In both registries, a morning peak (10:00-11:00) and an evening peak (20:00-21:00) was observed in both DM and non-DM patients. No septadian variation was observed in either DM or non-DM patients (P-range 0.13-84).Conclusions: In these two population-based OHCA registries, we observed a similar circadian rhythm of OHCA occurrence in DM and non-DM patients.</p

International Business in an Accelerated VUCA World: Trends, Disruptions, and Coping Strategies

It is clear that the current business environment has changed fundamentally over the past several years. Major transformations were well underway prior to the global pandemic, but the latter and the ensuing global recession made the business landscape even more extraordinary. This paper discusses the new realities which define the contemporary global economy and provides insights into the changing nature of cross-border business. Specifically, we examine some of the short and long-term trends and disruptions that impact business. We also explore potential coping mechanisms and strategies that can help business thrive in this new environment

Thigh-worn accelerometry for measuring movement and posture across the 24-hour cycle: a scoping review and expert statement

Introduction: The Prospective Physical Activity Sitting and Sleep consortium (ProPASS) is an international collaboration platform committed to harmonise thigh-worn accelerometry data. The aim of this paper is to (1) outline observational thigh-worn accelerometry studies and (2) summarise key strategic directions arising from the inaugural ProPASS meeting.Methods: (1) We performed a systematic scoping review for observational studies of thigh-worn triaxial accelerometers in free-living adults (n≥100, 24 hours monitoring protocols). (2)Attendees of the inaugural ProPASS meeting were sent a survey focused on areas related to developing ProPASS: important terminology (Q1); accelerometry constructs (Q2); advantages and distinct contribution of the consortium (Q3); data pooling and harmonisation (Q4); data access and sharing (Q5 and Q6).Results: (1) Eighty eligible articles were identified (22 primary studies; n~17 685). The accelerometers used most often were the ActivPAL3 and ActiGraph GT3X. The most commonly collected health outcomes were cardiometabolic and musculoskeletal. (2) None of the survey questions elicited the predefined 60% agreement. Survey responses recommended that ProPASS: use the term physical behaviour or movement behaviour rather than 'physical activity' for the data we are collecting (Q1); make only minor changes to ProPASS's accelerometry construct (Q2); prioritise developing standardised protocols/tools (Q4); facilitate flexible methods of data sharing and access (Q5 and Q6).Conclusions: Thigh-worn accelerometry is an emerging method of capturing movement and posture across the 24 hours cycle. In 2020, the literature is limited to 22 primary studies from high-income western countries. This work identified ProPASS's strategic directions-indicating areas where ProPASS can most benefit the field of research: use of clear terminology, refinement of the measured construct, standardised protocols/tools and flexible data sharing.</p

Feasibility of real-time three-dimensional stress echocardiography: pharmacological and semi-supine exercise

<p>Abstract</p> <p>Background</p> <p>Real time three dimensional (RT3D) echocardiography is an accurate and reproducible method for assessing left ventricular shape and function.</p> <p>Aim</p> <p>assess the feasibility and reproducibility of RT3D stress echocardiography (SE) (exercise and pharmacological) in the evaluation of left ventricular function compared to 2D.</p> <p>Methods and results</p> <p>One hundred eleven patients with known or suspected coronary artery disease underwent 2D and RT3DSE. The agreement in WMSI, EDV, ESV measurements was made off-line.</p> <p>The feasibility of RT-3DSE was 67%. The inter-observer variability for WMSI by RT3D echo was higher during exercise and with suboptimal quality images (good: k = 0.88; bad: k = 0.69); and with high heart rate both for pharmacological (HR < 100 bpm, k = 0.83; HR ≥ 100 bpm, k = 0.49) and exercise SE (HR < 120 bpm, k = 0.88; HR ≥ 120 bpm, k = 0.78). The RT3D reproducibility was high for ESV volumes (0.3 ± 14 ml; CI 95%: -27 to 27 ml; p = n.s.).</p> <p>Conclusions</p> <p>RT3DSE is more vulnerable than 2D due to tachycardia, signal quality, patient decubitus and suboptimal resting image quality, making exercise RT3DSE less attractive than pharmacological stress.</p