scholarly journals Glacial to Holocene Paleoceanographic and Continental Paleoclimate Reconstructions Based on ODP Site 1233/GeoB 3313 Off Southern Chile

Author(s):  
Frank Lamy ◽  
Jérome Kaiser
2014 ◽  
Vol 515 ◽  
pp. 83-95 ◽  
Author(s):  
P Pino-Pinuer ◽  
R Escribano ◽  
P Hidalgo ◽  
R Riquelme-Bugueño ◽  
W Schneider

10.3133/pp858 ◽  
1976 ◽  
Author(s):  
Raymond Charles Douglass ◽  
Merlynd Keith Nestell

Zootaxa ◽  
2020 ◽  
Vol 4852 (3) ◽  
pp. 383-395
Author(s):  
RODRIGO PONCE DE LEÓN ◽  
ERICH H. RUDOLPH ◽  
ODILE VOLONTERIO

To date, only one species of Temnocephala is known from Chile, Temnocephala chilensis, and three from southern Argentina (Patagonia), namely T. chilensis, Temnocephala dionii, and Temnocephala mexicana. Here we describe a new species of Temnocephala and provide an updated description of T. chilensis based on material found on an anomuran crab (Aeglidae) from southern Chile. Additional hosts and localities are reported for both species in southern Argentina and Chile, and a diagnostic key for all species of Temnocephala hosted on Aegla and Parastacidae is included as well. In southern Chile, both T. chilensis and the new species were found on the crayfish Samastacus spinifrons and on the anomuran crabs Aegla abtao and Aegla alacalufi; in addition, the new species was found on Aegla manni, and T. chilensis on Aegla rostrata. In southern Argentina, T. chilensis and the new species were found on Aegla riolimayana and S. spinifrons. Based on their shared traits (morphology of the penial stylet, host preferences and geographic distribution), the temnocephalans hosted in Aegla are tentatively gathered into two clusters, the Chilensis and Axenos groups. 


1992 ◽  
Vol 38 (128) ◽  
pp. 208-209 ◽  
Author(s):  
Stephan Harrison
Keyword(s):  

Author(s):  
L.E. Delgado ◽  
R. De Ríos ◽  
M. Perevochtchikova ◽  
I.A. Marín ◽  
R. Fuster ◽  
...  

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1105
Author(s):  
Fernanda Erpel ◽  
María Salomé Mariotti-Celis ◽  
Javier Parada ◽  
Franco Pedreschi ◽  
José Ricardo Pérez-Correa

Brown seaweed phlorotannins have shown the potential to promote several health benefits. Durvillaea incurvata and Lessonia spicata—species that are widely distributed in central and southern Chile—were investigated to obtain phlorotannin extracts with antioxidant and antihyperglycemic potential. The use of an environmentally friendly and food-grade glycerol-based pressurized hot liquid extraction (PHLE) process (15% v/v glycerol water) was assessed for the first time to obtain phlorotannins. Multiple effects were analyzed, including the effect of the species, harvesting area (Las Cruces and Niebla), and anatomical part (holdfast, stipe, and frond) on the extracts’ polyphenol content (TPC), antioxidant capacity (AC), and carbohydrate-hydrolyzing enzyme—α-glucosidase and α-amylase—inhibitory activity. Contaminants, such as mannitol, heavy metals (As, Cd, Pb, Hg, and Sn), and 5-hydroxymethylfurfural (HMF), were also determined. The anatomical part used demonstrated a significant impact on the extracts’ TPC and AC, with holdfasts showing the highest values (TPC: 95 ± 24 mg phloroglucinol equivalents/g dry extract; DPPH: 400 ± 140 μmol Trolox equivalents/g dry extract; ORAC: 560 ± 130 μmol TE/g dry extract). Accordingly, holdfast extracts presented the most potent α-glucosidase inhibition, with D. incurvata from Niebla showing an activity equivalent to fifteen times that of acarbose. Only one frond and stipe extract showed significant α-glucosidase inhibitory capacity. No α-amylase inhibition was found in any extract. Although no HMF was detected, potentially hazardous cadmium levels (over the French limit) and substantial mannitol concentrations—reaching up to 50% of the extract dry weight—were found in most seaweed samples and extracts. Therefore, further purification steps are suggested if food or pharmaceutical applications are intended for the seaweed PHLE extracts obtained in this study.


2021 ◽  
Vol 13 (15) ◽  
pp. 8414
Author(s):  
Martín Bascopé ◽  
Kristina Reiss

This article analyzes STEM projects conducted in eight schools with children from 4 to 10 years old in southern Chile. The main purpose of the study was to describe and analyze how these projects can affect students’ and educators’ attitudes and create community capacities to tackle local socioecological challenges. We used an ethnographic design with an intentioned coding process of interviews and participant observations to summarize one year of collaborative and transdisciplinary project building. The results describe the main attitudinal changes of teachers and students and give evidence on how these projects create new links and foster collaborations with local actors and organizations that are usually sidelined from educational experiences. Examples of meaningful learning experiences to tackle sustainability challenges were systematized and shared, to inspire new initiatives, raise new voices, and promote active participation of the new generations to foster socioecological resilience.


2021 ◽  
Author(s):  
Bruk Lemma ◽  
Lucas Bittner ◽  
Bruno Glaser ◽  
Seifu Kebede ◽  
Sileshi Nemomissa ◽  
...  

AbstractThe hydrogen isotopic composition of leaf wax–derived n-alkane (δ2Hn-alkane) and oxygen isotopic composition of hemicellulose–derived sugar (δ18Osugar) biomarkers are valuable proxies for paleoclimate reconstructions. Here, we present a calibration study along the Bale Mountains in Ethiopia to evaluate how accurately and precisely the isotopic composition of precipitation is imprinted in these biomarkers. n-Alkanes and sugars were extracted from the leaf and topsoil samples and compound–specific δ2Hn-alkane and δ18Osugar values were measured using a gas chromatograph–thermal conversion–isotope ratio mass spectrometer (GC–TC–IRMS). The weighted mean δ2Hn-alkane and δ18Osugar values range from − 186 to − 89‰ and from + 27 to + 46‰, respectively. Degradation and root inputs did not appear to alter the isotopic composition of the biomarkers in the soil samples analyzed. Yet, the δ2Hn-alkane values show a statistically significant species dependence and δ18Osugar yielded the same species–dependent trends. The reconstructed leaf water of Erica arborea and Erica trimera is 2H– and 18O–enriched by + 55 ± 5 and + 9 ± 1‰, respectively, compared to precipitation. By contrast, Festuca abyssinica reveals the most negative δ2Hn-alkane and least positive δ18Osugar values. This can be attributed to “signal–dampening” caused by basal grass leaf growth. The intermediate values for Alchemilla haumannii and Helichrysum splendidum can be likely explained with plant physiological differences or microclimatic conditions affecting relative humidity (RH) and thus RH–dependent leaf water isotope enrichment. While the actual RH values range from 69 to 82% (x̄ = 80 ± 3.4%), the reconstructed RH values based on a recently suggested coupled δ2Hn-alkane –δ18Osugar (paleo–) hygrometer approach yielded a mean of 78 ± 21%. Our findings corroborate (i) that vegetation changes, particularly in terms of grass versus non–grassy vegetation, need to be considered in paleoclimate studies based on δ2Hn-alkane and δ18Osugar records and (ii) that the coupled δ2Hn-alkane –δ18Osugar (paleo–) hygrometer approach holds great potential for deriving additional paleoclimatic information compared to single isotope approaches.


2019 ◽  
Vol 23 (2) ◽  
pp. 102-110 ◽  
Author(s):  
Mónica Pavez ◽  
Claudia Troncoso ◽  
Irma Osses ◽  
Rodrigo Salazar ◽  
Vijna Illesca ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document