Ion Counting Research Articles

Management of hypocalcemia in a person with hungry bone syndrome post parathyroidectomy due to parathyroid carcinoma: a case report

Introduction: Hungry Bone Syndrome (HBS) refers to a condition in the form of prolonged and severe hypocalcemia accompanied by hypophosphatemia and hypomagnesemia that occurs after parathyroidectomy. The sudden cessation of PTH production leads to increased bone re-mineralization and a rapid shift of calcium from circulation to bone. This case report aims to present our management of hypocalcemia in a person with HBS after he underwent parathyroidectomy surgery due to parathyroid carcinoma. Case Presentation: Mr. S, 46 years old, had a total thyroidectomy and a total parathyroidectomy on April 30th, 2019, due to parathyroid carcinoma, which the patient previously had. The patient was planned for surgery because of pathological fractures in the patient's hands and feet, which were complications of parathyroid carcinoma. The laboratory examination on the first postoperative day, May 1st, 2019, obtained a total calcium of 8.2 mg/dL. On May 5th, 2019 (day 5), total calcium decreased to 6.1 mg/dL. On May 10th, 2019 (day 10), hypophosphatemia was also found with a value of 2.1 mg/dL and hypomagnesemia of 1.2 mg/dL. When experiencing complaints, the patient's calcium was monitored regularly, low calcium was found, and symptoms of hypocalcemia were also found, so this patient was given drip calcium gluconate 1000 mg every 8 hours in 100 ml normal saline. Calcium checks are carried out every 24 hours; calcium is still low for over 3 days. In addition, he was given calcitriol 2x0.25 mcg titrated up to 2x0.5 mcg, drip 40% MgSO4 in 500 salines in 24 hours, and 4x200 oral phosphate. During the treatment, the patient's calcium reached 8.2 mg/dL with albumin 3.3 g/dL with a calcium ion count of 8.4 mg/dL after 17 days of treatment. Conclusion: HBS was found due to total parathyroidectomy as the main therapy for parathyroid carcinoma. Close calcium monitoring and early administration of postoperative calcium are needed to avoid complications from hypocalcemia. Avoiding HBS can reduce the number of days in the hospital, thereby saving costs and improving the patient's quality of life.

Discriminant Analysis of Gentiana Headspace Gas Chromatography – Mass Spectrometry Extract Data from In Vitro Cultures

Abstract A set of Gentiana L. species was successfully grown in vitro under the same conditions, and 72 samples from various cultures of these species (root, shoot, cotyledon callus, hypocotyl callus, and root callus) were obtained. The investigated species were G. affinis, G. andrewsii, G. bhutanica, G. burseri, G. cachemirica, G. capitata, G. crassicaulis, G. dahurica, G. decumbens, G. freyniana, G. frigida, G. gelida, G. grossheimii, G. kurroo, G. macrophylla, G. paradoxa, G. robusta, G. scabra, G. septemfida, G. siphonantha, and G. tianschanica. The obtained samples were extracted with a methanol-acetone-water (3:1:1) mixture, evaporated to dryness, and subjected to thin layer chromatography (TLC) on silica gel in sandwich mode with ethyl acetate-methanol-water (8:2:2) as the mobile phase. The resulting dry extracts were subjected to gas chromatography – mass spectrometry (GC-MS) fingerprinting of the headspace volatile fraction. Total ion count and average mass spectrum vectors were collected as two blocks and scaled independently to form a complex dataset. The major direction separating root or shoot samples from callus samples was found not to be fully associated with the highest variance as this information was placed in the first and fourth principal components of the principal component analysis (PCA). Therefore, linear discriminant analysis was performed on the first four (only the informative) components to reveal features responsible for the separation of culture types in the multivariate space.

Charged particle diagnostics for inertial confinement fusion and high-energy-density physics experiments.

MeV-range ions generated in inertial confinement fusion (ICF) and high-energy-density physics experiments carry a wealth of information, including fusion reaction yield, rate, and spatial emission profile; implosion areal density; electron temperature and mix; and electric and magnetic fields. Here, the principles of how this information is obtained from data and the charged particle diagnostic suite currently available at the major US ICF facilities for making the measurements are reviewed. Time-integrating instruments using image plate, radiochromic film, and/or CR-39 detectors in different configurations for ion counting, spectroscopy, or emission profile measurements are described, along with time-resolving detectors using chemical vapor deposited diamonds coupled to oscilloscopes or scintillators coupled to streak cameras for measuring the timing of ion emission. A brief description of charged-particle radiography setups for probing subject plasma experiments is also given. The goal of the paper is to provide the reader with a broad overview of available capabilities, with reference to resources where more detailed information can be found.

Insights on film growth conditions on a floating substrate during reactive Ar/O2 bipolar high power impulse magnetron sputter deposition

We report several effects found in reactive bipolar high-power impulse magnetron sputtering (abbreviated as bipolar HiPIMS or BPH) discharges at the substrate level. The role of the negative peak current and the positive pulse voltage, U, on the deposition flux at the electrically insulating substrate is discussed and the results are compared to conventional DC discharges. In particular, the normalized energy flux, ϕ n , delivered to the substrate is found higher under BPH conditions at U = +300 V ( eV·nm−3) as compared to the HiPIMS ( eV·nm−3) and DCMS ( eV·nm−3) regimes which is assumed to be provoked by an intensification of the positive ion bombardment. Accordingly, the mean energy and the count of positively charged metal and gaseous ions increase in line with U as measured by energy-resolved mass spectrometry. Contrariwise, our analysis has shown a significant decrease (≈20 %) of negative oxygen ion count under BPH conditions.

The impact of dimensionality reduction of ion counts distributions on preserving moments, with applications to data compression

The field of space physics has a long history of utilizing dimensionality reduction methods to distill data, including but not limited to spherical harmonics, the Fourier Transform, and the wavelet transform. Here, we present a technique for performing dimensionality reduction on ion counts distributions from the Multiscale Mission/Fast Plasma Investigation (MMS/FPI) instrument using a data-adaptive method powered by neural networks. This has applications to both feeding low-dimensional parameterizations of the counts distributions into other machine learning algorithms, and the problem of data compression to reduce transmission volume for space missions. The algorithm presented here is lossy, and in this work, we present the technique of validating the reconstruction performance with calculated plasma moments under the argument that preserving the moments also preserves fluid-level physics, and in turn a degree of scientific validity. The method presented here is an improvement over other lossy compressions in loss-tolerant scenarios like the Multiscale Mission/Fast Plasma Investigation Fast Survey or in non-research space weather applications.

Advantages of using biologically generated 13C-labelled multiple internal standards for stable isotope-assisted LC-MS-based lipidomics.

In comprehensive lipidomics studies, accurate quantification is essential but biological and/or clinical relevance is often hindered due to unwanted variations such as lipid degradation during sample preparation, matrix effects and non-linear responses of analytical instruments. In addition, the wide chemical diversity of lipids can complicate the accurate identification of individual lipids. These analytical limitations can potentially be corrected efficiently by the use of lipid-specific isotopically labelled internal standards (IS) but currently such IS mixtures have limited coverage of the mammalian lipidome. In this study, an in vivo13C labelling strategy was employed to explore four species (Escherichia coli, Arthrospira platensis, Saccharomyces cerevisiae and Pichia pastoris) as a source of 13C-labelled internal standards (13C-ISs) for more accurate and quantitative liquid chromatography (LC)-mass spectrometry (MS)-based lipidomics. Results showed that extracts from 13C-labelled P. pastoris and S. cerevisiae contain the highest percentage of uniformly labelled lipids (both 83% compared to 67% and 69% in A. platensis and E. coli, respectively) and 13C-labelled P. pastoris extract was identified as the optimum source of 13C-ISs for comprehensive data normalisation to correct unwanted variations during sample preparation and LC-MS analysis. Overall, use of a biologically generated 13C-IS lipid mixture of 357 identified lipid ions resulted in significant reduction in the lipid CV% of normalisation compared with other normalisation methods using total ion counts or a commercially available deuterated internal standard mixture. This improved normalisation using 13C-IS was confirmed in a typical lipidomics analysis using a large number of samples (>100+) and long analysis time (>70 h). This study highlights the benefit of an in vivo labelling strategy for reducing technical and analytical variations introduced during sample preparation and analysis in lipidomics studies.

Phytochemical Composition, Antioxidant and Antiproliferative Activities of Citrus hystrix, Citrus limon, Citrus pyriformis, and Citrus microcarpa Leaf Essential Oils against Human Cervical Cancer Cell Line

The essential oil derived from Citrus plants has long been used for medicinal purposes, due to its broad spectrum of therapeutic characteristics. To date, approximately 162 Citrus species have been identified, and many investigational studies have been conducted to explore the pharmacological potential of Citrus spp. oils. This study investigated the volatile constituents of essential oil distilled from the leaves of C. hystrix, C. limon, C. pyriformis, and C. microcarpa, using gas chromatography-quadrupole mass spectrometry. A total of 80 secondary compounds were tentatively identified, representing 84.88-97.99% of the total ion count and mainly comprising monoterpene (5.20-76.15%) and sesquiterpene (1.36-27.14%) hydrocarbons, oxygenated monoterpenes (3.91-89.52%) and sesquiterpenes (0.21-38.87%), and other minor chemical classes (0.10-0.52%). In particular, 27 compounds (1.19-39.06%) were detected across all Citrus species. Principal component analysis of the identified phytoconstituents and their relative quantities enabled differentiation of the Citrus leaf oils according to their species, with the loading variables contributing to these metabolic differences being identified. The Citrus leaf oils were tested for their antioxidant and antiproliferative activities using 2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. The results indicated that C. limon displayed the highest DPPH radical scavenging ability (IC50 value of 29.14 ± 1.97 mg/mL), while C. hystrix exhibited the lowest activity (IC50 value of 279.03 ± 10.37 mg/mL). On the other hand, all the Citrus oils exhibit potent antiproliferative activities against the HeLa cervical cancer cell line, with IC50 values of 11.66 μg/mL (C. limon), 20.41 μg/mL (C. microcarpa), 25.91 μg/mL (C. hystrix), and 87.17 μg/mL (C. pyriformis).

Chemical ionization mass spectrometry utilizing ammonium ions (NH4+ CIMS) for measurements of organic compounds in the atmosphere

Abstract. We describe the characterization and field deployment of chemical ionization mass spectrometry (CIMS) using a recently developed focusing ion-molecule reactor (FIMR) and ammonium–water cluster (NH4+⋅H2O) as the reagent ion (denoted as NH4+ CIMS). We show that NH4+⋅H2O is a highly versatile reagent ion for measurements of a wide range of oxygenated organic compounds. The major product ion is the cluster with NH4+ produced via ligand-switching reactions. Other product ions (e.g., protonated ion, cluster ion with NH4+⋅H2O, with H3O+, and with H3O+⋅H2O) are also produced, but with minor fractions for most of the oxygenated compounds studied here. The instrument sensitivities (ion counts per second per part per billion by volume, cps ppbv−1) and product distributions are strongly dependent on the instrument operating conditions, including the ratio of ammonia (NH3) and H2O flows and the drift voltages, which should be carefully selected to ensure NH4+⋅H2O as the predominant reagent ion and to optimize sensitivities. For monofunctional analytes, the NH4+⋅H2O chemistry exhibits high sensitivity (i.e., >1000 cps ppbv−1) to ketones, moderate sensitivity (i.e., between 100 and 1000 cps ppbv−1) to aldehydes, alcohols, organic acids, and monoterpenes, low sensitivity (i.e., between 10 and 100 cps ppbv−1) to isoprene and C1 and C2 organics, and negligible sensitivity (i.e., <10 cps ppbv−1) to reduced aromatics. The instrumental sensitivities of analytes depend on the binding energy of the analyte–NH4+ cluster, which can be estimated using voltage scanning. This offers the possibility to constrain the sensitivity of analytes for which no calibration standards exist. This instrument was deployed in the RECAP campaign (Re-Evaluating the Chemistry of Air Pollutants in California) in Pasadena, California, during summer 2021. Measurement comparisons against co-located mass spectrometers show that the NH4+ CIMS is capable of detecting compounds from a wide range of chemical classes. The NH4+ CIMS is valuable for quantification of oxygenated volatile organic compounds (VOCs) and is complementary to existing chemical ionization schemes.

An Enclosed Plant Terrarium is a Renewable Source of an Aqueous f\ Form of Hybrid-Plasma

Introduction: In previous reports we described a newly discovered non-thermal plasma formed without input of external energy. Moreover, this Hybrid- plasma consisted of the gas/water combination. In the present study we used the gaseous form to produce a mainly aqueous Hybrid-plasma. Methods: A dehumidifier was activated and placed in a sealed plastic container holding twelve broad leaf plants in which maximum levels of ion counts and humidity had been registered indicative of the presence of Hybrid-plasma gas. After 24 hours, the device was removed and 100-125 cc of water was collected. When the ion counts and humidity returned, to initial levels in the plant container the water extraction process was repeated (n=7). Protocol 1: Cut flowers of pink carnations were obtained from a local garden center. Two beakers were filled with either 150 cc of distilled water or dehumidified water. Branches with buds starting to flower were photographed daily for 10 days. Protocol 2: Distilled water, 150 cc was placed in snap cover plastic containers (n=5). Another set of 5 were similarly filled with the dehumidified water. Both sets were instrumented with hygrometers. Results: After dehumidifying, the percent changes of the ion count and humidity values from starting levels averaged 36% and 41%, in the enclosed plant terrarium respectively. After 24 hours the ion count was restored to maximum levels and humidity registered close to 90% after 7 iterations. After 10 days the bud in tap water had blossomed into a full grown flower, buds in Hybrid-water was essentially the same as at the start of the study. After 24hours humidity in all plastic containers with dehumidified water registered 99% whereas the humidity in the distilled water containers ranged from 89-92%. Conclusions: The aqueous form of Hybrid-plasma can be extracted from a gaseous form by using a dehumidifier. Flower buds grown in Hybrid-water fail to bloom whereas those in tap water blossomed over the same time period. Placed in a sealed container, Hybrid water uniformly registered maximum levels (99%, n=7); Distilled water values ranged from 89-92%.

Influence of the Type of Binder Used in the Treatment of Cotton Fabric with Montmorillonite Particles on the Release of Negative Ions.

Throughout history, mineral clays have had a multitude of applications. With recent developments in the textile industry, they have been used for their antimicrobial properties. As a promising phyllosilicate with a negative layer charge, montmorillonite (MMT) was used in this work to treat cotton fabric to evaluate its ability to generate negative air ions (NAIs). The MMT was dispersed with varying binder concentrations. Resins of different composition (polyurethane or acrylic) was applied to cotton fabric by padding, and the negative ion count was measured. Two types of MMT with different characteristics were tested. Electronic microscopy (SEM) was used to study the presence of MMT particles on the cotton fabric surface, and the colors of the samples were tested. It was observed that the composition of the binder used had a significant influence on the number of negative ions released by the treated sample.

226 Proteomic and Metabolomic Profiles are Associated with Fresh Pork Loin Quality Phenotypes

Abstract The objective was to define proteomic and metabolomic profiles associated with premium and poor-quality pork. Fresh pork loins (n=100) were aged 12 to 14 d postmortem before quality evaluation. Chops with a star probe values less than 4.5 kg, and a Hunter L score less than 47 were categorized as Premium (n=10). Chops with star probe values greater than 5.7 kg and Hunter L greater than 49.7 were categorized as Poor (n=10). Proteins soluble in low ionic strength buffer (50 mM Tris-HCl pH 8.5 and 1 mM EDTA) were extracted, digested with trypsin, and labeled with 11-plex isobaric TMT labels. Peptides were introduced to the Q-Exactive Hybrid Quadrupole-Orbitrap Mass Spectrometer and identified and quantified with Proteome Discoverer. Data were normalized to the total ion count from each run, Log2 transformed, and median normalization was performed. Only proteins identified in at least one-half of the samples containing at least two unique peptides were included in the analysis. Non-targeted metabolomic analyses were conducted on extracts (80% methanol) of each sample. Separation was conducted with a TG-5MS column (Thermo Scientific, 30m x 0.25mm x 0.25mm). Masses between 50-620 m/z were scanned at four scans/sec after electron impact ionization operating at 70eV. All data were analyzed in R 4.1.1 using the limma package with a false discovery rate of 0.05. Poor chops contained more sugars, including glucose, glucose-6-phosphate, fructose, and galactose. Premium chops had more amino acids, including leucine, isoleucine, serine, and methionine. Proteins/peptides in greater abundance in the soluble fraction in the Premium chops (n=24 proteins) included titin, filamin, phosphoglycerate mutase, AMP deaminase, heat shock protein 27, and calcium transporting ATPase. Proteins/peptides in greater proportion in the Poor chops (n=12 proteins) included annexin, adenylate kinase, and Maillard deglycase. The results demonstrate that distinct molecular phenotypes are associated with variation in fresh pork quality.

Mass spectrometric measurements of ambient ions and estimation of gaseous sulfuric acid in the free troposphere and lowermost stratosphere during the CAFE-EU/BLUESKY campaign

Abstract. Ambient ions play an important role in atmospheric processes such as ion-induced new particle formation. While there are several studies of ambient ions for different layers of the atmosphere, data coverage for the free troposphere and especially the upper troposphere and lower stratosphere (UTLS) region is scarce. Here, we present the first airborne measurements of ambient ions using a high-resolution atmospheric pressure interface time-of-flight mass spectrometer (HR-APi-TOF-MS) in the free troposphere and lower stratosphere above Europe on board the HALO aircraft during the CAFE-EU/BLUESKY campaign in May and June 2020. In negative measurement mode, we observed nitrate and hydrogen sulfate and their related ion clusters in an altitude range of 4.7 to 13.4 km. The horizontal profiles for those ions reveal an increasing count rate for NO3- and (HNO3)NO3- towards higher altitudes but no significant trend for HSO4−. From the count rates of the nitrate (NO3-) and hydrogen sulfate (HSO4-) core ions, we inferred the number concentration of gaseous sulfuric acid. The lowest average value was found to be 1.9×105 cm−3 at the maximum altitude bin, i.e. 13.4 km. The highest average value of 7.8×105 cm−3 was observed in the 8.7–9.2 km altitude bin. During the transit through a mixed-phase cloud, we observed an event of enhanced ion count rates and aerosol particle concentrations that can largely be assigned to nitrate ions and particles, respectively; this may have been caused by the shattering of liquid cloud droplets on the surface of the aircraft or the inlet. Furthermore, we report the proof of principle for the measurement of ambient cations and the identification of protonated pyridine.

Intercalibration of the Servicio Nacional de Geología y Minería (SERNAGEOMIN), Chile and WiscAr 40Ar/39Ar laboratories for Quaternary dating

Accurate and precise dating of Quaternary lavas and pyroclastic flow or fall deposits is essential for understanding the evolution of active volcanoes and providing context for future eruptions and hazard assessment. The 40 Ar/ 39 Ar method is commonly employed to date these volcanic materials, however, dating young (<150 ka) K 2 O-poor materials can be challenging owing to low radiogenic 40 Ar* contents that can be difficult to distinguish from trapped atmospheric argon. To address this challenge, a collaborative intercalibration exercise involving the University of Wisconsin-Madison WiscAr Laboratory and the 40 Ar/ 39 Ar Laboratory of the Servicio Nacional de Geología y Minería (SERNAGEOMIN), Chile was conducted on a common set of samples with the aim of refining our methods and optimizing precision and accuracy of age determinations. Groundmass and plagioclase samples were analyzed on a 5-collector Noblesse ion counting mass spectrometer in the WiscAr lab, whereas measurements in the SERNAGEOMIN lab were performed using an ARGUS VI spectrometer equipped with faraday detectors and one compact discrete dynode electron multiplier. Samples for the intercalibration were collected jointly from three Andean Southern Volcanic Zone volcanoes to evaluate the capability of each laboratory to date different materials. Samples from lava flows with 1.0–3.2 wt % K 2 O from Planchon-Peteroa volcanic complex and with <1.0 wt % K 2 O from Calbuco Volcano that are the focus of ongoing geological studies were measured in both laboratories. Single crystals of plagioclase (0.6–1.0 wt% K 2 O) were measured from the voluminous Diamante (Pudahuel) ignimbrite sourced from the Diamante Caldera. Multiple rounds of experiments were conducted including co-irradiation of samples at Oregon State University, as well as irradiations using the CCHEN reactor in Chile to investigate differences in neutron fluence parameters. As a result, SERNAGEOMIN has modified long-used protocols for the CCHEN reactor so that Quaternary samples may be irradiated for periods of time most appropriate for their age. Although less precise than plateau ages, the isochron ages generated in the two laboratories agree at 2σ for each sample. Six of six co-irradiated samples from Planchon-Peteroa yield plateau ages that also show inter-lab agreement at 2σ. The low K 2 O lavas from Calbuco proved more challenging with only three out of five plateau ages in agreement between labs. SERNAGEOMIN blanks were higher and more variable in Calbuco experiments, thus, differences in the variability of the measured 36 Ar blanks between the two laboratories may explain the discrepancy in plateau ages. Analysis of single plagioclase crystals from the Diamante Ignimbrite show excellent agreement between labs for both weighted mean apparent ages and isochron ages. We favor an isochron age for the ignimbrite of 132.4 ± 2.2 ka, however, discrepancies in results between samples from three different outcrops present an interesting geochronologic problem that warrants further study. Overall, the consistency of the results between labs is promising. These new precise age determinations significantly improve our understanding of the temporal evolution of these active volcanoes. • Broad agreement of ages from tephras and lavas measured in two labs. • 40 Ar/ 39 Ar dating of low K 2 O lavas from Calbuco is challenging due to limited 40 Ar*. • We favor an isochron age of ∼132 ± 2 ka ka for the 270 km 3 Diamante Ignimbrite. • Care in sample preparation and irradiation, and control of blanks are essential.

Prolonged Fasting Alters the Size, Function, and Glycoproteomic Profile of HDL Particles

ObjectivesTo investigate the effects of a single 36-hour fast on HDL glycoproteomic composition on isolated HDL particles. MethodsWe obtained plasma from a previous study where 20 healthy subjects, age 20–40, fasted for 36 hours. HDL was isolated using density-based ultracentrifugation steps, followed by size-exclusion chromatography. Glycoproteomic was analyzed using a targeted LC-MS/MS method, and lipoprotein particle size distribution analysis using nuclear magnetic resonance (NMR) spectroscopy. ResultsHDL-associated apolipoprotein A-IV (ApoA-IV) content was significantly reduced (8918.39 +/– 3823.39 normalized ion counts vs 3690.82 +/– 2147.29 normalized ion count, p adjusted < 0.0001), suggesting a reduction in intestinally-derived HDL after a 36-hour fast. HDL associated apolipoprotein C-III (ApoC-III) di-sialylated glycopeptides decreased in HDL following a 36-hour fast compared to an overnight 12-hour fast (0.1680 +/– 0.0342 normalized ion counts vs 0.1315 +/– 0.0373 normalized ion counts, p adjusted = 0.041). Additionally, particle size distribution analysis showed an increase in abundance of calibrated large HDL of size 9.6–13nm (3.42 +/– 2.218 μmol/L vs 3.885 +/– 2.134 μmol/L, p adjusted = 0.011) and a decrease in abundance of medium HDL of size 8.1–9.5nm (6.88 +/– 1.86 μmol/L vs 5.82 +/– 2.048 μmol/L, p adjusted = 0.019) after a 36-hour fast. There were no significant changes in LDL particle size (21.115 +/– nm s 21.205 +/– 0.458 nm, p adjusted = 0.655) but there was a significant increase in overall calibrated LDL particle concentration (1138.05 +/– 357.94 μmol/L vs 1262.3 +/– 313.33 μmol/L, p adjusted = 0.011) and calibrated small LDL particle concentration (454.85 +/– 187.76 μmol/L vs 598.8 +/– 190.84 μmol/L, p adjusted = 0.025). ConclusionsOur findings indicate that prolonged fasting alters lipoprotein profiles by affecting the proportions of large and small HDL and LDL particles, as well as altering the protein composition of HDL particles, specifically by reducing the abundance of ApoA-IV, which suggests a reduction in the contribution of intestinally-derived HDL particles to the circulating HDL pool. Future studies are needed to determine the long-term effects of multiple bouts of prolonged fasting. Funding SourcesUniversity of California Davis, National Institute on Aging.

Phytochemical Constituents and Antiproliferative Activities of Essential Oils from Four Varieties of Malaysian Zingiber officinale Roscoe against Human Cervical Cancer Cell Line.

This study evaluates the volatile metabolic constituents and anticancer potential of essential oils distilled from the rhizomes of four Malaysian Zingiber officinale Roscoe (Zingiberaceae family) varieties (Bentong (BE), Cameron Highlands (CH), Sabah (SA), and Bara (BA)). The ginger essential oils were analyzed by gas chromatography coupled with quadrupole mass spectrometry (GC qMS). A total of 58 secondary compounds were tentatively identified, representing 82.6–87.4% of the total ion count. These metabolites comprise mainly of monoterpene hydrocarbons (19.7–25.5%), oxygenated monoterpenes (23.6–33.7%), sesquiterpene hydrocarbons (21.3–35.6%), oxygenated sesquiterpenes (1.5–3.9%), and other minor classes of compounds (0.7–2.7%). Principal component analysis (PCA) enabled differentiation of the analyzed ginger essential oils according to their varieties, with respect to their metabolites and relative quantities. The antiproliferative activity against the HeLa cervical cancer cell line was investigated via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The oils were found to exhibit strong antiproliferative activities with IC50 values of 23.8, 35.3, 41.3, and 42.5 μg/mL for BA, BE, SA, and CH, respectively. These findings suggest that the differences among the secondary metabolites and their abundance in different varieties of Z. officinale essential oils appear to be related to their antiproliferative potential. The strong antiproliferative effects of these oils signified their potential in the prevention and chemotherapy of cervical carcinoma treatment.

Secondary ion mass spectrometer analyses for trace elements in glass standards using variably charged silicon ions for normalization

AbstractTrace element analyses of silicate materials by secondary ion mass spectrometry (SIMS) typically normalize the secondary ion count rate for the isotopes of interest to the count rate for one of the silicon isotopes. While the great majority of SIMS analyses use the signal from Si+, some laboratories have used a multiply charged ion (Si2+ or Si3+). We collected data and constructed calibration curves for lithium, beryllium, and boron using these different normalizing species on synthetic basaltic glass and soda-lime silicate glass standards. The calibrations showed little effect of changing matrix when Si+ was used, but larger effects (up to a factor of ~2) when using Si2+ or Si3+ are a warning that care must be taken to avoid inaccurate analyses. The smallest matrix effects were observed at maximum transmission compared to detecting ions with a few tens of eV of initial kinetic energy (“conventional energy filtering”). Normalizing the light element ion intensities to Al3+ showed a smaller matrix effect than multiply-charged Si ions. When normalized to 16O+ (which includes oxygen from the sample and from the primary beam), the two matrices showed distinct calibration curves, suggesting that changing sputter yields (atoms ejected per primary atom impact) may play a role in the probability of producing multiply charged silicon ions.

Miniature time-of-flight mass analyzer for use in combination with a compact highly-repetitive femtosecond laser ionization source

In most cases, a molecular ion is observed in femtosecond laser ionization mass spectrometry, which provides information concerning the molecular weight of the analyte. However, the Ti:sapphire laser currently used as the ionization source is costly and involves special skills for operation and maintenance, which prevents its practical use in many applications. In this study, we report on the development of a miniature time-of-flight mass analyzer with a flight tube length of 65 mm for use in combination with a compact highly-repetitive (120–560 kHz) femtosecond Yb laser and a time-correlated single ion counting system. The fundamental beam (1030 nm) was converted into ultraviolet beams emitting at 343, 257, and 206 nm, which was utilized as an efficient two-photon ionization source. A mass resolution of 670 was achieved for the molecular ion of chlorobenzene, the minimum time for measuring a mass spectrum being 0.1 s. This mass spectrometer was used in the on-site real-time monitoring of products appeared by the combustion of plastic, some nerve agent analogs, and an explosive in the air. The interference arising from nitrogen and oxygen in the air was suppressed, since they require nonresonant four- and three-photon ionizations, respectively. The mass spectrometer was combined with a gas chromatograph and used for the comprehensive analysis of polycyclic aromatic hydrocarbons, suggesting its potential advantage for use in the practical trace analysis of organic compounds in the environmental and forensic sciences.

Another Method for Producing Hybrid Plasma: the Hidden Science of the Enclosed Plant Terrarium

Introduction: Enclosed plant terraria have been in use for more than a hundred years but no scientific explanation for their long-term ability to sustain the plants with no water, low light and no air have been proposed. For the present study, we constructed an enclosed and sealed terrarium with a variety of broadleaf plants and measured daily ionization and absolute humidity levels for 1 month compared to a similar container without plants. Methods: Twelve healthy, watered broadleaf plants were placed in a large 19-quart plastic container and sealed with snap closers. A similar but empty container was used as a control. Protocol 1: The time to reach maximum negative ion counts determined by introducing an ion counter into the canister and a hygrometer to measure humidity were monitored daily for 30 days. Protocol 2: After the 30-day study, the plants were removed from the canister. For the next 10 days, the same procedure was followed daily. Results: The time (in seconds) to reach maximum negative ion counts (2999x103 ion counts/sec, for this instrument) and absolute humidity (90+%) in the first 10 days and the last 10 days of the month-long monitoring period were maintained at exceedingly high levels. Even when the plants had been removed from the container. All p values were &gt;0.05. Conclusions: In an enclosed and sealed terrarium with a variety of broadleaf plants, and measured daily ionization and absolute humidity levels for 1 month negative ion counts and humidity were maintained at significantly high levels for another 10 days, even when the plants were removed from the container

Model-based compositional predictions for a differential scanning calorimetry/thermogravimetric analysis-mass spectrometry system used for heat of vaporization measurements

A Differential Scanning Calorimetry/Thermogravimetric Analysis (DSC/TGA) procedure for determination of Heat of Vaporization (HOV) of fuel and surrogate fuel mixtures has been previously utilized for evaluation of oxygenate impacts on spark ignition fuels. This analysis has been further leveraged with mass spectrometry (MS) to elucidate vapor phase compositional changes during evaporation. In this article we focus on a simple system of three compounds (ethanol, n-hexane, and n-octane) to provide a model-based understanding of the evaporation process under these experimental conditions. An Aspen Plus model was set up to provide liquid and vapor phase concentration predictions during mixture evaporation using the initial mixture composition, and measured temperature and mass loss profiles from DSC/TGA experiments. Agreements between the trends of the MS ion count profiles and model composition predictions provide a degree of validation of this modeling approach that can allow the interpretation and extrapolation of DSC/TGA measurements for more complex fuel mixtures.

Optimizing 40Ar/39Ar analyses using an Isotopx NGX-600 mass spectrometer

40Ar/39Ar geochronology relies on magnetic sector mass spectrometers to determine relative isotopic abundances. Ongoing technological developments within noble gas mass spectrometers over the last decade have led to analysis of increasingly smaller samples and higher precision, but also result in more complex data correction and interpretation. We describe a new multi-collector noble gas spectrometer, the Isotopx NGX-600, that is configured to optimize 40Ar/39Ar measurements. The NGX-600 is equipped with 9 Faraday collectors and one ion counting electron multiplier. Each Faraday is equipped with Isotopx ATONA® amplifier technology, enabling measurements spanning a dynamic range of amplified beam current from below 10−16 A to above 10−9 A. The performance of the NGX-600 is evaluated using both a conventional Nier-type ion source, and a next generation low temperature ion source, which allows for trap current variation from 200 μA to 1000 μA. We have performed over 3000 analyses of atmospheric argon to: (1) assess optimal measurement and integration times for blanks, baselines, and air aliquots of various ion intensities, (2) quantify the sensitivity via measurements of first principles 40Ar/39Ar standards, (3) compare the sensitivity between the conventional and new low temperature Nier-type ion sources, and (4) evaluate corrections associated with inter-Faraday biases, instrumental mass bias, and Faraday-multiplier gain. In addition to optimization experiments, we report a comparative analysis of both single crystal fusion and incremental heating data from Quaternary volcanic rocks obtained using both the 5-collector Nu Instruments Noblesse and the NGX-600 spectrometers.