Fire, vegetation, and Holocene climate in a southeastern Tibetan lake: A multi-biomarker reconstruction from Paru Co

The fire history of the Tibetan Plateau over centennial to millennial timescales is not well known. Recent ice core studies reconstruct fire history over the past few decades but do not extend through the Holocene. Lacustrine sedimentary cores, however, can provide continuous records of local environmental change on millennial scales during the Holocene through the accumulation and preservation of specific organic molecular biomarkers. To reconstruct Holocene fire events and vegetation changes occurring on the southeastern Tibetan Plateau and the surrounding areas, we used a multi-proxy approach, investigating multiple biomarkers preserved in core sediment samples retrieved from Paru Co, a small lake located in the Nyainqentanglha Mountains (29°47045.600N, 92°21007.200 E; 4845ma.s.l.). Biomarkers include n-alkanes as indicators of vegetation, polycyclic aromatic hydrocarbons (PAHs) as combustion proxies, fecal sterols and stanols (FeSts) as indicators of the presence of humans or grazing animals, and finally monosaccharide anhydrides (MAs) as specific markers of vegetation burning processes. Insolation changes and the associated influence on the Indian summer monsoon (ISM) affect the vegetation distribution and fire types recorded in Paru Co throughout the Holocene. The early Holocene (10.7- 7.5 cal kyr BP) n-alkane ratios demonstrate oscillations between grass and conifer communities, resulting in respective smouldering fires represented by levoglucosan peaks, and high-temperature fires represented by high-molecular-weight PAHs. Forest cover increases with a strengthened ISM, where coincident high levoglucosan to mannosan (L = M) ratios are consistent with conifer burning. The decrease in the ISM at 4.2 cal kyr BP corresponds with the expansion of regional civilizations, although the lack of human FeSts above the method detection limits excludes local anthropogenic influence on fire and vegetation changes. The late Holocene is characterized by a relatively shallow lake surrounded by grassland, where all biomarkers other than PAHs display only minor variations. The sum of PAHs steadily increases throughout the late Holocene, suggesting a net increase in local to regional combustion that is separate from vegetation and climate change

Design and development of a coaxial cryogenic probe for precision measurements of the quantum hall effect in the ac regime

The quantum Hall effect is the basis for the realisation of the resistance and impedance units in the International System of units since 2019. This paper describes a cryogenic probe that allows to set graphene Hall devices in quantisation conditions in a helium bath (4.2 K) and magnetic fields up to 6 T, to perform precision measurements in the AC regime with impedance bridges. The probe has a full coaxial wiring, isolated from the probe structure, and holds the device in a TO-8 socket. First, characterization experiments are reported on a GaAs device, showing quantisation at 5.5 T. In the AC regime, multiple-series connections will be employed to minimize the residual error, quantified by electrical modelling of the probe

Integrative genomic analysis reveals distinct transcriptional and genetic features associated with chromosome 13 deletion in multiple myeloma

Background and Objectives The chromosome 13 deletion (Delta(13)) is one of the most frequent chromosomal alterations in multiple myeloma (MM). Delta(13) is associated with an unfavorable prognosis, although there is increasing agreement that its prognostic relevance must be related to the ploidy status and the presence of different chromosomal translocations. The aim of this study was to provide a comprehensive analysis of the transcriptional features of Delta(13) in MM.Design and Methods Highly purified plasma cells from 80 newly diagnosed MM patients were characterized by means of fluorescence in situ hybridization (FISH) and high-density oligonucleotide microarray for gene expression profiling and chromosomal alterations.Results We identified 67 differentially expressed genes in the patients with and without the chromosome 13 deletion, all of which were downregulated in the cases with Delta(13): 44 mapped along the whole chromosome 13, seven on chromosome 11 and three on chromosome 19. Functional analyses of the selected genes indicated their involvement in protein biosynthesis, ubiquitination and transcriptional regulation. An integrative genomic approach based on regional analyses of the gene expression data identified distinct chromosomal regions whose global expression modulation could differentiate Delta(13)-positive cases, in particular the upregulation of 1q21-1q42 and the downregulation of 19p and almost the entire chromosome 11. FISH analyses confirmed the close relationship between Delta(13)-positivity and the presence of extra copies of 1q21-1q42 (p=6x10(-4)) or the absence of chromosome 11 and 19 trisomy (p=5x10(-4)).Interpretation and Conclusions Our results indicate that distinct types of chromosomal aberrations are closely related to the transcriptional profiles of Delta(13)-positive cases, suggesting that the contribution of Delta(13) to the malignancy should be considered together with associated abnormalities

Strategies for the delay of surgery in the management of resectable hepatobiliary malignancies during the COVID-19 pandemic

Objective: We aimed to review data about delaying strategies for the management of hepatobiliary cancers requiring surgery during the covid-19 pandemic. Background: Given the covid-19 pandemic, many jurisdictions, to spare resources, have limited access to operating rooms for elective surgical activity, including cancer, thus forcing deferral or cancellation of cancer surgeries. Surgery for hepatobiliary cancer is high-risk and particularly resource-intensive. Surgeons must critically appraise which patients will benefit most from surgery and which ones have other therapeutic options to delay surgery. Little guidance is currently available about potential delaying strategies for hepatobiliary cancers when surgery is not possible. Methods: An international multidisciplinary panel reviewed the available literature to summarize data relating to standard-of-care surgical management and possible mitigating strategies to be used as a bridge to surgery for colorectal liver metastases, hepatocellular carcinoma, gallbladder cancer, intrahepatic cholangiocarcinoma, and hilar cholangiocarcinoma. Results: Outcomes of surgery during the covid-19 pandemic are reviewed. Resource requirements are summarized, including logistics and adverse effects profiles for hepatectomy and delaying strategies using systemic, percutaneous and radiation ablative, and liver embolic therapies. For each cancer type, the long-term oncologic outcomes of hepatectomy and the clinical tools that can be used to prognosticate for individual patients are detailed. Conclusions: There are a variety of delaying strategies to consider if availability of operating rooms decreases. This review summarizes available data to provide guidance about possible delaying strategies depending on patient, resource, institution, and systems factors. Multidisciplinary team discussions should be leveraged to consider patient- and tumour-specific information for each individual case.publishedVersio

Un laboratorio di taratura e verifica dei contatori elettrici anche in condizioni di scarsa Power Quality

La misura accurata dell’energia elettrica `e determinante, oltre che per un’equa tariffazione, anche per garantire l’osservabilit`a della rete elettrica. Nella transizione verso il concetto di smart grid, la diffusione della microgenerazione e di carichi non lineari ha peggiorato i parametri di power quality della rete. La misura delle corrispondenti forme d’onda di tensione e corrente, non pi`u sinusoidali, pu`o non avere una riferibilit`a adeguata

CSF levels of glutamine synthetase and GFAP to explore astrocytic damage in seronegative NMOSD

OBJECTIVE: To explore levels of astrocytopathy in neuromyelitis optica spectrum disorder (NMOSD) by measuring levels of the astrocytic enzyme glutamine synthetase (GS) and glial fibrillary acidic protein (GFAP), an established astrocytic biomarker known to be associated with disease activity in multiple sclerosis. METHODS: Cerebrospinal fluid concentrations of GS and GFAP were measured by ELISA in patients with NMOSD (n=39, 28 aquaporin-4 (AQP4)-Ab-seropositive, 3 double-Ab-seronegative, 4 myelin oligodendrocyte glycoprotein (MOG)-Ab-seropositive and 4 AQP4-Ab-seronegative with unknown MOG-Ab-serostatus), multiple sclerosis (MS) (n=69), optic neuritis (n=5) and non-neurological controls (n=37). RESULTS: GFAP and GS concentrations differed significantly across groups (both p<0.001), showing a similar pattern of elevation in patients with AQP4-Ab-seropositive NMOSD. GS and GFAP were significantly correlated, particularly in patients with AQP4-Ab-seropositive NMOSD (rs=0.70, p<0.001). Interestingly, GFAP levels in some patients with double-Ab-seronegative NMOSD were markedly increased. CONCLUSIONS: Our data indicate astrocytic injury occurs in some patients with double-Ab-seronegative NMOSD, which hints at the possible existence of yet undiscovered astrocytic autoimmune targets. We hypothesise that elevated GS and GFAP levels could identify those double-Ab-seronegative patients suitable to undergo in-depth autoimmune screening for astrocytic antibodies