297 research outputs found
Study on Unsupervised Feature Selection Method Based on Extended Entropy
Feature selection techniques are designed to find the relevant feature subset of the original features that can facilitate clustering, classification and retrieval. It is an important research topic in pattern recognition and machine learning. Feature selection is mainly partitioned into two classes, i.e. supervised and unsupervised methods. Currently research mostly concentrates on supervised ones. Few efficient unsupervised feature selection methods have been developed because no label information is available. On the other hand, it is difficult to evaluate the selected features. An unsupervised feature selection method based on extended entropy is proposed here. The information loss based on extended entropy is used to measure the correlation between features. The method assures that the selected features have both big individual information and little redundancy information with the selected features. At last, the efficiency of the proposed method is illustrated with some practical datasets
Recommended from our members
Interest rate regulation, earnings transparency and capital structure: evidence from China
We use samples from Chinese listed companies to investigate the effects of interest rate deregulation and earnings transparency on company’s capital structure in China over the period of 2003-2015. In particular, we study the link between state-owned enterprises (SOEs), economic growth targets, and marketization in China's unique institutional context. The results show earnings transparency increases firm leverage and the additional tests suggest that such an effect takes place via a mechanism by reducing the cost of debt finance. However, information transparency could moderate the effects of interest rate deregulation on corporate capital structure. In addition, SOEs are less sensitive towards the changes of interest rates in China because lending to SOEs is policy-oriented and lacks of market evaluation of business risk. Government control is conducive to enhancing the transparency of the whole industry, however, market-oriented reform is conducive to enhancing the transparency of the company's own information. The results are robust to endogeneity tests and a variety of variable and model specifications. Lastly, we find that information transparency has little impact on equity financing because of IPO and SEO strictly controlled by the Chinese government. The paper makes contribution to the relationship between earnings disclosure quality and capital structure in the Chinese unique institutional context, such as taking the progressive interest rate reform, SOES, different economic growth target and different marketization level in each province of China. We suggest that investors will pay more attention to the company's own unique information transparency in the provinces with high degree of marketization. As a potential direction for future research, we will investigate how the earnings transparency has impact on capital structure, and how such impact would depend on the transparency of specific business, the cap of foreign shareholding and the convenience of investment
Kinetics of HEX-BCC Transition in a Triblock Copolymer in a Selective Solvent: Time Resolved Small Angle X-ray Scattering Measurements and Model Calculations
Time-resolved small angle x-ray scattering (SAXS) was used to examine the
kinetics of the transition from HEX cylinders to BCC spheres at various
temperatures in poly(styrene-b- ethylene-co-butylene-b-styrene) (SEBS) in
mineral oil, a selective solvent for the middle EB block. Temperature-ramp SAXS
and rheology measurements show the HEX to BCC order-order transition (OOT) at
~127 oC and order-disorder transition (ODT) at ~180 oC. We also observed the
metastability limit of HEX in BCC with a spinodal temperature, Ts ~ 150 oC. The
OOT exhibits 3 stages and occurs via a nucleation and growth mechanism when the
final temperature Tf < Ts. Spinodal decomposition in a continuous ordering
system was seen when Ts< Tf < TODT. We observed that HEX cylinders transform to
disordered spheres via a transient BCC state. We develop a geometrical model of
coupled anisotropic fluctuations and calculate the scattering which shows very
good agreement with the SAXS data. The splitting of the primary peak into two
peaks when the cylinder spacing and modulation wavelength are incommensurate
predicted by the model is confirmed by analysis of the SAXS data
Leucine zipper transcription factor-like 1 expression in gastric cancer and its relationship to relative adhesion molecule
Purpose: To evaluate the expression of leucine zipper transcription factor-like1 (LZTFL1) molecule in the gastric cancer tissues, and its relationship to cellular adhesion protein.Methods: Expressions of LZTFLl, E-cadherin, β-catenin, intercellular cell adhesion molecule-1(ICAM-1) as well as vascular cell adhesion molecule-1 (VCAM-1) in the 133 gastric cancer samples and 40 gastritis samples were evaluated by immunohistochemistry. Levels of mRNA in gastric cancer and latero-cancer tissue were determined by real-time polymerase chain reaction (RT-PCR).Results: Protein levels in gastric tissue decreased. The expression of LZTFL1in gastric cancer tissue correlated with tumor stage (tumor node metastasis staging), degree of tumor differentiation and invasion depth (p < 0.05). Protein expression correlated with E-cadherin positively, and correlated with β-catenin and ICAM-1 negatively, but had no correlation with VCAM-1. Compared with tissues remote to the cancer, mRNA level of LZTFL1 in gastric cancer decreased significantly. There was no significant difference in LZTFL1 mRNA levels in the various clinical pathological tissues. LZTFL1 mRNA expression did not correlation with various adhesion factors.Conclusion: LZTFL1 is expressed at a low level in gastric cancer tissue. Its protein expression is related to cellular adhesion protein, but not to mRNA level. As a suppressor of invasion of cancer cells, LZTFL1 may be a potential target for targeted therapy of gastric cancer.Keywords: Leucine zipper transcription factor-like1 expression, Gastric cancer, Relative adhesion molecule, Protein expressio
Identification and expression analysis of two Wnt4 genes in the spotted scat ( Scatophagus argus )
Background: WNT4 is a protein that plays a crucial role in ovarian
differentiation and development in mammals, with a relatively well
understood function in mammalian gonadal differentiation. The role of
Wnt4 in teleost fish; however, remains unclear. In the present study,
cDNAs of Wnt4a and Wnt4b were cloned and characterized in the spotted
scat. The expression patterns of two Wnt4 genes in the gonads at
different stages of development and in fish after treatment with
17\u3b1-methyltestosterone (MT) were investigated. Results: The tissue
distribution showed that Wnt4a was expressed in various tissues,
including the gonads, gills, spleen, brain, and fin. Interestingly,
Wnt4b not only was expressed in the gills, brain, and spleen, but also
was obviously expressed in the ovary. During gonad development, Wnt4a
was highly expressed in the testis at stage I and Wnt4b was mainly
expressed in the ovary at stages II\u2013III. After MT treatment, the
mRNA expression of Wnt4a increased significantly up to 40 d, and the
transcript level of Wnt4b decreased at 20 d. Conclusions: These results
suggest that Wnt4a may be involved in gonad development and plays a
role in the process of spermatogonial proliferation. Our results also
demonstrate that Wnt4b is not only expressed in the nervous system, but
also in the ovary and it may be involved in ovary development of the
spotted scat
Establishing reference intervals of coagulation indices based on the ACL Top 700 system for children in Southwestern Fujian, China
Abstract(#br)Background(#br)Till date, China has not issued industry standards for reference intervals (RIs) of pediatric blood coagulation indices. Here, we evaluated changes in the coagulation indices in the venous blood of healthy children aged 29 days to 12 years derived using the ACL Top 700 system and established appropriate RIs.(#br)Methods(#br)We analyzed venous blood from 1770 healthy children for five coagulation indices. RIs were established according to the Clinical and Laboratory Standards Institute C28-A3c guideline.(#br)Results(#br)The coagulation indices were grouped by age. For prothrombin time (PT) and international normalization ratio (INR), the RIs of infants and toddlers were identical; preschool children had the same RI as school-age children. Pediatric RIs for PT and INR were slightly lower than those for adults. The RIs of activated partial thromboplastin time (APTT), thrombin time (TT), and fibrinogen (FIB) in childhood were divided into two groups by age (1 month to 1 year and 1–12 years). The RI of APTT in infants was the widest; the overall level of FIB in infants was the lowest; children’s APTT and FIB RIs were lower than those of adults. The pattern of TT values and RI trends in childhood were similar to those of APTT.(#br)Conclusions(#br)There were minor changes in the RIs of coagulation indices for children. The RIs of PT, INR, APTT, TT, and FIB must be grouped by age. The RIs of coagulation indices for children were different from those for adults; therefore, establishing separate RIs for children is necessary
Establishing reference intervals of coagulation indices based on the ACL Top 700 system for children in Southwestern Fujian, China.
BACKGROUND(#br)Till date, China has not issued industry standards for reference intervals (RIs) of pediatric blood coagulation indices. Here, we evaluated changes in the coagulation indices in the venous blood of healthy children aged 29 days to 12 years derived using the ACL Top 700 system and established appropriate RIs.(#br)METHODS(#br)We analyzed venous blood from 1770 healthy children for five coagulation indices. RIs were established according to the Clinical and Laboratory Standards Institute C28-A3c guideline.(#br)RESULTS(#br)The coagulation indices were grouped by age. For prothrombin time (PT) and international normalization ratio (INR), the RIs of infants and toddlers were identical; preschool children had the same RI as school-age children. Pediatric RIs for PT and INR were slightly lower than those for adults. The RIs of activated partial thromboplastin time (APTT), thrombin time (TT), and fibrinogen (FIB) in childhood were divided into two groups by age (1 month to 1 year and 1-12 years). The RI of APTT in infants was the widest; the overall level of FIB in infants was the lowest; children’s APTT and FIB RIs were lower than those of adults. The pattern of TT values and RI trends in childhood were similar to those of APTT.(#br)CONCLUSIONS(#br)There were minor changes in the RIs of coagulation indices for children. The RIs of PT, INR, APTT, TT, and FIB must be grouped by age. The RIs of coagulation indices for children were different from those for adults; therefore, establishing separate RIs for children is necessary
Effects of Active Components of Fuzi and Gancao Compatibility on Bax, Bcl-2, and Caspase-3 in Chronic Heart Failure Rats
Hypaconitine (HA) and glycyrrhetinic acid (GA) are active components of Fuzi (Aconitum carmichaelii) and Gancao (Glycyrrhiza uralensis Fisch); they have been used in compatibility for chronic heart failure (CHF) from ancient times. The purpose of the present research was to explore whether apoptosis pathways were related with the protective effects of HA + GA against CHF rats or not. The rats were progressed with transverse-aortic constriction (TAC) operation for 4 weeks to build the CHF state, and then the Digoxin (1 mg/kg), HA (2.07 mg/kg), GA (25 mg/kg), and HA (2.07 mg/kg) + GA (25 mg/kg) were orally administrated to rats for 1 week. The levels of BNP and cTnI in the plasma were decreased in the HA + GA group, and the heart/body weight ratio (H/B) and left ventricular (LV) parameters of transthoracic echocardiography were also declined; moreover, the expressions of Bax, Bcl-2, and caspase-3 were all improved in the HA + GA group than other groups in the immunohistochemistry and western blot methods. In general, the data suggested that Fuzi and Gancao compatibility could protect the CHF rats from apoptosis, which provided a strong evidence for further searching for mechanisms of them
1-(4-AminoÂphenÂyl)-3-[2-(trifluoroÂmethÂyl)phenÂyl]prop-2-en-1-one
The title compound, C16H12F3NO, a derivative of biologically active chalcones, comprises two benzene rings and a central –CH=CH—C(=O)– unit. The dihedral angle between the two rings is 10.9 (1)° and the molÂecule adopts an E configuration about the central olefinic bond. The crystal structure is stabilized by interÂmolecular N—H⋯O and N—H⋯N hydrogen bonds
- …