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11.
Regular sea urchins, which have pentaradial symmetry, have been believed to show no preference in which part of the body forward
they proceed with. Through use of circular statistics, we show that the regular sea urchin Hemicentrotus pulcherrimus had no preference with respect to what body part, as determined by Lovén’s system, should be anterior in locomotion. The
sea urchins, however, preferably proceeded with the body part, which had contacted with the aquarium walls at rest, forward.
When the contact part was artificially altered, the body part facing forward in the following proceeding changed accordingly:
the animals walked with the part that had contacted last forward. The biological significance of this behavior was discussed
in relation to the aggregation formation and homing behavior. 相似文献
12.
Vagile animals usually have bilaterally symmetrical bodies and proceed with their mouth-end first. Regular sea urchins have,
however, radially symmetrical bodies with their mouth facing the substratum and show no preference in which side of the body
should be anterior in their locomotion. The elliptical sea urchins in the subfamily Echinometrinae are exceptional among regular
sea urchins in having elongated bilateral bodies. We studied whether they showed the preference in the direction of locomotion
using Echinometra sp. type A. Directional preference was not observed in the proceedings in an open space. However, they proceeded preferentially
with their long axis coinciding with the direction of locomotion when they moved along the water surface or along the wall
of the aquarium. The speed of locomotion was the same irrespective of the direction of proceedings and of whether sea urchins
moved freely or moved along the water surface or along the walls. We suggest that the bilateral body form and the habit of
long-axis lead of this sea urchin have adaptive significance to increase the protected body surfaces, not to facilitate the
efficiency in locomotion. 相似文献
13.
Xue Q Shimizu K Sakharkar MK Utsumi M Cao G Li M Zhang Z Sugiura N 《Environmental science and pollution research international》2012,19(3):700-707
Introduction
Initial geosmin degradation was closely related to water temperature and natural geosmin concentration of sampling environment. Here, for the first time, we evaluated the biodegradation of geosmin by microorganisms in biofilm from biological treatment unit of actual potable water treatment plant. 相似文献14.
15.
Poly(pheniothiazine) films were prepared on a porous carbon felt (CF) electrode surface by an electrooxidative polymerization of
three phenothiazine derivatives (i.e.,Tthionine (TN), Toluidine Blue (TB) and Methylene Blue (MB)) from 0.1 mol/L phosphate buffer
solution (pH 7.0). Among the three phenothiazies, the poly(TB) film-modified CF exhibited an excellent electrocatalytic activity for
the oxidation of nicotinamide adenine dinucleotide reduced form (NADH) at +0.2 V vs. Ag/AgCl. The poly(TB) film-modified CF
was successfully used as working electrode unit of highly sensitive amperometric flow-through detector for NADH. The peak currents
(peak heights) were almost unchanged, irrespective of a carrier flow rate ranging from 2.0 to 4.1 mL/min, resulting in the measurement
of NADH (ca. 30 samples/hr) at 4.1 mL/min. The peak current responses of NADH showed linear relationship over the concentration
range from 1 to 30 mol/L (sensitivity: 0.318 A/( mol/L); correlation coefficient: 0.997). The lower detection limit was found to be
0.3 mol/L (S/N = 3). 相似文献
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Kazuya Mimura Masayuki Endo Yoko Kawanishi Takeshi Kanagawa Kouji Nagata Keita Terui Makoto Fujii Masayuki Shiraishi Masaya Yamoto Miharu Ito Atsuo Itakura Hiroomi Okuyama Noriaki Usui the Japanese Congenital Diaphragmatic Hernia Study Group 《黑龙江环境通报》2023,43(8):993-1001
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
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Jun-ichi Kadokawa Kanako Hirohama Shozaburo Mine Takeshi Kato Kazuya Yamamoto 《Journal of Polymers and the Environment》2012,20(1):37-42
In this study, we performed the facile preparation of chitin/cellulose composite films using two ionic liquids, 1-allyl-3-methylimidazolium
bromide (AMIMBr) and 1-butyl-3-methylimidazolium chloride (BMIMCl); the former dissolves chitin and the latter dissolves cellulose.
First, solutions of chitin in AMIMBr and cellulose in BMIMCl were individually prepared by heating each mixture at 100 °C
for 24 h. Then, the homogeneous mixture of the two solutions was thinly casted on a glass plate, followed by standing at room
temperature for 2 h. After the material was subjected to successive Soxhlet extractions with ethanol for 12 h and with water
for 12 h, the residue was dried at room temperature to give a composite film. The crystalline structures of the polysaccharides
were evaluated by the X-ray diffraction measurement. Furthermore, the thermal stability and mechanical property of the resulting
composite film were estimated by the thermal gravimetric analysis measurement and tensile testing, respectively. 相似文献
20.
Shinso Yokota Kazuya Iizuka Futoshi Ishiguri Zensaku Abe Nobuo Yoshizawa 《Journal of Material Cycles and Waste Management》2006,8(2):140-144
Delignification from the cell walls with a combination of ozone oxidation and dioxane–water extraction using thin sections
of a softwood, Japanese cypress (Chamaecyparis obtusa Endl.), was studied to determine its suitability for the production of recyclable cellulose-based materials from wood waste.
The visible-light absorption spectra of treated wood sections revealed that delignification from the cell walls with ozone
increased with increasing ozonization time. Ozone delignification proceeded from the lumen side toward the middle lamella
within the secondary wall of a cell, and it proceeded faster in early wood than in late wood within an annual ring. Mild ozonization
for 10–30 min was sufficient for the removal of lignin from the cell walls when sections were extracted with dioxane after
ozonization. The results obtained here demonstrate that microspectrometry coupled with the Wiesner reaction is useful for
the quantitative analysis of lignin in cell walls. 相似文献