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1.
J Anal At Spectrom ; 37: 898-909, 2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35903413

ABSTRACT

Three 1 2 mass oriented rare earth element (REE) M2+ correction approaches (fixed factor, a dual internal standard, and an in-sample) are evaluated for use in an ICP-MS environmental method update. The multi-variant-based evaluation includes analyzing the same 19 REE-fortified matrices on eight different days over a two-month period using two instrument tunes. These REE-fortified matrices were also analyzed using HR-ICP-MS and ICP-MS/MS to estimate the reference value for use in the principal component analysis (PCA) and hierarchical modeling evaluation. A fixed factor is unable to compensate for matrix and mass dependent drift and because of this it generates the largest across matrix, tune, and day 95th percent confidence bounds for the REE corrections on both As (1.1 ppb) and Se (23 ppb) using samples fortified with 100 ppb Nd, Sm & Gd. The PCA analysis indicated that M2+ ions cluster together across matrix, tune and day better than M1+ and these tighter correlations are reflected in reduced 95th percentile confidence bounds for dual M2+ internal standards (M2+; As = 0.3 ppb; Se = 5.4 ppb; n = 704) relative to M1+ internal standards (M1+; As = 0.6 ppb; Se = 12.0 ppb; n = 1056). The use of an in-sample M2+ correction produced comparable 95th percent confidence bounds (As = 0.2 ppb; Se = 3.4 ppb; n = 352) relative to the M2+ internal standard approaches. Finally, the hierarchical modeling indicated M2+ ions as internal standards tend to minimize the across day variability induced by cone changes and the daily reoccurring matrix shifts in the M2+/M1+ ratio associated with 250 ppm matrices of Na, Ca, and Mg. This internal standard driven reduction in variability can be beneficial in compliance monitoring methods.

3.
Stud Hist Philos Sci ; 91: 77-85, 2022 02.
Article in English | MEDLINE | ID: mdl-34883418

ABSTRACT

Philosophers of biology and biologists themselves for the most part assume that the concept of kin is progenerative: what makes two individuals kin is a direct or indirect function of reproduction. Derivatively, kinship might likewise be presumed to be progenerative in nature. Yet a prominent view of kinship in contemporary cultural anthropology is a kind of constructivism or performativism that rejects such progenerativist views. This paper critically examines an influential line of thinking used to critique progenerativism and support performativism that cites cross-cultural diversity in what I will call kinmaking. I challenge several key assumptions made in moving from this appeal to ethnography to conclusions about kinship and progeneration, arguing that closer scrutiny of both the ethnographic record and inferences that draw on it in fact support progenerative views of kinmaking.


Subject(s)
Anthropology, Cultural , Family , Humans
4.
ACS Omega ; 6(47): 32090-32100, 2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34870030

ABSTRACT

During the e-cigarette, or vaping, product use-associated lung injury (EVALI) investigation, the U.S. FDA's Forensic Chemistry Center (FCC) received numerous sample submissions from various states and other sources. Many of these products were linked directly to patients, while others were not; both categories included used and unused products. Elemental analysis using inductively coupled plasma mass spectrometry (ICP-MS) preceded by microwave-assisted decomposition was carried out on the cartridge contents of 65 of these submitted samples. Challenges encountered included limited sample, high sample viscosity, and adhesion, which necessitated sample preparation techniques not commonly used during routine elemental analysis. The elemental concentrations of contaminants including Pb, As, Cd, Cr, Ni, Cu, and Sn in tetrahydrocannabinol (THC) e-liquids associated with EVALI were determined. Nicotine e-liquid samples collected alongside the THC e-liquid samples were analyzed in tandem during method development. Several THC e-liquid samples contained Pb greater than 0.5 µg/g, while others had part per million levels of Ni, Cu, and/or Cr. This study presents the first detailed report of elemental concentrations in multiple THC e-liquid samples including those from informal/illicit sources and also delves into the method considerations needed for testing a viscous, hydrophobic sample matrix in limited quantity.

5.
Monash Bioeth Rev ; 39(2): 169-176, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34913155

ABSTRACT

This commentary continues an exchange on eugenics in Monash Bioethics Review between (Anomaly in Defending Eugenics: From Cryptic Choice to Conscious Selection 35:24-35, 2018), (Wilson in Eugenics Undefended 37:68-75, 2019), and (Veit in Can 'Eugenics' be Defended? 39:60-67, 2021). The eponymous question, "Can 'Eugenics' be Defended?", is multiply ambiguous and does not receive a clear answer from Veit et al.. Despite their stated desire to move beyond mere semantics to matters of substance, Veit et al. concentrate on several uses of the term "eugenics" that pull in opposite directions. I argue, first, that (Veit in Can 'Eugenics' be Defended? 39:60-67, 2021) makes much the same error as does (Anomaly in Defending Eugenics: From Cryptic Choice to Conscious Selection 35:24-35, 2018) in characterizing eugenics; second, that the paper misunderstands the relationship between eugenics and enhancement; and third, that it distorts the views expressed in my "Eugenics Undefended".


Subject(s)
Bioethics , Eugenics , Humans
6.
Front Chem ; 9: 734793, 2021.
Article in English | MEDLINE | ID: mdl-34434923

ABSTRACT

Incidence of e-cigarette, or vaping, product use-associated lung injury (EVALI) has been linked to the vaping of tetrahydrocannabinol (THC) products to which vitamin E acetate (VEA) has been added. In this work we vaped THC/VEA mixtures at elevated power levels using a variety of ceramic coil vaping cartridges and a commercially available vaping device, while simultaneously measuring temperature and collecting the vaporized condensate. The collected vapor condensate was analyzed for evidence of VEA decomposition by GC/MS, GC/FT-IR/MS, and LC-APCI-HRMS/MS. Mean temperature maxima for all examined cartridges at the selected power exceeded 430°C, with a range of 375-569°C, well beyond that required for thermal decomposition of VEA. The percent recovery of VEA and Δ9-THC from the vaporized mixture in six cartridges ranged from 71.5 to 101% and from 56.4 to 88.0%, respectively. Analysis of the condensed vaporized material identified VEA decomposition products duroquinone (DQ), 1-pristene, and durohydroquinone monoacetate (DHQMA); a compound consistent with 4-acetoxy-2,3,5-trimethyl-6-methylene-2,4-cyclohexadienone (ATMMC) was also detected. The concentration of DQ produced from vaporization of the THC/VEA mixture in one cartridge was found to be 4.16 ± 0.07 µg per mg of vapor condensate.

7.
Anal Chem ; 92(3): 2374-2378, 2020 02 04.
Article in English | MEDLINE | ID: mdl-31951379

ABSTRACT

Vitamin E acetate (VEA) has recently been identified as a potential chemical of concern in the investigation of e-cigarette, or vaping, product use associated lung injury (EVALI). According to the Centers for Disease Control and Prevention (CDC), most patients report a history of using tetrahydrocannabinol (THC)-containing e-cigarette or vaping products; approximately 50% of the THC-containing vaping products examined by the Food and Drug Administration (FDA) in this investigation have been found to contain VEA. This letter demonstrates that THC and VEA exist in the unvaped e-liquids, vaped e-liquids, and the aerosol produced from vaporizing the mixture, as a hydrogen bonded THC/VEA complex linked by the THC hydroxyl and VEA carbonyl groups. Additional work should therefore be considered to investigate what happens to this complex in the lungs.


Subject(s)
Acetates/chemistry , Dronabinol/chemistry , Vitamin E/chemistry , Aerosols/chemistry , Hydrogen Bonding
8.
Monash Bioeth Rev ; 37(1-2): 68-75, 2019 10.
Article in English | MEDLINE | ID: mdl-31325149
9.
J Anal At Spectrom ; 34(10): 2094-2104, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-32280153

ABSTRACT

Rare earth elements (REE) can produce M2+ ions in ICP-MS and 150Nd2+, 150Sm2+, and 156Gd2+ can produce false positives on 75As and 78Se. Alternative instrumental tuning conditions, that utilize lower He flows within the collision cell, reduce these false positives by a factor of 2 (to 0.8 ppb As and 19 ppb Se in solutions containing 50 ppb Nd and Gd) with comparable 16O35Cl+ reduction (<100 ppt false 51V in 0.4% HCl) and Se sensitivity (DL < 1 ppb). Further reduction of these false positives is achieved by estimating the M2+ correction factors and utilizing them in the interference-correction software. Approaches to estimating the M2+ correction factor were evaluated with an emphasis on techniques that tolerate daily variability in end-user backgrounds and their ability to reduce the initial and ongoing purity requirements associated with the rare earth standards used to estimate the M2+ correction factor. The direct elemental and polyatomic overlaps associated with unit-mass approaches tend to overcorrect as non-rare-earth signals as small as 30 cps at the unit mass can induce bias relative to the <300 cps signals associated with the M2+ from a 50 ppb REE standard solution. Alternatively, shifting the M2+ estimate to a half mass (i.e., m/z 71.5: 143Nd2+) eliminates the direct overlap source of bias and allows the unit mass signal to approach 150000 cps before it bleeds over on the 1/2 mass because of abundance sensitivity limitations. The performance of the half-mass approach was evaluated in reagent water and regional tap waters fortified with Nd, Sm, and Gd at 2 ppb and 50 ppb. In addition, a half-mass in-sample approach was also evaluated. This approach was found to be beneficial relative to the external or fixed-factor half-mass approach as it could compensate for instrument drift and matrix-induced shifts in the M2+ factors. Finally, all results were evaluated relative to the As and Se concentrations determined using an ICP-QQQ in mass shift mode and a high-resolution ICP-MS.

10.
J Agric Food Chem ; 65(20): 4193-4199, 2017 May 24.
Article in English | MEDLINE | ID: mdl-28457128

ABSTRACT

A multilaboratory validation (MLV) was performed to extend the U.S. Food and Drug Administration's (FDA) analytical method Elemental Analysis Manual (EAM) §4.10, High Performance Liquid Chromatography-Inductively Coupled Plasma-Mass Spectrometric Determination of Four Arsenic Species in Fruit Juice, to include wine. Several method modifications were examined to optimize the method for the analysis of dimethylarsinic acid, monomethylarsonic acid, arsenate (AsV), and arsenite (AsIII) in various wine matrices with a range of ethanol concentrations by liquid chromatography-inductively coupled plasma-mass spectrometry. The optimized method was used for the analysis of five wines of different classifications (red, white, sparkling, rosé, and fortified) by three laboratories. Additionally, the samples were fortified in duplicate at levels of approximately 5, 10, and 30 µg kg-1 and analyzed by each participating laboratory. The combined average fortification recoveries of dimethylarsinic acid, monomethylarsonic acid, and inorganic arsenic (iAs the sum of AsV and AsIII) in these samples were 101, 100, and 100%, respectively. To further demonstrate the method, 46 additional wine samples were analyzed. The total As levels of all the wines analyzed in this study were between 1.0 and 38.2 µg kg-1. The overall average mass balance based on the sum of the species recovered from the chromatographic separation compared to the total As measured was 89% with a range of 51-135%. In the 51 analyzed samples, iAs accounted for an average of 91% of the sum of the species with a range of 37-100%.


Subject(s)
Arsenic/analysis , Chromatography, High Pressure Liquid/methods , Food Contamination/analysis , Mass Spectrometry/methods , Wine/analysis , Laboratories/standards
11.
Food Chem ; 218: 313-320, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-27719915

ABSTRACT

Selenium-enriched dietary supplements containing various selenium compounds are readily available to consumers. To ensure proper selenium intake and consumer confidence, these dietary supplements must be safe and have accurate label claims. Varying properties among selenium species requires information beyond total selenium concentration to fully evaluate health risk/benefits A LC-ICP-MS method was developed and multiple extraction methods were implemented for targeted analysis of common "seleno-amino acids" and related oxidation products, selenate, selenite, and other species relatable to the quality and/or accuracy of the labeled selenium ingredients. Ultimately, a heated water extraction was applied to recover selenium species from non-selenized yeast supplements in capsule, tablet, and liquid forms. For selenized yeast supplements, inorganic selenium was monitored as a means of assessing selenium yeast quality. A variety of commercially available selenium supplements were evaluated and discrepancies between labeled ingredients and detected species were noted.


Subject(s)
Dietary Supplements/analysis , Selenium/analysis , Dietary Supplements/standards , Dose-Response Relationship, Drug , Selenic Acid/analysis , Selenium Compounds/analysis , Selenocysteine/analogs & derivatives , Selenocysteine/analysis , Selenomethionine/analysis
12.
Article in English | MEDLINE | ID: mdl-27107244

ABSTRACT

An analytical method for determination of the iodine species 3-monoiodotyrosine (MIT), iodide, 3,5-diiodotyrosine (DIT), 3,5-diiodothyronine (3, 5-T2), 3,5,3'-triiodothyronine (T3), and thyroxine (T4) in dog foods and treats is reported. Iodine speciation was carried out using a HPLC method capable of both anion-exchange and reversed-phase retention coupled with inductively coupled plasma mass spectrometry detection (LC-ICP-MS). The method was evaluated by the analysis of the iodine species concentrations in twelve dog foods and treats following enzymatic digestion. The concentrations of MIT, iodide, DIT, T3, and T4 in the samples ranged from 0.64-59.5µg/g, 0.86-4.05µg/g,

Subject(s)
Animal Feed/analysis , Chromatography, High Pressure Liquid/methods , Iodine Compounds/analysis , Iodine Compounds/chemistry , Iodine/chemistry , Mass Spectrometry/methods , Animals , Dogs , Limit of Detection , Linear Models , Reproducibility of Results
13.
J AOAC Int ; 97(3): 956-62, 2014.
Article in English | MEDLINE | ID: mdl-25051650

ABSTRACT

The polyatomic background at the major isotope of Cr was evaluated as a function of collision cell gas flow rate using three different mobile phases. The stability of Cr VIwas evaluated as a function of solution pH by fortifying samples with enriched 53Cr VI. The 53Cr VI recovery was > or =95% at pH 7.8, but by pH 6.2 a significant amount of the enriched spike was recovered as 53Cr III-EDTA. The instability of Cr III at pHs above 7.8 required that Cr III be chelated prior to speciation. The concentration of EDTA was optimized by evaluating Cr III recoveries in six finished drinking waters, a U.S. Geological Survey reference water, and a challenge water fortified with competing matrix cations. If the Cr III was allowed to precipitate (characteristic of shipping a sample without field preservation), acceptable recoveries of Cr III required the sample to be heated to 70 degrees C in 10 mM EDTA to quantitatively produce the Cr III-EDTA complex. The overall preservation/speciation approach was evaluated using an enriched 53Cr VI and natural Cr III in seven drinking water matrixes over a 46 day period. A linear least squares analysis was performed on each water, and the corresponding P-values were estimated. The method detection limits for Cr III-EDTA and Cr VI were 0.06 and 0.1 pglL, respectively.


Subject(s)
Chromatography, Liquid/methods , Chromium/analysis , Drinking Water/analysis , Mass Spectrometry/methods , Edetic Acid/chemistry , Hydrogen-Ion Concentration , Limit of Detection , Spectrophotometry, Atomic
14.
Electroanalysis ; 25(2)2013 Feb.
Article in English | MEDLINE | ID: mdl-24235807

ABSTRACT

Zinc (Zn) homeostasis is required for a functional immune system. Critically ill patients often exhibit decreased Zn serum concentrations and could potentially benefit from Zn supplementation as a therapeutic strategy. However, the conventional approaches to monitoring Zn are time consuming and costly. This work reports on detection of Zn by anodic stripping voltammetry (ASV) on bismuth electrodes in a microfabricated electrochemical cell. The working potential window of the electrodeposited bismuth film electrode was investigated by cyclic voltammetry, while square wave ASV was used for measuring Zn in acetate buffer and blood serum. Conditions critical to sensing, such as preconcentration potential, preconcentration time, and buffer pH, were optimized for Zn detection. The sensor was successfully calibrated with pH 6 acetate buffer in the physiologically-relevant range of 5 µM to 50µM Zn and exhibited well-defined and highly repeatable peaks. The sensor was used to demonstrate measurement of Zn in blood serum digested in HCl. The results of this work show that Zn detection in serum is possible with smaller sample volumes (µL vs. µL) and faster turnaround time (hours vs. days) as compared with the conventional spectroscopic methods.

15.
Behav Brain Sci ; 36(2): 162-3, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23507118

ABSTRACT

I propose that in at least some cases, objects of artistic appreciation are best thought of not simply as causes of artistic appreciation, but as parts of the cognitive machinery that drives aesthetic appreciation. In effect, this is to say that aesthetic appreciation operates via extended cognitive systems.


Subject(s)
Art/history , Cognition , Esthetics/history , Esthetics/psychology , Psychological Theory , Psychology/methods , Humans
16.
Wiley Interdiscip Rev Cogn Sci ; 4(3): 319-325, 2013 May.
Article in English | MEDLINE | ID: mdl-26304209

ABSTRACT

Traditional views in philosophy of mind and cognitive science depict the mind as an information processor, one whose connections with the body and the world are of little theoretical importance. On the contrary, mounting empirical evidence shows that bodily states and modality-specific systems for perception and action underlie information processing, and that embodiment contributes to various aspects and effects of mental phenomena. This article will briefly review and discuss some of this evidence and what it implies. By challenging mainstream accounts of mind and cognition, embodiment views offer new ways of conceptualizing knowledge and suggest novel perspectives on cognitive variation and mind-body reductionism. WIREs Cogn Sci 2013, 4:319-325. doi: 10.1002/wcs.1226 For further resources related to this article, please visit the WIREs website.

17.
Biomed Microdevices ; 13(4): 695-703, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21479538

ABSTRACT

This work describes development of a lab-on-a-chip sensor for electrochemical detection of highly electronegative heavy metals such as manganese and zinc by anodic stripping voltammetry. The sensor consists of a three-electrode system, with a bismuth working electrode, a Ag/AgCl reference electrode, and a Au auxiliary electrode. Hydrolysis at the auxiliary electrode is a critical challenge in such electrochemical sensors as its onset severely limits the ability to detect electronegative metals. The bismuth working electrode is used due to its comparable negative detection window and reduced toxicity with respect to a conventional mercury electrode. Through optimization of the sensor layout and the working electrode surface, effects of hydrolysis were substantially reduced and the potential window was extended to the -0.3 to -1.9 V range (vs. Ag/AgCl reference electrode), which is far more negative than what is possible with conventional Au, Pt, or carbon electrodes. The described lab-on-a-chip sensor for the first time permits reliable and sensitive detection of the highly electronegative manganese. The favorable performance of the bismuth electrode coupled with its environmentally-friendly nature make the described sensor attractive for applications where disposable chips are desirable. With further development and integrated sample preparation, the lab-on-a-chip may be converted into a point-of-care platform for monitoring heavy metals in blood (e.g., assessment of manganese exposure).


Subject(s)
Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Electrochemical Techniques/instrumentation , Lab-On-A-Chip Devices , Metals, Heavy/blood , Potentiometry/instrumentation , Bismuth/chemistry , Cadmium/blood , Carbon/chemistry , Electrochemical Techniques/methods , Electrodes , Equipment Design , Humans , Lead/blood , Male , Manganese/blood , Mercury/chemistry , Surface Properties , Zinc/blood
18.
Anal Chem ; 83(10): 3725-9, 2011 May 15.
Article in English | MEDLINE | ID: mdl-21504209

ABSTRACT

Spectroelectrochemical sensing in an optically transparent thin layer electrode (OTTLE) cell was used for detecting the polycyclic aromatic hydrocarbon (PAH) biomarkers 1-hydroxypyrene (1-pyOH) and 1-hydroxypyrene-glucuronide (1-pyOglu) in phosphate buffer and artificial urine. This approach uses selective electrochemical modulation of a fluorescence signal by sequentially oxidizing the analytes in an OTTLE cell to distinguish between their overlapping fluorescence spectra. This technique allows for complete oxidation and signal modulation in approximately 15 min for each analyte; a mixture of 1-pyOH and its glucuronic acid conjugate can be analyzed in 30 min. Calibration curves consisting of the fluorescence change vs analyte concentration for 1-pyOH and 1-pyOglu yielded linear ranges from 10 nM to 1 µM and from 1 nM to 1 µM, respectively. With the use of these results, the calculated limits of detection were determined to be 1 × 10(-8) M for 1-pyOH and 9 × 10(-11) M for 1-pyOglu.


Subject(s)
Air Pollutants, Occupational/analysis , Electrochemical Techniques/methods , Glucuronates/analysis , Pyrenes/analysis , Pyrenes/metabolism , Air Pollutants, Occupational/metabolism , Biomarkers/analysis , Electrodes , Glucuronates/urine , Humans , Oxidation-Reduction , Polycyclic Aromatic Hydrocarbons/metabolism , Spectrometry, Fluorescence/methods
20.
J Stud Alcohol ; 67(4): 591-9, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16736079

ABSTRACT

OBJECTIVE: This study develops a mathematical model of alcohol abuse in structured populations, such as communities and college campuses. The study employs a network model that has the capacity to incorporate a variety of forms of connectivity membership besides personal acquaintance, such as geographic proximity and common organizations. The model also incorporates a resilience dimension that indicates the susceptibility of each individual in a network to alcohol abuse. The model has the capacity to simulate the effect of moving alcohol abusers into networks of nonabusers, either as the result of treatment or membership in self-help organizations. METHOD: The study employs a small-world model. A cubic equation for each person (vertex on a graph) governs the evolution of an individual's state between 0 and 1 with regard to alcohol dependence, with 1 indicating absolute certainty of alcohol dependence. The simulations are dependent on initial conditions, the structure of the network, and the resilience distribution of the network. The simulations incorporate multiple realizations of social networks, showing the effect of different network structures. RESULTS: The model suggests that the prevalence of alcohol abuse can be minimized by treating a relatively small percentage of the study population. In the small populations that we studied, the critical point was 10% or less of the study population, but we emphasize that this is within the limitations and assumptions of this model. CONCLUSIONS: The use of a simple model that incorporates the influence of the social network neighbors in structured populations shows promise for helping to inform treatment and prevention policy.


Subject(s)
Alcoholism/epidemiology , Models, Theoretical , Social Support , Alcoholics Anonymous , Alcoholism/psychology , Alcoholism/therapy , Humans , Interpersonal Relations , Models, Psychological , Prevalence
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