不同高光谱特征参数区分马铃薯品种的优劣势分析

对马铃薯关键生育期的高光谱遥感图像进行特征提取和分析,提出了一种快速区分不同马铃薯品种的方法。以两个早熟和中熟马铃薯品种为研究对象,采集其块茎形成期、块茎膨大期和淀粉积累期的冠层反射光谱曲线,对实测反射光谱曲线进行Savitzky-Golay滤波平滑和一阶微分处理,以高光谱位置参数、振幅参数、面积参数、宽度参数和反射率参数为研究指标,根据21个高光谱特征参数的贡献率大小,评价了其区分不同马铃薯品种的优劣。结果表明：(1)同一类高光谱特征参数在不同生育期区分马铃薯品种的能力不同: 高光谱位置参数、宽度参数和反射率参数在块茎膨大期区分不同马铃薯品种的能力最强,淀粉积累期次之;高光谱振幅参数和面积参数在淀粉积累期的区分能力最强,块茎膨大期次之,五类高光谱特征参数在块茎形成期的区分能力均最差。(2)同一生育期5类高光谱特征参数区分马铃薯品种的能力也存在差异。在块茎形成期,五类高光谱特征参数的区分能力从强到弱依次为：反射率参数>振幅参数>面积参数>宽度参数>位置参数;在块茎膨大期和淀粉积累期,从强到弱依次为：面积参数>振幅参数>反射率参数>宽度参数>位置参数。综合能力从强到弱依次为：面积参数>振幅参数>反射率参数>宽度参数>位置参数。     

应用FTIR直接测定法鉴定大豆的品种

利用傅里叶变换红外光谱(FTIR)法测定了8个不同大豆品种的子叶及外表皮的红外光谱,对他们的红外光谱进行了分析,并对其吸收峰进行了归属。通过对各谱图的比较分析发现,不同的大豆品种的红外吸收峰形及峰强有所区别。结果表明： 不同的大豆品种的FTIR有明显的差别,特别是1 800～1 200 cm-1范围内有较大的差异,它反映的主要是蛋白质分子的酰胺Ⅰ带及酰胺Ⅱ带附近,这可能是源于基因的差异。因此FTIR法可用于不同大豆品种的鉴别。     

傅里叶自解卷积-红外光谱分析法应用于中药天麻的鉴别研究

采用水平衰减全反射-傅里叶变换红外光谱法(HATR-FTIR)对不同产地的野生及种植天麻与伪品芭蕉芋、芋及马铃薯进行了测定,并通过傅里叶自解卷积(FSD)进行了转换。在各种带宽因子及增强因子下对真伪品傅里叶自解卷积红外光谱的差异程度进行了分析研究,结果发现带宽因子在75.0～76.0,增强因子为3.2时,天麻与伪品的FSD-IR的差异程度最为明显。结果表明,尽管从FTIR中很难发现野生及种植天麻、无性繁殖及有性繁殖天麻之间的差异,但从FSD-IR中可以看出他们之间的差异。而天麻正品与伪品之间的FSD-IR差别也较大。因此该法可简便、快速、准确地识别不同的天麻及其伪品。     

Deformation Quantization of Algebraic Varieties

The paper is devoted to peculiarities of the deformation quantization in the algebro-geometric context. A direct application of the formality theorem to an algebraic Poisson manifold gives a canonical sheaf of categories deforming coherent sheaves. The global category is very degenerate in general. Thus, we introduce a new notion of a semiformal deformation, a replacement in algebraic geometry of an actual deformation (versus a formal one). Deformed algebras obtained by semiformal deformations are Noetherian and have polynomial growth. We propose constructions of semiformal quantizations of projective and affine algebraic Poisson manifolds satisfying certain natural geometric conditions. Projective symplectic manifolds (e.g. K3 surfaces and Abelian varieties) do not satisfy our conditions, but projective spaces with quadratic Poisson brackets and Poisson–Lie groups can be semiformally quantized.     

On a theorem of Tate

We study applications of divisibility properties of recurrence sequences to Tate’s theory of abelian varieties over finite fields.      

On <Emphasis Type="Italic">n</Emphasis> × <Emphasis Type="Italic">m</Emphasis>-valued Łukasiewicz-Moisil algebras

n×m-valued Łukasiewicz algebras with negation were introduced and investigated in [20, 22, 23]. These algebras constitute a non trivial generalization of n-valued Łukasiewicz-Moisil algebras and in what follows, we shall call them n×m-valued Łukasiewicz-Moisil algebras (or LM _n×m -algebras). In this paper, the study of this new class of algebras is continued. More precisely, a topological duality for these algebras is described and a characterization of LM _n×m -congruences in terms of special subsets of the associated space is shown. Besides, it is determined which of these subsets correspond to principal congruences. In addition, it is proved that the variety of LM _n×m -algebras is a discriminator variety and as a consequence, certain properties of the congruences are obtained. Finally, the number of congruences of a finite LM _n×m -algebra is computed.      

Cohomology of the Orlik–Solomon Algebras and Local Systems

The paper provides a combinatorial method to decide when the space of local systems with nonvanishing first cohomology on the complement to an arrangement of lines in a complex projective plane has as an irreducible component a subgroup of positive dimension. Partial classification of arrangements having such a component of positive dimension and a comparison theorem for cohomology of Orlik–Solomon algebra and cohomology of local systems are given. The methods are based on Vinberg–Kac classification of generalized Cartan matrices and study of pencils of algebraic curves defined by mentioned positive dimensional components.     

Characterization of standard embeddings between complex Grassmannians by means of varieties of minimal rational tangents

In 1993,Tsal proved that a proper holomorphic mapping f:Ω→Ω' from an irreducible bounded symmetric domainΩof rank≥2 into a bounded symmetric domainΩ' is necessarily totally geodesic provided that r':=rank(Ω')≤rank(Ω):= r,proving a conjecture of the author's motivated by Hermitian metric rigidity.As a first step in the proof,Tsai showed that df preserves almost everywhere the set of tangent vectors of rank 1.Identifying bounded symmetric domains as open subsets of their compact duals by means of the Borel embedding,this means that the germ of f at a general point preserves the varieties of minimal rational tangents(VMRTs). In another completely different direction Hwang-Mok established with very few exceptions the Cartan- Fubini extension priniciple for germs of local biholomorphisms between Fano manifolds of Picard num- ber 1,showing that the germ of map extends to a global biholomorphism provided that it preserves VMRTs.We propose to isolate the problem of characterization of special holomorphic embeddings between Fano manifolds of Picard number 1,especially in the case of classical manifolds such as ratio- nal homogeneous spaces of Picard number 1,by a non-equidimensional analogue of the Cartan-Fubini extension principle.As an illustration we show along this line that standard embeddings between com- plex Grassmann manifolds of rank≤2 can be characterized by the VMRT-preserving property and a non-degeneracy condition,giving a new proof of a result of Neretin's which on the one hand paves the way for far-reaching generalizations to the context of rational homogeneous spaces and more generally Fano manifolds of Picard number 1,on the other hand should be applicable to the study of proper holomorphic mappings between bounded domains carrying some form of geometric structures.     

Determination of phenolic compounds in modern and old varieties of durum wheat using liquid chromatography coupled with time-of-flight mass spectrometry

An evaluation of the grain functional components of Italian durum wheat cultivars was conducted. The raw material was obtained from the field trial performed in 2006–2007 at the Experimental Farm of the University of Bologna, (Bologna, Italy). The aim of this study was to define the phytochemical profile of ten varieties, comprised of old and modern durum wheat genotypes, including quantitative and qualitative phenolic and flavonoid content (free and bound forms). The results showed that mean values of total phenolic compound and total flavonoid content in old wheat varieties (878.2 ± 19.0 μmol gallic acid equivalent/100 g of grain and 122.6 ± 25.4 μmol catechin equivalent/100 g of grain, respectively) did not differ significantly from those detected in modern genotypes (865.9 ± 128.9 μmol gallic acid equivalent/100 g and 123.5 ± 20.6 μmol catechin equivalent/100 g, respectively). However, the HPLC–ESI-TOF-MS analysis highlighted remarkable differences between modern and old cultivars. The interpretation of the mass spectra allowed the identification of 70 phenolic compounds, including coumarins, phenolic acids, anthocyanins, flavones, isoflavones, proanthocyanidins, stilbenes and lignans. The free extracts of ancient wheat varieties showed the presence of a mean number of phenolic compounds and isomer forms (8.7 ± 2.5 and 7.7 ± 4.7 respectively) significantly higher than in modern genotypes (4.4 ± 2.9 and 2.0 ± 2.4, respectively). A similar trend was observed also for the bound phenolic fraction. Moreover, the phytochemical profiles showed the presence of unique phenolic compounds in both free and bound fractions of some of the investigated wheat genotypes. Results highlighted that investigated old wheat cultivars may offer unique nutraceutical values for their peculiar contents in bioactive phytochemicals, suggesting their uses into a wide range of regular and specialty products naturally enriched with health-promoting compounds.     

Commuting polarities and maximal partial ovoids of H(4,q2)

In PG(4,q²), q odd, let Q(4,q²) be a non‐singular quadric commuting with a non‐singular Hermitian variety H(4,q²). Then these varieties intersect in the set of points covered by the extended generators of a non‐singular quadric Q₀ in a Baer subgeometry Σ₀ of PG(4,q²). It is proved that any maximal partial ovoid of H(4,q²) intersecting Q₀ in an ovoid has size at least 2(q²+1). Further, given an ovoid O of Q₀, we construct maximal partial ovoids of H(4,q²) of size q³+1 whose set of points lies on the hyperbolic lines 〈P,X〉 where P is a fixed point of O and X varies in O\{P}. © 2009 Wiley Periodicals, Inc. J Combin Designs 17: 307–313, 2009