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The fate of pharmaceuticals after discharged from hospital into wastewater was clarified experimentally by using a new lab-scale conventional activated sludge (CAS) treatment reactor. The 43 target compounds belong to nine therapeutic classes (antivirals, antibacterials, anticancer drugs, psychotropics, antihypertensives, analgesic–antipyretics, contrast media, herbal medicines, and phytoestrogens) were selected with inclusion of 16 newly estimated compounds. The efficiency of the present reactor was estimated by comparing the reaction rate constant of the solid-water partition coefficients (log Kd) between liquid and solid samples and half-life during 48-h experiment obtained by using hospital effluents with those obtained by using STP wastewater. The results that no significant difference in removal efficiency was observed between both water samples (P?>?0.05) indicate high reliability of the present lab-scale reactor. The actual rates of removal when hospital effluent was applied varied widely (mean, 59?±?40%) independent of type of the pharmaceuticals. More than 90% of 17 compounds were removed after 8 h of treatment. However, the values for psychotropics (mean, 19?±?26%) and contrast media (mean, 24?±?17%) were generally low, indicating high stability. The log Kd values ranged from 1.3 to 4.8. Notably, clarithromycin, acridine, and glycitein could be removed in both liquid and solid phases. The dominant removal mechanisms were found to be different for individual pharmaceutical. These results suggest the effectiveness of introduction of the lab-scale biological treatment system for development of a new solution for discharge of pharmaceuticals from hospital.

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The purpose of this study was to compare the effects of 2 kinds of underwear made from hydrophobic and hydrophilic fabrics on the mean skin temperatures and clothing microclimate (temperature, humidity) in participants performing intermittent exercise in cold environmental conditions.

One or 2 layers of cotton underwear (C1, C2) with a 2-piece long-sleeved shirt and long-legged trousers, and 1 or 2 layers of polypropylene underwear (P1, P2) with a 2-piece long-sleeved shirt and long-legged trousers were used as experimental underwear. In addition, the participants wore a 2-piece ski suit as 100% polyester clothing including 100% polyester padding. Ten young adult females volunteered as participants. The experiments were performed in a climatic chamber at an ambient temperature (Ta) of 0°C and an air velocity of 0.26 m s?1.

The major findings are summarized as follows: (a) Although the clothing microclimate humidity was not different within the ski suit of outer clothing between C1 and P1, it was significantly higher in P2 than in C2; (b) Clothing microclimate temperature inside the ski suit did not differ between C1 and P1, whereas it was significantly higher in P2 than in C2; (c) The thermal gradient between innermost and outermost of clothing microclimate at back level did not show any difference between C1 and P1, but it was significantly higher in C2 than in P2. These results are discussed in terms of thermal physiology and clothing sciences.  相似文献   
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Male genitalia show rapid and divergent evolution. It is rarely determined whether variation in male genital morphology influences male reproductive success. Male damselflies possess a unique aedeagus with a re-curved head and spiny lateral processes, and most females have two sperm storage organs, a spherical bursa copulatrix and a tubular spermatheca. Previous studies have indicated that the re-curved head may remove bursal sperm, whereas the lateral processes remove spermathecal sperm. However, we need more direct evidence of these functions. We compared sperm number in female sperm storage organs by interrupting copulation to examine sperm removal by the male. In Calopteryx cornelia, males removed almost all bursal sperm but only partially removed spermathecal sperm. In contrast, females of Mnais pruinosa store sperm primarily in the bursa, and males removed only bursal sperm. To examine the functions of male spiny lateral processes, we compared mating behaviour between control and experimental males from which we removed (cut) the lateral processes. In C. cornelia, cutting of the lateral processes resulted in a decreased number of abdominal movements during copulation and no removal of spermathecal sperm. The amount of bursal sperm removed during copulation also decreased in experimental males compared to the unmanipulated males. However, in M. pruinosa, the experimental removal of male lateral processes did not decrease the abdominal movements and little affected the removal of bursal sperm. Inter-specific differences between C. cornelia and M. pruinosa may be caused by variation in the strategies of female sperm storage.  相似文献   
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Kemmochi Y  Tsutsumi K  Futami K 《Chemosphere》2002,46(9-10):1451-1455
Commercial ion trap mass spectrometer provides easy-to-operate MS/MS analysis for the determination of PCDD/PCDF. The limit of quantification is appropriately low (0.2 pg for 23478-P5CDF) because all the stages are performed in the trap and sample losses associated with the ion transportation are minimized. However, if excessive ions are injected into the trap, its electrical fields are distorted and an overall reduction in performance arises. Ionization condition is an important parameter as it affects the amount of the total ions produced. If the amount of interfering compounds are negligible, such as standard solution or cleaned-up sample, lower ionization condition (e.g. electron energy: 30 eV, emission current (EC): 150 μA) is preferable. On the contrary, in case excessive interfering ions are coexisting with PCDD/PCDF, such as crude extract or semi-cleaned-up sample, the ionization condition should be high (e.g. electron energy: 90 eV, EC: 350 μA) for the reproductive quantification.  相似文献   
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To examine the potential trophic competition between myctophids and small epipelagic fishes in the nursery grounds in spring, we compared the stomach contents of dominant myctophids (Symbolophorus californiensis, Ceratoscopelus warmingii and Myctophum asperum; = 179) and juvenile epipelagic fishes (Japanese sardine, Sardinops melanostictus, Japanese anchovy, Engraulis japonicus, chub mackerel, Scomber japonicus, and spotted mackerel, S. australasicus; = 78) that were simultaneously collected at nighttime with a midwater trawl net around the Kuroshio-Oyashio transition zone in the western North Pacific. It was clear that the neritic copepod Paracalanus parvus s.l. was the most abundant species in NORPAC samples (0.335 mm mesh size) taken at the same stations. Diets of dominant myctophid fishes differed from those of the juvenile epipelagic fishes; Japanese sardine and anchovy mostly preyed upon P. parvus s.l. (23.6% of stomach contents in volume) and Corycaeus affinis (16.1%), respectively. Both chub and spotted mackerels mainly preyed upon the seasonal vertical migrant copepod, Neocalanus cristatus (15.9 and 14.7%, respectively). On the contrary, myctophid fishes probably do not specifically select the abundant neritic copepods. Namely, S. californiensis mostly preyed upon a diel vertical migrating copepod, Pleuromamma piseki (22.7 and 30.6% in stomach of juvenile and adult, respectively), while C. warmingii and M. asperum preyed on Doliolida (43.0% in stomach of juvenile C. warmingii), appendicularians (11.0% in stomach of juvenile M. asperum), and Ostracoda (6.3% in stomach of adult C. warmingii). Feeding habits of myctophid fishes seem adapted to their prey animals; low rate of digested material (less than 30% in volume) in stomachs of S. californiensis may be linked to the movement of P. piseki, hence S. californiensis can easily consume this copepod at night since they are more concentrated at night than daytime. High rate of digested material (over 40%) of M. asperum and adult C. warmingii suggest that they feed not only at night but also during the daytime in the midwater layer. Thus, myctophid fishes actually fed in the surface layer but less actively than the small epipelagic fishes. These results suggest that the potential for direct food competition between myctophids and small epipelagic fishes is low in the nursery ground, but there remains a possibility of indirect effects through their prey items, since the above gelatinous animals feed on common prey items as juveniles of Japanese sardine and anchovy.  相似文献   
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The poly(-caprolactone) (PCL) and poly[(R)-3-hydroxybutyrate] (R-PHB) films with a hydrophilic surface were prepared by the alkali treatment of their as-cast films in NaOH solutions of different concentrations. The alkali-treated PCL and R-PHB films, as well as the as-cast PCL and R-PHB films, were biodegraded in soil controlled at 25°C and the effects of alkali treatment or surface hydrophilicities on their biodegradation were investigated by the use of gravimetry, gel permeation chromatography (GPC), scanning electron microscopy (SEM), and polarization optical microscopy. It became evident that the alkali treatment enhanced the hydrophilicities and biodegradabilities of the PCL and R-PHB films in soil. The biodegradabilities of the as-cast aliphatic polyester films in controlled soil decreased in the following order: PCL > R-PHB > PLLA, in agreement with that in controlled static seawater.  相似文献   
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Airborne communication between individuals, called "eavesdropping" in this paper, can cause plants to become more resistant to herbivores when a neighbor has been experimentally clipped. The ecological relevance of this result has been in question, since individuals may be too far apart for this interaction to affect many plants in natural populations. We investigated induced resistance to herbivory in sagebrush, Artemisia tridentata, caused by experimental clipping of the focal plant and its neighbors. We found no evidence for systemic induced resistance when one branch was clipped and another branch on the same plant was assayed for naturally occurring damage. In this experiment, air contact and plant age were not controlled. Previous work indicated that sagebrush received less damage when a neighboring upwind plant within 15 cm had been experimentally clipped. Here we found that pairs of sagebrush plants that were up to 60 cm apart were influenced by experimental clipping of a neighbor. Furthermore, we observed that most individuals had conspecific neighbors that were much closer than 60 cm. Air contact was essential for communication; treatments that reduced airflow between neighboring individuals, either because of wind direction or bagging, prevented induced resistance. Airflow was also necessary for systemic induced resistance among branches within an individual. Reports from the literature indicated that sagebrush is highly sectorial, as are many desert shrubs. Branches within a sagebrush plant do not freely exchange material via vascular connections and apparently cannot rely on an internal signaling pathway for coordinating induction of resistance to herbivores. Instead, they may use external, volatile cues. This hypothesis provides a proximal explanation for why sagebrush does not demonstrate systemic induced resistance without directed airflow, and why airborne communication between branches induces resistance.  相似文献   
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