Changes in estrogen receptor expression in the chick thymus during late embryonic development     

Masafumi Katayama  Tomokazu Fukuda  Toshimitsu Hatabu  Kiyoaki Narabara  Asaki Abe  Yasuhiro Kondo 《Animal Science Journal》2014,85(3):277-285

In chickens, although estrogen receptors (ER) are reported to be associated with the immunological processes, detailed information about the differences in ER expression in the tissues related to the development of lymphocytes is not fully known, especially during the developmental stage. To learn more about this immunological relationship, we used semi‐quantitative polymerase chain reaction method to detect the ER expression levels in the thymus tissues of chicks during the developmental stage. Furthermore, ER‐expressing cells were detected by immunohistochemistry. The results of this study show that the expression level of ER increased on embryonic day 16 and decreased on day 20. Furthermore, ER expression was significantly higher in male than in female chickens at day 16. The increased expression on day 16 and decreased level on day 20 were also reproduced in the incidence of immunoreactive cells, although there was a 1‐day delay in the elevated incidence of the cells. This study revealed the changes in ER expression and the incidence of ER‐positive cells in the thymus of chickens during the developmental stage.  相似文献   

Sex reversal and nursery growth of Nile tilapia, Oreochromis niloticus (L.), free-swimming in earthen ponds     

R P Phelps  G Conterras Salazar  V Abe  B J Argue 《Aquaculture Research》1995,26(4):293-295

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Evaluating the impact of COVID-19 on ex-vessel prices using time-series analysis     

Abe  Keita  Ishimura  Gakushi  Baba  Shinya  Yasui  Shota  Nakamura  Kosuke 《Fisheries Science》2022,88(1):191-202

The spread of coronavirus disease 2019 (COVID-19) and subsequent lockdown measures have impacted economies and industries worldwide. The fisheries industry witnessed a sharp decline in demand and a slump in fish prices due to its dependence on the food service industry. It is important to quantitatively assess those fish species affected most and the extent of the pandemic’s impact on them, to take specific countermeasures. We propose a time-series analysis as an alternative to the current practice of using ad hoc year-on-year comparisons. Although the pandemic makes it difficult to construct a counterfactual approach due to the lack of an appropriate control group, we use time-series forecasting to simulate normal conditions using pre-pandemic data. In Tokyo, the unit price of fish species that were negatively impacted by the food services industry dropped by 12.65% to 14.64%, and by 26.08% to 28.22% after the declaration of a state of emergency. Seasonality, short weekly cycles, and short-term market trends are factors that affect the price of fish. Species-specific impact estimates related to the COVID-19 pandemic can allow policymakers to implement recovery measures in a more targeted and effective manner. The results of our analysis can increase fishers’ and policymakers’ awareness of the usefulness of economic analyses and incentivize them to release data to establish a system to accumulate and analyze data strategically for urgent and appropriate interventions in the fisheries industry.

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Possible influence of termites (Macrotermes bellicosus) on forms and composition of free sesquioxides in tropical soils     

Susumu S. Abe  Toshiyuki Wakatsuki 《Pedobiologia》2010,53(5):301-306

There has been less concern about soil mineralogical alteration than about soil physical, chemical and biological changes induced by termite nest-building activity. Furthermore, much less attention has been paid to free sesquioxides than to phyllosilicate minerals. In the present study, we conducted field morphological observations and selective dissolution analysis to characterize free sesquioxides in termite (Macrotermes bellicosus) mounds as compared with surrounding pedons in different toposequence positions, i.e., seasonally flooded valley bottom, hydromorphic fringe and well-drained upland sites. Distinctive redoximorphic features, such as surface yellowish layers on mound structures from the fringe site, indicate possible alteration of iron sesquioxide forms in the mounds due to the transportation of soil from reductive (aquic subsoil) to oxidative (epigeal mound) environments by the nest-building activity of M. bellicosus. On the other hand, the iron-soluble content in the dithionite-citrate-bicarbonate (DCB) system (Fe_d) was generally higher in the mound structures than at the adjacent sub-surface (Ap2) horizon at each toposequence position, while there was less difference in the content of acid ammonium oxalate (AAO) extractable iron (Fe_o) as compared to Fe_d. As a consequence, the iron activity index (Fe_d/Fe_o ratio) was found for the most part to be lower in the mound structures than in the neighboring Ap2 horizon. In addition, the content of Fe_d, AAO-soluble Al (Al_o) and DCB-extractable Al (Al_d) was significantly correlated with clay content in these soils. These findings suggest that M. bellicosus preferentially collects clay particles, probably from the clay-rich subsoils, such as the argillic horizon, which has been formed by the co-migration of phyllosilicate minerals and relatively crystalline sesquioxides. The species then likely incorporates them into the mounds, which induces an increase in the Fe_d content relative to that of Fe_o, resulting in a decreased iron activity index in the mound structures.  相似文献   

Fish meal vs. corn gluten meal as a protein source for dry cat food.     

M Funaba  T Tanak  M Kaneko  T Iriki  Y Hatano  M Abe 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(12):1355-1357

To compare the effects of two dietary protein sources, fish meal (FM) and corn gluten meal (CGM), fecal moisture content, nitrogen balance and urinary excretion were examined in adult cats. The dietary protein source did not cause a significant difference in daily food intake, water intake, urine volume, dry matter digestibility or urinary nitrogen excretion, but fecal moisture content was lower (P<0.02) in the CGM group. The HCl-insoluble fraction of urinary sediment tended to be higher in the CGM group (P<0.10), although urinary pH was similar in the two groups. These results suggest that CGM is comparable with FM in respect to nutritional value and the urine acidifying effect, but FM may be preferable to CGM for the prevention of constipation and struvite urolithiasis in cats.  相似文献   

Resetting central and peripheral circadian oscillators in transgenic rats     

Yamazaki S  Numano R  Abe M  Hida A  Takahashi R  Ueda M  Block GD  Sakaki Y  Menaker M  Tei H 《Science (New York, N.Y.)》2000,288(5466):682-685

In multicellular organisms, circadian oscillators are organized into multitissue systems which function as biological clocks that regulate the activities of the organism in relation to environmental cycles and provide an internal temporal framework. To investigate the organization of a mammalian circadian system, we constructed a transgenic rat line in which luciferase is rhythmically expressed under the control of the mouse Per1 promoter. Light emission from cultured suprachiasmatic nuclei (SCN) of these rats was invariably and robustly rhythmic and persisted for up to 32 days in vitro. Liver, lung, and skeletal muscle also expressed circadian rhythms, which damped after two to seven cycles in vitro. In response to advances and delays of the environmental light cycle, the circadian rhythm of light emission from the SCN shifted more rapidly than did the rhythm of locomotor behavior or the rhythms in peripheral tissues. We hypothesize that a self-sustained circadian pacemaker in the SCN entrains circadian oscillators in the periphery to maintain adaptive phase control, which is temporarily lost following large, abrupt shifts in the environmental light cycle.  相似文献   

Cartilage acidic protein-1B (LOTUS), an endogenous Nogo receptor antagonist for axon tract formation     

Sato Y  Iketani M  Kurihara Y  Yamaguchi M  Yamashita N  Nakamura F  Arie Y  Kawasaki T  Hirata T  Abe T  Kiyonari H  Strittmatter SM  Goshima Y  Takei K 《Science (New York, N.Y.)》2011,333(6043):769-773

Neural circuitry formation depends on the molecular control of axonal projection during development. By screening with fluorophore-assisted light inactivation in the developing mouse brain, we identified cartilage acidic protein-1B as a key molecule for lateral olfactory tract (LOT) formation and named it LOT usher substance (LOTUS). We further identified Nogo receptor-1 (NgR1) as a LOTUS-binding protein. NgR1 is a receptor of myelin-derived axon growth inhibitors, such as Nogo, which prevent neural regeneration in the adult. LOTUS suppressed Nogo-NgR1 binding and Nogo-induced growth cone collapse. A defasciculated LOT was present in lotus-deficient mice but not in mice lacking both lotus- and ngr1. These findings suggest that endogenous antagonism of NgR1 by LOTUS is crucial for normal LOT formation.  相似文献   

Discovery of a Jupiter/Saturn analog with gravitational microlensing     

Gaudi BS  Bennett DP  Udalski A  Gould A  Christie GW  Maoz D  Dong S  McCormick J  Szymanski MK  Tristram PJ  Nikolaev S  Paczynski B  Kubiak M  Pietrzynski G  Soszynski I  Szewczyk O  Ulaczyk K  Wyrzykowski L;OGLE Collaboration  Depoy DL  Han C  Kaspi S  Lee CU  Mallia F  Natusch T  Pogge RW  Park BG;MuFUN Collaboration  Abe F  Bond IA  Botzler CS  Fukui A  Hearnshaw JB  Itow Y  Kamiya K  Korpela AV  Kilmartin PM  Lin W  Masuda K  Matsubara Y  Motomura M  Muraki Y  Nakamura S  Okumura T  Ohnishi K  Rattenbury NJ  Sako T  Saito T  Sato S 《Science (New York, N.Y.)》2008,319(5865):927-930

Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the detection of a multiple-planet system with microlensing. We identify two planets with masses of approximately 0.71 and approximately 0.27 times the mass of Jupiter and orbital separations of approximately 2.3 and approximately 4.6 astronomical units orbiting a primary star of mass approximately 0.50 solar mass at a distance of approximately 1.5 kiloparsecs. This system resembles a scaled version of our solar system in that the mass ratio, separation ratio, and equilibrium temperatures of the planets are similar to those of Jupiter and Saturn. These planets could not have been detected with other techniques; their discovery from only six confirmed microlensing planet detections suggests that solar system analogs may be common.  相似文献   

Tradition and change in postharvest pest management in Kenya     

Abe Goldman 《Agriculture and Human Values》1991,8(1-2):99-113

The hazard of postharvest pest losses is ubiquitous in peasant farming systems; as a result, farmers invariably have some response to the threat of these losses. Responses to postharvest pests may be more extensive than to field pests, even when, by statistical measures, the usual levels of losses are comparable. In studies of pest management practices in three contrasting areas in Kenya, it was found that farmers virtually always rely on an array of techniques and strategies, usually including both older and more modern practices. There is considerable variation among regions in the techniques used, due not only to climatic and socioeconomic factors, but also to variations in cultural history and preferences. The ways in which management practices have changed over time also vary by region. The major changes have been related to overall system change. Four main sources of change have been paramount: (1) population growth and the intensification of land use; (2) the introduction of new cash crops; (3) the introduction of new marketing infrastructure; and (4) the perception of increased environmental risk. Their effect on the replacement of older practices by newer ones is often interrelated. Traditional techniques are often based on materials derived from bushland, but increasing population density makes these difficult to continue as bushland and its common property resources disappear. Simultaneously, tolerance for losses is reduced as land availability is constrained. With the introduction of a cash crop infrastructure, new methods of pest management, especially pesticide use, become more readily available and may spread rapidly. Areas with good market infrastructure but varying population density may still differ considerably because with abundant land it is possible to compensate for expected losses by additional planting. A study of an FAO project to improve postharvest management through earlier harvesting and a redesigned storage crib indicate some reasons for its lack of widespread acceptance. Little or no attempt was made to adapt techniques to varying circumstances; instead, a single “solution” was meant to be applied across areas of vastly different conditions. In many cases, this project represented a radical response to a problem farmers considered they were coping with acceptably using existing methods. Although it probably represents an improvement over traditional storage methods in purely technical terms, the new technique also often involved major costs, readjustments, and cultural disruptions that may not have been anticipated by its designers. More likely to succeed would be a strategy that begins with some of farmers' existing practices and whose objective is to develop and offer a range of possible improvements from which farmers could select individual components appropriate to their conditions and needs.  相似文献   

Incipient space weathering observed on the surface of Itokawa dust particles     

Noguchi T  Nakamura T  Kimura M  Zolensky ME  Tanaka M  Hashimoto T  Konno M  Nakato A  Ogami T  Fujimura A  Abe M  Yada T  Mukai T  Ueno M  Okada T  Shirai K  Ishibashi Y  Okazaki R 《Science (New York, N.Y.)》2011,333(6046):1121-1125

The reflectance spectra of the most abundant meteorites, ordinary chondrites, are different from those of the abundant S-type (mnemonic for siliceous) asteroids. This discrepancy has been thought to be due to space weathering, which is an alteration of the surfaces of airless bodies exposed to the space environment. Here we report evidence of space weathering on particles returned from the S-type asteroid 25143 Itokawa by the Hayabusa spacecraft. Surface modification was found in 5 out of 10 particles, which varies depending on mineral species. Sulfur-bearing Fe-rich nanoparticles exist in a thin (5 to 15 nanometers) surface layer on olivine, low-Ca pyroxene, and plagioclase, which is suggestive of vapor deposition. Sulfur-free Fe-rich nanoparticles exist deeper inside (<60 nanometers) ferromagnesian silicates. Their texture suggests formation by metamictization and in situ reduction of Fe(2+).  相似文献