scholarly journals Razones y maravedís: una mirada crítica a los negocios del ferrocarril en España (1844-1943)

2018 ◽  
pp. 522
Author(s):  
Domingo Cuéllar
Keyword(s):  
Economic History ◽  
Complex Analysis ◽  
Conflicts Of Interest ◽  
Regulatory State ◽  
Private Companies ◽  
Long Term Study ◽  
State Financing ◽  
La Red ◽  
Made In

Resumen: El negocio de los ferrocarriles en España en la etapa del sistema de concesiones a compañías privadas abarcó un largo periodo que se aproximó al siglo. La primera línea puesta en explotación lo hizo en 1848 y la nacionalización de toda la red de vía ancha se decretó en 1941. El estudio en el largo plazo del desarrollo de esas empresas y su relación con el Estado regulador del sistema tiene tres periodos claves bien diferenciados, aunque muy desiguales en su duración: la concesión, la explotación y el rescate.En cada una de esas etapas se tejieron relaciones de complejo análisis y se presentaron escenarios con evidentes conflictos de intereses entre sus protagonistas, se dieron desembolsos no siempre justificados de los caudales públicos, o se promulgaron normas que no ayudaron a un funcionamiento equilibrado del sistema. El ferrocarril siempre ha estado en el punto de mira, lo que nos obliga a hacer un análisis crítico de su historia.Palabras clave: Historia económica, Ferrocarriles, Empresas, Estado, Financiación Historia contemporánea de España, Historia de Cataluña.Abstract: The business of the railways in Spain in the stage of the system of concessions to private companies covered a long period that approached the century. The first line put into operation was made in 1848 and the nationalization of the entire wide-track network was enacted in 1941. The long-term study of the development of these companies and their relationship with the regulatory state of the system has three key periods differentiated, although very unequal in their duration: the concession, the exploitation and the rescue.In each of these stages, it’s spun relationships with complex analysis and it’s made scenarios with obvious conflicts of interest between their protagonists, outlays not always justified from public flows, or rules were promulgated that did not help a balanced functioning of the system. The railway has always been in the spotlight, which forces us to make a critical analysis of its history.Keywords: Economic History, Railways, Companies, State, Financing.

scholarly journals Stroke Prevention in Atrial Fibrillation: Where are We Now?

2012 ◽  
Vol 6 ◽  
pp. CMC.S8976 ◽  
Author(s):  
Yousif Ahmad ◽  
Gregory Y.H. Lip
Keyword(s):  
Atrial Fibrillation ◽  
Stroke Prevention ◽  
Management Strategies ◽  
Bleeding Risk ◽  
Long Term Study ◽  
Risk Patients ◽  
First Time ◽  
Major Progress ◽  
Made In

Atrial fibrillation is the commonest arrhythmia worldwide and is a growing problem. AF is responsible for 25% of all strokes, and these patients suffer greater mortality and disability. Warfarin has traditionally been the only successful therapy for stroke prevention, but its limitations have resulted in underutilisation. Major progress has been made in AF research, leading to improved management strategies. Better risk stratification permits identification of truly low-risk patients who do not require anticoagulation and we are able to simplify ourevaluation of a patient's bleeding risk. The advent of novel anticoagulants means warfarin is no longer the only choice for stroke prophylaxis. These drugs circumvent many of warfarin's inconveniences, but only long-term study and use will conclusively demonstrate how they compare to warfarin. The landscape of stroke prevention in AF has changed with effective alternatives to warfarin available for the first time in 60 years—but each new option brings new considerations.

scholarly journals Effects of Environmental Variables on Some Physiological Responses of Microtus Montanus Under Natural Conditions

1978 ◽  
Vol 2 ◽  
pp. 45-47
Author(s):  
Aelita Pinter
Keyword(s):  
Population Density ◽  
Environmental Variables ◽  
Reproductive Activity ◽  
Natural Conditions ◽  
Microtus Montanus ◽  
Long Term Study ◽  
Microtine Rodents ◽  
Different Seasons ◽  
Made In

Several microtine species exhibit multiannual fluctuations in population density. These fluctuations have been described as occurring with sufficient regularity to be called "cycles". This phenomenon has been known since antiquity. However, despite the extensive work that has dealt with this problem, the facts underlying these fluctations remain largely unknown. Preliminary field observations of populations of montane voles (Microtus montanus ) in Grand Teton National Park were made in 1961, and from 1966 through 1968 (Pinter, unpublished observations). At about the same time laboratory studies began to reveal the remarkable sensitivity of the reproductive system of these rodents to environmental variables . However, little was known to what degree environmental factors and reproductive responses of these rodents contributed to the cyclicity of their population density. Consequently, in 1969 a long term study was initiated. The purpose of the study was essentially fourfold. First, to characterize the environmental variables that might affect Microtus in different seasons of the year. Second, to record the growth, maturation, and reproductive activity of Microtus montanus under natural conditions. Third, to determine the maturational as well as the seasonal pelage changes of these rodents. Fourth, the data resulting from the execution of the first three objectives would be correlated in an attempt to determine the causes underlying the multiannual fluctations in population density of these microtine rodents.

scholarly journals RESEARCHES ON MONITORING AND EARLY WARNING OF BROWN ROT MONILIA LAXA ATTACK ON SOME VARIETIES OF CHERRY AND PLUM

2020 ◽  
Vol 36 ◽  
pp. 33-44
Author(s):  
Florin Cristian Marin ◽  
Mirela Calinescu ◽  
Mihaela Sumedrea ◽  
Emil Chitu
Keyword(s):  
Early Warning ◽  
Brown Rot ◽  
Fruit Species ◽  
Long Term Study ◽  
Weather Stations ◽  
Plum Varieties ◽  
Disease Attack ◽  
Monitoring And Early Warning ◽  
Made In

Brown rot caused by Monilia laxa (Aderh. & Ruhland, Honey) is one of the most damaging fungal disease for stone fruit species, in all European countries and in Romania as well. A great deal effort is done to study its biology and ecology, for disease monitoring and containment. This paper presents the result obtained at RIFG Pitesti Romania during 2018-2020 in monitoring and early warning of the disease attack, using two different weather stations and forecast modules made in Europe and USA. A correlation was found (R2=0.0146, r=0.1208, n=585), which proves that the microclimate was favorable for stone fruits brown rot infections, for varieties evaluation and classification and to supply data to develop new early warning tools as well. The results obtained with the two forecast systems makes possible the early warning on the attack risk of brown rot, both cherry and plum orchards. In the same period 26 cherry and 22 plum varieties were studied regarding their behavior to the pathogen natural infections. Among the Romanian varieties the ones with the lowest damages degree were: 'George', 'Clasic', 'Daria', 'Negre de Bistriţa', 'Roşii de Bistriţa', 'Rubin', 'Severin' and 'Uriaşe de Bistriţa' (DD%=0.13-0.14) on cherry and 'Pescaruş' 'Record', 'Gras ameliorat', 'Romanţa', 'Roman, 'Ialomiţa' and 'Dâmboviţa' (DD%=0.03-0.14) on plum. Under long term study, the most sensitives to brown rot attack were 'Lapins' cherry variety (DD%=3.93) as well as 'Stanley' Centenar and 'd’Agen' plum varieties (DD%=4.68-4.72), which can be used as 'indicators', in order to triggers the phytoprotection programs.

scholarly journals Adaptation of larch (Larix decidua) of Polish provenances under mountainous conditions of Beskid Sądecki (southern Poland)

2012 ◽  
Vol 50 (No. 12) ◽  
pp. 559-565 ◽  
Author(s):  
M. Kulej
Keyword(s):  
Extreme Values ◽  
Early Stage ◽  
Tree Height ◽  
Test Site ◽  
Site Conditions ◽  
Term Study ◽  
Long Term Study ◽  
Effective Selection ◽  
Made In

A long-term study carried out within the 1967 All-Poland Larch Provenance Experiment investigated genetic variation in 20 Polish provenances of larch growing under the site conditions of the Beskid Sądecki Mts. (at a test site in Krynica). The study was based on the measurements of tree height made in individual larch populations during 1969–1999, i.e. when trees were 5, 8, 11, 15, 20, 25, 30 and 35 years old. The results showed a considerable adaptation stability of the provenances tested at the Krynica site. This stability, however, tended to decrease with increasing mean height of trees. An estimation of the effect of the “genotype (provenance) × years of observation (age)” interaction revealed a high stability of height growth in larch populations having extreme values of this trait. As follows from the study, it is possible, especially in the case of the latter group of provenances, to carry out effective selection in the early stage of tree growth, thus ensuring a permanent genetic gain.

scholarly journals Dioecy and the evolution of sex ratios in ants

2009 ◽  
Vol 276 (1664) ◽  
pp. 2125-2132 ◽  
Author(s):  
Diane C. Wiernasz ◽  
Blaine J. Cole
Keyword(s):  
Sex Ratio ◽  
Social Insects ◽  
Conflicts Of Interest ◽  
Evolutionarily Stable Strategy ◽  
Sex Ratios ◽  
Harvester Ants ◽  
Long Term Study ◽  
Comprehensive Framework ◽  
Evolution Of Dioecy

Split sex ratios, when some colonies produce only male and others only female reproductives, is a common feature of social insects, especially ants. The most widely accepted explanation for split sex ratios was proposed by Boomsma and Grafen, and is driven by conflicts of interest among colonies that vary in relatedness. The predictions of the Boomsma–Grafen model have been confirmed in many cases, but contradicted in several others. We adapt a model for the evolution of dioecy in plants to make predictions about the evolution of split sex ratios in social insects. Reproductive specialization results from the instability of the evolutionarily stable strategy (ESS) sex ratio, and is independent of variation in relatedness. We test predictions of the model with data from a long-term study of harvester ants, and show that it correctly predicts the intermediate sex ratios we observe in our study species. The dioecy model provides a comprehensive framework for sex allocation that is based on the pay-offs to the colony via production of males and females, and is independent of the genetic variation among colonies. However, in populations where the conditions for the Boomsma–Grafen model hold, kin selection will still lead to an association between sex ratio and relatedness.

Repeated Botox Injections Deemed Safe in Long-Term Study

2005 ◽  
Vol 36 (1) ◽  
pp. 2
Author(s):  
BETSY BATES
Keyword(s):  
Term Study ◽  
Long Term Study

Long-Term Study Proves Permanent Filler Safety

2010 ◽  
Vol 41 (4) ◽  
pp. 23
Author(s):  
BRUCE JANCIN
Keyword(s):  
Term Study ◽  
Long Term Study ◽  
Permanent Filler

Quinapril for Sclerosis Failed in Long-Term Study

2007 ◽  
Vol 38 (6) ◽  
pp. 14
Author(s):  
DAMIAN MCNAMARA
Keyword(s):  
Term Study ◽  
Long Term Study
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