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El artículo presenta noticias que tratan de la economía latinoamericana. Se informa sobre una comisión colombo-ecuatoriana que estudia las posibilidades de integración de las zonas fronterizas de ambos países. Se anuncia que Chile es uno de los grandes exportadores de papel. Se habla de un remanente de 300.000 toneladas de trigo que tiene Uruguay para exportación.

When all the fire companies in a region are engaged in fighting fires, protection against a future fire is considerably reduced. It is standard practice in many urban fire departments to protect the exposed region by relocating outside fire companies temporarily to some of the vacant houses. In New York City, situations requiring such relocations arise ten times a day on the average. The Fire Department of the City of New York (FDNY) currently makes its relocations according to a system of preplanned moves. This system was designed at a time when alarm rates were low and is based on the assumption that only one fire is in progress at a time. Because of the high alarm rates currently being experienced in parts of New York City, this assumption is no longer valid, and the preplanned relocation system breaks down at the times when it is needed most. This paper describes a computer-based method for determining relocations that overcomes the deficiencies of the existing method by utilizing the computer's ability to (1) store up-to-date information about the status of all fires in progress and the location and activity of all fire companies, (2) generate and compare many alternative relocation plans quickly. The method, which will become part of the FDNY's real-time Management Information and Control System (MICS), is designed to be fast and to require little computer memory. After giving some background of the problem and the objectives of relocation, we give the problem a mathematical programming formulation and then describe the heuristic algorithm to be used for generating relocations in the MICS. The remainder of the paper is devoted to a discussion of an example illustrating how the algorithm works, a rigorous test of the algorithm using a computer simulation model of Fire-Department operations, and a description of the current use of... [ABSTRACT FROM AUTHOR]

A paper chromatography method for qualitative analysis of the carbohydrates (in 85% ethanol soluble fraction) of Taraxacum Koksaghyz is described. Different parts of the plant have been analyzed. In the fresh roots the following carbohydrates were found: levulose, saccharose, probably raffinose, levulines and four other spots of low R values - all of them ketose compounds. Roots dryed during a period of 48 hours at 55° C before analysis have the same chromatogram. In the fresh leaves only levulose, glucose and saccharose appeared. In the dry leaves besides these carbohydrates three more spots of low R values were found: all of them ketose compounds. Before, during and after the flowering period, the floral stems contained levulose, glucose and saccharose. The buds contain levulose, glucose, saccharose and four other non-identified carbohydrates, all of them ketose compounds. [ABSTRACT FROM AUTHOR]

The London School of Economics have, since 1959, studied the jobs of supervisors in a number of plants to demonstrate their range and variety and the relation of supervisory systems to technology. A previous article (see below) on the first part of the research argued that there was no straightforward relationship between the two, but that organizational and human factors could also greatly determine supervisory jobs. This paper describes the last part of the research which was devoted to a far deeper and more detailed analysis of supervisory jobs in one large firm in an attempt to find more concrete evidence of different influences on supervisory jobs. The results show that the nature of the product, the technical situation, the factory organization, the supervisory training programme and the supervisor's personality all affected both his behaviour and the demands made on him. A supervisor was seen to be reacting to a continuous succession of pressures, some of which ran counter to others. The relative weighting of these against each other, as well as the supervisor's personality, affected the way in which he behaved as well as the subsequent demands made on his job. [ABSTRACT FROM AUTHOR]

Operations-research workers have not met with much success in being accepted as integral members of regional-health-planning teams, owing in part to a lack of understanding by health planners of the skills the operations researcher has to offer and in part the analyst's inability to demonstrate that he can close the gap between theoretical modeling and the implementation of his results. This paper explores the growth of regional health planning in the United States and highlights its important problem areas. The literature of operations-research applications to health planning is reviewed critically with respect to the feasibility of models and the appropriateness of assumptions. Specific problems with the types of studies currently in the literature are identified and recommendations are made for improved coordination between operations-research workers and health planners. [ABSTRACT FROM AUTHOR]

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although the existence of Nocardia asteroides as a human pathogen in Mexico has been known for several years, up to now there are only few reports in our country concerning the isolation of this microorganism both as a saprophyte as well as human or animal pathogen. This fact is more interesting when compared with the high incidence of N. brasiliensis, causal agent of actinomycotic mycetoma, the most frequently observed deep mycosis in Mexico. In this paper, the isolation of eigth strains of N. asteroides from clinical specimens is reported. Five strains were isolated from sputa, one from a fistulous lesion of the scrotum, one from a brain abscess and one more from a foot mycetoma. One of the strains isolated from sputum was in a case of pulmonary nocardiasis; another of these strains was isolated from a patient with coexistent pulmonary tuberculosis and nocardiasis. With the last three strains isolated from sputa, it was not possible to establish any correlation between the isolations and the clinical and radiological findings of the patients; two of the patients had pulmonary tuberculosis and the isolation of N. asteroides was achieved only in one occasion in each case, with scant growth, and observed in routine cultures made for tubercle bacilli. The last strain was isolated from the sputum of a patient with chronic bronchitis. Some comments are made to the possibility that these three last isolations merely represent a saprophytic phase of the fungus. Some clinical and other features are discussed concerning the other three cases of scrotal fistula, brain abscess and mycetoma produced by N. asteroides. [ABSTRACT FROM AUTHOR]

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Neurochirurgica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper the author gives the state probabilities of the following queue model. The arrival and departure precess are at random with λ-mean arrival and μ=mean servicing time in a single channel. The number of channels is in this model a random number depending upon the length of the queue; when the number of waiting units is M and it arrives another unit, the number of channels is increased in one, and this channel services the first unit in queue; when a channel is free and none unit being in queue, this channel es cancelled. Only in the case of the last channel this should be open. So we have the length of the queue is never greater than M. The notation used in the paper is: r=number of units in queue. s=number of channels (of number of elements being serviced). $$\rho = \frac{\lambda }{\mu }$$ P( r,s;t)=Probability of the state ( r, s) on time t. p(r s)=Probability of the state ( r, s) in the steady state of the model. With this notation, we have This model includes as particular cases the model of a single channel, equivale to M-→∞ and the model of infinite channels, equivalent to M=0. [ABSTRACT FROM AUTHOR]

The author define the Median-Regression curve of a bidimensional distribution f(x, y) as the locus y=g(x) of the median of conditional distribution f(y/x). The general propieties of this Median Regresión are given in numbers 1.1 to 1.6 spanish text. As g(x) is not easy to obtain the author introduce, like minimum mean square regression, the minimuni mean regression, as a regression curve that minimize the mean deviation instead of mean square deviation; first the linear mean regression, and further the polinimial mean regression, that ones have some propietioes of regression curve y=g(x). In the empirical distributions the calculus of mean regression involve to find the minimum of a linear expression, with the variables constrained to some inequalities, as in the linear programming, the author discuss some espacial points of this linear programing problem in the third part of the paper. [ABSTRACT FROM AUTHOR]

In order to apply the Hitchcock transportation problem to practical cases, it is very helpful to have a method as simple and brief as possible. The author considers a special case of application of this problem to railways, that of the distribution of empty cars. He recalls how this problem is solved by Dantzig's simplex method and he shows the specially simple values of the coefficients appearing in this case in the simplex tableaus. The great simplification which results makes possible the application of an abbreviated method contained in works of Dantzig and Ricossa. In this paper, (following the conventional terminology and notation for this question) there is given a demonstration of the method based on the arrangement in a tableau of the values of the non-zero solutions λ of the requirement equations system of the problem. So that a group of m+n−1 λ′ will correspond to a basic group vectors P of coefficients of the system, it is necessary for the λ′ to occupy such positions that a chess castle's closed run can not be performed over them. The necessary theory is given to demonstrate this result and consequences are drawn for the selection of an initial basis in the basis changing processus. There is shown how to follow the subsequent calculus by this method, very easily and quickly, until the arrival at the optimal solution or solutions. Finally, the manner of dealing with degeneracy is indicated. [ABSTRACT FROM AUTHOR]

A general survey of non central distribution is given, beginning with well known definitions and expressions of the non central Student's distribution of which different alternatives are presented, for example in terms of the moments of a truncated normal distribution, and followed by the generalised n. c. t distribution. The explicit formulae of its moments and coefficients of skewness and kurtosis are derived, as well as approximations of the same for large values of n (number of degrees of freedom). The above obtained expressions being comparatively difficult to handle, a transformation to normalise the non central t distribution is found, and the general form of the corresponding approximate moments and coefficients, summarised in two main alternatives, one for γ=0, and the other for γ=0. Some special cases are then discussed with detail, and examples of possible applications are widely exposed. Other non central distributions are briefly considered, based on the distribution of semirange, studentised range and analogues of n.c.t, and finally the generalised T distribution, which opened the way for new lines of research and which will be the subject of a subsequent paper. [ABSTRACT FROM AUTHOR]

Copyright of Microchimica Acta is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin Géodésique N.S. is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper gives a set-covering-problem formulation for determining locations for two types of ladder trucks used by the New York City Fire Department. It shows that the formulation can accommodate several different realistic restrictions on the solutions. [ABSTRACT FROM AUTHOR]

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper deals with the yeast Debaryomyces artagaveytiae Bat., J. Silveira & Coelho n. sp. found in woman genital secretion. This fungus is characterised by its biochemical ability to grow in sugar media having glucose, galactose, saccharose and maltose but it does not fermentate these sugars, nor maltose. The mycelium is lacking but through an isogamic conjugation asci are developed, containing from 1 to 4 globose ascospores. The infected woman has been treated successfully with colpomicin. [ABSTRACT FROM AUTHOR]

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Several approximations to the binomial distribution were compared in 1956 by Raft [9], including the normal, arcsine, normal Gram-Charlier, Camp-Paulson, Poisson, and Poisson Gram-Charlier approximations. The closeness of these approximations is judged by the maximal error which can arise in evaluating any sum of consecutive binomial terms. Borges [3] investigated a general class of approximations (which includes some of the above) and showed that a certain beta-transformation of a binomially distributed variable is the unique member of this class which is approximately normal with error 0(l/n). In 1963, Bol'shev [2] gave two new Poisson-type approximations. In this paper, some of Raft's tables are extended and tables for the error of these newer approximations are added. As a consequence of the numerical results obtained, the Poisson Gram-Charlier approximation is recommended for small values of p while the Camp-Paulson and Borges' approximations should generally be preferred for large p. [ABSTRACT FROM AUTHOR]

Data editing by a computer program can be regarded as a form of statistical quality control. In that perspective, costs and benefits of alternative programs can be compared to one another and, of course, to no control plan at all. This paper outlines one approach to cost-benefit comparison and utilizes a realistic example to suggest that computerized data editing is generally superior to clerical editing. It also warns against edit programs which provide for record rejections and off-line review. Most importantly, it urges that a systematic comparison of costs can assist significantly in edit planning. [ABSTRACT FROM AUTHOR]

The Society's Publications Committee and Council have been concerned for some time with need for current bibliographical and abstracting services in operations research This concern led several years ago to the arrangement with the Operations Research Group at Case Institute of Technology under which the Society shared with Case Institute the support for the preparation of a bibliography of titles covering the literature through 1956. The Society then secured support from the Office of Scientific Information of the National Science Foundation for the continuation of this work, with the following results The earlier partial listing for 1957 was completed by the publication by Case Institute in 1959 of "A Comprehensive Bibliography on Operations Research 1957," prepared by the same group, this listing, together with a complete listing for 1958 and extensive special bibliographies prepared also by this group, will be published in a single volume by John Wiley and Sons Inc. in 1961. In the meantime, scholar James H. Batchelor, working independently and entirely within his own resources, was preparing an annotated bibliography that included abstracts for all items except those of minor importance and covered the literature through 1957.

In this paper a way to determinate the value of a finite game is shown making a secuence of matrices with the values of the games determinate by submatrices of the matrix of the game and looking for saddle point in this matrices. [ABSTRACT FROM AUTHOR]

This paper deals with contingency tables n by n in conexion with the case of quantitative observations of random variable arranged in n groups according to n different caracteristics. The subjet is to give a general method to test either the independence of the n caracteristics, either the independence of any sugroup of them. The method is a generalization of the two caracteristics case as stated in Cramer's «Mathematical Methods of Sstatistics». [ABSTRACT FROM AUTHOR]

It is presented in this paper a definition of the equivalence of two rectangular games. It is not compared every value M( x, y) of the payoff function of one of the games with any value M′( x′, y′) of the payoff function of the other game, and when two values are compared they are not necessarily equal. Also the ε-equivalence for two games indicating some properties is defined. [ABSTRACT FROM AUTHOR]

This paper is concerned with tests of distribution free methods in sequential form. One of the most outstanding features of this methods is the broad field of application, we don't need almost any assumption about the distribution function of the random variable that we study. Unfortunately this distribution free methods need a large sample size to get the neccessary accuracy, so the usefulness of sequential methods that have great savings in average sample size. The distribution free test in sequential form has two very important proprieties, broad field of application and a small average sample size. In the first chapter the author give a test S for the median of any distribution, that, in the case of normal distribution has one relative efficiency of 60% againts Wald sequential test, and about 120% against current most powerful test. So we can use this test S instead of the most powerful test with advantage in sample size and in numerical calculus, because the test S is very simple. In the second chapter, the previous tests S is adapted to 'two sample problem', in first time with alternative hypothesis of differences in location, and then generalized to any alternative. With normal distribution and alternative hypothesis of differences in location the test presented by the author is most powerful and smaller in sample size than other usual tests, Wilcoxon, Wald and Wolfowitz, Epstein, Tsao. In the chapter three the author study the tests of randomness in a similar way. [ABSTRACT FROM AUTHOR]

In the planning of a building we find the following situation We have several dependences with the entrance in the same corridor, and this corridor has one door only to street; we know also the proportion of people wich go out from dependence i to extreme A or extreme B (see figure in Spanish version). The question is: In what place we must put the door P to became minimun the total walking for the people going out. The author in this paper give the answer of this question and in the most general case with densities functions instead of proportions. [ABSTRACT FROM AUTHOR]

This paper concern with some questions of independence of random variables. In § 2 we give some definitions and a generalization of Bernstein's example, that show that n random variables may be independents by subsets, but the total set are not independt (§ 3), and also this fact holds in continue variables. In § 6 we give a measure of independence in two and n dimensions (§ § 1, 8) and on use that measure with the Normal distribution (§ § 9, 10, 11) and others distributions (§ § 12, 13). [ABSTRACT FROM AUTHOR]

Alfred Marshall, the venerable dean of English economists, forms a bond between the later nineteenth and the early twentieth century economics, and by his remarkable talent for eclecticism probably embodies and exemplifies better than any one else the more generally prevailing uncritical opinion among English and American economists. There is, indeed, a thoroughgoing inconsistency in Marshall's views as to the central aim of economics, On the one hand he would aim to be a welfare economist. He aspires to make economics a study of real human welfare. But Marshall has also another aspiration, which is constantly tempting him to think and speak as a price economists rather than as a welfare economist. Thus he is led to abandon welfare as the center of economic study and to make money "the center around which economic scene clusters" and to use it as the one convenient means of measuring human motive on a large scale." He finds other difficulties when he attempts to make price the measure of motives as between men of different incomes ; equal sums of money are sought as general purchasing power by different persons for the most diverse motives "high as well as low, spiritual as well as material."

In this third paper dealing with the algae of Brazil, four Chlorophycophyta and six Chrysophycophyta are described. These organism were found in the so called "Sete Lagoas" Lake-District, State of Minas Gerais. They are: Granulochloris maxima nov. sp., Pseudoquadrigula lagoensis nov. gen., nov. sp., Oedogonium spirostriatum, Pseudochaete crassisetum (Chlorophvceae), Phalansterium digitatum (Chrysophyceae), Tetraedriella polychloris, T. acuta, Goniochloris gigas, Peroniella minuta y Pseudostaurastrum enorme (Xanthophyceae). Except Oedogonium, all these genera are mentioned for the first time for Brazil and also for South America. [ABSTRACT FROM AUTHOR]

This paper deals with a taxonomic study of Cyanophyta epiphytic on submerged plants in the following ponds: Chascomús, El Burro, Yalea and Vitel. Keys are given for the identification of the 3 orders, 5 families, 11 enera and 24 species found. The taxa are described and the species illustrated. Eigth species are described for the first time for Argentina. [ABSTRACT FROM AUTHOR]

In the first part of this paper, the author gives basic information on the physiography, climate and vegetation of the studied area, which is located in the northwestern corner of Argentina and covers the provinces of Jujuy, Salta, Catamarca, Tucumán and partially, Santiago del Estero and La Rioja. Also, in that general part, comments are made on the level of the local knowledge of the Pteridophytes. In the subsequent chapters, the author offers a key of families and the revision of Lycopodiaceas, Selagnellaceae, Equisetaceae, Psilotaceae, Ophioglossaceae, Schizaeaceae, Hymenophyllaceae, Cyatheaceae, Dennstaedtiaceae and Adianlaceae (according to Alston's classfication of the leptosporangiate ferns), with a total of 25 genera and 77 species. Under each taxon, the synonymy, types, relationships, cited specimens, distribution patterns and ecological information are given. Three new species are described: Hymenophyllum (Sphaerocionium) capurroi, Cheilanthes volcanensis and Pleris famatinensis and the following combinations are proposed: Adiantum thalictroides var. hirsutum (Hook & Grev.) and Pleris inermis (Rosenst.). Maps, graphs and illustrations of the new taxa are also given. [ABSTRACT FROM AUTHOR]

In the present paper, the fourth of the series which started with a study of the sporophyte of Salvinia oblongifolia, the author reports some data on the following aspects of S. rotundifolia: anatomy of the rhizome and submerged organ. Comparative data on its related species, S. herzogii, are given. [ABSTRACT FROM AUTHOR]

In the present paper, the author describes a new species of Salvinia, S. herzogii, on Argentine material from Lower Paraná River. It is probable that all specimens of this country determined S. auriculata Aublet, belong to this new species. A key for identification of S. herzogii and related species according to the leaf characters and configuration of the submerged organs is given. [ABSTRACT FROM AUTHOR]

Thirty species of Inoperculate Discomycetes are described herein from the Nahuel Huapí National Park (Argentina), distributed among thirteen genera belonging to the following families: Hyaloscyphaceae, Dermataceae, Sclerotiniaceae y Helotiaceae. Three of them, namely, Calloria, Sphagnicola and Phaeohelotium are recorded for the first time for Argentina. Of the thirty species found, fifteen are new records for this country. The following new combinations are proposed: Cyathicula chlorosplenioides (Speg.) Gamundí (basinym: Helotium chlorosplenioides Speg.); Rutstroemia megalospora (Speg.) Gam. (bas.: Helotium megalosporum Speg.) y Rutstroemia microsperma (Speg.) Gamundí (bas.: Helotium microspermum Speg.). The paper contains a critical study of type material from Spegazzini's herbarium, and the description of a new species of the same general area: Phaeohelotium castaneum. [ABSTRACT FROM AUTHOR]

In this short paper, the author reports the presence of Notholaena sulphurea (Cav.) J. Sm. in NW and W Argentina (Jujuy and La Rioja Provinces). A key for the Argentine species of that genus, is also given. [ABSTRACT FROM AUTHOR]

This article focuses on mathematical programming models for capital budgeting. In section one a generalized deterministic mathematical programming model for capital budgeting is provided. Section two demonstrates how these past models are closely related to this model. In the third section uncertainty is discussed through the use of probabilistic concepts and through the utilization of chance-constrained programming. The authors hope to present a comprehensive analysis of the features of programming models for capital budgeting.

Se presentan noticias que tratan de la economía internacional. El Fondo Especial de la Organización de las Naciones Unidas tropezaba con una aguda escasez de recursos financieros. La economía de Europa Occidental entraba en una fase de auge. Se habla del consumo mundial de papel y sus derivados.