159 research outputs found
Two Millennia of Making, Using, and Keeping Written Texts for Readers: Then, Now, and in the Future
The trade-off between heat tolerance and metabolic cost drives the bimodal life strategy at the air-water interface
The principle of oxygen and capacity limitation of thermal tolerance in ectotherms suggests that the long-term upper limits of an organism's thermal niche are equivalent to the upper limits of the organism's functional capacity for oxygen provision to tissues. Air-breathing ectotherms show wider thermal tolerances, since they can take advantage of the higher availability of oxygen in air than in water. Bimodal species move from aquatic to aerial media and switch between habitats in response to environmental variations such as cyclical or anomalous temperature fluctuations. Here we tested the prediction that bimodal species cope better with thermal stress than truly aquatic species using the crab Pachygrapsus marmoratus as a model species. When in water, oxygen consumption rates of P. marmoratus acutely rise during warming. Beyond a temperature threshold of 23â°C the crab's aerobic metabolism in air remains lower than in water. In parallel, the haemolymph oxygen partial pressure of submerged animals progressive decreases during warming, while it remains low but constant during emersion. Our results demonstrate the ability of a bimodal breathing ectotherm to extend its thermal tolerance during air-breathing, suggesting that there are temperature-related physiological benefits during the evolution of the bimodal life style
Taxonomy and pathology of Togninia (Diaporthales) and its Phaeoacremonium anamorphs.
The genus Togninia (Diaporthales, Togniniaceae) is here monographed along with its Phaeoacremonium (Pm.) anamorphs. Ten species of Togninia and 22 species of Phaeoacremonium are treated. Several new species of Togninia (T.) are described, namely T. argentinensis (anamorph Pm. argentinense), T. austroafricana (anamorph Pm. austroafricanum), T. krajdenii, T. parasitica, T. rubrigena and T. viticola. New species of Phaeoacremonium include Pm. novae-zealandiae (teleomorph T. novae-zealandiae), Pm. iranianum, Pm. sphinctrophorum and Pm. theobromatis. Species can be identified based on their cultural and morphological characters, supported by DNA data derived from partial sequences of the actin and Ă-tubulin genes. Phylogenies of the SSU and LSU rRNA genes were used to determine whether Togninia has more affinity with the Calosphaeriales or the Diaporthales. The results confirmed that Togninia had a higher affinity to the Diaporthales than the Calosphaeriales. Examination of type specimens revealed that T. cornicola, T. vasculosa, T. rhododendri, T. minima var. timidula and T. villosa, were not members of Togninia. The new combinations Calosphaeria cornicola, Calosphaeria rhododendri, Calosphaeria transversa, Calosphaeria tumidula, Calosphaeria vasculosa and Jattaea villosa are proposed. Species of Phaeoacremonium are known vascular plant pathogens causing wilting and dieback of woody plants. The most prominent diseases in which they are involved are Petri disease and esca, which occur on grapevines and are caused by a complex of fungi, often including multiple species of Phaeoacremonium. Various Phaeoacremonium species are opportunistic fungi on humans and cause phaeohyphomycosis. The correct and rapid identification of Phaeoacremonium species is important to facilitate the understanding of their involvement in plant as well as human disease. A rapid identification method was developed for the 22 species of Phaeacremonium. It involved the use of 23 species-specific primers, including 20 primers targeting the Ă-tubulin gene and three targeting the actin gene. These primers can be used in 14 multiplex reactions. Additionally, a multiple-entry electronic key based on morphological, cultural and Ă-tubulin sequence data was developed to facilitate phenotypic and sequence-based species identification of the different Phaeoacremonium species. Separate dichotomous keys are provided for the identification of the Togninia and Phaeoacremonium species. Keys for the identification of Phaeoacremonium-like fungi and the genera related to Togninia are also provided. The mating strategy of several Togninia species was investigated with ascospores obtained from fertile perithecia produced in vitro. Togninia argentinensis and T. novae-zealandiae have homothallic mating systems, whereas T. austroafricana, T. krajdenii, T. minima, T. parasitica, T. rubrigena and T. viticola were heterothallic.
Improved heat tolerance in air drives the recurrent evolution of air-breathing
The transition to air-breathing by formerly aquatic species has occurred repeat-edly and independently in fish, crabs and other animal phyla, but the proximatedrivers of this key innovation remain a long-standing puzzle in evolutio-nary biology. Most studies attribute the onset of air-breathing to the repeatedoccurrence of aquatic hypoxia; however, this hypothesis leaves the current geo-graphical distribution of the 300 genera of air-breathing crabs unexplained.Here, we show that their occurrence is mainly related to high environmentaltemperatures in the tropics. We also demonstrate in an amphibious crab thatthe reduced cost of oxygen supply in air extends aerobic performance tohigher temperatures and thus widensthe animalâsthermal niche. These findingssuggest that high water temperature as a driverconsistentlyexplainsthe numer-ous times air-breathing has evolved. The data also indicate a central role foroxygen- and capacity-limited thermal tolerance not only in shaping sensitivityto current climate change but also in underpinning the climate-dependentevolution of animals, in this case the evolution of air-breathing
The Water Uptake of Plasticized Poly(vinyl chloride) SolidâContact CalciumâSelective Electrodes
A hyphenated method based on FTIRâATR and electrochemical impedance spectroscopy has been applied to simultaneously measure the water uptake, changes in the bulk resistance and potential of plasticized poly(vinyl chloride) (PVC) based Ca 2+ âselective coatedâwire (CaCWE) and solidâcontact electrodes (CaSCISEs). Most of the water uptake of the ionâselective membranes (ISMs) used in both electrode types took place within the first 9â
h in 10 â3 â
M CaCl 2 showing good correlation with the stabilization of the individual electrode potentials. The bulk resistance of the ISMs of the CaCWEs and the CaSCISEs with poly(3âoctylthiophene) (POT) as the solidâcontact (SC) increased most during the first 18â
h in 10 â3 â
M CaCl 2 . The increase in the resistance was found to be related to the exchange of K + for Ca 2+ in the ISM and the formation of the Ca 2+ âionophore (ETH 5234) complex having a lower diffusivity than the free K + ions. In contrary to previously published results on silicone rubber based SCISEs and poly(methyl methacrylate):poly( n âdecyl methacrylate) membranes containing POT, the plasticized PVCâbased CaSCISEs with POT as the SC had a higher water uptake than the CaCWEs. The CaSCISEs had a detection limit of 2Ă10 â8 â
M Ca 2+ and a good potential reproducibility of 148.9±1.0â
mV in 10 â4 â
M CaCl 2 .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86920/1/2156_ftp.pd
Record, Relate, Remember: Narrative Constructions of Memory and Generation in Antiquity and the Middle Ages
Die zentralen Funktionen des Erfahrens, ErzĂ€hlens und Erinnerns in der Konstruktion und Ăberlieferung von persönlich-individuellen sowie sozial-kollektiven IdentitĂ€ten haben in den vergangenen Jahren zunehmend Beachtung gefunden. Insbesondere das VerhĂ€ltnis zwischen Text, Kontext und historisch-literarischem Diskurs bietet fortwĂ€hrend Anlass zum interdisziplinĂ€ren Dialog. Die narrativen Prozesse der Generationen- und GedĂ€chtnisbildung in vormodernen Gesellschaften nehmen einen zentralen Stellenwert in Fragestellungen der modernen Geschichts- und Literaturwissenschaft, der Philosophie, der Philologien sowie der historische Anthropologie und Sozialwissenschaft ein. Die soziale Dimension des generationellen GedĂ€chtnisses und das fundierende Potential von generationsĂŒberspannenden ErzĂ€hlungen in der Ausbildung sozialer Gemeinschaften ist heute ein Kernthema der Cultural Memory Studies. Die vom 2.-4. MĂ€rz 2011 in Bamberg abgehaltene internationale Nachwuchstagung bot Raum und Anlass fĂŒr einen theoretischen sowie praxisorientierten Austausch zwischen jungen wie etablierten WissenschaftlerInnen zum Thema der narrativen Konstruktion von GedĂ€chtnis und Generation in Antike und Mittelalter. Der vorliegende Band vereint eine Auswahl der in diesem Rahmen prĂ€sentierten KonferenzvortrĂ€ge. Er möchte gleichsam als Anregung und Wegbereiter fĂŒr zukĂŒnftige Forschungen und GesprĂ€che dienen, die sich dieser wichtigen Themenstellung widmen mögen.Over the last few years, much attention has been devoted to the crucial functions of recording, relating and remembering in the construction of, and customs associated with, personal and collective identities. The resulting interdisciplinary dialogue has paid much attention to the relationship between text, context and historical and literary discourse. Indeed, the narrative processes which often underpin the construction of generational communities and memories in pre-modern societies represent a key element in current trends of interdisciplinary research, comprising the academic disciplines of History, Literary Studies, Philosophy, Philology, Historical Anthropology and the Social Sciences. The social capacities of generational memory, along with the creative potential of transgenerational narratives in the development of social communities, form a key topic in the burgeoning field of Cultural Memory Studies. From 2-4 March 2011, an international and interdisciplinary conference was organised at the University of Bamberg aimed at bringing together researchers from all career stages to engage in a collaborative dialogue on the narrative construction of generation and memory in Antiquity and the Middle Ages. The present volume comprises a selection of papers delivered at that conference. It seeks to provide insight and guidance for future research projects conducted in this field, and thus to encourage scholars to engage with this important topic in their research
International consensus on the management of metastatic gastric cancer:step by step in the foggy landscape: Bertinoro Workshop, November 2022
Background: Many gastric cancer patients in Western countries are diagnosed as metastatic with a median overall survival of less than twelve months using standard chemotherapy. Innovative treatments, like targeted therapy or immunotherapy, have recently proved to ameliorate prognosis, but a general agreement on managing oligometastatic disease has yet to be achieved. An international multi-disciplinary workshop was held in Bertinoro, Italy, in November 2022 to verify whether achieving a consensus on at least some topics was possible. Methods: A two-round Delphi process was carried out, where participants were asked to answer 32 multiple-choice questions about CT, laparoscopic staging and biomarkers, systemic treatment for different localization, role and indication of palliative care. Consensus was established with at least a 67% agreement. Results: The assembly agreed to define oligometastases as a âdynamicâ disease which either regresses or remains stable in response to systemic treatment. In addition, the definition of oligometastases was restricted to the following sites: para-aortic nodal stations, liver, lung, and peritoneum, excluding bones. In detail, the following conditions should be considered as oligometastases: involvement of para-aortic stations, in particular 16a2 or 16b1; up to three technically resectable liver metastases; three unilateral or two bilateral lung metastases; peritoneal carcinomatosis with PCI †6. No consensus was achieved on how to classify positive cytology, which was considered as oligometastatic by 55% of participants only if converted to negative after chemotherapy. Conclusion: As assessed at the time of diagnosis, surgical treatment of oligometastases should aim at R0 curativity on the entire disease volume, including both the primary tumor and its metastases. Conversion surgery was defined as surgery on the residual volume of disease, which was initially not resectable for technical and/or oncological reasons but nevertheless responded to first-line treatment.</p
- âŠ