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2021 ◽  
Author(s):  
Alexander H. Mason ◽  
Alessandro Motta ◽  
Anusheela Das ◽  
Qing Ma ◽  
Michael J. Bedzyk ◽  
...  

Polyolefins comprise a major fraction of single-use plastics and yet their catalytic deconstruction/recycling has proven challenging due to their inert hydrocarbon connectivities. Here an electrophilic earth-abundant single-site organozirconium catalyst chemisorbed on a highly Brønsted acidic support and characterized by a broad array of experimental and theoretical techniques, is shown to mediate the rapid hydrogenolytic cleavage of molecular and macromolecular saturated hydrocarbons under mild conditions. For n-hexadecane, hydrogenolysis to light hydrocarbons proceeds with an activity of 690 mol n-hexadecane · mol Zr-1 · h-1 at 150°C/2.5 atm H2 pressure. Under similar solventless conditions, polyethylene, polyethylene-co- 1-octene, isotactic polypropylene, and a post-consumer sandwich bag are rapidly hydrogenolyzed to low molecular mass hydrocarbons via a turnover-limiting C-C scission pathway involving ßalkyl transfer rather than more common σ-bond metathesis.


Genealogy ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 77
Author(s):  
Josep Maria Oller ◽  
Albert Satorra ◽  
Adolf Tobeña

Amid the tensions created by the secession push in Catalonia (Spain), an important conflicting issue has been the “immersion linguistic educational system”, in which the Catalan language has precedence throughout all of the primary and secondary school curricula. Here, we present an analysis of a survey (n = 1002) addressing features of linguistic and political opinion profiles with reference to the mother language and feelings of national identity. The results show that the mother language is a factor that differentiated the participants in terms of common linguistic uses and opinions about the “immersion educational system”. These results were confirmed when segmenting respondents via their feelings of national self-identification. The most distinctive political opinions consisted of either asserting or denying the damage to social harmony produced by the secession campaign. Overall, the findings show that a major fraction of the Catalonian citizenry is subjected to an education system that does not meet their linguistic preferences. We discuss these findings, connecting them to an ethnolinguistic divide based mainly on mother language (Catalan vs. Spanish) and family origin—a complex frontier that has become the main factor determining alignment during the ongoing political conflict.


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1513
Author(s):  
Zhentao Zhang ◽  
Jesse Villalpando ◽  
Wenhui Zhang ◽  
Young-Jae Nam

Forced expression of core cardiogenic transcription factors can directly reprogram fibroblasts to induced cardiomyocyte-like cells (iCMs) in vitro and in vivo. This cardiac reprogramming approach provides a proof of concept for induced heart regeneration by converting a fibroblast fate to a cardiomyocyte fate. However, it remains elusive whether chamber-specific cardiomyocytes can be generated by cardiac reprogramming. Therefore, we assessed the ability of the cardiac reprogramming approach for chamber specification in vitro and in vivo. We found that in vivo cardiac reprogramming post-myocardial infarction exclusively induces a ventricular-like phenotype, while a major fraction of iCMs generated in vitro failed to determine their chamber identities. Our results suggest that in vivo cardiac reprogramming may have an inherent advantage of generating chamber-matched new cardiomyocytes as a potential heart regenerative approach.


Author(s):  
N. V. Samokhvalova ◽  
A. V. Kruchonok ◽  
B. Yu. Anoshenko ◽  
V. V. Titok

An analysis of genetic heterogeneity was performed for two populations of Ophrys insectifera L. located in the Berezinsky Biosphere Reserve and the Verkudy village. The species are critically endangered (CR). The analysis of data obtained using iPBS markers detected the higher risk of extinction of the population in the Berezinsky Biosphere Reserve than the population from the Verkudy village, since the level of population genetic heterogeneity from the Verkudy is higher compared to the Berezinsky Biosphere Reserve. Molecular variance analysis (AMOVA) and other parameters of genetic variation showed the major fraction of intrapopulation variation (64 %, Gst = 0.26). Principal Coordinates Analysis (PCoA) revealed two groups that coincided with natural populations, and confirmed a larger genetic heterogeneity in the population from the Verkudy.


Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1002
Author(s):  
Nerijus Nika ◽  
Mindaugas Zilius ◽  
Tomas Ruginis ◽  
Gianmarco Giordani ◽  
Kasparas Bagdonas ◽  
...  

Lampreys spend their larval stage within fine sand fluvial sediments, where they burrow and act as filter feeders. Lamprey larvae (ammocoetes) can significantly affect benthic-pelagic coupling and nutrient cycling in rivers, due to high densities. However, their bioturbation, feeding and excretion activities are still poorly explored. These aspects were investigated by means of laboratory incubations of intact sediments added with ammocoetes and of animals alone. Oxygen respiration, nutrient fluxes and excretion rates were determined. Individual ammocoete incubations suggested that biomass-specific oxygen consumption and ammonium, reactive phosphorus and silica excretion were size-dependent, and greater in small compared to large individuals. The comparison of ammocoetes metabolic rates with rates measured in intact sediments revealed that ammocoetes activity decreases significantly when they are burrowed in sediments. Furthermore, results suggest that a major fraction of ammonium excreted by ammocoetes was assimilated by benthic microbes or microalgae to overcome in situ N-limitation. Alternatively, part of the excreted ammonium was oxidized and denitrified within sediments, as nitrate uptake rather increased along with ammocoetes density. Ammocoetes excreted reactive phosphorus and silica but such production was not apparent in bioturbated sediments, likely due to microbial or microalgal uptake or to immobilization in sediments.


Plants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 601
Author(s):  
Jesús Palá-Paúl ◽  
Lachlan M. Copeland ◽  
Joseph J. Brophy

Trachymene incisa subsp. incisa is an Australian endemic taxon that varies greatly in the abundance and length of the leaf trichomes. The essential oil composition of five populations of this subspecies, three corresponding to the typical glabrous form and two of the particularly hairy variant, has been analyzed in an attempt to determinate if that variability is also reflected in their composition. The oils have been extracted by hydrodistillation and analyzed by Gas Chromatography (GC) and Gas Chromatography coupled to Mass Spectrometry (GC–MS). The essential oils of T. incisa subsp. incisa were characterized by the high amount of sesquiterpenes that were the major fraction. The sesquiterepene hydrocarbons were significantly higher in the hairy variant in comparison to the glabrous one. According to the main compound, three different chemotypes were found: I.—β-selinene + bicyclogermacrene and II.—γ-bisabolene + α-pinene for the typical glabrous variant and III.—bicyclogermacrene + β-caryophyllene for the hairy variant.


Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 362
Author(s):  
Mohammadreza Sadeghi ◽  
Yuji Tomaru ◽  
Tero Ahola

Increasing sequence information indicates that RNA viruses constitute a major fraction of marine virus assemblages. However, only 12 RNA virus species have been described, infecting known host species of marine single-celled eukaryotes. Eight of these use diatoms as hosts, while four are resident in dinoflagellate, raphidophyte, thraustochytrid, or prasinophyte species. Most of these belong to the order Picornavirales, while two are divergent and fall into the families Alvernaviridae and Reoviridae. However, a very recent study has suggested that there is extraordinary diversity in aquatic RNA viromes, describing thousands of viruses, many of which likely use protist hosts. Thus, RNA viruses are expected to play a major ecological role for marine unicellular eukaryotic hosts. In this review, we describe in detail what has to date been discovered concerning viruses with RNA genomes that infect aquatic unicellular eukaryotes.


Author(s):  
Jesús Palá-Paúl ◽  
Lachlan M. Copeland ◽  
Joseph J. Brophy

Trachymene incisa subsp. incisa is an Australian endemic taxon that varies greatly in the abundance and length of the leaf trichomes. The essential oil composition of five populations of this subspecies, three corresponding to the typical glabrous form and two of the particularly hairy variant, has been analyzed in an attempt to determinate if that variability is also reflected in their composition. The oils have been extracted by hydrodistillation and analysed by Gas Chromatography (GC) and Gas Chromatography coupled to Mass Spectrometry (GC-MS). The essential oils of T. incisa subsp. incisa were characterized by the high amount of sesquiterpenes that were the major fraction. The sesquiterepene hydrocarbons were significantly higher in the hairy variant in comparison to the glabrous one. According to the main compound three different chemotypes were found: I.- -selinene + bicyclogermacrene and II.- -bisabolene + -pinene for the typical glabrous variant and III.- bicyclogermacrene + -caryophyllene for the hairy variant.


2021 ◽  
Vol 12 (1) ◽  
pp. 734-741
Author(s):  
Aneena Suresh ◽  
Oorvashree S ◽  
Jayalakshmi T ◽  
Ramyaa R S ◽  
Ngawang Choedon

This study was conducted to ascertain the knowledge and practices related to biomedical waste management in secondary care hospitals in our region. The required information was obtained using a simple questionnaire which included 2 parts, namely, knowledge and practices with 16 and 20 questions respectively. Out of the 80 respondents, 75 % were females. Nurses constituted a major fraction of healthcare professionals (70%) in hospitals. About 47.5% of the respondents had a working experience of 0-5 years. Females had better knowledge and practices in the disposal of medical wastes (91.14% and 94.998%) as compared to males (88.125% and 89%). There was a significant association of age with the knowledge (p= 0.013) and insignificant regarding practice (p= 0.998) of healthcare professionals. The knowledge and practices of all healthcare professionals were overall good. There was a significant association between a professional category of healthcare professionals with knowledge (p= 0.00000181) and practices (p= 0.003129) of medical waste disposal. The results of the investigation uncovered that healthcare professionals had great learning about the disposal of biomedical waste. It was additionally discovered that healthcare professionals adhered to the strategies and the rules related to biomedical waste management.


2021 ◽  
Author(s):  
Zhentao Zhang ◽  
Jesse Villalpando ◽  
Wenhui Zhang ◽  
Young-Jae Nam

Abstract Forced expression of core cardiogenic transcription factors can directly reprogram fibroblasts to induced cardiomyocyte-like cells (iCMs) in vitro and in vivo. This cardiac reprogramming approach provides a proof of concept for induced heart regeneration by converting a fibroblast fate to a cardiomyocyte fate. However, it remains elusive whether chamber-specific cardiomyocytes can be generated by cardiac reprogramming. Therefore, we assessed the ability of the cardiac reprogramming approach for chamber specification in vitro and in vivo. We found that in vivo cardiac reprogramming post-myocardial infarction exclusively generates ventricular-like iCMs, while a major fraction of iCMs generated in vitro fail to determine their chamber identities. Our results indicate that in vivo cardiac reprogramming may have an inherent advantage of generating chamber-matched new cardiomyocytes as a potential heart regenerative approach.


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