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In this paper, we investigate an arithmetic analogue of the gonality of a smooth projective curve |$C$| over a number field |$k$|⁠ : the minimal |$e$| such that there are infinitely many points |$P \in C(\bar{k})$| with |$[k(P):k] \leqslant e$|⁠. Developing techniques that make use of an auxiliary smooth surface containing the curve, we show that this invariant can take any value subject to constraints imposed by the gonality. Building on work of Debarre–Klassen, we show that this invariant is equal to the gonality for all sufficiently ample curves on a surface |$S$| with trivial irregularity. [ABSTRACT FROM AUTHOR]

Management of stressors requires an understanding of how multiple stressors interact, how different species respond to those interactions and the underlying mechanisms driving observed patterns in species' responses. Salinization and rising temperatures are two pertinent stressors predicted to intensify in freshwater ecosystems, posing concern for how susceptible organisms achieve and maintain homeostasis (i.e. allostasis). Here, glucocorticoid hormones (e.g. cortisol), responsible for mobilizing energy (e.g. glucose) to relevant physiological processes for the duration of stressors, are liable to vary in response to the duration and severity of salinization and temperature rises. With field and laboratory studies, we evaluated how both salinity and temperature influence basal and stress-reactive cortisol and glucose levels in age 1+ mottled sculpin (Cottus bairdii), mountain sucker (Catostomus platyrhynchus) and Colorado River cutthroat trout (Oncorhynchus clarki pleuriticus). We found that temperature generally had the greatest effect on cortisol and glucose concentrations and the effect of salinity was often temperature dependent. We also found that when individuals were chronically exposed to higher salinities, baseline concentrations of cortisol and glucose usually declined as salinity increased. Reductions in baseline concentrations facilitated stronger stress reactivity for cortisol and glucose when exposed to additional stressors, which weakened as temperatures increased. Controlled temperatures near the species' thermal maxima became the overriding factor regulating fish physiology, resulting in inhibitory responses. With projected increases in freshwater salinization and temperatures, efforts to reduce the negative effects of increasing temperatures (i.e. increased refuge habitats and riparian cover) could moderate the inhibitory effects of temperature-dependent effects of salinization for freshwater fishes. [ABSTRACT FROM AUTHOR]

Spatial and temporal variation in stoichiometric and stable isotope ratios of animals contains ecological information that we are just beginning to understand. In both field and lab studies, stoichiometric or isotopic ratios are related to physiological mechanisms underlying nutrition or stress. Conservation and ecosystem ecology may be informed by isotopic data that can be rapidly and non-lethally collected from wild animals, especially where human activity leaves an isotopic signature (e.g. via introduction of chemical fertilizers, ornamental or other non-native plants or organic detritus). We examined spatial and temporal variation in stoichiometric and stable isotope ratios of the toes of Uta stansburiana (side-blotched lizards) living in urban and rural areas in and around St. George, Utah. We found substantial spatial and temporal variation as well as context-dependent co-variation with reproductive physiological parameters, although certain key predictions such as the relationship between δ15N and body condition were not supported. We suggest that landscape change through urbanization can have profound effects on wild animal physiology and that stoichiometric and stable isotope ratios can provide unique insights into the mechanisms underlying these processes. [ABSTRACT FROM AUTHOR]

Objectives: By convention, 500 cells are counted for bone marrow aspirate differentials. Evidence supporting such a cutoff is lacking. We hypothesized that 300-cell counts could be sufficient.Methods: Cell count results from 165 cases, for which values were recorded at 300 and 500 cells, were analyzed. We tested for statistical differences and changes in diagnostic classification between the two cutoffs.Results: Three hundred cell counts did not produce diagnostically different results, particularly for myeloblasts and plasma cells, where cell percentages are critical for disease classification. Method comparison analysis did not reach statistical significance for any cell type when comparing the two methods. Bias plots showed narrow, even spread about the mean bias. Contingency table analysis yielded no significant diagnostic discrepancies.Conclusions: Performing differential counts on 300 cells would produce clinically and statistically similar results to 500 cells. Reducing the cell number counted has potential cost/labor reductions without affecting quality of care. [ABSTRACT FROM AUTHOR]

The article examines the role of the international wildlife law in the implementation of environmental conservation efforts. Other topics include the limitations of international wildlife regimes, legal instruments for wildlife conservation, and situations in which such laws can improve the application of conservation policies.

The immune system is a critical component of health and fitness, whereby organisms must maintain sufficient health to survive to reproduce. Because of the key role of immunity in an organism's fitness, the use of immunological indices is widespread. However, there is a paucity of empirical support for the best way to interpret immunological data, and the internal energetic state of the organism, as well as the external environmental pressures it faces, are often not considered concurrently. A stronger immune response is not always beneficial to the organism; a more attenuated response may ultimately lead to improved fitness if the animal incurs fewer performance costs on competing systems, especially reproduction. Additionally, the external pressures animals encounter (such as anthropogenic disturbance) must be considered along with the animal's internal state. A synthesis of results addressing resource allocation between the immune and reproductive systems is presented using a well-studied organism, the side-blotched lizard, from a combination of field and laboratory studies under varying environmental conditions. Specifically, experiments involving specific immune, reproductive, metabolic, and performance costs in a laboratory setting are discussed, as well as associated demographic trade-offs between survival and reproductive success, demonstrating essential links between immunity and the population. [ABSTRACT FROM AUTHOR]

Objectives As a result of the introduction of rapid benchtop sequencers, the time required to subculture a bacterial pathogen to extract sufficient DNA for library preparation can now exceed the time to sequence said DNA. We have eliminated this rate-limiting step by developing a protocol to generate DNA libraries for whole-genome sequencing directly from single bacterial colonies grown on primary culture plates. Methods We developed our protocol using single colonies of 17 bacterial pathogens responsible for severe human infection that were grown using standard diagnostic media and incubation conditions. We then applied this method to four clinical scenarios that currently require time-consuming reference laboratory tests: full identification and genotyping of salmonellae; identification of blaNDM-1, a highly transmissible carbapenemase resistance gene, in Klebsiella pneumoniae; detection of genes encoding staphylococcal toxins associated with specific disease syndromes; and monitoring of vaccine targets to detect vaccine escape in Neisseria meningitidis. Results We validated our single-colony whole-genome sequencing protocol for all 40 combinations of pathogen and selective, non-selective or indicator media tested in this study. Moreover, we demonstrated the clinical value of this method compared with current reference laboratory tests. Conclusions This advance will facilitate the implementation of whole-genome sequencing into diagnostic and public health microbiology. [ABSTRACT FROM PUBLISHER]

The article provides information on the crisis encountered by the British Film Institute (BFI) in 1970 in London, England. These include the tensions happening within the Board of Governors, between governors and management, between management and staffs. A group of BFI members was asking for change and if possible to change the entire Board of Governors. At the end, the chairman of the board has resigned as well as Paddy Whannel, the charismatic head of BFI's Educational Department. According to a report, the crisis occurred when BFI was recreated under its new Chairman of Governors, Dennis Forman, where it had grown but was not able to keep up with changes in the surrounding culture.

Fumonisin mycotoxicosis in pigs causes a decrease in mean aortic pressure, an increase in mean pulmonary arterial pressure, and increases in serum concentrations of sphinganine (3.2 μM) and sphingosine (1.4 μM). To determine a causal relationship between the hemodynamic changes and sphingolipid alterations, we examined the in vitro effects of sphinganine, sphingosine, and sphingosine-1-phosphate on porcine aortic and pulmonary arterial rings. Both sphinganine and sphingosine relaxed uncontracted and phenylephrine-contracted aortic rings at ≥10 μM and ≥1 μM, respectively. Sphingosine (≥10 μM) relaxed uncontracted and phenylephrine-contracted pulmonary arterial rings, whereas sphingosine-1-phosphate (10 μM) contracted pulmonary arterial rings. Sphingosine (3 μM) also impaired the contractile response of pulmonary artery rings to 60 mM KCl. The results suggested that the systemic hypotension caused by fumonisin is mediated, in part, by increases in serum sphinganine and sphingosine concentrations, and the pulmonary hypertension is mediated, in part, by increased sphingosine-1-phosphate concentrations. [ABSTRACT FROM AUTHOR]

Fumonisin B1 is the most toxic and commonly occurring form of a group of mycotoxins that alter sphingolipid biosynthesis and induce leukoencephalomalacia in horses and pulmonary edema in pigs. Purified fumonisin B1 (1 mg/kg, iv, daily) increased serum sphinganine and sphingosine concentrations and decreased cardiovascular function in pigs within 5 days. We therefore examined whether the same dosage schedule of fumonisin B1 produced a similar effect in calves. Ten milk-fed male Holstein calves were instrumented to obtain blood and cardiovascular measurements. Treated calves (n = 5) were administered purified fumonisin B1 at 1 mg/kg, iv, daily for 7 days and controls (n = 5) were administered 10 ml 0.9% NaCl, iv, daily. Each calf was euthanized on day 7. In treated calves, serum sphinganine concentration increased from day 3 onward (day 7, 0.237 ± 0.388 μmol/l; baseline, 0.010 ± 0.007 μmol/l; mean ± SD), whereas, serum sphingosine concentration was unchanged (day 7, 0.044 ± 0.065 μmol/l; baseline, 0.021 ± 0.025 μmol/l). Heart rate, cardiac output, stroke volume, mean arterial pressure, mean pulmonary artery pressure, pulmonary artery wedge pressure, central venous pressure, plasma volume, base-apex electrocardiogram, arterial Po2, and systemic oxygen delivery were unchanged in treated and control calves. Fumonisin-treated calves developed metabolic acidosis (arterial blood pH, 7.27 ± 0.11; base excess, –9.1 ± 7.6 mEq/l), but all survived for 7 days. We conclude that calves are more resistant to fumonisin B1 cardiovascular toxicity than pigs. [ABSTRACT FROM PUBLISHER]

Fumonisins are mycotoxins produced by Fusarium verticillioides, which induce acute pulmonary edema in swine. We previously reported that ingestion of fumonisin-containing culture material decreases cardiovascular function in swine (1996,a,b; Fundam. Appl. Toxicol. 31, 169–172; 33, 140–148; 1999, Am. J Vet. Res. 60, 1291–1300). The main purpose of this study was to confirm that fumonisin B1 was responsible for the observed cardiovascular changes. Treated pigs (n = 6) were given daily intravenous injections of purified fumonisin B1 at 1 mg/kg for 4 days, while controls (n = 6) were injected with equal volumes of saline. On day 5, pigs were anesthetized with butorphanol-chloralose and instrumented for hemodynamic studies. Terminally, bronchoalveolar lavage was performed on each pig to determine the relative permeability index of the pulmonary endothelium. Fumonisin B1-treated pigs had marked decreases in the maximal rate of change of left ventricular pressure (dP/dtmax), mean aortic pressure, cardiac output, and arterial pO2, accompanied by increases in mean pulmonary artery pressure, oxygen extraction ratio, and blood hemoglobin concentration. Plasma and left ventricular sphingosine and sphinganine concentrations were markedly increased in treated pigs at day 5; however, there was no difference in the relative permeability index between groups. Serum cholesterol concentrations and activities of hepatic-derived enzymes were increased, and hepatocyte apoptosis and mitoses were present in the livers of fumonisin-treated pigs. In the lungs of treated pigs, there was proteinaceous edema and membranous accumulations in capillary endothelial cells. These results indicate that cardiovascular function is altered by fumonisin B1, and that fumonisin-induced pulmonary edema is caused by left-sided heart failure and not by altered endothelial permeability. Because of the potential for contamination of human foodstuffs by fumonisins, the cardiovascular toxicity of these compounds must be taken into consideration. [ABSTRACT FROM PUBLISHER]

Presents criticisms, interpretation and evaluation of the effects of gender and culture to the historical process. Importance of nationalism, racism, ethnicity, and religion in confrontations between societies; Gendered codes and symbols employed in anti-war rhetorics.

A personal narrative is presented which explores the author's viewpoint on filmography.

The article discusses the history of the cinema as the history of the 20th century due to the integration of cinema into the external histories of the century that cover economics and politics. Among the purposes served by the cinema since 1945 were showcasing feature films, entertainment and propaganda. The two powers television has which the cinema lacks are incorporation and instantaneity. There also had been a decline in cinemagoing throughout most of the developed world since the 1950s because most films are viewed on the television screen.

The article reviews the film "Radio On."

The article discusses the development of television broadcasting of sports. The author also explains that sport has been changed through the advent of television. He explains that television offers different attitudes and emotions in watching a certain sports since it offers a more comfortable surrogate. The author also explains that sport in television focuses more on individuals and useful interruptions such as replays, pauses and commentaries, thus, it fills up the spectator's need to identify with the person playing the sport.

The article reports that two consecutive study weekends were conducted in Newcastle, England on March 1977 which sought to give contexts for mediation and intervention in a defined area of film practice. It notes that the weekends had the purpose to analyze the variety of practices among independent British film-makers and from the groups which creates films as contributions to some political struggles to film-makers whose concerns concentrates on the limitations of illusionist narrative cinema.

The article focuses on the aspect of neo-realism in motion pictures. It examines the theoretical aspect of neo-realism in films and whether the concept is an aesthetic practice or an episode of cultural history. It examines the concept of neo-realism and its effects base on the anthology of writings from the magazine "Cinema Nuovo," which were published in the 1950s and concerned mostly with neo-realism. It mentions that the magazine played an important role in helping strengthen Italian film culture.

A letter to the editor is presented in response to the article on the film "The Searchers," in the Winter 1875/76 issue of "Screen Education."

Flavone-8-acetic acid (FAA), a new antitumor agent currently undergoing clinical trial, fails to inhibit the growth of early stage Lewis lung (ILL) tumors growing in the lung. However, the growth of advanced subscutaneous tumors, arising from inoculation of either the original in vivo LL line or a tissue culture-adapted cell line (LLTC) derived from the LL line was delayed significantly by FAA treatment. Comparision, by clonogenic survival assays, of the cytotoxic effect of FAA on LLTC cells demonstrated that most cell killing occurred between 2 and 8 hours following in vivo exposure but occurred to a much lesser extent and at later times following in vitro exposure. FAA was inactive against LLTC cells growing in vivo in diffusion chambers, suggesting that a host cellular component was necessay for activity. FAA was found to induce hemorrhagic necrosis in the advanced LL tumors, as well as in a number of human tumor xenografts growing in athymic mice. The human cell lines fom which the xenografts were derviced, as well as the LL tumor lines and P388 leukemia lines, were inhibited by FAA in vitro. However, the ranking of FAA activity in vivo did not parallel that observed in vitro. Together, these observations strongly suggest that FAA has an indirect mode of antitumor action. [J Natl Cancer Inst 1988;80:241–245] [ABSTRACT FROM PUBLISHER]

The presentation of N-formylated peptides to cytotoxic T cells is restricted to the mouse class I MHC molecule, H2-M3. Previous studies have shown that M3 is unable to present unformylated peptldes. We demonstrate that the unformylated ND1 peptide can sensitize M3-transfected fibroblasts for killing by ND1-specific cytotoxlc T cells. At 1 /M, both -formylated and unformylated ND1 peptides induced equivalent levels of killing. However, the concentrations required for half maximal killing differed by 104-fold, from 10-50 pM for N-formylated ND1 to 100 nM for unformylated ND1. The peptide binding groove of M3 differs from other class I molecules at three highly conserved positions: 34 (V→Q), 167 (W→L) and 171 (Y→F). Site-directed mutagenesis was used to determine the importance of these changes In the presentation of -formylated peptldes by M3. Cell lines expressing the mutations Q34V, L167W or F171Y all presented the -formylated ND1 peptide equally well to ND1-specific T cells. The -formylated ND1 peptide was also presented by a triple mutant, containing substitutions at all three positions. Q34, L167 and F171 are therefore not required individually, nor in combination, for the presentation of -formylated peptides by M3. However, all three point mutations did affect killing by alloreactive, M3-specific T cells. F171Y was the least damaging mutation, affecting only one of the two T cell lines tested. By contrast, both T cell lines failed to kill Q34V and L167W targets. Q34 and L167 are thus important determinants In the M3-speciflc CTL response. [ABSTRACT FROM PUBLISHER]

The author comments on Charles Eckert's article "The English Cine-Structuralists," which was published in the May-June 1973 issue of "Film Comment." He contends that what tempts Eckert to see a unity between the cine-structuralists is the affiliation from one English writer to the next and relationship to the non-English, non-cine structuralism of Claude Lévi-Strauss. He believes that classic auteur criticisms is aimed at vindicating the cinema as great art and the director/author as a great artist.

The article discusses various reports published within the issue, including one by Steve Neale and Mark Nash on the events during the 1977 Edinburgh Film Festival and another by Keith Tribe on the traditional representations of history on film.

The article discusses various reports published within the issue, including one by Christophe Dupin on the history of the British Film Institute (BFI) and another by Julia Knight and Peter Thomas on independent film distribution in Great Britain.

Reviewed: Hell No, We Won't Go: Vietnam Draft Resisters in Canada. Haig-Brown, Alan.

Reviewed: We Have Just Begun to Not Fight": An Oral History of Conscientious Objectors in Civilian Public Service during World War II. Frazer, Heather T. and O'Sullivan, John, ed.

The author reflects on the script of the film "Fortini/Cani" by Jean-Marie Straub and Daniele Huillet. He argues that the script has notable textual merits for its use of language and imagery. He comments on the script's use of characters and dialogue. The author also provides an overview of the script.

A response by Geoffrey Nowell-Smith to a letter to the editor about his review of "Screen Education 17" in the Spring 1976 issue of the journal is presented.

Fellow and President of the RAS, adventurous solar astronomer and distinguished spectroscopist. [ABSTRACT FROM AUTHOR]

The article presents an obituary for Masha Enzensberger, a collaborator on "Screen," journal.