Radical Cation Salts of Hetera-Buckybowls: Polar Crystals, Negative Thermal Expansion and Phase Transition.

Radical cation salts of π-conjugated polycycles are rich in physical properties. Herein, two kinds of hetera-buckybowls, ethoxy-substituted trithiasumanene (3SEt) and triselenasumanene (3SeEt), are synthesized as electron donors. Galvanostatic oxidation of them affords radical cation salts (3SEt)5 (TTFMPB)3 , (3SeEt)5 (TTFMPB)3 , (3SEt)4 PMA, and (3SeEt)4 PMA, where PMA is Keggin-type phosphomolybdate and TTFMPB is tetrakis[3,5-bis(trifluoromethyl)-phenyl]borate. In these salts, 3SEt/3SeEt are partially charged and show distinct conformation change with the site charge and counter anions. In TTFMPB salts, (TTFMPB)- forms hexagonal channels that accommodate the packing columns of 3SEt/3SeEt. In particular, (3SEt)5 (TTFMPB)3 adopts the R3c space group and is a polar crystal with the columns of 3SEt all in the up-bowl direction. The PMA salts of 3SEt/3SeEt are polar crystals (C2 space group) with 3SEt/3SeEt being planar and forming columnar stacks. (3SeEt)4 PMA shows a structural modulation below 200 K, namely, negative thermal expansion (NTE) of the unit cell volume and enlargement of the intermolecular distances between neighboring 3SeEt molecules. The four salts are semiconductors with an activation energy of 0.18-0.38 eV. The conductivity of (3SeEt)4 PMA shows a reversible transition upon cooling and heating, in accordance to the NTE structural modulation. This work paves the way toward conducting materials based on hetera-buckybowls.

Transforming Hetera-Buckybowls into Chiral Conjugated Polycycles Incorporating Epoxycyclooctadiene: a Two-Step Approach.

Chiral π-conjugated polycycles have garnered increasing attention due to versatile applications in optoelectronic materials and biological sciences. In this study, we report the synthesis of chiral π-conjugated polycycles incorporating a chiral epoxycyclooctadiene moiety. Our synthetic strategy capitalizes on the novel reactions of hetera-buckybowl triselenasumanene (TSS) and is achieved in two-step manner. Firstly, the TSS is regio-selectively transformed into its ortho-quinone form. Subsequently, the nucleophilic addition reactions of TSS ortho-quinone by phenylethynides are metal ion-dependent. When utilizing (phenylethynyl)magnesium bromide as the nucleophile, two phenylethynyls are furnished onto the edged benzene ring of TSS. When the nucleophile is (phenylethynyl)lithium, a cascade of nucleophilic addition, intermolecular electron-transfer, ring-opening, and tetradehydro-Diels-Alder (TDDA) reactions occur sequentially in one-pot, ultimately affording chiral π-conjugated polycycles featuring the epoxycyclooctadiene moiety as an integral part of their backbones. This work represents a step forward in the synthesis of chiral π-conjugated polycycles using TSS as synthon.

Second-order nonlinearity in triangular lattice perforated gold film due to surface plasmas resonance.

We have studied the excitation second-order nonlinearity through a triangular lattice perforated gold film instead of square lattice in many papers. Under the excitation of surface plasmas resonance effect, the second order nonlinearity exists in the noncentrosymmetric split-ring resonators arrays. Reflection of fundamental frequency wave through a triangular lattice perforated gold film is obtained. We also described the second harmonic conversion efficiencies in the second order nonlinear optical process with the spectra. Moreover, the electric field distributions of fundamental frequency above the gold film region are calculated. The light propagation through the holes results in the enhancement of the second order nonlinearity including second harmonic generation as well as the sum (difference) frequency generation.

Effects of Kadsura coccinea L. Fruit Extract on Growth Performance, Meat Quality, Immunity, Antioxidant, Intestinal Morphology and Flora of White-Feathered Broilers.

This study aimed to determine whether adding Kadsura coccinea fruit extract to the diet of broilers could replace antibiotics. For this study, 300 one-day-old AA white feathered broilers were divided into five groups (no sex separated), with six repetitions per group (n = 10), as follows: blank control group (basal feed, CK group), positive drug (basal feed + 300 mg/kg aureomycin, PD group), and Kadsura coccinea low-dose, medium-dose, and high-dose groups (basal feed + 100 mg/kg, 200 mg/kg, and 300 mg/kg of Kadsura coccinea fruit extract, LD group, MD group and HD group). The experiment period was divided into early (1−21 days) and late (22−42 days) stage. We found that supplementation with Kadsura coccinea fruit extract in the diet significantly improved the growth performance of broilers (p < 0.05), reduced the feed to meat ratio (p < 0.05), reduced the fat percentage (p < 0.05), while had no significant effect on meat quality (p > 0.05) and Kadsura coccinea fruit extract could promote the development of immune organs to different extents, enhance antioxidant capacity, the contents of SOD and GSH-Px in serum were significantly increased (p < 0.05), improve the ratio of villus height to crypt depth. Finally, Kadsura coccinea fruit extract increased the relative abundance of probiotics and beneficial bacteria (Bacteroidales, NK4A214, Subdoligranulum and Eubacterium hallii) (p < 0.05) and reduced the relative abundance of harmful bacteria (Erysipelatoclostridium) (p < 0.05) in the gut of broilers. Compared with positive drug group, most of the indexes in the medium-dose group were better or had similar effects. We believe that Kadsura coccinea fruit extract can be used as a potential natural antibiotic substitute in livestock and poultry breeding programs.

[Research on the photoelectric conversion efficiency of grating antireflective layer solar cells].

A numerical investigation of the effect of grating antireflective layer structure on the photoelectric conversion efficiency of solar cells was carried out by the finite-difference time-domain method. The influence of grating shape, height and the metal film thickness coated on grating surface on energy storage was analyzed in detail. It was found that the comparison between unoptimized and optimized surface grating structure on solar cells shows that the optimization of surface by grating significantly increases the energy storage capability and greatly improves the efficiency, especially of the photoelectric conversion efficiency and energy storage of the triangle grating. As the film thickness increases, energy storage effect increases, while as the film thickness is too thick, energy storage effect becomes lower and lower.

Keto-enol-based modification on piperlongumine to generate a potent Cu(II) ionophore that triggers redox imbalance and death of HepG2 cells.

Altered redox status including higher levels of copper in cancer cells than in normal cells inspired many researchers to develop copper ionophores targeting this status. We have recently found that flavon-3-ol (3-HF) works as a potent Cu(II) ionophore by virtue of its keto-enol moiety. To further emphasize the significance of this moiety for developing Cu(II) ionophores, we herein designed a ß-diketo analog of piperlongumine, PL-I, characterized by the presence of high proportion of the keto-enol form in dimethylsulfoxide and chloroform, and identified its keto-enol structure by NMR and theoretical calculations. Benefiting from deprotonation of its enolic hydroxyl group, this molecule is capable of facilitating the transport of Cu(II) through cellular membranes to disrupt redox homeostasis of human hepatoma HepG2 cells and trigger their death.

[Cardioprotective effects of propofol and midazolam in children with congenital heart diseases undergoing open heart surgery].

OBJECTIVE: To observe the cardioprotective effects of propofol and midazolam in children with congenital heart diseases undergoing open heart surgery. METHODS: Thirty-two children with cyanotic congenital heart diseases of ASA classes I - II were randomly divided into 2 equal groups: propofol combined with low dose fentanyl group (Group PF) and midazolam combined with low dose fentanyl group (Group MF). The changes of hemodynaics, ECG, SpO2, nasopharyngeal and rectal temperatures were monitored continuously. The time of tracheal extubation and ICU staying time were recorded. Venous blood samples were collected when the venous channel was opened (T(0)), 2 h after declamping of the aorta (T(4)), and 24 h after operation (T(5)) to detect the plasma cardiac troponin I (cTnI). Myocardium samples were collected 10 - 20 min after aorta cross-clamp (T(2)), and 10 - 20 min after declamping of the aorta (T(3)) to undergo immunohistochemistry to observe the expression of heme oxygenase-1 (HO-1). RESULTS: The tracheal time of Group GF was 14.17 h, significantly shorter than that of Group MF (23.65 h, P < 0.05), and the ICU staying time of Group GF was 30.17 h, significantly shorter than that of Group MF (49.47 h, P < 0.05). The plasma cTnI level at T(4) of Group GF was 97 ng/ml +/- 33 ng/ml, significantly higher than those at T(0) (0.17 ng/ml +/- 0.10 ng/ml, P < 0.01) and T(5) (23 ng/ml +/- 13 ng/ml, P < 0.01). The plasma cTnI level at T(4) of Group MF was138 ng/ml +/- 56 ng/ml, significantly higher than those at T(0) (0.62 ng/ml +/- 0.96 ng/ml, P < 0.01) and T(5) (24 ng/ml +/- 6 ng/ml, P < 0.01). And the plasma cTnI levels at T(5) of these 2 groups were both significantly higher than those at T(0) (both P < 0.01), however, there was no significant difference in the plasma cTnI level at any time point between these 2 groups. The grey values of HO-1 in cardiac muscle cells at T(2) of Groups GF and MF were 182.2 +/- 0.8 and 193.5 +/- 1.4, both significantly higher than those at T(3) (125.6 +/- 2.1 and 145.5 +/- 7.4 respectively, both P < 0.01), and the grey values of HO-1 in cardiac muscle cells at T(2) and T(3) of Group MF were both significantly higher than those of Group GF (both P < 0.05). CONCLUSION: Both propofol and midazolam have protective effects for the children with congenital heart diseases undergoing open heart surgery, and propofol is superior to midazolam in the cardioprotection.

Heme oxygenase-1 inhibits neuropathic pain in rats with diabetic mellitus.

A diabetes mellitus model was established through single intraperitoneal injection of streptozotocin into rats. Seven days later, model rats were intraperitoneally administered zinc protoporphyrin, a heme oxygenase-1 inducer, and cobalt protoporphyrin, a heme oxygenase-1 inhibitor, once every two days, for 5 successive weeks. After administration, the paw withdrawal mechanical threshold of diabetic mellitus rats significantly decreased, the myelin sheath of the sciatic nerve thickened or showed vacuole defects, the number of spinal dorsal horn neurons reduced, some neurons degenerated and were necrotic, and heme oxygenase-1 was visible in the cytoplasm of spinal dorsal horn neurons. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling demonstrated that the number of apoptotic neurons increased, which could be inhibited by cobalt protoporphyrin, however, zinc protoporphyrin led to an opposite effect. Our experimental findings indicate that heme oxygenase-1 attenuates neuropathic pain in diabetic mellitus rats through amelioration of peripheral neuropathy and inhibition of spinal dorsal horn neuron apoptosis.