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81.
Introductory statistics texts give extensive coverage to two‐sided inferences in hypothesis testing, interval estimation, and one‐sided hypothesis tests. Very few discuss the possibility of one‐sided interval estimation at all. Even fewer do so in any detail. Two of the business statistics texts we reviewed mentioned the possibility of dividing the risk of a type I error unequally between the tails for a two‐sided confidence interval. None of the textbooks that were reviewed even considered the possibility of unequal tails for two‐sided hypothesis tests. In this paper, we propose that statistics courses and texts should cover both one‐sided tests and confidence intervals. Furthermore, we propose that coverage, at least in two semesters and advanced courses, should also be given to unequal division of the nominal risk of a type I error for both tests and confidence intervals. Examples are provided for both situations. 相似文献
82.
Dogan Ozgur Kivilcan 《International Journal of Science and Mathematics Education》2021,19(8):1563-1585
International Journal of Science and Mathematics Education - Given the importance of cultivating scientific literate societies, the integration of scientific inquiry into school curriculum is key... 相似文献
83.
This paper introduces an alternative method artificial neural networks (ANN) used to obtain numerical solutions of mathematical models of dynamic systems, represented by ordinary differential equations (ODEs) and partial differential equations (PDEs). The proposed trial solution of differential equations (DEs) consists of two parts: The initial and boundary conditions (BCs) should be satisfied by the first part. However, the second part is not affected from initial and BCs, but it only tries to satisfy DE. This part involves a feedforward ANN containing adjustable parameters (weight and bias). The proposed solution satisfying boundary and initial condition uses a feedforward ANN with one hidden layer varying the neuron number in the hidden layer according to complexity of the considered problem. The ANN having appropriate architecture has been trained with backpropagation algorithm using an adaptive learning rate to satisfy DE. Moreover, we have, first, developed the general formula for the numerical solutions of nth-order initial-value problems by using ANN.For numerical applications, the ODEs that are the mathematical models of linear and non-linear mass-damper-spring systems and the second- and fourth-order PDEs that are the mathematical models of the control of longitudinal vibrations of rods and lateral vibrations of beams have been considered. Finally, the responses of the controlled and non-controlled systems have been obtained. The obtained results have been graphically presented and some conclusion remarks are given. 相似文献
84.
Asma Farhat Sherwani Sameena Mohmood Fauzia Khan Rizwan Hasan Khan Md. Asim Azfer 《Indian journal of clinical biochemistry : IJCB》2003,18(2):169-180
Lectins, a group of specific glycoproteins present in animal as well as plant cells, are used as differentiating markers to
study cancers and metastatic cell lines. This property of lectins depends on the process of cellular glycosylation. Glycosylation
of some of the extracellular membrane proteins and lipids maintains the cell/cell and cell/matrix interactions. Chemical alterations
in glycosylation play an important role in the metastatic behavior of tumor cells. Carbohydrate residues of the membrane glycoproteins
can be detected using lectins due to their binding specificity to carbohydrates. Lectins, therefore have gained an importance
in the field of cancer research. Galectins, a specialized group of lectin like proteins that are Ca+ independent and galactoside
binding, are also considered as differentiation markers in some specific cancers like the carcinomas of thyroid.
Thus the use of lectins and galectins to identify specific carbohydrates present on cell surface help in invasion and metastasis
processes. 相似文献
85.
P. K. Nigam V. S. Narain Naveen Chandra V. K. Puri R. K. Saran S. K. Dwivedi M. Hasan 《Indian journal of clinical biochemistry : IJCB》1995,10(2):106-109
Blood samples from 39 patients with acute myocardial infarction and 15 healthy controls were analysed for serum and platelet sialic acid. Serum sialic acid levels in patients with acute myocardial infarction were significantly higher than controls (mean 2.7±0.46 μmol/ml Vs. 1.91±0.17 μmol/ml respectively). Levels of serum orosomucoid, an acute phase reactant, containing sialic acid, were also higher in these patients, suggesting a possible non-specific mechanism of increase in serum sialic acid concentration. In contrast, platelets contained significantly less sialic acid in patients with acute myocardial infarction than control (26.73±1.57 nmol/mg protein and 31.97±2.68 nmol/mg protein respectively). 相似文献
86.
Serum lipids and lipoproteins were estimated in 29 patients with acute myocardial infarction during acute phase (day 1,2,3),
predischarge and after three months. Serum total lipids, total cholesterol (TC) and LDL-cholesterol (LDLc) showed no significant
change during the hospital stay and three months followup. HDL-cholesterol (HDLc), however, started falling from day 2 onwards
with statistically significant reduction at pre-discharge and remained so at 3 months. The ratios of TC/HDLc and LDLc/HDLc
showed significant increase on predischarge day as compared to day 1. Serum triglycerides also showed an increasing trend
after myocardial infarction with a significant increase on day 3 and predischarge as compared to day 1. it is concluded that
the optimum time for assessment of serum lipid profile in patients with myocardial infarction seems to be within 24 hours
of the acute episode. 相似文献
87.
Yasir Hasan Siddique Tanveer Beg Mohammad Afzal 《Indian journal of clinical biochemistry : IJCB》2009,24(3):294-300
Hydrogen peroxide is one of the reactive oxygen species for cellular injury. It is overproduced during oxidative stress and
is known to damage proteins, nucleic acids and cell membranes. The present study was aimed to study the protective effect
of ascorbic acid against the toxic doses of hydrogen peroxide using lipid peroxidation and cytokinesis blocked micronucleus
assay. Hydrogen peroxide was studied at 50, 100 and 200μM and was found to increase a dose dependent increase in lipid peroxidation
and micronuclei frequency. The treatment of 100 and 200μM of hydrogen peroxide separately along with 20, 40 and 80μM of ascorbic
acid showed a dose dependent decrease in the lipid peroxidation and micronuclei frequency. The results suggest a protective
effect of ascorbic acid against the hydrogen peroxide induced oxidative damage in cultured human peripheral blood lymphocytes. 相似文献
88.
Knowledge Management Research & Practice - There are many times in our brave new web-based world that we seem to have lost the art of making common sense decisions and judgements. The current... 相似文献
89.
90.
Wen-Bei Yu Zhi-Yi Hu Jun Jin Min Yi Min Yan Yu Li Hong-En Wang Huan-Xin Gao Li-Qiang Mai Tawfique Hasan Bai-Xiang Xu Dong-Liang Peng Gustaaf Van Tendeloo Bao-Lian Su 《国家科学评论(英文版)》2020,7(6):1046
Active crystal facets can generate special properties for various applications. Herein, we report a (001) faceted nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture with unprecedented and highly stable lithium storage performance. Density functional theory calculations show that the (001) faceted TiO2 nanosheets enable enhanced reaction kinetics by reinforcing their contact with the electrolyte and shortening the path length of Li+ diffusion and insertion-extraction. The reduced graphene oxide (rGO) nanosheets in this TiO2/rGO hybrid largely improve charge transport, while the porous hierarchy at different length scales favors continuous electrolyte permeation and accommodates volume change. This hierarchically porous TiO2/rGO hybrid anode material demonstrates an excellent reversible capacity of 250 mAh g–1 at 1 C (1 C = 335 mA g–1) at a voltage window of 1.0–3.0 V. Even after 1000 cycles at 5 C and 500 cycles at 10 C, the anode retains exceptional and stable capacities of 176 and 160 mAh g–1, respectively. Moreover, the formed Li2Ti2O4 nanodots facilitate reversed Li+ insertion-extraction during the cycling process. The above results indicate the best performance of TiO2-based materials as anodes for lithium-ion batteries reported in the literature. 相似文献