bluuebunny/crossref_metadata_2025 huggingface dataset:
Thin Layer Chromatographic Determination of Aflatoxin B1 in Eggs
Authors: Trucksess Mary W , Stoloff Leonard , Pons Walter A , Cucullu Alva F , Lee Louise S , Franz Anthony O
Published: February 2020

A method for determining aflatoxin in dairy products was modified for eggs, initially by additional cleanup steps. The modified method proved practical for use in survey analyses and was sufficiently sensitive to detect aflatoxin B1 at levels less than 1 ng/g in eggs from hens on experimentally contaminated feed and in spiked eggs; interfering compounds in eggs received from many different producing areas were eliminated. Although recovery was greater than 75% when the aflatoxin was extracted immediately after spiking, recovery was usually less than 30% when the aflatoxin was extracted after more than 24 hr. Adding sodium chloride, sodium sulfate, or urea to the extracting solvent remedied this defect, which is thought to be related to the binding of aflatoxin to egg protein.
Analysis of Foods for Arsenic and Selenium by Acid Digestion, Hydride Evolution Atomic Absorption Spectrophotometry
Authors: Ihnat Milan , Miller Hanford J
Published: February 2020

A method based on acid digestion, hydride evolution atomic absorption spectrophotometry for estimating microgram and submicrogram quantities of As and Se in foods was developed and evaluated. Samples up to 3 g dry weight were digested with HNO3-HClO4-H2SO4. As and Se in aliquots of the digests were reduced with NaBH4 to volatile hydrides, using laboratory-constructed and commercially available generators. As and Se were estimated by transient signal atomic absorbance measurements as the hydrides were decomposed in an Ar-H2-entrained air flame. Recoveries of inorganic As and Se added at levels of 0.1—1.0 μg/g to a variety of foods ranged from 70 to 125%. Analyses of several standard reference samples indicated the method is capable of recovering native analytes. Detection limits for the determinative step and the method as a whole were as low as 5 and 25 ng, respectively, for both elements.
Gas-Liquid Chromatographic Determination of α-Cyano-3-phenoxybenzyl α-Isopropyl-4-chlorophenylacetate Residues in Cabbage
Authors: Talekar Narayan S
Published: February 2020

A gas-liquid chromatographic method is described for residues of a synthetic pyrethroid, Sumicidin (α-cyano-3-phenoxybenzyl α-isopropyl-4-chlorophenylacetate), on cabbage. The plant material is Soxhlet-extracted with hexaneacetone (1+l) and subsequently cleaned up on Florisil with benzene-ethyl acetate (9+1) eluting solvent. Gas-liquid chromatographic analysis was performed on a 0.5 m × 2 mm stainless steel column containing 3% OV-101 + 3% Apiezon L on 80–100 mesh Gas-Chrom Q, with tritium electron capture detection. Sumicidin recovery was 97% when added at the 0.5 ppm level. Routine Sumicidin residue monitoring data presented.
Liquid Chromatographic Determination of Azinphos Methyl Oxon in Foliar Dislodgeable Residues and in Soil Surface Dusts from an Azinphos Methyl-Treated Orange Grove
Authors: Kvalvåg John , Ott Daniel E , Gunther Francis A
Published: February 2020

Specific parts of the worker environment in an orange grove that had been sprayed with azinphos methyl formulation were tested for azinphos methyl oxon. Extracts of soil surface dusts and dislodgeable residues from orange leaf surfaces were prepared and analyzed by liquid chromatographic procedures incorporating an ultraviolet absorption detector primarily for quantitation and an on-stream chemical reaction detector primarily for confirmation. Azinphos methyl oxon residues were found in both types of samples collected 3–59 days after spraying. Foliar dislodgeable residues of the oxon ranged from a high of 0.057 μg/sq cm of leaf surface on the 17th day to a low of 0.014 μg/sq cm on the 59th day for trees treated with a low-volume spray. The corresponding range in soil dust samples was 5.2 μg/g (ppm) of dust on the 10th day to 1.4 μg/g on the 59th day. Values were 9.7 and 2.7 μg/g, respectively, for samples from under trees similarly treated with a high-volume spray.
Microbiological Assay for Saponin in Alfalfa Products
Authors: Livingston A Lyle , Whitehand Linda C , Kohler George O
Published: February 2020

A bioassay is described for determining medicagenin-type saponin in dried alfalfa, leaf protein concentrates, and alfalfa sprouts. Samples are extracted by refluxing 2½ hr with 50% ethanol, ethanol is evaporated, and aliquots of an aqueous solution are added to potato dextrose agar (PDA) and assayed for saponin by using the fungus Trichoderma viride. The growth of the fungus on PDA is compared with a standard saponin, and saponin levels are calculated by means of a slope ratio analysis.
Collaborative Study of Determination of Amount of Seafood in Seafood Cocktails
Authors: King Frederick J , Regan Paul J
Published: February 2020

Method 18.B02–18.B03 for shrimp in shrimp cocktail was used to determine the amount of seafood ingredient in 6 seafood cocktails: clam, crab body meat, crab leg meat, fish, oyster, and shrimp. Duplicate samples of each kind of seafood cocktail were studied by 10 collaborators. Their results indicate that the method is suitable for a variety of seafood cocktails if 2 revisions are made. A revised version of 18.B02— 18.B03 was adopted as a procedure for seafood in seafood cocktails other than shrimp.
Collaborative Study of the Differential Pulse Polarographic Analysis of Cacodylate Injections
Authors: Holak Walter
Published: February 2020

Samples containing cacodylate are heated with magnesium nitrate to decompose the cacodylate moiety, releasing pentavalent arsenic. The arsenic is reduced to the polarographically active trivalent state by heating with hydrobromic acid and hydrazine sulfate. Differential pulse polarography is performed in a 1M HQ supporting electrolyte, using a standard addition method for quantitation. The results from 6 collaborators showed an average of 97.00% of declared potency for commercial ampoules, with a relative standard deviation of 2.99%. Two synthetic cacodylic acid solutions prepared to contain 9.01 and 30.02 mg/ml gave averages of 100.03 and 99.38% of amount added, with relative standard deviations of 1.56 and 1.42%, respectively. The method has been adopted as official first action.
Interference by Acetylated Aminoacetic Acid in Nonaqueous Titration of Nicotinic Acid
Authors: Soliman Sobhi A , Abdine Hassan , Morcos Magdi G
Published: February 2020

A nonaqueous titration procedure is described for determining aminoacetic acid and nicotinic acid in mixtures and elixirs. The effect of acetylated aminoacetic acid on the potentiometric titration of nicotinic acid is discussed. Above a 2:1 ratio of aminoacetic acid to nicotinic acid, the former interferes with titration. The titration curve of nicotinic acid becomes progressively flatter with increasing amounts of the acetylated compound. Above this ratio, nicotinic acid had to be separated from the mixture by dissolving in ethanol for a successful titration.
Gas-Liquid Chromatographic Determination of β-Asarone in Wine: Collaborative Study
Authors: Dyer Randolph H
Published: February 2020

The gas-liquid chromatographic determination of β-asarone (cis-2,4,5-trimethoxy-l-propenylbenzene) in wine was collaboratively studied by 9 analysts. The samples were first distilled and then extracted into hexane prior to chromatography. The mean recovery for 8 spiked samples, analyzed as blind duplicates, was 89.27%. The reproducibility coefficient of variation was 17.9%, and the repeatability coefficient of variation was 8.3%. No unfavorable remarks were noted. The method has been adopted as official first action.
Preliminary Collaborative Study of Modified Spectrophotometric Determination of Pyrantel Tartrate in Swine Feeds by the Method of Standard Additions
Authors: Litchman Mark A
Published: February 2020

A modified spectrophotometric method for determining pyrantel tartrate in swine feeds was subjected to a preliminary collaborative study. Two small-scale commercial pyrantel-medicated feed samples (0.0881 and 0.0106%) were assayed in replicate by 4 collaborators. The mean results of all laboratories were 0.0862 and 0.0112%. The mean coefficients of variation were 10.57 and 6.48%, respectively. Suggestions for improving recovery include the following: complete dissolution of standard, use of analytical grade KI, careful phase separation, thorough mixing, and minimum exposure of compound to light.
Extraction, Gas-Liquid Chromatographic Detection, and Quantitation of Hexachlorophene Residues from Plant Tissues High in Lipid Content
Authors: Van Auken Oscar W , Hulse Michael , Durocher Constance L
Published: February 2020

A method has been developed for the extraction, cleanup, derivatization, detection, and quantitation of hexachlorophene (HCP) residues from 2 types of plant storage tissue high in lipid content. Wet soybean or peanut tissue was homogenized and extracted with ethyl ether and chromatographed on silica gel to remove the neutral lipids. The cleaned up sample was methylated with diazomethane and the dimethoxyhexachlorophene was eluted from a second silica gel column and chromatographed on a 6′ glass column packed with 3% OV-1 or 3% SE-30 on Gas-Chrom Q. The instrument detection limit for the 63Ni electron capture detector was <0.1 ng for dimethoxyhexachlorophene and about 1 ppb for HCP residue in plant issue. Recovery of 10–420 ppb HCP added to tissue averaged 90.9±5.7%. Interfering substances were removed, column life was increased, peak sharpness was increased, and tailing of the parent compound was decreased by using appropriate column chromatography.
Microbiological Plate and Turbidimetric Assays of Chlortetracycline in Feeds: Collaborative Study
Authors: Ragheb Hussein S
Published: February 2020

The manual and automated turbidimetric assays and a modified official plate assay for Chlortetracycline (CTC-HCl) in feed were collaboratively studied. Three feed samples (swine feed, 100 g CTC-HCl/ton; premix I, 20 g each of CTC-HCl and sulfamethazine/lb, and 10 g penicillin/lb; and premix II, 50 g CTC-HCl/lb) were analyzed at 2 dilutions. Twelve laboratories conducted the plate assay; 8 laboratories, the manual turbidimetric method ; and 7 laboratories, the Autoturb analysis. Within a method, there was no significant difference between dilutions. Between methods, there was a significant difference between the manual turbidimetric plate assays only for swine feed. However, the same sample dilutions or the average values of the 2 dilutions for both methods showed no statistical difference. Among the collaborators, the slope of CTC-HCl standard curve varied between about 2.0 and 3.0 for the plate method. The turbidimetric assay has been adopted as official first action for feeds containing >20 g CTC-HCl/lb.
Atomic Absorption Spectroscopy of Copper and Iron in Plant Material
Authors: Boline Duane R , Schrenk W G
Published: February 2020

An atomic absorption spectroscopic (AAS) method is described for the determination of copper and iron by direct aspiration of a solution of an ashed sample in an alcohol-water mixture. The method has been applied to samples containing 2.0–31.9 μg Cu/g and 15.5–196 Fe/g. Operating conditions for using an acetylene-air flame have been established. The hollow cathode current needed to be carefully controlled for the copper analysis. No significant interference was noted from other elements commonly present in plants. Wet and dry ashing procedures provided comparable results. Recovery of added amounts of copper and iron ranged from 92 to 101% and 94 to 104%, respectively; most results were near 100%. The official AOAC colorimetric methods and the AAS method were compared and were comparable in reliability and accuracy. The AAS method is simpler and faster.
Analysis of Fat-Soluble Vitamins. XV. Confirmation of Isotachysterol in Vitamin D Concentrates
Authors: De Vries Ellen J , Mulder Frits J , Borsje Ben
Published: February 2020

The reaction with maleic anhydride yielding Diels-Alder adducts is used to distinguish vitamin D isomers. Treatment at 100°C for 3 hr eliminates the fast-reacting (tachysterol and trans-vitamin D) and slow-reacting (cis-vitamin D and previtamin D) isomers. However, isotachysterol is not eliminated. The procedure has been incorporated as a confirmation test for isotachy sterol in the official final action method for the determination of vitamin D in concentrates, 43.B14–43.B24.
High Pressure Liquid Chromatographic Determination of Vitamin D in Fortified Milk
Authors: Thompson James N , Maxwell William B , L’Abbé Mary
Published: February 2020

Vitamin D was determined in fortified milk by high pressure liquid chromatography (HPLC) after preliminary purification involving saponification at room temperature and low pressure chromatography on hydroxyalkoxypropyl Sephadex (HAPS). The saponified milk (50 ml) was extracted with ether, the extract was chromatographed in hexane on a 60 × 1 cm column of HAPS, and the absorption of the eluate at 254 nm was recorded. The fraction containing vitamin D was collected by using the position of characteristic peaks in the chromatogram as a guide. An aliquot of this fraction was chromatographed in an HPLC system on a 25 cm × 3.2 mm column of LiChrosorb Si 60 5 μm silicic acid, using 0.6% isopropanol in hexane (50% water-saturated) as the mobile phase. The absorption was set at 265 nm. Vitamin D was cleanly separated from other absorbing materials, and the amount could be calculated from the peak area. Recovery of added vitamin D was greater than 97 %.
Simplified Micro Perchlorination Method for Polychlorinated Biphenyls in Biological Samples
Authors: Crist Howard L , Moseman Robert F
Published: February 2020

Simplified methodology is presented for the micro determination of polychlorinated biphenyls (PCBs) in biological samples, by conversion to the decachlorobiphenyl (DCB) derivative. Beef adipose tissue and human milk extracts were fortified with PCB standards at 0.1–5.0 ppm, and perchlorinated with antimony pentachloride (SbCl5). Several Aroclors representing various degrees of chlorine content were investigated to assess the efficiency of conversion to DCB. Samples were cleaned up on a Florisil mini column and the PCBs were quantitated by electron capture GLC. Several chlorinated pesticides which were subjected to the perchlorination procedure did not interfere. As little as 0.1 ppm PCBs in 500 mg tissue extract can be recovered at 79–99%. The background DCB content of several brands of SbCl5 was determined. The levels of PCBs in human milk obtained by the perchlorination technique are compared with data acquired by electron capture gas-liquid chromatography in which the individual chlorobiphenyls in the sample are measured.
High Pressure Liquid Chromatographic Determination of Vitamin D3 in Livestock Feed Supplements
Authors: Ray Allen C , Dwyer J Nelson , Reagor John C
Published: February 2020

Vitamin D3 is determined in livestock feed supplements by high pressure liquid chromatography (HPLC). Extracts of the samples are quantitated using normal phase chromatography. If interfering co-extractives are present, an aliquot of the extract is injected on the normal phase column, and the fraction corresponding to vitamin D3 is collected. The vitamin fraction is then further cleaned up and separated from interferences by reverse phase chromatography, and quantitated by measuring the ultraviolet absorption at 254 and 280 nm. The method measures actual vitamin D3 content in the presence of pre-vitamin D, tachysterol, isotachysterol, and vitamin A.
Gas-Liquid Chromatographic Determination of Total Inorganic Iodine in Milk
Authors: Bakker Hendrik J
Published: February 2020

Total inorganic iodine in milk is determined by conversion to iodobutanone, which is quantitated by gas-liquid chromatography and electron capture detection. As little as 10 μg/L can be determined. The thyroid-active iodine content of milk can be determined rapidly with a relative standard deviation of 1.9%. Average recoveries for added iodide and iodine were 95.5 and 94.6%, respectively.
Gas-Liquid Chromatographic Determination of Isosorbide Dinitrate in Tablets
Authors: Prue David G , Johnson Raymond N , Kho Boen T
Published: February 2020

A gas-liquid chromatographic (GLC) method is described for determining isosorbide dinitrate (ISDN) in tablets. ISDN is extracted from tablet excipients by a 2-phase system composed of water-ethyl ether, and detected and quantitated with a flame ionization detector after separation from the internal standard (glyceryl tributyrate) on a 3% OV-210 column. Ten replicate assays on 2 different batches of tablets, each containing 5 mg ISDN, gave coefficients of variation of 1.16 and 1.48%, respectively. Comparison of results obtained for tablets containing 5, 10, and 40 mg ISDN, and for diluted isosorbide dinitrate raw material containing 25% ISDN, showed good correlation among the GLC, USP colorimetric, and USP polarographic procedures. Assay of synthetic mixtures containing ISDN, isosorbide-2-mononitrate, and isosorbide-5-mononitrate demonstrated that the GLC procedure is specific for ISDN, whereas the USP polarographic procedure is subject to interference from the mononitrates.
Atomic Absorption Spectrophotometric Determination of Lead, Cadmium, Zinc, and Copper in Clams and Oysters: Collaborative Study
Authors: Capar Stephen G
Published: February 2020

In the method studied, clams and oysters are dry ashed at 475°C, the ash is dissolved in dilute HNO3, and Pb, Cd, Zn, and Cu are determined by flame atomic absorption spectrophotometry (AAS). Sample solutions containing levels of Pb and Cd too low for direct AAS are extracted as the 1-pyrrolidinecarbodithioate complex into n-butyl acetate before AAS. The method was subjected to a collaborative study to determine the precision and accuracy of the analysis. Concentration ranges in the samples studied were approximately 0.06–2 ppm Pb, 0.03–2 ppm Cd, 40–600 ppm Zn, and 5–50 ppm Cu. Within these ranges, Cd levels <0.5 ppm and Pb at all levels required extraction prior to AAS. The average coefficients of variation for Pb, Cd, Zn, and Cu were, respectively, 66.0, 93.2, 8.5, and 20.5% for the lowest levels and 13.5, 3.8, 6.7, and 6.8% for the highest levels. Recoveries were computed by using the sum of the average collaborative results for the totally unfortified samples plus the fortification levels as the expected concentration. The average recoveries of Pb, Cd, Zn, and Cu were, respectively, 94.0, 99.7, 99.3, and 100.2 % for the lowest fortification level and 94.8, 95.6, 96.5, and 97.5% for the highest level. High levels of Cu and/or Zn caused incomplete extraction of Pb and Cd, with Cd being affected more severely than Pb. Data obtained also suggest that background corrections may be needed for determining Zn and Cd with the direct aspiration technique. No recommendation is made for official action.
Internal Carotid Artery Dissection Presenting as Partial Horner’s Syndrome and Vertigo
Authors: Teixeira Jeffrey C , Jackson Paula J
Published: February 2020

Distinguishing between central and peripheral causes of vertigo can be challenging not only in an acute setting but also in chronic settings. A thorough review of systems and physical exam can assist providers in differentiating central versus peripheral etiologies and the need for urgent imaging. In this case, a 47-year-old man presented with vertigo, right-sided hearing loss, right-sided headache, and right-sided facial pain that began 4 weeks before while the patient was on a cruise ship. His physical exam findings were notable for anisocoria with right pupil 3.5 and left pupil 4.5, mild ptosis on the right side, positive Romberg test to the right, and Fakuda test with deviation to the right. Urgent magnetic resonance imaging revealed dissection of the right cervical internal carotid artery with a nonocclusive intramural hematoma. This case illustrates the importance of imaging in vertigo patients in which a central etiology is suspected. It further demonstrates that isolated partial Horner’s or unilateral headache may indeed be the only presenting sign in a carotid dissection.
Tiers for Education and Training in Global Health for Military Engagement
Authors: Burkett Edwin K , Aguirre Diana L
Published: February 2020

This article describes four tiers for knowledge required by U.S. military personnel to effectively execute global health activities. Department of Defense policy does not identify a formal global health education path for personnel responsible for global health activities. Department of Defense must implement formal education programs to improve mission success and favorable health outcomes.
The screening of blood by Aspergillus PCR and galactomannan ELISA precedes BAL detection in patients with proven and probable IA
Authors: Springer Jan , Löffler Jürgen , Einsele Hermann , White P Lewis
Published: February 2020

Early detection of Aspergillus infection has the potential to facilitate a more effective management of invasive disease. Data from probable/proven cases of invasive aspergillosis (IA) with a positive galactomannan enzyme-linked immunosorbent assay (GM) bronchoalveolar lavage fluid (BALF) was analyzed in respect to serum GM and/or polymerase chain reaction (PCR) screening of blood samples prior to, or concurrent with bronchoscopy. Concurrent serum GM testing is less sensitive than BALF itself. Nevertheless screening of blood using GM or PCR testing detected IA cases earlier (GM: 42% or PCR: 56%), particularly when combined (GM/PCR: 73%). Therefore, regular screening facilitates and improves early detection of IA in patients suffering from acute leukemia.
Maser flares driven by variations in pumping and background radiation
Authors: Gray M D , Etoka S , Travis A , Pimpanuwat B
Published: February 2020

We simulate maser flares by varying either the pump rate or the background level of radiation in a 3D model of a maser cloud. We investigate the effect of different cloud shapes, saturation levels, and viewpoints. Results are considered for clouds with both uniform and internally variable unsaturated inversion. Pumping and background variations are represented by several different driving functions, some of which are light curves drawn from observations. We summarize the pumping variability results in terms of three observable parameters: the maximum flux density achieved, a variability index, and duty cycle. We demonstrate typical ranges of the flux density that may result from viewing an aspherical object from random viewpoints. The best object for a flare is a prolate cloud, viewed close to its long axis and driven from unsaturated conditions to at least modest saturation. Results for variation of the background level are qualitatively different from the variable pumping results in that they tend to produce short intervals of low flux density under conditions of moderate saturation and sufficient variability to be consistent with strong flaring. Variable background models typically have a significantly higher duty cycle than those with variable pumping.
Molecular cloud formation by compression of magnetized turbulent gas subjected to radiative cooling
Authors: Mandal Ankush , Federrath Christoph , Körtgen Bastian
Published: February 2020

Complex turbulent motions of magnetized gas are ubiquitous in the interstellar medium (ISM). The source of this turbulence, however, is still poorly understood. Previous work suggests that compression caused by supernova shockwaves, gravity, or cloud collisions, may drive the turbulence to some extent. In this work, we present three-dimensional (3D) magnetohydrodynamic (MHD) simulations of contraction in turbulent, magnetized clouds from the warm neutral medium of the ISM to the formation of cold dense molecular clouds, including radiative heating and cooling. We study different contraction rates and find that observed molecular cloud properties, such as the temperature, density, Mach number, and magnetic field strength, and their respective scaling relations, are best reproduced when the contraction rate equals the turbulent turnover rate. In contrast, if the contraction rate is significantly larger (smaller) than the turnover rate, the compression drives too much (too little) turbulence, producing unrealistic cloud properties. We find that the density probability distribution function evolves from a double lognormal representing the two-phase ISM, to a skewed, single lognormal in the dense, cold phase. For purely hydrodynamical simulations, we find that the effective driving parameter of contracting cloud turbulence is natural to mildly compressive (b ∼ 0.4–0.5), while for MHD turbulence, we find b ∼ 0.3–0.4, i.e. solenoidal to naturally mixed. Overall, the physical properties of the simulated clouds that contract at a rate equal to the turbulent turnover rate, indicate that large-scale contraction may explain the origin and evolution of turbulence in the ISM.
Locations of optical and γ-ray emitting regions and variation phenomena of PMN J2345−1555
Authors: Jiang Yunguo , Hu Shao-Ming , Chen Xu , Shao Xi , Huo Qiu-Hong
Published: February 2020

We collect the long-term γ-ray, optical, and radio 15 GHz light curves of quasar object PMN J2345−1555, and make correlation analyses between them. We find that different samplings can lead to different time delays, and the periodicity of light curves can produce signals that are beyond 3σ significance level. The optical V and R band and the infrared J band light curves lead the radio 15 GHz light curve by $49^{+15}_{-12}$ d. There is no lag between the optical and γ-ray light curves. We use the time lags to derive the core size and its uncertainty. We find that the core region of 15 GHz is $1.5^{+0.4}_{-0.5}$ parsec away from the jet base. The optical and γ-ray emitting regions coincide, which are located at $1.0^{+0.3}_{-0.2}$ parsec upstream of the core region of 15 GHz. Thus, the optical and γ-ray emitting regions are most probably inside the broad-line region. For this target, the magnetic field and particle density at 1 parsec in the jet are derived to be 0.16 G and 247/γmin cm−3, respectively. The black hole mass is estimated to be 108.44 M⊙. The behaviour of δV − δR is complex, while the R − J shows a bluer-when-brighter trend. We proposed an r-dependent spectral index model to explain the colour index behaviours, which is complementary for the shock in jet model. The possibility that the spectral index behaviours are due to the contribution from the disc and the varying Doppler factor is not excluded.
Triggering mixing and deceleration in FRI jets: a solution
Authors: Perucho Manel
Published: February 2020

Since Fanaroff & Riley reported the morphological and brightness dichotomy of radio galaxies, and it became clear that the symmetric emission from jets and counter-jets in the centre-brightened, less powerful, FRI sources could be caused by jet deceleration, many works have addressed different mechanisms that could cause this difference. Recent observational results seem to indicate that the deceleration must be caused by the development of small-scale instabilities that force mixing at the jet boundary. According to these results, the mixing layer expands and propagates down to the jet axis along several kiloparsecs, until it covers the whole jet cross-section. Several candidate mechanisms have been proposed as the initial trigger for the generation of such mixing layer. However, the instabilities proposed so far do not fully manage to explain the observations of FRI jets and/or require a triggering mechanism. Therefore, there is not still a satisfactory explanation for the original cause of jet deceleration. In this letter, I show that the penetration (and exit) of stars from jets could give the adequate explanation by means of creating a jet-interstellar medium mixing layer that expands across the jet.
Low Uptake of Rapid Diagnostic Tests for Respiratory Tract Infections in an Urban Safety Net Hospital
Authors: Burrowes Shana A B , Rader Alec , Ni Pengsheng , Drainoni Mari-Lynn , Barlam Tamar F
Published: February 2020

Background

Rapid diagnostic tests (RDTs) have been developed with the aim of providing accurate results in a timely manner. Despite this, studies report that provider uptake remains low.

Methods

We conducted a retrospective analysis of ambulatory, urgent care, and emergency department (ED) encounters at an urban safety net hospital with a primary diagnosis of an upper or lower respiratory tract infection (eg, bronchitis, pharyngitis, acute sinusitis) from January 1, 2016, to December 31, 2018. We collected RDT type and results, antibiotics prescribed, demographic and clinical patient information, and provider demographics.

Results

RDT use was low; a test was performed at 29.5% of the 33 494 visits. The RDT most often ordered was the rapid Group A Streptococcus (GAS) test (n = 7352), predominantly for visits with a discharge diagnosis of pharyngitis (n = 5818). Though antibiotic prescription was more likely if the test was positive (relative risk [RR], 1.68; 95% confidence interval [CI], 1.58–1.8), 92.46% of streptococcal pharyngitis cases with a negative test were prescribed an antibiotic. The Comprehensive Respiratory Panel (CRP) was ordered in 2498 visits; influenza was the most commonly detected pathogen. Physicians in the ED were most likely to order a CRP. Antibiotic prescription was lower if the CRP was not ordered compared with a negative CRP result (RR, 0.77; 95% CI, 0.7–0.84). There was no difference in prescribing by CRP result (negative vs positive).

Conclusions

RDTs are used infrequently in the outpatient setting, and impact on prescribing was inconsistent. Further work is needed to determine barriers to RDT use and to address potential solutions.
FOREST unbiased Galactic plane imaging survey with the Nobeyama 45 m telescope (FUGIN). VI. Dense gas and mini-starbursts in the W 43 giant molecular cloud complex
Authors: Kohno Mikito , Tachihara Kengo , Torii Kazufumi , Fujita Shinji , Nishimura Atsushi , Kuno Nario , Umemoto Tomofumi , Minamidani Tetsuhiro , Matsuo Mitsuhiro , Kiridoshi Ryosuke , Tokuda Kazuki , Hanaoka Misaki , Tsuda Yuya , Kuriki Mika , Ohama Akio , Sano Hidetoshi , Hasegawa Tetsuo , Sofue Yoshiaki , Habe Asao , Onishi Toshikazu , Fukui Yasuo
Published: February 2020

We performed new large-scale 12CO, 13CO, and C18O J = 1–0 observations of the W 43 giant molecular cloud complex in the tangential direction of the Scutum arm (l ∼30°) as a part of the FUGIN project. The low-density gas traced by 12CO is distributed over 150 pc × 100 pc (l × b), and has a large velocity dispersion (20–30 km s−1). However, the dense gas traced by C18O is localized in the W 43 Main, G30.5, and W 43 South (G29.96−0.02) high-mass star-forming regions in the W 43 giant molecular cloud (GMC) complex, which have clumpy structures. We found at least two clouds with a velocity difference of ∼10–20 km s−1, both of which are likely to be physically associated with these high-mass star-forming regions based on the results of high 13CO J = 3–2 to J = 1–0 intensity ratio and morphological correspondence with the infrared dust emission. The velocity separation of these clouds in W 43 Main, G30.5, and W 43 South is too large for each cloud to be gravitationally bound. We also revealed that the dense gas in the W 43 GMC has a high local column density, while “the current SFE” (star formation efficiency) of the entire GMC is low ($\sim\!\! 4\%$) compared with the W 51 and M 17 GMC. We argue that the supersonic cloud–cloud collision hypothesis can explain the origin of the local mini-starbursts and dense gas formation in the W 43 GMC complex.
Complement deposition, C4d, on platelets is associated with vascular events in systemic lupus erythematosus
Authors: Svenungsson Elisabet , Gustafsson Johanna T , Grosso Giorgia , Rossides Marios , Gunnarsson Iva , Jensen-Urstad Kerstin , Larsson Anders , Ekdahl Kristina N , Nilsson Bo , Bengtsson Anders A , Lood Christian
Published: February 2020

Objective

Complement components, including C4d, can be found on activated platelets, a process associated with vascular disease in SLE. We investigated whether platelet C4d (PC4d) adds additional value to traditional and known lupus-associated risk factors when identifying SLE patients with vascular disease.

Methods

This cross-sectional study included 308 well-characterized SLE patients and 308 matched general population controls. PC4d deposition was analysed using flow cytometry. Values >95% of controls were considered as PC4d positive (+). aPL were determined by Luminex, and the LA test was performed by DRVVT. History of vascular disease (composite and as separate outcomes) was defined at inclusion.

Results

SLE patients had increased PC4d deposition as compared with population controls (50 vs 5%, P < 0.0001). PC4d+ positively associated with any vascular events, and separately with venous and cerebrovascular events, and also with all investigated aPL profiles. The association for any vascular event remained statistically significant after adjustment for traditional and SLE-associated risk factors (odds ratio: 2.3, 95% CI: 1.3, 4.3, P = 0.008). Compared with patients negative for both PC4d and LA, patients with double positivity were more likely to have vascular disease (odds ratio: 12.3, 95% CI: 5.4, 29.3; attributable proportion due to interaction 0.8, 95% CI: 0.4, 1.1)

Conclusion

PC4d+ is associated with vascular events in SLE, independently of traditional and SLE-associated risk factors. Concurrent presence of PC4d and LA seem to interact to further increase the odds for vascular events. Prospective studies should examine whether the aPL/PC4d combination can improve prediction of vascular events in SLE and/or APS.
Genome Analysis of Melon Necrotic Spot Virus Incursions and Seed Interceptions in Australia
Authors: Mackie Joanne , Higgins Ellena , Chambers Grant A. , Tesoriero Len , Aldaoud Ramez , Kelly Geoff , Kinoti Wycliff M. , Rodoni Brendan C. , Constable Fiona E.
Published: February 2020

Melon necrotic spot virus (MNSV) was detected in field-grown Cucumis melo (rockmelon) and Citrullus lanatus (watermelon) plants in the Sunraysia district of New South Wales and Victoria, Australia, in 2012, 2013, and 2016, and in two watermelon seed lots tested at the Australian border in 2016. High-throughput sequencing was used to generate near full-length genomes of six isolates detected during the incursions and seed testing. Phylogenetic analysis of the genomes suggests that there have been at least two incursions of MNSV into Australia and none of the field isolates were the same as the isolates detected in seeds. The analysis indicated that one watermelon field sample (L10), the Victorian rockmelon field sample, and two seed interception samples may have European origins. The results showed that two isolates (L8 and L9) from watermelon were divergent from the type MNSV strain (MNSV-GA, D12536.2) and had 99% nucleotide identity to two MNSV isolates from human stool collected in the United States (KY124135.1, KY124136.1). These isolates also had high nucleotide pairwise identity (96%) to a partial sequence from a Spanish MNSV isolate (KT962848.1). The analysis supported the identification of three previously described MNSV genotype groups: EU-LA, Japan melon, and Japan watermelon. To account for the greater diversity of hosts and geographic regions of the MNSV isolates used in this study, it is suggested that the genotype groups EU-LA, Japan melon, and Japan watermelon be renamed to groups I, II, and III, respectively. The divergent isolates L8 and L9 from this study and the stool isolates from the United States formed a fourth genotype group, group IV. Soil collected from the site of the Victorian rockmelon MNSV outbreak was found to contain viable MNSV and the virus vector, a chytrid fungus, Olpidium bornovanus (Sahtiyanci) Karling, 18 months after the initial MNSV detection. This is a first report of O. bornovanus from soil sampled from an MNSV-contaminated site in Australia.
Characterization of Pyrenophora Species Causing Brown Leaf Spot on Italian Ryegrass (Lolium multiflorum) in Southwestern China
Authors: Xue Longhai , Liu Yong , Zhou Su , White James F. , Li Chunjie
Published: February 2020

Drechslera leaf spot (DLS) caused by Pyrenophora (Drechslera) species is one of the most serious diseases affecting Italian ryegrass (Lolium multiflorum) in China. Between 2015 and 2018, this disease was observed in three Italian ryegrass fields in the province of Sichuan, China. Average leaf disease incidence was approximately 1 to 12% but could range up to 100%. Symptoms appeared as brown or tan spots surrounded by a yellow halo, or brown to dark brown net blotch; subsequently, spots increased in number and size, and they later covered a large area of leaf, eventually causing leaf death. In this study, 86 strains of Pyrenophora fungi were isolated from leaf lesions of Italian ryegrass. Coupled with phylogenetic analysis of the internal transcribed spacer region, partial 28S ribosomal RNA gene, and glyceraldehyde-3-phosphate dehydrogenase gene, morphological characteristics showed that Pyrenophora dictyoides and P. nobleae are associated with Italian ryegrass in southwest China. Pathogenicity tests confirmed that both species can infect Italian ryegrass, causing leaf spot, whereas the virulence of the two species differed; P. nobleae showed lower pathogenicity to Italian ryegrass. This is the first time that these two Pyrenophora species were formally reported on Italian ryegrass based on both morphological and molecular characters. Overall, this study improves knowledge of the Pyrenophora species associated with Italian ryegrass and provides a foundation for control of this disease in the future.
The Effect of Tractor Speed and Canopy Position on Fungicide Spray Deposition and Peach Scab Incidence and Severity
Authors: Bock Clive H. , Rains Glen C. , Hotchkiss Mike W. , Chen Chunxian , Brannen Phil M.
Published: February 2020

Peach scab, caused by Venturia carpophila, is a damaging disease of peach in the southeastern United States. Thus, fungicides are applied to reduce peach scab. Tractor speed was investigated as a variable affecting spray deposition and disease control in relation to volume applied. In experiments in 2015 and 2016, trees were sprayed with fungicide to control scab at petal fall to 1% shuck split and at shuck split to 10% shuck off. Speeds were 3.2, 4.8, and 6.4 kph resulting in 1,403, 935, and 701 liters/ha, respectively, with the dose of active ingredient (a.i.) per ha kept constant. Deposition declined for all speeds with later spray dates. There was a negative linear relationship between tractor speed and spray coverage on three of four dates the experiment was repeated. Tractor speed (different volumes, equal doses) affected peach scab. In 2015 and 2016, mean incidence at 3.2, 4.8, and 6.4 kph was 68.6, 59.2, and 38.3%, and 64.2, 53.0, and 40.4% of fruit scabbed, respectively. Effect of speed on lesion number per fruit depended on year: in 2015, lesions per fruit were reduced at 6.4 kph compared with 3.2 and 4.8 kph but were not different in 2016. Control trees had fewer lesions per fruit high in the canopy, but there was little effect of sample height in fungicide-treated trees. Concentration of a.i. in lower volumes applied at higher speed may provide some benefit in reducing incidence of peach scab, but there appeared to be less effect on severity.
Pseudomonas synxantha 2-79 Transformed with Pyrrolnitrin Biosynthesis Genes Has Improved Biocontrol Activity Against Soilborne Pathogens of Wheat and Canola
Authors: Zhang Jibin , Mavrodi Dmitri V. , Yang Mingming , Thomashow Linda S. , Mavrodi Olga V. , Kelton Jason , Weller David M.
Published: February 2020

A four-gene operon (prnABCD) from Pseudomonas protegens Pf-5 encoding the biosynthesis of the antibiotic pyrronitrin was introduced into P. synxantha (formerly P. fluorescens) 2-79, an aggressive root colonizer of both dryland and irrigated wheat roots that naturally produces the antibiotic phenazine-1-carboxylic acid and suppresses both take-all and Rhizoctonia root rot of wheat. Recombinant strains ZHW15 and ZHW25 produced both antibiotics and maintained population sizes in the rhizosphere of wheat that were comparable to those of strain 2-79. The recombinant strains inhibited in vitro the wheat pathogens Rhizoctonia solani anastomosis group 8 (AG-8) and AG-2-1, Gaeumannomyces graminis var. tritici, Sclerotinia sclerotiorum, Fusarium culmorum, and F. pseudograminearum significantly more than did strain 2-79. Both the wild-type and recombinant strains were equally inhibitory of Pythium ultimum. When applied as a seed treatment, the recombinant strains suppressed take-all, Rhizoctonia root rot of wheat, and Rhizoctonia root and stem rot of canola significantly better than did wild-type strain 2-79.
Exocrine pancreatic insufficiency
Authors: Bellomo Tamara L.
Published: February 2020

Exocrine pancreatic insufficiency (EPI) prevents the pancreas from making enough of the exocrine pancreatic enzymes that help the body digest food. EPI can be challenging to recognize and diagnose because many of its signs and symptoms overlap with other gastrointestinal disorders. This article offers practical advice to nurses for patient assessment and nursing interventions.
Changes in hot flash experiences and related factors in women with breast cancer
Authors: Li Chia-Ying , Lin Yung-Chang , Yang Tsui-Yun , Chen Shin-Cheh , Chang Hsien-Kun , Shen Wen-Chi , Chen Mei-Ling
Published: February 2020

Objective:

Taiwanese women are younger than women in western countries when diagnosed with breast cancer, and many of them are still menstruating. One of many distressing side effects reported by premenopausal women treated for breast cancer are hot flashes (HFs). The purposes of this study were to identify: (1) the trajectories of hot flash (HF) occurrence, frequency, and interference and (2) potential factors associated with HF changes.

Methods:

Peri- or premenopausal women newly diagnosed with breast cancer scheduled to receive chemotherapy and hormonal therapy were enrolled. HF frequency, HF interference, and other symptoms were measured six times from prechemotherapy to 24 months after chemotherapy. Data were analyzed using hierarchical linear modeling.

Results:

A total of 90 women were eligible for the study. The prechemotherapy occurrence rate of HFs was 7.9%, but rapidly increased to 42.5% immediately after chemotherapy. The change curve of HF frequency and interference appeared quadratic, increasing first and slightly decreasing later. At any time point, increased body mass index (BMI) was associated with both higher HF frequency (P = 0.020) and HF interference (P = 0.002), whereas anxiety (P < 0.001) and loss of sexual desire (P = 0.038) were associated with higher HF interference. Six months after completing chemotherapy, premenopausal women reported significantly higher HF frequency than perimenopausal women (P = 0.041).

Conclusion:

A significant proportion of pre- and perimenopausal women experienced HFs after receiving breast cancer treatment. Our findings on HF trajectories can educate patients newly diagnosed with breast cancer. Special attention should be paid to those with increased body mass index changes and those still regularly menstruating.
MsFLASH network vaginal health trial: absence of evidence is NOT evidence of absence
Authors: Lukas Vanessa A. , Simon James A.
Published: February 2020

Approximately 50% of postmenopausal women experience vulvovaginal symptoms associated with genitourinary syndrome of menopause (GSM). GSM is a chronic and progressive condition with a well-defined treatment algorithm. Analysis of the MsFLASH Vaginal Health Trial data produced two main conclusions, which were that prescribed vaginal 10 μg estradiol tablet and over-the-counter (OTC) vaginal moisturizer did not provide additional benefit over placebo vaginal tablet and placebo gel in reducing postmenopausal vulvovaginal symptoms; or increasing the proportions of women reporting sexual activity or improving pain scores with sexual activity. These treatment conclusions are contrary to all prior robust clinical trial data for dyspareunia and vaginal dryness, and not in line with the good clinical practice for GSM management presented by the American College of Obstetricians and Gynecologists, The North American Menopause Society, and the Endocrine Society. Overall, the flaws of the MsFLASH Vaginal Health Trial were to incorrectly identify the therapeutic outcomes of most interest using metrics that exhibit high degrees of placebo bias; and to utilize low statistical power with which to appreciate any significant differences between groups.
Regression of Keratoconus After Gastric Sleeve Surgery
Authors: Greenberg Jeremy R. , McCormick Gregory J.
Published: February 2020

Purpose:

To report a case of regression of keratoconus by corneal topography after gastric sleeve surgery.

Methods:

Case report.

Results:

A patient with a history of bilateral progressive keratoconus was observed before and after bariatric surgery for morbid obesity. His left eye had a history of penetrating keratoplasty for advanced keratoconus, and his right eye had active progression of keratoconus in the years before sleeve gastrectomy. After the surgery, the right eye showed significant corneal flattening over a period of 2 years. This was especially pronounced at the apex of the cone (∼5 D). The patient's best spectacle-corrected visual acuity also improved along with management of his obesity and type 2 diabetes mellitus.

Conclusions:

This is the first report of regression of keratoconus after bariatric surgery.
Update on the management of acute liver failure
Authors: Jayalakshmi Vadivukkarasi T. , Bernal William
Published: February 2020

Purpose of review

The aim of this article is to provide the reader with an overview of established standards of care and to summarize important newer research findings in acute liver failure (ALF).

Recent findings

New international guidelines are now in place with recommendations for medical care and nutritional support. Large-scale retrospective studies have confirmed the low level of bleeding complications observed, despite apparently severe coagulopathy on standard laboratory testing, and the improved survival seen with continuous rather than intermittent forms of renal replacement therapy. Advances in neurologic support include confirmation of the efficacy of control of hyperammonaemia using continuous haemofiltration, and of the utility of transcranial Doppler ultrasound as a screening modality for detection of cerebral oedema. Improvements in outcomes with medical treatment for some causes of ALF have resulted in need for new means of identification of patients who will benefit from liver transplantation.

Best practice in the care of patients with ALF continues to evolve with ongoing improvement in survival. Survival in these patients is expected to improve further with refinement of medical supportive care and more accurate identification of transplant candidacy.
Eyeing up the injured brain: automated pupillometry and optic nerve sheath diameter
Authors: Romagnosi Federico , Bongiovanni Filippo , Oddo Mauro
Published: February 2020

Purpose of review

Multimodal monitoring has emerged as a novel paradigm of care in acute brain injury, and in this context the value of noninvasive devices is increasingly under scrutiny. This narrative review summarizes recent clinical investigation focused on the role of automated infrared pupillometry (AIP) and optic nerve sheath diameter (ONSD) ultrasound as novel techniques to monitor and manage neurocritical care patients.

Recent findings

AIP provides a quantitative measurement of the pupillary light reflex that is more precise and reliable than the traditional examination of the pupillary light reflex using manual flashlight lamps. AIP helps detect raised intracranial pressure (ICP) and brain herniation in patients with intracranial mass lesions. Using an automatically computed scalar index – the neurological pupil index – AIP has great accuracy to predict poor neurological outcome in patients in coma after cardiac arrest. Recent data indicate that ONSD may diagnose intracranial hypertension with better accuracy than other ultrasound-based methods.

Noninvasive AIP and ONSD appear useful complements to multimodality monitoring of acute brain injury, in particular in patients at risk of elevated ICP and for early neuroprognostication following cardiac arrest.