14C Content Research Articles

Radiocarbon and wood anatomy as complementary tools for generating tree-ring records in Bolivia.

The science of tropical dendrochronology is now emerging in regions where tree-ring dating had previously not been considered possible. Here, we combine wood anatomical microsectioning techniques and radiocarbon analysis to produce the first tree-ring chronology with verified annual periodicity for a new dendrochronological species, Neltuma alba (commonly known as "algarrobo blanco") in the tropical Andes of Bolivia. First, we generated a preliminary chronology composed of six trees using traditional dendrochronological methods (i.e., cross-dating). We then measured the 14C content on nine selected tree rings from two samples and compared them with the Southern Hemisphere (SH) atmospheric 14C curves, covering the period of the bomb 14C peak. We find consistent offsets of 5 and 12 years, respectively, in the calendar dates initially assigned, indicating that several tree rings were missing in the sequence. In order to identify the tree-ring boundaries of the unidentified rings we investigated further by analyzing stem wood microsections to examine anatomical characteristics. These anatomical microsections revealed the presence of very narrow terminal parenchyma defining several tree-ring boundaries within the sapwood, which was not visible in sanded samples under a stereomicroscope. Such newly identified tree rings were consistent with the offsets shown by the radiocarbon analysis and allowed us to correct the calendar dates of the initial chronology. Additional radiocarbon measurements over a new batch of rings of the corrected dated samples resulted in a perfect match between the dendrochronological calendar years and the 14C dating, which is based on good agreement between the tree-ring 14C content and the SH 14C curves. Correlations with prior season precipitation and temperature reveal a strong legacy effect of climate conditions prior to the current Neltuma alba growing season. Overall, our study highlights much potential to complement traditional dendrochronology in tree species with challenging tree-ring boundaries with wood anatomical methods and 14C analyses. Taken together, these approaches confirm that Neltuma alba can be accurately dated and thereby used in climatic and ecological studies in tropical and subtropical South America.

Compositional characteristics and indication of n-fatty acids in alpine meadow plants and soils

AimTo explore the distributions and indication of n-fatty acids in the plants and soils from alpine meadow, and how n-fatty acids in plants and soils are associated. MethodsThe plant (grass, herb, and shrub) and soil samples were collected from alpine meadow in the Qinghai-Tibet Plateau, and the compositional characteristics of n-fatty acids were analyzed using GC-MS. Results and conclusionn-Fatty acids ranging from C6 to C28 were identified, C16 was the most abundant fatty acid in most plants, which contributed between 39.1% and 74.2% to total n-fatty acids; the most abundant fatty acid in soils was C15, which contributed between 72.1% and 89.1% to total n-fatty acid. The total n-fatty acid content of Artemisia hedinii and the long chain n-fatty acid content of Ajuga lupulina were the highest, while the total and long chain n-fatty acid content of Saxifraga tangutica were the lowest. The contents of C20, C22, C24 and C26 in indicative plants of degradation and typical dominant plants (Festuca sinensis, Elymus nutans, Poa crymophila, Kobresia humulis, Kobresia pygmaea) were higher than other long chain n-fatty acids (C ≥ 20). The n-fatty acids content of the plants in degraded alpine meadow were higher than that in non-degraded alpine meadow except C6, C23, C25 and C27. The total n-fatty acids content of plants and soils in degraded alpine meadow were higher than that of non-degraded meadow. The n-fatty acids content in soils were decreased with the increasing depth of sampling except C15. The positive correlation of long chain n-fatty acids content in soils and plants was strongly significant (p < 0.001, R2 = 0.926). The compositional characteristics of n-fatty acids in plants and soils were similar. Therefore, the source of the long chain n-fatty acids in the soil might be deduced from native vegetation.

Prospects for Biodiesel Production from Emerging Algal Resource: Process Optimization and Characterization of Biodiesel Properties

The present work focuses on the optimization of the energy conversion process and the use of algal resources for biodiesel production with ultrasound and microwave techniques in Oedogonium, Oscillatoria, Ulothrix, Chlorella, Cladophora, and Spirogyra for the first time. The fuel properties are investigated to optimize the efficiency of the newly emerging algal energy feedstock. The study indicates that the optimized microwave technique improves the lipid extraction efficiency in Oedogonium, Oscillatoria, Ulothrix, Chlorella, Cladophora, and Spirogyra (38.5, 34, 55, 48, 40, and 33%, respectively). Moreover, the ultrasonic technique was also effective in extracting more lipids from Oedogonium sp., Oscillatoria sp., Ulothrix sp., Chlorella, Cladophora sp., and Spirogyra sp. (32, 21, 51, 40, and 36%, respectively) than from controls, using an ultra-sonication power of 80 kHz with an 8-min extraction time. The fatty acid composition, especially the contents of C16:0 and C18:1, were also enhanced after the microwave and sonication pretreatments in algal species. Enhancement of the lipids extracted from algal species improved the cetane number, high heating value, cold filter plugging point, and oxidative stability as compared to controls. Our results indicate that the conversion of biofuels from algae could be increased by the ultrasound and microwave techniques, to develop an eco-green and sustainable environment.

Effects of Macleaya Cordata Extract on Performance, Nutrient Apparent Digestibilities, Milk Composition, and Plasma Metabolites of Dairy Goats

In this study, we aimed to investigate the effects of Macleaya cordata extract (MCE) supplementation on performance, nutrient apparent digestibilities, plasma metabolites, and milk quality in dairy goats. Twenty-four lactating Guanzhong dairy goats (n = 24) were randomly divided into two groups (each containing 12 goats) in a 52-day trial: the CON group was fed a basal diet; the MCE group was fed a basal diet supplemented with 400 mg/kg MCE. The results indicated that the 4% fat corrected milk yield (4% FCM); uncorrected milk yield; milk-fat concentration; content of C4:0, C18:0, and C18:1n9c fatty acids in milk; and apparent digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) in the MCE group were significantly higher (p < 0.05). Furthermore, the lactoferrin (LTF), alpha-lactalbumin (α-La), and beta-lactoglobulin (β-Lg) of the milk and feed conversion rate (FCR) of the goats were significantly greater (p < 0.01) in the MCE group than in the CON group. In contrast, the somatic cell count (SCC) (p < 0.01), content of C14:0 fatty acids (p < 0.01) of milk, and blood urea nitrogen (BUN) concentrations (p < 0.05) were significantly lower in the in the MCE goats. These results show that the feeding of MCE can increase the performance and apparent nutrient digestibility of fiber in dairy goats, improving the quality of goat milk.

РАСПРОСТРАНЕНИЕ УГЛЕРОДА-14 В ОКРУЖАЮЩЕЙ СРЕДЕ ПРИ НОРМАЛЬНЫХ УСЛОВИЯХ ЭКСПЛУАТАЦИИ КУРСКОЙ АЭС

Introduction: 14C is one of the fifteen radionuclides that account for at least 99 % of the radiation dose to the critical group of the population from NPP emission sources. The continuous growth of the total capacity of operating NPPs leads to a significant increase in the amount of 14С emitted into the environment during NPP operation. Efficient capture and disposal of 14C, which has a half-life of 5760 years, is a very laborious undertaking. At the same time, due to the high mobility of this radionuclide, local foci of contamination with 14C can appear both near the NPP at a distance of 1–2 km from its ventilation pipe, and in soil and plants located at a distance of 20–30 km from the NPP due to the transfer of air masses. Therefore, the control of the formation of 14C during the operation of nuclear power plants, its content in emissions and discharges of nuclear power plants, as well as distribution in the environment is an urgent problem today. Purpose: Analysis of the environmental pollution due to emissions and discharges of radiocarbon from the Kurskaya nuclear power plant. Material and methods: During the research, a method being developed by specialists of the Laboratory for Radiation Safety of Personnel was used to determine the specific activity of 14C in soil and vegetation. To explore the 14C content in the air, the method of bubbling air through a TASC-HT-HTO-C-14 flow meter-sampler (Overhoff technology, USA) and the method of air conditioning through a Ballu BDH-15L air dryer (Ballu, Russia) were used. To prepare counting samples from selected soil and food samples, a method based on the combustion of selected samples in a Pyrolyser-6 Trio catalytic decomposition system was used. All prepared counting samples, including samples from surface water and biosubstrate of the personnel of the Kursk NPP and the population, were measured by liquid scintillation spectrometry on a Tri-Carb 3180 TR/SL alpha, beta spectrometer. Results: On the basis of an integrated approach to assessing the content of 14C in air, water, soil and food, an analysis of the formation of environmental pollution due to emissions and discharges 14C from the Kurskaya NPP was carried out. Conclusions: An increased content of the 14C radionuclide in soil samples, food products and vegetation in the area of the Kursk NPP with RBMK-1000 nuclear reactors is shown, both in comparison with the content of natural 14C and NPPs operating BN-600,800 and VVER-1000 nuclear reactors. The necessity of taking into account radiocarbon emissions from NPPs into the environment in the problem of optimizing the radiation protection of the population under the conditions of normal operation of NPPs is confirmed.

Effects of Late Gestation Supplements Differing in Fatty Acid Amount and Profile to Beef Cows on Cow Performance, Steer Progeny Growth Performance through Weaning, and Relative mRNA Expression of Genes Associated with Muscle and Adipose Tissue Development.

Strategic supplementation during late gestation has the potential to alter progeny performance. Mature fall-calving Simmental × Angus cows were used to evaluate the effects of late gestation supplementation of fatty acids to beef cows on cow performance, steer progeny growth performance during pre-weaning and backgrounding periods, and relative mRNA expression of genes associated with myogenesis and adipogenesis. Cows (n = 190; 4 pasture groups of cows/treatment) grazed endophyte-infected tall fescue and were supplemented during late gestation with calcium salts of either saturated fatty acid/monounsaturated fatty acid (SFA/MUFA), polyunsaturated fatty acid (PUFA), or an isocaloric and isonitrogenous control (CON). There were no differences (p ≥ 0.11) in cow body weight (BW) or body condition scores from pre-supplementation to weaning or steer BW at birth, weaning, or at the end of the backgrounding period. Concentrations of C18:2n-6 in plasma were greater (p = 0.01) in SFA/MUFA and PUFA cows compared to CON cows during supplementation. For mRNA expression in the longissimus muscle of steer progeny from birth to weaning: PAX7 decreased to a greater (p < 0.01) extent for SFA/MUFA and PUFA steers; AGPAT1 and CPT1 increased to a greater (p ≤ 0.02) extent for CON steers. The expression of MYH7 mRNA during the pre-weaning period was greater (p = 0.01) in PUFA. In conclusion, late gestation fatty acid supplementation modified plasma relative concentrations of fatty acids for dams and progeny and modified mRNA expression of genes related to myogenesis and adipogenesis but had limited effects on progeny growth performance during pre-weaning and backgrounding periods.

Ultra small mass AMS 14C sample preparation and analyses at NIES-TERRA AMS facility

We have made substantial improvements to the NEC 5 MV tandem Pelletron AMS system, such as installing a new type of MC-SNICS ionizer, reconstructing beam lines with the development of the graphite preparation method using an online elemental analyzer for small mass samples down to 1 μgC. To obtain an adequately stable and strong beam current intensity for reliable measurement of small mass samples, we examined graphite position depths (0.35–2.0 mm) related to the optimal geometric conditions to enhance the efficiency of the iron catalyst. Our AMS system generated the most stable and intense beam current at a graphite depth of 1.5–2.0 mm and 2 mg of the iron catalyst, with ionization efficiency of 18–22 %. Under these conditions, the current produced with the 1–10 μgC samples showed a more stable beam current (10–20 μA) and a fivefold increase in beam output duration (greater than 30 min compared to 5 min at 1 μgC). Effects of small carbon graphite-induced isotopic fractionation and higher background was corrected by measuring samples relative to standards of similar mass and a blank. The pMC results were obtained for ultra-small samples ranging from 1 to 50 μgC, calculated relative to adjacent HOxII (NIST SRM 4990C) and IAEA-C1 standards of similar amounts for corrected 14C contents, were approximately in agreement with consensus values overall. By using the method developed in this study, we confirmed the 14C content of ultra-small carbon samples of (1-10 μgC) of IAEA-C8 standards can be measured with precision and accuracy of a few percent.

TRACES OF 14C EMISSIONS FOR THE OPERATION PERIOD OF TWO UKRAINIAN NPPS: RIVNE AND CHORNOBYL

ABSTRACTThe aim of this study was a comparative retrospective assessment of radiocarbon (14C) as a tracer, caused by operational emissions of Rivne and Chornobyl nuclear power plants (NPPs), which are equipped with different types of nuclear reactors. For this purpose, 14C was studied in annual tree rings of pine taken at a distance of 1.5 km southwest of the Rivne NPP and at a distance of 3.5 km west-northwest of the Chornobyl NPP, near the Yaniv railway station. As a background, we use the 14C in air data (Hua et al. 2013), which we continue for time interval 2009–2020 with our experimental data for pine tree rings. Tree rings were also collected in a rural area 60 km west of Kyiv, where industrial impact, in our opinion, is absent. 14C in wood samples was determined using the conventional method based on liquid scintillation counting. It was found that the 14C excess in the annual tree-ring samples of pine near the Chornobyl NPP during the observed operation period (1984–2000) was 3.0–13.0 pMC, except for the 1986, the year of the Chornobyl accident, when the 14C value rose sharply to 182.7 pMC (14C excess 62 pMC). After 2000, the content of 14C in the air near the Chornobyl nuclear power plant did not exceed the background values within the uncertainty of the measured data. The concentration of 14C in the samples of annual tree rings of pine near the Rivne NPP for the observation period (1986–2019) corresponded to the background levels within the uncertainty of the measured data. The study of environmental traces of 14C emissions from two NPPs equipped with different types of reactors showed significantly lower emissions of Rivne NPP with VVER compared with emissions from Chornobyl NPP with RBMK reactors.

Milk fatty acids as indicators of delayed commencement of luteal activity in dairy cows in early lactation.

Excessive mobilization of adipose reserves due to severe negative energy balance in early lactation may be detrimental to dairy cow fertility at individual and herd level. Reproductive efficiency is one of the main factors influencing herd profitability and a strategy for early detection and management of cows with delayed resumption of cyclicity will result higher conception rate, decreased proportion of cows with extended lactation, fewer inseminations per conception and lower culling rates due to reproductive disorders. Using two groups of dairy cows (Holstein n=37, Swedish Red breed [SRB] n=49), we investigated potential differences between cows with different commencement of luteal activity (CLA) and the feasibility of using milk fatty acids (MFAs) as predictors of delayed CLA. Milk samples for progesterone analysis were collected twice weekly during the first six weeks in milk. The concentrations of the MFAs C14:0, C16:0, C18:0 and C18:1 cis-9 in milk (g/100 g milk) and in milk fat (g/100 g fat) were analysed by Fourier transform infrared spectroscopy and individual MFA profiles were calculated by weeks in milk. Commencement of luteal activity was defined as the first day with milk progesterone concentrations >3ng/ml at two successive measurements. The study population was categorized as early (n=42) or late (n=44) CLA, using the median value of 21 DIM as the cut-off. Analysis of the data revealed that CLA was correlated with the proportion of some specific MFAs, where cows with delayed CLA had lower IGF-1 (92.9 ± 7.9 vs. 114.1 ± 7.9ng/ml; p=.05) and C14:0 levels (10.4 ± 0.2 vs. 11.5 ± 0.2g/100 fat; p < .01) and higher C18:0 (9.6 ± 0.2 vs. 8.9 ± 0.6g/100 fat; p < .01) and C18:1 cis-9 levels (24.9 ± 0.4 vs. 23.5 ± 0.4g/100 fat; p < .05). Delayed CLA (mean 34 days) was predictable for approximately 80% of cows based on C18:0 or C18:1 cis-9 concentrations in week 2 postpartum. Overall, MFAs (C18:0 and C18:1 cis-9) as biomarkers were better indicators than beta-hydroxybutyrate or non-esterified fatty acids in early detection of cows with delayed or normal CLA. The MFA concentrations in milk samples from cows in early lactation can thus be used as a non-invasive method to identify cows at risk of delayed CLA, acting as potential biomarkers for future reproductive performance.

Supplementation of palmitoleic acid improved piglet growth and reduced body temperature drop upon cold exposure.

Piglet survival is a major challenge in the first few days postpartum and interventions during this period may improve survival and growth. This study investigated the effects of palmitoleic acid (C16:1n-7; PA) supplementation on growth performance, body temperature, fatty acid (FA), and energy metabolism in milk-replacer-fed piglets. Forty-eight piglets were stratified by body weight and randomly assigned to one of four dietary treatments (0%, 1%, 2%, and 3% PA supplementation as a percent of milk replacer) and given the diet through an orogastric tube. They were fed dietary treatments every 2 h for 4 d in the first week postpartum and all were sacrificed at the end of the experiment. The piglets were weighed daily, and half in each dietary treatment group, the same piglets each day, were exposed daily to a lower temperature for 2 h. Plasma samples were collected immediately before sacrifice for analyses of FA and other plasma metabolites. The weight of organs and empty body weight were determined after sacrifice. Liver and semimembranosus muscle tissue samples were collected and analyzed for FA content. Contents of C16:1n-7 and C18:1n-7 in both plasma and liver (P < 0.001), and C16:1n-7 in semimembranosus muscle (P < 0.001) increased linearly as PA supplementation increased. Most plasma FA levels (except C16:1n-7, C16:1n-9, and C22:5n-3) were lower in piglets exposed to lower temperatures than those that were not. Plasma glucose, triglycerides, and lactate dehydrogenase levels increased linearly with PA supplementation (P < 0.001). Piglets' average daily gain, liver glycogen pool, liver weight, and gallbladder weight increased linearly (P < 0.05, P < 0.01, P < 0.05, and P < 0.001, respectively), but lung weight, liver nitrogen content, and body temperature drop decreased linearly (P < 0.01, P < 0.001, and P < 0.05, respectively) with PA supplementation. Piglets exposed to low temperature had greater liver nitrogen (P < 0.05) and lactate dehydrogenase (P < 0.001) contents but had lower liver weight (P < 0.01) and plasma lactate concentration (P < 0.05) than those that were not. In conclusion, this study demonstrated the importance of PA on the growth performance of the piglets by increasing their average daily gain and decreasing a drop in body temperature upon cold exposure, most likely due to a modified energy metabolism.

Channel Incision Ages to the Rescue: An Improved Age for the Penultimate Earthquake That Ruptured the Carrizo Section of the South-Central San Andreas Fault

ABSTRACT A primary step toward assessing the time and size of future earthquakes is identifying earthquake recurrence patterns in the seismic record. The San Andreas fault (SAF) is one of the most studied active faults in the world. However, there is no unequivocal interpretation of paleoseismic data to determine the timing and rupture extent of the earthquakes that occurred prior to the historical 1857 and 1906 ruptures. The penultimate earthquake is the least well-dated earthquake along the Cholame, Carrizo, and Big Bend sections of the SAF. The main reason for this poor determination is because the past few hundred years have seen large natural fluctuations in atmospheric C14 concentration. These fluctuations mean that a single radiocarbon date may yield a calibrated age consisting of several possible age ranges. At sites along frequently rupturing faults with historical ruptures, such as the SAF and the North Anatolian fault in Turkey, determining the incision age of channels displaced only by the most recent earthquake can place a tighter minimum limit on the possible age range of the penultimate earthquake. In our study, we dated five sandy fill units with the post-infrared infrared-stimulated luminescence method on single feldspar grains of channel Sieh 31 in the Carrizo Plain. The data indicate the channel Sieh 31, offset ∼6 m during the 1857 earthquake, incised before ∼1740 ± 30 C.E. (1σ). This new result trims the age constraint of the penultimate earthquake that ruptured the Carrizo section of the SAF determined at the nearby Bidart Fan site from 1640–1857 to 1631–1745 C.E., tightening the age constraint by nearly 80 yr. The revised mean recurrence interval for surface rupturing earthquakes along the Carrizo section of the south-central SAF is 117 yr (95% confidence interval 62–255 yr). This approach can improve paleoearthquake age and slip-per-earthquake constraints.

No signature of extreme solar energetic particle events in high-precision 14C data from the Alaskan tree for 1844–1876 CE

Cosmogenic nuclides – 14C from tree rings and 10Be and 36Cl from ice cores serve as an effective proxy for past extreme solar energetic particle (SEP) events. After identifying the first signature of an extreme SEP event in 774 CE, several candidates have been found in these proxy archives, such as 993 CE, 660 BCE, and 7176 BCE. Their magnitudes have been estimated to be tens of times larger than that of the largest SEP event ever observed since the 1950s. Although a detailed survey of such extreme SEP events is ongoing, the detection of intermediate-sized SEP events that bridge the gap between modern observations and extreme events detected in cosmogenic nuclides has not progressed sufficiently, primarily because of the uncertainties in cosmogenic nuclide data. In this study, we measured 14C concentrations in tree rings in the 19th century (1844–1876 CE) to search for any increases in 14C concentrations corresponding to intermediate-size extreme SEP events. We utilized Alaskan tree-ring samples cut into early and latewoods to suppress the potential seasonal variations in intra-annual 14C data. Notably, no significant 14C variations were observed between early and latewoods (0.0 ± 0.3‰), and the annual resolution 14C data series displayed an error of ~ 0.8‰. Over the entire study period, no significant increase in 14C concentrations characterized by other candidates of extreme SEP events such as the 774 CE event was detected in the annual 14C data. The present result imposes a constraint on the SEP fluence when the largest class of recorded solar storms occurred (especially those in 1859 CE and 1872 CE).

Effects of rutin supplementation on growth performance, slaughter performance, serum parameters, and meat quality of Nubian goats.

Previous studies found that rutin can improve production performance of sheep and dairy cows. However, it is not clear whether rutin has similar effects in goats. Hence, the aim of this experiment was to study the effects of rutin supplementation on growth performance, slaughter performance, serum parameters, and meat quality of Nubian goats. A total of 36 healthy Nubian ewes were randomly divided into three groups. Goats were fed the basal diet supplemented with 0 (R0), 25 (R25), and 50 (R50) mg rutin per kg of diet. The growth performance and slaughter performance of goats had no significant difference among three groups. The meat pH45min and moisture were significantly higher in the R25 group than the R50 group (p < 0.05), but the color value b* and contents of C14:0, C16:0, C18:0, C18:1n9c, C20:1, saturated fatty acid (SFA), and monounsaturated fatty acid (MSFA) in meat had an opposite outcome. The dressing percentage had an increasing tendency in the R25 group compared with the R0 group (0.05 < p < 0.10), but the shear force, water loss rate and crude protein of meat had opposite results. In conclusion, rutin could not affect the growth performance and slaughter performance of goats; low levels could possibly improve meat quality.

Production of a selective antibacterial fatty acid against Staphylococcus aureus by Bifidobacterium strains.

Aims: C16 monounsaturated fatty acid (C16:1) show antibacterial activity against Staphylococcus aureus, a pathogen associated with various diseases such as atopic dermatitis and bacteremia, while the compound does not exhibit antibacterial activity against Staphylococcus epidermidis, an epidermal commensal that inhibits the growth of S. aureus. In this study, we aimed to find bifidobacterial strains with the ability to produce C16:1 and to find a practical manner to utilize C16:1-producing strains in industry. Methods: Various Bifidobacterium strains were screened for their content of C16:1. The chemical identity of C16:1 produced by a selected strain was analyzed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). Medium components that affect the C16:1 content of the selected strain were investigated. Antibacterial activity against staphylococci was compared between the authentic C16:1 isomers and total fatty acids (TFA) extracted from the selected strain. Results: B. adolescentis 12451, B. adolescentis 12-111, B. boum JCM 1211, and Bifidobacterium sp. JCM 7042 showed high C16:1 content among the tested strains. TFA extracted from Bifidobacterium sp. JCM 7042 contained C16:1 at 2.3% as the fatty acid constituent (2.4 mg/L of broth). Through GC-MS and LC-MS analyses, the C16:1 synthesized by Bifidobacterium sp. JCM 7042 was identified as 7-cis-hexadecenoic acid (7-cis-C16:1). The authentic 7-cis-C16:1 showed strong and selective antibacterial activity against S. aureus, similar to 6-cis-C16:1, with a minimum inhibitory concentration (MIC) of < 10 µg/mL. Components that increase C16:1 productivity were not found in the MRS and TOS media; however, Tween 80 was shown to considerably reduce the C16:1 ratio in TFA. Antibacterial activity against S. aureus was observed when the TFA extracted from Bifidobacterium sp. JCM 7042 contained high level of 7-cis-C16:1 (6.1% in TFA) but not when it contained low level of 7-cis-C16:1 (0.1% in TFA). Conclusion: The fatty acid, 7-cis-C16:1, which can selectively inhibit the S. aureus growth, is accumulated in TFA of several bifidobacteria. The TFA extracted from cultured cells of Bifidobacterium sp. JCM 7042 demonstrated antibacterial activity. From a practical viewpoint, our findings are important for developing an efficient method to produce novel skin care cosmetics, functional dairy foods, and other commodities.

Determination of Radiocarbon Content in Bio-Oil Samples by Mini Carbon Dating System in the Gliwice Radiocarbon and Mass Spectrometry Laboratory

Abstract The applications of isotopes are used by many European countries to investigate environmental changes. A compact modern accelerator mass spectrometry (AMS) system known as Mini Carbon Dating System (MICADAS) is used in Gliwice Radiocarbon and Mass Spectrometry Laboratory for determining the 14C content in different environmental samples including liquid fuels. For radiocarbon measurement using MICADAS, the liquid samples are accurately prepared using the tin capsules for liquids for combustion in elemental analyser (EA) and graphitisation in the AGE system. In this study, the determination of 14C content in three different bio-oil samples and one reference sample of 100% biomass was conducted. Bio-oil samples were prepared using tin capsules for liquids sealed in the second capsules for solids to avoid sample evaporation while the reference sample was prepared using the tin capsule for solids for combustion in EA and graphitisation in the AGE system. Based on the 14C measurement results, one of the bio-oils was not produced from the analysed reference biomass. Two others were determined as a mixture of bio- and fossil components, and based on 14C the bio-carbon content was calculated. For all samples, the 14C measurement showed reproducible and reliable results.

Ceramides in peripheral arterial plaque lead to endothelial cell dysfunction

BackgroundPeripheral arterial atheroprogression is increasingly prevalent, and is a risk factor for major limb amputations in individuals with risk factors such as diabetes. We previously demonstrated that bioactive lipids are significantly altered in arterial tissue of individuals with diabetes and advanced peripheral arterial disease. MethodsHere we evaluated whether sphingolipid ceramide 18:1/16:0 (C16) is a cellular regulator in endothelial cells and peripheral tibial arterial tissue in individuals with diabetes. ResultsWe observed that C16 is the single most elevated ceramide in peripheral arterial tissue from below the knee in individuals with diabetes (11% increase, P < .05). C16 content in tibial arterial tissue positively correlates with sphingomyelin (SPM) content in patients with and without diabetes (r2 = 0.5, P < .005; r2 = 0.17, P < .05; respectively). Tibial arteries of individuals with diabetes demonstrated no difference in CERS6 expression (encoding ceramide synthase 6; the predominate ceramide synthesis enzyme), but higher SMPD expression (encoding sphingomyelin phosphodiesterase that catalyzes ceramide synthesis from sphingomyelins; P < .05). SMPD4, but not SMPD2, was particularly elevated in maximally diseased (Max) tibial arterial segments (P < .05). In vitro, exogenous C16 caused endothelial cells (HUVECs) to have decreased proliferation (P < .03), increased apoptosis (P < .003), and decreased autophagy (P < .008). Selective knockdown of SMPD2 and SMPD4 decreased native production of C16 (P < .01 and P < .001, respectively), but only knockdown of SMPD4 rescued cellular proliferation (P < .005) following exogenous supplementation with C16. ConclusionsOur findings suggest that C16 is a tissue biomarker for peripheral arterial disease severity in the setting of diabetes, and can impact endothelial cell viability and function. Clinical relevancePeripheral arterial disease and its end-stage manifestation known as chronic limb-threatening ischemia (CLTI) represent ongoing prevalent and intricate medical challenges. Individuals with diabetes have a heightened risk of developing CLTI and experiencing its complications, including wounds, ulcers, and major amputations. In the present study, we conducted a comprehensive examination of the molecular lipid composition within arterial segments from individuals with CLTI, and with and without diabetes. Our investigations unveiled a striking revelation: the sphingolipid ceramide 18:1/16:0 emerged as the predominant ceramide species that was significantly elevated in the peripheral arterial intima below the knee in patients with diabetes. Moreover, this heightened ceramide presence is associated with a marked impairment of endothelial cell function and viability. Additionally, our study revealed a concurrent elevation in the expression of sphingomyelin phosphodiesterases, enzymes responsible for catalyzing ceramide synthesis from sphingomyelins, within maximally diseased arterial segments. These findings underscore the pivotal role of ceramides and their biosynthesis enzymes in the context of CLTI, offering new insights into potential therapeutic avenues for managing this challenging disease process.

Technical Carbon Black and Green Technology

Abstract Carbon black (CB) is produced through the incomplete combustion of biomass or thermal decomposition in an oxygen-deprived environment. Technical carbon black (TCB) primarily consists of elemental carbon and comes in various grades distinguished by surface area and nanostructure morphologies. However, TCB production raises sustainability concerns due to its reliance on non-renewable feedstock, significant CO2 emissions and high energy consumption. TCBs find extensive use as reinforcing fillers in the tire and rubber industries. Recent studies underscore the importance of eco-friendly alternatives. This research was carried out to monitor the renewability of the TCB samples by determining the 14C isotope concentration. Liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS) radiocarbon techniques were employed for measuring the 14C isotope concentration, while isotope ratio mass spectrometry (IRMS) corrected standardised isotope fractionation correction. The investigation revealed that the examined TCB samples contain extremely low 14C concentrations, measuring &lt;1 per cent modern carbon (pMC). This finding raises concerns regarding potential environmental ramifications.

Non‐Steady‐State 14C‐10Be and Transient Hillslope Dynamics in Steep High Mountain Catchments

AbstractPaired in situ cosmogenic nuclides 14C and 10Be present an opportunity to explore erosion rate disequilibria over Holocene to latest Pleistocene timescales and are a new avenue in surface processes research. 14C and 10Be concentrations in quartz from river sand collected at the outlets of five mountainous catchments in the Argentine Andes are compared in this study. River gauge and 10Be‐derived erosion rates are in good agreement; however, 14C concentrations are approximately 2.7–4 times lower than expected relative to 10Be under steady‐state erosion. Low 14C to 10Be ratios imply that sediment eroded from the high mountains was shielded for at least 7–15 ky. Neoglacial advances and storage in terraces may account for some of the reduced 14C concentrations but are insufficient alone. Transient storage in dynamic talus slopes in the steep topography of the High Andes provides the best explanation for the observed 14C concentrations.

Effects of dietary oil sources and fat extraction methods on apparent and standardized ileal digestibility of fat and fatty acids in growing pigs

BackgroundThere is a lack of data for the standardized ileal digestibility (SID) of fat and fatty acids in national feed databases. In addition, it is important to specify the procedures used for fat analyses. Therefore, an experiment was conducted to 1) determine the apparent ileal digestibility (AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition; and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.MethodsTwenty-two barrows (initial body weight: 32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum, and allotted to 1 of 11 experimental diets in a 4-period Youden Square design. A fat-free diet was formulated using cornstarch, soy protein isolate and sucrose. Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch. All diets contained 26% sugar beet pulp and 0.40% chromic oxide.ResultsThe endogenous loss of ether extract (EE) was lower than that of acid-hydrolyzed fat (AEE; P < 0.01). There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources (P < 0.05). The SID of AEE for palm oil was lower than that of sunflower oil, corn oil, canola oil, rice oil and flaxseed oil (P < 0.01). The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%. Although the AID of EE was greater than that of AEE (P < 0.01), there was no significant difference in SID of EE and AEE except for palm oil. The ratio of unsaturated to saturated fatty acids (U/S) had a positive correlation with SID of fat (P < 0.05), whereas C16:0 and long chain saturated fatty acids (LSFA) were significant negatively correlated with SID of fat (P < 0.01). The best-fit equation to predict SID of fat was SID AEE = 102.75 − 0.15 × LSFA − 0.74 × C18:0 − 0.03 × C18:1 (Adjusted coefficient of determination = 0.88, P < 0.01).ConclusionsWhen calculating the SID of fat, the EE content of the samples can be analyzed using the direct extraction method, whereas the acid hydrolysis procedure should be used to determine the AID of fat. Fat digestibility of dietary oils was affected by their fatty acid composition, especially by the contents of C16:0, LSFA and U/S.

Estimation of groundwater residence time with deeply-derived carbon mixture considered in California

Groundwater has experienced long-term overdraft due to drought and human activities in California, resulting in issues of land subsidence and groundwater anthropogenic contamination. As a useful indicator of groundwater renewal rate and its residence time, groundwater age has been conventionally investigated based on 14C content and 3H concentration. However, the influence of deeply-derived (endogenic) CO2 mixture is not fully and quantitatively considered, although endogenic carbon contributes a large part of the dissolved inorganic carbon in groundwater. Combined with 3H concentration, both conventional and modified 14C-dating methods with endogenic CO2 mixture considered are employed for groundwater age determination in California. On average, the conventional groundwater 14C apparent age is overestimated by ~4.9 kyr or ~26.2 %, causing groundwater recharge rate underestimation and aquifer recovery time overestimation by ~46.0 % and ~26.2 %, respectively. High 3H concentration indicates modern water mixture in more than one fifth of groundwater samples, including those with high modified 14C apparent age (> 12 kyr, i.e., fossil groundwater) in the Central Valley and southern California, which are generally considered not to be recharged by modern water. Modern water mixture in old groundwater can potentially bring anthropogenic contamination to these groundwater resources, which should be paid attentions by the government and the managers. The results have important implications in evaluation of groundwater replenishment and its susceptibility to modern contamination in California, and in groundwater resources estimation globally.