Metaphors as models: Towards a typology of metaphor in ancient science

Metaphors play a crucial role in the understanding of science. Since antiquity, metaphors have been used in technical texts to describe structures unknown or unnamed; besides establishing a terminology of science, metaphors are also important for the expression of concepts. However, a concise terminology to classify metaphors in the language of science has not been established yet. But in the context of studying the history of a science and its concepts, a precise typology of metaphors can be helpful. Metaphors have a lot in common with models in science, as has been observed already. In this paper, therefore, I suggest a typology of metaphor in ancient science to fill this terminological gap by using concepts applied to the classification of models in science, as coined by Rom Harré. I propose to differentiate between homeoconceptual metaphors (with the same conceptual frame between source and target) and paraconceptual metaphors (mapped via a different conceptual frame). Furthermore, functional and structural aspects of metaphors in ancient science are taken into account. Case studies from ancient texts displaying metaphors in ancient science are presented and classified following the outlined typology of metaphors

Thermoregulation und Temperaturschwankungen – zum Umgang mit Fachbegriffen im Ökologieunterricht

oai:biejournals.de:article/1625Das Verständnis der Terminologie einer Naturwissenschaft ist essentiell für eine erfolgreiche Teilnahme am Unterricht. Fachspezifische Begriffe sollen dabei nicht additiv, sondern am konkreten Fall gelernt werden. Der vorliegende Beitrag gibt zunächst eine problemorientierte Übersicht über Aufgaben und Lösungsvorschläge zu dem Phänomen der Thermoregulation bei Lebewesen und zeigt, wie uneinheitlich die dabei verwendeten Fachbegriffe homoiotherm/poikilotherm bzw. endo- und ektotherm in verschiedenen Lehrbüchern und Lehrmaterial präsentiert werden. Daran anschließend wird kurz diskutiert, unter welchen Bedingungen diese Begriffe im Unterricht eingeführt werden sollten und wobei es darauf zu achten gilt

Aristotle's lobster: the image in the text

The Anatomai, a lost work written by Aristotle, must have contained a collection of various drawings and figures of species as well as their organs. In his texts (mainly the Historia animalium), Aristotle is often referring to the drawings after the description of species. Our study applies the method of the comparative view (‘Vergleichendes Sehen’) to provide an access to and reconstruction of Aristotle’s lost illustrations based on his textual descriptions. As an example, we chose the treatment of the European lobster (Homarus gammarus L., 1758) in the Aristotelian corpus as a case study. First, we analyse the etymology of the Greek term astakós referring to the lobster and provide an overview on the putative synonyms. Second, we confront the textual basis of the description with several questions concerning the degree of abstraction, the relation between text and image, and the spatial orientation of the image. Finally, we present a step-by-step reconstruction of Aristotle’s illustrations of the lobster based on the various passages dealing with its anatomy in the text of the Historia animalium. The problems which arise by a confrontation of the textual basis with hypothetical images are discussed at a more general level. We conclude that this kind of a text-based image reconstruction is only possible if the object described by Aristotle is unambiguously identifiable and still visually accessible

Exercise Improves Outcomes of Surgery on Fatty Liver in Mice: A Novel Effect Mediated by the AMPK Pathway.

OBJECTIVE To investigate whether exercise improves outcomes of surgery on fatty liver, and whether pharmacological approaches can substitute exercising programs. SUMMARY OF BACKGROUND DATA Steatosis is the hepatic manifestation of the metabolic syndrome, and decreases the liver's ability to handle inflammatory stress or to regenerate after tissue loss. Exercise activates adenosine monophosphate-activated kinase (AMPK) and mitigates steatosis; however, its impact on ischemia-reperfusion injury and regeneration is unknown. METHODS We used a mouse model of simple, diet-induced steatosis and assessed the impact of exercise on metabolic parameters, ischemia-reperfusion injury and regeneration after hepatectomy. The same parameters were evaluated after treatment of mice with the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR). Mice on a control diet served as age-matched controls. RESULTS A 4-week-exercising program reversed steatosis, lowered insulin levels, and improved glucose tolerance. Exercise markedly enhanced the ischemic tolerance and the regenerative capacity of fatty liver. Replacing exercise with AICAR was sufficient to replicate the above benefits. Both exercise and AICAR improved survival after extended hepatectomy in mice challenged with a Western diet, indicating protection from resection-induced liver failure. CONCLUSIONS Exercise efficiently counteracts the metabolic, ischemic, and regenerative deficits of fatty liver. AICAR acts as an exercise mimetic in settings of fatty liver disease, an important finding given the compliance issues associated with exercise. Exercising, or its substitution through AICAR, may provide a feasible strategy to negate the hepatic consequences of energy-rich diet, and has the potential to extend the application of liver surgery if confirmed in humans

Signal phylogénétique dans les caractères de l’ Histoire des Animaux d’Aristote

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Signal phylogénétique dans les caractères de l’<i>Histoire des Animaux</i> d’Aristote

L’influent philosophe grec Aristote (384-322 avant notre ère) est presque unanimement reconnu comme le fondateur de la zoologie. On s’accorde à dire qu’il s’intéressait aux attributs des animaux, mais le fait qu’il ait ou non essayé de développer une taxonomie zoologique reste controversé. Fürst von Lieven et Humar ont compilé une matrice de données à partir de l’Histoire des Animaux d’Aristote et ont montré, par une analyse de parcimonie publiée en 2008, que ces données produisaient une hiérarchie qui correspondait à plusieurs taxons reconnus par Aristote. Cependant, leur analyse laisse certaines questions en suspens car des données aléatoires peuvent parfois aboutir à des arbres assez résolus. Dans cette étude, nous mettons à jour les scores de nombreuses cellules et ajoutons quatre nouveaux caractères à la matrice de données (147 taxons notés pour 161 caractères) et citons des passages de l’Historia animalium d’Aristote pour justifier ces changements. Nous confirmons la présence d’un signal phylogénétique dans ces données par un test utilisant l’asymétrie dans la distribution de longueur d’un million d’arbres aléatoires, qui montre que de nombreux caractères discutés par Aristote étaient systématiquement pertinents. Nos analyses de parcimonie sur la matrice mise à jour retrouvent beaucoup plus d’arbres que ceux rapportés par Fürst von Lieven et Humar, mais leur consensus inclut de nombreux taxons qu’Aristote a reconnus et apparemment nommés pour la première fois, comme les selachē (sélaciens) et les dithyra (Bivalvia Linnaeus, 1758). Cette étude suggère que même si la taxonomie n’était visiblement pas le principal intérêt d’Aristote dans Historia animalium, elle faisait probablement partie de ses intérêts secondaires. Ces résultats peuvent ouvrir la voie à d’autres études taxonomiques dans les écrits zoologiques d’Aristote en général. Bien qu’elles soient presque périphériques dans les écrits d’Aristote, ses contributions taxonomiques sont clairement des réalisations majeures.The influential Greek philosopher Aristotle (384-322 BCE) is almost unanimously acclaimed as the founder of zoology. There is a consensus that he was interested in attributes of animals, but whether or not he tried to develop a zoological taxonomy remains controversial. Fürst von Lieven and Humar compiled a data matrix from Aristotle’s Historia animalium and showed, through a parsimony analysis published in 2008, that these data produced a hierarchy that matched several taxa recognized by Aristotle. However, their analysis leaves some questions unanswered because random data can sometimes yield fairly resolved trees. In this study, we update the scores of many cells and add four new characters to the data matrix (147 taxa scored for 161 characters) and quote passages from Aristotle’s Historia animalium to justify these changes. We confirm the presence of a phylogenetic signal in these data through a test using skewness in length distribution of a million random trees, which shows that many of the characters discussed by Aristotle were systematically relevant. Our parsimony analyses on the updated matrix recover far more trees than reported by Fürst von Lieven and Humar, but their consensus includes many taxa that Aristotle recognized and apparently named for the first time, such as selachē (selachians) and dithyra (Bivalvia Linnaeus, 1758). This study suggests that even though taxonomy was obviously not Aristotle’s chief interest in Historia animalium, it was probably among his secondary interests. These results may pave the way for further taxonomic studies in Aristotle’s zoological writings in general. Despite being almost peripheral to Aristotle’s writings, his taxonomic contributions are clearly major achievements.</p

Exploration of the Transcriptional Landscape of ALPPS Reveals the Pathways of Accelerated Liver Regeneration

Background and Aims: ALPPS (associating liver partition and portal vein ligation for staged hepatectomy), a novel 2-staged hepatectomy, dramatically accelerates liver regeneration and thus enables extensive liver tumor resection. The signaling networks underlying the ALPPS-induced accelerated regeneration process are largely unknown. Methods: We performed transcriptome profiling (TP) of liver tissue obtained from a mouse model of ALPPS, standard hepatectomy (68% model), and additional control surgeries (sham, PVL and Tx). We also performed TP using human liver biopsies (n = 5) taken from the occluded lobe and the future liver remnant (FLR) during the first step of ALPPS surgery (4–5 h apart). We used Oncofinder computational tools, which covers 378 ISPs, for unsupervised, unbiased quantification of ISP activity. Results: Gene expression cluster analysis revealed an ALPPS specific signature: the IGF1R Signaling Pathway (Cell survival), the ILK Pathway (Induced cell proliferation), and the IL-10 Pathway (Stability determination) were significantly enriched, whereas the activity of the Interferon Pathway (Transcription) was reduced (p < 0.05). Further, the PAK- and ILK-associated ISPs were activated at an earlier time point, reflecting significant acceleration of liver regeneration (p < 0.001). These pathways, which were also recovered in human liver biopsies, control cell growth and proliferation, inflammatory response, and hypoxia-related processes. Conclusions: ALPPS is not a straightforward addition of portal vein ligation (PVL) plus transection—it is more. The early stages of normal and accelerated liver regeneration are clearly discernible by a significantly increased and earlier activation of a small number of signaling pathways. Compounds mimicking these responses may help to improve the ALPPS method and further reduce the hospitalization time of the patient

Novel Benefits of Remote Ischemic Preconditioning Through VEGF-dependent Protection From Resection-induced Liver Failure in the Mouse

OBJECTIVE To investigate the impact of remote ischemic preconditioning (RIPC) on liver regeneration after major hepatectomy. SUMMARY BACKGROUND DATA RIPC is a strategy applied at remote sites to mitigate ischemic injury. Unlike other preconditioning approaches, RIPC spares target organs as it acts via systemic VEGF elevations. In the liver, however, VEGF is an important driver of regeneration following resection. Therefore, RIPC may have pro-regenerative effects. METHODS RIPC was applied to C57BL/6 mice through intermittent clamping of the femoral vessels prior to standard 68%-hepatectomy or extended 86%-hepatectomy, with the latter causing liver failure and impaired survival. Liver regeneration was assessed through weight gain, proliferative markers (Ki67, pH3, mitoses), cell cycle-associated molecules, and survival. The role of the VEGF-ID1-WNT2 signaling axis was assessed through WIF1 (a WNT antagonist) and recombinant WNT2 injected prior to hepatectomy. RESULTS RIPC did not affect regeneration after 68%-hepatectomy, but improved liver weight gain and hepatocyte mitoses after 86%-hepatectomy. Importantly, RIPC raised survival from 40% to 80% after 86%-hepatectomy, indicating the promotion of functional recovery. Mechanistically, the RIPC-induced elevations in VEGF were accompanied by increases in the endothelial transcription factor Id1, its target WNT2, and its hepatocellular effector β-catenin. WIF1 injection prior to 86%-hepatectomy abrogated the RIPC benefits, while recombinant WNT2 had pro-regenerative effects akin to RIPC. CONCLUSION RIPC improves the regenerative capacity of marginal liver remnants in a VEGF-dependent way. If confirmed in patients, RIPC may become the preconditioning strategy of choice in the setting of extended liver resections

Phase Ib dose-escalation study of the hypoxia-modifier Myo-inositol trispyrophosphate in patients with hepatopancreatobiliary tumors

Hypoxia is prominent in solid tumors and a recognized driver of malignancy. Thus far, targeting tumor hypoxia has remained unsuccessful. Myo-inositol trispyrophosphate (ITPP) is a re-oxygenating compound without apparent toxicity. In preclinical models, ITPP potentiates the efficacy of subsequent chemotherapy through vascular normalization. Here, we report the results of an unrandomized, open-labeled, 3 + 3 dose-escalation phase Ib study (NCT02528526) including 28 patients with advanced primary hepatopancreatobiliary malignancies and liver metastases of colorectal cancer receiving nine 8h-infusions of ITPP over three weeks across eight dose levels (1'866-14'500 mg/m2/dose), followed by standard chemotherapy. Primary objectives are assessment of the safety and tolerability and establishment of the maximum tolerated dose, while secondary objectives include assessment of pharmacokinetics, antitumor activity via radiological evaluation and assessment of circulatory tumor-specific and angiogenic markers. The maximum tolerated dose is 12,390 mg/m2, and ITPP treatment results in 32 treatment-related toxicities (mostly hypercalcemia) that require little or no intervention. 52% of patients have morphological disease stabilization under ITPP monotherapy. Following subsequent chemotherapy, 10% show partial responses while 60% have stable disease. Decreases in angiogenic markers are noted in ∼60% of patients after ITPP and tend to correlate with responses and survival after chemotherapy