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71.
This study determined the concentrations of organochlorine contaminants in common seafood in two Chinese coastal cities (Guangzhou and Zhoushan), and assessed the health risk due to the daily consumption of contaminated seafood. Twenty-six pooled samples, belonging to five food categories (fish, bivalves, shrimp, crab, and cephalopods), were purchased from local markets in Guangzhou and Zhoushan in 2003 and 2004. These samples were analyzed for total polychlorinated biphenyls (PCBs), non- and mono-ortho-PCBs (coplanar PCBs), polychlorinated naphthalenes (PCNs), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs). The concentrations of total PCBs and coplanar PCBs in fish samples were higher in Guangzhou than in Zhoushan, while the levels of PCNs and PCDDs/DFs were comparable between the two cities. The total daily intake values of dioxin-like compounds were 1.05 and 0.86pg WHO-TEQ/kg body weight in Guangzhou and Zhoushan, respectively. Hazard ratios of non-cancer risk in the two cities were all less than unity.  相似文献   
72.
Hydrogen(H2) production from lignocellulosic materials may be enhanced by removing lignin and increasing the porosity of the material prior to enzymatic hydrolysis. Alkaline pretreatment conditions,used to delignify disposable wooden chopsticks(DWC) waste, were investigated. The effects of NaOH concentration, temperature and retention time were examined and it was found that retention time had no effect on lignin removal or carbohydrate released in enzymatic hydrolysate. The highest percentage of lignin removal(41%) was obtained with 2% NaOH at 100℃, correlated with the highest carbohydrate released(67 mg/gpretreated DWC) in the hydrolysate. An enriched culture from a hot spring was used as inoculum for fermentative H2 production, and its optimum initial pH and temperature were determined to be 7.0 and 50℃, respectively. Furthermore, enzymatic hydrolysate from pretreated DWC was successfully demonstrated as a substrate for fermentative H2 production by the enriched culture. The maximum H2 yield and production rate were achieved at 195 mL H2/g total sugarsconsumedand 116 mL H2/(L·day), respectively.  相似文献   
73.
Male butterflies compete over mating territories via aerial interactions. It has often been suggested that flight performance, and thus flight-related traits, would play an important role in butterflies’ contest resolution; however, most studies have not demonstrated a clear relationship between these traits and territory ownership in butterflies. Males of the satyrine butterfly Lethe diana compete over territories via linear chases, a behavior that is uncommon among butterflies: rather, contests of most butterfly species consist of circling flights. In the present study, some morphological and physiological traits of L. diana were compared between territory owners and intruders to search for traits correlated with resource holding power (RHP). Territory owners had higher flight-muscle ratio (FMR) and were heavier than intruders, indicating that flight performance plays a key role in their contest resolution. Contest duration was not affected by the owners’ FMR or body mass, and thus I obtained no evidence supporting the hypothesis that contestants assess their relative RHP before making a decision to retreat. I speculate that the fact that these traits had an effect on territorial status in L. diana was a result of the characteristics of the contest behavior of this butterfly. During their contests, males L. diana fly faster in their linear flights than males of most other butterflies, which engage in slower circling flights. Therefore, males of L. diana probably need higher flight performance capabilities in order to win their contests.  相似文献   
74.
This systematic review and meta-analysis aimed to review the optimal timing of delivery at term for neonates with prenatally diagnosed congenital diaphragmatic hernia (CDH). We reviewed the literature up to December 19, 2022 using MEDLINE and the Cochrane Library databases. The inclusion criteria were original articles, comparative studies of CDH neonates delivered at an early term (37–38 weeks of gestation) and at full term (39 weeks of gestation or later), and comparative studies investigating outcomes of CDH neonates. Six studies met the inclusion criteria, including 985 neonates delivered at an early term and 629 delivered at full term. The cumulative rate of survival to discharge showed no significant difference between CDH neonates delivered at an early term (395/515; 76.7%) or at full term (345/467; 73.9%) (risk ratio [RR] 1.01; 95% confidence interval [CI], 0.89–1.16; p = 0.85). Furthermore, the number of neonates requiring oxygen therapy at discharge was not significantly different between CDH neonates delivered at an early term (32/370; 8.6%) and at full term (14/154; 9.1%) (RR, 0.99; 95% CI, 0.36–2.70; p = 0.99). Therefore, the optimal timing of delivery at term for neonates with CDH remains unclear.  相似文献   
75.
76.
Polychlorinated biphenyls (PCBs), organochlorine pesticides and organotin compounds were determined in the blubber and liver of Caspian seals (Phoca caspica) found stranded on the coast of the Caspian Sea during an outbreak of canine distemper virus (CDV) in 2000. Among organochlorines analyzed, DDTs were the most dominant contaminants with concentrations ranging from 6.3 to 470 microg/g on a lipid-weight basis. Caspian seals collected in 2000 during the epizootic had higher concentrations of organochlorines than healthy individuals sampled in 1998. However, the blubber layer was generally thinner in the seals collected in 2000 than those in the previous surveys. Although compositions of organochlorine pesticides in seals suggested that the contamination status in the Caspian Sea is improving, the levels found in Caspian seals in 2000 were comparable to those in other marine mammals that have suffered from epizootics. This implies that the present status of contamination found in Caspian seals poses a risk of immunosuppression. Concentrations of butyltin compounds in livers of seals ranged from 0.49 to 17 ng/g on a wet-weight basis and octyltin compounds were below limit of detection in all the samples analyzed, suggesting less contamination by organotin compounds in the Caspian Sea.  相似文献   
77.
Several ISO standards for determining the ultimate aerobic/anaerobic biodegradability of plastic materials have been published. In particular, ISO 14855-1 is a common test method that measures evolved carbon dioxide using such methods as continuous infrared analysis, gas chromatography or titration and others (ISO 14855-1(2005.9)). This method is a small-scale test for determining the ultimate aerobic biodegradability of plastic materials, where the amounts of compost inoculum and test sample in one tenth comparing with that of ISO 14855-1. This method is well versed in ISO/DIS 14855-2 which the carbon dioxide evolved from test vessel is determined by gravimetric analysis of carbon dioxide absorbent. The focus of this study is to elucidate statistically the results of round robin test by seven countries used MODA, which were various deviations among the experiments.  相似文献   
78.
Thelytokous parthenogenesis in which diploid females are produced from unfertilized eggs, was recently reported for some ant species. Here, we document thelytokous reproduction by queens in the polygynous species Pyramica membranifera. Queens that emerged in the laboratory were kept with or without workers under laboratory conditions. Independent colony founding was successful for a few queens if prey was provided. All artificial colonies, which started with a newly emerged queen and workers produced new workers and some of the colonies also produced female sexuals. Some of the female sexuals shed their wings in the laboratory and started formation of new polygynous colonies. Workers had no ovaries and thus, were obligatorily sterile.  相似文献   
79.
An estrogen receptor (ER)/androgen receptor (AR) ligand competitive binding assay (ER/AR-binding assay) and chemical analyses were used to evaluate the endocrine disrupting chemicals (EDCs) behavior of two municipal wastewater treatment plants (WWTPs) (K and S). In the influents, estrone (E1), androsterone (A), androstenedione (AD), BPA (bisphenol A), NP (nonylphenol) and daidzein (DZ) were detected in high amounts with subsequent 24 h-average concentrations of 350, 1000, 29, 1300, 3900, and 5700 ng/L in K-WWTP and of 310, 620, 59, 1600, 2600, and 8400 ng/L in S-WWTP. The estrogenic (androgenic) activity as 17 -estradiol (E2) equivalents (EEQ) or testosterone (Te) equivalents (TEQ) was consequently 620 ng E2/L (570 ng Te/L) and 580 ng E2/L (800 ng Te/L) for the two WWTPs. The removal e ciencies of the above mentioned sole target chemicals were 51%–100% for K-WWTP and 55.6%–100% for S-WWTP. The removal e ciencies of EEQ were about 73% for both WWTPs, while the removal e ciencies of TEQ were 62.1% for K-WWTP and 98.4% for S-WWTP. In addition, chemical-derived EEQ were about 1.2%–52.4% of those by ER-binding assay for K-WWTP and the corresponding ratios were 1.3%–83.3% for S-WWTP, while chemical derived TEQ were less than 3% of values measured by the AR-binding assay for both WWTPs.  相似文献   
80.
Many butterflies acquire nutrients from non-nectar sources such as puddles. To better understand how male Papilio butterflies identify suitable sites for puddling, we used behavioral and electrophysiological methods to examine the responses of Japanese Papilio butterflies to Na+, K+, Ca2+, and Mg2+. Based on behavioral analyses, these butterflies preferred a 10-mM Na+ solution to K+, Ca2+, and Mg2+ solutions of the same concentration and among a tested range of 1?mM to 1?M NaCl. We also measured the ion concentrations of solutions sampled from puddling sites in the field. Na+ concentrations of the samples were up to 6?mM, slightly lower than that preferred by butterflies in the behavioral experiments. Butterflies that sipped the 10?mM Na+ solution from the experimental trays did not continue to puddle on the ground. Additionally, butterflies puddled at sites where the concentrations of K+, Ca2+, and/or Mg2+ were higher than that of Na+. This suggests that K+, Ca2+, and Mg2+ do not interfere with the detection of Na+ by the Papilio butterfly. Using an electrophysiological method, tip recordings, receptor neurons in contact chemosensilla inside the proboscis evoked regularly firing impulses to 1, 10, and 100?mM NaCl solutions but not to CaCl2 or MgCl2. The dose?Cresponse patterns to the NaCl solutions were different among the neurons, which were classified into three types. These results showed that Japanese Papilio butterflies puddle using Na+ detected by the contact chemosensilla in the proboscis, which measure its concentration.  相似文献   
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