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Smallest Number (smallest + number)
Selected AbstractsChallenging Wallacean and Linnean shortfalls: knowledge gradients and conservation planning in a biodiversity hotspotDIVERSITY AND DISTRIBUTIONS, Issue 5 2006Luis Mauricio Bini ABSTRACT Knowledge about biodiversity remains inadequate because most species living on Earth were still not formally described (the Linnean shortfall) and because geographical distributions of most species are poorly understood and usually contain many gaps (the Wallacean shortfall). In this paper, we developed models to infer the size and placement of geographical ranges of hypothetical non-described species, based on the range size frequency distribution of anurans recently described in the Cerrado Biome, on the level of knowledge (number of inventories) and on surrogates for habitat suitability. The rationale for these models is as follow: (1) the range size frequency distribution of these species should be similar to the range-restricted species, which have been most recently described in the Cerrado Biome; (2) the probability of new discoveries will increase in areas with low biodiversity knowledge, mainly in suitable areas, and (3) assuming range continuity, new species should occupy adjacent cells only if the level of knowledge is low enough to allow the existence of undiscovered species. We ran a model based on the number of inventories only, and two models combining effects of number of inventories and two different estimates of habitat suitability, for a total of 100 replicates each. Finally, we performed a complementary analysis using simulated annealing to solve the set-covering problem for each simulation (i.e. finding the smallest number of cells so that all species are represented at least once), using extents of occurrence of 160 species (131 real anuran species plus 29 new simulated species). The revised reserve system that included information about unknown or poorly sampled taxa significantly shifted northwards, when compared to a system based on currently known species. This main result can be explained by the paucity of biodiversity data in this part of the biome, associated with its relatively high habitat suitability. As a precautionary measure, weighted by the inferred distribution data, the prioritization of a system of reserves in the north part of the biome appears to be defensible. [source] Partial uniqueness in CANDECOMP/PARAFACJOURNAL OF CHEMOMETRICS, Issue 1 2004Jos M. F. ten Berge Abstract A key property of CANDECOMP/PARAFAC is the essential uniqueness it displays under certain conditions. It has been known for a long time that, when these conditions are not met, partial uniqueness may remain. Whereas considerable progress has been made in the study of conditions for uniqueness, the study of partial uniqueness has lagged behind. The only well known cases are those of overfactoring, when more components are extracted than are required for perfect fit, and those cases where the data do not have enough system variation, resulting in proportional components for one or more modes. The present paper deals with partial uniqueness in cases where the smallest number of components is extracted that yield perfect fit. For the case of K×K×2 arrays of rank K, randomly sampled from a continuous distribution, it is shown that partial uniqueness, with some components unique and others differing between solutions, arises with probability zero. Also, a closed-form CANDECOMP/PARAFAC solution is derived for 5×3×3 arrays when these happen to have rank 5. In such cases, any two different solutions share four of the five components. This phenomenon will be traced back to a sixth degree polynomial having six real roots, any five of which can be picked to construct a solution. Copyright © 2004 John Wiley & Sons, Ltd. [source] Liver organ allocation for hepatocellular carcinoma: Are we sure?LIVER TRANSPLANTATION, Issue 7 2003J. Wallis Marsh Of patients with hepatocellular carcinoma (HCC), 70% to 90% present with cirrhosis. Accordingly, liver transplantation ,LT), not liver resection, currently remains the only possibility of cure for these patients. Because there is a severe shortage of liver organ donors, not all patients in need can be offered LT. Therefore, transplant listing criteria simultaneously must determine the greatest number of suitable candidates for transplantation while rejecting the smallest number of those who could benefit from LT. The objective of this study was to determine the outcome of patients with HCC who are denied LT by current listing criteria. Of patients who are being denied liver transplantation by the current United Network for Organ Sharing listing criteria (but who were transplanted before the current guidelines took effect(, 27% to 49% were cured by this procedure. The listing criteria for LT in the presence of HCC should reflect the minimum acceptable )not maximum acceptable) recurrence-free survival rate and must reflect a consensus of the transplant community. [source] Water-Soluble Polymeric Thioxanthone Photoinitiator Containing Glucamine as CoinitiatorMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 15 2008Xuesong Jiang Abstract A novel kind of water-soluble polymeric photoinitiator was synthesized by introducing thioxanthone moieties and glucamine into the polymeric chain, as well as low-molecular weight model compounds. The photochemical and photophysical properties of these photoinitiators were studied. PTX-GA possesses a similar UV-vis absorption, weaker fluorescence emission and a shorter lifetime of the TX triplet state (,) as compared to TX-MGA and TX-PMAC/MDEA. ESR showed that in TX-PMAC/MDEA the smallest number of radicals is generated. Photopolymerization of arylamide and methylene bisacryamide initiated by these photoinitiators shows that PTX-GA is more effective than TX-MGA and TX-PMAC/MDEA. [source] Multigraph augmentation under biconnectivity and general edge-connectivity requirements ,NETWORKS: AN INTERNATIONAL JOURNAL, Issue 3 2001Toshimasa Ishii Abstract Given an undirected multigraph G = (V, E) and a requirement function r,: () , Z+ (where () is the set of all pairs of vertices and Z+ is the set of nonnegative integers), we consider the problem of augmenting G by the smallest number of new edges so that the local edge-connectivity and vertex-connectivity between every pair x, y , V become at least r,(x, y) and two, respectively. In this paper, we show that the problem can be solved in O(n3(m + n) log(n2/(m + n))) time, where n and m are the numbers of vertices and pairs of adjacent vertices in G, respectively. This time complexity can be improved to O((nm + n2 log n) log n), in the case of the uniform requirement r,(x, y)= ,, for all x, y , V. Furthermore, for the general r,, we show that the augmentation problem that preserves the simplicity of the resulting graph can be solved in polynomial time for any fixed ,,* = max{r,(x, y) | x, y , V}. © 2001 John Wiley & Sons, Inc. [source] Principles in quality assurance.QUALITY ASSURANCE JOURNAL, Issue 1 2003Part 2. Abstract In order to achieve and sustain effective compliance with the quality regulations, an understanding of the rationale for compliance must be developed throughout an organization. Developing such an organizational understanding is difficult to attain through training based solely on the text of the regulations or the company's Standard Operating Procedures (SOPs). These do have their place, but there is too much information, and the effects of training dissipate rapidly because personnel cannot effectively retain detailed information. In our organization, we undertook a process of simplification of the regulations, in an attempt to define the smallest number of basic quality principles that are embodied in Good Laboratory Practice (GLP) and associated regulations. The systematic application of these quality principles is a mechanism by which Quality Assurance (QA) can be clear and consistent in its monitoring and training activities. This process empowers all personnel to make correct compliance decisions without having to consult the detail of the regulations at every turn. The establishment and application of this concept at a bioanalytical contract research laboratory is described in this article. Copyright © 2003 John Wiley & Sons, Ltd. [source] Characteristics of Buck Semen with Regard to Ejaculate Numbers, Collection Intervals, Diluents and Preservation PeriodsREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2000M Shamsuddin Contents To determine the number of ejaculates which can be collected within a 20-min period after the smallest number of days of sexual rest, and a good diluent to preserve semen for routine AI, five mature Black Bengal bucks were used in three experiments. In experiment 1, semen from the bucks were collected by using artificial vagina at homosexual mounts as many times as possible during 20 min. The ejaculate numbers 1, 3 and 4 (or 5 when the buck could produce it) were examined for important semen characteristics. The mean ejaculate volume, density, mass activity, sperm motility, sperm concentrations, total spermatozoa/ejaculate, proportion of spermatozoa with normal acrosome, midpiece and tail, and the proportion with normal head morphology varied between 267 and 342 µl, 4.1,4.5 (1,5 scale), 4.1,4.2 (1,5 scale), 77,79%, 4187 × 106,5064 × 106/ml, 1140 × 106,1746 × 106, 91,94% and 99%, respectively, depending on the collection number of the ejaculate. The difference between the ejaculates was significant only with respect to volume (p < 0.05). In experiment 2, semen was collected from the bucks successively during 20 min after 1, 2, 3 and 4 day intervals, and the first ejaculates were evaluated for the above-mentioned semen characteristics. Semen collected after 2 or more day intervals had significantly higher volume, sperm concentration and total spermatozoa/ejaculate (p < 0.05). In experiment 3, pools of two to three ejaculates were diluted (1 : 5; semen : diluent) in splits with glucose-citrate-egg yolk (GCEY), Tris-fructose-egg yolk (TFEY) or skim milk (SM) and preserved at +4 to +7°C. Before chilling or after 0 (15 min chilling), 1, 2, 3 and 4 days of preservation, semen was evaluated for motility and proportion of normal spermatozoa with respect to acrosome, midpiece and tail. In data pooled across the bucks, the sperm motility was better in GCEY and TFEY than in SM, and the proportion of normal spermatozoa was higher in SM than in the others (p < 0.05). However, the differences in proportion of normal spermatozoa between diluents were not significant when the data were analysed separately within preservation periods. The sperm motility consistently dropped after 1 day of preservation (p < 0.01); the motility remained 50% or more up to 4 days in TFEY, 3 days in GCEY and only 2 days in SM. The proportion of spermatozoa with normal acrosome, midpiece and tail, which was generally quite high ( 90%), decreased after 3 days of preservation (p < 0.01). We conclude that Black Bengal bucks can be collected three times during 20 min, every 3 days, and that buck semen holds good motility and proportion of normal spermatozoa up to 3 days in GCEY or TFEY at 4 to 7°C. [source] Adrenergic and Cholinergic Innervation of the Mammary Gland in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2002A. FRANKE-RADOWIECKA Adrenergic and acetylcholinesterase-positive (AChE-positive) innervation of the mammary gland in the sexually immature and mature pigs was studied using histochemical methods. Upon examining the adrenergic and cholinergic innervation, the adrenergic innervation was found to be much more developed. The majority of both sub-populations of the nerve fibres studied was localized in the subcutaneous tissue of the mammary gland. Adrenergic and AChE-positive nerve fibres also supplied structures of the nipple (subcutaneous tissue, blood vessels, smooth muscles fibres) and glandular tissue (blood vessels, lactiferous ducts). The glandular tissue contained the smallest number of adrenergic and AChE-positive nerve fibres. No distinct differences were observed in the adrenergic and AChE-positive innervation of the porcine mammary gland between the juvenile and non-pregnant adult animals. [source] Structure of a mutant T = 1 capsid of Sesbania mosaic virus: role of water molecules in capsid architecture and integrityACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2005V. Sangita Deletion of the N-terminal 31 amino acids from the coat protein (CP) of Sesbania mosaic virus (SeMV) results in the formation of T = 1 capsids. The X-ray crystal structure of CP-N,31 mutant capsids reveals that the CP adopts a conformation similar to those of other T = 1 mutants. The 40 N-terminal residues are disordered in CP-N,31. The intersubunit hydrogen bonds closely resemble those of the native capsid. The role of water molecules in the SeMV structure has been analyzed for the first time using the present structure. As many as 139 of the 173 waters per subunit make direct contacts with the protein atoms. The water molecules form a robust scaffold around the capsid, stabilize the loops and provide integrity to the subunit. These waters constitute a network connecting diametrically opposite ends of the subunit. Such waters might act as nodes for conveying signals for assembly or disassembly across a large conformational space. Many water-mediated interactions are observed at various interfaces. The twofold interface, which has the smallest number of protein,protein contacts, is primarily held by water-mediated interactions. The present structure illuminates the role of water molecules in the structure and stability of the capsid and points out their possible significance in assembly. 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