264 research outputs found
The Swedish Public Lending Right PLR
No full texterspective [80][upps-01.gif] This is a thesis on the Swedish Public Lending Right PLR, from a historical perspective. Some of the questions which are investigated in this thesis are: why did the State decide to introduce a PLR and why did it take about 20 years to make the decision? The question why the PLR was not introduced on a copyright basis is also discussed. The focus of this study is during the period of 1934-1956 and it is a literature-study. Mainly there are four reports made by different committees that have been examined. The answer to why it took about 20 years was that the question of a PLR was complicated since it involved two different political areas: the cultural and the legal. The explanation to why a PLR was introduced was because the State could afford it. It was also introduced because the arguments proclaimed by the Swedish Author Association, {Sveriges Författareförening, of how the libraries had a damaging effect of the authors finances, also became the opinion of the State. The Swedish government never took the alternative, to let the borrowers pay for the PLR, into consideration. No legal adjustment in the copyright law took place though. That was probably because it would lead to difficulties, since the government wanted to make a difference between which author that should receive a PLR or not. Chiefly the State wanted to support Swedish authors who wrote fiction.Uppsatsnivå:
Modification of a photosynthetic light-response (PLR) model for modeling the vertical gradient in the response of crown PLR curves
No full textThe photosynthetic light-response (PLR) curve is a mathematical description of a single biochemical process that has been widely applied in many ecophysiological models. For trees, the heterogeneity of PLR curves within the crown is significant but rarely modeled by mathematical techniques. This paper establishes a modified model for estimating crown PLR curves based on PLR functions by linking the parameters of the PLR functions to leaf nitrogen (N), specific leaf area (SLA) and relative depth into the crown (RDINC). The modified models were assessed by considering the goodness of fit (adjusted coefficient of determination, Ra2; root mean square error, RMSE; and Akaike information criterion, AIC) and model structure. Significant correlations were observed between the parameters of PLR functions and N, SLA and RDINC. The optimal modified PLR model, by linking RDINC into a modified Mitscherlich function, fit well due to its simple and easily understood structure. Therefore, it is feasible to simultaneously estimate the multilayered and varied PLR curves of the tree crown.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Correction: Determination of metal ion content of beverages and estimation of target hazard quotients: a comparative study
No full textThis is a correction to the following paper: Hague T, Petroczi A, Andrews PR, Barker J, Naughton DP: Determination of metal ion content of beverages and estimation of target hazard quotients: a comparative study. Chem Central J 2008, 2:13
Review article: An analysis of the pharmacological rationale for selecting drugs to inhibit vomiting or increase gastric emptying during treatment of gastroparesis.
No full textBACKGROUND: Drugs which can inhibit nausea/vomiting and/or increase gastric emptying are used to treat gastroparesis, mostly 'off-label'. Within each category, they act at different targets and modulate different physiological mechanisms. AIMS: Address the questions: In gastroparesis, why should blocking one pathway causing vomiting, be more appropriate than another? Why might increasing gastric emptying via one mechanism be more appropriate than another? METHODS: Drugs used clinically were identified via consensus opinions and reviews, excluding the poorly characterised. Their pharmacology was defined, mapped to mechanisms influencing vomiting and gastric emptying, and rationale developed for therapeutic use. RESULTS: Vomiting: Rationale for 5-HT3 , D2 , H1 or muscarinic antagonists, and mirtazapine, amitriptyline, nortriptyline, are poor. Arguments for inhibiting central consequences of vagal afferent transmission by NK1 antagonism are complicated by doubts over effects on nausea. Gastric emptying: Confusion emerges because of side-effects of drugs increasing gastric emptying: Metoclopramide (5-HT4 agonist, D2 and 5-HT3 antagonist; also blocks some emetic stimuli and causes tardive dyskinesia) and Erythromycin (high-efficacy motilin agonist, requiring low doses to minimise side-effects). Limited trials with selective 5-HT4 agonists indicate variable efficacy. CONCLUSIONS: Several drug classes inhibiting vomiting have no scientific rationale. NK1 antagonism has rationale but complicated by limited efficacy against nausea. Studies must resolve variable efficacy of selective 5-HT4 agonists and apparent superiority over motilin agonists. Overall, lack of robust activity indicates a need for novel approaches targeting nausea (e.g., modulating gastric pacemaker or vagal activity, use of receptor agonists or new targets such as GDF15) and objective assessments of nausea
Advice on avoiding the Valley of Death: insights from a 3Rs model of aversive and emetic compound identification.
No full text
Why Can't Rodents Vomit? A Comparative Behavioral, Anatomical, and Physiological Study
No full textThe vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity-key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed. © 2013 Horn et al
Investigating the Effect of Emetic Compounds on Chemotaxis in Dictyostelium Identifies a Non-Sentient Model for Bitter and Hot Tastant Research.
No full textNovel chemical entities (NCEs) may be investigated for emetic liability in a range of unpleasant experiments involving retching, vomiting or conditioned taste aversion/food avoidance in sentient animals. We have used a range of compounds with known emetic /aversive properties to examine the possibility of using the social amoeba, Dictyostelium discoideum, for research into identifying and understanding emetic liability, and hence reduce adverse animal experimentation in this area. Twenty eight emetic or taste aversive compounds were employed to investigate the acute (10 min) effect of compounds on Dictyostelium cell behaviour (shape, speed and direction of movement) in a shallow chemotaxic gradient (Dunn chamber). Compound concentrations were chosen based on those previously reported to be emetic or aversive in in vivo studies and results were recorded and quantified by automated image analysis. Dictyostelium cell motility was rapidly and strongly inhibited by four structurally distinct tastants (three bitter tasting compounds--denatonium benzoate, quinine hydrochloride, phenylthiourea, and the pungent constituent of chilli peppers--capsaicin). In addition, stomach irritants (copper chloride and copper sulphate), and a phosphodiesterase IV inhibitor also rapidly blocked movement. A concentration-dependant relationship was established for five of these compounds, showing potency of inhibition as capsaicin (IC(50) = 11.9 ± 4.0 µM) > quinine hydrochloride (IC(50) = 44.3 ± 6.8 µM) > denatonium benzoate (IC(50) = 129 ± 4 µM) > phenylthiourea (IC(50) = 366 ± 5 µM) > copper sulphate (IC(50) = 1433 ± 3 µM). In contrast, 21 compounds within the cytotoxic and receptor agonist/antagonist classes did not affect cell behaviour. Further analysis of bitter and pungent compounds showed that the effect on cell behaviour was reversible and not cytotoxic, suggesting an uncharacterised molecular mechanism of action for these compounds. These results therefore demonstrate that Dictyostelium has potential as a non-sentient model in the analysis of the molecular effects of tastants, although it has limited utility in identification of emetic agents in general
Comparison of NLR,LMR,PLR, RDW, and Platelet count in hematological malignancies at baseline and at intervals of 2 months in patients undergoing chemotherapy
No full textBlood cancer has become quite common in all age groups, worldwide. The cancer ranges from acute life
threatening leukemias to indolent chronic leukemias, Lymphoma spillovers causing morbidity and mortality to
slow-growing indolent lymphomas. Since blood is present everywhere in the body hence the spread of
hematological malignancies is massive. Chemotherapy is expensive and a must to treat blood cancers. However,
the ancillary workups like flowcytometry etc in prognosticating and diagnosing blood cancers become quite
cumbersome and heavy on the pocket for an average Indian. Therefore, the authors planned the study aimed at
analyzing-
-Trend in NLR,LMR, PLR RDW, Platelet count at baseline
-Trend in NLR,LMR, PLR RDW, Platelet count 2 months post-chemotherapy
-Comparison between 2 parameters for any significant change
The study was carried out on 11 cases as a prospective case-based study of 11 cases where pre and post-values of
chemotherapy cases of newly diagnosed blood cancer cases were available with the author. The baseline CBC and
post-induction 1 st CBC were used to record the variables under study and latest SPSS software was used to come
to a conclusion through the results.
The findings stated that there was a decline in NLR, PLR and platelet count at follow-up as compared to baseline
and an increase in LMR and RDW at follow-up as compared to baseline, however, the difference was significant
statistically only for PLR (p=0.028) and near significant (p=0.059) for platelet count.
Hence in view of significant findings seen only in 11 cases a larger cohort may be used to correlate these findings
with follow up of such cases
Severe chronic neck injury caused by a snare in a Coyote, Canis latrans
No full textA two-year-old male Coyote, Canis latrans, in poor body condition was found in a moribund state with a snare deeply embedded in the ventral portion of its neck, more than a month after the official end of the trapping season on Prince Edward Island. This snare had presumably malfunctioned, and the cable had cut through the soft tissues of the neck as well as the trachea and had obstructed both jugular veins and both common carotid arteries but had largely spared both vagosympathetic trunks. Cases like this illustrate the need to continue to work on improving the efficiency of trapping methods, through research and trapper education.PT: J; CR: *DEP FOR AFF INT T, 1997, AGR INT HUM TRAPP ST, P31 ANDREWS PLR, 1992, NEUROANATOMY PHYSL A, P280 BENZ GW, 2001, CAN FIELD NAT, V115, P506 BODDICKER ML, 1982, P VERT PEST C, V10, P50 ESLER M, 1992, CLIN AUTON RES, V2, P133 EVANS HE, 1993, MILLERS ANATOMY DOG, P219 GUTHERY FS, 1978, J WILDLIFE MANAGE, V42, P457 GUYTON AC, 1996, TXB MED PHYSL, P107 PHILLIPS RL, 1996, WILDLIFE SOC B, V24, P107 PROULX G, 1990, WILDLIFE SOC B, V18, P27 PROULX G, 1991, N AM WILDLIFE NATURA, V56, P387 SCOTT DW, 2001, MULLER KIRKS SMALL A, P1 WHISNANT JP, 1956, AM J PHYSIOL, V186, P275; NR: 13; TC: 0; J9: CAN FIELD-NATUR; PG: 4; GA: 927NLSource type: Electronic(1
- …
