At Least One Standard Deviation Above the Mean

SummaryThe characteristics of experimental error in measurement of platelet radioactivity have been explored by blind replicate determinations on specimens taken on several days on each of three Walker hounds.Analysis suggests that it is not unreasonable to suppose that error for each sample is normally distributed ; and while there is evidence that the variance is heterogeneous, no systematic relationship has been discovered between the mean and the standard deviation of the determinations on individual samples. Thus, since it would be impracticable for investigators to do replicate determinations as a routine, no improvement over simple unweighted least squares estimation on untransformed data suggests itself.

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PENGARUH PENDIDIKAN KESEHATAN REPRODUKSI PADA PEER GROUP (TEMAN SEBAYA) TERHADAP PENGETAHUAN DAN PERSEPSI REMAJA TENTANG PENDEWASAAN USIA PERKAWINAN DI SMA NEGERI 1 KECAMATAN NAMORAMBE KAB. DELI SERDANG 2018

COLOSTRUM : Jurnal Kebidanan ◽

10.36911/colostrum.v1i2.693 ◽

2020 ◽

Vol 1 (2) ◽

pp. 56-66

Author(s):

Irma Linda

Keyword(s):

Standard Deviation ◽

Health Education ◽

Reproductive Health ◽

Peer Group ◽

Peer Groups ◽

A Value ◽

Significant Difference ◽

Reproductive Health Education ◽

The Mean ◽

Adolescent Perceptions

Background: Early marriages are at high risk of marital failure, poor family quality, young pregnancies at risk of maternal death, and the risk of being mentally ill to foster marriage and be responsible parents. Objective: To determine the effect of reproductive health education on peer groups (peers) on the knowledge and perceptions of adolescents about marriage age maturity. Method: This research uses the Quasi experimental method with One group pre and post test design, conducted from May to September 2018. The statistical analysis used in this study is a paired T test with a confidence level of 95% (α = 0, 05). Results: There is an average difference in the mean value of adolescent knowledge between the first and second measurements is 0.50 with a standard deviation of 1.922. The mean difference in mean scores of adolescent perceptions between the first and second measurements was 4.42 with a standard deviation of 9.611. Conclusion: There is a significant difference between adolescent knowledge on the pretest and posttest measurements with a value of P = 0.002, and there is a significant difference between adolescent perceptions on the pretest and posttest measurements with a value of p = 0.001. Increasing the number of facilities and facilities related to reproductive health education by peer groups (peers) in adolescents is carried out on an ongoing basis at school, in collaboration with local health workers as prevention of risky pregnancy.

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Regularity and latency of units in ventral cochlear nucleus: implications for unit classification and generation of response properties

Journal of Neurophysiology ◽

10.1152/jn.1988.60.1.1 ◽

1988 ◽

Vol 60 (1) ◽

pp. 1-29 ◽

Cited By ~ 180

Author(s):

E. D. Young ◽

J. M. Robert ◽

W. P. Shofner

Keyword(s):

Standard Deviation ◽

Cochlear Nucleus ◽

Interspike Interval ◽

Rate Adaptation ◽

Stellate Cells ◽

Instantaneous Rate ◽

Ventral Cochlear Nucleus ◽

Bushy Cell ◽

Low Pass ◽

The Mean

1. The responses of neurons in the ventral cochlear nucleus (VCN) of decerebrate cats are described with regard to their regularity of discharge and latency. Regularity is measured by estimating the mean and standard deviation of interspike intervals as a function of time during responses to short tone bursts (25 ms). This method extends the usual interspike-interval analysis based on interval histograms by allowing the study of temporal changes in regularity during transient responses. The coefficient of variation (CV), equal to the ratio of standard deviation to mean interspike interval, is used as a measure of irregularity. Latency is measured as the mean and standard deviation of the latency of the first spike in response to short tone bursts, with 1.6-ms rise times. 2. The regularity and latency properties of the usual PST histogram response types are shown. Five major PST response type classes are used: chopper, primary-like, onset, onset-C, and unusual. The presence of a prepotential in a unit's action potentials is also noted; a prepotential implies that the unit is recorded from a bushy cell. 3. Units with chopper PST histograms give the most regular discharge. Three varieties of choppers are found. Chop-S units (regular choppers) have CVs less than 0.35 that are approximately constant during the response; chop-S units show no adaptation of instantaneous rate, as measured by the inverse of the mean interspike interval. Chop-T units have CVs greater than 0.35, show an increase in irregularity during the response and show substantial rate adaptation. Chop-U units have CVs greater than 0.35, show a decrease in irregularity during the response, and show a variety of rate adaptation behaviors, including negative adaptation (an increase in rate during a short-tone response). Irregular choppers (chop-T and chop-U units) rarely have CVs greater than 0.5. Choppers have the longest latencies of VCN units; all three groups have mean latencies at least 1 ms longer than the shortest auditory nerve (AN) fiber mean latencies. 4. Chopper units are recorded from stellate cells in VCN (35, 42). Our results for chopper units suggest a model for stellate cells in which a regularly firing action potential generator is driven by the summation of the AN inputs to the cell, where the summation is low-pass filtered by the membrane capacitance of the cell.(ABSTRACT TRUNCATED AT 400 WORDS)

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Blood Oxygenation Level Dependent Magnetic Resonance Imaging (MRI), Dynamic Contrast Enhanced MRI and Diffusion Weighted MRI for Benign and Malignant Breast Cancer Discrimination: A Preliminary Experience

Cancers ◽

10.3390/cancers13102421 ◽

2021 ◽

Vol 13 (10) ◽

pp. 2421

Author(s):

Roberta Fusco ◽

Vincenza Granata ◽

Mauro Mattace Raso ◽

Paolo Vallone ◽

Alessandro Pasquale De Rosa ◽

...

Keyword(s):

Standard Deviation ◽

Univariate Analysis ◽

Mean Value ◽

Blood Oxygenation ◽

Breast Lesions ◽

Dce Mri ◽

Malignant Lesions ◽

The Mean ◽

And Diffusion ◽

Skewness And Kurtosis

Purpose. To combine blood oxygenation level dependent magnetic resonance imaging (BOLD-MRI), dynamic contrast enhanced MRI (DCE-MRI), and diffusion weighted MRI (DW-MRI) in differentiation of benign and malignant breast lesions. Methods. Thirty-seven breast lesions (11 benign and 21 malignant lesions) pathologically proven were included in this retrospective preliminary study. Pharmaco-kinetic parameters including Ktrans, kep, ve, and vp were extracted by DCE-MRI; BOLD parameters were estimated by basal signal S0 and the relaxation rate R2*; and diffusion and perfusion parameters were derived by DW-MRI (pseudo-diffusion coefficient (Dp), perfusion fraction (fp), and tissue diffusivity (Dt)). The correlation coefficient, Wilcoxon-Mann-Whitney U-test, and receiver operating characteristic (ROC) analysis were calculated and area under the ROC curve (AUC) was obtained. Moreover, pattern recognition approaches (linear discrimination analysis and decision tree) with balancing technique and leave one out cross validation approach were considered. Results. R2* and D had a significant negative correlation (−0.57). The mean value, standard deviation, Skewness and Kurtosis values of R2* did not show a statistical significance between benign and malignant lesions (p > 0.05) confirmed by the ‘poor’ diagnostic value of ROC analysis. For DW-MRI derived parameters, the univariate analysis, standard deviation of D, Skewness and Kurtosis values of D* had a significant result to discriminate benign and malignant lesions and the best result at the univariate analysis in the discrimination of benign and malignant lesions was obtained by the Skewness of D* with an AUC of 82.9% (p-value = 0.02). Significant results for the mean value of Ktrans, mean value, standard deviation value and Skewness of kep, mean value, Skewness and Kurtosis of ve were obtained and the best AUC among DCE-MRI extracted parameters was reached by the mean value of kep and was equal to 80.0%. The best diagnostic performance in the discrimination of benign and malignant lesions was obtained at the multivariate analysis considering the DCE-MRI parameters alone with an AUC = 0.91 when the balancing technique was considered. Conclusions. Our results suggest that the combined use of DCE-MRI, DW-MRI and/or BOLD-MRI does not provide a dramatic improvement compared to the use of DCE-MRI features alone, in the classification of breast lesions. However, an interesting result was the negative correlation between R2* and D.

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Quantification of Measurement and Model Effects in Monopile Foundation Scour Protection Experiments

Journal of Marine Science and Engineering ◽

10.3390/jmse9060585 ◽

2021 ◽

Vol 9 (6) ◽

pp. 585

Author(s):

Minghao Wu ◽

Leen De Vos ◽

Carlos Emilio Arboleda Chavez ◽

Vasiliki Stratigaki ◽

Maximilian Streicher ◽

...

Keyword(s):

Standard Deviation ◽

Flow Field ◽

Three Dimensional ◽

Small Scale ◽

Maximum Wave Height ◽

Chaotic Flow ◽

The Mean ◽

Scour Protection ◽

Damage Number ◽

Measurement Effects

The present work introduces an analysis of the measurement and model effects that exist in monopile scour protection experiments with repeated small scale tests. The damage erosion is calculated using the three dimensional global damage number S3D and subarea damage number S3D,i. Results show that the standard deviation of the global damage number σ(S3D)=0.257 and is approximately 20% of the mean S3D, and the standard deviation of the subarea damage number σ(S3D,i)=0.42 which can be up to 33% of the mean S3D. The irreproducible maximum wave height, chaotic flow field and non-repeatable armour layer construction are regarded as the main reasons for the occurrence of strong model effects. The measurement effects are limited to σ(S3D)=0.039 and σ(S3D,i)=0.083, which are minor compared to the model effects.

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Rigorous time-domain analysis of statistically oriented graphene sheet fluctuations

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-02-2017-0105 ◽

2017 ◽

Vol 36 (5) ◽

pp. 1351-1363 ◽

Cited By ~ 1

Author(s):

Athanasios N. Papadimopoulos ◽

Stamatios A. Amanatiadis ◽

Nikolaos V. Kantartzis ◽

Theodoros T. Zygiridis ◽

Theodoros D. Tsiboukis

Keyword(s):

Monte Carlo ◽

Standard Deviation ◽

Finite Difference ◽

Surface Waves ◽

Time Domain ◽

Finite Difference Time Domain ◽

Mean Value ◽

Content Type ◽

The Mean ◽

Difference Time

Purpose Important statistical variations are likely to appear in the propagation of surface plasmon polariton waves atop the surface of graphene sheets, degrading the expected performance of real-life THz applications. This paper aims to introduce an efficient numerical algorithm that is able to accurately and rapidly predict the influence of material-based uncertainties for diverse graphene configurations. Design/methodology/approach Initially, the surface conductivity of graphene is described at the far infrared spectrum and the uncertainties of its main parameters, namely, the chemical potential and the relaxation time, on the propagation properties of the surface waves are investigated, unveiling a considerable impact. Furthermore, the demanding two-dimensional material is numerically modeled as a surface boundary through a frequency-dependent finite-difference time-domain scheme, while a robust stochastic realization is accordingly developed. Findings The mean value and standard deviation of the propagating surface waves are extracted through a single-pass simulation in contrast to the laborious Monte Carlo technique, proving the accomplished high efficiency. Moreover, numerical results, including graphene’s surface current density and electric field distribution, indicate the notable precision, stability and convergence of the new graphene-based stochastic time-domain method in terms of the mean value and the order of magnitude of the standard deviation. Originality/value The combined uncertainties of the main parameters in graphene layers are modeled through a high-performance stochastic numerical algorithm, based on the finite-difference time-domain method. The significant accuracy of the numerical results, compared to the cumbersome Monte Carlo analysis, renders the featured technique a flexible computational tool that is able to enhance the design of graphene THz devices due to the uncertainty prediction.

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Distance variable improvement of time-series big data stream evaluation

Journal Of Big Data ◽

10.1186/s40537-020-00359-w ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Ari Wibisono ◽

Petrus Mursanto ◽

Jihan Adibah ◽

Wendy D. W. T. Bayu ◽

May Iffah Rizki ◽

...

Keyword(s):

Time Series ◽

Standard Deviation ◽

Standard Method ◽

Time Series Data ◽

Series Data ◽

Percentage Error ◽

Traffic Demand ◽

Incremental Model ◽

Chernoff Bound ◽

The Mean

Abstract Real-time information mining of a big dataset consisting of time series data is a very challenging task. For this purpose, we propose using the mean distance and the standard deviation to enhance the accuracy of the existing fast incremental model tree with the drift detection (FIMT-DD) algorithm. The standard FIMT-DD algorithm uses the Hoeffding bound as its splitting criterion. We propose the further use of the mean distance and standard deviation, which are used to split a tree more accurately than the standard method. We verify our proposed method using the large Traffic Demand Dataset, which consists of 4,000,000 instances; Tennet’s big wind power plant dataset, which consists of 435,268 instances; and a road weather dataset, which consists of 30,000,000 instances. The results show that our proposed FIMT-DD algorithm improves the accuracy compared to the standard method and Chernoff bound approach. The measured errors demonstrate that our approach results in a lower Mean Absolute Percentage Error (MAPE) in every stage of learning by approximately 2.49% compared with the Chernoff Bound method and 19.65% compared with the standard method.

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Hemodynamic Status During Endovascular Stroke Treatment: Association of Blood Pressure with Functional Outcome

Neurocritical Care ◽

10.1007/s12028-021-01229-w ◽

2021 ◽

Author(s):

Min Chen ◽

Dorothea Kronsteiner ◽

Johannes Pfaff ◽

Simon Schieber ◽

Laura Jäger ◽

...

Keyword(s):

Blood Pressure ◽

Standard Deviation ◽

Functional Outcome ◽

Scale Score ◽

Endovascular Therapy ◽

National Institutes Of Health ◽

Modified Rankin Scale ◽

Vessel Occlusion ◽

Stroke Treatment ◽

The Mean

Abstract Background Optimal blood pressure (BP) management during endovascular stroke treatment in patients with large-vessel occlusion is not well established. We aimed to investigate associations of BP during different phases of endovascular therapy with reperfusion and functional outcome. Methods We performed a post hoc analysis of a single-center prospective study that evaluated a new simplified procedural sedation standard during endovascular therapy (Keep Evaluating Protocol Simplification in Managing Periinterventional Light Sedation for Endovascular Stroke Treatment). BP during endovascular therapy in patients was managed according to protocol. Data from four different phases (baseline, pre-recanalization, post recanalization, and post intervention) were obtained, and mean BP values, as well as changes in BP between different phases and reductions in systolic BP (SBP) and mean arterial pressure (MAP) from baseline to pre-recanalization, were used as exposure variables. The main outcome was a modified Rankin Scale score of 0–2 three months after admission. Secondary outcomes were successful reperfusion and change in the National Institutes of Health Stroke Scale score after 24 h. Multivariable linear and logistic regression models were used for statistical analysis. Results Functional outcomes were analyzed in 139 patients with successful reperfusion (defined as thrombolysis in cerebral infarction grade 2b–3). The mean (standard deviation) age was 76 (10.9) years, the mean (standard deviation) National Institutes of Health Stroke Scale score was 14.3 (7.5), and 70 (43.5%) patients had a left-sided vessel occlusion. Favorable functional outcome (modified Rankin Scale score 0–2) was less likely with every 10-mm Hg increase in baseline (odds ratio [OR] 0.76, P = 0.04) and pre-recanalization (OR 0.65, P = 0.011) SBP. This was also found for baseline (OR 0.76, P = 0.05) and pre-recanalization MAP (OR 0.66, P = 0.03). The maximum Youden index in a receiver operating characteristics analysis revealed an SBP of 163 mm Hg and MAP of 117 mm Hg as discriminatory thresholds during the pre-recanalization phase to predict functional outcome. Conclusions In our protocol-based setting, intraprocedural pre-recanalization BP reductions during endovascular therapy were not associated with functional outcome. However, higher intraprocedural pre-recanalization SBP and MAP were associated with worse functional outcome. Prospective randomized controlled studies are needed to determine whether BP is a feasible treatment target for the modification of outcomes.

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The use of clozapine in a rural and remote region of Australia

Australasian Psychiatry ◽

10.1177/1039856220975277 ◽

2020 ◽

pp. 103985622097527

Author(s):

Bridson Tahnee ◽

Abeysundera Hesitha ◽

Arunachalam Arulmathy ◽

Lam Anthea ◽

Mora Linda ◽

...

Keyword(s):

Standard Deviation ◽

Torres Strait Islander ◽

Psychotic Disorders ◽

Clinical Information ◽

Antipsychotic Treatment ◽

Rural And Remote ◽

Access To Treatment ◽

Regional Area ◽

The Mean ◽

Torres Strait

Objective: Clozapine is the most effective antipsychotic available for treatment-resistant schizophrenia. Unfortunately, it is often underutilised or administered late in the treatment course, if at all. This issue is further augmented in rural and remote regions where access to treatment is sparse. This study is the first of its kind to investigate the use of clozapine in a remote and regional area of Australia with a high proportion of Aboriginal and/or Torres Strait Islander individuals. Methods: This study includes all individuals who were commenced on clozapine between June 2013 and June 2018. Relevant clinical information was sourced from electronic medical records and descriptive statistical analysis performed. Results: A total of 3850 patients with psychotic disorders were reviewed over 5 years, of whom 63 were commenced on clozapine. The majority were male ( n = 50, 79.4%) with a mean age of 33.9 years (standard deviation 11.0). A total of 34.9% ( n = 22) identified as Aboriginal and/or Torres Strait Islander. The mean length of time between diagnosis and commencement of clozapine was 7.2 years (standard deviation ±4.6 years), while the mean number of antipsychotic medications tried prior to clozapine was 4.2 (standard deviation ±1.6 antipsychotics). Clozapine was discontinued in 57.1% of the individuals in this study (41% within the first 12 months). The most common cause for cessation was poor compliance ( n = 19, 30.2%). Conclusion: While clozapine remains the most effective antipsychotic treatment, it is often commenced late in the treatment or ceased prematurely. Further work is required, particularly in remote and regional populations, to ensure treatment adherence for optimal patient outcomes.

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