Standard Parameter Values Research Articles

Rift Valley fever: An open-source transmission dynamics simulation model.

Rift Valley fever (RVF) is one of the major viral zoonoses in Africa, affecting humans and several domestic animal species. The epidemics in eastern Africa occur in a 5-15 year cycle coinciding with abnormally high rainfall generally associated to the warm phase of the El Niño event. However, recently, evidence has been gathered of inter-epidemic transmission. An open-source, easily applicable, accessible and modifiable model was built to simulate the transmission dynamics of RVF. The model was calibrated using data collected in the Kilombero Valley in Tanzania with people and cattle as host species and Ædes mcintoshi, Æ. ægypti and two Culex species as vectors. Simulations were run over a period of 27 years using standard parameter values derived from two previous studies in this region. Our model predicts low-level transmission of RVF, which is in line with epidemiological studies in this area. Emphasis in our simulation was put on both the dynamics and composition of vector populations in three ecological zones, in order to elucidate the respective roles played by different vector species: the model output did indicate the necessity of Culex involvement and also indicated that vertical transmission in Ædes mcintoshi may be underestimated. This model, being built with open-source software and with an easy-to-use interface, can be adapted by researchers and control program managers to their specific needs by plugging in new parameters relevant to their situation and locality.

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High Precision Digitization of Paper-Based ECG Records: A Step Toward Machine Learning.

Introduction: The electrocardiogram (ECG) plays an important role in the diagnosis of heart diseases. However, most patterns of diseases are based on old datasets and stepwise algorithms that provide limited accuracy. Improving diagnostic accuracy of the ECG can be done by applying machine learning algorithms. This requires taking existing scanned or printed ECGs of old cohorts and transforming the ECG signal to the raw digital (time (milliseconds), voltage (millivolts)) form. Objectives: We present a MATLAB-based tool and algorithm that converts a printed or scanned format of the ECG into a digitized ECG signal. Methods: 30 ECG scanned curves are utilized in our study. An image processing method is first implemented for detecting the ECG regions of interest and extracting the ECG signals. It is followed by serial steps that digitize and validate the results. Results: The validation demonstrates very high correlation values of several standard ECG parameters: PR interval 0.984 +/−0.021 (p-value < 0.001), QRS interval 1+/− SD (p-value < 0.001), QT interval 0.981 +/− 0.023 p-value < 0.001, and RR interval 1 +/− 0.001 p-value < 0.001. Conclusion: Digitized ECG signals from existing paper or scanned ECGs can be obtained with more than 95% of precision. This makes it possible to utilize historic ECG signals in machine learning algorithms to identify patterns of heart diseases and aid in the diagnostic and prognostic evaluation of patients with cardiovascular disease.

Quantitative structure–activity relationship analysis of thiophene derivatives to explore the structural requirements for c-Jun NH2-terminal kinase 1 inhibitory activity

Background: With an aim to design a validated two-dimensional quantitative structure–activity relationship (2D QSAR) model, a probe was executed on a series of reported c-Jun NH2-terminal kinase-1 (JNK1) inhibitors, exhibiting selectivity toward JNKs (and not other members of MAPK family). Objective: The present work focused on obtaining valuable insights from the structural architecture of the selected compounds and their effects on JNK1 inhibitory activity. The present work deciphers the importance of descriptive variables, namely Verloop L (Subst. 1), Bond Dipole Moment (Subst. 2), LogP (Subst. 1), Balaban Topological index (Subst. 1), and VAMP Total Dipole (whole molecule), in molecules possessing JNK1 inhibitory profile. Results: These explanatory variables, obtained after iteratively reducing the data, did not only provide us with the substantial evidence pertaining to the dependence of bioactivity on the structural features of molecules, but also suggested the measures to optimize the selected compounds so as to obtain potent JNK1 inhibitors with good selectivity profile. Based on these distinct descriptors, exhibiting no apparent intercorrelation and manifesting good correlation with biological activity, a 2D QSAR model was generated. Conclusion: Robustness of the developed model was evaluated by performing multiple linear regression, partial least square, and artificial neural network studies. The reliability and predictive ability of the developed model was ascertained through the values of standard statistical parameters, such as s = 0.38, F = 97.22, r = 0.95, r2 = 0.90, and r2cv = 0.88, for the training set compounds. The generated model was validated through the test set compounds, as well as by leave one out method.

The Self-propulsion of a Foil with a Sharp Edge in a Viscous Fluid Under the Action of a Periodically Oscillating Rotor

This paper addresses the problem of controlled motion of the Zhukovskii foil in a viscous fluid due to a periodically oscillating rotor. Equations of motion including the added mass effect, viscous friction and lift force due to circulation are derived. It is shown that only limit cycles corresponding to the direct motion or motion near a circle appear in the system at the standard parameter values. The chart of dynamical regimes, the chart of the largest Lyapunov exponent and a one-parameter bifurcation diagram are calculated. It is shown that strange attractors appear in the system due to a cascade of period-doubling bifurcations.

New analytical approach for modelling effects of temperature and irradiance on physical parameters of photovoltaic solar module

In this paper, a new exact method has been presented to extract physical parameters of single diode equivalent circuit modelling a photovoltaic solar module operating at standard test conditions. The method uses four equations, three are linking output current to output voltage in short-circuit, maximum power and open-circuit points, the fourth equation is the first derivative of output power with regard to output voltage in maximal power point. According to this method, we used ideality factor η as variation parameter and solved the system of four nonlinear equations to get values of photocurrent Iph, saturation current Is, series resistance Rs and shunt conductance Gp. We then varied ideality factor to minimize root mean square error and maximize the coefficient of determination. We assumed series resistance and shunt conductance constant, and derived analytical expressions describing effects of module temperature and incident solar irradiance on photocurrent, on ideality factor and also on saturation current using both temperature coefficients available as well as irradiance coefficients extracted from module datasheet. We considered standard test conditions numerical values of physical parameters as initial conditions and determined numerical models for Iph(T,G), η(T,G) and Is(T,G). We also derived new mathematical expressions of maximum power point voltage and module efficiency. We tested these numerical models as well as mathematical expressions derived on Kyocera KC200GT and Shell SQ80 photovoltaic solar modules under different conditions of module temperature and incident solar irradiance and found good agreement between experimental and forecasted characteristics.

Water quality modeling for determination of suitability of water for shrimp farming in tidal rivers

Abstract In this study, the water quality of the Bahmanshir River and its water channels where Choebdeh Shrimp Farms (the largest shrimp culture complex in Iran) are located were simulated using MIKE11 software. First, an integrated hydraulic and salinity model of the river and its water channels was developed. Then, Manning and dispersion coefficients of the river were calibrated and validated. The most important parameters in the water quality model were determined by sensitivity analysis and these parameters were calibrated using in situ measured water quality data. The errors of salinity, temperature, nitrate, ammonia and dissolved oxygen (DO) models in the verification step were 7.9, 1.2, 0.34, 0.79 and 12%, respectively. Then, two scenarios were applied to the river and the effects of these scenarios on the water quality of the river and its channels were evaluated. The results demonstrated that the site selection of the shrimp culture complex had been performed well because different scenarios could not affect the water quality in the channels. Finally, the water quality in the channels was compared with the standard values of shrimp survival parameters. All of the parameters in the channels were in the range of standard values except DO, which was slightly under the standard value.

Quantifying walking ability in Japanese patients with knee osteoarthritis: Standard values derived from a multicenter study

BackgroundWe aimed to determine useful parameters for quantifying walking ability in patients with knee osteoarthritis. MethodsThis study included 621 Japanese patients with knee osteoarthritis scheduled to undergo total knee arthroplasty at any of 14 participating hospitals. Sex, age, body mass index, osteoarthritis severity (Kellgren–Lawrence grade), laterality, prior contralateral surgery, and pain were analyzed for their influence on walking ability, which was evaluated in terms of the 5-m walk test and the Timed Up and Go test outcomes during preoperative hospitalization. Patients were stratified based on dichotomized values of the independent influencing factors of walking ability, and the standard values for parameters describing walking ability were obtained. ResultsMultiple regression analysis revealed that sex, age, and Kellgren–Lawrence grade were factors influencing walking ability (5-m walk test and Timed Up and Go test outcomes). Therefore, the patients were stratified by sex, age, and Kellgren–Lawrence grade. The standard values (median values) for walking time on the 5-m walk test among patients aged 60–74/75–89 years were: 3.90/4.64 vs. 4.27/5.12 s for men vs. women with Kellgren–Lawrence grade III; 4.26/5.60 vs. 4.80/6.05 s for men vs. women with Kellgren–Lawrence grade IV. Regarding walking speed on the 5-m test, the standard values were: 1.28/1.08 vs. 1.17/0.98 m/s for men vs. women with Kellgren–Lawrence grade III; 1.17/0.89 vs. 1.04/0.83 m/s for men vs. women with Kellgren–Lawrence grade IV. Finally, the standard values for time on the Timed Up and Go test were: 8.52/10.30 vs. 9.30/11.74 s for men vs. women with Kellgren–Lawrence grade III; 9.40/12.90 vs. 10.05/13.20 s for men vs. women with Kellgren–Lawrence grade IV. ConclusionsThe standard values reported in this study can be used to quantify walking ability decline in patients with knee osteoarthritis and to aid in the decision to consider total knee arthroplasty.

Interfacility variation in treatment planning parameters in tomotherapy: field width, pitch, and modulation factor.

Several studies have reported changes in dose distribution and delivery time based on the value of specific planning parameters [field width (FW), pitch, and modulation factor (MF)] in tomotherapy. However, the variation in the parameters between different facilities is unknown. The purpose of this study was to determine standard values of the above parameters for cases of head and neck cancer (HNC) and prostate cancer (PC) in Japan. In this survey, a web-based questionnaire was sent to 48 facilities performing radiation therapy with tomotherapy in March 2016. The deadline for data submission was April 2016. In the questionnaire, the values of the planning parameters usually used were requested and 23 responses were received, representing a response rate of 48% (23/48). The FW selected was 2.5 cm in most facilities, and facilities with a tomoEDGE license used dynamic FW rather than fixed FW. Facilities changed the pitch based on FW, dose per fraction, or target offset more frequently in HNC than in PC. In contrast, >50% of the facilities used the magic number proposed by Kissick et al. Median preset MFs (range, min to max) in HNC and PC were 2.4 (1.8–2.8) and 2.0 (1.8–3.0), respectively, and MF values showed large variations between the facilities. Our results are likely to be useful to several facilities designing treatment plans in tomotherapy.

DISCOVERY OF NOVEL AND SELECTIVE C-JUN NH2-TERMINAL KINASES 2 INHIBITORS BY TWO-DIMENSIONAL QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIP MODEL DEVELOPMENT, MOLECULAR DOCKING AND ABSORPTION, DISTRIBUTION, METABOLISM, ELIMINATION PREDICTION STUDIES: AN IN SILICO APPROACH

Objective: Incited by the dearth of selective c-Jun NH2-terminal kinases (JNK) inhibitors, efforts have been made to design novel JNK2 inhibitors with good selectivity profile by utilizing a set of in silico tools.Methods: The present study involved 2D QSAR model development through multiple linear regression and partial least square methods. Further, the information unveiled through the above model was meticulously utilized to design novel JNK2 inhibitors (compound a and compound b). The selectivity of the novel molecules was ascertained through the molecular docking experiments. Determination of Tanimoto similarity index and absorption, distribution, metabolism, and elimination (ADME) properties was performed to ascertain the novelty and drug-like properties of the designed molecules, respectively.Results: Four explanatory variables or descriptors, moment of inertia 2 length (subst.1), moment of inertia 3 length (subst.3), Kier Chi4 (path/ cluster) index (whole molecule), and vamp highest occupied molecular orbital (whole molecule), were found to possess profound influence on the biological activity with the values of standard parameters, s: 0.28, r: 0.96, r2: 0.92, r2CV: 0.82, and f=59.69. Tanimoto index values were found to be 0.095 and 0.075 for compound a and compound b, respectively.Conclusion: The values of the statistical parameters proved the developed model to be of excellent quality. The results obtained for ADME prediction studies proved both the compounds to be better than the most potent compound (compound 45) of the set of JNK2 inhibitors selected for model development. In addition, extremely low Tanimoto similarity index values for both the compounds provided sufficient evidence for the novelty of the designed molecules.Objective: Incited by the dearth of selective c-Jun NH2-terminal kinases (JNK) inhibitors, efforts have been made to design novel JNK2 inhibitors with good selectivity profile by utilizing a set of in silico tools.Methods: The present study involved 2D QSAR model development through multiple linear regression and partial least square methods. Further, the information unveiled through the above model was meticulously utilized to design novel JNK2 inhibitors (compound a and compound b). The selectivity of the novel molecules was ascertained through the molecular docking experiments. Determination of Tanimoto similarity index and absorption, distribution, metabolism, and elimination (ADME) properties was performed to ascertain the novelty and drug-like properties of the designed molecules, respectively.Results: Four explanatory variables or descriptors, moment of inertia 2 length (subst.1), moment of inertia 3 length (subst.3), Kier Chi4 (path/ cluster) index (whole molecule), and vamp highest occupied molecular orbital (whole molecule), were found to possess profound influence on the biological activity with the values of standard parameters, s: 0.28, r: 0.96, r2: 0.92, r2CV: 0.82, and f=59.69. Tanimoto index values were found to be 0.095 and 0.075 for compound a and compound b, respectively.Conclusion: The values of the statistical parameters proved the developed model to be of excellent quality. The results obtained for ADME prediction studies proved both the compounds to be better than the most potent compound (compound 45) of the set of JNK2 inhibitors selected for model development. In addition, extremely low Tanimoto similarity index values for both the compounds provided sufficient evidence for the novelty of the designed molecules.

Evaluation of reference values of standard semen parameters in fertile Egyptian men.

The reference values of human semen, published in the WHO's latest edition in 2010, were lower than those previously reported. The objective of this study was to evaluate reference values of standard semen parameters in fertile Egyptian men. This cross-sectional study included 240 fertile men. Men were considered fertile when their wives had recent spontaneous pregnancies with time to pregnancy (TTP) ≤12months. The mean age of fertile men was 33.8±0.5years (range 20-55years). The 5th percentiles (95% confidence interval) of macroscopic semen parameters were 1.5ml for volume and 7.2 for pH. The 5th percentiles of microscopic parameters were 15million/ml for sperm concentration, 30million per ejaculate for total sperm count, 50% for total motility, 40% for progressive motility, 62% for vitality, 4% for normal sperm forms and 0.1million/ml for seminal leucocyte counts. In conclusion, fertile Egyptian men had higher reference values of sperm total motility, progressive motility and vitality, and lower reference values for total sperm counts as compared to those determined by the latest edition of the WHO laboratory manual in 2010. Other semen parameters were identical to those defined by the WHO 2010 manual.

Assessment of Hematological Profile in Amrith Mahal Breed of Cattle

The current study was undertaken with the objective of determining the reference values for hematological parameters for Amrith Mahal breed of cattle in general and in the subpopulations such as male, female and different age group of animals. A total of Twenty four healthy Amrith Mahal cattle were selected and divided into four groups based on sex and age as Group I (Young male of one to three years), Group II (Adult male of three to six years), Group III (Young female one to three years ) and Group IV (Adult female cattle of three to six years). Blood samples were collected from these animals and hematological parameters were determined by using hematology autoanalyzer and some by manual method. Mean and standard error values of the hematological parameters viz., TEC , TLC , Hb , PCV, TLC, DLC, MCV, MCHC for all the four groups were tabulated. The data presented in this study can be used as a baseline to study the haematological alterations due to nutritional deficiencies, physiological status, metabolic disorders and pathological conditions .

Method of assessing the influence of the moisture content in the braking fluid on the braking system actuation efficiency

Abstract The paper deals with assessing the influence of the braking fluid composition on the time of braking system actuation. It is justified that this factor should be taken into account in expert investigations of road accidents. The idea behind the research deals with putting forward proposals for improving the method for reconstructing road accidents by taking into account the braking fluid composition which can change during operation, resulting in increasing the time of brake drive actuation and in increasing the stopping distance of a vehicle equipped with a hydraulic braking system. The method of road accident reconstruction by adjusting standard (reference) values of braking parameters with consideration for properties of the braking fluid, affecting the time of deceleration rising up to its maximum and braking time with respect to steady deceleration, is reviewed. Experiments established the influence of the boiling temperature of the braking fluid and the moisture content on the total time of braking system actuation. A coefficient taking into account the influence of these factors on the estimated braking time and stopping distance of a vehicle is proposed and scientifically justified. The value of the paper lies in method application by automobile technical experts for the purposes of improving objectivity of expert evaluation results. The suggested refinements to the method allow improving and expanding the evidence base in road accident reconstruction in terms of the technical possibility to prevent the road accident, related to evaluation of the actual technical condition (as of the moment of the road accident) of the braking system equipped with a hydraulic drive.

Prediction of bleeding and thrombosis by standard biochemical coagulation variables in haematological intensive care patients.

We assessed the value of standard biochemical coagulation parameters in predicting bleeding, thrombosis and mortality in adult Intensive Care Unit (ICU) patients with haematological malignancies. We screened all patients with acute leukaemia and myelodysplastic syndrome admitted to a university hospital ICU during 2008-2012. Data were obtained from the clinical chemistry laboratory database and patient files. We graded bleeding according to the World Health Organisation (WHO)-system within 24-h, within 5-days and during the whole ICU stay. We analysed the predictive values of laboratory parameters using multiple logistic regression and receiver operator characteristics (ROC) curves. As we previously have established that platelet count at admission was associated with bleeding, we focused on International Normalised Ratio (INR), activated pro-thrombin time (APTT), anti-thrombin, D-dimer and fibrinogen, and markers of infection (C-reactive protein, pro-calcitonin), kidney function (creatinine) and tissue damage (lactate dehydrogenase (LDH)). We included 116 patients; 66 (57%) had at least one bleeding episode and 11 (9%) patients had at least one thrombotic event. The differences in coagulation values when bleeding compared to baseline values were minor. INR was the only variable we found associated with subsequent bleeding within 24 h from admission to ICU (odds ratio 2.91, 95% CI: 1.01-8.43, P = 0.048). ROC analyses did not show predictive value of any of the other variables with regards to bleeding and none of the variables were associated with thrombosis in adjusted analyses. Increased levels of LDH at admission were associated with increased 7-day and 30-day mortality. Increased INR at admission was associated with a higher rate of bleeding in ICU patients with haematological malignancies. No other biochemical coagulation or other parameter had any association with bleeding, thrombosis or mortality except increased LDH, which at ICU admission was associated with increased 30-day mortality.

Characteristics of dust acoustic waves in dissipative dusty plasma in the presence of trapped electrons

The formation and propagation of nonlinear dust acoustic waves (DAWs) as solitary and solitary/shock waves in an unmagnetized, homogeneous, dissipative and collisionless dusty plasma comprising negatively charged micron sized dust grains in the presence of free and trapped electrons with singly charged non-thermal positive ions is discussed in detail. The evolution characteristics of the solitary and shock waves are studied by deriving a modified Korteweg–de Vries–Burgers (mKdV–Burgers) equation using the reductive perturbation method. The mKdV–Burgers equation is solved considering the presence (absence) of dissipation. In the absence of dissipation the system admits a solitary wave solution, whereas in the presence of dissipation the system admits shock waves (both monotonic and oscillatory) as well as a combination of solitary and shock wave solutions. Standard methods of solving the evolution equation of shock (solitary) waves are used. The results are discussed numerically using standard values of plasma parameters. The findings may be useful for better understanding of formation and propagation of waves in astrophysical plasma.

Searching for Magnetar-powered Merger-novae from Short GRBS

Abstract The merger of a double neutron star (NS–NS) binary may result in a rapidly rotating massive NS with an extremely strong magnetic field (i.e., a millisecond magnetar). In this case, the magnetic spin-down of the NS remnant provides an additional source of sustained energy injection, which would continuously power the merger ejecta. The thermal emission from the merger ejecta would give rise to a bright optical “magnetar-powered merger-nova.” In this work, we carry out a complete search for magnetar-powered merger-nova from a Swift short gamma-ray burst sample. We focus on short GRBs with extended emission or internal plateau, which may signify the presence of magnetars as the central engine. We eventually find three candidates of magnetar-powered merger-nova from the late observations of GRB 050724, GRB 070714B, and GRB 061006. With standard parameter values, the magnetar remnant scenario could well interpret the multi-band data of all three bursts, including the extended emission and their late chromatic features in the optical and X-ray data. The peak luminosities of these merger-novae reach several times , more than one order of magnitude brighter than the traditional “kilo-novae” with peak luminosity of . Intense, multi-color, late-time observations of short GRBs are encouraged to identify more merger-novae in the future.

Transesophageal Echocardiography in Swine: Establishment of a Baseline

The porcine model is a commonly used animal model in cardiovascular research. Along with new innovative operative techniques, choice of the optimal imaging technique is crucial. Transesophageal echocardiography (TEE) is a reliable imaging tool is highly important in a large number of experimental evaluations. But so far, TEE data for swine are limited, and few standard values have been established for the porcine model. The experience and baseline results for TEE in 45 swine are presented in this study. A full TEE examination was conducted in 45 German landrace or German large white swine, with an average body weight of 49 ± 3 kg, before experimental off-pump mitral valved stent implantation. Additionally hemodynamic measurements were evaluated. The valve implantation procedure was guided solely by real-time 3-D TEE. Baseline values of standard echocardiographic parameters are provided and, where appropriate, compared with human reference values. TEE proved to be an adequate imaging technique in this experimental porcine animal model. The baseline TEE and hemodynamic parameters established for the widely used porcine model can serve as a reference in future studies.

Coagulation Management in Jersey Calves: An ex vivo Study

Objective: Jersey calves are frequently used as an experimental animal model for in vivo testing of cardiac assist devices or orthopedic implants. In this ex vivo study, we analyzed the coagulation system of the Jersey calves and the potential of human-based coagulation management to circumvent perioperative bleeding complications during surgery. Experimental Procedure: Blood from 7 Jersey calves was subjected to standard laboratory tests and thromboelastometry analysis. An ex vivo model of dilutional coagulopathy was used to study the effects of fibrinogen or prothrombin complex concentrate supplementation. Fibrinolysis was induced with tissue plasminogen activator to identify potential therapeutic strategies involving tranexamic acid or aprotinin. Furthermore, anticoagulation strategies were evaluated by incubating the blood samples with dabigatran or rivaroxaban. Results: Baseline values for thromboelastometry and standard laboratory parameters, including prothrombin time, activated partial thromboplastin time, fibrinogen, antithrombin III, and D-dimers, were established. Fifty percent diluted blood showed a statistically significant impairment of hemostasis. The parameters significantly improved after the administration of fibrinogen or prothrombin complex concentrate. Tranexamic acid and aprotinin ameliorated tissue plasminogen activator-induced fibrinolysis. Both dabigatran and rivaroxaban significantly prolonged the coagulation parameters. Conclusions: In this ex vivo study, coagulation factors, factor concentrate, antifibrinolytic reagents, and anticoagulants regularly used in the clinic positively impacted coagulation parameters in Jersey calf blood.

Reproducibility and Normative Values of the Parameters of a New Hand-Held Digital Pupillometer

We evaluated the intra-examiner reproducibility and determined the standard values of pupil parameters using the PLR-3000 pupillometer (NeurOptics Inc). Generally good reproducibility was obtained, except for the T75 parameter. The standard values may be useful to distinguish various neurological abnormalities in clinical practice.

Determination of liquid limit of a low swelling clay using different cone angles

The fall cone test is one of the most popular methods used to determine the soil liquid limit. In this study, a series of laboratory tests were conducted on kaolin soil, which is considered representative of low-swelling clays, in order to determine the penetration depths for different cone parameters (angle and weight) under a liquid limit state. The required soil undrained shear strength of kaolin at liquid limit was determined using a hand-held vane shear device. Based on the analysis of the test results, the relationship between the angle of the fall cone and the ratio of undrained shear strength and fall cone penetration depth over cone weight was obtained and represented by a power function. The established relationship was then used to determine the penetration depth at liquid limit for different cone parameter values. A difference in liquid limit of less than 15% was recorded between tests using standard and alternative cone parameter values, respectively. Furthermore, a better and more reliable result was obtained when cone angles were below 90°, with a standard deviation of less than 2.5% from the standard method. Based on critical analysis of the test data, an equation with which to determine the penetration depth under a liquid limit state, as well as a one-point test method with which to determine the liquid limit for different cone parameter values are proposed for low-swelling clays.