F2 Treatment Research Articles

Improvement in the Property of Field Effect Transistor Having the HfO2/Ge Structure Fabricated by Photoassisted Metal Organic Chemical Vapor Deposition with Fluorine Treatment

We have fabricated Ge-based p-channel metal–insulator–semiconductor field effect transistor (p-MISFET) devices using a hafnium oxide (HfO2) gate film prepared by photoassisted metal organic chemical vapor deposition (MOCVD). To reduce the interface state of a HfO2/Ge gate stack, we performed a new F2 treatment method on a Ge surface. Before the deposition of HfO2 insulation thin films on n-type Ge(100), Ge surfaces were treated in fluorine (F2) gas ambient under various conditions. Experimental results show that F is densely distributed at the interface of the HfO2/Ge gate stack with the F2 treatment of the HfO2 bottom layers. Poorly passivated dangling bonds and oxygen vacancies (Vo) near the interface between HfO2 and Ge were stabilized by chemically active F. Consequently, the interface state density (Dit) of the HfO2/Ge gate stack was reduced and the electrical characteristics of the HfO2/Ge p-MISFETs were improved. Therefore, the new F2 treatment method is very useful for fabricating a good HfO2/Ge p-MISFET device.

Biological Evaluation of Polyherbal Ayurvedic Cardiotonic Preparation “Mahamrutyunjaya rasa”

Mahamrutyunjaya rasa (MHR), an Ayurvedic formulation, used as cardiotonic, contains potentially toxic compounds like aconitine, which are detoxified during preparation using traditional methods. Comparative toxicological evaluation of laboratory prepared formulation (F1) and two marketed formulations (F2 and F3) were performed based on their effects on viability of H9c2 cells and after single oral dose administration in mice. Cardioprotective effect of formulations at 25 and 50 mg/kg doses were studied in isoproterenol- (ISO-) induced myocardial infarcted rats. F1 and F2 did not affect the cell viability, while F3 decreased the cell viability in concentration and time-dependent manner. Rats administered with ISO showed significant increase in the serum levels of glutamate oxaloacetate transaminase, alkaline phosphotase, creatinine kinase isoenzymes, lactate dehydrogenase, and uric acid, while F1 and F2 treatment showed significant reduction in the same. F3 showed further increase in the serum levels of enzymes and uric acid in ISO-challenged rats. High pressure liquid chromatographic analysis of formulations showed higher concentration of aconitine in F3. Study shows that F1 and F2 possess cardioprotective property with higher safety, while formulation F3 cannot be used as cardioprotective due to its cytotoxic effects. Thus, proper quality assessment methods are required during preparation of traditional formulations.

Effect of municipal wastewater with manure and fertilizer on yield and quality characteristics of forage in corn

In order to study the effects of wastewater with two kinds of fertilizers (manure and chemical fertilizer) on yield and quality characteristics of forage in corn, a field experiment was conducted in the University of Zabol in Iran during 2007 growing season. The experiment was conducted in split plot design with three replications. The treatment were comprised of two levels of irrigation water (W1 = Well water and W2 = Wastewater) in the main plot and five levels of fertilizer (F1 = Control; F2 = Manure, 30 ton/ha; F3 = Manure, 15 ton/ha; F4 = NPK: 350, 200 and 100 kg/ha; and F5 = NPK: 175, 100 and 50 kg/ha) in the sub plot. Results showed that irrigation with wastewater significantly increases the fresh and dry forage yield of corn than well water. Treatment of treated wastewater also had a significant influence on crude protein content, ash percentage and macro elements (N, P and K) contents in corn forage (P < 5%). But wastewater had no significant effect on Fe, Mn and Zn elements content. The highest fresh and dry forage yield and the most crude protein content, ash percentage and macro elements (N, P and K) contents were obtained from F4 (NPK: 350, 200 and 100 kg/ha) treatment. However, the highest Fe, Mn and Zn elements content were obtained from F2 (Manure: 30 ton/ha) treatment.

Effects of &amp;lt;italic&amp;gt;N&amp;lt;/italic&amp;gt;-n-butyl Haloperidol Iodide on Myocardial Ischemia/Reperfusion Injury and &amp;lt;italic&amp;gt;Egr-1&amp;lt;/italic&amp;gt; Expression in Rat

We have previously shown that N-n-butyl haloperidol iodide (F2) derived from haloperidol reduces ischemia/reperfusion-induced myocardial injury by blocking intracellular Ca2+ overload. This study tested the hypothesis that cardio-protection with F2 is associated with an attenuation in the expression of early growth response gene 1 (Egr-1). In an in vivo rat model of 60 min coronary occlusion followed by 180 min of reperfusion, treatment with F2 significantly reduced myocardial injury evidenced by the reduction in release of plasma creatine kinase, myocardial creatine kinase isoenzyme and lactate dehydrogenase. In cultured neonatal rat cardiomyocytes of hypoxia for 3 h and reoxygenation for 1 h, F2 treatment attenuated necrotic and apoptotic cell death, as demonstrated by electron microscopy. Concomitant with cardio-protection by F2, the increased expression levels of Egr-1 mRNA and protein were significantly reduced in myocardial tissue and cultured cardiomyocytes as detected by reverse transcription-polymerase chain reaction, immunohistochemistry and immunocytochemistry. In conclusion, these results suggest that the protective effect of F2 on ischemia/reperfusion- or hypoxia/reoxygenation-induced myocardial injury might be partly mediated by downregulating Egr-1 expression.

Autologous Human-Derived Bone Marrow Cells Exposed to a Novel TGF-β 1 Fusion Protein for the Treatment of Critically Sized Tibial Defect

We report the first clinical case of transplantation of autologous bone marrow-derived cells in vitro exposed to a novel recombinant human transforming growth factor (rhTGF)-beta1 fusion protein bearing a collagen-binding domain (rhTGF-beta(1)-F2), dexamethasone (DEX) and beta-glycerophosphate (beta-GP). When such culture-expanded cells were loaded into porous ceramic scaffolds and transplanted into the bone defect of a 69-year-old man, they differentiated into bone tissue. Marrow cells were obtained from the iliac crest and cultured in collagen gels impregnated with rhTGF-beta1-F2. Cells were selected under serum-restricted conditions in rhTGF-beta(1)-F2-containing medium for 10 days, expanded in 20% serum for 22 days and osteoinduced for 3 additional days in DEX/beta-GP-supplemented medium. We found that the cell number harvested from rhTGF-beta(1)-F2-treated cultures was significantly higher (2.3- to 3-fold) than that from untreated cultures. rhTGF-beta(1)-F2 treatment also significantly increased alkaline phosphatase activity (2.2- to 5-fold) and osteocalcin synthesis, while calcium was only detected in rhTGF-beta(1)-F2-treated cells. Eight weeks after transplantation, most of the scaffold pores were filled with bone and marrow tissue. When we tested the same human cells treated in vitro in a rat model using diffusion chambers, there was subsequent development of cartilage and bone following the subcutaneous transplantation of rhTGF-beta(1)-F2-treated cells. This supports the suggestion that such cells were marrow-derived cells, with chondrogenic and osteogenic potential, whereas the untreated cells were not under the same conditions. The ability for differentiation into cartilage and bone tissues, combined with an extensive proliferation capacity, makes such a marrow-derived stem cell population valuable to induce bone regeneration at skeletal defect sites.

In vivo antioxidant activity of polysaccharide fraction from Porphyra haitanesis (Rhodephyta) in aging mice

Sulfated polysaccharide fraction F2 from Porphyra haitanesis (Rhodephyta) showed inhibitory effect on the in vitro lipid peroxidation. In the present study, the age-related changes in the antioxidant enzyme activity, lipid peroxidation, and total antioxidant capacity (TAOC) in different organs in mice were investigated and the in vivo antioxidant effect of F2 in aging mice was checked. Increased endogenous lipid peroxidation and decreased TAOC were observed in aging mice. Intraperitoneal administration of F2 significantly decreased the lipid peroxidation in a dose-dependent manner. F2 treatment increased TAOC and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in all the organs tested in aging mice. It is concluded that the sulfated polysaccharide fraction F2 can be used in compensating the decline in TAOC and the activities of antioxidant enzymes and thereby reduces the risks of lipid peroxidation.

Characterization of F 2 Treatment Effects on Si(100) Surface and Si(100)/SiO 2 Interface

Effects of F2 treatment on the Si(100) surface have been characterized using infrared reflection absorption spectroscopy (IR-RAS). Hydrogen desorbs first from Si–H, and desorption from Si–H2 and Si–H3 follows subsequently, when the n-Si(100) wafer terminated by Si–H, Si–H2 and Si–H3 is exposed to F2 gas. Moreover, the hydrogen of Si–H2 desorbs faster on a terrace than on an edge. Finally, the Si(100) surface is covered by Si–F and Si–F2.

The Effect of Dimethoate on Bone Marrow Cell Chromosomes of Rats in Subchronic Four-Generation Experiments

The effect of the insecticide dimethoate (O,O-dimethylS-/N-methylcarbamoylmethyl phosphorodithioate) on bone marrow cells of four generations of rats was investigated. Male and female Wistar rats were treated for 6 weeks with 5 treatments per week via gavage at doses of 7.0, 9.33, and 14.0 mg/kg (1/100, 1/75, and 1/50 of the LD50). Chromosomes of 10 of the treated males were prepared. Other males (6–8 males per dose) were paired with females (11–16 females per dose). This represented the first (P) generation. During pregnancy and lactation females were treated with adequate doses of dimethoate. In F1 (70 males and 56 females), F2 (71 males and 62 females), and F3 generations (62 males and 44 females) treatment with dimethoate and the preparation of chromosomes (40 males per generation) were the same as those in the P generation. Following treatment with dimethoate in P and F1 generations, the number of numerical chromosome aberrations increased significantly. No significant changes in chromosome aberrations were found in F2 and F3 generations compared to the control groups. The frequency of numerical chromosome aberrations decreased considerably compared to the P generation at the dose of 14.0 mg/kg (1/50 of LD50).

Oxygen and Fluorine Treatment Effect on Silicon Surface Characterized by Infrared Reflection Absorption Spectroscopy

Chemical bonds on Si(111) such as Si-H, Si-O and Si-F have been precisely measured by infrared reflection absorption spectroscopy. A Si wafer 4 inches in diameter was treated in various atmospheres in the temperature range from room temperature to 400° C. The heat treatment at 400° C in vacuum removes H bonded with Si from edge sites of the terrace plane, and oxygen treatment at 400° C removes H bonded with Si from the terrace plane. Initial oxidation begins at about 200° C in vacuum before H desorption. F2 treatment at room temperature removes H from Si and forms Si-F bonds immediately. Reflection peaks due to absorption arising from Si-F bonds shift from 850 cm-1 to higher wave number with further treatment and three peaks appear corresponding to SiFx (x=2-4) . Fluorination near the Si surface might be induced as the absorption of SiFx increases with the treatment time.

Fluorine Termination of Silicon Surface by F2 and Succeeding Reaction with Water

The F2 treatment of a hydrogen-terminated Si(100) surface in a vacuum chamber was chosen to generate a densely fluorinated silicon surface. It was confirmed by IR-attenuated total reflection and X-ray photoelectron spectroscopy measurements that the Si-H bonds on the surface were replaced with the Si-F bonds and that 1.0 monolayer of the Si-F bonds was formed after 1×104 L exposure. Mass spectrometry measurements of the volatile reaction products indicated that the Si-F bonds were produced by the following reaction: {SiH(surface)+F2(gas)→Si-F(surface)+HF(gas)}. The variation of thus prepared surface in water was also studied. The 1.0 monolayer of Si-F bonds was found to be replaced with the 0.7 monolayer of Si-H bonds and the 0.2-0.3 monolayer of Si-OH bonds after dipping into water for 1 min. The replacement of the Si-F bonds with the Si-H bonds was considered to be the back-bond-breaking reaction by water. Such a reaction between water and the surface Si-F was observed for the first time.

Nuclear Behavior in Artificially Induced Multi-Nuclear Cells of Dictyostelium discoideum: (cellular slime mold/Dictyostelium discoideum/Polysphondylium pallidum/artificially induced cell fusion/nuclear fusion).

The culture medium of the strain CK-8 of the cellular slime mold Polysphondylium pallidum contains a cell-fusion induction factor. Cells of the two opposite mating type strains NC-4 and HM1 of Dictyostelium discoideum were treated to induce cell fusion with the diluted fraction of CK-8 cultures, F2, which contains the factor and consequently numerous multinuclear cells were produced. NC-4 and HM1 usually fuse in the sexual cycle and form large multinuclear cells, called giant cells, which develop into macrocysts. These cells are very similar in morphology to the multinuclear cells produced following F2 treatment, however, the latter cells did not develop into macrocysts. In the sexually formed multinuclear cells, only two haploid nuclei fused to form a diploid nucleus and all others degenerate as previously reported. However, in the artificially produced multinuclear cells, no nuclear-fusion and degeneration took place. They stayed as heterokaryons and seem to lyse within 20 h incubation.

Reduction of interface-state density by F2 treatment in a metal-oxide-semiconductor diode prepared from a photochemical vapor deposited SiO2 film

A new technique for the reduction of the interface-state density Nss of a metal-oxide-semiconductor (MOS) diode has been developed. The SiO2 film was deposited on Si from Si2 H6 and O2 by direct photochemical vapor deposition (CVD) using vacuum ultraviolet (VUV) light of a D2 lamp. The new technique is a F2 treatment of the Si surface prior to the deposition of SiO2 film. Typically, 5% F2 gas diluted in He was introduced into the CVD chamber at 20 Pa for 5 min under UV light irradiation. The minimum value of the Nss was ∼5×109 cm−2 eV−1 at the Si midgap for the film deposited at 180 °C.