A new set-up for simultaneous high-precision measurements of CO₂,δ¹³C-CO₂ and δ¹⁸O-CO2 on small ice core samples

Palaeoatmospheric records of carbon dioxide and its stable carbon isotope composition (<i>δ</i>¹³C) obtained from polar ice cores provide important constraints on the natural variability of the carbon cycle. However, the measurements are both analytically challenging and time-consuming; thus only data exist from a limited number of sampling sites and time periods. Additional analytical resources with high analytical precision and throughput are thus desirable to extend the existing datasets. Moreover, consistent measurements derived by independent laboratories and a variety of analytical systems help to further increase confidence in the global CO₂ palaeo-reconstructions. Here, we describe our new set-up for simultaneous measurements of atmospheric CO₂ mixing ratios and atmospheric <i>δ</i>¹³C and <i>δ</i>¹⁸O-CO₂ in air extracted from ice core samples. The centrepiece of the system is a newly designed needle cracker for the mechanical release of air entrapped in ice core samples of 8–13 g operated at −45 °C. The small sample size allows for high resolution and replicate sampling schemes. In our method, CO₂ is cryogenically and chromatographically separated from the bulk air and its isotopic composition subsequently determined by continuous flow isotope ratio mass spectrometry (IRMS). In combination with thermal conductivity measurement of the bulk air, the CO₂ mixing ratio is calculated. The analytical precision determined from standard air sample measurements over ice is ±1.9 ppm for CO₂ and ±0.09 ‰ for <i>δ</i>¹³C. In a laboratory intercomparison study with CSIRO (Aspendale, Australia), good agreement between CO₂ and <i>δ</i>¹³C results is found for Law Dome ice core samples. Replicate analysis of these samples resulted in a pooled standard deviation of 2.0 ppm for CO₂ and 0.11 ‰ for <i>δ</i>¹³C. These numbers are good, though they are rather conservative estimates of the overall analytical precision achieved for single ice sample measurements. Facilitated by the small sample requirement, replicate measurements are feasible, allowing the method precision to be improved potentially. Further, new analytical approaches are introduced for the accurate correction of the procedural blank and for a consistent detection of measurement outliers, which is based on <i>δ</i>¹⁸O-CO₂ and the exchange of oxygen between CO₂ and the surrounding ice (H₂O)

First results on the evaluation of the ground-cover biodiversity in an agroforestry poultry system

The first results on the impact of hen grazing on ground cover composition and biodiversity of two hazelnut orchards (sites A and B) in the southern Italy are presented. The selected sites were characterized by different size and environmental conditions that were, respectively for A and B: area, 4 and 5 ha; altitude, 525 and 660 m a.s.l.; annual mean temperature, +12°C and +13°C; annual precipitation: 730 and 780 mm. Besides, ground covers of the sites were different for plant species presence and distribution. In each site three 120 m2 areas were considered, each of which was provided with a mobile coop (5 hens/m2) to house during the night ten 25-week-old commercial egg-laying chickens. The trial started the first decade of May 2019. The use of hen grazing affected quantitatively and qualitatively the herbaceous stratum of the study sites, as the number of taxa composing the ground cover decreased in both sites, whereas the relative frequencies varied (increased or decreased) according to the taxon. By computing different indices of alpha diversity, we observed significant differences in species richness and diversity after hen grazing only in one site. However, the value of the qualitative Sørensen index showed a high overlap in the assemblage of ground cover before and after hen grazing in both sites. By comparing the sites, we found that, at the beginning of the trial, the ground cover of one site was richer and more diverse compared to the other site; however, the reverse situation occurred after hen grazing. Overall, our results indicate that integrating fruit trees with poultry may play a positive role in an agroforestry context, mainly in terms of control of vegetation growth

Increased orexin A concentrations in cerebrospinal fluid of patients with behavioural variant frontotemporal dementia

Orexins are hypothalamic neuropeptides that regulate several physiological functions, such as appetite, arousal, cognition, stress, sleep and metabolism. Emerging pieces of evidence suggest an orexinergic dysfunction in several neuropsychiatric disorders, including depression, anxiety and addiction. A syndromic overlap between behavioural variant frontotemporal dementia (bvFTD) and several psychiatric disorders was recently demonstrated. Therefore, we analysed cerebrospinal fluid (CSF) orexin A concentrations of 40 bvFTD and 32 non-demented patients, correlating neuropeptide concentrations with several clinical characteristics. A significant increase of orexin A concentrations was found in bvFTD patients when compared to controls (p<0.001). CSF orexin A concentration showed a correlation with Mini-Mental State Examination scores, drug assumption, history of compulsive behaviour and extrapyramidal signs. Moreover, we found a relationship between CSF markers of neurodegeneration, total tau and Aβ(1–42) and CSF orexin A concentrations. Our study provides evidence of an orexinergic dysfunction in bvFTD, correlating with several clinical symptoms. Further larger studies are needed to confirm our data. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10072-021-05250-x

Sutureless aortic valve replacement as an alternative treatment for patients belonging to the "gray zone" between transcatheter aortic valve implantation and conventional surgery: A propensity-matched, multicenter analysis

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Time related variations in stem cell harvesting of umbilical cord blood

Umbilical cord blood (UCB) contains hematopoietic stem cells and multipotent mesenchymal cells useful for treatment in malignant/nonmalignant hematologic-immunologic diseases and regenerative medicine. Transplantation outcome is correlated with cord blood volume (CBV), number of total nucleated cells (TNC), CD34+ progenitor cells and colony forming units in UCB donations. Several studies have addressed the role of maternal/neonatal factors associated with the hematopoietic reconstruction potential of UCB, including: gestational age, maternal parity, newborn sex and birth weight, placental weight, labor duration and mode of delivery. Few data exist regarding as to how time influences UCB collection and banking patterns. We retrospectively analyzed 17.936 cord blood donations collected from 1999 to 2011 from Tuscany and Apulia Cord Blood Banks. Results from generalized multivariable linear mixed models showed that CBV, TNC and CD34+ cell were associated with known obstetric and neonatal parameters and showed rhythmic patterns in different time domains and frequency ranges. The present findings confirm that volume, total nucleated cells and stem cells of the UCB donations are hallmarked by rhythmic patterns in different time domains and frequency ranges and suggest that temporal rhythms in addition to known obstetric and neonatal parameters influence CBV, TNC and CD34+ cell content in UBC units

The novel zoonotic COVID-19 pandemic: An expected global health concern

18 years ago, in 2002, the world was astonished by the appearance of Severe Acute Respiratory Syndrome (SARS), supported by a zoonotic coronavirus, called SARS-CoV, from the Guangdong Province of southern China. After about 10 years, in 2012, another similar coronavirus triggered the Middle East Respiratory Syndrome (MERS-CoV) in Saudi Arabia. Both caused severe pneumonia killing 774 and 858 people with 8700 cases of confirmed infection for the former, and 2494 for the latter, causing significant economic losses. 8 years later, despite the MERS outbreak remaining in certain parts of the world, at the end of 2019, a new zoonotic coronavirus (SARS-CoV-2) and responsible of coronavirus Disease (COVID-19), arose from Wuhan, Hubei Province, China. It spread rapidly and to date has killed 3,242 persons with more than 81,000 cases of infection in China and causing over 126,000 global cases and 5,414 deaths in 166 other countries around the world, especially Italy. SARS-CoV-2 would seem to have come from a bat, but the intermediate reservoir continues to be unknown. Nonetheless, as for SARS-CoV and MERS CoV, the Spillover effect linked to animal-human promiscuity, human activities including deforestation, illegal bush-trafficking and bushmeat, cannot be excluded. Recently, however, evidence of inter-human only transmission of SARS-CoV-2 has been accumulated and thus, the outbreak seems to be spreading by human-to-human transmission throughout a large part of the world. Herein we will provide with an update on the main features of COVID-19 and suggest possible solutions how to halt the expansion of this novel pandemic