现代转型视域下的乡土塑形与人性勘探——评刘伟宏的长篇小说《大原》

百万字的《大原》全息性地展现出乡土中国的西北一隅历史转型的时代阵痛和心灵惊悸。它的史诗气质、恢宏格局和微观意义上的细部塑形都暗合了文化地理学与文化诗学的勘探路径,这种在多元动态的时空语境中重提地方性“知识”的审美想象和文化寻根行为,虽然在一定程度上呈现为文化保守主义的后撤姿态,但对深刻反思全球化坐标中的身份认同和人性迷失,具有独特的艺术参照价值。它关于民族性与现代性的审美钩沉、乡土怀旧与“人学”建构的话语考辨,以及自身的完成性与未完成性的复杂存留都应值得关注,也将会产生“复数”而“及物”的意义。

Optimal Control for Age Distribution and Weighted Size Competitive Species in a Polluted Environment

In the paper,we study an optimal control for a system representing a competitive species model with fertility and mortality depending on a weighted size in a polluted environment.A fixed point theorem is applied to obtain the existence and uniqueness exhibited by a non-negative solution of above mentioned model.A maximum principle helps to carefully verify the existence of the optimal control policy,and tangent-normal cone techniques help to obtain the optimal condition specific to control issue.

In-situ investigation of atmospheric corrosion behavior of bronze under thin electrolyte layers using electrochemical technique

The atmospheric corrosion behavior of bronze under thin electrolyte layer （TEL） with different thicknesses was monitored using cathodic polarization curves, open circuit potential （OCP） and electrochemical impedance spectroscopy （EIS）. Cathodic polarization result indicates that the cathodic limiting current density increases with decreasing the TEL thickness. EIS result shows that the corrosion rate increases with decreasing the TEL thickness at the initial stage because the corrosion is dominated by the cathodic process, whereas after long immersion time, the corrosion degree with the TEL thickness is in the sequence of 150 μm 〉 310 μm〉 10μm ≈ bulk solution 〉 57 μm. The measurements of OCP and EIS present in-situ electrochemical corrosion information and their results are in good agreement with that of physical characterizations.

Identification of Wheat-Barley 2H Alien Substitution Lines

The genetic constitution of fifteen materials derived from the cross wheat (Triticum aestivum L. cv. 'Chinese Spring') X barley (Hordeum vulgare L. cv. 'Betzes') was analyzed, and six disomic alien substitution lines were screened by GISH. The chromosome configurations in pollen mother cells at meiotic metaphase I (PMCs M I) of F, from each disomic substitution line respectively crossed with double ditelocentric lines 2A, 2B and 2D of 'Chinese Spring' were observed, and a set of wheat-barley disomic alien substitution lines 2H(A), 2H(B) and 2H(D) were obtained. The RFLP analysis with the probe psr131 on the short arm of wheat homeologous group 2 combining with four restriction enzymes were carried out. The results indicated that the probe psr131 could be used as molecular marker to tag the barley chromosome 2H. The barley chromosome 2H had good genetic compensation ability for wheat chromosomes 2B and 2D in vitality and other agronomic characters. The result of testing seed was that the wheat appearance starch quality had been changed from the half-farinaceous of 'Chinese Spring' to the half-cutin of substitution lines by transferring the barley chromosome 2H to wheat.

Chromosomal Localization of Genes bz1,bz2 in Maize by Using Ultra-sensitive FISH with Tyramide Signal Amplification(TSA-FISH)

It has been reported that endosperm undergoes programmed cell death (PCD) during maize kernel development.Both bz1 (bronze ) and bz2 are anthocyanin biosynthetic genes,and related to development of aleuronic layer of maize seeds.Tyramide signal amplification fluorescence in situ hybridization (TSA FISH) is a novel and high sensitive FISH technique,which is suitable for routine application in plant cytogenetic research.Using this technique,we physically mapped the bz1 gene onto the short arm of chromosome 9 and the long arm of chromosome 1;the percentage distances from centromere to hybridization site were 40.2,75.4 respectively,and the bz2 onto the long arm of chromosome 1 and the short arm of chromosome 5;the percentage distances from centromere to hybridization site were 21.6,15.3 separately.The TSA FISH techniques of small low copy DNA sequences for plants are discussed.

A new fuzzy edge detection algorithm

Based upon the maximum entropy theorem of information theory, a novel fuzzy approach for edge detection is presented. Firstly, a definition of fuzzy partition entropy is proposed after introducing the concepts of fuzzy probability and fuzzy partition. The relation of the probability partition and the fuzzy c-partition of the image gradient are used in the algorithm. Secondly, based on the conditional probabilities and the fuzzy partition, the optimal thresholding is searched adaptively through the maximum fuzzy entropy principle, and then the edge image is obtained. Lastly, an edge-enhancing procedure is executed on the edge image. The experimental results show that the proposed approach performs well.

The application of formative assessment in college oral English teaching

Teaching assessment is one of the most important components of college English teaching. The traditional assessment system over emphasizes the summative assessment, which used examinations as the main assessment method. Formative assessment focuses on the process assessment during the practice of teaching. It is integrated in the teaching and learning process and cannot be separated as evaluation. The formative assessment aims to confirm the students＇ potential, develop their ability in study and strengthen the students＇ confidence and the spirit of cooperation. It is also a method intended to generate feedback on performance to improve and accelerate teaching and learning effectively. Based on some theories, this paper states the importance of the application of formative assessment in college oral English teaching. It also introduces some principles and measures to apply this assessment. The reasonable and effective application can promote college oral English teaching.

Screening of Deltamethrin Resistant Strain of Bombyx Mandarina

[ Objective ] The aim of the study was to explore the resistance development of deltamethrin through selection of dettamethrin resistant strain of wild silkworm （ Bombyx Mandarina）, thus providing the basis for scientific pesticide application and resistance management. [ Method] The wild silkworms collected from three different regions were reared indoors, and the sensitivity of their parents to deltamethrin was detected by topical application. The larvae in each generation were treated with deltamethdn in median lethal dose or so by.topical application. The mortality of larva was analyzed for the establishment of toxicity regression equations and the calculation of the multiple or increased multiple of deltamethdn resistance.[Result] After the Qidong Bornbyx Mandarina （YQD） fed with mulberry leaves were selected for three generations indoors, the multiple of deltamethdn resistance of F, was 14.26, 1.2 times as great as that of Fo ; after the Bombyx Mandarina from mulberry garden of Soochow University （YSD） fed with mulberry leaves were selected for three generations indoors, the multiple of deltamethrin resistance of F4 was 16.48, 1.9 times as great as that of Fo ; after the Wujiang Bombyx Mandarina （YWJ） fed with artificial diets were selected for three generations indoors during six generations, the multiple of deltamethrin resistance of Fe was 18.67, 1.2 times as great as that of Fo. [ Conclusioa] With the selection in same dose, the resistance multiple of YSD increases more rapidly than that of YQD; under double selection of artificial diets and insecticide, the resistance multiple of YWJ increases more slowly than that of YQD.

Bioinformatics Analysis on B cell Epitopes of Rice Allergen RAG1

[Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary structure of RAG1 was predicted by DNAStar Protean software with Gamier-Robson program, Chou-Fasman program and Karplus-Schulz program; the B cell epitopes of RAG1 was predicted with the Kyte Doolittle hydrophilic program, Emini surface accessibility program and Jameson-Wolf antigenic index program. [Result] The predictions on secondary structure and B cell epitopes showed that the regions of 33-44, 119-129, 155-163 were the dominant B cell epitopes. [Conclusion] This study predicted the potential dominant B cell epitopes in rice allergen RAG1 by comprehensive use of multi-methods and multi-parameters, and provided a theoretical basis for further researches on identification, antigen modification and epitope vaccine design of RAG1 B cell epitopes.

Portal vein embolization for induction of selective hepatic hypertrophy prior to major hepatectomy: rationale,techniques, outcomes and future directions

The ability to modulate the future liver remnant(FLR) is a key component of modern oncologic hepatobiliary surgery practice and has extended surgical candidacy for patients who may have been previously thought unable to survive liver resection. Multiple techniques have been developed to augment the FLR including portal vein embolization(PVE), associating liver partition and portal vein ligation(ALPPS), and the recently reported transhepatic liver venous deprivation(LVD). PVE is a well-established means to improve the safety of liver resection by redirecting blood flow to the FLR in an effort to selectively hypertrophy and ultimately improve functional reserve of the FLR. This article discusses the current practice of PVE with focus on summarizing the large number of published reports from which outcomes based practices have been developed. Both technical aspects of PVE including volumetry, approaches, and embolization agents; and clinical aspects of PVE including data supporting indications, and its role in conjunction with chemotherapy and transarterial embolization will be highlighted. PVE remains an important aspect of oncologic care; in large part due to the substantial foundation of information available demonstrating its clear clinical benefit for hepatic resection candidates with small anticipated FLRs.

Using a linear array to estimate the velocity of underwater moving targets

A new method uses a linear array that takes advantage of underwater physical sound fields to estimate the velocity of an underwater moving target. The mathematical model was established by considering the geometric relationship between the moving target installed with only two transducers to radiate sound of different frequencies and the linear array. In addition, deterministic maximum likelihood and signal phase matching algorithms were introduced to effectively find the directions of arrival （DOAs） of the sound sources of the two transducers installed on the target. Factors causing velocity measurement errors were considered. To track the target, a linear array with a compass, a pressure transducer, a signal conditioner and a digital recorder was configured. Relevant requirements for the array parameters were derived. The simulation showed that a 16-element array with an aperture of less than lm can measure velocity with relative error of no more＇, than 4% when including typical system errors. Anechoic pool and reservoir experiments confirmed these results.

Jianpi Qingchang decoction alleviates ulcerative colitis by inhibiting nuclear factor-κB activation

To investigate the therapeutic effect of Jianpi Qingchang decoction (JPQCD) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice.METHODSC57BL/c mice were injected intragastrically with 5% DSS instead of drinking water for 7 d, and their body weight, diarrhea severity and fecal bleeding were monitored, while the mice in the control group were treated with standard drinking water, without DSS. After 7 d, the DSS drinking water was changed to normal water and the DSS group continued with DSS water. The control and DSS groups were given normal saline by intragastric injection. The 5-aminosalicylic acid (5-ASA) group was treated orally with 5-ASA at a dose of 100 mg/kg daily. The JPQCD group was treated orally with JPQCD at a dose of 17.1 g/kg daily. On day 14, the colon length was measured, the colorectal histopathological damage score was assessed, and protein levels of interleukin (IL)-1β, IL-8 and tumor necrosis factor-alpha (TNF-α) in colon supernatants were measured by enzyme-linked immunosorbent assay. mRNA expression of IL-1β, IL-8, TNF-α and nuclear factor-kappa B (NF-κB) was detected by real-time quantitative polymerase chain reaction. Western blotting was used to detect the protein expression of NF-κB and inhibitor of kappa B.RESULTSAcute inflammation occurred in the mice administered DSS, including the symptoms of losing body weight, loose feces/watery diarrhea and presence of fecal blood; all these symptoms worsened at 7 d. The colons of mice treated with DSS were assessed by histological examination, and the results confirmed that acute inflammation had occurred, as evidenced by loss of colonic mucosa and chronic inflammatory cell infiltration, and these features extended into the deeper layer of the colon walls. The expression levels of IL-1β, IL-8 and TNF-α in the DSS group were higher than those in the control group (P < 0.05), and the expression levels of IL-1β, IL-8 and TNF-α in the JPQCD and 5-ASA groups were lower than those in the DSS group after treating with JPQCD and 5-ASA. Comparing with the DSS group, the mRNA level of IL-1β, IL-8, TNF-α and NF-κB was significantly reduced by 5-ASA and JPQCD. The difference between JPQCD and 5-ASA groups was not statistically significant (P > 0.05). Comparing with the DSS group, due to using JPQCD and 5-ASA, significant suppression of activation in DSS-induced NF-κB and increased phosphorylation of IκB in mice with experimental colitis occurred (P < 0.05). The difference between the JPQCD group and the 5-ASA group was not statistically significant (P > 0.05).CONCLUSIONActivation of the NF-κB signaling pathway is inhibited by JPQCD, which shows the potential mechanism by which JPQCD treats UC.

Micro-Pulse Lidar Measurements of Aerosol Vertical Structure over the Loess Plateau

Knowledge of the vertical distribution of aerosols in the free troposphere is important for estimating their impact on climate. In this study, direct observations of the vertical distribution of aerosols in the free troposphere are made using surface Micro-Pulse Lidar (MPL) measurements. The MPL measurements were made at the Loess Plateau (35.95°N, 104.1°E), which is near the major dust source regions of the Taklimakan and Gobi deserts. The vertical distribution of the MPL backscattering suggested that nondust aerosols floated from ground level to an altitude of approximately 9 km around the source regions. Early morning hours are characterized by a shallow aerosol layer of a few hundred meters thick. As the day progresses, strong convective eddies transport the aero- sols vertically to more than 1500 m.

Experimental investigation on CO_2-light crude oil interfacial and swelling behavior

A systematic series of experiments are designed and performed including inteffacial tension （IFT） measurements concomitant with Bond （BN, the ratio of gravity forces to capillary forces） and swelling/extraction measurements. Dynamic IFT, BN and swelling/extraction are measured as a function of pressure at temperatures of 30, 50 and 80 ℃. In addition, in the light of measured IFT the minimum miscibility pressure （MMP） of CO2 and light crude oil is determined based on a method called vanishing inteffacial tension （VIT）. The obtained results interestingly revealed that equilibrium IFT decreases linearly with pressure in two distinct pressure intervals while equilibrium BN shows an increasing trend as a function of pressure for all of the studied cases while no obvious trend is observed for swell- ing of crude oil and extraction of light-components regarding time, temperature and pressure.

Evolution of Quantum State for Mesoscopic Circuits with Dissipation

Based on the maximum entropy principle, we present a density matrix of mesoscopic RLC circuit to make it possible to analyze the connection of the initial condition with temperature. Our results show that the quantum state evolution is closely related to the initial condition, and that the system evolves to generalized coherent state if it is in ground state initially, and evolves to squeezed state if it is in excited state initially.

Uncertainties in Quantitatively Estimating the Atmospheric Heat Source over the Tibetan Plateau

As a huge,intense,and elevated atmospheric heat source(AHS) approaching the mid-troposphere in spring and summer,the Tibetan Plateau(TP) thermal forcing is perceived as an important factor contributing to the formation and variation of the Asian summer monsoon.Despite numerous studies devoted to determine the strength and change of the thermal forcing of the TP on the basis of various data sources and methods,uncertainties remain in quantitative estimation of the AHS and will persist for the following reasons:(1) Routine meteorological stations cover only limited regions and show remarkable spatial inhomogeneity with most distributed in the central and eastern plateau.Moreover,all of these stations are situated at an altitude below 5000 m.Thus,the large area above that elevation is not included in the data.(2) Direct observations on heat fluxes do not exist at most stations,and the sensible heat flux(SHF) is calculated by the bulk formula,in which the drag coefficient for heat is often treated as an empirical constant without considering atmospheric stability and thermal roughness length.(3) Radiation flux derived by satellite remote sensing shows a large discrepancy in the algorithm in data inversion and complex terrain.(4) In reanalysis data,besides the rare observational records employed for data assimilation,model bias in physical processes induces visible errors in producing the diabatic heating fields.

A unique case of collagenous colitis presenting as protein-losing enteropathy successfully treated with prednisolone

A 76-year-old woman with a 5-mo history of recurrent diarrhea and generalized edema was admitted to our hospital. Colonoscopy revealed edematous mucosa,and histopathological examination was compatible with collagenous colitis. Protein leakage from the colon,particularly in the ascending portion,was identified on 99mTc-human serum albumin scintigraphy. Collagenous colitis associated with protein-losing enteropathy (PLE) without small bowel disease was diagnosed. Prednisolone treatment ameliorated diarrhea and hypoproteinemia. Collagenous colitis should be included in the differential diagnosis of chronic diarrhea with hypoproteinemia for appropriate management.

Large Scale VLSI Module Placement Using LFF Heuristics by Stages

We present a deterministic algorithm for large-scale VLSI module placement. Following the less flexibility first （LFF） principle,we simulate a manual packing process in which the concept of placement by stages is introduced to reduce the overall evaluation complexity. The complexity of the proposed algorithm is （N1 ＋ N2 ） × O（ n^2 ） ＋ N3× O（n^4lgn） ,where N1, N2 ,and N3 denote the number of modules in each stage, N1 ＋ N2 ＋ N3 = n, and N3〈〈 n. This complexity is much less than the original time complexity of O（n^5lgn）. Experimental results indicate that this approach is quite promising.

Postembryonic Development of Electrophysiological Characteristic of Primordial Hippocampus in Bufo bufo gargarizans

[Objective] The aim was to probe into developing changes of spontaneous electrical activities of primordial hippocampus in Bufo bufo gargarizans in postembryonic phase. [Method] Microelectrode technique was used to record extracellularly spontaneous electrical activities of neurons in primordial hippocampus of B.bufo gargarizans in postembryonic phase. [Result] Single, consecutive single, burst, consecutive burst and anomalous spontaneous firing were recorded in primordial hippocampus, in which four kinds of spontaneous firings were recorded in forepart of postembryonic development except the anomalous spontaneous firing, and the burst spontaneous firing and consecutive burst spontaneous firing were predominant. The five kinds of spontaneous firings mentioned were recorded in anaphase of postembryonic development and the single and burst spontaneous firing were predominant.Following with the development of primordial hippocampus, the amplitudes of action potential of single firing and consecutive firing enhanced gradually, and it reaches the maximum in the metamorphosis phase; the differences of the frequencies of consecutive single firing and consecutive burst firing were not significant. [Conclusion] Following with the development of primordial hippocampus, the neuronal electrical activities showed diversification, the developmental degree of the primordial hippocampus in the metamorphosis phase was close to the subadult and adult.

Reevaluation of cortical developmental patterns in Euplotes(s.l.), including a morphogenetic redescription of E.charon (Protozoa,Ciliophora,Euplotida)

We documented the pattern of cell development in Euplotes charon. The ontogenesis of this species was similar to many of its congeners, except for the formation of the caudal cirri. In E. Charon, a caudal cirrus is formed posterior to each of the rightmost two or three dorsal kinety anlage in the proter, and the second rightmost dorsal kinety in the opisthe. In addition, two caudal cirri are formed posterior to the rightmost dorsal kinety in the opisthe. This pattern of development represents a completely new type. Based on our evaluation, and in comparison with previous studies, we also conclude that the pattern of cell development is variable among species in the Euplotes genera. The variation is particularly evident during the formation of frontoventral and caudal cirri. Based on the segmentation pattern of frontal-midventral transverse cirral anlagen, cirri reduction, and migration of frontoventral cirri, we identified five types: the affinis-type, the eurystomus-type, the charon-type, the raikovi-type and orientalis-type. Euplotes (s. l.) can also be divided into three types based on the formation of caudal cirri: focardii-type, vannus-type and charon-type. Indeed, we conclude that the number (one or two) of marginal cirri should be given as much consideration as the genetic separation. Given this, we reassessed the validity of using genetic separation to classify the group. Generally, the morphogenetic data disagreed with the molecular data (SSrRNA gene sequences). Given these discrepancies, it is too early to draw conclusions on the systematic arrangement of this species-rich taxon.