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Scanning probe methods, based on micro-electromechanical (MEMS) devices, have been employed to store data at ultrahigh densities (>Tbit/sq.in) with low power consumption. The use of microscopic conductive tip in contact with phase-change materials (PCM) is one such approach, with the aim to record data as amorphous or crystalline marks on a sample medium down to the nanometer scale. These applications rely on the reversible phase transition property of PCM between amorphous and (poly)crystalline state. Writing data is a complex process which involves electrical, thermal and phase-transition phenomena that determine the final size and shape of the written mark. Reading is based on the detection of the large difference between electrical conductivities of the two states of the phase-change medium. Towards a better understanding of these processes, numerical models, based on finite element methods (FEM), have been developed to simulate and analyze such a system. The objective of this paper is to present a theoretical study based on computational calculations, in order to predict the spatial distribution of amorphization during writing and derive the basic waveform of the read-back signal. [ABSTRACT FROM AUTHOR]

Hypoxia in coastal environments is a worldwide problem and is expected to worsen in future. Due to the stratification of the water column in many enclosed or semi-enclosed gulfs, deep waters are isolated and hypoxic or anoxic conditions frequently become dominant. The most common method for the oxygenation of these isolated anoxic water masses is vertical mixing. However, there are enclosed gulfs which rarely have the appropriate energy to ensure the mixing of the entire water column. The main purpose of this paper is to find if there are any other hydrodynamic processes which can cause oxygenation of deep waters, apart from vertical mixing. In order to achieve this aim, an enclosed gulf, Amvrakikos in Western Greece, was chosen to be the case study area and bimonthly physicochemical data were collected for one year and used in combination with a three-dimensional model in order to simulate the hydrodynamic circulation of the system. According to our results, another hydrodynamic process can lead to the oxygenation of the deepest water in an enclosed gulf. This process is the horizontal intrusion of well oxygenated water from the open sea. The key factor in determining the success of this horizontal intrusion is the density difference between the deepest area of the enclosed gulf and the open sea outside the gulf. From autumn to winter, when the open sea water is denser than that inside the gulf, the well oxygenated open sea water inflows into the gulf near the bottom sea floor and re-oxygenates the isolated deep waters through mixing. However, from spring to summer, when the deep water of the gulf is characterized by higher density in comparison with the open sea water, the inflow of well oxygenated water stops, causing the development of hypoxic/anoxic conditions during the summer months. [ABSTRACT FROM AUTHOR]

Background: Circulating polymerized mutant Z-alpha-1 antitrypsin (Z-polymer) constitutes a characteristic feature in alpha-1 antitrypsin deficiency (AATD), but there is limited knowledge about its association with adverse clinical outcomes and liver fibrosis. We explored this association using data from a large cohort of adults with AATD., Methods: A total of 836 (431 PiZZ, 405 PiMZ) adults with AATD and 312 controls (PiMM) from the European Alpha-1 Liver Cohort (2015-2020) were included. Time-to-event analyses were conducted for adults with the PiZZ genotype followed for adverse clinical outcomes (earliest occurrence of liver-related hospitalization, liver transplant or all-cause mortality). Cox proportional hazard models were used to describe the association between binary circulating Z-polymer levels and adverse clinical outcomes. Correlations between baseline circulating Z-polymer levels and baseline liver fibrosis (liver stiffness measurement [LSM] determined by transient elastography [FibroScan®]) were evaluated. The analyses were stratified by augmentation therapy status., Results: Of 324 adults with the PiZZ genotype and longitudinal follow-up data, 28 reported adverse clinical outcomes. Higher baseline circulating Z-polymer levels were associated with an increased risk of adverse clinical outcomes in both crude (hazard ratio [95% confidence interval, CI], 2.88 [1.21, 6.87]) and age-adjusted (1.96 [0.78, 4.94]) analyses. In adults with the PiZZ genotype, circulating Z-polymer levels were weakly positively correlated with baseline LSM (Spearman's rho [95% CI]: 0.21 [0.11, 0.31]). Similar results were observed after stratification by augmentation therapy status., Conclusions: In adults with the PiZZ genotype, higher circulating Z-polymer levels were associated with a shorter time to adverse clinical outcome, and positively correlated with baseline LSM. Circulating Z-polymer levels may be a prognostic biomarker of clinically relevant disease in AATD., (© 2024 The Author(s). United European Gastroenterology Journal published by Wiley Periodicals LLC on behalf of United European Gastroenterology.)

Hepatitis A virus can cause liver damage ranging from mild illness to fulminant hepatic failure, constituting 0.35% of all cases of fulminant liver failure. While rates of spontaneous remission are higher for hepatitis A, recent outbreaks attributable to vaccine shortages in highly populated urban cities plagued by insufficient affordable housing and inaccessible sanitation, and changes in the epidemiology of viral strains have resulted in increased hospitalizations and deaths. While the prognosis for patients with FHF has improved since the introduction of transplantation, the decision to transplant is often difficult to reach. We present five patients with HAV and subsequent FHF, one of whom successfully received a liver transplant. We have reviewed all published cases of HAV FHF in the literature and report ten patients, seven of whom received liver transplantation. There are few predictive models that attempt to distinguish between fulminant hepatitis A and spontaneous recovery. Patients found to have positive hepatitis A IgM, encephalopathy, worsening LFT's and coagulation should be monitored closely and referred to transplant centers urgently for management., (© 2020 Wiley Periodicals LLC.)

Purpose: Our purpose was to report outcomes in patients with Child-Pugh B or C (CP B/C) hepatocellular carcinoma (HCC) treated with stereotactic body radiation therapy (SBRT)., Methods and Materials: Patients with HCC suitable for SBRT were prospectively enrolled in the study from 2012 to 2018. Outcomes in patients with CP B/C were analyzed. Cox proportional hazard models were used to compare survival outcomes between baseline CP score and post-SBRT CP score., Results: Twenty-three patients with CP B/C with a total of 29 HCC tumors were treated with SBRT. Eighty-seven percent of patients were CP B8-C10. Median tumor size was 3.1 cm (range, 1-10 cm). Median dose delivered was 40 Gy in a median of 5 fractions. Eighteen of 23 patients (78.3%) had been previously treated with transarterial chemoembolization. Median follow-up was 14.5 months. Rates of 6- and 12-month local control were 100% and 92.3%, respectively. Six- and 12-month survival rates were 73.9% and 56.5%, respectively. Median survival was 14.5 months overall and 9.2, 22.5, 14.5, and 14.4 months for patients with CP B7, B8, B9, and C10, respectively. No patients exhibited symptoms of classic radiation-induced liver disease. However, 10 patients had CP score progression, with 4 patients (17%) having a ≥2-point increase in CP score by 6 months (or time of censor). There were 7 liver-related deaths, and based on independent review by a hepatologist, 1 of these deaths may have been attributable to SBRT-related liver injury. Fifteen of 23 patients were listed for liver transplant (LT) at the time of SBRT and 9 went on to receive LT with a pathologic complete response rate of 63.6%. Median survival, excluding patients who received LT, was 7.3 months., Conclusions: SBRT is a reasonable treatment option for carefully selected patients with CP B7-C10. In our small cohort, there was no detectable difference between local control or overall survival and baseline CP score., (© 2020 The Author(s).)

Lakes, representing major freshwater resources, play a crucial role for both humans and ecosystems. Based on the increasing international interest in the contamination of water resources by genotoxic compounds, the present study aimed to evaluate the genotoxic potential of surface water samples collected from the five (5) lakes (Amvrakia, Lysimachia, Ozeros, Trichonida, Kastraki) located in Aitoloakarnania regional unit (Western Greece). The genotoxic potential of surface water samples was evaluated by employing the Cytokinesis Block MicroNucleus (CBMN) assay in cultured human lymphocytes. In the former assay, lymphocytes were treated with 1, 2 and 5% (v/v) of surface water from each lake. Statistically significant differences (1.7 to 3.3 fold increase in MN frequencies vs. the control) were seen at the dose of 5% (v/v) in all studied lakes. At the dose of 2% (v/v) statistically significant differences (1.7 to 2.6 fold increase in MN frequencies vs. the control) were observed in all studied lakes except Trichonida lake. Finally, at the dose of 1% (v/v) statistically significant differences (2.3 and 2.5 fold increase in MN frequencies vs. the control) were observed in the Ozeros and Lysimachia lakes. The evaluation of the potential genotoxic effects and the analysis of the physicochemical parameters of lakes' surface water samples is a first step in our effort to evaluate the water quality, in terms of the presence and environmental/human risk of genotoxicants in the studied lake ecosystems. The present study showed for the first time the presence of genotoxic substances in surface waters of the studied lakes., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Patients with recurrent hepatitis C (HCV) infection post-liver transplant can be difficult to treat safely and effectively. A prior (COSMOS) study in patients with non-transplant HCV, using sofosbuvir plus simeprevir, had high efficacy and tolerability in treating patients with HCV genotype 1, even prior non-responders to interferon therapy and those with cirrhosis. Our aim was to evaluate the efficacy of sofosbuvir and simeprevir in patients with genotype 1 HCV post-liver transplant., Methods: In this prospective, observational study, patients received sofosbuvir 400 mg plus simeprevir 150 mg daily for 12 wk without ribavirin. The primary end point was a sustained virologic response 12 wk after the end of therapy., Results: Forty-two patients completed the treatment. Twenty-six percent started the treatment ≤ 6 months post-liver transplant. Nineteen percent of the included patients had cirrhosis, 14% with decompensation. At week 4 on the treatment, 21% of patients had detectable virus but at the end of the treatment, 100% were undetectable. Twelve weeks after the end of the treatment, 95% of the patients had undetectable hepatitis C. The regimen was generally well tolerated., Conclusion: The oral regimen of sofosbuvir plus simeprevir without ribavirin is efficacious and well tolerated in the treatment of patients with genotype 1 hepatitis C post-liver transplant., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Eutrophication has become the primary water quality issue for most of the freshwater and coastal marine ecosystems in the world. It is one of the most visible examples of biosphere's alteration due to human activities affecting aquatic ecosystems from the Arctic to the Antarctic. As eutrophication becomes frequent and many eutrophic ecosystems have difficulties meeting the EU Water Framework Directive (WFD) criteria the removal of phosphate and/or ammonium gains great importance, in water treatment. The objective of this paper is to review the restoration methods of eutrophic ecosystems, emphasizing remediation methods of internal nutrient release budget as a major factor to control eutrophication. The use of phosphate inactivation agents as a restoration tool, their capacity and application methods, as well as the individual results (in water quality, algal blooms, flora and fauna) in areas that have been implemented were also examined. Moreover, a conceptual model was conducted as a process to determine remediation technique, highlighting the need of an integrated approach to eutrophication management. The chemical lake restoration methods are not a panacea and their implementation should consist a targeted management approach as a part of an integrated management plan. The longevity of the treatment effectiveness using P-inactivation agents is reduced if not given the necessary importance in managing the external nutrient loads. The successful implementation of internal P management measures requires a site-specific study of a range of factors affecting viability of the method used, in connection with an assessment of the potential adverse effects on humans, livestock, biotic and abiotic factors., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Activated factor X (FXa) is an important player in the coagulation cascade responsible for thrombin generation, which is activated during atrial fibrillation. Increasing evidence suggests that FXa influences cell signalling in various cell types by activating protease-activated receptors (PARs). It is so far not known if molecular effects of FXa affect atrial signal transduction. To study the effects of FXa, human atrial tissue slices were cultivated with FXa up to 24h. Additionally, rapid pacing was applied at 4Hz to resemble atrial fibrillation. The inhibitory impact of FXa antagonist (Rivaroxaban), protease-activated receptor 1 antagonist (SCH79797), and protease-activated receptor 2 antagonist (GB83) were analysed under experimental conditions. The exposure of atrial tissue to FXa resulted in the 1.7 fold upregulation of PAR2-mRNA, activation of MAP kinases (ERK1/2) and NF-κB signalling. Furthermore FXa increased the expression of adhesion molecule ICAM-1 (1.82 ± 0.20), chemokine IL-8 (1.94 ± 0.20), as well as prothrombotic molecule PAI-1 (1.52 ± 0.17). The combination of rapid pacing and FXa caused significant upregulation of PAR1 (2.82 ± 0.22), PAR2 (2.66 ± 0.40), ICAM-1 (2.13 ± 0.25), IL-8 (2.22 ± 0.24), LOX-1 (2.59 ± 0.35), and PAI-1 (2.65 ± 0.52) at the mRNA level. Rivaroxaban and GB83 prevented upregulation of PARs, ICAM-1, LOX-1, IL-8, and activation of MAP kinases. The elevation in the expression of PAI-1 was hindered in the presence of SCH79797, or Rivaroxaban. The present study indicates that FXa mediates inflammatory signalling in atrial tissue. Importantly, FXa and tachyarrhythmia act synergistically to increase expression of protease-activated receptors and inflammatory mediators. Rivaroxaban prevented effectively FXa-induced molecular effects in human atrial tissue particularly during rapid pacing., (© 2013 The Authors. Published by Elsevier B.V. All rights reserved.)

Temporal and spatial distribution of physico-chemical and water quality parameters and their correlation with meteorological and hydrological data, was investigated for anoxic lagoons, in Greece. Monthly variations of parameters like temperature, salinity, dissolved oxygen, chlorophyll-a, total phosphorus etc., along the Aitoliko lagoon water column, were recorded and studied at 14 stations. Throughout the sampling period, in lagoon's water column three layers were determined: the surface low density layer (11.49-16.15), the layer with the steep density gradient and the deep dense (19.78-20.62) water below the depth of 20 m. The depth of the surface and pycnocline layers depends on seasonal surface salinity (20.53-22.43 per hundred) and temperature (12.48-28.40 degrees C) alterations. Lagoon's monimolimnion was extended, below the depth of 20 m and had constant temperature and salinity equal to about 13 degrees C and 27 per hundred respectively. Meteorological conditions control temperature (R2=0.845) and dissolved oxygen (R2=0.576) monthly changes, in lagoon's epilimnion, while salinity seems to be related with the salt/fresh water budget into Aitoliko lagoon. Epilimnetic chlorophyll-a (3.29-14.89 microg l(-1)) and total phosphorus (13.33-36.31 microg l(-1)) concentrations classify Aitoliko lagoon as a mesotrophic environment (40

Purpose: Polar chemical integrative samplers (POCIS) were examined for their sampling efficiency of 12 pesticides and one metabolite commonly detected in surface waters. Laboratory-based calibration experiments of POCISs were conducted. The determined passive sampling rates were applied for the monitoring of pesticides levels in Lake Amvrakia, Western Greece. Spot sampling was also performed for comparison purposes., Methods: Calibration experiments were performed on the basis of static renewal exposure of POCIS under stirred conditions for different time periods of up to 28 days. The analytical procedures were based on the coupling of POCIS and solid phase extraction by Oasis HLB cartridges with gas chromatography-mass spectrometry., Results: The recovery of the target pesticides from the POCIS was generally >79% with relative standard deviation (RSD) <16%. The calibration results revealed an integrative uptake of all pesticides for 28 days and the calculated sampling rates ranged from 0.025 to 0.388 L day(-1) with RSD <29%. Low nanogram/liter levels of pesticides such as diazinon, alachlor, and s-metolachlor were detected during the monitoring campaign using both passive and spot sampling whereas higher concentrations were measured by spot sampling in most cases., Conclusions: Passive sampling by POCIS provides a useful tool for the monitoring of pesticides in aquatic systems since integrative sampling at rates sufficient for analytical quantitation of ambient levels was observed. Calibration data are in demand for a greater number of compounds in order to extend the use in environmental monitoring.

The spatiotemporal changes of metals, inorganic ions and physiochemical parameters of Aitoliko lagoon, an anoxic wetland in Western Greece, were studied with special emphasis in sulfur species. Theoretical physicochemical modeling was performed for the sulfur speciation, based on experimental pH and redox potential data. Accordingly, the speciation of sulfur in the lagoon can be operationally divided in two domains: (a) for depths d = 0-10 m below the surface, the sulfur speciation can be described by equilibrium reactions between the aqueous species. (b) At depths d > 10 m a progressive decline for SO4(2-) concentration is observed between theory and experiment. At the lagoon-bottom an elevated concentration of 19+/-2 mM SO4(2-) was measured, which cannot be described by physicochemical equilibrium based on the pH, E(h), O2 concentrations measured in situ. Accordingly, we suggest that additional biogeochemical processes, such as sulfur bacteria activity, have to be invoked. Of particular importance is that the experimental pH-pe values cross the critical region where the interplay of SO4(2-)/S2(-)/H2S occurs. This explains why a relatively small fluctuation of pH, pe values may result in a shift of the equilibrium over one sulfur species. This explains the, otherwise accidental, previously reported releases of H2S in the air over the lagoon.

Industrial and agricultural activities often impose significant pressures to the groundwater quality and consequently degrade wetland ecosystems that depend mostly on subsurface water flow. Groundwater vulnerability and risk mapping is a widely used approach to assess the natural protection of aquifers and the associated pollution potential from human activities. In the particular study, the relatively new Pan-European methodology (COP method) has been applied in a highly industrialized peri-urban wetland catchment, located close to Athens city, to map the intrinsic vulnerability of the aquifer and evaluate the risk potential originating from local land uses. Groundwater analysis results for various parameters, including Phenols, PCBs and nutrients, have been used to validate the vulnerability and risk estimations while a biological assessment occurred to associate the mapping results with the wetland's ecological status. The results indicated that even though the natural protection of the aquifer is relatively high due to the dominant hydrogeologic and geomorphologic conditions, the groundwater pollution risk is considerable, mainly because of the existing hazardous land uses. The water quality of the groundwater accredited these findings and the ecological status of this peri-urban wetland also indicated significant impacts from industrial effluents.

Background & Aims: Methasteron is a nutritional supplement used to increase weight or accelerate the build-up of muscle mass. The aim of this study was to describe 5 cases of hepatotoxicity in patients using methasteron seen at tertiary-care medical centers., Methods: A case report design was used., Results: Five previously healthy patients who used methasteron developed jaundice 2 weeks after discontinuation; they presented to a tertiary-care medical center 2 weeks later. Within another 2 to 3 weeks, bilirubin levels peaked. About 12 weeks after initial presentation, all cases resolved with no identifiable residual hepatic dysfunction., Conclusions: Methasteron use can result in severe hepatotoxicity. Liver failure can worsen after initial presentation, especially within 2 weeks. With close observation and supportive care, acute hepatic injury should resolve.

Objectives: Construction of the newly developed "ICD-10 Symptom Rating" (ISR) is presented together with some statistical data. This questionnaire is founded on the well-known ICD-10, according to which symptoms are relevant for assessing psychological disorders. The ISR aims at a comprehensive evaluation of the severity of psychological disorders. The ISR 2.0 has 29 items and six syndrome scales: Depression, Anxiety, Obsessive/Compulsive, Somatoform, Eating Disorders, and the Supplementary Scale, which covers a variety of syndromes, as well as a total score., Methods and Results: In a first cross-validation with 108 patients, some rather high correlations were found between the SCL-90-R and the ISR. They ranged from r = 0.78 to 0.37 for the individual syndrome scales, and amounted to r = 0.78 for the GSI versus the total score.

Mediterranean temporary ponds (MTPs) comprise an endangered habitat with several endemic species that can be found in many countries, mainly in the Mediterranean region but are disappearing at a high rate. For designing optimal conservation and management strategies for the particular ecosystems, appropriate characterization and classification of these ponds is necessary based on the different type of habitats and on their varying environmental conditions. This paper presents the current ecological status and the threats of Mediterranean temporary ponds and summarizes some management and conservation issues based on the existing experience on a regional level. Emphasis is given in the Greek MTPs with respect to their characteristics and the pressures received mainly from human activities such as agriculture and water overexploitation. Restoration practices should be commenced immediately aiming at the reestablishment of the ponds' hydroperiod and water quality at the natural levels.

Toward developing a transducer for measuring in vivo tension in anterior cruciate ligament grafts in humans, the objectives of this study were to determine the following: (1) whether the calibration of a previously reported femoral fixation device transducer (FDT) (Ventura et al., 1998) is affected by the presence of the graft when implanted in the tibial metaphysis of an ovine model, (2) whether the FDT remains calibrated at 4 weeks postoperatively, and (3) whether the biological incorporation of the graft occurs prior to a change in the FDT calibration. The FDT was implanted in the hind limb of five sheep using an extra-articular procedure. Both the proximal common digital extensor tendon (i.e., graft) and a Teflon-coated wire were looped around the FDT inside a tunnel in the tibial metaphysis. The FDT was calibrated on three occasions using the loop of wire: once intraoperatively before graft insertion, once intraoperatively after graft insertion, and once postoperatively after the animals had been sacrificed at 4 weeks. Following sacrifice, the load transmitted to the FDT by the graft was also determined. The FDT exhibited linear calibration intraoperatively both before and after graft insertion with an average error relative to the calibration before insertion of the graft of -4.6 percent of full-scale load (150 N) and this average relative error was not significantly different from zero (p = 0.183). After 4 weeks of implantation, the average relative percent error was -5.0 percent and was not significantly different from zero (p = 0.434) indicating that the FDT remained calibrated in the in vivo environment. Because only 15 percent of the graft tension was transmitted to the FDT after 4 weeks, biological incorporation of the graft preceded the loss of calibration. In light of these findings, the FDT offers the capability of measuring the intra-articular ACL graft tension in vivo in animal models and possibly humans before the biological bond develops and also of monitoring the formation and maturation of the biological bond between a graft and bone tunnel.

To determine which exercises do not overload the graft-fixation complex during intensive rehabilitation from reconstructive surgery of the anterior cruciate ligament (ACL), it would be useful to measure ACL graft loads during rehabilitative activities in vivo in humans. A previous paper by Ventura et al. (1998) reported on the design of an implantable transducer integrated into a femoral fixation device and demonstrated that the transducer could be calibrated to measure graft loads to better than 10 percent full-scale error in cadaveric knees. By measuring both the static and fatigue strengths of the transducer, the purpose of the present study was to determine whether the transducer could be safely implanted in humans without risk of structural failure. Eight devices were loaded to failure statically. Additionally, seven devices were tested using the up-and-down method to estimate the median fatigue strength at a life of 225,000 cycles. The average ultimate strength was 1856 +/- 74 N and the median fatigue strength was 441 N at a life of 225,000 cycles. The maximum graft load during normal daily activities is estimated to be 500 N and the 225,000 cycle life corresponds to that of the average healthy individual during a 12-week period. Considering that patients who have had an ACL reconstruction are less ambulatory than normal immediately following surgery and that biologic incorporation of the graft should be well developed by 12 weeks thus decreasing the load transmitted to the fixation device, the FDT can be safely implanted in humans without undue risk of structural failure.