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Electrode materials are important factors affecting machining performances (MP) of electrical discharge machining (EDM). Experiments using different electrode materials were carried out in compressed air aim to realize MP of electrical discharge machining in gas (dry EDM). Experimental results show that a minimum pulse interval exists for given parameters and tool material. Calorific performances of tool materials are main influencing factors of MP on the condition of thorough deionization. Copper achieves the best MP in the experimental tool materials. Experimental results of different workpiece materials depict that material remove rate (MRR) and surface roughness (SR) value increase with increases of discharge energy. SKD61 steel achieves the highest MRR and SR value in the experimental materials. Material holding better performance of heat resistant, such as titanium alloy (TC4), achieves the lowest MRR.

Background It is very difficult and relatively unpredictable to preserve and restore severely weakened pulpless roots. To provide much needed benefit basis for clinical practice, this study was carried out to analyze the stress distribution in weakened roots restored with different cements in combination with titanium alloy posts. Finite element analysis (FEA) was employed in the study. Methods A pseudo three-dimensional model of a maxillary central incisor with flared root canal, theoretically restored with titanium alloy posts in combination with different cements, was established. The analysis was performed by use of ANSYS software. The tooth was assumed to be isotropic, homogenous and elastic. A load of 100 N at an angle of 45 degrees to the longitudinal axis was applied at the palatal surface of the crown. The distributions of stresses in weakened roots filled with cements of different elastic modulus were analyzed by the three-dimensional FEA model. Results Several stress trends were observed when the stress cloud atlas obtained in the study was analyzed. With the increase of the elastic modulus of cements from 1.8 GPa to 22.4 GPa, the stress values in dentin decreased from 39.58 MPa to 31.43 MPa and from 24.51 MPa to 20.76 MPa (respectively, for maximum principle stress values and Von Mises stress values). When Panavia F and zinc phosphate cement were used, the stress peak values in dentin were very small with no significant difference observed, and the Von Mises stress values were 20.87 MPa and 20.76 MPa respectively. On the other hand, maximum principle stress value and Von Mises stress value in cement layer increased with the increase of the elastic modulus of cements. Conclusions The result of this study demonstrated that elastic modulus was indeed one of the important parameters to evaluate property of the cements. Our three-dimensional FEA model study also found that the cement with elastic modulus similar to that of dentin could reinforce weakened root and reduce the stress in dentin. Thus, it may be a better choice for the restoration of weakened roots in clinical practice.

The existence of nickel (Ni) deficiency is becoming increasingly apparent in crops, especially for ureide-transporting woody perennials, but its physiological role is poorly understood. We evaluated the concentrations of ureides, amino acids, and organic acids in photosynthetic foliar tissue from Ni-sufficient (Ni-S) versus Ni-deficient (Ni-D) pecan (Carya illinoinensis [Wangenh.] K. Koch). Foliage of Ni-D pecan seedlings exhibited metabolic disruption of nitrogen metabolism via ureide catabolism, amino acid metabolism, and ornithine cycle intermediates. Disruption of ureide catabolism in Ni-D foliage resulted in accumulation of xanthine, allantoic acid, ureidoglycolate, and citrulline, but total ureides, urea concentration, and urease activity were reduced. Disruption of amino acid metabolism in Ni-D foliage resulted in accumulation of glycine, valine, isoleucine, tyrosine, tryptophan, arginine, and total free amino acids, and lower concentrations of histidine and glutamic acid. Ni deficiency also disrupted the citric acid cycle, the second stage of respiration, where Ni-D foliage contained very low levels of citrate compared to Ni-S foliage. Disruption of carbon metabolism was also via accumulation of lactic and oxalic acids. The results indicate that mouse-ear, a key morphological symptom, is likely linked to the toxic accumulation of oxalic and lactic acids in the rapidly growing tips and margins of leaflets. Our results support the role of Ni as an essential plant nutrient element. The magnitude of metabolic disruption exhibited in Ni-D pecan is evidence of the existence of unidentified physiological roles for Ni in pecan.

Serial culturing of organisms used for biological pest suppression often leads to detrimental genetic changes and loss of utility. We established that genetically homozygous inbred lines can deter beneficial trait decline in the entomopathogenic nematode, Heterorhabditis bacteriophora . Three inbred lines and the foundation population were serially cultured in the insect host, Galleria mellonella . Trait stability was evaluated by comparing serially cultured with non-cultured populations. Laboratory data indicated that serial culture of the foundation population (16 passages) resulted in more than a 30% loss in traits deemed beneficial for biological pest suppression i.e., virulence to an insect host ( Diaprepes abbreviatus ), reproductive capacity, heat tolerance (at 38 °C), and host-seeking ability. In contrast, the three inbred lines were impervious to decline in all beneficial traits. A greenhouse test targeting D. abbreviatus provided additional evidence that the biocontrol efficacy of the inbred lines remained stable during serial culture. Our results indicate that genetic factors played an important role in trait change, and creation of inbred lines may be a useful technique for maintaining beneficial traits.

Ozone (O(3)) is a significant component of atmospheric air pollution and produces detrimental effects in the lung. Although the mechanism of O(3)-induced lung inflammation and injury is unclear, the increased release of the proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) by lung cells following O(3) exposure may shed some light on this subject. To investigate the role of TNF-alpha in the O(3)-induced pulmonary insult, we intraperitoneally injected rats with either rabbit preimmune serum or rabbit antirat TNF-alpha 1 h prior to O(3) exposure. Approximately 12 h after the end of O(3) exposure the animals were sacrificed, the lungs lavaged, and tissue samples collected for expression of cytokine genes relevant to inflammation. The bronchoalveolar lavage fluid (BALF) was analyzed for albumin as a marker of pulmonary epithelial permeability changes and for fibronectin for its role in lung injury and repair. The lavage cells were collected, counted, and identified to quantitate the inflammatory response. Ozone exposure resulted in a significant increase in BALF albumin and fibronectin as compared to air-exposed controls and a significant increase in BALF polymorphonuclear leukocytes (PMNs). Antibody treatment produced a significant decrease in BALF albumin and PMNs as compared to O(3)-exposed rats given preimmune serum. Antibody treatment did not affect the BALF fibronectin concentration or the total cell count in the BAL. Tissue analysis for gene arrays revealed an activation of IL-1alpha, IL-6, and IL-10 in animals exposed to O(3). The gene expression was downregulated in animals treated with anti-TNF-alpha antibody prior to O(3) exposure. The results suggest a central role for TNF-alpha in the mechanistic pathways critical to lung inflammation. The significance of TNF-alpha in the inflammation and epithelial injury produced by ozone exposure reflects its overall contribution through modulation of other cytokines.

A new bacterial isolate, 00-50-5, from sunflower head extracts was identified as Bacillus thuringiensis (Bt) according to its morphology. Bt isolate 00-50-5 was highly active against the banded sunflower moth (BSM), Cochylis hospes Walsingham. A sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) 4-15% gradient gel of whole strain protein of 00-50-5 revealed six proteins with molecular masses (M r ) of 133, 80, 60, 27, 15, and 14 kDa. SDS-PAGE of pH 4.2-precipitated proteins (PP) or activated proteins formed by adding the BSM larval gut protease at 1:50 (wt/wt, protease/PP) showed five bands, including two major proteins of M r 60 kDa and 27 kDa, and three small peptides of M r 15, 13, and 7 kDa. The BSM larval gut protease was able to completely digest the proteins when present at a high ratio (10:1, wt/wt, protease/PP). The 60- and 27-kDa proteins could be digested by subtilisin Carlsberg at ratios of 1:50 or 1:1 (wt/wt, protease/PP), but neither BSM larval gut protease nor trypsin was effective at the same ratios. Three small peptides of M r 15, 13, and 7 kDa were digested by the gut protease at a ratio of 1:1 (wt/wt). The N-terminal sequence of 1-31 amino acid residues for the 27-kDa protein showed 96.7% homology to a 31-amino acid fragment from camelysin, a protease from B. cereus, indicating that the 27-kDa protein may be a camelysin and a novel active protein against BSM.

SUMMARYA new Bacillus thuringiensis strain, 00-50-5, exhibited an unusually high activity against banded sunflower moth (BSM) Cochylis hospes, which is an economically important pest of cultivated sunflowers in North America. The strain was fermented with a modified commercial medium in a bioreactor. This was a successful trial for production of 00-50-5 on a larger scale. After fermentation, the yield of dried powder was 5.8 g/l broth. In the laboratory assays, the LC50 (lethal concentration required to kill 50% of targets) of the dried powder was 0.5 μg/ml 3 d after exposure against four instars of BSM. Some practically useful conditions and parameters for the fermentation operating procedure and methods for harvesting were determined.

Multi-fold refractive seismic exploration is such a method that is generally used to trace the geological structural interfaces when the reflected seismic section is not good or used to trace the base structural configuration and to study the base interface. This paper will discuss the theory and method of imaging underground refractors with the refractied seismic waves in the refractied seismic data, based on the refraction theory. The method was called common depth refraction segments stack imaging method. The velocity analysis steps and NMO processing of the refractive wave by use of the theory and the method will also be given. A better imaging method, the common depth refractive point stack imaging method, will be proposed in the paper. Finally, the exactness and the practicality of the given methods will be verifired by processing model example and real data.

Commercial enzymes and insect gut juice at various concentrations were used to digest Bacillus thuringiensis subsp. sotto Cry1Aa protoxin and examine the fragmentation pattern and effect on insecticidal activity. Trypsin at both high (5 mg/mL) and low (0.05 mg/mL) concentrations converted protoxin to toxin with no difference in insecticidal activity against Bombyx mori larvae. In both cases, the toxin protein had an apparent Mrof 58.4 kDa (SDS-PAGE). Active toxin of identical Mrwas also produced with low concentrations of Pronase and subtilisin, but at high concentration, it was degraded into two protease-resistant fragments of apparent Mr31.8 and 29.6 kDa, and exhibited no insecticidal activity. Sequencing data established the primary cleavage site to be in domain II, the receptor-binding region of the toxin, in an exposed loop between two beta-sheet strands. Fragmentation was not observed, however, when the digests were analyzed by native protein techniques, but rather the toxin molecule appeared to be intact. The amount of activated toxin produced by Choristoneura fumiferana gut juice was markedly reduced when the gut-juice concentration was increased from 1 to 50% and correlated with a loss in insecticidal activity. However, no lower Mrprotease-resistant fragments were evident in the SDS-PAGE of these digests.Key words: Bacillus thuringiensis endotoxin, Lepidoptera, proteolytic enzymes, insect gut juice, activation, digestion.

Monomeric isocitrate dehydrogenase was expressed in Corynebacterium glutamicum cells harboring pEK-icdES1, a plasmid carrying the gene for the enzyme. Two- to three-fold higher expression levels of the recombinant enzyme were observed in such cells when grown in fermentors, compared to those grown in shaker incubators. The enzyme was purified to homogeneity by ammonium sulfate fractionation, Sephadex G-150 gel filtration, FPLC Mono Q anion-exchange chromatography, and affinity gel chromatography. Approximately 4 mg of 98% pure recombinant enzyme was obtained per liter of bacterial culture. Our results also include optimum buffer conditions for purification and storage of the enzyme.

Interfacial interactions of several commercial perfluoropolyether (PFPE) and aromaticmodified lubricants with silicon oxide or carbon substrates were investigated through contact angle measurement, dipping tests, fluorescence spectroscopy and contact-start-stop testing. All commercial lubricants that have not been thermally treated are displaced from the solid substrate by contact with water. Contact angles of water on ZDOL, a PFPE doubly-terminated with hydroxyl groups, spun on silicon and carboncoated wafers were measured as a function of thermal annealing treatment. The adhesion of commercial lubricants to such previously thermally-bonded layers is stronger than to the bare silicon wafers. The thermal reaction of ZDOL on silica gel and carbon was investigated by thermogravimetric analysis and FTIR. The thermal reaction takes place when the baking temperature exceeds 70°C; at least part of this surface-bonding involves condensation of terminal hydroxyl groups with isolated surface silanols. Fin...

To research the role of lymph tracers to protect parathyroid in surgery for papillary thyroid carcinoma.Patients with papillary thyroid carcinoma who met selected criteria were enrolled in this study. Patients were divided into carbon nanoparticle group, methylene blue group, and conventional surgery group.No significant complication occurred in the patients of carbon nanoparticle and methylene blue groups. In carbon nanoparticle group, methylene blue group and conventional surgery group, the mean numbers of parathyroid glands detected during surgery were 3.1 ± 0.3, 2.9 ± 0.4 and 2.3 ± 0.3 (F = 3.78, P0.01) , the rates that parathyroid was cut mistakenly were 1.37% (2/146) , 2.62% (2/97) and 7.14% (6/84) respectively (χ(2) = 17.372, P0.05) ; and the incidence of postoperative hypocalcemia were 10.4% (5/48) , 9.1% (3/33) and 17.5% (7/40,χ(2) = 0.671, P = 0.037) .Thyroid lymphography technique is helpful to protect from the injury to the parathyroid glands in surgery.

Hypersonic vehicle's nonlinear dynamics system is highly nonlinear, multivariable coupled and includes uncertain parameters. To solve this problem, a new back stepping controller is designed based on nonlinear disturbance observer (NDO). The NDO is used to observe the disturbance of the system and the limitation of the disturbance can be unknown. Theoretical analysis is done to validate that the system satisfy control requirements and is uniformly ultimately bounded. The simulation results also show that the developed method is effective and deals with the problem of uncertain factors preferably.

To investigate the expression of androgen receptor (AR) and hepatitis B virus X protein (HBx) in hepatocellular carcinoma (HCC), and analyze the relationship between AR and HBx expressions.Tumor tissues and peritumoral tissues of 83 HBV-associated HCC cases were investigated in this study. Fourteen cases of HBV-negative HCC and 13 cases of hemangioma peritumoral tissues were considered as control. AR and HBx mRNA levels were determined by quantitative fluorescence real-time RT-PCR and their protein levels were assayed by Western blot. The expression of AR and HBx proteins in tissues were examined with EnVision immunohistochemical staining. The methylation status of AR promoter was determined using methylation-specific PCR (MSP).Both expression levels of AR mRNA and protein of the peritumoral tissues were significantly higher (0.17) than that of tumor tissues (0.09) in HBV-associated HCC (P0.01), but such a difference was not found in HBV-negative HCC (0.06 vs. 0.07, P0.05). The level of AR expression in peritumoral tissues was associated with tumor differentiation in HBV-associated HCC. AR mRNA and protein levels of peritumoral tissues in HBV-associated HCC were significantly higher than that in HBV-negative HCC and hemangioma (all P0.05). In the tumor tissues, HBV-associated HCC had significantly higher AR expression than HBV-negative HCC at mRNA level (P0.05), but not at protein level. Spearman rank correlation analysis showed that the AR mRNA or AR protein levels were positively correlated with HBx in both tumor and peritumoral tissues in HBV-associated HCC, but the expressions of AR and HBx were not associated with AR promoter methylation status. The relative expression levels of AR mRNA and protein in the HBV-associated peritumoral tissues were negatively correlated with tumor differentiation (r = -0.213, P0.05; r = -0.313, P0.05), the higher the AR expression, the poorer differentiation. But this correlation of AR mRNA and protein was not shown in the hepatocellular carcinoma tissues.HBx may enhance AR expression in HBV-associated HCC, but AR promoter demethylation maybe not been involved in its main mechanism. An increased AR expression is probably an early event during the development and progression of HBV-associated HCC, and AR expression in the peritumoral tissue is correlated with HBV-associated HCC differentiation. AR may play different roles in HBV-associated HCC and HBV-negative HCC.

In the previous paper we discussed the relationship between blob defect count and the receding angle of a resist surface after development with an alkaline developer solution. This paper summarizes additional test results from our continued efforts in developing next generation embedded barrier layer (EBL) materials that render a resist film with even higher receding angle to further facilitate high speed and high acceleration scanning. How to reach a higher receding angle without sacrificing a low post development receding angle is also discussed in this paper. The ability for an EBL material to switch from a high receding angle to a receding angle of lower than 20° upon development is considered a very important attribute of an EBL, which is the key to reduce blob defect count by ensuring good dynamic wetting of a resist surface to DI water during a post development rinsing step. Resist formulations with different receding angles were studied for lithography performance and defectivity under different process conditions with varying wet processes. Both good lithography performance and low defectivity were obtained for contact hole resists including those with a surface receding angle of 78°.

A theoretical model for calculating the thermal IR radiation of different backgrounds was developed. The model framework consists of a system of steady-state energy budget equations describing the energy interaction which takes place within the underlying scene. Knowing the thermal characteristics and the driving meteorological variables, we established and solved the equation for the surface temperature. The model was applied to natural and man-made backgrounds over a diurnal cycle. Simulated surface temperatures of different backgrounds were compared with each other in the same environmental conditions, which show that the surface temperatures of artificial surfaces are well above that of natural surfaces. Between the natural surfaces, there is a distinct difference between vegetation and soil. To obtain a better model evaluation, the temperature-moisture coupling in the surface layer was considered.

This study was purposed to investigate the intercellular cell adhesion molecule-1 (ICAM-1) gene K469E (A/G) (rs5498) and K56M (A/T) (rs5491) single nucleotide polymorphisms (SNP) and soluble ICAM-1 (sICAM-1) levels in plasma in three Chinese populations of Yugur, Tibetan and Han nationalities, to analyze comparatively the genotypes and allele frequencies distribution in different ethnic groups, and to explore the effects of ICAM-1 K469E and K56M polymorphism and sICAM-1 levels in plasma. EDTA-anticoagulant venous blood from Yugur(327 cases), Tibetan (400 cases) and Han (126 cases) people was collected, the DNA was extracted by using whole blood genomic DNA extraction kit, DNA SNP were analyzed by PCR-RFLP, genotype was judged by gel scan imaging system after agarose gel electrophoresis, the gene sequence was determined and the distribution of ICAM-1 genotypes and allele frequencies were compared among different ethnic groups, besides, the group representativeness was tested via the Hardy-Weinberg genetic equilibrium. Finally, the human sICAM-1 plasma levels were detected by using human ICAM-1 ELISA kit. The results showed that DNA sequencing result was consistent with PCR-RFLP analysis. In Yugur, Tibetan and Han nationalities, the KK, KE and EE three genotypes at ICAM-1 K469E gene locus were detected, the genotype distribution was not statistically significantly different, while the K, E allele frequency distribution was statistically significantly different (P0.05). Both of genotype and allele frequency distribution between Yugur, Tibetan and Han nationalities were statistically significantly different (P0.05). In K56M site only KK, KM two genotypes were detected, but the MM genotype was not detected in the three ethnic groups; the difference of two genotypes and K, M allele frequencies between Yugur and Han population was statistically significantly different (P0.05). Among three ethnic groups, the sex ratio and age distribution of K469E, K56M genotypes and allele frequencies of ICAM-1 gene were not significantly different, and distribution was in accordance with Hardy-Weinberg genetic equilibrium (P0.05). The plasma sICAM-1 level at ICAM-1 K469E allele locus in K individuals [(253 ± 122), (185 ± 97) µg/L] was higher than that at non-K allele [(145 ± 110) µg/L, P0.01]; the plasma sICAM-1 level of ICAM-1 K56M sites with KK genotype [(253 ± 122) µg/L] was higher than that of the KM genotypes [(168 ± 103) µg/L, P0.01]. In Yugur and Tibetan groups, the plasma sICAM-1 levels [(224 ± 80), (214 ± 111) µg/L] were higher than that in the Han group [(175 ± 125)µg/L, P0.05]. Pairwise comparison indicated that the plasma sICAM-1 levels between Yugur and Han group were statistically significantly different (P0.01), that was significantly different between Tibetan and Han group (P0.05). It is concluded that in Yugur, Tibetan and Han population, the genotypes and gene frequencies of two amino acid sites K469E and K56M in ICAM-1 were KK/KE-type, KK-type and K allele, moreover, the ratio of them in Yugur and Tibetan group was higher than that in Han, while there is not significant difference in sex ratio and age distribution, therefore, ICAM-1 genotype and allele frequency distribution in this study had ethnic representativeness. ICAM-1 gene K469E and K56M polymorphisms were likely to affect the plasma sICAM-1 expression level. K469E gene K allele may be a genetic risk factor, while K56M gene M allele a may be genetic protective factor for some diseases.

The aim of this study was to investigate the similarities and differences of A1381T (rs216311) and -1793G/C (rs7966230) single nucleotide polymorphisms (SNP) in Chinese Yugur, Tibetan, and Han nationalities and their influence on plasma vWF concentration in order to explore the sensitivity of these 3 nationalities to vWF-related diseases. Peripheral venous blood was obtained from 322 Yugur, 399 Tibetan, and 120 Han healthy people. The DNA were then extracted. vWF gene A1381T and -1793G/C polymorphisms were analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequenced when it was necessary. The vWF:Ag level in plasma was determined by ELISA. The results showed that the genotype distribution of vWF gene at both A1381T and -1793G/C loci in Yugur, Tibetan and Han nationalities was different with statistically significance (P0.05). GG genotype of A1381T locus accounted for 69.9% in Yugur nationality, which was much higher than 56.6% and 53.3% in Tibetan and Han nationalities respectively(P0.01); AA genotype of A1381T locus expressed a low level of vWF in plasma. For the -1793G/C locus, the proportion of CG genotype in Yugur was much higher than that in Han, CC genotype expressed a high level of vWF in plasma. The plasma vWF levels with different nationalities and the polymorphism of vWF gene were significantly different. It is concluded that the polymorphisms of vWF gene at both A1381T and -1793G/C loci in Yugur, Tibetan and Han are significantly different; the polymorphism of vWF gene influences the plasma vWF level; the plasma vWF levels in Yugur and Tibetan are significantly higher than that in Han, which may be associated with the living environment and habits.

To explore the role and mechanism of motilin in colonic motility disorder.A total of 20 male Wistar rats (180 - 200 g) were randomly divided into 2 groups: water avoidance stress (WAS, n = 10) and sham water avoidance stress (SWAS, n = 10). Rats were exposed to 1 h WAS or SWAS daily for 10 consecutive days. Motilin in plasma was measured by enzyme-linked immunosorbent assay (ELISA). Proximal colon circular smooth muscle cells (PCSM) were isolated by enzymatic digestion and L-type calcium currents (ICa(L)) recorded by patch-clamp techniques.The fecal pellets during 1 h WAS significantly increased (5.4 ± 1.0 vs 2.4 ± 0.7, P0.01, n = 10). The motilin in plasma had significant difference between WAS rats and SWAS rats ((135 ± 35) vs (89 ± 24) pg/ml, P0.01, n = 10). The ICa(L) of two rats had no significant difference. But 6 × 10(-5) mmol/L motilin increased ICa(L) more in WAS than in SWAS rats at 0 mV ((1.6 ± 0.4) vs (1.0 ± 0.3) pA/pF, P0.05, n = 10).WAS leads to elevated motilin levels in plasma and active L-type Ca(2+) channels in colon. And it contributes to colonic motility disorder.

Somatic gene V617F mutation in JAK2 is a critical molecular and biological indicator to diagnosis of chronic myeloproliferative disease (MPD). This study was aimed to investigate the genetic background of V617F mutation in 46/1 gene haplotype in Chinese MPD patients, and the frequencies of 46/1 gene haplotype and V617F mutation in three nationalities of Chinese populations. Peripheral blood or bone marrow samples of 150 V617F mutation positive MPD patients, 123 V617F mutation negative MPD patients, 124 healthy Han individuals, 395 healthy Tibetan individuals and 315 healthy Yugu individuals were collected. The allele-specific multiplex PCR method was established, the presence or absence of V617F mutation, the presence or absence of 46/1 haplotype, and the relationship between V617F and 46/1 haplotype were easily identified by agarose gel image. The results showed that the V617F mutation located in the 46/1 haplotype of 88 cases (58.67) among 150 V617F-positive MPD cases. In 814 Chinese healthy individuals including Han, Tibetan, Yugu nationalities, the frequency of the 46/1 gene haplotype was 38.37 without difference in the frequency among different nationalities, and no V617F mutation was found in Chinese healthy populations, The frequency of the 46/1 gene haplotype was 43.09 in V617F mutation negative MPD patients and was 69.33 in V617F mutation positive MPD patients, the latter was obviously higher than former and than that in healthy Han individuals. In conclusion, a multiplex PCR method has been developed that is simple and useful to identify V617F mutation in JAK2 gene and its relationship to the 46/1 haplotype. In more than half of Chinese V617F-positive MPD patients, the V617F mutation locates in 46/1 haplotype in JAK2. The frequencies of 46/1 haplotype are statistically insignificant among Han, Tibetan and Yugu nationality populations.

In 193nm immersion lithography, immersion top coat was the first proposed technique for preventing the leaching of photoresist (resist) components, such as photoacid generator (PAG) and quencher base, into the immersion fluid (DI water). In this approach, the top coat is coated onto a resist film in a separate step including coating the top coat film and baking the film. This approach certainly adds extra cost to the device manufacturing and incurs reduced throughput as compared to the dry lithography process. The embedded barrier layer (EBL) technology1-5 developed at Dow Electronic Materials has been demonstrated to be a revolutionary approach, in which a suitable EBL material is formulated into an existing resist, and in a spin coating process the EBL material comes to the resist surface to forms a leaching barrier in situ. This approach has now been widely accepted and implemented in the integrated circuit manufacturing industry for replacing the conventional immersion top coat process. In addition to being an excellent leaching barrier, EBL materials, in general, result in a resist surface with a high receding angle for water. This property makes the EBL approach more desirable in topcoat free immersion lithography, since it allow for the latest scanners to perform at their maximum scan speed without generating watermark defects. For immersion lithography, the most important issue for mass production is defectivity control. This is true for both top coat and topcoat free approaches. In the top coat approach, the formulation optimization for both top coat and resists was extensively involved for this technique finally to reach an acceptable defectivity level for mass production of semiconductor devices. As a later developed technology, the EBL approach has gone through a series of research and development stages particularly in material innovation to reach the same low defectivity level as that of an immersion top coat process. After achieving the target of low defectivity in lithography, the challenges left to the EBL approach were to solve high defectivity in bulk exposed and bulk unexposed regions, which became prominent in both bright field and dark field lithographic applications. To solve the high defectivity issues, a thorough understanding of the blob defect formation mechanism was imperative. In this paper, the defect formation mechanism in both bulk exposed and unexposed regions is proposed, and this proposed mechanism is applicable not only to the EBL approach but also to the immersion top coat approach in general.

In order to improve the accuracy of the red jujube disease recognition, the study establishes a recognition model of disease severity, with the improved Particle Swarm Optimization Back Propagation(PSO-BP) neural network combined with color and geometry characteristic parameters of red jujube tree leaf disease spot. Mutation operator and linear decrease inertia weight are combined to improve the performance of PSO, a new improved PSO is formed to get optimal neural network weights and thresholds. The experimental results show that the accuracy and performance of red jujube disease recognition model is improved. The slight, general and serious disease reached separately 87.6%, 82.4% and 94.0%.

Field synergy between the molten steel flow field and the temperature distribution was analyzed at first in this paper. It shows when the synergy angle between the molten steel flow field and the temperature gradient field is more than90ia in the tundish, the molten steel temperature distribution is more homogeneous and the synergy number is smaller. Then the flow fields and temperature distributions in the one-strandtundish established with different flow controls were numerically calculated. The results show that the synergy angles are more than 90ia in the back-flow zones and gradually decrease as far from the back-flow zones till to almost 0ia. The temperature gradient are large in the zones near the tundish wall boundary and around the stopper. When the tundishequipped with a turbulence inhibitor, a weir and a dam, the synergy angles are morn than 90ia in the majority of molten steel flow domains, the temperature distribution is even. So, the established controls in the tundish can modifiy the flow characteristics and temperature distribution.

In this paper we investigate fundamental resist properties to enhance resolution and focus margin for immersion contact hole patterning. Basic chemistry factors have been used to manipulate the iso-focal region (the region of smallest critical dimension variation through focus) of the photoresist and study the impact on resolution and focus margin for small isolated contact holes. Acid diffusion length is one of the key factors investigated, which can be controlled by polymer, PAG, quencher, bake temperature and bake time. The various criteria investigated for this study were: focus and exposure latitude for dense L/S, dense C/H and semi-dense C/H. The effect of manipulating the acid diffusion of the photoresist on imaging small contact holes was verified using ultra-high NA immersion imaging at 1.35 NA.

Entomopathogenic nematodes are used for biological control of insect pests. A method for improved cryopreservation of infective juvenile stage nematodes has been developed using Steinernema carpocapsae and Heterorhabditis bacteriophora. Optimum survival for both species was achieved with 12,000 infective juveniles/ml in glycerol and 7,500/ml in Ringer's solution. For S. carpocapsae, maximum survival also was observed with 60,000 infective juveniles/ml in glycerol and 25,000/ml in Ringer's solution. These concentrations resulted in 100% post-cryopreservation survival of S. carpocapsae and 100% retention of original virulence to Galleria mellonella larvae. This is the first report of achieving 100% survival of an entomopathogenic nematode after preservation in liquid nitrogen. Maximum survival of H. bacteriophora following cryopreservation was 87%.

With the decrease in pitch in the line/space patterning, micro-bridge defects have become the major defect in the immersion applications. As a result, reducing micro-bridge defect count is one of the key tasks for mass production of semiconductor devices using immersion lithography for both topcoat and non-topcoat processes. In this paper, we focus on the non-topcoat approach particularly the embedded barrier layer (EBL) technology1-4. The advanced EBL materials discussed in this paper have demonstrated to be able to reduce total defect including micro-bridge defect count to the same level as that of a topcoat process. It was found that the developer solubility of the EBL materials in both bright and dark fields and the contrast of the EBL materials play important roles for reducing overall defectivity.

At the 32nm node, the most important issue for mass production in immersion lithography is defectivity control. Many methods have been studied to reduce post-exposure immersion defects. Although a topcoat process demonstrates good immersion defect prevention, a topcoat-less resist process is an attractive candidate for immersion lithography due to cost reduction from a simplified process. In this paper we took the innovative approach of chemically designing an internal self-assembling barrier material that creates a thin embedded layer which functions as a topcoat. Data will be presented on this novel self assembly concept, illustrating the control of leaching, contact angle and immersion defects. Several optimized process flows with non-topcoat resists were also studied to decrease the amount of immersion defects. This study was used to verify the capability of a topcoat-less immersion process to achieve the low-defectivity levels required for 32nm node production.

The introduction of double patterning and double exposure technologies, especially in combination with hyper NA, increases the importance of wafer topography phenomena. Rigorous electromagnetic field (EMF) simulations of two beam interference exposures over non-planar wafers are used to explore the impact of the hardmask material and pattern on resulting linewidths and swing curves after the second lithography step. Moreover, the impact of the optical material contrast between the frozen and unfrozen resist in a pattern freezing process and the effect of a reversible contrast enhancement layer on the superposition of two subsequent lithographic exposures are simulated. The described simulation approaches can be used for the optimization of wafer stack configurations for double patterning and to identify appropriate optical material properties for alternative double patterning and double exposure techniques.

To research the erythrocyte immunoregulation effects of Patrinia scabra extracts by macroporous adsorptive resins on mice burdened transplanted tumor.Extracts of Patrinia scabra Bunge were separated by macroporous adsorptive resins, ingredients were analysised. Mice burdened transplanted tumor were given extracted drugs. Life prolongation rate was observed, erythrocyte immunologic function and the CD35, CD44s contents of red blood cell were evaluated.Polysaccharide and saponin accounted for 8.4% and 48.4%. Extracts could porolong life expectancy of mice, improve erythrocyte immunolgic function and increase the CD35 and CD44s contents of red blood cell.Extracts of Patrinia scabra Bunge by macroporous adsorptive resins have erythrocyte immunoregulation effects on mice burdened transplanted tumor.

The UV absorption and fluorescence spectra of trans- and cis-1,4-di(2-naphthyl)cyclohexane (DNCH) in water-organic binary mixtures have been investigated. In organic solvents, they only emit monomer fluorescence of the naphthyl chromophore. However, in the mixed solvents, the fluorescence spectra were dominated by dimer emission, and the UV absorption spectra are significantly red-shifted. This suggests that in the binary mixtures the hydrophobic interaction forces DNCH molecules to aggregate, and inside the aggregate the naphthyl groups of different DNCH molecules overlap and interact with each other to form an intermolecular dimer. The effect of temperature on the fluorescence spectra was studied.

OBJECTIVE To evaluate the effects of Fuzheng Yiliu Granules (FZYLG) on apoptotic rate and mitochondrial membrane potential (Delta psi m) of hepatocellular carcinoma cell line H22 from mice. METHODS Forty-eight mice inoculated with H22 cells were randomly divided into four groups: untreated group, cyclophosphamide-treated group, high-dose FZYLG-treated group and low-dose FZYLG-treated group. After 14 days of corresponding treatment, H22 cells in each group were stained with propidium iodide, and the apoptotic rates were detected by flow cytometry (FCM). The rhodamine 123 was used as a fluorescence probe to label the H22 cells, and the fluorescence intensities were observed with laser scanning confocal microscope. The fluorescence intensity of H22 cells indicated the Delta psi m of H22 cells. RESULTS FZYLG could significantly increase the apoptotic rate while reduce the Delta psi m of H22 cells from mice as compared with those in the untreated group. CONCLUSION The antitumor effects of FZYLR on H22 cells from mice are related to decreasing the Delta psi m and then inducing the apoptosis of the H22 cells.

A combination of simulation, resist modification and process optimization were used to develop production worthy dry 193nm lithography processes, suitable for the metal trench layers of 65nm node logic devices. The important performance characteristics of a back-end metal trench layer are through-pitch proximity bias, lithographic latitude and ultimate resolution. Simulation results suggested that a moderate annular illumination setting balances proximity bias against resolution at the forbidden pitch, yielding a good overall through-pitch common process window. Resist material optimization through resin, PAG (photo-acid generator) and base quencher modification improves proximity bias and results in excellent lithographic performances of good LER (line edge roughness), low MEF (Mask Error Factor) and wider process latitude. To investigate extendibility to 45nm node applications, the immersion compatibility of the optimized resist with several top coats are reported.