bluuebunny/crossref_metadata_2025_split huggingface dataset:
Irreversible Investment, Financing, and Bankruptcy Decisions in an Oligopoly
Authors: Jou Jyh-bang , Lee Tan 
Published: April 2009

AbstractThis paper examines a firm's debt level, investment timing, and investment scale choices in a continuous-time model where the output price of a good that the firm produces depends on a stochastic demand-shift variable and the total industry supply of the good. Using the simple symmetric Cournot-Nash equilibrium assumption that all firms are identical and therefore follow the same financing and investment strategies, we show that competition decreases the output price and hence encourages a firm to wait for a higher demand level before it is profitable to invest. We also demonstrate how uncertainty, bankruptcy costs, and corporate taxation affect the firm's financing and investment decisions.
The method of successive oscillatory fields
Authors: Ramsey Norman F. 
Published: April 2009

In 1949 I was looking for a way to measure nuclear magnetic moments by the molecular-beam resonance method, but to do it more accurately than was possible with the arrangement developed by I. I. Rabi and his colleagues at Columbia University. The method I found was that of separated oscillatory fields, in which the single oscillating magnetic field in the center of a Rabi device is replaced by two oscillating fields at the entrance and exit, respectively, of the space in which the nuclear magnetic moments are to be investigated. During the 1950's this method became extensively used in the original form. In the same period more general applications of the method arose, and the principal extensions included:
▸ Use of relative phase shifts between the two oscillatory fields
▸ Extension generally to other resonance and spectroscopic devices, such as masers, which depend on either absorption or stimulated emission
▸ Separation of oscillatory fields in time instead of space
▸ Use of more than two successive oscillatory fields
▸ General variation of amplitudes and phases of the successive applied oscillatory fields.
A correction
Authors: Courtoy C. 
Published: April 2009

I would like to call your attention to two small historical mistakes in your September issue.
On page 45: It was not Marcel de Broglie, but Maurice de Broglie, who attended the Solvay Congress.
On page 121: Georges Lemaître did not go to Louvain to study humanities. The Collège du Sacré-Coeur is in Charleroi, where Lemaître was born.
Errata
Authors: Gorter C. J. 
Published: April 2009

Thank you for the way my talk on “Bad Luck” was presented in the January issue. Unfortunately I myself made a few errors in the references, and since those are of some importance in a paper of somewhat historical nature, I hope you will publish a correction:
On page 77, column 1, line 7, read “the expected effect4a.”
On page 77, column 1, line 14, read “sunlight4b.”
Change the references to read as follows:
4a. C. J. Gorter, Leiden Comm. 247a, Physica 3, 995 (1936).
4b. C. J. Gorter, Physica 1, 199 (1934).
5. C. J. Gorter, Arch. Teyler 7, 378 (1933); C. J. Gorter, H. B. G. Casimir, Physica 1, 306 (1934); Phys. Z. 35, 963 (1934).
6. A. D. Fokker, C. J. Gorter, Z. Phys. 77, 166 (1932).
Systemic NK4 gene therapy inhibits tumor growth and metastasis of melanoma and lung carcinoma in syngeneic mouse tumor models
Authors: Kishi Yuko , Kuba Keiji , Nakamura Takahiro , Wen Jinhua , Suzuki Yoshinori , Mizuno Shinya , Nukiwa Toshihiro , Matsumoto Kunio , Nakamura Toshikazu 
Published: April 2009

Hepatocyte growth factor (HGF) promotes malignant development of cancer cells by enhancing invasion and metastasis. NK4, a competitive antagonist for HGF, is a bifunctional molecule that acts as a HGF antagonist and angiogenesis inhibitor. Although successful tumor inhibition by NK4 gene expression in tumor models has been demonstrated, the effects of systemic NK4 gene introduction are yet to be addressed. Here we show that systemic administration of a replication‐defective adenovirus expressing NK4 (Ad.NK4) inhibits tumor growth and lung metastasis of B16F10 melanoma and Lewis lung carcinoma in syngeneic mice. Single tail‐vein injection of Ad.NK4 achieved therapeutic levels of NK4 in the circulation and in multiple organs. Despite NK4 expression that was highest in the liver, toxicity in the liver was minimal. Ad.NK4‐mediated growth inhibition was associated with decreased blood vessel density and increased apoptosis in tumor tissues, which suggests that NK4 suppressed tumor growth as an angiogenesis inhibitor. Metastasis of B16F10 melanoma and Lewis lung carcinoma cells to the lung was potently inhibited by systemic Ad.NK4‐administration. Our results demonstrated that the adenovirus‐mediated induction of high levels of circulating NK4 significantly inhibited in vivo tumor growth and distant metastasis without obvious side effects. NK4 gene therapy is thus a safe and promising strategy for the treatment of cancer patients, and further validation in clinical trials is needed. (Cancer Sci 2009; 100: 1351–1358)
Evaluation of diquat against an acute experimental infection of Flavobacterium columnare in channel catfish, Ictalurus punctatus (Rafinesque)
Authors: Darwish A M , Mitchell A J 
Published: April 2009

AbstractA trial was performed to evaluate the efficacy of diquat (6,7‐dihydrodipyrido[1,2‐a:2′,1′‐c]pyrazinediium dibromide) against an acute experimental infection of Flavobacterium columnare in channel catfish, Ictalurus punctatus. Diquat is an Environmental Protection Agency‐approved herbicide and has the potential to be legally and practically used against columnaris. Channel catfish were challenged, by cutaneous abrasion, and waterborne exposure to F. columnare and treated once at 22‐h post‐challenge with 2.5, 5.0, 10.0 and 15 mg L−1 of diquat active ingredient for 6 h. At the conclusion of the trial, 21‐day post‐challenge, diquat at 5.0, 10.0 and 15 mg L−1 significantly (P < 0.05) reduced the mortality of infected fish from 95% in the challenged non‐treated fish to 68%, 59% and 49%, respectively. In vitro, the minimum inhibitory concentration (MIC) of 23 isolates of F. columnare was assayed. The majority of the isolates had an MIC value of 5 μg mL−1 (15 of the 23 isolates). Infected fish exhibited acute clinical signs similar to a natural infection. The skin had severe ulcerative necrotizing dermatitis and the muscles had severe necrotizing myositis. The gills had severe multifocal necrotizing branchitis. The results demonstrate that diquat would reduce mortalities caused by an acute columnaris infection.
Detection and identification of aquatic mycobacteria in formalin‐fixed, paraffin‐embedded fish tissues
Authors: Pourahmad F , Thompson K D , Adams A , Richards R H 
Published: April 2009

AbstractThe isolation of mycobacteria from field samples is problematic, and isolation of the bacterium is sometimes not even attempted. The detection of mycobacteria through traditional histology using formalin‐fixed, paraffin‐embedded (FFPE) tissues is neither sensitive nor specific. However, detection of mycobacterial DNA from FFPE specimens, suspected of being infected with mammalian mycobacteriosis, is a routine clinical procedure. In the present study, a polymerase chain reaction (PCR)‐based method was used to detect and identify mycobacteria in FFPE specimens sampled from fish suspected of being infected with fish mycobacteriosis. A total of 45 fish tissue samples, comprising of 12 tissue samples obtained from experimentally infected fish and the remainder from fish naturally infected with mycobacteria, were analysed using a PCR protocol which amplifies a fragment of the mycobacterial 65 kDa heat‐shock protein (hsp65) gene. PCR‐restriction enzyme analysis and/or sequencing were employed to further analyse the PCR amplicons. The PCR results were compared with those obtained by histology and culture. Mycobacterial DNA was detected in 34 of the 45 samples examined, of which 16 samples (47%) showed granulomatous reactions on histological examination. Using histology as the gold standard, no false‐negative PCR results were obtained. Also, considering the presence or absence of granulomas as a diagnostic criterion, the sensitivity and specificity of PCR in 42 of the FFPE tissues were 16/16 (100%) and 8/26 (∼30.8%), respectively. Corresponding microbiological cultures were available for 15 cases, of which 13 were pure Mycobacterium cultures. Of these, 13 were PCR positive (100% sensitivity and 50% specificity). The PCR‐based methods used here proved sensitive, specific and rapid for the detection of mycobacteria in routinely processed paraffin wax‐embedded and formalin‐fixed histological samples, and the results of the study suggest that this method has potential use in retrospective epidemiological studies.
Experimental study of the susceptibility of Atlantic cod, Gadus morhua (L.), to infection with an IPNV strain pathogenic for Atlantic salmon, Salmo salar L
Authors: Urquhart K , Bowden T J , Buckett B‐E , Garcia J , Fryer R J , Ellis A E 
Published: April 2009

AbstractIntraperitoneal (IP) injection, cohabitation and immersion routes of infection were used to determine if Atlantic cod, Gadus morhua (L.), of 1 and 3 g are susceptible to infectious pancreatic necrosis (IPN). Mortalities of cod injected IP were significantly higher when challenged with infectious pancreatic necrosis virus (IPNV) than with phosphate buffered saline. This is the first report of Atlantic cod mortalities caused by IPNV. Fish challenged by cohabitation had significantly higher mortalities than the controls, but mortalities of Atlantic cod challenged with IPNV by immersion were not significantly different from controls. Titres of IPNV in the tissues of infected fish were sometimes very high (range 102–1010 infectious units per gram of tissue) suggesting virus replication and titres of fish that died were generally higher than those of fish which survived. However, the relatively low mortality rates when challenged by cohabitation and immersion (20% and 17%, respectively), compared to the IP injection challenge (100%) suggest that 1 and 3 g cod have low susceptibility to IPN when challenged by more natural routes. These data strongly suggest that the cause of death of experimentally challenged cod was IPNV and further histological evidence for this came from 1 g cod challenged IP with IPNV in which the pancreas showed severe necrosis and heavy immunostaining for IPNV coincidentally with the peak of mortalities.
Depleted intestinal goblet cells and severe pathological changes in SCID mice infected with Heligmosomoides polygyrus
Authors: HASHIMOTO K. , UCHIKAWA R. , TEGOSHI T. , TAKEDA K. , YAMADA M. , ARIZONO N. 
Published: April 2009

SummaryTo determine the role of T cells and mast cells in intestinal pathology and immune expulsion of intestinal nematodes, worm burdens, goblet cell responses and villus structures were analysed in T‐ and B‐cell‐deficient severe combined immunodeficiency (SCID) mice, athymic nu/nu mice and mast cell deficient W/Wv mice after infection with the nematode Heligmosomoides polygyrus. SCID and nu/nu mice showed significantly higher worm burdens at week 9 post‐infection compared with the wild‐type controls. SCID and nu/nu mice showed compromised goblet cell hyperplasia and/or Muc 2 expression, indicating that both events are T‐cell dependant. On the other hand, the SCID mice showed increased pathology (villus atrophy and crypt hyperplasia) and increased numbers of proliferating cell nuclear antigen positive cells compared to the wild‐type controls. W/Wv mice, conversely, were able to expel the worms normally, had normal goblet cell hyperplasia, and did not demonstrate the changes in mucosal architecture seen in SCID mice, confirming that a normal mast cell response is not necessarily required for these changes. These results suggest that a functional T‐cell response, but not a mast cell response, is necessary for anti‐parasite responses, goblet cell function, and maintaining normal mucosal architecture.
Inhibitory role of toll‐like receptors agonists in Plasmodium yoelii liver stage development
Authors: CHEN J. , XU W. , ZHOU T. , DING Y. , DUAN J. , HUANG F. 
Published: April 2009

SummaryIt is well known that innate immune plays an important role in controlling the development of Plasmodium liver stage. However, little is known about the role of toll‐like receptors (TLR) signalling in the pre‐erythrocytic immunity against Plasmodium. Here, we found that pre‐treatment with individual TLR agonist pam3CSK4 (TLR2), poly(I:C) (TLR3), LPS (TLR4) and CpG (TLR9) could decrease significantly the liver malaria parasite load in mice for 58%, 63%, 75% and 88% respectively. Moreover, no parasitaemia was observed within 14 days in CpG group mice challenged with 100 sporozoites. At 24 h prior to CpG injection, administration of gadolinium chloride (GdCl3) led to the rebound of liver Plasmodium load through inhibiting selectively Kupffer cells (KC) phagocytosis capacity but failed to neutralize completely CpG‐induced immunity against malaria liver stage. Compared with the control, pre‐treatment of CpG up‐regulated hepatic pro‐inflammatory cytokines IL‐12, IFN‐γ and TNF‐α, but down‐regulated anti‐inflammatory cytokines IL‐10 and TGF‐β. Hence, our data demonstrated the inhibitory role of diverse TLR agonists in the Plasmodium development during pre‐erythrocytic stage. As the most robust agonist, CpG might inhibit the development of Plasmodium liver stage through regulation of intrahepatic inflammatory cytokines and enhancement of KC cells phagocytosis capacity.
Weed community characteristics and crop performance: a neighbourhood approach
Authors: POLLNAC F W , MAXWELL B D , MENALLED F D 
Published: April 2009

SummaryThe presence of weeds in crop fields often causes yield reductions. However, the effects of weed diversity have not been fully examined. This study tested the hypothesis that, holding density constant, increased weed species richness would decrease the effects of competition on spring wheat target plant performance. Measurements were taken from circular neighbourhoods (16.5 cm radius) with a single spring wheat plant surrounded by combinations of Setaria viridis, Avena fatua, Kochia scoparia, Thlaspi arvense and spring wheat plants, representing all combinations of neighbour species at four density levels. Using regression models, we found that species richness had no significant direct effect on spring wheat biomass, yield, or relative growth rate and that there were no significant neighbour species interaction terms. For weedy target plants, the presence of negative interaction terms suggested that increasing species richness had negative effects on growth of individual weed species. Additional analysis suggested that increased species richness may limit competitive ability of dominant weeds. Although we found no evidence of a direct effect of weed species richness on crop performance, increased weed species richness had no negative effect on spring wheat performance. Further, species richness of the weed community appears to influence weedy plant performance, which may offer a future opportunity to influence crop performance.
Demography of Salsola australis populations in the agricultural region of south‐west Australia
Authors: BORGER C P D , SCOTT J K , WALSH M , POWLES S B 
Published: April 2009

Summary Salsola australis is a widespread annual weed of broad‐scale cropping and pasture systems throughout Australia, and is of concern in the wheat belt of Western Australia. The population dynamics of S. australis was monitored at four sites in the Lake Grace district of Western Australia. At all sites, two to three cohorts emerged in summer and autumn or winter. While initial seedling density varied, density‐dependent mortality ensured that the total number of senesced plants at each site was not significantly different. Estimated seed production ranged from 95 to 19 596 seeds per plant, although seed viability was low (approximately 9% for seeds that were shed and 15% for seeds that were retained on the mature plants). Total annual seed production per unit area was highly variable within sites but was not significantly different between sites. These data will facilitate the development of improved control strategies for S. australis.
Assessment of management options for Salsola australis in south‐west Australia by transition matrix modelling
Authors: BORGER C P D , SCOTT J K , RENTON M , WALSH M , POWLES S B 
Published: April 2009

SummaryA matrix model of the life cycle of Salsola australis was constructed, based on population ecology data collected from the district of Lake Grace, Western Australia. The model was used to assess potential control strategies for this summer annual weed within the Western Australian broad acre grain cropping system. The population growth rate (λ) of S. australis in the absence of weed control strategies was 1.49 and was virtually unaffected by the dormant seedbank. However, λ increased to 8.21 if it was assumed that a constant number of seed immigrated into the area in question from neighbouring populations of S. australis, through farm‐scale seed dispersal. As a result, effective weed management depended on reducing seed dispersal. The model determined that burning all senesced, mobile plants in late autumn, combined with herbicide control of the largest cohorts of S. australis in summer and autumn, reduced population growth rate to 0.79. This control strategy resulted in a 66.1% chance of the population becoming extinct over 25 years. Management strategies are proposed based on the results of the models and further research is required to validate their effectiveness and practicality in the field.
Resistance to broomrape in wild lentils (Lens spp.)
Authors: Fernández‐Aparicio M. , Sillero J. C. , Rubiales D. 
Published: April 2009

Abstract Orobanche crenata, Orobanche aegyptiaca and Orobanche foetida constitute serious threats to grain legumes in the Mediterranean Basin. Lentil can be severely infected by O. crenata. It can also be damaged although with less virulence by O. aegyptiaca, and can only be slightly infected by O. foetida. Resistance breeding is hampered by scarcity of proper sources of resistance in cultivated lentil and of a reliable and practical screening procedure. A germplasm collection of 23 wild Lens spp. accessions was screened for resistance to O. crenata under field conditions. A wide range of responses was observed, from complete resistance to susceptibility. The higher levels of resistance were observed in accessions of Lens ervoides, Lens odemensis and Lens orientalis. Resistance of selected accessions proved to be mainly because of early hampered tubercle formation, with no observed necrosis of established tubercles. No differences were observed in levels of induction of broomrape germination, but necrosis of broomrape radicles was significant in some cases, particularly in the L. odemensis–O. foetida interaction. Escape because of the reduced root biomass diminishing the chance of contact between host and parasite was also observed in L. odemensis.
Ploidy manipulation in guinea grass (Panicum maximum Jacq., Poaceae) utilizing a Hybridization‐supplemented Apomixis‐components Partitioning Approach (HAPA)
Authors: Kaushal P. , Agrawal A. , Malaviya D. R. , Siddiqui S. A. , Roy A. K. 
Published: April 2009

AbstractPloidy manipulations are achieved by utilizing unreduced gametes, somatic chromosome doubling or haploidization. Apomixis, the asexual mode of reproduction through seeds, involves two of these phenomena viz., apomeiosis (unreduced embryo‐sac formation) and parthenogenesis (fertilization‐independent embryogenesis). The two components when partitioned may yield high frequencies of triploids and haploids, and thus, serve as a tool to manipulate ploidy levels when appropriately supplemented with hybridization schemes. Utilizing this Hybridization‐supplemented Apomixis‐components Partitioning Approach (HAPA), the largest ploidy series in a crop plant was generated in guinea grass (Panicum maximum Jacq.). Eighty‐nine diverse guinea grass accessions were characterized for their reproductive capacities to identify tetraploid (2n = 4x = 32) accession(s) with high apospory but reduced parthenogenetic capacity, thereby producing a high frequency of hexaploid seeds. Seeds from accession IG 04‐164 were utilized to produce a ploidy series by appropriately combining partitioned apomixis components and hybridizations in two seasonal cycles. We successfully obtained plants representing ploidies 3x, 4x, 5x, 6x, 8x and 9x, all derived from a single 4x progenitor. Production methodology, reproducibility and utilization of HAPA in cytogenetic and molecular studies are discussed.
Use of SSR markers to assess sexual vs. apomictic origin and ploidy level of breeding progeny derived from crosses of apple proliferation‐resistant Malus sieboldii and its hybrids with Malus × domestica cultivars
Authors: Bisognin C. , Seemüller E. , Citterio S. , Velasco R. , Grando M. S. , Jarausch W. 
Published: April 2009

AbstractTo obtain apple rootstocks resistant to apple proliferation and suitable to modern fruit growing, 24 cross‐combinations were performed over a 5‐year period using Malus sieboldii and its hybrids as donors of the resistance trait and standard apple rootstock Malus × domestica genotypes as donors of agronomic value. Breeding with these genotypes was achieved despite different degrees of apomixis and polyploidy. Sets of five to six locus‐specific microsatellite markers were identified for characterizing each progeny. Supported by flow cytometry these markers were applied to infer mode of reproduction, genomic constitution and ploidy level. Microsatellites allele composition identical to the maternal parent was revealed in 1668 of 3032 seedlings indicating seed formation through apomixis. Complete genetic recombination was found in 398 seedlings. The remaining hybrids displayed a higher ploidy than that of the parental plants which was consistent with the fertilization of unreduced egg cells. Thus, for each cross‐combination, microsatellite loci were identified which enabled a reliable prediction of the ploidy level. They can now be applied in routine screening to distinguish sexual from apomictic progeny.
A national cohort study of long‐course preoperative radiotherapy in primary fixed rectal cancer in Denmark
Authors: Bülow S. , Jensen L. H. , Altaf R. , Harling H. , Jensen M. , Laurberg S. , Lindegaard J. C. , Muhic A. , Vestermark L. ,   on behalf of the Danish Colorectal Cancer Group
Published: April 2009

AbstractObjective  Preoperative radiotherapy has been shown to enable a fixed rectal cancer to become resectable which in turn may result in long‐time survival. In this study, we analysed the outcome of long‐course preoperative radiotherapy in fixed rectal cancer in a national cohort including all Danish patients registered with primary inoperable rectal cancer and treated in the period May 2001 to December 2005.Method  The study was based on surgical and demographic data from a continuously updated and validated national database. In addition, retrospective data were retrieved from all departments of radiotherapy concerning technique of radiotherapy, dose and fractionation and use of concomitant chemotherapy. Outcome was determined by actuarial analysis of local control, disease‐free survival and overall survival.Results  A total of 258 patients with fixed rectal cancer received long‐course radiotherapy (> 45 Gy). The median age at diagnosis was 66 years (range: 32–85) and 185 (72%) patients were male. The resectability rate was 80%, and a R0 resection was obtained in 148 patients (57% of all patients and 61% of those operated). The 5‐year local recurrence rate for all patients was 5% (95% CI: 3–7%), and the actuarial distant recurrence rate was 41% (95% CI: 35–47%). The cumulative 5‐year disease‐free survival was 27% (95% CI: 22–32%) and overall 5‐year survival was 34% (95% CI: 29–39%).Conclusions  This study is the first population‐based report on outcome of preoperative long‐course radiotherapy in a large unselected patient group with clinically fixed rectal cancer. Most patients could be resected with the intention of cure and one in three was alive after 5 years.