Higher Values In Samples Research Articles

Implant Stability and Histomorphometric Analysis Comparing Two Different Implant Macrogeometries Placed in Fresh Sockets: An Experimental Study in Sheep.

The aim of the present animal study was to examine the impact of two implant designs that promote different insertion torque values on implant stability and evaluate, histomorphometrically, the bone healing for immediate implant placement in fresh sockets. Twelve female sheep (35.0±5.0kg) and 48 conical Morse-taper dental implants divided into two groups (n = 24 per group): G1 group, where the implants present a design that can provide high insertion torque values; and G2 group, where the implants present a design that can provide low insertion torque values. Both had the same surface treatment, and dimensions (4.0 mm in diameter and 10 mm in length). The first two posterior teeth (both sides) were extracted carefully. Sequentially, there were osteotomies in the mesial socket of each molar tooth. The final implant position was 2 mm below the buccal bone crest level. On the right side, implants of the G1 were placed anteriorly, followed by implants of the G2; and, on the left side, it was the reverse. A digital torquemeter was used to measure the maximum final insertion torque value (f-IT). The initial implant stability quotient (ISQ) was measured immediately after the implant insertion (T0) and immediately after the euthanasia and removing the mandibles with the implants. The animals were euthanized (n=6 animals/ time) at 21 days (T1) and 35 days (T2). The t-test was used to compare statistical differences for each intragroup parameter analyzed. Pearson's correlation was used to analyze possible correlations: f-IT and BIC%, f-IT and ISQ, and ISQ and %BIC. Regarding the insertion torque, the G1 presented higher values than the G2, with a statistically significant difference (p<0.0001). The ISQ mean values were higher in the B-L direction than those obtained for M-D for both groups. %BIC measurements showed higher values in samples from G2 than G1 at both times and in both directions. New bone, medullary spaces, and collagen matrix had statistical differences between the groups at each evaluation time. Using implants with a modified macrogeometry plays a significant role in implant stability and the healing process of bone tissue around the implant. It is important for clinicians to carefully consider implant macrogeometry when planning dental implant surgery to achieve optimal implant stability and successful osseointegration, mainly in cases of immediate implant placement.

Identification of freshwater microbiota and physicochemical analysis of water Waduk Lhok Batee Jeumpa

Biota components can provide an overview of the physical, chemical and biological conditions of a waters. One biota that can be used as a biological parameter in determining the condition of a waters is biota. Changes in the quality of water and its living substrate greatly affect the abundance and diversity of biota. The aim of this study was to identify fresh water microbiota and physicochemical analysis of water in the Lhok Batee Jeumpa Reservoir. The research method used is a combination of qualitative and quantitative research. Based on the research results, there are 13 types of Plankton consisting of 12 families in the Lhok Batee Reservoir. Plankton diversity is included in the low category with a diversity index of 0.4296. Dissolved Oxygen (DO) levels obtained the lowest value in sample 2-A of 4.70 mg/L and the highest value in samples 1-B, 4-B and 5-A of 5.20 mg/L, according to the standard quality Class 2 (4 mg/L). Biochemical Oxygen Demand (BOD) levels obtained the lowest value in sample 5-A of 1.00 mg/L and the highest value in sample 3-A of 12.50 mg/L, in accordance with Class 2 quality standards (3 mg/ L). Chemical Oxygen Demand (COD) levels obtained the lowest value in sample 1-B of 20.22 mg/L and the highest value in sample 5-B of 84.76 mg/L, according to Class 2 quality standards (25 mg/L).

Planktic foraminifera iodine/calcium ratios from plankton tows

Planktic foraminifera test iodine to calcium ratios represent an emerging proxy method to assess subsurface seawater oxygenation states. Several core-top studies show lower planktic foraminifera I/Ca in locations with oxygen depleted subsurface waters compared to well oxygenated environments. The reasoning behind this trend is that only the oxidized species of iodine, iodate, is incorporated in foraminiferal calcite. The I/Ca of foraminiferal calcite is thought to reflect iodate contents in seawater. To test this hypothesis, we compare planktic foraminifera I/Ca ratios, obtained from plankton tows, with published and new seawater iodate concentrations from 1) the Eastern North Pacific with extensive oxygen depletion, 2) the Benguela Current System with moderately depleted oxygen concentrations, and 3) the well oxygenated North and South Atlantic. We find the lowest I/Ca ratios (0.07 µmol/mol) in planktic foraminifera retrieved from the Eastern North Pacific, and higher values for samples (up to 0.72 µmol/mol) obtained from the Benguela Current System and North and South Atlantic. The I/Ca ratios of plankton tow foraminifera from environments with well oxygenated subsurface waters, however, are an order of magnitude lower compared to core-tops from similarly well-oxygenated regions. This would suggest that planktic foraminifera gain iodine post-mortem, either when sinking through the water column, or during burial.

Contamination status of paralytic shellfish toxins in shellfish from Southeastern China in 2017-2021.

Harmful algal blooms is a widespread problem in aquatic ecosystems, in particular dinoflagellates that produce PSTs which are harmful to animal and human health. To explore the contamination status of PSTs in shellfish in the Southeastern China, a total of 2355 shellfish samples were analyzed by ultra high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to study the toxin profiles of the 10 PSTs collected from the southeast coast of China from 2017 to 2021. From 2355 shellfish samples, 257 were detected (10.91%), with the highest value in samples of Perna viridis. Among the six source areas in China, the samples from Fujian recorded the highest detected rate (15.28%). PSTs were found in Fuzhou, Ningde, Quanzhou, Putian, Zhangzhou, and Xiamen, with Quanzhou and Fuzhou having the highest and lowest detection rates of 15.28% and 4.23%, respectively. Saxitoxin (STX), neosaxitoxin (neoSTX), gonyautoxin (GTX1, GTX2, GTX3, GTX4), N-sulfocarbamoyl toxin (GTX5), and decarbamoyl toxin (dcSTX, dcGTX2, dcGTX3) were detected, and GTX5 and dcGTX2 were dominant. In addition, the samples containing PSTs were mostly concentrated in May to August. The study confirms the risks of PSTs to shellfish consumers in the region. It will offer a great foundation for future monitoring of marine toxins and protecting the health of seafood consumers in China. This is the first detailed evaluation of PSTs occurrences and their profiles in shellfish from the Southeastern China over a period of multiple years. HIGHLIGHTS: 2355 mussels from China were analyzed by UPLC-MS/MS for PSTs in 2017-2021. The predominant PSTs were GTX5, neoSTX and dcGTX2. Arca granosa and Crassostyea gigas exhibited higher levels than other shellfish. Shellfish containing PSTs were mostly concentrated in May to August. Maximum detected level in shellfish was 2137.10 ug STXeq/kg.

Effect of Red Lentil Flour Addition on Total Polyphenols Content and Antioxidant Capacity of Frozen Dough Bread

The fortification of frozen dough improved with addition of pulse flour - red lentil flour in various proportions (15% and 30%) was analyzed in order to raise the protein content, total polyphenol content (TPC) and antioxidant capacity (expressed using DPPH and CUPRAC methods) of wheat bread obtained from frozen dough. The high-protein, phenolic and flavonoid compounds potential of red lentil was considered for expanding the range of products obtained from frozen dough and physicochemical attributes (acidity, moisture porosity and ash content) were analyzed. Results showed that the bread formulated with 30% red lentil flour had the highest antioxidant capacity. The protein content showed higher values for samples with fortification, freezing treatment not affecting the content. The results denoted that enrichment of wheat dough with red lentil flour significantly increases the levels of polyphenols and the antioxidant activity of the final products. A strong increasement of phenolic compounds content was observed for the frozen samples, differences between fermented and unfermented samples and frozen and unfrozen samples varying significantly.

Coal characterization and coalbed methane potential of the Chico-Lomã Coalfield, Paraná Basin, Brazil – Results from exploration borehole CBM001-CL-RS

The aim of this study was to determine the coal characteristics in the Chico-Lomã coalfield, Brazil and to evaluate the potential of natural gas associated with the coal seams (CBM), by carrying out a test well (CBM001-CL-RS) for collecting coal samples, followed by gas desorption measurements, and petrographical and chemical analyses of the coals and their methane adsorption capacities. The gas collected was analyzed for gas composition, stable carbon and hydrogen isotopes. The results indicate a cumulative coal thickness of 11.46 m in well CBM001-CL-RS, associated with an igneous intrusion of 10 m thickness. In the contact zone with the intrusion, the organic matter is severely altered with partial transformation of the coal to natural coke at distances less than 2 m from the intrusion. The ash content, based on proximate analysis, shows a variation from 29.1 to 82.8 wt.%. The sulphur content ranges from 0.43 to 3.89 wt.% and shows higher values in samples from the top of the Rio Bonito Formation. The gas desorption measurements range from 0.05 to 0.74 cm3/g, with methane being the predominant gas (&gt;90%). A thermal origin of the gas is suggested by C and H isotopes and the C1 (methane) to C3 (propane) hydrocarbon distribution. The methane adsorption capacity of the samples varies from 2.50 to 6.50 cm3/g. Changes in microporosity related to thermal alteration may have a significant impact on the gas-holding capacity of samples located near the contact to the intrusion. For the study area, a 3D geological model was generated to estimate the volume of coal in the coalfield, followed by assessment of the gas volume associated with the coal. Based on the 3D model, a preliminary appraisal indicates resources of 7.2 billion tons of coal for the Chico-Lomã coalfield, associated with 2.7 billion m3of gas.

Heavy metal contents and enzymatic activity in soils exposed to the impact of road traffic

The aim of the research was to evaluate the influence of car traffic on the content of selected heavy metals in soil from a park area, and to define the dependency between their content and enzyme activity. Soil samples were collected from 13 points located along a communication route, each 100 m from the next and 50 m from the border of the road. Soil material was obtained from two depths (0–20 cm and 20–40 cm) and analysed for: pH in H2O and in KCl, OC, and texture by laser method. Total content of heavy metals (Pb, Cd, Zn, Cu, Ni), available phosphorus and the activity of selected enzymes: catalase, dehydrogenase, acidic and alkaline phosphatase were all determined. The examined soils have the texture of loamy sands or sands (USDA 2012), slightly acidic or neutral pH, Organic Carbon (OC) content in the range from 3.50 to 13.80 g kg−1. The total contents of elements in surface horizons were, in order of decreasing concentrations: Pb>Zn>Cu>Ni>Cd, although in subsurface horizons it was Zn>Pb>Cu>Ni>Cd. Contamination Factor (CF) determined for Ni, Pb, Cd, Zn, Cu reaches higher values in samples from subsurface horizons, which confirms the influence of car traffic on the content of heavy metals in the surrounding soils. The calculated CF shows contamination is moderate for Ni, Cd, Zn and Cu and high for Pb and Cu. The investigated soils may be classified as class IV (low) in terms of available phosphorus. The activity of the examined enzymes was higher in soil samples collected from the 0–20 cm layer than from 20–40 cm. The correlation analysis indicates a significant positive dependency between OC content in soils and enzymatic activity. Principal Component Analysis (PCA) was also performed. Two principal components PC1 and PC2 account for 66.57% of the variability.

Preliminary Data Regarding Total Chlorophylls, Carotenoids and Flavonoids Content in Flavoparmelia Caperata (L.) Hale Lichens Species

Flavoparmelia caperata L. Hale (common greenshield lichen) is an Ascomycete, foliose lichen usually growing on tree bark in most mesophytic-forested habitats in Romania. Lichen samples were collected from three stations in Romania (Craiova, Timișoara, Hoia-Baciu Forest, Cluj) and extracted in 96% ethanol. Both dry lichen tissue powder and extracts were analyzed by UV-Vis spectrophotometry for determining photosynthetic pigment concentrations (chlorophylls a and b and total carotenoids). Dry tissue samples had chlorophyll a concentrations of 95.12-109.59 mg/kg DW, chlorophyll b concentrations of 88.53-110.98 mg/kg and total carotenoids 88.89-102.85 mg/kg. Alcoholic extracts of fresh lichen tissue showed an extreme variability, with 715.97-10331.50 mg/kg chlorophyll a, 527.77-8124.20 mg/kg chlorophyll b, 1125.72-8714.90 mg/kg carotenoids pigments, with the highest values in samples from Craiova. A lower variability was observed in flavonoid contents, with 461.78-966.02 mg/kg DW in dry powder and 815.56-2734.135 mg/kg in ethanolic extracts. Extracts of lichens from Craiova had a decreased content of total flavonoids compared with the other two lichens ethanol extracts.

Inter-regional variation in feeding patterns of skipjack tuna (Katsuwonus pelamis) inferred from stomach content, stable isotope and fatty acid analyses

Foraging habits of skipjack tuna, SKJ (Katsuwonus pelamis), were investigated in three Spanish marine regions (Balearic Sea, Alboran Sea and Gulf of Cadiz) using stomach content (SCA), stable isotope (SIA), and fatty acid (FA) analyses. The three methodological approaches yielded significant differences among locations. All the studied areas appear to serve as important foraging grounds for SKJ, but the diet composition significantly varied among them. The predominant prey species in the respective locations were the North Atlantic krill, Meganyctiphanes norvegica, in the Balearic Sea, the flyingfish, Exocœtus volitans, in the Alboran Sea, and the anchovy, Engraulis encrasicolus, in the Gulf of Cadiz. Regional differences were also found in δ13C and δ15N values; furthermore, the analysis of standard ellipse areas (SEAc) based on isotopic data showed that the broadest niche corresponded to SKJ from the Gulf of Cadiz, with no significant isotopic niche overlap between areas. Consistent with the SCA and stable isotope results, the FA composition varied among areas. Docosahexaenoic acid (DHA, 22:6n-3) was the most abundant FA in the SKJ muscle, showing its highest values in samples from the Gulf of Cadiz; this FA was the most effective in segregating SKJ geographical groups. In conclusion, this study provides evidence that SKJ in eastern Atlantic and western Mediterranean waters can easily adapt their diet to local prey availability. Furthermore, stable isotope signatures and FA profiles of muscle tissue prove to be reliable trophic markers that allow separation of populations occurring in different marine areas.

Biogenic amines evaluation in wild Bluefin tuna (Thunnus thynnus) originating from various FAO areas

The total of 84 Bluefin tunas (Thunnus Thynnus) were analysed in order to obtain an overview of biogenic amines incidences in geographically distant capture fishing FAO (Food and Agriculture Organization of the United Nations) zones: Western Indian Ocean (51), Mediterranean Sea (37), Western Central Pacific Ocean (71) and Eastern Central Atlantic Ocean (34). Cadaverine and putrescine were remarkably accumulated in some samples, whereas histamine and spermidine were less abundant, but more frequently present. Histamine concentration was very low in all groups, having the highest value in samples from FAO 51 (median with 25th–75th percentile = 9.3, 4.4–13.4 mg kg−1). Cadaverine was completely absent from tunas deriving from FAOs 51, 37 and 71, while Atlantic Ocean samples demonstrated its noticeable presence (median with 25th–75th percentile = 34.7, 17.6–66.9 mg kg−1). Putrescine generally followed the cadaverine occurrence, but its levels remained very low: FAO 51 and 37 did not reveal any presence, while in FAO 71 slightly elevated concentrations appeared (median with 25th–75th percentile = 6.1, 0–43.3 mg kg−1). There were no significant differences in spermine levels between FAO groups. The results indicate that the established capture, post-capture and storage practices used for Bluefin tunas ensure good quality. A hazardous content could not be detected in the investigated samples and a health risk does not exist. Reported differences in biogenic amine quality and quantity are provoked by environmental conditions and individual variation between FAO areas.

Physical Parameters, Total Phenolics, Flavonoids and Vitamin C Content of Nine Sweet Cherry Cultivars

Sweet cherry tree (Prunus avium L., Rosaceae) is a species with high economic efficiency in production and in the last twenty years the scientific interest increased in the North-East region of Romania. In the area of Ia�i in 2014 the combined influence of the fruits position on tree level in different cultivars was recorded in terms of morphological and biochemical characteristics for nine different cultivars ex situ collected. Fruits collected from two different height-levels areas of tree were used for analysis in each cultivar. Fruit pulp and kernel were investigated in terms of biometry, total solids content, vitamin C, total flavonoids (flavones), and polyphenols. Fruit mass and diameter showed higher values in samples collected from the upper side of the tree on Catalina, Scorospelka, Van and Bucium�cultivars, ranging between 5.8 g / fruit to 9.5 g / fruit and 20.6 to 26.3 mm / fruit respectively. Kernel mass was higher on upper side of the tree on Catalina and Marina cultivars, while on Scorospelka, Van, Bucium and Stefan the values were greater on down half of the tree but without statistical signification. Total solids content of the fruit recorded values between 13.7 to 21.15%, the highest values being recorded in fruits sampled from the upper half of the tree on Catalina, Rivan�, Bucium, Stefan, Galata and Marina cultivars. Total flavonoids content recorded values ranging from 2.45 to 4.84 mg catechin g-1 DW, with increased values for samples collected from the upper part of the tree. Vitamin C content shows values ranging from 1.98 to 8.62 ascorbic acid 100 g-1 DW, the greater value being recorded for Stefan�cultivar from the upper side of the tree.

THE POTENTIAL IMPACT OF LANDFILL ON THE NEAR VICINITY WITH THE USE OF HEAVY-METAL ACCUMULATOR PLANTS

This study was conducted to screen plants growing on potentially contaminated areas of landfill body and nearest surrounding to determine their potential for metal accumulation. In addition, enrichment coefficient (EC) for plant/soil system, correlation and principal component analysis were used for determining the environmental contamination from landfill in terms of heavy metal (HM) accumulation. The examined plant samples meet the stated requirements. The highest values in samples 1 -8 reached Fe (491 191 000 mg/kg DM), the second values were Mn (35.1 342 mg/kg DM) and the third was Zn (26.9 145 mg/kg DM). The highest concentrations of Co, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were observed (in order) in plant samples 4, 2 and 1, i.e. plants collected in the vicinity of the landfill. The examined soil samples meet the stated requirements. The highest values in samples 1 -8 reached Fe (23 300 to 63 400 mg/kg DM), the second were recorded for Mn (527-908 mg/kg DM) and the third was Zn (83.0 -519 mg/kg DM). The highest concentrations of Co, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were observed (in order) in soil samples 7, 2 and 5. EC was calculated for all 8 sampling points. The highest degree of accumulation was observed for Cd in all 8 sampling points. In contrast, the lowest concentration of all the examined heavy metals was determined for Cd in plant and soil samples.

Preparation of random poly(butylene alkylate-co-terephthalate)s with different methylene group contents: crystallization and degradation kinetics

Random copolyesters having 1,4-butanediol units were synthesized from a transesterification process between homopolymers constituted by aliphatic dicarboxylates (i.e. succinate, adipate or sebacate) and the aromatic therephthalate derivative, as verified by NMR spectroscopy. Biodegradability of resulting copolyesters was studied via enzymatic hydrolysis using Pseudomonas cepacia lipase at pH = 7.2 and 37 °C. Kinetics of degradation showed that in all cases the degradation rate decreased after 19 days of exposure. The observed glass transition temperatures, T g, of the random copolyesters showed a non-linear dependence on composition, a feature that was explained in terms of the internal stiffening effect of butylene terephthalate units. Copolymers with higher aliphatic (i.e. 50 and 70 mol-%) and methylene (i.e. adipate and sebacate units) contents showed double melting peaks in DSC thermograms. These copolyesters resulted in two different crystalline rich phases after melt-crystallization and subsequent cooling. The ratio between these phases logically depended on the predominant aliphatic or aromatic dicarboxylate content. The copolymers initially crystallized via the aromatic units through a heterogeneous nucleation and a spherulitic growth. The presence of aliphatic dicarboxylate units hindered the beginning of the crystallization process, but the overall growth kinetic constant was similar for all samples. The secondary nucleation constants were determined and showed higher values for samples with higher adipate and sebacate contents.

The 137Cs activity concentration of suspended and dissolved fractions in irrigation waters collected from the 80 km zone around TEPCO's Fukushima Daiichi Nuclear Power Station

Fifty-four samples of irrigation water were collected in 2014 from agricultural ponds, rivers, and dams within the 80 km zone around TEPCO's Fukushima Daiichi Nuclear Power Station (FDNPS). The samples were filtered with a 0.45 μm pore-size membrane filter to produce suspended and dissolved fractions. The 137Cs activity concentration of the suspended fraction varied from 1.5 to 300 Bq g−1 dry weight and was significantly higher than that in the soil around each sampling site. The range of 137Cs activity concentrations in the dissolved fraction varied over three orders of magnitude at 0.0075–6.7 Bq l−1, which was a larger range than that of the suspended fraction; the higher values for samples were from within the 20 km zone. In the dissolved fraction 87 ± 9% of the 137Cs (n = 37) was in a monovalent cationic form (Cs+) and therefore potentially mobile. The distribution coefficient (Kd) ranged from 4100 to 2,100,000; the geometric mean value (110,000) was higher than that reported by the IAEA (2010). The geometric mean Kd of samples collected from the 20 km zone was 61,000 (n = 27), which was significantly lower than that collected from 20 to 80 km zone (200,000, n = 27). The Kd-value was negative correlated with the concentration of stable 133Cs and the electric conductivity in the dissolved fraction. This shows relatively higher mobility of radiocaesium in irrigation waters may occur when there are higher contents of cations present.

SELECTED PLASMA BIOCHEMISTRY ANALYTES OF HEALTHY CAPTIVE SULCATA (AFRICAN SPURRED) TORTOISES (CENTROCHELYS SULCATA).

The sulcata or African spurred tortoise (Centrochelys sulcata) is a large tortoise species that is commonly kept in zoologic collections and as a pet. The objectives of this study were to establish reference intervals for selected biochemical analytes in clinically healthy captive sulcata tortoises and to evaluate the impact of blood sampling site and sex. Blood samples were collected from 60 tortoises from either the dorsal coccygeal (tail) vein or the subcarapacial venous plexus based on their body size. The packed cell volume and refractometric total solids (TS) were determined. The concentrations of selected plasma biochemical analytes were determined using the VetScan VS2 analyzer and included albumin, aspartate aminotransferase, bile acids, calcium, creatine kinase, globulins, glucose, potassium, sodium, phosphorous, total proteins (TP), and uric acid. The calcium-to-phosphorous ratio was calculated. Reference intervals were determined and evaluated for the potential effects of blood sampling site and sex. There were significant differences (P < 0.05) associated with the blood sampling site in TS, TP, phosphorus, and globulins, with higher values in samples from the tail versus the subcarapacial sampling site. No significant statistical differences were noted in the plasma biochemistry analytes between the sexes. Reading of the globulins by the analyzer failed in 36 of 60 of the samples and was largely associated with the subcarapacial plexus sampling site. The reference intervals defined by the VetScan analyzer in this study can be used for clinical medicine and conservation of this tortoise species. Sampling site was identified as a factor significantly affecting some blood analytes in this study; this factor should thus be taken into consideration when assessing sulcata tortoise health status and using this testing methodology.

Effects of Selected Herbicides on Growth and Nitrogen Fixing Activity of Stenotrophomonas maltophilia (Sb16)

A study was carried out to determine the effects of paraquat, pretilachlor and 2, 4-D on growth and nitrogen fixing activity of Stenotrophomonas maltophilia (Sb16) and pH of Jensen's N-free medium. The growth of Sb16 and pH of medium were significantly reduced with full (X) and double (2X) doses of tested herbicides, but nitrogen fixing activity was decreased by 2X doses. The nitrogenase activity had the highest value in samples treated with 1/2X of 2, 4-D on fifth incubation day, but 2X of 2, 4-D had the most adverse effect. An inhibition in the growth and nitrogenase activity was recovered on the last days of incubation.

Volatile compounds profile of sous-vide cooked pork cheeks as affected by cooking conditions (vacuum packaging, temperature and time).

The volatile organic compound (VOC) profile of pork cheeks as affected by the cooking conditions was investigated. Pork cheeks were cooked under different combinations of temperature (60 °C or 80 °C), time (5 or 12 h) and vacuum (vacuum or air-packaged). As a general rule, the VOCs originating from lipid degradation were positively affected by the cooking temperature and negatively by the cooking time, reaching the highest amounts in pork cheeks cooked at 80 °C during 5 h and the lowest in samples cooked at 80 °C during 12 h. On the contrary, VOCs originated from amino acids and Maillard reactions were positively affected by both factors. The proportion between lipid degradation and amino acids reactions was estimated by the hexanal/3-methylbutanal ratio, which reached its highest values in samples cooked at 60 °C during 5 h in the presence of air and the lowest values in samples cooked at 80 °C during 12 h, regardless of the vacuum status.

Structure And Properties of the Centrifugally Cast High-Alloyed (25Cr35NiNbTi) Steel after Long-Time Operation in Steam Reforming

Abstract The paper presents the influence of performance conditions of high-alloyed nickel-chromium cast steel intended for use in steam reforming plants on the morphology and number of phases present in centrifugally cast tubes. Structure identification was done by the methods of light and scanning microscopy. It was found that the main components of the tested cast steel microstructures are carbides of, among others, chromium, iron, and niobium. The structure has also been reported to contain the sigma phase. Additionally, at three test temperatures (20, 820 and 945°), the mechanical properties of the cast steel were determined after years of operation under industrial conditions. The tested material was characterised by low, compared with standard requirements, mechanical properties. A relationship between the content of phases (primary and secondary carbides), measured by the methods of quantitative metallography, and the yield strength of the tested material was determined. The yield strength determined at room temperature, and at 820° and 945° assumed higher values in samples characterised by a relatively large volume content of phases.

Quantitative measurement of the sea ice diatom biomarker IP25 and sterols in Arctic sea ice and underlying sediments: Further considerations for palaeo sea ice reconstruction

The lipid content of sea ice samples collected in 2011 and 2012 from Resolute Passage in the Canadian Arctic Archipelago was measured and compared with related samples obtained from the Amundsen Gulf in 2008. The highly branched isoprenoid (HBI) sea ice biomarker, IP25, was found in sea ice samples from each study, consistent with its formation by diatoms during the spring bloom. Our analysis also revealed the occurrence of a number of sterols in Arctic sea ice and these were rigorously identified and quantified for the first time. Concentrations of IP25 and sterols exhibited some variability between sampling studies, with somewhat higher values in samples from Resolute in 2012 than for the other two datasets, consistent with a general increase in biomass; however, major differences in biomarker concentration between sampling studies were not observed. An estimate of the proportion of Arctic sea ice diatoms that produce IP25 (ca. 1–5%) was obtained by comparison of the concentration of IP25 in the samples with those in laboratory cultures of known HBI-producing diatoms and cell enumeration in selected sea ice samples. The estimate is similar to the proportion of Haslea spp. in the same samples, providing further support to the suggestion that at least some species of the Haslea genus may be responsible for the biosynthesis of IP25 and related HBI diatom lipids in Arctic sea ice and that IP25 is made by a relatively small proportion of sea ice diatoms. In contrast, median sterol/IP25 values were all substantially higher than those in cultures of HBI-producing diatoms, suggesting that sterols are made by the majority of sea ice diatoms. The sterol/IP25 ratio was quite variable between locations and samples, likely as a result of differences in diatom assemblage; however, a comparison of individual and median sterol/IP25 values in sea ice with those from surface sediments from different Arctic regions demonstrated that sterols from sea ice diatoms may, in some cases, have a significant impact on the sedimentary budget. This should be considered carefully for quantitative estimates of palaeo sea ice reconstruction using methods such as the PIP25 index, which are based on the relative concentrations of IP25 and sterols in Arctic marine sediment cores.

A comparative evaluation of Golgi protein-73, fucosylated hemopexin, α-fetoprotein, and PIVKA-II in the serum of patients with chronic hepatitis, cirrhosis, and hepatocellular carcinoma

Golgi protein-73 (GP73) and fucosylated proteins have been proposed as potential serum markers for liver disease and/or hepatocellular carcinoma (HCC). The purpose of this study was to compare the sensitivity and specificity of serum GP73 and fucosylated hemopexin (Fuc-HPX) with α-fetoprotein (AFP) and with protein induced by the absence of vitamin K or antagonist-II (PIVKA-II) for diagnosing chronic hepatitis, cirrhosis, and HCC. The concentration of GP73 in human sera was determined using an enzyme-linked immunosorbent assay employing mouse monoclonal and rabbit polyclonal GP73 antibodies. Fuc-HPX was detected using a lectin chemiluminescence-linked immunosorbent assay using a mouse monoclonal anti-hemopexin antibody and Aleuria aurantia lectin. A total of 229 serum samples from patients with chronic hepatitis, cirrhosis, and HCC, as well as from normal individuals were evaluated using these four markers. GP73 and Fuc-HPX showed significantly higher values in samples from patients with cirrhosis and HCC than in samples from patients with hepatitis and from normal individuals. The areas under the curves (AUCs) for GP73, Fuc-HPX, AFP, and PIVKA-II were 0.90, 0.77, 0.74, and 0.88, respectively, for liver cirrhosis and HCC samples vs. hepatitis and normal samples. The AUCs of GP73, Fuc-HPX, AFP, and PIVKA-II were 0.78, 0.72, 0.81, and 0.90, respectively, for HCC samples vs. all other samples. PIVKA-II showed superior sensitivity and specificity for HCC compared with the other three markers. GP73 may be useful for detecting cirrhosis as a risk factor for HCC. Fuc-HPX showed inferior sensitivity and specificity compared to the other markers.