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Viviparous rockfishes (Sebastes spp., family Scorpaenidae) mate and store sperm in the ovaries for several months prior to fertilization, as oocytes develop for the parturition season. Although multiple paternity has been documented in single‐brooding rockfishes, paternity in consecutive broods of multiple‐brooding species has not been studied. Analyses of multilocus microsatellite genotypes in both residual larvae left in the ovary from a previous parturition and upcoming fertilized broods in the same ovary demonstrated evidence of the same sires in consecutive broods in chilipepper (Sebastes goodei) and speckled (Sebastes ovalis) rockfishes. One S. goodei mother showed evidence of multiple paternity from the same two sires in both consecutive broods. The ability to retain sperm, even after a parturition event, for use in subsequent broods, confers an advantage to ensure fertilization and allows for extension of the parturition season. This life‐history strategy provides a bet‐hedging advantage in the California Current system, an environmentally dynamic ecosystem where larval survivorship and subsequent recruitment to adult populations can vary temporally by orders of magnitude. [ABSTRACT FROM AUTHOR]

BACKGROUND: Crop protection solutions for the control of key economic sucking pests derive essentially from neuronal and muscular acting chemistries, wherein neonicotinoid uses largely dominated for the last two decades. Anticipating likely resistance development of some of those arthropod species to this particular class, we intensified research activities on a non‐neuronal site of action targeting insect growth and development some 10 years ago. RESULTS: Our innovation path featured reactivation of a scarcely used and simple building block from the 1960s, namely N‐methoxy‐4‐piperidone 3. Its judicious incorporation into the 2‐aryl‐1,3‐dione scaffold of IRAC group 23 inhibitors of fatty acid biosynthesis resulted in novel tetramic acid derivatives acting on acetyl‐coenzyme A carboxylase (ACCase). The optimization campaign focused on modulation of the aryl substitution pattern and understanding substituent options at the lactam nitrogen position of those spiroheterocyclic pyrrolidine‐dione derivatives towards an effective control of sucking insects and mites. This work gratifyingly culminated in the discovery of spiro N‐methoxy piperidine containing proinsecticide spiropidion 1. Following in planta release, its insecticidally active dione metabolite 2 is translaminar and two‐way systemic (both xylem and phloem mobile) for a full plant protection against arthropod pests. CONCLUSION: Owing to such unique plant systemic properties, growing shoots and roots actually not directly exposed to spiropidion‐based chemistry after foliar application nevertheless benefit from its long‐lasting efficacy. Spiropidion is for use in field crops, speciality crops and vegetables controlling a broad range of sucking pests. In light of other performance and safety profiles of spiropidion, an IPM fit may be expected. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Forecasts from climate models and oceanographic observations indicate increasing deoxygenation in the global oceans and an elevated frequency and intensity of hypoxic events in the coastal zone, which have the potential to affect marine biodiversity and fisheries. Exposure to low dissolved oxygen (DO) conditions may have deleterious effects on early life stages in fishes. This study aims to identify thresholds to hypoxia while testing behavioral and physiological responses of two congeneric species of kelp forest fish to four DO levels, ranging from normoxic to hypoxic (8.7, 6.0, 4.1, and 2.2 mg O2/L). Behavioral tests identified changes in exploratory behavior and turning bias (lateralization), whereas physiological tests focused on determining changes in hypoxia tolerance (pCrit), ventilation rates, and metabolic rates, with impacts on the resulting capacity for aerobic activity. Our findings indicated that copper rockfish (Sebastes caurinus) and blue rockfish (Sebastes mystinus) express sensitivity to hypoxia; however, the strength of the response differed between species. Copper rockfish exhibited reduced absolute lateralization and increased escape time at the lowest DO levels, whereas behavioral metrics for blue rockfish did not vary with oxygen level. Both species exhibited decreases in aerobic scope (as a function of reduced maximum metabolic rate) and increases in ventilation rates to compensate for decreasing oxygen levels. Blue rockfish had a lower pCrit and stronger acclimation response compared to copper rockfish. The differences expressed by each species suggest that acclimatization to changing ocean conditions may vary, even among related species that recruit to the same kelp forest habitat, leading to winners and losers under future ocean conditions. Exposure to hypoxia can decrease individual physiological fitness through metabolic and aerobic depression and changes to anti‐predator behavior, with implications for the outcome of ecological interactions and the management of fish stocks in the face of climate change. [ABSTRACT FROM AUTHOR]

Sustainable and conventional farming systems use fertilizers that differ in the availability of nitrogen, which may affect plant quality to alter the abundance and performance of potential pest species., We grew brassica plants in several types of fertilizer, including those commonly used in conventional and sustainable farming systems, and an unfertilized control. The effects of fertilizer type on the performance of two aphid species and foliar glucosinolate content were investigated., Both aphid species performed poorly (with reduced fecundity) on the unfertilized treatment compared with those feeding on fertilized host plants., Brevicoryne brassicae, the brassica specialist, performed best on Brassica oleracea plants fertilized with an organic animal manure, with a 72% increase in fecundity and an 18% increase in intrinsic rate of increase compared with plants fertilized with ammonium nitrate., By contrast, the generalist Myzus persicae had an intrinsic rate of increase that was reduced by 15% on plants growing in the animal manure compared with those growing in ammonium nitrate., These results may explain earlier findings on the effects of fertilizer type on aphid populations in the field, and are discussed in the context of pest species' responses to sustainable and conventional agricultural systems. [ABSTRACT FROM AUTHOR]

The effects of two anorectic drugs, dexfenfluramine and phentermine, on food intake under different food-access conditions were examined. Experiment 1 compared the effects of these drugs on food intake under a progressive-ratio (PR) schedule and free-access conditions. Dexfenfluramine decreased food intake under both conditions, but the doses required to decrease intake under free-access conditions were higher than those required to reduce intake trader the PR condition. Inter mediate doses of phentermine sometimes increased breaking points, and higher doses decreased them. Phentermine decreased food intake at the same doses under both access conditions. Thus the potency of dexfenfluramine, but not phentermine, to decrease food-maintained behavior depended upon the food access condition. Experiment 2 used a novel mixed progressive-ratio schedule of food delivery to study the duration of drug effects. Sessions consisted of five components separated by 3-hr timeouts. The ratio requirement reset at the beginning of each component and a new breaking point was obtained. Both dexfenfluramine and phentermine dose-dependently decreased breaking points early in the session. In some rats, compensatory increases in breaking point were observed. That is, breaking points later in the session increased over control levels, resulting in no change in the total number of food pellets earned for the session compared to control. The present findings suggest that the effects of some anorectic drugs depend upon the access conditions for food; increasing the effort to obtain food may enhance their ability to decrease food-maintained behavior. [ABSTRACT FROM AUTHOR]

Presents a study which examined the effects of step size and break-point criterion on the progressive-ratio performance of pigeons. How key pecking by pigeons was maintained; Information on progressive-ratio schedules of food delivery in pigeons; Details on the experiments conducted on the pigeons; Factors which influence pigeons pecking behavior; Results of this study.

This article examines the theory and practice of rent control in the UK and elsewhere in order to contribute to the important debate on the future of the private rental sector UK. Our opposition to rent and eviction controls is unequivocal. We shall show that wherever control has been imposed the effects have been, at best, adverse and at worst, appalling. The effects on the quantity and quality of a housing stock can be so devastating that one Swedish socialist economist, Assar Lindbeck (1967) concluded: "In many cases rent control to be the most efficient technique presently known to destroy a city--except for bombing." Controls which lead to an excess demand for housing foster unfortunate practices discrimination on various grounds other than willingness and ability to pay rent, and the creation of a black market. Rent and eviction controls also have a major impact mobility of labour. The encouragement to immobility can lead to the perpetuation structural imbalances in an economy prompting rigidities which can have considerable economic and social costs. [ABSTRACT FROM AUTHOR]

Comments on a legislative bill that would deregulate the rental housing market in Great Britain. Key provisions; Households affected by the legislation; Other efforts of the government to liberalize the housing sector; Pitfalls of the proposal.

Offers advice to the British government on how to speed up sale of council houses in Great Britain. Irreversible transfer of council housing to private ownership; Promotion of voluntary purchases by improving attractiveness of terms; Extended housing rebate scheme for poorer tenants.

The effect of a saline cathartic combined with activated charcoal or activated charcoal alone on aspirin bioavailability was characterized in six healthy volunteers. Using a random, Latin-square design, subjects were given 975 mg aspirin followed by either water alone, 15 Gm activated charcoal (AC), or 15 Gm activated charcoal plus 20 Gm sodium sulfate (AC + SS) separated by one week. Both AC (44.16 ± 16.85 μg/ml) and AC + SS (58.61 ± 10.63 μg/ml) decreased ( P < 0.001) the maximal plasma salicylate concentration ( Cpmax) compared to control (86.61 ± 12.69 μg/ml). Urinary salicylate recovery was decreased ( P < 0.01) for AC (57.88 ± 16.26 per cent) and AC + SS (61.00 ± 11.49 per cent) as compared to control (93.73 ± 6.83 per cent), while for area under the plasma concentration-time curve ( AUC) only AC showed a decrease ( P < 0.01) compared to control. Neither AC nor AC + SS differed from each other for Cpmax, AUC, or cumulative urinary recovery. Our findings indicate that the addition of sodium sulfate to activated charcoal has no added effect on limiting aspirin absorption relative to activated charcoal alone. [ABSTRACT FROM AUTHOR]