Analysis of bulked segregants to identify molecular markers linked with cocoon weight and cocoon shell weight in the silkworm Bombyx mori L

Two silkworm strains viz, B20 A (high cocoon shell ratio) and C.Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygosis. Both bulked segregant analysis(BSA) and near isogenic lines (NIL) studies were done to identify the RFLP markers closely linked to cocoon shell parameters. Three hundred and fifty-two random clones were identified as the low copy number sequence and used for identification of Restriction Fragment Length Polymorphic (RFLP) marker linked to cocoon weight and cocoon shell character. In the bulk segregant analysis, DNA from the parents (B20 A, C.Nichi), F1 and F2 progeny of high shell ratio (HSR) and low shell ratio (LSR) were screened for hybridization with the random clones. Polymorphic banding pattern achieved through southern hybridization with different probes indicated the probable correlation of polymorphism with high and low cocoon shell character which are possible landmarks in identifying the putative marker(s) for the cocoon shell character. Out of the 100 probes tried with parents, F1, F2 and their bulks, 10 probes were found to be closely linked to cocoon shell characters.     

Accumulation of 1-deoxynojirimycin in silkworm, <Emphasis Type="Italic">Bombyx mori</Emphasis> L.

1-deoxynojirimycin (1-DNJ) contents in the silkworm,Bombyx mori,at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silkworm larvae change significantly with their developmental stages. The male larvae showed higher accumulation efficiency of 1-DNJ than the females and also a significant variation was observed among the silkworm strains. The present results show that tissue distribution of 1-DNJ was significantl...     

On some projectively flat polynomial （α,β）-metrics

In this paper, we consider some polynomial (α,β)-metrics, and discuss the sufficient and necessary conditions for a Finsler metric in the form F=α a1β a2β2/α a4β4/α3 to be projectively flat, where ai (i=1,2,4) are constants with a1≠0, α is a Riemannian metric and β is a 1-form. By analyzing the geodesic coefficients and the divisibility of certain polynomials, we obtain that there are only five projectively flat cases for metrics of this type. This gives a classification for such kind of Finsler metrics.     

A note on the Marcinkiewicz integral operators on Fp^a,q

In this paper, we shall prove that the Marcinkiewicz integral operator #n, when its kernel Ω satisfies the L^1-Dini condition, is bounded on the Triehel-Lizorkin spaces. It is well known that the Triehel-Lizorkin spaces are generalizations of many familiar spaces such as the Lehesgue spaces and the Soholev spaces. Therefore, our result extends many known theorems on the Marcinkiewicz integral operator. Our method is to regard the Marcinkiewicz integral operator as a vector valued singular integral. We also use another characterization of the Triehel-Lizorkin space which makes our approach more clear.     

两个Ramsey数R(m,n,l)和R(m,n,l,s)的含参数的上界

Ｉｎ 1935 ,Ｐ .Ｅｒｄ¨ｏｓａｎｄＧＳｚｅｋｅｒｅｓｏｂｔａｉｎｅｄｔｈｅｃｌａｓｓｉｃａｌｉｎｅｑｕａｌｉｔｙＲ (ｍ ,ｎ)≤Ｒ (ｍ - 1,ｎ) Ｒ(ｍ ,ｎ - 1) .　Ｉｎ 196 8,Ｋ .ＷａｌｋｅｒｐｒｏｖｅｄｔｈａｔＲ(ｎ ,ｎ)≤ 4Ｒ(ｎ- 2 ,ｎ) 2 .　Ｉｎ 1998,ＨｕａｎｇＹ .Ｒ .ａｎｄＺｈａｎｇＫ .Ｍ .[1,2 ] ｐｒｏｖｅｄｔｈａｔＲ(ｍ ,ｎ)≤ 12 (β 3γ 5 ) 　　12 γ(4α 2 β - 3γ 6 ) (β 1) 2　Ｉｎｔｈｉｓｐａｐｅｒ ,ｗｅｏｂｔａｉｎｓｏｍｅｎｅｗｕｐｐｅｒｂｏｕｎｄｓｆｏｒＲ(ｍ ,ｎ ,ｌ)ａｎｄＲ(ｍ …     

Targeting of human aFGF gene into silkworm,<Emphasis Type="Italic">Bombyx mori</Emphasis> L. through homologous recombination

The long-arm and short-arm genes of fibroin light chain (L-chain) of silkworm,Bombyx Mori L., and the gene of human acidic fibroblast growth factor were cloned respectively and subsequently inserted into a transfer vector pVL 1392 used as a tool to target the L-chain region of the silkworm genome. Genomic DNA from their offsprings was extracted and the expected targeting was detected using polymerase chain reaction and DNA sequencing, as well as protein analysis. The results showed that positive events occurred and that the FGF gene was integrated into the L-chain locus through homologous recombination. Project supported by the Scientific Research Foundation for Returned Overseas Chinese Scholars, Education Ministry of China and the Natural Science Foundation of Zhejiang Province (No. 301306), China     

<Emphasis Type="Italic">Negativity</Emphasis> and the <Emphasis Type="Italic">new</Emphasis> in John Dewey’s theory of learning and democracy

Zusammenfassung Negativit?t und das Neue in John Deweys Theorie vom Lernen und der Demokratie — Für einen erneuten Blick auf Lernkulturen Die Rolle des Neuen in Lernprozessen bezieht sich auf die grundlegende Frage, wie Lernen überhaupt m?glich ist und wo es beginnt. In diesem Beitrag wird zun?chst John Deweys Lernkonzeption als Basis für die Analyse entwickelt. Dann wird die Beziehung zwischen Negativit?t und dem Neuen erarbeitet. Beim übergang vom Alten zum Neuen und vom Gewussten zum Ungewussten entstehen Verwirrungen und Schwierigkeiten, die in diesem Papier als Negativit?t im Lernprozess untersucht werden. Au?erdem vermittelt der Beitrag Einsichten in praktische p?dagogische Probleme, etwa bezüglich der Frage, wie Lehrer und andere Erzieher Lernprozesse f?rdern und wie Lernkulturen als besondere Lernumwelten Lehr-Lern-Prozesse unterstützen k?nnen.

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Negativity and the new in John Dewey’s theory of learning and democracy Toward a renewed look at learning cultures

Summary The role of the New in learning processes relates to basic questions of how learning is possible, and where learning begins. Using John Dewey’s concept of learning as the basis for analysis, this inquiry looks into the relation between Negativity and the New and seeks to uncover the negativity in learning processes associated with the perplexities and difficulties which arise in the transitions from Old to New and Known to Unknown. Furthermore, it offers insight into practical pedagogical issues, such as how teachers and educators can support learning processes and how learning cultures, as particular environments for learning, can assist processes of teaching and learning.

     

Euclid and ‘<Emphasis Type="Italic">The Elements</Emphasis>’

When a crime is committed and the culprit responsible for the crime is nabbed, the job of the investigators is not over. To convince the judge, they have to prove beyond doubt that it was the accused who committed the crime. Likewise, mathematical statements require proofs for their veracity to be established. Further, to make these statements precise we need to have a set of proper definitions. It was Euclid, who more than two thousand years ago, started this tradition when he bequeathed to the world his book entitled The Elements. This tradition has continued since then. Definitions, proofs besides axioms have become an inalienable part of mathematical lore. We owe all this to Euclid, one of the greatest pioneers of rigour and reasoning. In this article we discuss the work of Euclid.     

<Emphasis Type="Italic">Mathematical sophistication</Emphasis> among preservice elementary teachers

This study explores the ways in which eleven preservice elementary teachers used a web-based teacher resource to apply a mathematical definition, to correct a procedural error in arithmetic, and to make sense of a story requiring the multiplication of fractions. In our analysis we propose a framework to compare the behaviors and values expressed by our participants with the values and norms of the mathematical community. This analysis suggests that many preservice elementary teachers are profoundly mathematically unsophisticated. In other words, they displayed a set of values and avenues for doing mathematics so different from that of the mathematical community, and so impoverished, that they found it difficult to create fundamental mathematical understandings.     

Software Development for Digital Control of WDW Series Testing Machine and Measurement of KIC

Software has been developed for digital control of WDW series testing machine and the measurement of fracture toughness by modularized design. Development of the software makes use of multi-thread and serial communication techniques, which can accurately control the testing machine and measure the fracture toughness in real-time. Three-point bending specimens were used in the measurement. The software operates stably and reliably, expanding the function of WDW series testing machine.     

Nonlinear Riemann Problem for Nonlinear Elliptic Systems in Sobolev Space W1，p（ D ）

The nonlinear Riemann problems were converted into nonlinear singular integral equations and the existence of the solution for the problem was proved by means of contract principle.     

Lovastatin production by Aspergillus terreus in solid-state fermentation

Lovastatin production by Aspergillus terreus ATCC 20542 in solid-state fermentation (SSF) was studied. Various substrates were used to evaluate the ability of A. terreus to produce lovastatin. The results showed that either rice or wheat bran was suitable substrate for lovastatin production in SSF. The maximum yield of lovastatin (2.9 mg/g dry substrate) using rice as substrate was achieved after incubating for 11 d at the following optimized process parameters: 50%～60% initial moisture content,pH 5.5,incubation temperature 28 °C.     

5阶KdV方程的一类新多孤子解

Using bilinear transformation method,a new N-soliton solutions were obtained for the Sawada-Kotera equation.