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The two-spotted lady beetle, Adalia bipunctata L., displays warning colouration that is reinforced by the production of adaline and adalinine. These alkaloids are thought to provide defense against predation throughout all life stages of A. bipunctata and may play a role in the insect immune system. Vairimorpha (Nosema) adaliae, a microsporidium described from A. bipunctata, has minimal effects on its host (delayed larval development) when reared under optimum conditions but stress factors are shown to affect the development of microsporidiosis. The objectives of this study were to determine the effects of V. adaliae on relative alkaloid content (adaline) during A. bipunctata development, and to evaluate the combined effects of physical stress and infection on adult beetles (relative alkaloid content and infection load). First-instar larvae were isolated from uninfected and V. adaliae-infected colonies. Eggs and first-instar larvae were immediately prepared for alkaloid analysis, whereas late-instar larvae, pupae and adults were systematically processed when each reached their designated developmental stage. Upon eclosion, a subsample of beetles was exposed to varying amounts of physical agitation: control (no shaking), alternate shaking (every other day), and daily shaking. Immediately following these stress trials, alkaloid samples were collected for analysis and spore loads were assessed. Overall, relative adaline proportions increased from egg to adult. Uninfected individuals had significantly higher relative proportions of adaline than did infected individuals during early development; however, adaline content was higher in infected A. bipunctata from the third-instar onwards, when compared to their uninfected counterparts. Following exposure to physical agitation on alternate days, uninfected adults had a significantly higher relative proportion of adaline than did infected adults. Interestingly, exposure to different levels of agitation had no significant effect on alkaloid production for either uninfected or infected beetles. Mean spore counts were significantly higher for adults that were exposed to daily shaking when compared to individuals from the control and alternate shaking groups. From a biological perspective, one would expect to observe differences in alkaloid production through coccinellid development, as each successive life stage faces different external pressures and risks. When infected with the microsporidium V. adaliae, however, adaline production was reduced during early development but increased significantly in late life stages., 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., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The partition constants ( p -values) of primary alcohols in solutions containing aggregates of symmetric gemini surfactants of the family N , N '-dimethyl, N -dialkyl- α , ω -alkanediammonium dibromide (m-s-m = symmetric gemini surfactants) have been computed from the measured values of their diffusion coefficients obtained from NMR-diffusion experiments. From the p -values, both mole-fraction and concentration-based partition coefficients and Gibbs energies of transfer for the alcohols from the bulk D 2 O phase to the gemini aggregate phase have been calculated. As expected, the Gibbs energy of transfer decreased linearly with an increase in the alcohol carbon length for each of the primary alcohol/gemini amphiphile series studied. The Gibbs transfer energy increment per CH 2 for the alcohols was consistent for all the alcohol/gemini amphiphile series and was in excellent agreement with the values measured for the same primary alcohol series in conventional single-headed, single-tailed surfactants. Surprisingly, the partition coefficients of the alcohols in the symmetric gemini aggregates exhibited little, if any, dependence on the spacer length of the gemini amphiphiles and were remarkably consistent as the length of the main surfactant chain increased at constant spacer length. When these results are compared to the partition coefficients of the same alcohols in corresponding monomeric surfactants, we observe little difference in the thermodynamic driving forces governing the transfer of alcohols from water to the aggregates of either monomeric or symmetric gemini surfactants.

Gemini surfactants are composed of two hydrocarbon tails with corresponding polar headgroups, linked via a covalent spacer. The synthesis of these surfactants is a very active area of research due to their application as catalysts and other applied areas of study. The modification of green microwave techniques developed in our research on ionic liquids has resulted in the significant improvement of the synthesis of N,N '-bis(dimethylalkyl)-α,ω-alkanediammonium dibromide (m-s-m type) symmetrical gemini surfactants. This approach utilizes a remarkably more economical, green, and sustainable methodology for the production of symmetrical gemini surfactants that can be utilized in numerous commercial applications. The improved synthetic approach of these gemini surfactants has led to the characterization of their crystalline packing for the first time ever using X-ray crystallographic analysis., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

The effects of food availability and infection with the microsporidium Nosema adaliae on alkaloid production in the two-spotted lady beetle, Adalia bipunctata L., was examined. Alkaloid production (relative percent adaline in reflex-fluid) and pathogen load (spore counts) were quantified for both uninfected and N. adaliae-infected A. bipunctata. Alkaloid content was significantly higher for beetles fed irregularly than for those fed daily. For beetles infected with N. adaliae, spore counts were significantly higher for those fed irregularly compared to those fed daily. These results suggest that adaline content in reflex-fluid is influenced by infection and that irregular food supply increases pathogen load., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Nosema adaliae, a microsporidian pathogen described from the two-spotted lady beetle, Adalia bipunctata L., delays larval development when A. bipunctata is reared under laboratory conditions at 25 °C. In nature, lady beetles often experience a wide range of environmental temperatures, but little is known regarding the effects of microsporidian pathogens on lady beetles when they are reared at higher and lower temperatures. In this study, the effects of elevated rearing temperatures and microsporidiosis were observed on larval development time and mortality, sex ratios, alkaloid content (adaline and adalinine), and adult morphometrics. Uninfected larvae (24 h-old) were provided either an uninfected or N. adaliae-infected conspecific egg and subsequently reared at three temperatures (25 °C, 27.5 °C or 30 °C). After the egg was eaten, larvae were provided a diet of green peach aphids and their development was recorded daily. Following eclosion, a subsample of adults were photographed for microscopic measurements and reflex-fluid was collected for alkaloid analysis using gas chromatography-mass spectrometry. Afterwards, all individuals were examined to determine the number that had become infected, and the same subsample was used to assess the severity of infection. Development time was delayed significantly for larvae that consumed a N. adaliae-infected egg, and infected larvae took significantly longer to develop at 25 °C than at 27.5 °C or 30 °C. No differences were observed for larval mortality or sex ratios. The relative proportion of adaline increased when larvae were reared at 30 °C, but adaline concentration was not affected by the pathogen, N. adaliae. Adults reared at 25 °C had larger body measurements when compared to those reared at 27.5 °C and 30 °C. Overall, adults that had eaten a N. adaliae-infected A. bipunctata egg as larvae had similar body measurements to those that ate an uninfected egg. When comparing male and female measurements, a significant interaction between infection status, temperature and sex was observed for elytra length and head capsule width only. These measurements were similar for uninfected and N. adaliae-infected females across all temperatures. However, when reared at 25 °C, uninfected males had significantly smaller elytra and head capsules than did infected males; but when reared at 30 °C, no significant difference was observed for these measurements. Both percent infection and average spore count decreased at 27.5 °C and 30 °C. These results suggest that temperatures above 25 °C have a mitigating effect against N. adaliae in A. bipunctata., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Electrochemical SERS (E-SERS) was used for the first time to study the interfacial behavior of a class of pyridinium-based biodegradable ionic liquids at a silver nanoparticle (AgNP) electrode surface. An isomeric series of ionic liquids (IL) based on 3-butoxycarbonyl-1-methylpyridinium bis(trifluoromethanesulfonyl)imide were prepared, which have demonstrable biodegradability. It was found that all four of the isomeric ionic liquids studied exhibited excellent electrochemical stability as binary mixtures combined with methanol, with the absence of any specific redox processes occurring over nearly 3.0 V of applied potential. Normal Raman measurements of the neat isobutyl IL showed a signal rich in vibrational features, with strong contributions from both the anion and the bulky organic cation. E-SERS of the neat isobutyl IL was shown to exhibit excellent potential stability, with no potential-induced orientational change at the metal surface. When the ionic liquids were prepared as methanolic binary mixtures, dissociation of the IL ions was observed, and only the organic cation was shown to adsorb at the Ag/solution interface. The nature of the substituent on the ester group of the IL series was observed to have a significant effect on the orientation of the cation on the metal surface, based on the application of the metal surface selection rules combined with computational data. Notably, the isobutyl and sec-butyl isomers were observed to have an orientation wherein the pyridinium ring was oriented perpendicular to the surface, while the tert-butyl and n-butyl isomers were observed to have an orientation wherein the pyridinium ring was lying flat on the metal surface.

A mild and simple two-step Fe(0)-mediated N-demethylation of a number of tertiary N-methyl alkaloids is described. The tertiary N-methylamine is first oxidized to the corresponding N-oxide, which is isolated as the hydrochloride salt. Subsequent treatment of the N-oxide hydrochloride with iron powder readily provides the N-demethylated amine. Representative substrates include a number of opiate and tropane alkaloids. Key intermediates in the synthesis of semisynthetic 14-hydroxy pharmaceutical opiates such as oxycodone and oxymorphone are also readily N-demethylated using this method.

A simple and effective method for the formation of stable multilamellar vesicles is reported as a potential application of ionic liquid materials (IL's) and as replacements for conventional surfactants used in such applications. The methodology is based on the various approaches for the formation of vesicles from oppositely charged surfactants. Photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM) have been used to estimate the size of the aggregates; the TEM studies have also revealed morphological differences in the self-assembled systems with changing ionic liquid material. Size measurements from PCS indicate consistent growth of the ionic-liquid containing vesicles with increasing concentration of added anionic surfactant. 2D NOESY NMR spectroscopy have been used to examine the manner in which IL amphiphile self-assembles with the second surfactant in solution. A comparison has been made between the aggregates formed from hexylpyridinium tetrafluoroborate ([HexPy][BF4-])/sodium dodecylsulfate (SDS) and hexylpyridinium bromide ([HexPy][Br])/sodium dodecylsulfate (SDS).

Imidazolium salts containing salicylaldoxime or salen ligands readily form ionic metal complexes with copper and manganese; hence offering applications in metal extractions and biphasic catalysis.

A new class of imidazolium salts with appended aminodiacetic acid moieties as di-tert-butyl esters has been synthesized. An improved synthetic route compared to that previously reported is described. These task specific ionic liquids have been used for the formation of metal chelates with Cu(II), Ni(II) and Co(II) in aqueous solutions. The hydrophobicity and solubility of these metal complexes has been fine-tuned by changing the properties of the imidazolium salts from which they are derived through the introduction of alkyl chains onto the imidazolium core.

An imidazolium-based task-specific ionic liquid containing an ethylaminediacetic acid moiety readily results in the formation of 2:1 octahedral chelate complexes with aqueous Co2+, Ni2+, and Cu2+.

The tributylstannyl anion, Bu3Sn-, can be generated in imidazolium based ionic liquids from Me3SiSnBu3 and reacted with alpha,beta-unsaturated carbonyl compounds to afford 3-tributylstannylated products in good yields.

We present here a reassessment of our transition-metal free Suzuki-type coupling protocol. We believe that, although the reaction can be run without the need for addition of a metal catalyst, palladium contaminants down to a level of 50 ppb found in commercially available sodium carbonate are responsible for the generation of the biaryl rather than, as previously suggested, an alternative non-palladium-mediated pathway. We present a revised methodology for Suzuki couplings using ultralow palladium concentrations for use with aryl and vinyl boronic acids and discuss the effects of the purity of the boronic acid on the reaction.

A modified Polonovski reaction has been employed to N-demethylate several opiate alkaloids in moderate to high yield. This method provides an alternative to traditional N-demethylation procedures which utilize toxic reagents such as cyanogen bromide or expensive reagents such as vinyl chloroformate. The current synthesis involves N-oxide formation, isolation of the corresponding N-oxide hydrochloride, and an FeSO(4).7H(2)O mediated Polonovski reaction to afford the desired secondary amine.

Silylstannanes can be regioselectively added across terminal alkynes in a quantitative fashion in the presence of a palladium(0) catalyst immobilised in the [bmim]PF6 ionic liquid which can be recycled without loss of activity.

Four hundred and sixteen male and 233 female subjects were observed in a university cafeteria at lunch time. They were categorized according to five perceived weight groups with category one being underweight and category five being overweight. The number of calories in the food bought for lunch by each subject was calculated and recorded. Males bought food containing more calories than females but for males the amount of calories did not differ by perceived weight category. Females purchased food with fewer calories than males but the heavier females bought food with higher caloric content.

Studies on obesity and overweight measure the actual caloric amount in the foods selected or consumed. However, the food choices of individuals partly depend, if weight is a concern, on their social perception of caloric values of various foods. The study concerned the accuracy of 53 males and 82 females of various weight categories in their perception of the caloric content of various types of food. The more females weigh the more calories they perceive in food while the more males weigh the less calories they perceive in food. Both males and females overestimate the caloric content of desserts, particularly in comparison to main dishes like meat and potatoes.

As part of a large survey of addictive behavior in high school students, 43% of a sample of 278 (26% of the males, 57% of the females) scored above the cutoff point set by Overeaters Anonymous on their scale for assessing compulsive overeating. While this at-risk group did not report poorer general adjustment, health, or school achievement than did the students not at risk, they did significantly more often perceive their life quality and relationship with the person closest to them as less positive. The at-risk subsample indicated the defensive effectiveness of overeating in their significantly more frequent report of dissociative experiences while eating, and less severe ratings of insecurity, worrying, and daydreaming. One of the most salient findings was the at-risk students' more frequent report of addictive problems in their parents (overeating, alcohol and drug use, and gambling).

The synthesis of a new series of 3-azidomethyl-3-methyl-1-aryltriazenes is described. 3-Acetoxymethyl-3-methyl-1-aryltriazenes react with a large molar excess of sodium azide in aqueous acetone to afford the 3-azidomethyltriazenes in high yield. The rate of formation of the azidomethyltriazene increasing azide concentration, suggesting either an SN2 mechanism or a significant ionic strength effect on an SN1 reaction. In the absence of azide ion, the acetoxymethyltriazene undergoes a slow hydrolysis to give a bis-anilinomethane, which presumably arises via hydrolysis of the triazene to the aniline followed by condensation with formaldehyde released during the hydrolysis. The azidomethyltriazenes undergo facile hydrolysis in aqueous buffer solution with identical kinetic parameters to those of the hydrolysis of hydroxymethyltriazenes, suggesting that the azides may be good pro-drugs for the cytotoxic monomethyltriazene, the hydrolysis product derived from the hydroxymethyltriazene. Indeed, the azidomethyltriazenes have comparable anti-tumour activity against the P388 and PC6 tumours to other triazenes in this series. Furthermore, the azidomethyltriazenes display selective toxicity towards a human tumour cell line (the BE cell line) which is deficient in the repair of O6-methylguanine lesions, suggesting that these triazenes are capable of generating the monomethyltriazene without the need for metabolic activation.

As part of a large survey of addictive behavior in high school students, a group of 43 girls and 34 boys was identified who denied any use of drugs, alcohol, or tobacco. These apparently invulnerable adolescents were compared to the rest of the "user" sample on the remaining items of the questionnaire. The invulnerable students reported generally better physical and mental health and academic achievement. They also indicated a significantly lower rate of similar problems in their parents.

Four goldfish (Carassius auratus, comet) were reinforced with food when they intercepted a beam of light. Each fish performed on both CRF and VI 50-sec schedules. In subsequent extinctions, the CRF schedule produced more responses on the first day than did VI, but after the first day the post-CRF rate dropped much more rapidly. These results agree with those previously obtained in birds and mammals.