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Dust grains have been used as minimally invasive probes to determine plasma parameters including the plasma density, temperature, and electric field in a plasma discharge. However, the dust grains in a plasma generate local potential disturbances due to the collection of charge and the subsequent electrostatic interactions between the dust and charged plasma particles. Dust grains in close proximity to one another exhibit interesting non-reciprocal interactions and self-organize into structures such as one-dimensional filamentary chains, two-dimensional "zigzags," and three-dimensional helices, among others. The formation of these structures suggests that although the dust grains may be less invasive than traditional plasma probes, the disturbance to the local plasma environment introduced by dust grains is non-trivial. Commonly used analytic forms of the electric potential describing complex plasmas have failed to resolve the near-dust region, and as a result are insufficient to provide insight about the formation of complex dust structures. Here, we use an N-body simulation to compute the electric potential from ion densities near various dust grain configurations. We provide an alternative description to the standard analytic model for the electric potential of dust and ion wakes based on a Gaussian shaped cloud of ions. The electric potential obtained from simulations is used to identify minimum energy configurations for two and three dust grains. It is further demonstrated that the minimum potential region identified for N dust grains and their associated ion wakes does not predict the minimum-energy configuration of N + 1 dust grains. [ABSTRACT FROM AUTHOR]

This document is an erratum for a paper titled "Interacting dust grains in complex plasmas: Ion wake formation and the electric potential." The authors acknowledge a misprint in Figure 9 of their paper, where subplots (i)–(aa) were mistakenly printed out of order. The error occurred during the review process, and the corrected Figure 9 is presented as Figure 1 in the erratum. The authors assure that all the conclusions of the paper remain unaffected. The work was supported by the National Science Foundation, the U.S. Department of Energy, and the NVIDIA Corporation's Applied Research Accelerator Program. [Extracted from the article]

Trichothecenes are toxins produced by certain species from several fungal genera, including Aspergillus, Fusarium, Isaria, Paramyrothecium, Stachybotrys, Trichoderma, and Trichothecium. These toxins are of interest because they contribute to the toxigenicity, plant pathogenicity, and/or biological control activities of some fungi. All trichothecenes have the same core (12,13-epoxytrichothec-9-ene or EPT) structure but can differ from one another by the presence or absence of a macrocyclic ring formed from polyketide and isoprenoid substituents esterified to carbon atoms 4 and 15 of EPT, respectively. Genes required for formation and some modifications of EPT have been elucidated, but almost nothing is known about genes specific to the formation of the macrocyclic ring. Therefore, we used genomic, transcriptomic, metabolomic, and gene deletion analyses to identify genes that are required specifically for the formation of the macrocyclic ring. These analyses identified one gene, TRI24, that is predicted to encode an acyltransferase and that is required for macrocyclic ring formation during biosynthesis of macrocyclic trichothecenes by the fungus Paramyrothecium roridum. In addition, a TRI24 deletion mutant of P. roridum caused less severe disease symptoms on common bean and had less antifungal activity than its wild-type progenitor strain. We propose that the reduced aggressiveness and antifungal activity of the mutant resulted from its inability to produce trichothecenes with a macrocyclic ring. To our knowledge, this is the first report of a gene required specifically for the formation of the macrocyclic ring of trichothecenes and that loss of the macrocyclic ring of trichothecenes can alter the biological activities of a fungus. KEY POINTS: • TRI24 gene is found in all known macrocyclic trichothecene-producing fungi. • A tri24-deletion mutant exhibits a reduction in antifungal and plant disease activities. • TRI24 is the first described gene specific to macrocyclic trichothecene biosynthesis., (© 2024. The Author(s).)

Central nervous system (CNS) injury is common in sickle cell disease (SCD) and occurs early in life. Hydroxyurea is safe and efficacious for treatment of SCD, but high-quality evidence from randomized trials to estimate its neuroprotective effect is scant. HU Prevent was a randomized (1:1), double-blind, phase II feasibility/pilot trial of dose-escalated hydroxyurea vs. placebo for the primary prevention of CNS injury in children with HbSS or HbS-β 0 -thalassemia subtypes of SCD age 12-48 months with normal neurological examination, MRI of the brain, and cerebral blood flow velocity. We hypothesized that hydroxyurea would reduce by 50% the incidence of CNS injury. Two outcomes were compared: primary-a composite of silent cerebral infarction, elevated cerebral blood flow velocity, transient ischemic attack, or stroke; secondary-a weighted score estimating the risk of suffering the consequences of stroke (the Stroke Consequences Risk Score-SCRS), based on the same outcome events. Six participants were randomized to each group. One participant in the hydroxyurea group had a primary outcome vs. four in the placebo group (incidence rate ratio [90% CI] 0.216 [0.009, 1.66], p = .2914) (~80% reduction in the hydroxyurea group). The mean SCRS score was 0.078 (SD 0.174) in the hydroxyurea group, 0.312 (SD 0.174) in the placebo group, p = .072, below the p-value of .10 often used to justify subsequent phase III investigations. Serious adverse events related to study procedures occurred in 3/41 MRIs performed, all related to sedation. These results suggest that hydroxyurea may have profound neuroprotective effect in children with SCD and support a definitive phase III study to encourage the early use of hydroxyurea in all infants with SCD., (© 2024 Wiley Periodicals LLC.)

We analyzed our challenging experience with a randomized controlled trial of misoprostol for prevention of recurrent C. difficile. Despite careful prescreening and thoughtful protocol modifications to facilitate enrollment, we closed the study early after enrolling just 7 participants over 3 years. We share lessons learned, noting the importance of feasibility studies, inclusion of biomarker outcomes, and dissemination of such findings to inform future research design and implementation successes., Competing Interests: Declaration of competing interest S.K.M.: Research funding from Finch Therapeutics. E.R.D: Research funding provided by Ferring, Synthetic Biologics, and Pfizer; Consultant for Summit, Seres, Abbott, Pfizer, Merck, Ferring., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Although significant amounts of polymers associated with adverse health effects in oils are produced during frying, the chemical bonds forming these polymers are not well understood. This study revealed that ester bonds are responsible for the polymerization of soybean oil during frying and heating at 175 °C. The ester value of soybean oil increased during frying up to day 3 of the experiment and slightly decreased on day 4 of the experiment indicating that esterification and hydrolysis concomitantly occurred. The 13 C NMR spectra showed further evidence of the formation of ester bonds. This study also examined unidentified chemical bonds in the polymer products, other than ester bonds, with NMR spectroscopy. No NMR signals indicating ether bonds were observed. The NMR study after the reaction of oxidized soybean oil with acetyl chloride clarified assignments of proton signals, confirming some previous assignments, and assigning a new proton signal as an alcohol., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Fungal entomopathogens are potential tools for the control of mosquito vectors that transmit infectious agents that cause disease in humans and animals. During the infection process, effective recognition of the invading fungi by the mosquito, is a crucial step in mounting an appropriate anti-fungal response. In this study, we investigated the role of peptidoglycan recognition receptors (PGRPs) in host resistance to fungal entomopathogens at the early stages of infection. Our study identified the induction of PGRP-LA, -LB, -LD, -LE , and -S1 during infection with two different fungal entomopathogenic strains. Furthermore, our data shows temporal differences in PGRP elicitation, with most PGRPs displaying significant upregulation at 60 h post-infection. Depletion of certain PGRPs via RNAi silencing resulted in a significant increase in fungal proliferation and a reduction in mosquito survival that was fungal strain-specific. Our data indicates that PGRPs play an important role in the antifungal response and expands our understanding of the factors that determine host susceptibility to fungal entomopathogens., (Copyright © 2020 Ramirez, Muturi, Flor-Weiler, Vermillion and Rooney.)

Rising atmospheric CO 2 concentrations and associated climate changes are thought to have contributed to the steady increase of Fusarium head blight (FHB) on wheat. However, our understanding of precisely how elevated CO 2 influences the defense response of wheat against Fusarium graminearum remains limited. In this study, we evaluated the metabolic profiles of susceptible (Norm) and moderately resistant (Alsen) spring wheat in response to whole-head inoculation with two deoxynivalenol (DON)-producing F. graminearum isolates (DON + ), isolates 9F1 and Gz3639, and a DON-deficient (DON - ) isolate (Gzt40) at ambient (400 ppm) and elevated (800 ppm) CO 2 concentrations. The effects of elevated CO 2 were dependent on both the Fusarium strain and the wheat variety, but metabolic differences in the host can explain the observed changes in F. graminearum biomass and DON accumulation. The complexity of abiotic and biotic stress interactions makes it difficult to determine if the observed metabolic changes in wheat are a result of CO 2 -induced changes in the host, the pathogen, or a combination of both. However, the effects of elevated CO 2 were not dependent on DON production. Finally, we identified several metabolic biomarkers for wheat that can reliably predict FHB resistance or susceptibility, even as atmospheric CO 2 levels rise.

Background: Studies of interventions to prevent the many neurological complications of sickle cell disease must take into account multiple outcomes of variable severity, with limited sample size. The goals of the studies presented were to use investigator preferences across outcomes to determine an attitude-based weighting of relevant clinical outcomes and to establish a valid composite outcome for a clinical trial., Methods: In Study 1, investigators were surveyed about their practice regarding hydroxyurea therapy and opinions about outcomes for the "Hydroxyurea to Prevent the Central Nervous System Complications of Sickle Cell Disease Trial" (HU Prevent), and their minimally acceptable relative risk reduction for the two outcome components, motor and neurocognitive deficits. In Study 2, HU Prevent investigators provided overall weights for these two components. In Study 3, they provided more granular rankings, ratings, and maximum number acceptable to harm. A weighted composite outcome, the Stroke Consequences Risk Score, was constructed that incorporates the major neurologic complications of sickle cell disease. The Stroke Consequences Risk Score represents the 3-year risk of suffering the adverse consequences of stroke. In Study 4, the results of the Optimizing Primary Stroke Prevention in Sickle Cell Anemia (STOP2) and Silent Infarct Transfusion Trials were reanalyzed in light of the composite outcome., Results: In total, 22 to 27 investigators participated per study. In Study 1, across three samplings between 2009 and 2015, the average minimally acceptable relative risk reduction ranged from 0.36 to 0.50, at or below the target effect size of 0.50. In 2015, 21 (91%) reported that a placebo-controlled trial is reasonable; 23 (100%), that it is ethical; and 22 (96%), that they would change their practice, if the results of the trial were positive. In Studies 2 and 3, the weight elicited for a cognitive decline (of 10 IQ points) from the overall assessment was 0.67 (and for motor deficit, the complementary 0.33); from ranking, 0.6; from rating, 0.58; and from maximal number acceptable to harm, 0.5. Using data from two major clinical trials, Study 4 demonstrated the same conclusions as the original trials using the Stroke Consequences Risk Score, with smaller p-values for both reanalyses. An assessment of acceptability was performed as well., Conclusion: This set of studies provides the rationale, justification, and validation for the use of a weighted composite outcome and confirms the need for the phase III HU Prevent study. Surveys of investigators in multi-center studies can provide the basis of clinically meaningful outcomes that foster the translation of study results into practice while increasing the efficiency of a study.

Objective: Colorectal cancer (CRC) incidence is higher in African Americans (AAs) compared with non-Hispanic whites (NHWs). A diet high in animal protein and fat is an environmental risk factor for CRC development. The intestinal microbiota is postulated to modulate the effects of diet in promoting or preventing CRC. Hydrogen sulfide, produced by autochthonous sulfidogenic bacteria, triggers proinflammatory pathways and hyperproliferation, and is genotoxic. We hypothesised that sulfidogenic bacterial abundance in colonic mucosa may be an environmental CRC risk factor that distinguishes AA and NHW., Design: Colonic biopsies from uninvolved or healthy mucosa from CRC cases and tumour-free controls were collected prospectively from five medical centres in Chicago for association studies. Sulfidogenic bacterial abundance in uninvolved colonic mucosa of AA and NHW CRC cases was compared with normal mucosa of AA and NHW controls. In addition, 16S rDNA sequencing was performed in AA cases and controls. Correlations were examined among bacterial targets, race, disease status and dietary intake., Results: AAs harboured a greater abundance of sulfidogenic bacteria compared with NHWs regardless of disease status. Bilophila wadsworthia -specific dsrA was more abundant in AA cases than controls. Linear discriminant analysis of 16S rRNA gene sequences revealed five sulfidogenic genera that were more abundant in AA cases. Fat and protein intake and daily servings of meat were significantly higher in AAs compared with NHWs, and multiple dietary components correlated with a higher abundance of sulfidogenic bacteria., Conclusions: These results implicate sulfidogenic bacteria as a potential environmental risk factor contributing to CRC development in AAs., Competing Interests: Competing interests: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Additives were evaluated to investigate their effects on volatility of sesamol at frying temperature with the hypothesis that the interaction between an additive and sesamol would reduce sesamol volatility. Twenty-two additive : sesamol combinations were examined by thermogravimetric analysis (TGA) under nitrogen in neat form and in soybean oil. The results indicate that these additives could bind to or interact with sesamol and consequently reduced its volatility. (1) H NMR study provided evidence for hydrogen bonding between sesamol and a hydroxyl group, an amino group, and ether groups. Subsequent heating tests were conducted to investigate the effect of the reduced volatility of sesamol on antioxidant activity in soybean oil at 180 °C. Oxidation of soybean oil was monitored with gel permeation chromatography for formation of polymerized triacylglycerols and with (1) H NMR for loss of olefinic and bisallylic protons. Sesamol retained in soybean oil during the heating process was determined by high-performance liquid chromatography. A strong correlation between the retained sesamol and the antioxidant activity was observed. The mixture of 830 ppm sesamol and mono-/diglycerides, polysorbate 20 or l-carnosine showed much improved antioxidant activity compared to sesamol itself and slightly better antioxidant activity than 200 ppm tert-butylhydroquinone. It is believed that this method can also be used for many other antioxidants for which volatility is a problem., (Published 2014. This article is a U.S. Government work and is in the public domain in the USA.)

The braconid wasp, Spathius agrili, has been released in the U.S. as a biocontrol agent for the invasive emerald ash borer (Coleoptera: Buprestidae: Agrilus planipennis), a destructive pest of ash trees (Fraxinus spp.). We identified and synthesized seven male-specific volatile compounds. Three of these, dodecanal, (4R,11E)-tetradecen-4-olide, and (Z)-10-heptadecen-2-one, were the key behaviorally active components in flight tunnel bioassays. Male specificity was demonstrated by gas chromatographic comparison of male and female volatile emissions and whole body extracts. Identifications were aided by coupled gas chromatographic-mass spectrometric (GC-MS) analysis, microchemical reactions, NMR, chiral GC analysis, and GC and MS comparison with authentic standards. Both the racemic and chiral forms of the γ-lactone, as well as both E- and Z-isomers were synthesized. Flight tunnel behavioral tests showed positive male and female S. agrili responses to both natural pheromone and synthetic blends, with upwind flight and landing on the source. Large field-cage tests, using yellow sticky traps baited with pheromone, captured approximately 50% of the released male and female wasps in 24-h periods. The use of pheromone-baited traps in the field could simplify the current detection method for determining parasitoid establishment (i.e., laboriously felling and peeling ash trees for recovery of S. agrili from infested EAB larvae).

Scope: The biological functions of caffeoylquinic acid (CQA) derivatives from various plant sources have been partially elucidated. The objectives were to isolate and purify diCQAs from Yerba mate tea leaves and assess their anti-inflammatory and anti-cancer capabilities in vitro and explore their mechanism of action., Methods and Results: Methanol extracts of dried mate leaves were resolved by flash chromatography and further purified resulting in two fractions one containing 3,4- and 3,5-diCQAs and the other 4,5-diCQA with NMR-confirmed structures. Both fractions inhibited LPS-induced RAW 264.7 macrophage inflammation by suppressing nitric oxide/inducible nitric oxide and prostaglandin E(2) /cyclooxygenase-2 pathways through inhibiting nucleus translocation of Nuclear factor κB subunits, p50 and p65. The diCQA fractions inhibited Human colon cancer cells CRL-2577 (RKO) and HT-29 cell proliferation by inducing apoptosis in a time- and concentration-dependent manner, but did not affect the protein levels of p21, p27, p53, and Bax:Bcl-2 ratio in RKO cells. In HT-29 cells, however, the diCQA fractions increased Bax:Bcl-2 ratio. The diCQA fractions increased the activation of caspase-8 leading to cleavage of caspase-3 in both RKO and HT-29 colon cancer cells., Conclusion: The results suggest that diCQAs in Yerba mate could be potential anti-cancer agents and could mitigate other diseases also associated with inflammation., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Phosphonate reagents were developed for the two-carbon homologation of aldehydes or ketones to unbranched- or methyl-branched α,β-unsaturated aldehydes. The phosphonate reagents, diethyl methylformyl-2-phosphonate dimethylhydrazone and diethyl ethylformyl-2-phosphonate dimethylhydrazone, contained a protected aldehyde group instead of the usual ester group. A homologation cycle entailed condensation of the reagent with the starting aldehyde, followed by removal of the dimethylhydrazone protective group with a biphasic mixture of 1 M HCl and petroleum ether. This robust two-step process worked with a variety of aldehydes and ketones. Overall isolated yields of unsaturated aldehyde products ranged from 71% to 86% after the condensation and deprotection steps.

Most industrial lubricants are derived from nonrenewable petroleum-based sources. As useful as these lubricants are, their unintended consequences are the pollution of the Earth's environment as a result of the slow degradation of the spent materials. Native seed oils, on the other hand, are renewable and are also biodegradable in the environment, but these oils often suffer a drawback in having lower thermal stability and a shorter shelf life because of the intrinsic -C═C- unsaturation in their structures. This drawback can be overcome, yet the inherent biodegradative property retained, by appropriate derivatization of the oil. Pursuant to this, this study investigated derivatized polyhydroxy milkweed oil to assess its suitability as lubricant. The milkweed plant is a member of the Asclepiadaceae, a family with many genera including the common milkweeds, Asclepias syriaca L., Asclepias speciosa L., Asclepias tuberosa L., etc. The seeds of these species contain mainly C-18 triglycerides that are highly unsaturated, 92%. The olefinic character of this oil has been chemically modified by generating polyhydroxy triglycerides (HMWO) that show high viscosity and excellent moisturizing characteristics. In this work, HMWO have been chemically modified by esterifying their hydroxyl groups with acyl groups of various chain lengths (C2-C5). The results of investigation into the effect of the acyl derivatives' chemical structure on kinematic and dynamic viscosity, oxidation stability, cold-flow (pour point, cloud point) properties, coefficient of friction, wear, and elastohydrodynamic film thickness are discussed.

Flea beetles in several genera are known to possess male-specific sesquiterpenes, at least some of which serve as aggregation pheromones that attract both sexes. In continuing research on the chemical ecology of Phyllotreta flea beetles, six new male-specific sesquiterpenes were identified, one from P. striolata (hydroxyketone 9) and five from P. pusilla (aldehydes 10-12 and 14 and alcohol 13); both species are crop pests. The minute amounts from beetles provided mass spectra and chromatographic data but were insufficient for complete structure determination. However, it was discovered that the new compounds could all be produced by applying organic reactions to previously identified flea beetle sesquiterpenes, and the resulting, larger amounts of material permitted definitive structure analysis by NMR. Molecular modeling was used in conjunction with NMR to define relative configurations of several newly created stereogenic centers. The absolute configurations of natural 9-14 were established by chiral gas chromatography/mass spectrometry. In electrophysiological tests (GC-EAD) conducted with P. striolata, compound 9 was detected with high sensitivity by the beetle antennae, which is consistent with a pheromonal function. The research opens new possibilities for using behavioral chemicals to monitor or manage these pest species.

This paper describes the preparation of a new type of branched vegetable oil and its methyl ester that involves the formation of acetonides. A facile and environmentally friendly synthesis has been found to produce acetonides that entails the use of ferric chloride as a catalyst and is conducted at room temperature. The products have been fully characterized with the help of model compounds, including elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR), and gas chromatography-mass spectrometry (GC-MS).

A new withanolide, dinoxin B (12,21-dihydroxy-1-oxowitha-2,5,24-trienolide-27-O-β-D-glucopyranoside, 1), was isolated from a methanol extract of Datura inoxia leaves, using bioassay-guided fractionation. The structure was determined by spectroscopic techniques, including (1)H, (13)C, and 2D NMR experiments as well as by HRMS. Extracts and the purified compound were tested for their antiproliferative activities toward a panel of human normal and cancer cell lines. Dinoxin B (1) and its aglycone (2) exhibited submicromolar IC(50) values against multiple human cancer cell lines. Among the most sensitive were several breast cancer cell lines. Dinoxin B (1) was found only in D. inoxia and was not detected in D. metel or D. stramonium. The accumulation of this compound was limited largely to leaf tissue, with little to none detected in extracts from the flowers, fruits, roots, or stems of D. inoxia.

In FY09, as a result of an initiative to improve net income, reduce expenses, and enhance revenue cycle processes, in which leaders' goals were tied to the financial performance of the organization, Baptist Health Care achieved: A $17 million increase in net operating income. A $9.2 million reduction in operating costs. Patient satisfaction levels in the 97th percentile. A coding accuracy rate of 99 percent. A more than $1 million increase in point-of-service collections.

The feasibility of obtaining high quality homonuclear or heteronuclear diffusion-ordered (13)C NMR data is shown to be greatly improved by using (13)C isotopically-enriched samples. Stable isotope-enhanced diffusion ordered (SIE-DOSY) (13)C NMR has been applied to (13)C-enriched carbohydrates, and has been used to determine diffusion coefficients for pentose and hexose monosaccharides, and a disaccharide and trisaccharide. These 2D spectra were obtained with as little as 8 min of acquisition time. Fully resolved 3D DOSY-HMQC NMR spectra of [U-(13)C]xylose, [U-(13)C]glucose, and [1-(13)C(gal)]lactose were obtained in 5h. Sample derivatization with [carbonyl-(13)C]acetate (peracetylation) extends the usefulness of the technique to included non-labeled sugars; the (13)C-carbonyl - carbohydrate ring proton (1)H-(13)C correlations also provide additional structural information, as shown for the 3-D DOSY-HMQC analysis of a mixture of maltotriose and lactose per-[carbonyl-(13)C]acetates.

MALDI-TOFMS approaches have been developed for high-throughput screening of naturally occurring mixtures of rhamnolipids from Pseudomonas spp. Monorhamnolipids and dirhamnolipids are readily distinguished by characteristic molecular adduct ions, [M+Na](+) and [M-H+Na(2)](+), with variously acylated rhamnolipids differing by 28 mu. Following proton-deuterium exchange, deuterated [M+Na-4(1)H+4(2)H](+) and [M+Na-6(1)H+6(2)H](+) ions are observed for the monorhamnolipids and dirhamnolipids, respectively, which allows rapid identification of these molecules. The described approach has been validated by compositional analysis using GC/MS, fractionation by RPHPLC, and analysis by 1D and 2D NMR spectroscopy. MALDI-TOFMS analysis allows the rapid screening of variously acylated rhamnolipids, and has potential for selective identification of new surfactants from microbial strains.

Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2 E,4 E,6 Z) and (2 E,4 E,6 E) isomers as components of its male-produced aggregation pheromone. Here, we learned that the related species, E. hirtipennis, also emits a blend of 2,4,6-nonatrienals, including isomers not previously characterized. Patterns in emission and response suggest a pheromonal function. In an effort to acquire standards to aid in identification, we found that exposing (2 E,4 E,6 E)-2,4,6-nonatrienal (or other available 2,4,6-nonatrienals) to light readily generated a mixture of six geometrical isomers. Configurations of these were determined by NMR, and chromatographic properties (GC and HPLC) were documented. On the basis of chromatographic comparison to these standards, the most abundant, new compound from E. hirtipennis was concluded to be (2 E,4 Z,6 Z)-2,4,6-nonatrienal. Minor components from both E. hirtipennis and E. fuscula were also characterized. The analytical approach given here would also be of use in the food industry, where 2,4,6-nonatrienals are important as aroma compounds.