1000 resultados para complex script


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Background:Effective interventions to improve medication adherence are usually complex and expensive.Objective:To assess the impact of a low-cost intervention designed to improve medication adherence and clinical outcomes in post-discharge patients with CVD.Method:A pilot RCT was conducted at a teaching hospital. Intervention was based on the four-item Morisky Medication Adherence Scale (MMAS-4). The primary outcome measure was medication adherence assessed using the eight-item MMAS at baseline, at 1 month post hospital discharge and re-assessed 1 year after hospital discharge. Other outcomes included readmission and mortality rates.Results:61 patients were randomized to intervention (n = 30) and control (n = 31) groups. The mean age of the patients was 61 years (SD 12.73), 52.5% were males, and 57.4% were married or living with a partner. Mean number of prescribed medications per patient was 4.5 (SD 3.3). Medication adherence was correlated to intervention (p = 0.04) and after 1 month, 48.4% of patients in the control group and 83.3% in the intervention group were considered adherent. However, this difference decreased after 1 year, when adherence was 34.8% and 60.9%, respectively. Readmission and mortality rates were related to low adherence in both groups.Conclusion:The intervention based on a validated patient self-report instrument for assessing adherence is a potentially effective method to improve adherent behavior and can be successfully used as a tool to guide adherence counseling in the clinical visit. However, a larger study is required to assess the real impact of intervention on these outcomes.

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Background:Isolated congenital atrioventricular block (CAVB) is a rare condition with multiple clinical outcomes. Ventricular remodeling can occur in approximately 10% of the patients after pacemaker (PM) implantation.Objectives:To assess the functional capacity of children and young adults with isolated CAVB and chronic pacing of the right ventricle (RV) and evaluate its correlation with predictors of ventricular remodeling.Methods:This cross-sectional study used a cohort of patients with isolated CAVB and RV pacing for over a year. The subjects underwent clinical and echocardiographic evaluation. Functional capacity was assessed using the six-minute walk test. Chi-square test, Fisher's exact test, and Pearson correlation coefficient were used, considering a significance level of 5%.Results:A total of 61 individuals were evaluated between March 2010 and December 2013, of which 67.2% were women, aged between 7 and 41 years, who were using PMs for 13.5 ± 6.3 years. The percentage of ventricular pacing was 97.9 ± 4.1%, and the duration of the paced QRS complex was 153.7 ± 19.1 ms. Majority of the subjects (95.1%) were asymptomatic and did not use any medication. The mean distance walked was 546.9 ± 76.2 meters and was strongly correlated with the predicted distance (r = 0.907, p = 0.001) but not with risk factors for ventricular remodeling. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0)Conclusions:The functional capacity of isolated CAVB patients with chronic RV pacing was satisfactory but did not correlate with risk factors for ventricular remodeling.

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Complex Microwave Structures Wake Field Computatation PETRA III Generalized Multipole Technique Antenna Antennen Wakefelder Berechnung

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AbstractThe image of the hospital representing the modern medicine and its diagnostic and therapeutic advances becomes more evident in the face of an aging population and patients with multiple comorbidities requiring highly complex care. However, recent studies have shown a growing number of hospital readmissions within 30 days after discharge. The post-hospital syndrome is a new clinical entity associated with multiple vulnerabilities that contribute to hospital readmissions. During hospitalization, the patient is exposed to different stressors of physical, environmental, and psychosocial natures that trigger pathophysiological and multisystemic responses and increase the risk of complications after hospital discharge. Patients with a cardiac disease have high rates of readmission within 30 days. Therefore, it is important for cardiologists to recognize the post-hospital syndrome since it may impact their daily practice. This review aims at discussing the current scientific evidence regarding predictors and stressors involved in the post-hospital syndrome and the measures that are currently being taken to minimize their effects.

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Magdeburg, Univ., Fak. für Mathematik, Habil.-Schr., 2010

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Abstract Background: Spirituality may influence how patients cope with their illness. Objectives: We assessed whether spirituality may influence adherence to management of outpatients with heart failure. Methods: Cross sectional study enrolling consecutive ambulatory heart failure patients in whom adherence to multidisciplinary treatment was evaluated. Patients were assessed for quality of life, depression, religiosity and spirituality utilizing validated questionnaires. Correlations between adherence and psychosocial variables of interest were obtained. Logistic regression models explored independent predictors of adherence. Results: One hundred and thirty patients (age 60 ± 13 years; 67% male) were interviewed. Adequate adherence score was observed in 38.5% of the patients. Neither depression nor religiosity was correlated to adherence, when assessed separately. Interestingly, spirituality, when assessed by both total score sum (r = 0.26; p = 0.003) and by all specific domains, was positively correlated to adherence. Finally, the combination of spirituality, religiosity and personal beliefs was an independent predictor of adherence when adjusted for demographics, clinical characteristics and psychosocial instruments. Conclusion: Spirituality, religiosity and personal beliefs were the only variables consistently associated with compliance to medication in a cohort of outpatients with heart failure. Our data suggest that adequately addressing these aspects on patient’s care may lead to an improvement in adherence patterns in the complex heart failure management.

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Abstract Background: Right-sided heart failure has high morbidity and mortality, and may be caused by pulmonary arterial hypertension. Fractal dimension is a differentiated and innovative method used in histological evaluations that allows the characterization of irregular and complex structures and the quantification of structural tissue changes. Objective: To assess the use of fractal dimension in cardiomyocytes of rats with monocrotaline-induced pulmonary arterial hypertension, in addition to providing histological and functional analysis. Methods: Male Wistar rats were divided into 2 groups: control (C; n = 8) and monocrotaline-induced pulmonary arterial hypertension (M; n = 8). Five weeks after pulmonary arterial hypertension induction with monocrotaline, echocardiography was performed and the animals were euthanized. The heart was dissected, the ventricles weighed to assess anatomical parameters, and histological slides were prepared and stained with hematoxylin/eosin for fractal dimension analysis, performed using box-counting method. Data normality was tested (Shapiro-Wilk test), and the groups were compared with non-paired Student t test or Mann Whitney test (p < 0.05). Results: Higher fractal dimension values were observed in group M as compared to group C (1.39 ± 0.05 vs. 1.37 ± 0.04; p < 0.05). Echocardiography showed lower pulmonary artery flow velocity, pulmonary acceleration time and ejection time values in group M, suggesting function worsening in those animals. Conclusion: The changes observed confirm pulmonary-arterial-hypertension-induced cardiac dysfunction, and point to fractal dimension as an effective method to evaluate cardiac morphological changes induced by ventricular dysfunction.

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The male of Eneoptera surinamensis (Orthoptera-Eneopteridae) is provided with 9 chromosomes, that is, with 3 pairs of autosomes and 3 sex chromosomes. Spermatogonia. - The autosomes of the spermatogonia are of the same size and U-shaped. One of the sex chromosomes approximately equalling the autosomes in size is telocentric, while the other two are much larger and V-shaped. One of the latter is smaller than the other. The sex chromosomes as showed in Figs. 1 and 2 are designated by X, Yl and Y2, X being the larger V, Yl the smaller one and Y2 the rod-shaped. Primary spermatocytes. - Before the growth period of the spermatocytes all the three sex chromosomes are visible in a state of strong heteropycnosis. X is remarkable in this stage in having two long arms well separated by a wide commissural segment. (Figs. 4, 5 and 6). During the growth period Y2 disappears, while X and Yl remain in a condensed form until metaphase. These may be separated from one another or united in the most varied and irregular manner. (Fig. 7 to 12). In the latter case the segments in contact seem to be always different so that we cannot recognize any homology of parts in the sense os genetics. At diplotene Y2 reappears together with the autosomal tetrads. X and Yl may again be seen as separate or united elements. (Figs. 13 and 14). At later diakinesis and metaphase the three sex chromosomes are always independent from each other, Y2 being typically rod-shaped, X and Yl V-shaped, X being a little larger than Yl. (Fig. 15 to 18). At metaphase the three condensed tetrads go to the equatorial plane, while the sex chromosomes occupy any position at both sides of this plane. In almost all figures which could be perfectly analysed X appeared at one side of the autosomal plate an Yl together with Y2 far apart at the other side. (Figs. 16 and 18). Only a few exception have been found. (Figs. 17 and 19). At anaphase X goes in precession to one pole, Yl and Y2 to the other (Figs. 20 and 21). As it is suggested by the few figures in which a localization of the sex chromosomes different from the normal has been observed, the possibility of other types of segregation of these elements cannot be entirely precluded. But, if this does happen, the resulting gametes should be inviable or give inviable zygotes. Early in anaphase autosomes and sex chromosomes divide longitudinally, being maintained united only by the kinetochore. (Figs. 20 and 21). At metaphase the three sex chromosomes seem to show no special repulsion against each other, X being found in the proximity of Yl or Y2 indifferently. At anaphase, however, the evidences in hand point to a stronger repulsion between X on the one side and both Ys on the other, so that in spite of the mutual repulsion of the latter they finish by going to the same pole. Secondary spermatocytes. - At telophase of the primary spermatocytes all the chromosomes enter into distension without disappearing of view. A nuclear membrane is formed around the chromosomes. All the chromosomes excepting Y2 which has two arms, are four-branched. (Fig. 22). Soon the chromosomes enter again into contraction giving rise to the secondary metaphase plate. Secondary spermatocytes provided as expected with four and five chromosomes are abundantly found. (Figs. 23 and 24). In the former all chromosomes are X-shaped while in the latter there is one which is V-shaped. This is the rod- shaped Y2. In the anaphase of the spermatocytes with four chromosomes all the chromosomes are V-shaped, one of them (X) being much larger than the others. In those with five there is one rod-shaped chromosome (Y2). (Fig. 25), Spermatids. Two classes of spermatids are produced, one with X and other with Yl and Y2. All the autosomes as well as Y2 soon enter into solution, X remaining visible for long time in one class and Yl in the other. (Figs. 26 and 27). Since both are very alike at this stage, one cannot distinguish the two classes of spermatids. Somatic chromosomes in the famale. - In the follicular cells of the ovary 8 chromosomes were found, two of which are much larger than the rest. (Figs. 29 and 30). These are considered as being sex chromosomes. CONCLUSION: Eneoptera surinamensis has a new type of sex-determining mechanism, the male being X Yl Y2 and the female XX. The sex chromosomes segregate without entering into contact at metaphase or forming group. After a review of the other known cases of complex sex chromosome mechanism the author held that Eneoptera is the unique representative of a true determinate segregation of sex chromosomes. Y2 behaving as sex chromosome and as autosome is considered as representing an intermediary state of the evolution of the sex chromosomes.

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In this paper the author describes a very interesting case of union of two homologous chromosomes of the scorpion Tityus bahiensis just by the opposite extremities. The two normal pairs of chromosomes behave as ordinarily, the members of each pair showing at times a slight disturbance in their regular parallelism. The complex chromosome, on the contrary, behaves itself as if it were devoid of kinetochores, that is, it does not orient like normal chromosomes nor reveal any kind of active movement. The fusion of the chromosomes has resulted from terminal breakage at the opposite ends, the correspondig fragments having been found unpaired in a cell in which two pairs of chromosomes were present. Consequently, the compound chromosome, like the normal ones, is provided with a kinetochore at each one of the free ends. Being thus a centric chromosome its behavior, or more exactly, its kinetic inactivity may be compared with that of the monovalents found elsewhere in meioses. It is due o the failure of a partner. The fusion of two homologous chromosomes has transformed them into a new chromosomal unit in whose corresponding parts the ability of pairing was entirely abolished. This result is in full contradiction with the theory of a point-to point attraction between homologous chromosomes attributed to particular power of the genes, since, if genes really exist, being placed in their original loci, they would promote the union side by side of the members of the compound chromosome. If an attraction loci-to-loci should prevail the compound chromosome would be bent as in Fig. 8, C or form a ring similar to the loops observed in the inverted segment of sailvary chromosomes of Drosophila, as represented in the Fig. 8, D and this, in accordance with the order of the loci resulting from an union of corresponding or opposite ends of the fused chromosomes, as indicated in the Fig, 8 A and B. The evidence in hand points to a fusion by non homologous extremities. The expected rings, however, have never been found in metaphase plates. From this fact the author concludes that there is no point-to-point attraction between chromosomes, a conclusion in full agreement with the behavior of Hemipteran chromosomes which, in spite of geing composed of two equivalent halves do not bend in order to adjust the corresponding loci. (Cf. the papers on Hemiptera published by the author in this volume).

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In thee present paper the classical concept of the corpuscular gene is dissected out in order to show the inconsistency of some genetical and cytological explanations based on it. The author begins by asking how do the genes perform their specific functions. Genetists say that colour in plants is sometimes due to the presence in the cytoplam of epidermal cells of an organic complex belonging to the anthocyanins and that this complex is produced by genes. The author then asks how can a gene produce an anthocyanin ? In accordance to Haldane's view the first product of a gene may be a free copy of the gene itself which is abandoned to the nucleus and then to the cytoplasm where it enters into reaction with other gene products. If, thus, the different substances which react in the cell for preparing the characters of the organism are copies of the genes then the chromosome must be very extravagant a thing : chain of the most diverse and heterogeneous substances (the genes) like agglutinins, precipitins, antibodies, hormones, erzyms, coenzyms, proteins, hydrocarbons, acids, bases, salts, water soluble and insoluble substances ! It would be very extrange that so a lot of chemical genes should not react with each other. remaining on the contrary, indefinitely the same in spite of the possibility of approaching and touching due to the stato of extreme distension of the chromosomes mouving within the fluid medium of the resting nucleus. If a given medium becomes acid in virtue of the presence of a free copy of an acid gene, then gene and character must be essentially the same thing and the difference between genotype and phenotype disappears, epigenesis gives up its place to preformation, and genetics goes back to its most remote beginnings. The author discusses the complete lack of arguments in support of the view that genes are corpuscular entities. To show the emharracing situation of the genetist who defends the idea of corpuscular genes, Dobzhansky's (1944) assertions that "Discrete entities like genes may be integrated into systems, the chromosomes, functioning as such. The existence of organs and tissues does not preclude their cellular organization" are discussed. In the opinion of the present writer, affirmations as such abrogate one of the most important characteristics of the genes, that is, their functional independence. Indeed, if the genes are independent, each one being capable of passing through mutational alterations or separating from its neighbours without changing them as Dobzhansky says, then the chromosome, genetically speaking, does not constitute a system. If on the other hand, theh chromosome be really a system it will suffer, as such, the influence of the alteration or suppression of the elements integrating it, and in this case the genes cannot be independent. We have therefore to decide : either the chromosome is. a system and th genes are not independent, or the genes are independent and the chromosome is not a syntem. What cannot surely exist is a system (the chromosome) formed by independent organs (the genes), as Dobzhansky admits. The parallel made by Dobzhansky between chromosomes and tissues seems to the author to be inadequate because we cannot compare heterogeneous things like a chromosome considered as a system made up by different organs (the genes), with a tissue formed, as we know, by the same organs (the cells) represented many times. The writer considers the chromosome as a true system and therefore gives no credit to the genes as independent elements. Genetists explain position effects in the following way : The products elaborated by the genes react with each other or with substances previously formed in the cell by the action of other gene products. Supposing that of two neighbouring genes A and B, the former reacts with a certain substance of the cellular medium (X) giving a product C which will suffer the action, of the latter (B). it follows that if the gene changes its position to a place far apart from A, the product it elaborates will spend more time for entering into contact with the substance C resulting from the action of A upon X, whose concentration is greater in the proximities of A. In this condition another gene produtc may anticipate the product of B in reacting with C, the normal course of reactions being altered from this time up. Let we see how many incongruencies and contradictions exist in such an explanation. Firstly, it has been established by genetists that the reaction due.to gene activities are specific and develop in a definite order, so that, each reaction prepares the medium for the following. Therefore, if the medium C resulting from the action of A upon x is the specific medium for the activity of B, it follows that no other gene, in consequence of its specificity, can work in this medium. It is only after the interference of B, changing the medium, that a new gene may enter into action. Since the genotype has not been modified by the change of the place of the gene, it is evident that the unique result we have to attend is a little delay without seious consequence in the beginning of the reaction of the product of B With its specific substratum C. This delay would be largely compensated by a greater amount of the substance C which the product of B should found already prepared. Moreover, the explanation did not take into account the fact that the genes work in the resting nucleus and that in this stage the chromosomes, very long and thin, form a network plunged into the nuclear sap. in which they are surely not still, changing from cell to cell and In the same cell from time to time, the distance separating any two genes of the same chromosome or of different ones. The idea that the genes may react directly with each other and not by means of their products, would lead to the concept of Goidschmidt and Piza, in accordance to which the chromosomes function as wholes. Really, if a gene B, accustomed to work between A and C (as for instance in the chromosome ABCDEF), passes to function differently only because an inversion has transferred it to the neighbourhood of F (as in AEDOBF), the gene F must equally be changed since we cannot almH that, of two reacting genes, only one is modified The genes E and A will be altered in the same way due to the change of place-of the former. Assuming that any modification in a gene causes a compensatory modification in its neighbour in order to re-establich the equilibrium of the reactions, we conclude that all the genes are modified in consequence of an inversion. The same would happen by mutations. The transformation of B into B' would changeA and C into A' and C respectively. The latter, reacting withD would transform it into D' and soon the whole chromosome would be modified. A localized change would therefore transform a primitive whole T into a new one T', as Piza pretends. The attraction point-to-point by the chromosomes is denied by the nresent writer. Arguments and facts favouring the view that chromosomes attract one another as wholes are presented. A fact which in the opinion of the author compromises sereously the idea of specific attraction gene-to-gene is found inthe behavior of the mutated gene. As we know, in homozygosis, the spme gene is represented twice in corresponding loci of the chromosomes. A mutation in one of them, sometimes so strong that it is capable of changing one sex into the opposite one or even killing the individual, has, notwithstading that, no effect on the previously existing mutual attraction of the corresponding loci. It seems reasonable to conclude that, if the genes A and A attract one another specifically, the attraction will disappear in consequence of the mutation. But, as in heterozygosis the genes continue to attract in the same way as before, it follows that the attraction is not specific and therefore does not be a gene attribute. Since homologous genes attract one another whatever their constitution, how do we understand the lack cf attraction between non homologous genes or between the genes of the same chromosome ? Cnromosome pairing is considered as being submitted to the same principles which govern gametes copulation or conjugation of Ciliata. Modern researches on the mating types of Ciliata offer a solid ground for such an intepretation. Chromosomes conjugate like Ciliata of the same variety, but of different mating types. In a cell there are n different sorts of chromosomes comparable to the varieties of Ciliata of the same species which do not mate. Of each sort there are in the cell only two chromosomes belonging to different mating types (homologous chromosomes). The chromosomes which will conjugate (belonging to the same "variety" but to different "mating types") produce a gamone-like substance that promotes their union, being without action upon the other chromosomes. In this simple way a single substance brings forth the same result that in the case of point-to-point attraction would be reached through the cooperation of as many different substances as the genes present in the chromosome. The chromosomes like the Ciliata, divide many times before they conjugate. (Gonial chromosomes) Like the Ciliata, when they reach maturity, they copulate. (Cyte chromosomes). Again, like the Ciliata which aggregate into clumps before mating, the chrorrasrmes join together in one side of the nucleus before pairing. (.Synizesis). Like the Ciliata which come out from the clumps paired two by two, the chromosomes leave the synizesis knot also in pairs. (Pachytene) The chromosomes, like the Ciliata, begin pairing at any part of their body. After some time the latter adjust their mouths, the former their kinetochores. During conjugation the Ciliata as well as the chromosomes exchange parts. Finally, the ones as the others separate to initiate a new cycle of divisions. It seems to the author that the analogies are to many to be overlooked. When two chemical compounds react with one another, both are transformed and new products appear at the and of the reaction. In the reaction in which the protoplasm takes place, a sharp difference is to be noted. The protoplasm, contrarily to what happens with the chemical substances, does not enter directly into reaction, but by means of products of its physiological activities. More than that while the compounds with Wich it reacts are changed, it preserves indefinitely its constitution. Here is one of the most important differences in the behavior of living and lifeless matter. Genes, accordingly, do not alter their constitution when they enter into reaction. Genetists contradict themselves when they affirm, on the one hand, that genes are entities which maintain indefinitely their chemical composition, and on the other hand, that mutation is a change in the chemica composition of the genes. They are thus conferring to the genes properties of the living and the lifeless substances. The protoplasm, as we know, without changing its composition, can synthesize different kinds of compounds as enzyms, hormones, and the like. A mutation, in the opinion of the writer would then be a new property acquired by the protoplasm without altering its chemical composition. With regard to the activities of the enzyms In the cells, the author writes : Due to the specificity of the enzyms we have that what determines the order in which they will enter into play is the chemical composition of the substances appearing in the protoplasm. Suppose that a nucleoproteln comes in relation to a protoplasm in which the following enzyms are present: a protease which breaks the nucleoproteln into protein and nucleic acid; a polynucleotidase which fragments the nucleic acid into nucleotids; a nucleotidase which decomposes the nucleotids into nucleoids and phosphoric acid; and, finally, a nucleosidase which attacs the nucleosids with production of sugar and purin or pyramidin bases. Now, it is evident that none of the enzyms which act on the nucleic acid and its products can enter into activity before the decomposition of the nucleoproteln by the protease present in the medium takes place. Leikewise, the nucleosidase cannot works without the nucleotidase previously decomposing the nucleotids, neither the latter can act before the entering into activity of the polynucleotidase for liberating the nucleotids. The number of enzyms which may work at a time depends upon the substances present m the protoplasm. The start and the end of enzym activities, the direction of the reactions toward the decomposition or the synthesis of chemical compounds, the duration of the reactions, all are in the dependence respectively o fthe nature of the substances, of the end products being left in, or retired from the medium, and of the amount of material present. The velocity of the reaction is conditioned by different factors as temperature, pH of the medium, and others. Genetists fall again into contradiction when they say that genes act like enzyms, controlling the reactions in the cells. They do not remember that to cintroll a reaction means to mark its beginning, to determine its direction, to regulate its velocity, and to stop it Enzyms, as we have seen, enjoy none of these properties improperly attributed to them. If, therefore, genes work like enzyms, they do not controll reactions, being, on the contrary, controlled by substances and conditions present in the protoplasm. A gene, like en enzym, cannot go into play, in the absence of the substance to which it is specific. Tne genes are considered as having two roles in the organism one preparing the characters attributed to them and other, preparing the medium for the activities of other genes. At the first glance it seems that only the former is specific. But, if we consider that each gene acts only when the appropriated medium is prepared for it, it follows that the medium is as specific to the gene as the gene to the medium. The author concludes from the analysis of the manner in which genes perform their function, that all the genes work at the same time anywhere in the organism, and that every character results from the activities of all the genes. A gene does therefore not await for a given medium because it is always in the appropriated medium. If the substratum in which it opperates changes, its activity changes correspondingly. Genes are permanently at work. It is true that they attend for an adequate medium to develop a certain actvity. But this does not mean that it is resting while the required cellular environment is being prepared. It never rests. While attending for certain conditions, it opperates in the previous enes It passes from medium to medium, from activity to activity, without stopping anywhere. Genetists are acquainted with situations in which the attended results do not appear. To solve these situations they use to make appeal to the interference of other genes (modifiers, suppressors, activators, intensifiers, dilutors, a. s. o.), nothing else doing in this manner than displacing the problem. To make genetcal systems function genetists confer to their hypothetical entities truly miraculous faculties. To affirm as they do w'th so great a simplicity, that a gene produces an anthocyanin, an enzym, a hormone, or the like, is attribute to the gene activities that onlv very complex structures like cells or glands would be capable of producing Genetists try to avoid this difficulty advancing that the gene works in collaboration with all the other genes as well as with the cytoplasm. Of course, such an affirmation merely means that what works at each time is not the gene, but the whole cell. Consequently, if it is the whole cell which is at work in every situation, it follows that the complete set of genes are permanently in activity, their activity changing in accordance with the part of the organism in which they are working. Transplantation experiments carried out between creeper and normal fowl embryos are discussed in order to show that there is ro local gene action, at least in some cases in which genetists use to recognize such an action. The author thinks that the pleiotropism concept should be applied only to the effects and not to the causes. A pleiotropic gene would be one that in a single actuation upon a more primitive structure were capable of producing by means of secondary influences a multiple effect This definition, however, does not preclude localized gene action, only displacing it. But, if genetics goes back to the egg and puts in it the starting point for all events which in course of development finish by producing the visible characters of the organism, this will signify a great progress. From the analysis of the results of the study of the phenocopies the author concludes that agents other than genes being also capaole of determining the same characters as the genes, these entities lose much of their credit as the unique makers of the organism. Insisting about some points already discussed, the author lays once more stress upon the manner in which the genes exercise their activities, emphasizing that the complete set of genes works jointly in collaboration with the other elements of the cell, and that this work changes with development in the different parts of the organism. To defend this point of view the author starts fron the premiss that a nerve cell is different from a muscle cell. Taking this for granted the author continues saying that those cells have been differentiated as systems, that is all their parts have been changed during development. The nucleus of the nerve cell is therefore different from the nucleus of the muscle cell not only in shape, but also in function. Though fundamentally formed by th same parts, these cells differ integrally from one another by the specialization. Without losing anyone of its essenial properties the protoplasm differentiates itself into distinct kinds of cells, as the living beings differentiate into species. The modified cells within the organism are comparable to the modified organisms within the species. A nervo and a muscle cell of the same organism are therefore like two species originated from a common ancestor : integrally distinct. Like the cytoplasm, the nucleus of a nerve cell differs from the one of a muscle cell in all pecularities and accordingly, nerve cell chromosomes are different from muscle cell chromosomes. We cannot understand differentiation of a part only of a cell. The differentiation must be of the whole cell as a system. When a cell in the course of development becomes a nerve cell or a muscle cell , it undoubtedly acquires nerve cell or muscle cell cytoplasm and nucleus respectively. It is not admissible that the cytoplasm has been changed r.lone, the nucleus remaining the same in both kinds of cells. It is therefore legitimate to conclude that nerve ceil ha.s nerve cell chromosomes and muscle cell, muscle cell chromosomes. Consequently, the genes, representing as they do, specific functions of the chromossomes, are different in different sorts of cells. After having discussed the development of the Amphibian egg on the light of modern researches, the author says : We have seen till now that the development of the egg is almost finished and the larva about to become a free-swimming tadepole and, notwithstanding this, the genes have not yet entered with their specific work. If the haed and tail position is determined without the concourse of the genes; if dorso-ventrality and bilaterality of the embryo are not due to specific gene actions; if the unequal division of the blastula cells, the different speed with which the cells multiply in each hemisphere, and the differential repartition of the substances present in the cytoplasm, all this do not depend on genes; if gastrulation, neurulation. division of the embryo body into morphogenetic fields, definitive determination of primordia, and histological differentiation of the organism go on without the specific cooperation of the genes, it is the case of asking to what then the genes serve ? Based on the mechanism of plant galls formation by gall insects and on the manner in which organizers and their products exercise their activities in the developing organism, the author interprets gene action in the following way : The genes alter structures which have been formed without their specific intervention. Working in one substratum whose existence does not depend o nthem, the genes would be capable of modelling in it the particularities which make it characteristic for a given individual. Thus, the tegument of an animal, as a fundamental structure of the organism, is not due to gene action, but the presence or absence of hair, scales, tubercles, spines, the colour or any other particularities of the skin, may be decided by the genes. The organizer decides whether a primordium will be eye or gill. The details of these organs, however, are left to the genetic potentiality of the tissue which received the induction. For instance, Urodele mouth organizer induces Anura presumptive epidermis to develop into mouth. But, this mouth will be farhioned in the Anura manner. Finalizing the author presents his own concept of the genes. The genes are not independent material particles charged with specific activities, but specific functions of the whole chromosome. To say that a given chromosome has n genes means that this chromonome, in different circumstances, may exercise n distinct activities. Thus, under the influence of a leg evocator the chromosome, as whole, develops its "leg" activity, while wbitm the field of influence of an eye evocator it will develop its "eye" activity. Translocations, deficiencies and inversions will transform more or less deeply a whole into another one, This new whole may continue to produce the same activities it had formerly in addition to those wich may have been induced by the grafted fragment, may lose some functions or acquire entirely new properties, that is, properties that none of them had previously The theoretical possibility of the chromosomes acquiring new genetical properties in consequence of an exchange of parts postulated by the present writer has been experimentally confirmed by Dobzhansky, who verified that, when any two Drosophila pseudoobscura II - chromosomes exchange parts, the chossover chromosomes show new "synthetic" genetical effects.

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Having had the opportunity of studying a male of the species Isometrus maculatus De Qeer (Scorplones, Buthidae) the author was able to observe one of the most interesting anomalies hitherto met with in his investigations on Scorpions. This anomaly consisted in the formation by the primary spermatocyte metaphase chromosomes of a complex group of eight elements, and two independent pairs. As it is clear, the octovalent group resulted from tranlocations involving the members of four chromosome pairs. Since aside the compound group two independent bivalents were always present, 12 was estabilished as representing the diploid chromosome number of the individual, what was soon confirmed by the counts in the spermatogonia. This peculiar behavior of the chromosomes of the primary spermatocytes represents the habitual condition in the studied individual, since it was found everywhere in the whole testis. Better than any description, the figures in this, paper show what was observed. Notwithstanding the complications which may occur at anaphase, separation of the chromosomes goes normally, each pole receiving four chromosomes from the group and two from the free bivalents. Secondary spermatocytes are thus provided with six monovalents. Though not found, we may believe in the existence of secondary spermatocytes with more or lesse than six chromosomes, because it seems highly probable that lhe chromosomes of the complex may now and then passe to the wrong pole 'n consequence of an incorrect orientation. Bridge vestiges suggest that chromosomes may sometimes break. The spermatogonia have 12 short chromosomes, which bend to the poles at anaphase. The chromosomes of the present species approach, in shape and behavior, those of Tityus mattogrossensis.

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A natural chromosomal race of Tityus babiensis (Scorpiones Buthidae) is described in the present paper. Five males and seven females received from St. Joaquim, State of S. Paulo, gave the following interesting results: All the spermatogonia of the five males were provided with 9 chromosomes of different sizes. All primary spermatocytes showed at metaphase one independent bivalent of normal shape and a complex group formed by 7 chromosomes which have exchanged parts. Some of the chromosomes associated in the complex group, to Judge by their behavior, were composed of fragments of three different chromosomes, being thus paired with three other members of the compound group. The manner in which all the 7 components of the group have paired with each other showed to be very constant. They gave always origin to a double-cross configuration, the longst branch of which being formed by a long chromosome paired with two components of the group and with a third chromosome that did not belong to the group. The chromosomes of the independent bivalent separate regularly, going to different poles. From the 7 elements of the compound group, 4 go to one pole and 3 to the opposite one. Consequently, secondary spermatocytes with 4 and 5 chromosomes are produced. The females, so far as it can be inferred from the study of the follicular cells of the ovariuterus, have 10 chromosomes. These females are, therefore, considered as being monogametic, that is, as producing eggs with 5 chromosomes. A sex-determining mechanism arose in this manner, the spermatozoa with 5 chromosomes giving origin to females and those with 4 to males. The fact that the sex chromosome is one of the elements taking part in the formation of the group, seems highly interesting to the author. Tetraploid cysts have been occasionally found in the testis. In one individual the chromosomes of the tetraploid primary spermatocytes behaved as expected, forming a group of 14 elements, and two independent pairs or a tetravalent group In another individual, the chromosomes of the tetraploid cells have formed two independent groups of 7, and two independent pairs, as if both chromosomal sets were by their turn entirely independent frcm one another. This fact is certainly not devoid of special interest. The males as well as the females studied in this paper differed in nothing from the typical members of the species. The unique differential character of the new race is found in the umber and behavior of its chromosomes. It is highly remarkable that the occurrences which have transformed the 6 chromosomes normally present in the species into a new set of 9 elements, 7 of which have been profoun- dly altered in their structure, do not show any influence on the morphology of the organism. This fact, together with those found in the salivary-chromosomes races of Drosophila and Sciara. compromises strongly the genetical concept of position effects.

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This paper proves the following theorems on the gamma function: Theorem I The integral ∫O∞ t u e-t dt = Γ ( u + 1 ) , where u, real or complex, is such that R (u) > -1, will not change its value if we substitute z = Q (cos φ + i sen φ) for the real variable t, being jconstant and such that - Π/2 < φ < Π/2 , Theorem II The integral ∫-∞∞ w2u + 1 e -w² dw = Γ ( u + 1 ) , where 2u + 1 is supposed to be a non negative even integer, will not change its value if we substitute z = w + fi, f being a real constant, for the real variable w. The proof of both theorems is obtained by means of the well known Cauchy theorem on contour integrals on the complex plane, as suggested by CRAMÉR (1, p. 126) and LEVY (3, p. 178).

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The determination of total nitrogen, phosphorus, and potassium in plant material can be carried out in a common extract prepared with sulphuric acid and 30 per cent hydrogen peroxide. Nitrogen is estimated by direct nesslerization of a suitable aliquot (1-5 ml of the 50 ml extract made out of 250 mg of dried material); in order to avoid excessive acidity, 10 ml of Nessler's reagent should be employed. An aliquot of 1-5 ml suffices for the colorimetric determination of phosphorus by the molybdenum method; to reduce the phosphomolybdate complex 2 ml of a 2% SnC12 soln are necessary. Potassium is determined by the cobaltinitrite method after elimination of ammonium salts with the aid of aqua-regia.