Period T0 Research Articles

Heart rate variability analysis for the prediction of pre-arousal during propofol-remifentanil general anaesthesia: A feasibility study.

Accidental awareness during general anaesthesia is a major complication. Despite the routine use of continuous electroencephalographic monitoring, accidental awareness during general anaesthesia remains relatively frequent and constitutes a significant additional cost. The prediction of patients' arousal during general anaesthesia could help preventing accidental awareness and some researchers have suggested that heart rate variability (HRV) analysis contains valuable information about the patient arousal during general anaesthesia. We conducted pilot study to investigate HRV ability to detect patient arousal. RR series and the Bispectral IndexTM (BISTM) were recorded during general anaesthesia. The pre-arousal period T0 was defined as the time at which the BISTM exceeded 60 at the end of surgery. HRV parameters were computed over several time periods before and after T0 and classified as "BISTM<60" or "BISTM≥60". A multivariate logistic regression model and a classification and regression tree algorithm were used to evaluate the HRV variables' ability to detect "BISTM≥60". All the models gave high specificity but poor sensitivity. Excluding T0 from the classification increased the sensitivity for all the models and gave AUCROC>0.7. In conclusion, we found that HRV analysis provided encouraging results to predict arousal at the end of general anaesthesia.

The Multifaceted Burden of Respiratory Syncytial Virus (RSV) Infections in Young Children on the Family: A European Study.

Since the majority of hospitalisations due to RSV occur in young children, the illness profoundly influences the entire family. However, comprehensive evidence regarding its overall effects remains limited. The ResQ Family study aims to investigate the burden of RSV-induced pediatric hospitalisation on affected families. Spanning the 2022-2023 RSV season, an interdisciplinary, observational study was conducted in Germany, France, Italy and Sweden. Using an online questionnaire, parents and caregivers of children (< 24months of age) with an RSV-induced hospitalisation were recruited. Information was gathered on topics related to RSV and parental health-related quality of life (HRQoL) during the acute infection phase (t0) and 6weeks later (t1). Descriptive evaluations of the data set were performed during t0 and regarding a potential change over the observation period (t0 vs. t1). Subgroup analysis aimed to further identify differences across the countries. A total set of 138 affected parents/caregivers were included in the study, with 59 participants responding to the follow-up survey (t1). Particularly during the acute infection phase, parental HRQoL was shown to be negatively influenced by the child's RSV infection [total score (p < 0.001, d = 0.54), parent HRQoL summary score (p < 0.001, d = 0.67) and family functioning summary score (p = 0.007, d = 0.33)]. Significant disparities in disease awareness and support structures were observed across Europe, with France and Sweden showing notably higher levels. The ResQ Family study provides convincing evidence that RSV-associated hospitalisations in young children across Europe generate a multifaced burden for the entire family, partly even beyond the acute infection phase. Standardised approaches for disease prevention at societal, educational and policy levels are needed to guarantee every newborn the best possible start into life. ClinicalTrials.gov, identifier, NCT05550545.

An enzyme-responsive core-double shell structured nano pesticide delivery system for improving the UV stability of emamectin benzoate (EB)

Currently, the inefficient application of pesticides results in substantial cost wastage and severe environmental contamination. The rapid advancement of nanomaterials and controlled/sustained-release technologies offer a promising guidance for reducing pesticide usage and enhancing pesticide bioavailability. In this study, naturally derived Zein and β-cyclodextrin (β-CD) polysaccharide were employed for synergistic encapsulation of emamectin benzoate (EB) pesticide molecule. Specifically, amino-functionalized Zein (AM-Zein) was effectively self-assembled onto β-cyclodextrin (β-CD) through electrostatic and hydrogen bonding interactions, with simultaneous encapsulation of EB through hydrophobic interactions, thereby establishing a core-double shell structured nano pesticide delivery system (EB@β-CD/AM-Zein). Compared to the single AM-Zein and β-CD, the double shell structured β-CD/AM-Zein demonstrated a notably higher encapsulation efficiency for EB. Importantly, the half-life period (t0.5) under UV irradiation of EB for EB@β-CD/AM-Zein was almost three times longer than that of EB alone. Enzyme-responsive controlled-release tests for EB@β-CD/AM-Zein revealed that the majority of EB was encapsulated within the inner β-CD layer. Specifically, the degradation of β-CD by α-amylase enabled the intelligent responsive release feature of EB. Moreover, the insecticidal activity of EB@β-CD/AM-Zein remained stable. This research offers valuable insights for developing effective and environmentally safe nano pesticide systems.

Remotely prescribed and monitored home-based gait-and-balance therapeutic exergaming using augmented reality (AR) glasses: protocol for a clinical feasibility study in people with Parkinson’s disease

BackgroundClinical guidelines for people with Parkinson’s disease (pwPD) stress that, complementary to pharmacological treatment, exercise and physiotherapy should be given a central role in disease management. Adhering to regular exercise of the right type, and with high repetition, remains a challenge for pwPD. Exergaming has the potential to increase adherence through play and personalised interventions, both in clinic and at home. Reality DTx® is an augmented-reality (AR) home-based gait-and-balance exergaming intervention specifically designed for pwPD as an extension of supervised physiotherapy. The primary objective of this study is to evaluate the feasibility and potential efficacy of Reality DTx®.MethodsTwenty-four pwPD (Hoehn and Yahr stages 2–4) with self-reported gait and/or balance impairments will participate in this study. The study comprises a 6-week waitlist-controlled AR home-based therapeutic gait-and-balance exergaming intervention. Reality DTx® will initially be prescribed remotely for a minimum of 5 days a week for 30 min per day. We will remotely set and adjust the frequency, difficulty, type of games, and/or duration weekly, based on objective and subjective data from the AR glasses and participant, respectively. In addition to the home-based gait-and-balance exergaming intervention, the study comprises three laboratory visits: before the 6-week waitlist period (t0; baseline), before the 6-week intervention period (t1; pre-intervention), and after the 6-week intervention period (t2; post-intervention). The primary study parameters are feasibility (in terms of safety, adherence, and user experience) and potential efficacy for improving gait and balance (using standard clinical gait-and-balance tests and a targeted walking-related fall-risk assessment). Recruitment started in December 2022 and the final post-intervention assessment will be according to planning in July 2023.ConclusionsThis clinical feasibility trial is the first remotely prescribed and monitored home-based AR gait-and-balance exergaming intervention for pwPD. The results in terms of clinical feasibility (i.e. safety, adherence, and user experience) and potential efficacy (gait, balance, and fall-risk outcomes) form the basis for future randomised controlled studies on the effectiveness of home-based AR gait-and-balance exergaming interventions for pwPD.Trial registrationClinicalTrials.gov, NCT05605249. Registered on 4 November 2022.

Effects of the “ICU Support” team meeting concept on patient-centered and staff-centered outcomes: study protocol for a randomized controlled multicenter study

BackgroundProviding optimal care for critically ill patients is an extremely important but also highly demanding task, both emotionally and physically. The “ICU Support” team meeting concept aims to support intensive care unit (ICU) teams by promoting interprofessional communication, peer support, and patient safety by providing a structure for daily team meetings. This protocol describes a study to explore the effectiveness of “ICU Support” for patient- and staff-centered outcomes.MethodsICU Support will be implemented at nine university hospitals located in Germany, following a two-arm randomized parallel group design with an intervention and a control condition and three data collection periods. In the intervention arm, leading ICU personnel (physicians and nurses) will be trained in ICU Support and implement the ICU Support elements into the daily work routine of their units upon completion of data collection period T0 (baseline). In the control arm, ICU Support will not be implemented until the completion of the data collection period T1 (1 month after study start). Until then, the regular daily schedule of the ICU teams will be maintained. The final data collection period (T2) will take place 4 months after the start of the study. Primary outcomes include the number of intensive care complications per patient during their ICU stay during T1 and the sick-related absence of ICU staff during T1. Secondary outcomes include, among others, the average severity of intensive care complications per patient and employee self-reported data regarding their teamwork and patient safety behaviors.DiscussionThe need for healthy and well-trained ICU staff is omnipresent; thus, structured and evidence-based interventions aimed at supporting ICU teams and facilitating patient safety are required. This multicenter study aims to explore the effectiveness of ICU Support for patient- and staff-centered outcomes. The insights derived from this study have the potential to significantly improve ICU patient safety, staff communication, and connectedness and decrease sickness-related expenses and social costs associated with high work demands among ICU staff.Trial registrationGerman Clinical Trials Register DRKS00028642. Registered on 4 April 2022.

Electrical conductivity anomalies study

Anomalous currents in a well-conducting body arise due to local electromagnetic induction inside the anomalous body, as well as due to conductive redistribution (and concentration) of currents induced in the host medium on a large territory equal to the external source size. The local induction generates the so-called anomaly of geomagnetic variations of the magnetic or inductive type. Its characteristic property is that the secondary anomalous field cannot be greater than the primary normal field of geomagnetic variations. However, in some places on the earth’s surface, the normalized anomalous fields are greater than 1. Analytical solution of the EM induction problem for circular cylinder yields the physical explanation of two types of anomalous geomagnetic fields. The first term (proportional to the normal electric field E0) describes the conductive anomaly type, the second term (proportional to the normal magnetic field B0) describes the inductive anomaly type. The conductive type usually is much greater than the inductive one. The normalized anomalous field of the conductive type is not limited to 1 or any other value. It is proportional to two functions: V(T) — the non-decreasing function of the period T (0≤V≤1, V=1 corresponds to DC) which describes the degree of filling of the conductor by anomalous currents (result of the skin effect inside the anomaly) and the normal impe­dance of inclosing cross-section — the decreasing function of the period. Product of these functions has a maximum at some period T0. The position T0 is closely related to the total lengthwise conductance G[S×m] of the anomalous body, that is, the scale of the anomaly. On the period T0, the anomalous fields and the induction vector become real C=Cu and the imaginary induction vector Cv passes through zero changing sign. Thus, the spectral properties of the geomagnetic response functions were studied for two-dimensional anomalies with a generalization to three-dimensional conductors with varying cross-section. 18 crustal electrical conductivity anomalies were considered and their integral lengthwise conductance G was obtained. At all anomalies, the G values turn out to be in a relatively narrow range G=(1—8)·108 S∙m; this has geophysical significance.

Influence of Regional Warming on Primary Production of the Kara Sea during the Last Two Decades (2002–2021)

Inter-annual (2002–2021) variability of the Kara Sea PP and associated environmental factors was assessed by MODIS-Aqua data and model calculations. Warming in the Kara Sea region during the last two decades was characterized by the pronounced positive trend of surface water temperature (T0) and weak positive trend of free-ice area (S) averaged for the growing season (April – October). During the investigated period T0 increased by 3.55°C with a trend of 10% y–1 and S increased by 110×103 km2 with a trend of 1.4% y–1, on average. The values of water column PP (IPP) statistically significant (p 0.05) decreased in the all of the Kara Sea regions (R2 = 0.22 – 0.59). For the entire Kara Sea the IPP declined by 38 mgC m–2 d–1 with a moderate trend of 1.1% y–1 (R2 = 0.37). The growing season averaged value of photosynthetically available radiation (PAR) weak, but statistically significant (p 0.05), decreased in the all of the Kara Sea areas (R2 = 0.20 – 0.31). Also, in the all regions the significant (R2 = 0.24 – 0.38) weak or moderate negative trends of surface chlorophyll a (Chl) were specified. The total annual PP (PPtot) increased insignificantly in accordance with increase of S (0.7% y–1, R2 = 0.08). The most significant decline of IPP was specified for spring (R2 = 0.28). In autumn the statistically significant positive trend of S (R2 = 0.24) was observed. Due to such increase of S, the strongest growth of PPtot was noted in autumn. In the present work was shown that decrease of IPP, resulting from decline of PAR and Chl, was the reason of moderation of PPtot. Weak increase in PPtot was observed in autumn and in the north area of the sea. It should be concluded that during the period of intense warming, the decrease in the IPP of the Kara Sea should affect the productivity of the higher trophic levels of the food web.

Inflammatory Indices during and after a Randomized Controlled Trial on Exercise in Old Adults: Could Moderate-intensity Exercise be Safe Enough? (Active Elderly and Health – Clinicaltrials.Gov, NCT03858114)

Background: Aging is characterized by a progressive increase in chronic diseases. According to WHO’s guidance, there is a need to develop strategies to monitor, maintain and rehabilitate the health of older people. The present research aims to elucidate whether or not a moderate physical activity intervention in older adults can cause an increase in inflammatory biomarker indices such as C-reactive Protein (CRP) and erythrocyte sedimentation rate (ESR). It is a valuable tool for promoting health that can be considered tolerable in the over-65 population. Methods: 120 males and females over 65 years of age participated in a randomized controlled trial (RCT NCT03858114) in two groups of 60 individuals of similar size and underwent moderate physical activity or cultural and recreational activities. The exclusion criteria were being younger than 65 years old, being unable to participate in physical activity for medical reasons, and a Body Mass Index of greater than 35. Blood samples from participants were collected for the pre-treatment period (t0), at the end of the study of 12 weeks (t1), and 20 weeks after the end of the study (t2) for measurement of inflammatory indices CRP and ESR. Results: The commonly routine tests for inflammatory reactions (ERS and CPR) showed no change at the end of an RCT on mild-to-moderate exercise. Conclusion: The results on inflammatory indices confirm the safety of this type of intervention and encourage its long-term use and testing.

Evaluation of the remineralizing effect of biomimetic self-assembling peptides in post-orthodontic white spot lesions compared to fluoride-based delivery systems: randomized controlled trial

ObjectivesTo evaluate the clinical performance of self-assembling peptides versus fluoride-based delivery systems in post-orthodontic white spot lesions.Materials and methodsThe participants were randomly assigned into two groups (n = 58) according to the remineralizing agent used, where (A) group represented participants receiving a varnish containing 22.600 fluoride ppm and tricalcium phosphate, while the second group (B) represented participants receiving self-assembling peptide. The remineralizing process of the white spot lesion was assessed using the DIAGNOdent pen and ICDAS scoring system according to the time when the remineralizing agent was used (T), where T0 represented the score taken at baseline. T1 represented the score taken after 3 months of follow-ups and T2 score represented the score taken after 6 months of follow-up. Data were collected and statistically analyzed. The parametric data: two-way ANOVA was used to test the effect of interaction among different variables. The non-parametric data: Mann–Whitney test was used. The significance level was set at p ≤ 0.05.ResultsThere was a quantitative statistically significant difference via DIAGNOpen readings between Group A (fluoride material) and Group B (self-assembling peptides). The highest mean value of 10.51 was found in Group A, while the least mean value of 6.45 was found in Group B. Besides, there was a significant difference in each group concerning the time factors T0, T1, and T2 groups where (p < 0.001. As for the qualitative results concerning the ICDAS score, there was no significant difference between the two groups along with the follow-up periods T0, T1, and T2 where the p value is equal to 0.064, 0.087, and 0.277 respectively.ConclusionsThe visual assessment using ICDAS reveals that the biomimetic remineralization using self-assembling peptides and the fluoride-based varnish material showed a similar effect in masking post-orthodontic white spot lesions. However, the laser fluorescence using DIAGNOpen showed that the self-assembling peptides reveal higher performance in subsurface remineralization than the fluoride-based varnish material. Therefore, self-assembling peptides are considered a promising material for lesion regression in post-orthodontics white spot lesions.Clinical relevanceSelf-assembling peptide SAP-14 is a new approach to reverse and mask off post-orthodontics white spot lesions.

Investigation of site properties of the Çaldıran (Van, Eastern Turkey) settlement area using surface wave and microtremor methods

Çaldıran (Van, eastern side of Turkey) which is a seismically very active region has more than active faults around and the areas under active tectonic effect. The earthquakes and soil characteristics are the significant factors that increase the severity of the damages ratio. For this reason, the characteristics of the engineering structure should be defined accurately and reliably. The shear wave velocity (Vs) obtained from geophysical methods is one of the most important parameters that determine the behavior of the soil during an earthquake. In this study, active and passive source surface wave methods were applied at different measurement points in the study area in order to determine soil properties of the settlement area and its surroundings in Çaldıran district the city of Van. As part of this study, 80 boreholes, 95 multichannel analysis of surface wave (MASW) profiles, and 66 microtremor (HVSR) measurements were performed in the study area. The Vs velocity with depth dependent could be determined by using the dispersive behavior of Rayleigh waves in surface wave analysis methods. In order to analyze the engineering characteristic of the region and earthquake-soil-structure relations parameters such as the amplification factor, predominant period (t0), Vs velocity, average velocity up to 30 m Vs30, and seismic vulnerability index (Kg) maps have been prepared. In order to reveal the variety of the engineering properties of the area in horizontal and vertical directions, depth cross-sections in different directions were created. When the tectonic structure and regional geology were examined, it was determined that all profile results were compatible with the geological structure.

Longitudinal patterns of comorbidity between anxiety, depression and binge eating symptoms among patients with obesity: A path analysis

BackgroundDepression, anxiety, and binge eating are common psychiatric symptoms among people with obesity. Although many studies seek to understand the mechanisms of association between these psychiatric symptoms, there is no still consensus about the longitudinal association. Methods155 patients (124 women) were recruited from a university-based bariatric center and evaluated over three waves (T0-T1-T2). In the last period the sample comprised 126 (104 women) participants. Trained clinicians assessed psychiatric symptoms by telephone interview using measurement scales. Partial Least Squares (PLS) was applied to investigate the path effects between anxiety, depression and binge eating symptoms over time. ResultsThe results of path coefficients (β) showed that the effect of anxiety on depression was constantly significant in all periods T0 (β = 0.74), T1 (β = 0.71), and T2 (β = 0.67). Anxiety had an effect on binge eating in T0 (β = 0.39) and T2 (β = 0.26) but not in T1. Binge eating affected depressive symptoms only in T2 (β = 0.22). Two carry-over-effects were significant binge eating in T0-T1 (β = 0.41) and T1-T2 (β = 0.19). LimitationsTelephone interviews, social isolation due to the pandemic and the social desirability may have contributed to collection and information biases. ConclusionAnxiety has significant path effects on depression and binge eating. Binge eating was shown to be the most unstable symptom over time. The time factor seems to contribute to path effects between the psychiatric symptoms. The results draw attention to the fact that psychiatric symptoms must be evaluated and treated in association with each other, and investigated over time.

Trend decomposition aids forecasts of air particulate matter (PM2.5) assisted by machine and deep learning without recourse to exogenous data

A near-past, trend-attribute extraction technique is proposed for short-term hourly particulate matter (PM2.5) forecasting. Multiple attributes are extracted from the univariate PM2.5 time-series data for the prior 12 h to forecast PM2.5 for the next 12 h with the aid of machine/deep learning (ML/DL) algorithms. The method avoids the uncertainties of using a selection of exogeneous variables to forecast PM2.5 trends that tend to be highly volatile with erratically spaced peaks. Fifteen trend-decomposed attributes are extracted for each hourly data record of a 2016 to 2020 dataset for Nottingham Centre (a city in the United Kingdom). The 41979 data records are evaluated by sixteen ML/DL forecasting models. Each model is trained and validated with two datasets (2016–2018 and 2016–2019) that are then used to forecast 5 h-ahead periods (t0, t+1, t+3, t+6 and t+12) for 2019 and 2020, respectively. ML models outperform DL models in forecasting PM2.5 for 2019 and 2020, because the DL models are adversely impacted by suboptimal convergence and/or overfitting. The best performing models are multiple linear regression (MLR) and support vector regression (SVR) that outperform traditional timeseries autoregressive models which estimate a parametric autocorrelation parameter, substantially so for time periods beyond t+1. The transparent MLR model reveals that all the trend-attribute variables considered influence the forecasts of the trained models, but their relative contribution varies according to the time period being forecast. Enabling the models to allocate different weights to each variable for different time period forecasts adds a useful dimension of flexibility to this method compared to autoregressive models.

The stability of berm breakwaters, state of art and sensitivity analysis

Berm recession plays a significant role in the design and assessment of berm breakwaters. In this study, different recession formulas were first thoroughly reviewed. Most of these formulas were developed based on mass armour berm breakwater tests, and some of the existing models contain many variables, while others have only a few parameters. Therefore, to determine the most significant parameters in these formulae, a comprehensive sensitivity analysis was conducted. It was found that the sensitivity of the recession to a particular parameter can be a function of several influencing parameters, and under some circumstances, some formulae are very sensitive to input variables. A comparison was made between the predicted recession and the measured one of the Sirevåg breakwater to investigate the performance of different formulas, which shows that Sigurdarson and Van der Meer (2013) formula performs better than others in this case.Furthermore, the impact of each governing parameter on the predicted berm recession was investigated. Results showed that the stability number is the significant parameter influencing the recession. However, there is an inconsistency between the formulae regarding the influence of T0 on the recession. Finally, experimental data was used to evaluate the sensitivities (of recession) obtained from different formulas, noting that these experimental data were obtained from research carried on a mass armour berm breakwater. The study revealed that Moghim et al. (2011) formulae showed reasonable performance regarding the influence of wave period T0 on the sensitivity of the recession, while Tørum et al. (2003) formulae was underestimating the sensitivity to T0. Moreover, it was found that Lykke Andersen (2006) formula is better fitted to the experimental data regarding the influence of the berm heigh (hbr) on recession.

Reduction of nitrophenol isomers and degradation of azo dyes through zero-valent Ni nanoparticles anchored on cellulose acetate coated Ce/Zr composite

In the current study, ceria/zirconia (Ce/Zr) was coated in cellulose acetate (CA) polymer to make a nanocomposite sheet known as CA-Ce/Zr which was used for the stabilization of Ni nanoparticles (NPs) and is named as CA-Ce/Zr@Ni NPs. The CA-Ce/Zr@Ni NPs was used as a dip-catalyst for the reduction of ortho/meta/para-nitrophenol (ONP, MNP, PNP), congo red (CR), and methyl orange (MO) dyes degradation in aqueous medium using NaBH4 as a reducing agent. The rate constant kapp value deduced from pseudo-first order kinetics was found highest for CR degradation which is 2.95 × 10−1 min−1 compare to MO dye (2.95 × 10−1 min−1). Similarly, PNP displayed the highest rate constant value of 4.26 × 10−2 min−1 compared to ONP (3.57 × 10−2 min−1), and MNP (4.05 × 10−2 min−1). Furthermore, approximately 91% of CR degradation was achieved in only 8 min. An induction period (t0) of 10 min was observed for nitrophenol isomers. The nanocomposite and its anchored Ni NPs was characterized through FESEM, XRD, and FTIR techniques. The supported Ni NPs was found stable after the reaction completion, and no leaching of the NPs was observed. Therefore, CA-Ce/Zr@Ni NPs could possibly be used for large scale applications.

The effect of rolling motion on flow resistance and heat transfer in narrow rectangular channel under natural circulation

With the increase demand for energy for ocean development, small reactors with natural circulation as the normal operating conditions are increasingly becoming an important energy supply option. The complex marine environment, such as fluctuations in the flow rate of coolant in nuclear reactor due to wind and waves, affects the flow resistance and heat transfer characteristic of the coolant, threatening the safety of the reactor. The current study performs one-dimensional and three-dimensional code coupling method to analyze the effect on flow resistance and heat transfer in a narrow rectangular channel under rolling condition. In addition to the influence of flow pulsation which has been considered universally by past studies, it was found that transverse mixed convection caused by external force fields, and boundary layer acceleration caused by the ununiform distribution of cross-section pressure, also have an impact on flow resistance and heat transfer. Unlike the flow pulsation, which has no effect on the time-average flow resistance and heat transfer, the transverse mixed convection increases the time-average flow resistance while also enhances the time-averaged heat transfer. Boundary layer acceleration occurs at lower Reynold number (Re≈800), and results in a steep increase in flow resistance, while the effect on heat transfer is not so significant. The relative strength of the three effects is impacted by the rolling parameters maximum rolling angle θ0 and period t0. The flow pulsation effect increases with increasing θ0 and decreasing period, while the mixed convection effect increases with increasing θ0.

ON THE METHOD OF DETERMINING LEARNING DESCRIPTIONS TO FORECAST NATURAL DISASTERS WITH THE PATTERN RECOGNITION SYSTEM

To forecast natural disasters (floods, mud-slides) in the fixed region and in period T0 with SPRL – the System of Pattern Recognition with Learning (elaborated by us) it is necessary to have the data of the previous 12 months of period T0 and learning descriptions (LDs). To identify this latter, the fact of occurrence or non-occurrence of disasters in the same region and the period T0 should be known in other years and also, the above mentioned 12- month date for each year. Determining LDs based on them is the aim of the article. For this purpose, the method which will be included in the first model of the SPRL is elaborated. The SPRL comprises: 1) preliminary elaboration of the initial information, 2) learning and 3) recognition models. This system is implemented on a PC. It is verified on the basis of the real data to recognize objects of different classis. Primary, additional and formal additional parameters are determined in the method given in the article. On the basis of their values in correlation with the aforementioned 12 months two matrices are determined. The first of them corresponds to the fact of occurrence of disasters and the second one – of non-occurrence. By using these parameter values given in these matrices LDs will be determined. The best LDs will be given to the learning model of the SPRL for transformation and increasing of informativity. Based on the LDs obtained after the transformation, the learning model will make knowledge and data bases.

The Impact of Financial Performance, Financial Risk, Liquidity, and Corporate Governance on Corporate Value

The purpose of this study is to analyze the impact of financial performance, financial risk, liquidity, and corporate governance (CG) on the corporate value in the period t0 and t+1. The proxy for financial performance, financial risk, liquidity, and corporate governance is respectively return on equity (ROE), debt to assets ratio (DAR), current ratio (CR), and corporate governance perception index (CGPI). The proxy for corporate value is price to book value (PBV). The method for analysis data is multiple linear regression analysis. The results show that financial performance has positive impact on the corporate value in the period t0 and t+1 on one percent level of significance. However, financial risk and liquidity have positive impact on the corporate value in the period t0 and t+1 but the impact is not statistically significant. CG shows different impact on the corporate value in the period t0 and t+1 in which it indicates negative impact in the period t0 but positive impact in the periode t+1. The impacts are however statistically insignificant. Generally, the results indicate that financial performance is the main factor that increases corporate value.

Magma Oscillations in a Conduit‐Reservoir System, Application to Very Long Period (VLP) Seismicity at Basaltic Volcanoes: 1. Theory

AbstractVery long period (VLP, 2–100 s) seismic signals at basaltic volcanoes like Kilauea, Hawai‘i, and Mount Erebus, Antarctica are likely from resonant oscillations of magma within the shallow plumbing system. The system consists of conduits connected to cracks (dikes and sills) or reservoirs of other shapes. A quantitative understanding of wave propagation and resonance in a coupled conduit‐crack system is required to interpret observations. In this work, we idealize the system as an axisymmetric conduit coupled to a tabular crack, accounting for fluid inertia, compressibility, and viscosity, buoyancy, and crack wall elasticity. We perform time domain simulations and eigenmode analyses of the governing equations, linearized about a rest state. The fundamental mode or conduit‐reservoir mode reflects the balance of conduit magma inertia with buoyancy (and, for small cracks, crack wall elasticity). Magma oscillates in an effectively incompressible manner within the conduit, deflating and inflating the crack, which couples to the surrounding solid to produce observable surface displacements. For sufficiently low viscosity magmas, viscous effects are confined to boundary layers. Shorter period modes are primarily reverberating crack waves with negligible coupling to the conduit. Finally, we introduce an approximate reduced model for the conduit‐reservoir mode, which can also handle more general reservoir geometries (e.g., spherical chambers). The reduced model connects the observable VLP period and quality factor to two uniquely constrained parameters: the inviscid oscillation period T0 and the viscous diffusion time τvis across the conduit radius. Our models can be extended to study the seismic response of more complex magmatic systems.

Comparison of Enamel Demineralisation Scores between Passive Self-Ligation Brackets and Conventional Ligation Brackets in Patients Undergoing Orthodontic Treatment- A Laser Fluorescence Study

Introduction: Enamel demineralisation is often seen in patients undergoing fixed orthodontic treatment because appliances create retentive areas around the brackets leading to food debris accumulation. The method of ligation is also an additional factor in causing plaque accumulation leading to demineralisation around the brackets. Aim: The present study aims to compare enamel demineralisation around self-ligation brackets and conventional ligation brackets at the 3rd month and 12th month of orthodontic treatment using laser fluorescence. Materials and Methods: The present prospective study aims to compare enamel demineralisation around self-ligation brackets (Damon 3mx) and conventional ligation brackets (Gemini 3M) at the 3rd month and 12th month of orthodontic treatment using laser fluorescence. Nineteen subjects who were scheduled for fixed orthodontic treatment were selected for the study and were divided into two groups that is conventional ligation and passive self-ligation. Diagnodent (DD) was used to take enamel demineralisation scores at the time of bonding (T0), 3 months (T1) and 12 months (T2) into treatment. All statistical analysis was performed using IBM SPSS version 20. Chi-square test was performed to find the gender association, One-way ANOVA test was carried out to evaluate the difference of DD scores at time period T0, T1 and T2 in self-ligation group and conventional ligation group and Independent t-test was carried out to evaluate the difference of DD scores between self-ligation brackets and conventional ligation at T0, T1 and T2. Results: One-way ANOVA test reported that in conventional ligation groups there was a statistically significant difference in the mean DD scores between T0 and T1, T0 and T2 (p&lt;0.05). Similarly, in the self-ligation group, a statistically significant difference was observed in the mean DD score between T0 and T1, T0 and T2 (p&lt;0.05). Independent t-test to evaluate the difference of mean DD scores between self-ligation brackets and conventional ligation at T2 was found to be statistically non-significant (p&gt;0.05). No gender association was noted. Conclusion: The method of ligation did not influence enamel demineralisation around orthodontic brackets.

Effect of Bicarbonate on Growth of the Oleaginous Microalga Botryococcus braunii

The effect of bicarbonate, produced by the enzymatic hydration of CO2 from postcombustion fumes, was investigated on Botryococcus braunii growth. The NaHCO3, supplied to cultures in the role of inorganic carbon source is proposed as a more eco-sustainable alternative to gaseous CO2. The salt was provided to the cultures at the final concentration of 0.5–1.5–2.5 g L−1. The growth rate was considered for specific time intervals (T0–T5, T5–T10 and T0–T10) showing values significantly higher in the culture supplemented with 2.5 g L−1 bicarbonate. The doubling times were also considered in all experimental cultures showing a faster doubling for the period T0 ÷ T5. The increase in pH drives the increase in growth in the experimental conditions in which the salt was added. The results suggest that bicarbonate is able to promote the algal growth, therefore it can be considered a valid alternative to CO2 gas.