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1.
The time has come to proceed from forms of givenness of the word to forms of the word as such. They can, if you like, be called external and inner structures. Humboldt, however, preferred to speak of the external and inner forms of the language. Shpet adopted precisely this distinction. Why did this problem interest Shpet? Already in [Appearance and sense], he had set the task of returning to the source of pretheoretical, living science. Shpet wrote that the outer cover of words and logical expressions obscure the objectified meaning and that it was necessary to remove another cover from the objectified sign so as to grasp a certain genuine intimacy, and in it the fullness of being (Shpet, 1914. Pp. 5-6). We shall keep in mind this major undertaking posed by this scientist. The existence of the inner form of words should not come as a surprise. That same year (1914) Ortega y Gasset wrote that material objects have a third dimension. However, we cannot see or touch it: "For just as depth needs a surface beneath which to be concealed, the surface, or outer cover, in order to be so, needs something over which to spread, covering it" (Ortega y Gasset, 2000. Pp. 62-63).  相似文献   

2.
Summary 1. The material for this study is drawn from two sources, (a) investigations of the fish fauna in the inner Oslofjord between 1897 and 1967, (b) fish landing statistics available since 1872 at the Oslo fish market.2. The investigations of the fish fauna reveal that 4 species of fish — 2 sharks and 2 arctic bullheads — have disappeared from the deep waters of the Oslofjord where they were known to exist in 1897. We assume that unfavourable conditions, great changes in temperature or lack of oxygen in the stagnant deep water to which these species belonged have been injurious to their propagation and survival.3. The annual fluctuations in the landed quantities of fish are great, but nevertheless there exists a marked decreasing trend since about 1930; total landings in recent years are less than 1/10 of what they were 30 or 40 years ago.4. The fluctuations in the landings of cod, herring and mackerel are studied in some detail. Three periods (of 20 to 22 years' duration) from 1872 to 1932 show increasing average landings of cod: 44, 57, and 74 tons respectively; in the period 1933 to 1955 landings decreased to an average of 16 tons per year. The effect of fluctuating year classes is discussed.5. The landings of herring and mackerel were very good between 1911 and 1919 or 1920 with a maximum of 1500 tons of herring and 800 tons of mackerel. In the following years there was a trend of decrease with a few years of moderately good landings. Mature mackerels are immigrating into the fjord for feeding and spawning, while mature herrings, to a major extent, are supposed to belong to a local stock. The highest landings of both species are due to extremely great catches of young fish, and the success of the fishery in any one year, therefore, dependent of a successful spawning and hatching one ort two years before.6. In conclusion, the attention is drawn to the fact that there are reasons to believe that the profuse growth of bacteria in the polluted waters seems to be injurious to the hatching of fish eggs and to the survival of fish larvae (Dannevig 1945,Oppenheimer 1955).
Veränderungen der Fischfauna und der Fischerei des Oslofjords seit der Jahrhundertwende
Kurzfassung Das Material zu dieser Untersuchung stammt aus zwei Quellen: (a) vier Untersuchungen über die Fischfauna des Oslofjords im Zeitraum zwischen 1897 und 1967, und (b) Statistiken für den Zeitraum von 1872 bis 1964 über die Fischmengen, die im inneren Oslofjord gefangen und an die Fischhalle in Oslo geliefert worden sind. Ein Vergleich der Resultate mit den vier Untersuchungen über die Fischfauna zeigt, daß vier Arten von Tiefwasserfischen aus dem inneren Oslofjord völlig verschwunden sind, nämlichEtmopterus spinax, Somniosus microcephalus, Artediellus uncinatus undIcelus bicornis, die beiden zuletzt genannten wahrscheinlich schon vor 1930. Eine Anzahl anderer Arten, die früher häufig waren, sind jetzt selten. Statistische Erhebungen über die im Oslofjord gefangenen Fische lassen erkennen, daß die Erträge seit den zwanziger und dreißiger Jahren stark zurückgegangen sind. Gleichzeitig hat die Zahl der Fischer abgenommen. Es wird die Schlußfolgerung gezogen, daß die Veränderungen des Oslofjords sich besonders in den letzten 30 Jahren für mehrere Fischarten als schädigend erwiesen haben. Diese Auffassung wird unterstützt durch die Untersuchungen vonDannevig (1945) undOppenheimer (1955), die gezeigt haben, daß die reiche Bakterienflora des Oslofjords für die Entwicklung der pelagischen Fischeier schädlich ist.
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3.
4.
Power calculations of a statistical test require that the underlying population distribution(s) be completely specified. Statisticians, in practice, may not have complete knowledge of the entire nature of the underlying distribution(s) and are at a loss for calculating the exact power of the test. In such cases, an estimate of the power would provide a suitable substitute. In this paper, we are interested in estimating the power of the Kruskal-Wallis one-way analysis of variance by ranks test for a location shift. We investigated an extension of a data-based power estimation method presented by Collings and Hamilton (1988), which requires no prior knowledge of the underlying population distributions other than necessary to perform the Kruskal-Wallis test for a location shift. This method utilizes bootstrapping techniques to produce a power estimate based on the empirical cumulative distribution functions of the sample data. We performed a simulation study of the extended power estimator under the conditions of k = 3 and k = 5 samples of equal sizes m = 10 and m = 20, with four underlying continuous distributions that possessed various location configurations. Our simulation study demonstates that the Extended Average × & Y power estimation method is a reliable estimator of the power of the Kruskal-Wallis test for k = 3 samples, and a more conservative to a mild overestimator of the true power for k = 5 samples.  相似文献   

5.
2020 has been one of the craziest and strangest years we have lived through. Now that it’s over, it’s an opportunity to show gratitude for all the good things. Subject Categories: S&S: History & Philosophy of Science

I moved to New York City the year of the attacks on September 11, 2001, one of the bleakest moments in the history of the United States. I was also in New York City when Superstorm Sandy hit in 2012. Luckily, much fewer people died due to the storm, but it was incredibly disruptive to many scientists in the affected area—my laboratory had to move four times over a period of 6 years in the storm’s aftermath. These were awful, tragic events, but 2020 may go down in the record books as one of the most stressful and crazy years in modern times. Not to be outdone, 2021 has started terribly as well with COVID‐19 still ravaging the world and an attack on the US Capitol, something I thought I’d never see in my lifetime. The unnecessary deaths and the damage to America’s “House of the People” were heartbreaking.While these events were surely awful, nothing will be as crushing as the deaths of family members, close friends, and the children of friends; perhaps, it is these experiences—and the death of a beloved dog—that prepared me for this year and made me grateful, maybe even more than usual, for what I have. But in the age of a pandemic, what am I particularly grateful for?I''m ridiculously grateful to have a job, a roof over my head, and food security. The older I get, the more I see illness and injury affect my colleagues, family, and friends, I increasingly appreciate my good health. I am grateful for Zoom (no, I have no investment in Zoom)—not for the innumerable seminars or meetings I have attended, but for the happy hours that helped to keep me sane during the lockdown. Some of these were with my laboratory, others with friends or colleagues, sometimes spread over nine time zones. Speaking of which, I’m also grateful for getting a more powerful router for the home office.I''m immeasurably grateful to be a scientist, as it allows me to satisfy my curiosity. While not a year‐round activity, it is immensely gratifying to be able to go to my laboratory, set up experiments, and watch the results coming in. Teaching and learning from students is an incredible privilege and educating the next generation of scientists how to set up a PCR or run a protein gel can, as a well‐known lifestyle guru might say, spark serious joy. For this reason, I’m eternally grateful to my trainees; their endless curiosity, persistence, and energy makes showing up to the laboratory a pleasure. My dear friend Randy Hampton recently told me he received a student evaluation, thanking him for telling his virtually taught class that the opportunity to educate and to be educated is something worth being grateful for, a sentiment I passed onto a group of students I taught this past fall. I believe they, too, were grateful.While all of the above things focus on my own life, there are much broader things. For one, I am so grateful to all of those around the globe who wear masks and keep their distance and thereby keep themselves and others safe. I am grateful for the election of an American president who proudly wears a mask—often quite stylishly with his trademark Ray‐Ban Aviators—and has made fighting the COVID‐19 pandemic his top priority. President Biden''s decision to ramp up vaccine production and distribution, along with his federal mask mandate, will save lives, hopefully not just in the United States but worldwide.This Gen‐X‐er is also especially grateful to the citizens of Generations Y and Z around the world for fighting for social justice; I am hopeful that the Black Lives Matter movement has got traction and that we may finally see real change in how communities of color are treated. I have been heartened to see that in my adopted home state of New York, our local politicians ensure that communities that have been historically underserved are prioritized for COVID‐19 testing and vaccinations. Along these lines, I am also incredibly encouraged by the election of the first woman who also happens to be of African and Asian heritage to the office of vice president. Times are a changin''...While it is difficult to choose one, top thing to be grateful for, I would personally go for science. I am stoked that, faced with a global crisis, science came to the rescue, as it often has in the past. If I had to find a silver lining in COVID‐19—albeit it would be for the darkest of clouds—I am grateful for all of our colleagues, who despite their usual arguing, quickly and effectively developed tests, provided advice, epidemiological data and a better understanding of the virus and its mode of infection, and ultimately developed therapies and vaccines to save lives. The same can be said for the biotech and pharmaceutical industry that, notwithstanding its often‐noted faults, has been instrumental in developing, testing and mass‐producing efficient and safe vaccines in blistering, record time. Needless to say, I have also much gratitude to all of the scientists and regulators at the FDA and elsewhere who work hard to make life as we once knew it come back to us, hopefully in the near future.Once again, thank you for everything, Science.  相似文献   

6.
7.
Bradford  J. M. 《Hydrobiologia》1988,167(1):73-81
Conflicting systems of classifying the Calanidae (Brodsky, 1972; Bradford & Jillett, 1974) are analysed and a preferred system recommended. Brodsky's system, based on characters with assumed adaptive and functional significance is rejected as is his claim to have produced a phylogenetic scheme. Bradford & Jillett's system, based on a variety of characters, results in a coherent classification which aims to be neutral concerning phylogenetic relationships among genera. Species of Calanoides, Calanus, Nannocalanus, and Neocalanus are surveyed and the need for further taxonomic work is assessed.  相似文献   

8.
This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.  相似文献   

9.
In this work, it has been studied the production of electricity and the oxidation of the pollutants contained in a synthetic wastewater fed with glucose and peptone of soybean as carbon sources, using a mediator-less microbial fuel cell (MFC). Special attention has been paid to the acclimation stage, in which it was found that with high hydraulic and solid retention times it is possible to obtain a very efficient process with a 90% COD removal and practically total conversion of COD into electricity (considering the typical stoichiometric yield of heterotrophic biomass). The influence of concentration sludge was studied working with three different amounts of suspended solids, from 120 to 14000 mg. The maximum power density increased exponentially with the concentration sludge from 2.1 mW m−2 to 11 mW m−2 at the highest concentration sludge. More over, the percentage of the influent COD used to produce electricity was higher than 100% when the highest sludge concentration was used. This was explained taking into account the endogenous metabolism of micro-organisms presented in the system.  相似文献   

10.
Claude Meisch 《Hydrobiologia》2007,585(1):181-200
The posterior end of body of the extant ostracods exhibits a pair of variously shaped appendages, commonly designated as furca(e), uropods or caudal rami, used for feeding and/or locomotion. It is here shown that the so-called furca of all extant ostracods has evolved from the (probably epipodal) vibratory plates of a pair of uropods. The transformation comprised the following steps: (a) complete reduction of the uropodal protopodite and endopodite; (b) sclerotisation of the lateral walls of the vibratory plates; (c) transformation of the branchial filaments into spines and/or claws; (d) re-orientation of the plates from posterodorsal to posteroventral. These modifications are suggested to have evolved in parallel with a change in function, from respiratory to locomotory and/or feeding. The most primitive condition, reminiscent of the ancestral state of character, is seen in the Platycopida: the ‘furca’ still appears similar in shape to the vibratory plates of the pair of sixth limbs. In the Podocopida the uropodal plates have been modified into plate-like, more often into rod-shaped rami mainly used for locomotion. In both the Platycopida and Podocopida the anus has remained in its original place, posterior to the ‘furcal’ plates or rami. In the Myodocopida and Halocyprida the uropodal vibratory plates are transformed into heavily developed lamellae bearing sturdy spines. They are activated by a complex apparatus of muscles and sclerites, the development of which necessitated the displacement of the anus from the end of the body towards its present place, anterior to the ‘furca’. The furca of the Ostracoda being not a ‘true’ furca, a change in terminology is proposed: uropodal plates or lamellae in the Platycopida, Palaeocopida and Myodocopida/Halocyprida; uropodal rami in the Podocopida. The so-called furcae of the Ostracoda being homologous structures, it is concluded that all extant ostracods belong to a monophyletic lineage.  相似文献   

11.
Abstract

We report here the parallel implementation of an original algorithm allowing a fast calculation of the distance matrix D of a graph representing a given chemical structure (molecule, polymer, crystal, etc.). Our algorithm fits perfectly in the SIMD parallel architecture of the Connection Machines CM-200 as we shall show. After discussing the performances of the parallel evaluation of D, we will end with a relevant application concerning C60 and C70 fullerenes. The present study applies to a generic globally connected graph without any restriction on the local connectivity of each graph's vertex.  相似文献   

12.
Summary The statocyst ofPecten is composed of hair cells and supporting cells. The hair cells bear kinocilia and microvilli at their distal ends and the supporting cells bear microvilli. The cilia have a 9+2 internal filament content, and arise from basal bodies that have roots, basal feet and microtubular connections. Two different ciliary arrangements are described, one with a small number of cilia arranged in a ring, and another with many more cilia arranged in rows. Below the hair cells are probable synapses. A ciliated duct connects to the lumen of the static sac and passes through the centre of the static nerve. The hair cells in the statocyst ofPterotrachea bear kinocilia and microvilli. The possible importance of cilia and microvilli in the transduction process is discussed.We would like to thank ProfessorJ. Z. Young for bringing specimens ofPterotrachea from Naples and also the staff of the Stazione Zoologica for the provision of specimens, Dr.M. Land for providing specimens ofPecten, the Science Research Council (U.K.) for providing the electron microscope used in much of the study and also for a grant to one of us (V.C.B.), and Mrs.J. Parkers and Mr.R. Moss and Mrs.J. Hamilton for much photographic and technical assistance.  相似文献   

13.
BELL  P. R.; ZAFAR  A. H. 《Annals of botany》1961,25(4):531-546
Estimations of the amounts of organic nitrogen in spores anddeveloping gametophytes of Dryopteris borreri, a fern reproducingapogamously and lacking archegonia, have shown that the nitrogenin the gametophytes increases exponentially. The logarithmicrate of increase of the nitrogen remains unchanged during theinitiation and emergence of the sporophyte. Gametophytes aboutto produce sporophytes yielded only filamentous growths whentransferred to a medium containing 8-azaguanine, and the increasein their content of organic nitrogen was very small. The resultsare discussed in relation to similar estimations made by otherworkers upon the gametophytes of Dryopteris erythosora(Eat.)Schott, a fern reproducing sexually. The interpretation placedupon the results obtained for D. erytkrosora is questioned,and a new interpretation of these results, together with thosefor D. borreri, is related to the difference in morphology ofthe two generations in the life cycle of the Polypodiaceousferns.  相似文献   

14.
Pancreas lobules incubated in vitro actively incorporate (2-3H) myoinositol into the PI associated with a number of different membranes, i.e., those of the rough- and smooth-surfaced microsomes, mitochondria, zymogen granules, as well as the plasmalemma. Stimulation of secretion with Acetylcholine + Eserine results in an increase of the incorporation (PI effect). This increase is approximately of the same order of magnitude (~ 4fold) in all the fractions. The results might be due either to a generalized breakdown of the PI associated with all the membranes under study, followed by resynthesis, or to a rapid intracellular redistribution of the PI molecules, synthetized in response to the stimulation.  相似文献   

15.

Background  

The coevolution theory of the origin of the genetic code suggests that the genetic code is an imprint of the biosynthetic relationships between amino acids. However, this theory does not seem to attribute a role to the biosynthetic relationships between the earliest amino acids that evolved along the pathways of energetic metabolism. As a result, the coevolution theory is unable to clearly define the very earliest phases of genetic code origin. In order to remove this difficulty, I here suggest an extension of the coevolution theory that attributes a crucial role to the first amino acids that evolved along these biosynthetic pathways and to their biosynthetic relationships, even when defined by the non-amino acid molecules that are their precursors.  相似文献   

16.
Scaffolding proteins can customize the response of signaling networks to support cell development and behaviors. PleC is a bifunctional histidine kinase whose signaling activity coordinates asymmetric cell division to yield a motile swarmer cell and a stalked cell in the gram-negative bacterium Caulobacter crescentus. Past studies have shown that PleC’s switch in activity from kinase to phosphatase correlates with a change in its subcellular localization pattern from diffuse to localized at the new cell pole. Here we investigated how the bacterial scaffolding protein PodJ regulates the subcellular positioning and activity of PleC. We reconstituted the PleC-PodJ signaling complex through both heterologous expressions in Escherichia coli and in vitro studies. In vitro, PodJ phase separates as a biomolecular condensate that recruits PleC and inhibits its kinase activity. We also constructed an in vivo PleC-CcaS chimeric histidine kinase reporter assay and demonstrated using this method that PodJ leverages its intrinsically disordered region to bind to PleC’s PAS sensory domain and regulate PleC-CcaS signaling. Regulation of the PleC-CcaS was most robust when PodJ was concentrated at the cell poles and was dependent on the allosteric coupling between PleC-CcaS’s PAS sensory domain and its downstream histidine kinase domain. In conclusion, our in vitro biochemical studies suggest that PodJ phase separation may be coupled to changes in PleC enzymatic function. We propose that this coupling of phase separation and allosteric regulation may be a generalizable phenomenon among enzymes associated with biomolecular condensates.  相似文献   

17.
Summary The rate of shrinkage of the mucosal folds of goldfish intestine in response to mucosal hypertonicity was measured by microscopic means. Because of the geometry of the intestinal folds the rate of shrinkage could be directly related to the loss of volume from the fold through the brush border membranes and tight junctions. Experimentally a wide range of velocities was observed, reflecting the difficulty of rapidly estabilishing a uniform osmotic gradient at the preparation's mucosal surface. The initial velocity of volume loss provided a measure of the filtration permeability (P f ) of the mucosal surface. From the highest velocities observed the filtration permeability was estimated to be approximately 14×10–3 cm/sec related to the folded mucosal surface and 65×10–3 cm/sec related to the straight serosal surface. Consideration of the experimental errors and unstirred layer effects make it probable that the latter value is still an underestimate of the trueP f . The series barriers of the epithelium cause the total tissueP f to be less than theP f of the mucosal surface alone. In addition theP f measured in the presence of an osmotic gradient may differ substantially from the tissue filtration permeability which exists in the absence of a change in osmolarity.  相似文献   

18.
Gypsy is an endogenous retrovirus present in the genome of Drosophila melanogaster. This element is mobilized only in the progeny of females which contain active gypsy elements and which are homozygous for permissive alleles of a host gene called flamenco (flam). Some data strongly suggest that gypsy elements bearing a diagnostic HindIII site in the central region of the retrovirus body represent a subfamily that appears to be much more active than elements devoid of this site. We have taken advantage of this structural difference to assess by the Southern blotting technique the genomic distribution of active gypsy elements. In some of the laboratory Drosophila stocks tested, active gypsy elements were found to be restricted to the Y chromosome. Further analyses of 14 strains tested for the permissive vs. restrictive status of their flamenco alleles suggest that the presence of permissive alleles of flam in a stock tends to be associated with the confinement of active gypsy elements to the Y chromosome. This might be the result of the female-specific effect of flamenco on gypsy activity. Received: 13 June 1997 / Accepted: 27 August 1997  相似文献   

19.
Physcomitrella patens, belonging to bryopsida, is a basal lineage of land plants. To gain insight into the diversification of the two-component system (TCS), which is widely conserved from prokaryotes to eukaryotes, we compiled TCS-associated genes by employing P. patens genome databases. The moss has a set of His-kinases (HKs), including homologs of the cytokinin- and ethylene-receptors in seed plants. In addition, it has a number of coding-sequences specifying unique HKs. We found evidence that a putative cytokinin-receptor HK in P. patans serves as a sensor for this hormone, and that the HK activity of a putative ethylene-receptor homolog is regulated by ethylene, as observed for Arabidopsis thaliana.  相似文献   

20.
This study proposes to estimate the horizontal positions of the body's centre of gravity (CoG) in a standing posture, on the basis of the horizontal positions of the centre of pressure (CoP). The latter were measured with a force plate, and using a low-pass filter defined by a mathematical relationship of the relative magnitude of the CoG with respect to the magnitude of the CoP, as a function of the frequency oscillations (Brenière, 1996, Journal of Motor Behaviour 28, 291–298). This relationship was computed from the angular momentum equation applied to the whole body with respect to the CoG using the inverse dynamics approach and force plate recordings, and considering the CoP and CoG oscillations as simple periodic functions. Five subjects were asked to perform voluntary oscillations along medio-lateral and antero-posterior axes, keeping their bodies straight, and without moving their feet. The CoG accelerations measured by the force plate were compared with the CoG accelerations derived from the estimated CoG positions. The average root-mean-square difference between these accelerations was very small, confirming the accuracy of this method. This simplified way to calculate the CoG positions, rarely measured in standing, allows a comparative assessment of motion performance. This method could also be applied to other kinds of movement such as walking.  相似文献   

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