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  • Author: Gao-Feng Wang x
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This paper empirically examines the adverse selection models by using the data from China’s personal automobile insurance market through the standard positive-correlation test. Results show that higher-risk insurance policyholders do tend to buy insurance with a lower coinsurance rate, which supports the existence of adverse selection in China's automobile insurance market. This is quite a contrast to the findings in mature insurance markets.

Abstract

The synthesis of two new copper(II) complexes with benzimidazole type ligands, Cu(tta)2(L 1)2 (1) and Cu(tta)2(L 1) (2) (where L 1 is 3-(4-(1H-benzo[d]imidazol-1-yl)-4-methoxy phenyl)-1-phenylprop-2-en-1-one; tta is 2-thenoyltrifluoroacetonate), are reported. Their structures have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. The copper(II) ion of 1 is in a distorted octahedral environment, while that of 2 is in a distorted square-pyramidal environment. In both cases, the donor atoms are provided by oxygen atoms of the tta ligands and nitrogen atoms of the L 1 ligands.

Abstract

C27H18CuF6N2O5S2, triclinic, P1̄ (no. 2), a = 9.3162(5) Å, b = 10.1290(6) Å, c = 16.4352(9) Å, α = 90.430(4)°, β = 100.711(5)°, γ = 110.753(5)°, V = 1420.45(14) Å3, Z = 2, R gt(F) = 0.0559, wR ref(F 2) = 0.1617, T = 293 K.

Abstract

Background: Usually children mistakenly swallow foreign bodies, and most objects are spontaneously discharged through the digestive tract without consequence. However, sometimes the objects can cause gastrointestinal perforation, with serious complications.

Objective: To report the case of a 26-year-old male patient, who mistakenly swallowed a bamboo chopstick 14 years ago. The chopstick eventually perforated the gastric fundus and left diaphragm, pierced the lower left lobe of the lung, and caused a lower left lung abscess.

Method: A thoracotomy was conducted to remove the foreign body and the lower left lobe of the lung, followed by a patch fundoplication.

Result: The object was removed and the patient’s lesions healed after surgery.

Conclusion: The ingestion of foreign bodies rarely causes serious problems, but we should be vigilant to the occurrence of complications, and close follow-up should be conducted. This follow-up should include confirmation that the foreign body has passed through the alimentary tract.

Abstract

After catalyst screening for oxidative desulfurization of fuel oil within several polyoxometalates, H3PW6Mo6O40 was confirmed for the first time to be an effective and recoverable catalyst for the oxidative removal of thiophene, being also effective for the desulfurization of real diesel and gasoline.

Abstract

The current study investigated the effects of gamma radiation on the death rate, morphological traits and meiotic abnormalities in ground-grown chrysanthemum ‘Donglinruixue’, and inter-simple sequence repeat (ISSR) markers were used to identify the DNA polymorphism among mutants. The results showed that the death rate significantly increased with increase in radiation dose. Semi-lethal (LD50) dose was approximately 35 Gy. Compared with unirradiated control, plant growth was significantly inhibited. After irradiation, a series of morphological variations and cytological aberrations occurred in radiated plants. The peak in variation frequency appeared at 35 Gy. In total, ISSR analysis produced 72 scorable bands, of which 64 (88.89%) were polymorphic. The current study demonstrated that gamma irradiation generates a sufficient number of induced mutations and that ISSR analysis offered a useful molecular marker analysis for the identification of mutants.

Abstract

A three-step procedure has been developed for superhydrophobic coating on wood based on epoxy/silica materials in combination with hydrophobization. First, the epoxy resin is adhered to wood by immersing the samples into an epoxy resin acetone solution, then amino-functionalized silica particles are anchored by the epoxide groups, and finally, the created surface is modified by octadecyltrichlorosilane (OTS). The superhydrophobic surface not only is water repellent, as shown by the contact angle (CA) tests, but also decreases essentially the wood’s water absorption as determined by a 120-day water immersion test. The good mechanical stability of the coating was confirmed by a sand collision method.

Abstract

Aims: Infants less than 35 weeks' gestation age are susceptible to periventricular-intraventricular hemorrhage (PIVH). This may be partially attributable to low concentrations of vitamin K-dependent coagulation factors. The purposes of this study were: (1) to determine the umbilical blood activity levels of vitamin K-dependent coagulation factors II, VII, IX and X; (2) to investigate the change in activities of these factors in premature infants' umbilical blood after prenatal administration of vitamin K1 to the mothers; and (3) to study the prophylactic effects on PIVH after maternal antenatal supplemental vitamin K1.

Methods: Pregnant women in preterm labor at less than 35 weeks of gestation were randomly selected to receive antenatal vitamin K1 10 mg per day injection intramuscularly or intravenously for 2–7 days (vitamin K1 group, n=40), or no such treatment (control group, n=50). At the same period, cord blood samples were collected from thirty full-term neonates to compare the factor levels with those of premature infants. Intracranial ultrasound was performed by the same sonographer to determine the presence and severity of PIVH.

Results: The activities of vitamin K-dependent coagulation factors in umbilical blood in the control group were: factor II 25.64±9.49%, factor VII 59.00±17.66%, factor IX 24.67±8.88%, and factor X 30.16±5.02%. In full-term infants, the respective values were: factor II 36.70±4.88%, factor VII 64.54±10.62%, factor IX 30.18±5.69%, and factor X 34.32±12.63%. In vitamin K1 group these factors were: factor II 36.35±6.88%, factor VII 69.59±16.55%, factor IX 25.71±10.88%, and factor X 39.26±8.02%. The data suggest the absence of vitamin K-dependent coagulation factors in preterm infants, and antenatal supplement of vitamin K1 may increase the cord blood activity of factor II, VII and factor X (P<0.001). In addition, the overall rates of PIVH in the vitamin K1 group and in controls were 32.4 and 52.0%, respectively (P=0.036), and the frequency of severe PIVH was 5.0 and 20.0%, respectively (P=0.038).

Conclusions: Administration of vitamin K1 to pregnant women at less than 35 weeks' gestation age may result in improved coagulation and may reduce the incidence as well as the severity degree of PIVH.