Analysis of exchanges in differentially stained meiotic chromosomes of Locusta migratoria after BrdU-substitution and FPG staining

The strand relationships of adjacent pairs of chiasmata have been examined in differentially stained meiotic bivalents following in vivo BrdU substitution and FPG staining. A test for chromatid interference is described, based on comparisons of the observed numbers of various combinations of hidden and visible crossover exchanges with the numbers expected assuming no chromatid interference. A comparison based on 67 pairs of chiasmata from Locusta migratoria indicates no evidence for chromatid interference in this material.     

The association of the human ε-globin gene with the nuclear matrix: a reconsideration

The association of the human -globin gene with the nuclear matrix was studied in erythroid and non-erythroid cell lines. Using a high salt method to prepare histone depleted nuclei we studied the association of variety of fragments covering a 7.8 kb region which contains the human -globin gene. We furthermore studied the association of a set of DNA fragments covering the 13 kb human G/A-globin gene domain, the 16 kb /-globin gene domain and the 10 kb -globin gene domain with the nuclear matrix of K562 and Raji cells. The results show that all fragments studied are easily released from the nuclear matrix, indicating no specific association.Summarizing our results we could say that a region starting 5.7 kb 5 to the human -globin gene and ending 4 kb 3 to the human -globin gene seems to contain no attachment sites with the nuclear matrix of both erythroid and non-erythroid cells.     

Secondary structural effects on protein NMR chemical shifts

For an amino acid in protein, its chemical shift, (, )_s, is expressed as a function of its backbone torsion angles ( and ) and secondary state (s): (, )_{s=, )_coil+(, )_s}, where (, )_coil represents its chemical shift at coil state (s=coil); (, )_s (s=sheet or helix) is herein defined as secondary structural effect correction factor, which are quantitatively determined from Residue-specific Secondary Structure Shielding Surface (RSS) for ¹³CO, ¹³C, ¹³C,¹H, ¹⁵N, and ¹HN nuclei. The secondary structural effect correction factors defined in this study differ from those in earlier investigations by separating out the backbone conformational effects. As a consequence, their magnitudes are significantly smaller than those earlier reported. The present (, )_sheet and (, )_helix were found varying little with backbone conformation and the 20 amino acids, specifically for ¹³CO, ¹³C, and ¹H nuclei. This study also carries out some useful investigations on other chemical shift prediction approaches – the traditional shielding surfaces, SHIFTS, SHIFTX, PROSHIFT, and identifies some unexpected shortcomings with these methods. It provides some useful insights into understanding protein chemical shifts and suggests a new route to improving chemical shifts prediction. The RSS surfaces were incorporated into the program PRSI [Wang and Jardetzky, J. Biomol. NMR, 28: 327–340 (2004)], which is available for academic users at http://www.pronmr.com or by sending email to the author (yunjunwang@yahoo.com).     

Etude ultrastructurale des corpora cardiaca et de quelques formations annexes chez Locusta migratoria L.

Résumé Les corpora cardiaca de l'adulte de Locusta migratoria sont formés de deux régions bien individualisées ce qui nous a permis de reconnaître la sécrétion propre des différents types de neurosécrétion. Dans la région nerveuse, nous distinguons par la taille des grains trois types de neurosécrétion dense classique et un quatrième type d'aspect clair. Dans la région »propre« non nerveuse, les cellules ont des caractères nettement endocriniens et sont mélangées à un seul type d'axones neurosécréteurs.

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Ultrastructural study of the corpora cardiaca and affiliated structures in Locusta migratoria L.

Summary The corpora cardiaca of adult Locusta migratoria consist of two well separated areas, a fact which permits the differentiation between intrinsic and extrinsic neurosecretory material. In the neural area three types of electron dense classical neurosecretory granules, and a fourth more lucent type can be distinguished according to size. In the non-neural glandular area typical endocrine cells mingle with only one type of neurosecretory axons.

     

Synthesis of disaccharide derivatives employing β-N-acetyl- d-hexosaminidase, β-d-galactosidase and β-d-glucuronidase

-N-Acetyl-d-hexosaminidase from Aspergillus oryzae catalysed the stereo- and regiospecific formation of the 6-O-benzylated disaccharide derivatives GalNAc1-3(6- OBn)Gal-SEt and GlcNAc1-3(6-OBn)Gal-SEt, which were obtained in transglycosylation reactions employing ethyl 6- O-benzyl-1-thio--d-galactopyranoside as acceptor. Preparative amounts of the chitobiose derivative GlcNAc1- 3GlcNAc-OPhNO2-p was prepared as well. - N-Acetyl-d-hexosaminidase from bovine testes catalysed the specific synthesis of GlcNAc1-3(6-OBn)GlcNH2-SEt and GalNAc1-3(6-OBn)GlcNH2-SEt, employing ethyl 2-amino-6-O-benzyl-2-deoxy-1-thio--d-glucopyranoside as acceptor. -d-Glucuronidase from E. coli was found to catalyse the formation of GlcA1-3(6-OBn)GlcNH2- SEt employing the same acceptor.     

A unified matrix hypothesis of DNA-directed morphogenesis,protodynamism and growth control

A theoretical concept is proposed, in order to explain some enigmatic aspects of cellular and molecular biology of eukaryotic organisms. Among these are the C-value paradox of DNA redundancy, the correlation of DNA content and cell size, the disruption of genes at DNA level, the Chromosome field data of Lima de Faria (Hereditas 931, 1980), the quantal mitosis proposition of Holtzeret al. (Curr. Top. Dev. Biol. 7229 1972), the inheritance of morphological patterns, the relations of DNA and chromosome organisation to cellular structure and function, the molecular basis of speciation, etc. The basic proposition of the Unified Matrix Hypothesis is that the nuclear DNA has a direct morphogenic function, in addition to its coding function in protein synthesis. This additional genetic information is thought to be largely contained in the non-protein coding transcribed DNA, and in the untranscribed part of the genome.In this world, seeds of different kinds, sown at the proper time in the land, even in one field, come forth (each) according to its kind.In the biological sense, the term Matrix is used here to signify the integrity of the cell's fibrous networks in nucleus and cytoplasm, during interphase and metaphase. In the philosophical sense, Matrix Hypothesis integrates also the etymological meaning of the term, which stems from mater (i.e. origin), and means also a lattice within a frame of coordinates, or else: Something (as a surrounding or pervading substance or element) within which something else originates or takes form or develops (cf. Webster's Intern. Dict.).—The term Protodynamism was defined earlier (Scherrer, 1966) as meaning the integrity of theorganised movements of the cellular components, excluding mere diffusion.A preliminary version of this assay was published previously (cf. Scherrer, 1985).     

NADH dehydrogenase: a new molecular marker for homoeology group 4 in Triticeae. A map of the 4RS chromosome arm in rye

Summary Structural gene loci encoding the monomeric isozymes nicotin adenin dinucleotide dehydrogenase (NADH dehydrogenase or NDH) have been located on the 4AL, 4B, and 4DS chromosome arms of Triticum aestivum cv Chinese Spring, on the 4RS chromosome arm of Secale cereale cultivars Imperial, King II, Dakold, and Ailes, on the 4S¹ S/7S¹ chromosome of Aegilops longissima, the 4E of Elytrigia elongata, and the CSU-A of Aegilops umbellulata. All the results support the homoeologous relationships among these chromosomes in the five species studied. In addition, a map of the 4RS chromosome arm in cv Ailes has been realized, linking loci Pgm-1 (located on the 4RS chromosome arm) and Ndh-1 (17.91 cM), with an estimated distance between both loci and the centromere of 20.00 cM and 32.12 cM, respectively.     

Benzyl-N-acetyl-α-d-galactosaminide inhibits the sialylation and the secretion of mucins by a mucin secreting HT-29 cell subpopulation

We have analysed the mucins synthesized by the HT-29 MTX cell subpopulation, derived from the HT-29 human colon carcinoma cells through a selective pressure with methotrexate (Lesuffleuret al., 1990,Cancer Res 50: 6334–43), in the presence of benzyl-N-acetyl--galactosaminide (GalNAc-O-benzyl), which is a potential competitive inhibitor of the 1,3-galactosyltransferase that synthesizes the T-antigen. The main observation was a 13-fold decrease in the sialic acid content of mucins after 24 h of exposure to 5mm GalNAc-O-benzyl. This effect was accompanied by an increased reactivity of these mucins to peanut lectin, testifying to the higher amount of T-antigen. The second observation was a decrease in the secretion of the mucins by GalNAc-O-benzyl treated cells. The decrease in mucin sialyation was achieved through thein situ -galactosylation of GalNAc-O-benzyl into Gal1–3GalNAc-O-benzyl, which acts as a competitive substrate of Gal1–3GalNAc 2,3-sialyltransferase, as shown by the intracellular accumulation of NeuAc2–3Gal1–3GalNAc-O-benzyl in treated cells.Abbreviations BSM bovine submaxillary mucin - MTX methotrexate - PBS sodium phosphate 10mm, NaCl 0.15m, pH 7.4 buffer - pNp p-nitrophenol - TBS Tris/HCl 10mm, NaCl 0.15m, pH 7.4 buffer Enzymes: CMP-NeuAc: Gal1–3/4GlcNAc 2,3-sialyltransferase, ST3(N), EC 2.4.99.6; CMP-NeuAc: Gal1–4GlcNAc 2,6-sialyltransferase, ST6(N), EC 2.4.99.1; CMP-NeuAc: Gal1–3GalNAc 2,3-sialyltransferase, ST3(O), EC 2.4.99.4; CMP-NeuAc: R-GalNAc1-O-Ser 2,6-sialyltransferase, ST6(O)-I, EC 2.4.99.3; CMP-NeuAc: NeuAc2–3Gal1–3GalNAc 2,6-sialyltransferase, ST6(O)-II, EC 2.4.99.7; UDP-GlcNAc: Gal1–3GalNAc-R·(GlcNAc to GalNAc) 1,6-N-acetylglucosaminyltransferase, EC 2.4.1.102; UDP-GlcNAc: GalNAc-R 1,3-N-acetylglucosaminyltransferase, EC 2.4.1.147; UDP-Gal: GalNAc-R 1,3-galactosyltransferase, EC 2.4.1.122.     

Comparative residual toxicities of pesticides to the predator Agistemus industani (Acari: Stigmaeidae) on citrus in Florida

Residual toxicities of registered and selected experimental pesticides used on citrus against Agistemus industani Gonzalez (Acari: Stigmaeidae) were compared. Pesticides considered highly toxic to A. industani were: abamectin 0.15 EC at 731ml/ha+FC 435-66 petroleum oil at 46.8l/ha, pyridaben 75WP at 469g/ha, ethion 4EC at 7.01l/ha+FC 435-66 petroleum oil at 46.8l/ha, propargite 6.55 EC at 3.51l/ha, chlorfenapyr 2SC at 1.46l/ha applied alone or in combination with FC 435-66 petroleum oil at 46.8l/ha, sulphur 80DF at 16.81kg/ha, dicofol 4EC at 7.01l/ha, fenbutatin oxide 50WP at 2.24kg/ha, benomyl 50WP at 2.24kg/ha, benomyl 50WP at 1.68kg/ha+ferbam 76 GF at 5.60kg/ha, ferbam 76GF at 11.21kg/ha, neem oil 90EC at 46.8l/ha, and copper hydroxide DF (40% metallic copper) at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha. Pesticides that were moderately to slightly toxic included: copper sulphate 98% at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha, fenbuconazole 2F at 280ml/ha+FC 435-66 petroleum oil at 46.8l/ha, FC 435-66 petroleum oil applied alone at 46.8l/ha or 23.4l/ha, and diflubenzuron 25WP at 1.40kg/ha. Pesticides that were non-toxic included: fenbuconazole 2F at 585ml/ha, malathion 57EC at 5.85l/ha, FC 435-66 petroleum oil at 46.8l/ha, carbaryl 80S at 3.36kg/ha, chlorpyrifos 4EC at 4.68l/ha, and formetanate 92SP at 1.12kg/ha. Understanding the toxic effects of field weathered pesticides against key predacious mite species is important for effective IPM. The results of this study provide a comparison of direct and indirect toxic effects of various pesticides to A. industani under field conditions.     

Alkaline lipolytic activity of rabbit adipose tissue: Genotypes and their inheritance

A genetic variant of alkaline lipolytic activity (ALA), a soluble esterase found in mammalian adipose tissue, has previously been described. This slow variant was characterized by slower migration during starch gel electrophoresis, a decreased tendency to dimerize, and reduced enzymatic activity in constrast to the fast electrophoretic phenotype. The present paper identifies a homozygous (FF) and a heterozygous (Ff) fast phenotype which are differentiated after starch gel electrophoresis by the presence or absence of a slow band identical to that of the homozygous slow (ff)/it phenotype. In addition, ALA of homozygous and heterozygous fast rabbits differed in total enzymatic activity and its tendency to dimerize. The inheritance of this variant was proven to be Mendelian.This work was supported in part by United States Public Health Service Grants AM-06872 from the National Institute of Arthritis and Metabolic Diseases and GM-15874 from the National Institute of General Medical Sciences; and Project #417 of the Children's Bureau, Department of Health, Education and Welfare.     

Expression of α and β tropomyosin subunits during early myogenesis in somites and limb buds of chick embryos

Summary The appearance of and subunits of skeletal tropomyosin in early myogenesis was studied histochemically using monoclonal antibody to tropomyosin and affinity-purified polyclonal antibody to tropomyosin. In muscle cells, in both somites and limb buds, the and subunits are simultaneously expressed and first appear in the somites at the 30–36 somites. The relatively greater amount of than tropomyosin found in early myogenesis is thus likely to result from a higher rate of tropomyosin synthesis.     

Der „biologische Aufstieg“ und seine Kriterien

Zusammenfassung Die Arbeit stellt die Frage nach den Kriterien des fossil belegten Biologischen Aufstiegs der Organismenwelt, d.h. derjenigen Vervollkommnung, die sich nicht innerhalb des Rahmens eines gegebenen Bauplans hält, wie die Anpassungsvervollkommnung, sondern über verschiedenrangige Baupläne hinweg zu höheren Typen führt, z.B. von den Fischen über die Amphibien und Reptilien zu den Säugern bzw. Vögeln. Ausführlich werden zwei Gruppen von Kriterien besprochen, ihr Inhalt dargelegt und ihre Eindeutigkeit zur Charakterisierung des Biologischen Aufstiegs untersucht. Die erste Gruppe umfasst die Kriterien der zunehmenden Differenzierung und harmonischeren Integration. Diese legen die morphologisch-physiologische Differenzierung oder genauer die Ganzheit der Organismen zugrunde, d.h. ihre Vielheit in der Einheit. Die zweite Kriteriengruppe, nämlich zunehmende Umweltunabhängigkeit und zunehmende individuelle Autonomie, geht von den Beziehungen des Organismus zur Umwelt und zu andern Lebensformen aus und betont die Subsistenz der Individuen, d.h. ihr grösseres oder geringeres Losgelöstsein oder ihre Selbständigkeit. Da nun Ganzheit und Subsistenz die entscheidenden Elemente einer biologischen Definition des Individuums sind, lässt sich sagen, dass der Biologische Aufstieg eines Organismus um so höher ist, je stärker seine Ganzheit und Subsistenz und damit sein Individuumsein ist.Eindeutigkeit kommt allen genannten Kriterien nicht zu. Die Gründe für ihre Unschärfe sind verschiedener Art. Zunächst gibt es noch keine eindeutige und vollständige Definition des biologischen Individuums, so dass sich nicht eindeutig umreissen lässt, was einem Organismus eine stärkere oder weniger starke Individualität verleiht. Dann sind die Linien, über die sich Vervollkommnungen vollziehen und von denen die eine innerhalb des Bauplans bleibt (Anpassungsvervollkommnung), die andere aber über ihn hinausführt (Biologischer Aufstieg) so innig und in so eigenartiger Weise miteinander verflochten, dass sie sich nicht sauber scheiden und in ihren charakteristischen Merkmalen genau beschreiben lassen. Jeder Vertreter eines Bauplans, ganz gleich von welcher Ranghöhe, ist nämlich notwendig in eine Umwelt eingepasst und irgendwie spezialisiert. Es gibt keine Typen mit reinen Bauplanmerkmalen, die nach keiner Richtung hin eine Anpassungsvervollkommnung, sondern nur Merkmale des Biologischen Aufstiegs aufweisen. Schliesslich kennen wir fossil nur die Entfaltung oder Ausgestaltung der Grossbaupläne des Tierreichs, nämlich des Wirbeltierstammes und der verschiedenen Gruppen der Wirbellosen, nicht aber das Interessanteste und Wichtigste, nämlich ihren Biologischen Aufstieg zu der organisatorischen Höhe, mit der sie sich im Silur bzw. im Kabrium bereits vorstellen. Das erst würde einen tieferen Einblick in das Wesen des Biologischen Aufstiegs vermitteln.

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Summary This article deals with the question of the criteria for the biological ascent (Biologischer Aufstieg) of the organic world, resting on fossil evidence. That is, of that improvement which is not only restricted to the framework of a given general structure (Bauplan) as is the improvement of adaptation, but which also leads beyond general structures (Baupläne) of differentiated levels to a higher type,e.g. from the fishes through the amphibians and reptiles to the mammals or birds. Two groups of criteria are discussed at length, their content exposed and their univocity for the characterisation of this biological ascent is examined. The first group includes the criteria of increasing differentiation and more harmonious integration. The basis for these is the morphological-physiological differentiation, or more exactly, the totality of the organisms,i.e., their variety-in-unity. The second group of criteria, increasing independence of environment and increasing individual autonomy, is derived from the relationships of the organism to its environment and to other living forms, and stresses the subsistence of individuals,i.e., their greater or lesser degree of independence or self-sufficiency. Now since totality and subsistence are the decisive elements in a biological definition of the individual, it may be said that the biological ascent of an organism is higher, the more perfect its totality and subsistence and therefore its individuality is.The criteria mentioned are not univocal. The reasons for this lack of clarity are varied. First of all, there is no univocal and complete definition of the biological individual, so that it cannot be exactly stated just what gives an organism a more or less perfect individuality. Then the lines, along which improvements are made, and according to which the one remains within the general structure (improvement of adaptation) and the other goes beyond the general structure (biological ascent), are so intimately and singularly bound together, that they cannot be cleanly distinguished, and their characteristic notes exactly described. For each representative of a general structure, regardless of its level, is necessarily fitted into an environment and somehow or other specialised. There are no types with only notes of the general structure which show in no direction an improvment of adaption, but only the signs of biological ascent. Finally, we only have fossil evidence for the development or deployment of the great general structures (Grossbaupläne) of the animal world, namely that of the vertebrates and of the different groups of invertebrates, not for the most interesting and most important, that is, their biological ascent to the level of organisation with which they are found in the Silurian or Cambrian periods. Only that would give us a deeper insight into the essence of biological ascent.

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Résumé Ce travail pose la question des critères de la progression biologique (Biologischer Aufstieg), d'après les documents fossiles, dans le monde des organismes, c'est-à-dire de ce perfectionnement qui ne s'arrête pas à l'intérieur du cadre d'un phylum (Bauplan) donné, comme le perfectionnement de l'adaptation, mais qui conduit, au-de-là de phylums (Baupläne) de rang différent, à des types supérieurs, par exemple, des Poissons pas les Amphibies et les Reptiles jusqu'aux Mammifères ou aux Oiseaux. Deux groupes de critères y sont recensés en détail, leur contenu est exposé, et on les examine pour voir s'ils caractérisent sans ambiguïté la progression biologique. Le premier groupe comprend les critères de différenciation croissante et d'intégration harmonique. Ils sont fondés sur la différenciation morphophysiologique ou plus exactement sur la totalité des organismes, c'est-à-dire leur multiplicité dans l'unité. Le second groupe de critères, à savoir indépendance croissante du milieu et autonomie individuelle croissante, part des relations de l'organisme au milieu et aux autres formes vivantes et souligne la subsistence des individus, c'est-à-dire leur plus ou moins grande indépendence ou leur stabilité interne. Comme totalité et subsistence sont les éléments décisifs d'une définition biologique de l'individu, on peut dire que la progression biologique d'un organisme est d'autant plus élevée que sa totalité et subsistence et par là son être individuel sont plus accusés.Tous les critères mentionnés ne sont pas uniformes. Les motifs de leur imprécision sont divers. Tout d'abord, il n'y a pas encore de définition unique et complète de l'individu biologique, de sorte qu'on ne peut circonscrire d'une manière univoque ce qui confère à un organisme une individualité plus forte ou moins forte. Ensuite les lignées au-delà desquelles s'accomplissent des perfectionnements, et dont l'une reste intérieur au phylum (perfectionnement de l'adaptation), tandis que l'autre le transcende (progression biologique), sont entrelacées si intimement et d'une façon si particulière qu'elles ne se laissent pas séparer franchement et décrire rigoureusement selon leurs signes distinctifs. Tout représentant d'un phylum, peu importe son palier, est en effet nécessairement inséré dans un milieu et en quelque façon spécialisé. Il n'existe pas des types à caractères phylétiques purs, qui ne montrent dans aucune direction un perfectionnement de l'adaptation, mais seulement des marques caractéristiques de la progression biologique. Enfin nous ne connaissons pas les restes fossiles que le développement ou la formation des grands phylums (Grossbaupläne) du règne animal, à savoir du rameau des Vertébrés et des divers groupes des Invertébrés, mais non pas le plus intéressant et le plus important, leur progression biologique jusqu'au degré d'organisation qu'ils présentent déjà à l'époque du Silurien ou plutôt du Cambrien. C'est cela seulement qui permettrait une vue plus profonde sur la nature de la progression biologique.

     

Shoot organogenesis and plant regeneration in mulberry (Morus bombycis Koidz): Factors influencing morphogenetic potential in callus cultures

Regeneration of multiple shoots via callus induction and organogenesis was achieved in mulberry (Morus bombycis). Pre-soaked internodal explants in 4.4–8.9 M benzyladenine (BA) formed callus on Linsmaier and Skoog's medium containing 2,4-dichlorophenoxyacetic acid (9.05 M), -naphthaleneacetic acid (2.85 M) and BA (2.2 M). Explants soaked for 48 to 72 h in low levels of BA produced loose and nodular callus that showed regeneration ability. Calluses developed adventitious shoot buds within 3–4 weeks on medium containing BA (8.9 M). Fifteen-week-old calluses developed fewer shoot buds than five-week-old calluses, indicating a decrease in morphogenetic potential with increasing duration of callus cultures. Semi-thin section microscopy was used to evaluate incapability of sustained regeneration. Development of normal shoot bud primordia, due to sub-surface reorganisation, was high in young calluses. The decline in the frequency of shoot bud primordia formation with callus ageing is due to reduced cell division activity in epidermal as well as sub-epidermal layers.     

The pancreatic islets of the teleost Scorpaena scropha

Summary The principal pancreatic islets of the teleost Scorpaena scropha are found ultrastructurally to contain four different kinds of parenchymal cells, viz. ₁-(= D), ₂-, -and agranular cells. The -cells show considerable variations in the shape of the secretory granules. A peculiar feature is that many of these granules are composed of fibrillar subunits, often in parallel arrangement. All -granules are surrounded by membranes and between the membrane and the granule core there is a moderately wide electron lucent space. The electron density of the cytoplasm in the -cells varies somewhat. The ₂-cells possess typical secretory granules with an electron dense core and a closely applied membrane. The secretory granules in the ₁-cells show also a closely applied membrane but a less dense core. Also in the -cells the electron opacity of the cytoplasm varies. The agranular cells are mainly characterized by low cytoplasmic electron density, narrow cisterns of endoplasmic reticulum and sometimes a laminated Golgi complex. Small immature secretory granules are occasionally seen in the cytoplasm of these cells. The significance of the fibrillar -granules remains obscure.This work was supported by grants from the Nordic Insulin Fund, the Town of Umeå, the Swedish Medical Research Council (Project No. B69-12X-718-04A), and by a postdoctoral fellowship from the United States Public Health Service.     

The tryptic peptide composition of the beta chains of hemoglobins A and B of the domestic cat (Felis catus)

Summary The tryptic peptides from the ^A and ^B chains of cat hemoglobins A and B have been isolated and the amino acid compositions determined. Differences between the two chains were found in two peptides,T-1 (GlySer) andT-14 (AsnSer and LysArg). The GlySer and LysArg substitutions are placed at-1 and-144 respectively from earlier work, and the third substitution, AsnSer at-139 is suggested from this work. In addition, the presence of a blocked amino terminus in ^B has been confirmed. Tentative sequences constructed by homology with known-chain structures suggest the occurrence of substitutions at _{1 1} contacts in ^A and ^B that may be functionally significant. There are at least 18 differences in amino acid composition between cat ^A and dog-chains and 22 differences between cat ^A and normal adult human-chains.     

Acclimation of the Sea Cucumber Apostichopus japonicus to Decreased Salinity at the Blastula and Gastrula Stages: Its Effect on the Desalination Resistance of Larvae at Subsequent Stages of Development

Apostichopus (= Stichopus) japonicus blastulae and gastrulae were acclimated for 18 h to salinities of 32 (control), 24 and 22 (the lower limit of the range of tolerance), and 20 (below the range of tolerance). Acclimation to 20 resulted in the appearance of teratic larvae, most of which subsequently died. Acclimation to 24, 22, and 20 led to a shift in the range of tolerance of the larvae at further stages of development. With a decrease in salinity, acclimated larvae developed more successfully than unacclimated larvae. Acclimated larvae attained the pentactula stage and settled at a salinity range of 32–20; unacclimated larvae, at 32–22. At different stages of development, acclimated larvae survived greater decreases in salinity than unacclimated larvae. The acclimation effects could be traced up to metamorphosis and settling, i.e., two weeks after the end of the acclimation process.     

Injury to potato leaves exposed to subzero temperatures in the absence of freezing

Electrolyte leakage was measured in hardened and nonhardened leaves of three potato species, Solanum tuberosum L., S. acaule Bitt. and S. commersonii Dun., and one interspecific cross, Alaska Frostless (S. acaule x S. tuberosum) when exposed to various subzero temperatures. The leaves were undercooled (no ice present) from 0°C to -12.5°C for 45 min and to-4°C for up to 10 d. Regardless of the degree of undercooling no injury was observed in any of the potatoes, hardened or nonhardened, for up to 12 h. After 5 d, however, electrolyte leakage was observed in hardened S. tuberosum, S. acaule and S. commersonii, and in nonhardened Alaska Frostless. After 10 d exposure all potatoes, hardened and nonhardened, showed a significant amount of electrolyte leakage as compared to their controls kept at 0°C for 10 d.Scientific Journal Series Paper No. 13842 of the Minnesota Agricultural Experiment Station, St. Paul, Minn