First-principles study of phase transition in theα-In2Se3/metal heterostructures

With the discovery of two-dimensional (2D) ferroelectric materials such as CuInP2S6andα-In2Se3, the ferroelectric field effect transistors (Fe-FETs) based on these materials have entered a rapid-development period. The metal/semiconductor contact is an unavoidable topic in the construction of devices. In this paper, heterostructuresα-In2Se3/metals (Pd, Pt, Cu, Ag and Au) are discussed. According to different stacking types, the structures and energy of 160 heterostructures are calculated and compared. Whenα-In2Se3contacts with the Pd, Pt and Cu, theα-In2Se3may transforms intoβ-In2Se3. This phenomenon has hardly been mentioned or analyzed in previous reports. Contacting with the Au and Ag, theα-In2Se3maintains the original structure. The internal physical mechanism of phase transition is explained from the binding energy and the charge transfer. The paper provides sufficient theoretical support for research and development of the Fe-FETs based onα-In2Se3.

Prevalence of human papillomavirus and the correlation of HPV infection with cervical disease in Weihai, China

OBJECTIVE

This study investigates the human papillomavirus (HPV) infection rate in female genital tracts, as well as the HPV genotype distribution and HPV correlation with cervical disease in Weihai, Shandong Province, China.

MATERIALS AND METHODS

A random sample of 9,460 volunteers was simultaneously screened using gene chips and examined by ThinPrep liquid-based cytology test (TCT). Cervical biopsy samples were collected from women with positive HPV-DNA and abnormal TCT for pathological diagnosis.

RESULTS

The overall HPV prevalence was 6.93% (656 of 9,460). A total of 753 subjects were infected with HPV subtypes (including multiple HPV infections). Of those with infections, 688 were infected with high-risk (HR) types (91.37%), and 65 were infected with low-risk subtypes (8.63%). The single-infection rate was 63.1%.The prevalence rates of HPV in women aged 20 to 39 years and 40 to 59 years were 7.29% and 6.71%, respectively. The most common genotype was HPV16. The HR genotypes were associated with cervical diseases such as atypical squamous cells of undetermined significance (ASCUS) (37.9%), atypical squamous cells high grade (ASC-H) (42.5%), low grade squamous intraepithelial lesion (LSIL) (50%), and high grade squamous intraepithelial lesion HSIL (66.7%). Cervical biopsy results show that the HPV detection rate increased in the following biopsy samples: cervical intraepithelial neoplasia (CIN) I (74.11%), CIN II (84.31%), CIN III (90.32%), and squamous-cell carcinoma (SCC) (100%).

CONCLUSIONS

The HPV infection rate with associated cervical disease in Weihai is equal to those in foreign countries but is lower than the average rate in China. The prevalence of HPV was higher in young people. The most common HPV genotype was 16, followed by 52 and 58. HR HPV is the most probable infection factor for cervical diseases.

[Differentiating gastric cancer cell from normal cell by laser Raman spectrum]

The gastric cancer cell and normal cell were comparatively detected by means of laser Raman spectrum in the present paper. The special Raman spectrum wave crest of gastric cancer cell was inquired. It was found that the special Raman spectrum wave crest of gastric cancer cell differs from the one of normal cell. After the sample at concentration of 1.25 x 10(5) individual x mL(-1) was cultivated for several days, a few special Raman spectrum wave crests of sample at 583, 633 and 656 nm respectively were detected. This is a few new special Raman spectrum wave crests rarely reported. Whether at the special Raman spectrum wave crests or at the same several Raman spectrum wave crests 674, 707, 773 and 799 nm for both canner cell and normal cell, the Raman spectrum intensity increases with the cancer cell concentration. As a result, the laser Raman spectrum analyse is considered truly a kind of rapid and effectual method to check cancer cell.

Protective effects of flunarizine on hemorrhagic shock in rats

Intravenous injections of flunarizine 0.25, 0.5, or 1.0 mg.kg-1 10 min before hemorrhage increased the maximal bleeding volume from 4.3 +/- 1.1 to 5.5 +/- 1.1 ml. As the dose of flunarizine increased, the survival time in rats subjected to hemorrhage was prolonged in a dose-dependent manner. Five hours after the reinfusion, flunarizine 1 mg.kg-1 markedly improved the survival rate to 70% compared with nil in the shock group. Flunarizine reduced the increase of lactate in blood, ameliorated the depletion of ATP stores in tissues, and prevented the calcium accumulation in heart and liver. The results suggest that flunarizine may produce a protective effect on hemorrhagic shock, probably related to the decrease of calcium accumulation in the ischemic tissues.

[Inhibitory effect of clonidine on hemolysis after thermal injury in animals]

Clonidine (1 mg.kg-1, ip) inhibited hemolysis in mice and rats after burn. The effects were abolished by pretreatment with yohimbine (5 mg.kg-1, ip) but not by prazosin (10 mg.kg-1, ip). The increased osmotic fragility of erythrocytes and the elevation of plasma NE level in burned animals were markedly lowered by clonidine which also raised the glutathione level of whole blood and enhanced the activity of glutathione peroxidase. These results indicated that the action of clonidine on hemolysis was carried out by means of depression of adrenergic alpha 2 receptors and reduction of free radicals.

[Inhibitory effects of clonidine on edema formation after thermal injury in mice and rats]

Clonidine 1 mg/kg ip given before thermal injury significantly inhibited the edema formation in mice and rats during the early stage of burn. Clonidine 0.1 mg/kg ip gave no such effect, but it became effective after being administrated via icv. The inhibitory effects of clonidine on edema formation were abolished by pretreatment with yohimbine 5 mg/kg ip, but not with prazosin 10 mg/kg ip. The tracing by 113mIn labelled transferrin demonstrated that clonidine decreased the capillary permeability in burned tissues 1 h after burn. When clonidine 1 mg/kg was given ip to the rats 20 min before burn, it lowered the level of lipoperoxide in the serum 2 h after burn. These results suggest that the inhibitory effects of clonidine on edema formation is most probably due to the depression of sympathetic activity via alpha 2 receptor during thermal injury.

[Antiarrhythmic effects of Cordyceps sinensis (Berk.) Sacc]

The administration of 65% alcohol extracts of Cordyceps sinensis can counteract the arrhythmias induced by aconitine or BaCl2 in rats, and increase the tolerant dose of ouabain to produce the arrhythmias in guinea pigs. The drug can reduce the heart rate of anesthetic rats, decreasing the contractility of isolated papillary muscle or atria in guinea pigs, but showing no effect on the automatic rhythmicity and the functional refractory period of the atria.