Mud volcanoes and methane seeps in Romania: main features and gas flux

Romania is one of the European countries with the most vigorous natural seepage of methane, uprising from pressurised natural gas and petroleum reservoirs through deep faults. The largest seepage zone is represented by large mud volcanoes, with CH4 >80% v/v, occurring on the Berca-Arbanasi hydrocarbon-bearing faulted anticline, in the Carpathian Foredeep. Smaller mud volcanoes have been identified in other areas of the Carpathian Foredeep, in the Transylvanian Depression and on the Moldavian Platform. New surveys carried out in Transylvania allowed us to discover the richest N2 mud volcano zone in the world (N2>90% v/v), with a remarkably high He content and a helium isotopic signature which highlights a contribution of mantle-derived source. The large mud volcanoes are generally quiescent, with rare explosive episodes and provide a methane flux in the order of 102-103 t km−2 y−1. Independently from mud volcanism, a remarkable dry macroseepage, however, has been found, with a degassing rate up to three orders of magnitude higher than that of mud volcanoes (i.e. 103-105 t km−2 y−1). The total gas flux from all investigated macroseepage zones in Romania is estimated in the range of 1500-2500 t y−1. The emission from microseepage, pervasively occurring throughout the hydrocarbon-prone basins, has yet to be assessed and added to the total gas output to the atmosphere

Image-based evaluation of seam puckering appearance

2008-2009 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

THE CONFLUENCE RATIO OF THE TRANSYLVANIAN BASIN RIVERS

There are many possibilities to assess the hydrological and geomorphological evolution of a territory. Among them, one remarks the confluence ratio of the rivers belonging to different catchment areas. The values of this indicator may provide information regarding the stage of evolution of the fluvial landforms in the Transylvanian Basin. Also, the values may serve for the calculation of other parameters of catchment areas like: the degree of finishing of the drainage basin for its corresponding order, the density of river segments within a catchment area etc. To calculate the confluence ratio, 35 catchment areas of different orders have been selected. The confluence ratio varies between 3.04 and 6.07. The large range of values demonstrates the existence of a heterogeneous lithology and of morphological and hydrographical contrasts from one catchment area to the other. The existence of values above 5, correlated also with observations in the field, reveals an accelerated dynamics of the geomorphological processes in those catchment areas. This dynamic is mainly supported by the high landform fragmentation due to the first order rivers. In contrast, the catchment areas that have a confluence ratio below 5 are in a more advanced stage of evolution with stable slopes, unable to initiate new first order river segments

LARS-like symptoms in the general population may suggest the significance of postoperative functional problems and emotional implications of rectal surgery

Background & Aim. Sphincter-saving rectal surgery is prone to cause changes in bowel function associated with Low Anterior Resection Syndrome (LARS). Our aim was to assess LARS-like symptoms within a population of 50-80-year old in order to understand the functional disturbances and emotional impact of LARS. Materials and methods: We used a questionnaire to evaluate LARS with the following categories of symptoms: flatulence control, anal incontinence, frequency, clustering and urgency of the stools, and the psycho-emotional impact created by the presence of these symptoms. We calculated the severity of LARS on 343 responders. Results. The average age of the responders (57.4% females) was 60 years. Overall, 48.1% of those questioned had no LARS-associated symptoms, while the rest presented either minor (39.9%) or major (12%) LARS-like symptomatology according to the assessment scale. Women have a higher relative risk (1.32) of having minor or major LARS. The frequency of stools did not correlate with the overall LARS score. The psycho-emotional impact was mostly influenced by the presence of incontinence (p=0.001) and urgency (p=0.05). Discussions. The study highlights the need to integrate the initial status of patients into the overall quantification of the effects of surgery on the quality of life. Age does not influence the prevalence of LARS, but symptoms seem more prevalent in women. The psycho-emotional impact is relevant to the general population, so explanations given during the informed consent and accurate description of potential consequences of surgical intervention increase compliance to ensure better post-operative control of the symptomatology. Conclusions. Deriving a normative LARS-like score may alter the interpretation and discussion of LARS scores for future rectal cancer patients, and it also provides a better understanding of the emotional impact of such symptoms on certain population subsets or cultural groups

An edge-queued datagram service for all datacenter traffic

Modern datacenters support a wide range of protocols and in-network switch enhancements aimed at improving performance. Unfortunately, the resulting protocols often do not coexist gracefully because they inevitably interact via queuing in the network. In this paper we describe EQDS, a new datagram service for datacenters that moves almost all of the queuing out of the core network and into the sending host. This enables it to support multiple (conflicting) higher layer protocols, while only sending packets into the network according to any receiver-driven credit scheme. EQDS can transparently speed up legacy TCP and RDMA stacks, and enables transport protocol evolution, while benefiting from future switch enhancements without needing to modify higher layer stacks. We show through simulation and multiple implementations that EQDS can reduce FCT of legacy TCP by 2x, improve the NVMeOF-RDMA throughput by 30%, and safely run TCP alongside RDMA on the same network

Alzheimer’s disease marker phospho-tau181 is not elevated in the first year after moderate-severe TBI

Background: Traumatic brain injury (TBI) is associated with the tauopathies Alzheimer’s disease and chronic traumatic encephalopathy. Advanced immunoassays show significant elevations in plasma total tau (t-tau) early post-TBI, but concentrations subsequently normalise rapidly. Tau phosphorylated at serine-181 (p-tau181) is a well-validated Alzheimer’s disease marker that could potentially seed progressive neurodegeneration. We tested whether post-traumatic p-tau181 concentrations are elevated and relate to progressive brain atrophy. Methods: Plasma p-tau181 and other post-traumatic biomarkers, including total-tau (t-tau), neurofilament light (NfL), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) and glial fibrillary acidic protein (GFAP), were assessed after moderate-to-severe TBI in the BIO-AX-TBI cohort (first sample mean 2.7 days, second sample within 10 days, then 6 weeks, 6 months and 12 months, n=42). Brain atrophy rates were assessed in aligned serial MRI (n=40). Concentrations were compared patients with and without Alzheimer’s disease, with healthy controls. Results: Plasma p-tau181 concentrations were significantly raised in patients with Alzheimer’s disease but not after TBI, where concentrations were non-elevated, and remained stable over one year. P-tau181 after TBI was not predictive of brain atrophy rates in either grey or white matter. In contrast, substantial trauma-associated elevations in t-tau, NfL, GFAP and UCH-L1 were seen, with concentrations of NfL and t-tau predictive of brain atrophy rates. Conclusions: Plasma p-tau181 is not significantly elevated during the first year after moderate-to-severe TBI and levels do not relate to neuroimaging measures of neurodegeneration

LARS-like symptoms in the general population may suggest the significance of postoperative functional problems and emotional implications of rectal surgery

Background & Aim. Sphincter-saving rectal surgery is prone to cause changes in bowel function associated with Low Anterior Resection Syndrome (LARS). Our aim was to assess LARS-like symptoms within a population of 50-80-year old in order to understand the functional disturbances and emotional impact of LARS. Materials and methods: We used a questionnaire to evaluate LARS with the following categories of symptoms: flatulence control, anal incontinence, frequency, clustering and urgency of the stools, and the psycho-emotional impact created by the presence of these symptoms. We calculated the severity of LARS on 343 responders. Results. The average age of the responders (57.4% females) was 60 years. Overall, 48.1% of those questioned had no LARS-associated symptoms, while the rest presented either minor (39.9%) or major (12%) LARS-like symptomatology according to the assessment scale. Women have a higher relative risk (1.32) of having minor or major LARS. The frequency of stools did not correlate with the overall LARS score. The psycho-emotional impact was mostly influenced by the presence of incontinence (p=0.001) and urgency (p=0.05). Discussions. The study highlights the need to integrate the initial status of patients into the overall quantification of the effects of surgery on the quality of life. Age does not influence the prevalence of LARS, but symptoms seem more prevalent in women. The psycho-emotional impact is relevant to the general population, so explanations given during the informed consent and accurate description of potential consequences of surgical intervention increase compliance to ensure better post-operative control of the symptomatology. Conclusions. Deriving a normative LARS-like score may alter the interpretation and discussion of LARS scores for future rectal cancer patients, and it also provides a better understanding of the emotional impact of such symptoms on certain population subsets or cultural groups

Axonal marker neurofilament light predicts long-term outcomes and progressive neurodegeneration after traumatic brain injury

Axonal injury is a key determinant of long-term outcomes after traumatic brain injury (TBI) but has been difficult to measure clinically. Fluid biomarker assays can now sensitively quantify neuronal proteins in blood. Axonal components such as neurofilament light (NfL) potentially provide a diagnostic measure of injury. In the multicenter BIO-AX-TBI study of moderate-severe TBI, we investigated relationships between fluid biomarkers, advanced neuroimaging, and clinical outcomes. Cerebral microdialysis was used to assess biomarker concentrations in brain extracellular fluid aligned with plasma measurement. An experimental injury model was used to validate biomarkers against histopathology. Plasma NfL increased after TBI, peaking at 10 days to 6 weeks but remaining abnormal at 1 year. Concentrations were around 10 times higher early after TBI than in controls (patients with extracranial injuries). NfL concentrations correlated with diffusion MRI measures of axonal injury and predicted white matter neurodegeneration. Plasma TAU predicted early gray matter atrophy. NfL was the strongest predictor of functional outcomes at 1 year. Cerebral microdialysis showed that NfL concentrations in plasma and brain extracellular fluid were highly correlated. An experimental injury model confirmed a dose-response relationship of histopathologically defined axonal injury to plasma NfL. In conclusion, plasma NfL provides a sensitive and clinically meaningful measure of axonal injury produced by TBI. This reflects the extent of underlying damage, validated using advanced MRI, cerebral microdialysis, and an experimental model. The results support the incorporation of NfL sampling subacutely after injury into clinical practice to assist with the diagnosis of axonal injury and to improve prognostication

Noble gas and carbon isotope systematics at the seemingly inactive Ciomadul volcano (Eastern‐Central Europe, Romania): evidence for volcanic degassing

Ciomadul is the youngest volcano in the Carpathian-Pannonian Region, Eastern-Central Europe, which last erupted 30 ka. This volcano is considered to be inactive, however, combined evidence from petrologic and magnetotelluric data, as well as seismic tomography studies suggest the existence of a subvolcanic crystal mush with variable melt content. The volcanic area is characterized by high CO2 gas output rate, with a minimum of 8.7 × 103 t yr-1. We investigated 31 gas emissions at Ciomadul to constrain the origin of the volatiles. The δ13C-CO2 and 3He/4He compositions suggest the outgassing of a significant component of mantle-derived fluids. The He isotope signature in the outgassing fluids (up to 3.10 Ra) is lower than the values in the peridotite xenoliths of the nearby alkaline basalt volcanic field (R/Ra 5.95Ra±0.01) which are representative of a continental lithospheric mantle and significantly lower than MORB values. Considering the chemical characteristics of the Ciomadul dacite, including trace element and Sr- Nd and O isotope compositions, an upper crustal contamination is less probable, whereas the primary magmas could have been derived from an enriched mantle source. The low He isotopic ratios could indicate a strongly metasomatized mantle lithosphere. This could be due to infiltration of subduction-related fluids and postmetasomatic ingrowth of radiogenic He. The metasomatic fluids are inferred to have contained subducted carbonate material resulting in a heavier carbon isotope composition (13C is in the range of -1.4 to -4.6 ‰) and an increase of CO2/3He ratio. Our study shows the magmatic contribution to the emitted gases