Investigation of the rigidity and sensitivity dependence of neutron monitors for cosmic ray modulation using algorithm-selected Forbush decreases

2020 ◽  
Vol 493 (2) ◽  
pp. 1948-1959 ◽  
Author(s):  
O Okike ◽  
O C Nwuzor
Keyword(s):  
Cosmic Ray ◽  
Neutron Monitors ◽  
Event Selection ◽  
Forbush Decreases ◽  
The North ◽  
Cosmic Ray Modulation ◽  
Automated Method ◽  
Significant Difference ◽  
Correct Calculation ◽  
Minimum Number

ABSTRACT We emphasize the need for a careful and rigorous timing of Forbush decreases (FDs) as well as a correct calculation of FD magnitudes in studies related to cosmic ray (CR) modulation. We have employed Fourier and R-based algorithms for FD event selection, timing and magnitude estimation. The large number of Forbush events that have been identified were employed in correlation and regression analyses to investigate the rigidity and sensitivity dependence of neutron monitors (NMs). It was found that there is a significant difference between the number of FDs identified manually and those selected by the automated method. While the minimum number (238) of FDs occurred at Irkutsk NM, the Novosibirsk CR station observed the largest number (386) of Forbush events. However, within the north high-latitude band (39°N ≤ latitude ≤ 90°N), only 29 FDs have been simultaneously identified using the data from some NMs in the region, including Irkutsk and Novosibirsk. The result obtained using a large number of FDs differs significantly from those employing manual identification of Forbush events. We conclude, among other things, that the automation of FD event selection is essential for understanding the dependence of CR modulation on NM rigidity and altitude, as well as on the contribution from terrestrial modulation agents.

scholarly journals Variations of Interplanetary Parameters and Cosmic-Ray Intensities

1980 ◽  
Vol 91 ◽  
pp. 393-398
Author(s):  
A. Geranios
Keyword(s):  
Solar Flare ◽  
Recovery Time ◽  
Propagation Speed ◽  
Cosmic Ray ◽  
Interplanetary Shocks ◽  
Fast Solar Wind ◽  
Neutron Monitors ◽  
Cosmic Ray Intensity ◽  
Cosmic Ray Modulation ◽  
Modulation Region

Observations of cosmic ray intensity depressions by earth bound neutron monitors and measurements of interplanetary parameter's variations aboard geocentric satellites in the period January 1972-July 1974 are analysed and grouped according to their correlation among them. From this analysis of about 30 cases it came out that the majority of the depressions correlates with the average propagation speed of interplanetary shocks as well as with the amplitude of the interplanetary magnetic field after the eruption of a solar flare. About one fourth of the events correlates with corotating fast solar wind streams. As the recovery time of the shock-related depressions depends strongly on the heliographic longitude of the causitive solar flare, it seems that the cosmic ray modulation region has a corotative-like feature.

scholarly journals Estimation of the state of the cosmic ray flux based on neural networks

2020 ◽  
Vol 196 ◽  
pp. 01007
Author(s):  
Bogdana Mandrikova ◽  
Alexei Dmitriev
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
A Priori ◽  
Cosmic Ray ◽  
The State ◽  
Neutron Monitors ◽  
Automated Method ◽  
The Neural Network ◽  
On Line ◽  
Cosmic Ray Flux

An automated method is proposed for assessing the state of the cosmic ray flux on the base of neural networks. The method allows using the data of neutron monitors to determine the state of the cosmic ray flux in accordance with the a priori specified states of the neural network. The paper evaluates the method and presents the results of its application during periods of increased solar activity and magnetic storms. The possibility of realizing the method on-line is demonstrated.

scholarly journals Signs of geoeffective space weather events in cosmic rays during the first half of the solar cycle 24

2021 ◽  
pp. 119-124
Author(s):  
Agnieszka Gil ◽  
Renata Modzelewska ◽  
Szczepan Moskwa ◽  
Agnieszka Siluszyk ◽  
Marek Siluszyk ◽  
...  
Keyword(s):  
Solar Cycle ◽  
Space Weather ◽  
Transmission Lines ◽  
Cosmic Ray ◽  
Neutron Monitors ◽  
Time Intervals ◽  
Forbush Decreases ◽  
Solar Cycle 24 ◽  
Cycle 24 ◽  
Galactic Cosmic Ray

Solar originating events are continually evident in galactic cosmic ray (GCR) flux registered at the ground by neutron monitors. We analyze time intervals of sporadic Forbush decreases (Fd) observed by neutron monitors (NM) during the first half of solar cycle 24. We consider NMs data, as well as, solar, heliospheric and geoma - gnetic activity parameters, around those periods, using different mathematical tools. Subsequently, an impact of space weather phenomena on energy infrastructure is well known, in the further step we consider logs from one of the Polish transmission lines operators during the time intervals of Fds. Based on the data from the Ins- titute of Meteorology and Water Management-Polish National Research Institute we exclude from the analysis the weather-related failures. We found that the increase in the superposed averaged number of failures appears around Forbush decreases.

RENDIMENTO DE CULTIVARES DE CAUPI (Vigna unguiculata L Walp.) SUBMETIDAS À DIFERENTES LÂMINAS DE IRRIGAÇÃO

Irriga ◽  
1999 ◽  
Vol 4 (3) ◽  
pp. 139-144 ◽  
Author(s):  
Gianini Peixoto Bezerra Lima ◽  
José Vanglesio de Aguiar ◽  
Raimundo Nonato Távora Costa ◽  
Vital Pedro da Silva Paz
Keyword(s):  
Vigna Unguiculata ◽  
Irrigation System ◽  
Northeast Brazil ◽  
Marginal Product ◽  
Applied Water ◽  
Cowpea Cultivars ◽  
The North ◽  
Significant Difference ◽  
Caixa Postal ◽  
Water Depths

RENDIMENTO DE CULTIVARES DE CAUPI (Vigna unguiculata L Walp.) SUBMETIDAS À DIFERENTES LÂMINAS DE IRRIGAÇÃO1       Gianini Peixoto Bezerra Lima José Vanglesio de Aguiar Raimundo Nonato Távora Costa Universidade Federal do Ceará – Departamento de Engenharia Agrícola. Campus do Pici. Bloco 804. CEP 60455-760 – Fortaleza-CE Vital Pedro da Silva Paz Escola Superior de Agricultura Luiz de Queiroz – Departamento de Engenharia Rural, bolsista da FAPESP. Av. Pádua Dias, 11 – Caixa Postal 11. 13418-900 – Piracicaba-SP       1 RESUMO       O caupi é um dos cultivos mais tradicionais do Norte e Nordeste do Brasil, constituindo alimento básico nestas regiões. Com este trabalho foi possível estabelecer relações entre a quantidade de água aplicada e produtividade de grãos, para três variedades de feijão caupi submetidas a diferentes lâminas de água. Para caracterização das lâminas de água foi utilizado um sistema de irrigação por aspersão convencional em linha. O controle da irrigação foi realizado a partir de tensiômetros instalados à 15 cm de profundidade. Os resultados mostraram que: i) a cultivar João Paulo II apresentou melhores resultados de produtividade para as lâminas de água aplicadas que variaram de T1 = 291,8 mm a T5 = 141,2 mm; ii) sob condições de reduzida disponibilidade de água, ou seja, menor lâmina aplicada, não ocorreu diferença estatística  para a produtividade entre as cultivares estudadas; e iii) para as condições do estudo, a cultivar Setentão apresentou a menor taxa de redução do produto marginal.       UNITERMOS: caupi, irrigação, função de produção       LIMA, G. P. B., AGUIAR, J. V., COSTA, R. N. T., PAZ, V. P. S. Responses OF cowpea cultivars (Vigna unguiculata L Walp) at differents irrigation deficits     2 ABSTRACT       The caupi is one of the most traditional cultivation of the north and northeast - Brazil, constituting a basic food in these areas. With this work it was possible to establish relationships between the amount of water applied and productivity of grains, for three caupi varieties submitted to different irrigation sheets. To diferentiate water depths in the irrigation system, the aspersion in line was used. The control of the irrigation was accomplished using tensiometers installed to 15 cm of depth. The results showed that: i) the João Paulo II variety presented better productivity for the applied water depths; ii) under reduced conditions of water avai lability for study conditions, these was no significant difference in the productivity reached among the cultivars studied; and iii) for the conditions of the study, the variety Setentão presented the smallest rate of reduction of the marginal product.       KEYWORDS: cowpea, irrigation, production function  

The possible regulatory mechanisms of aqueous, ethyl acetate and nhexane fractions of the Ribes khorassanicum extract on acute hypertension in rats

2020 ◽  
Vol 20 ◽  
Author(s):  
Reza Mohebbati ◽  
Yasamin Kamkar-De ◽  
Mohammad Naser Shafei
Keyword(s):  
Ethyl Acetate ◽  
Antihypertensive Effect ◽  
Cardiovascular Responses ◽  
Regulatory Mechanisms ◽  
Hypertensive Rats ◽  
Control Groups ◽  
Acute Hypertension ◽  
The North ◽  
Significant Difference ◽  
And Control

Objective: Our previous studies showed the antihypertensive effect of Ribes khorassanicum (R. khorassanicum), a medicinal herb growing in the North Khorasan Province of Iran. For further evaluation, the present study investigated the effect of n-hexane (HX), ethyl acetate (EA), and aqueous (AQ) fractions of hydroalcoholic R. khorassanicum extract on cardiovascular responses in angiotensin II (AngII) and NG-nitro-L-arginine methyl ester (L-NAME) hypertensive rats. Methods: Wistar rats were randomly divided into 11 groups (n=5): 1) control, 2) AngII (50 ng/kg, i.v), 3) AngII + losartan (10 mg/kg, i.p), 4) L-NAME (10 mg/kg, i.v), 5) L-NAME+ sodium nitroprusside (SNP) (50 mg/kg, i.p), 6,7,8) one dose of each fraction of R. khorassanicum (AQ/EA/HX (50 mg/kg, i.p)) +AngII, and 9,10,11) one dose of each fraction of R. khorassanicum (AQ/EA/HX (50 mg/kg, i.p)) + L-NAME. Treated rats received three fractions 30 min before the injection of L-NAME and AngII in separate groups. The cardiovascular parameters were recorded by the Power Lab instrument via an angiocath inserted into the femoral artery. The peak changes (∆) of mean arterial pressure (MAP), systolic blood pressure (SBP), and heart rate (HR) in treated groups were compared with those of the hypertensive and control groups. Result: AngII and L-NAME significantly increased ∆MAP and ∆SBP and attenuated by pretreatment of LOS and SNP, respectively. Pretreatment with polar (AQ) and semipolar (EA) fractions of R. khorassanicum reduced the peak changes of MAP and SBP in both AngII and L-NAME-treated groups. Only the fraction of the herb attenuated the HR increased in the L-NAME group. The HR in other groups did not demonstrate any significant difference. Conclusion: All fractions of R. khorassanicum have an antihypertensive effect. However, the effect of polar fractions is more salient. It is also conceivable that the antihypertensive effect of fractions is mostly mediated by the inhibition of AngII.

scholarly journals Effects of the solar wind termination shock and heliosheath on theheliospheric modulation of galactic and anomalous Helium

2004 ◽  
Vol 22 (8) ◽  
pp. 3063-3072 ◽  
Author(s):  
U. W. Langner ◽  
M. S. Potgieter
Keyword(s):  
Solar Wind ◽  
Cosmic Ray ◽  
Magnetic Polarity ◽  
Termination Shock ◽  
Shock Acceleration ◽  
Diffusive Shock Acceleration ◽  
Cosmic Ray Modulation ◽  
Low Energies ◽  
Solar Wind Termination Shock ◽  
Charge Sign

Abstract. The interest in the role of the solar wind termination shock and heliosheath in cosmic ray modulation studies has increased significantly as the Voyager 1 and 2 spacecraft approach the estimated position of the solar wind termination shock. The effect of the solar wind termination shock on charge-sign dependent modulation, as is experienced by galactic cosmic ray Helium (He++) and anomalous Helium (He+), is the main topic of this work, and is complementary to the previous work on protons, anti-protons, electrons, and positrons. The modulation of galactic and anomalous Helium is studied with a numerical model including a more fundamental and comprehensive set of diffusion coefficients, a solar wind termination shock with diffusive shock acceleration, a heliosheath and particle drifts. The model allows a comparison of modulation with and without a solar wind termination shock and is applicable to a number of cosmic ray species during both magnetic polarity cycles of the Sun. The modulation of Helium, including an anomalous component, is also done to establish charge-sign dependence at low energies. We found that the heliosheath is important for cosmic ray modulation and that its effect on modulation is very similar for protons and Helium. The local Helium interstellar spectrum may not be known at energies

scholarly journals Genome-wide SNPs redefines species boundaries and conservation units in the freshwater mussel genus Cyprogenia of North America

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kyung Seok Kim ◽  
Kevin J. Roe
Keyword(s):  
Phylogenetic Analyses ◽  
Freshwater Mussel ◽  
Conservation Strategies ◽  
Nucleotide Polymorphisms ◽  
Conservation Units ◽  
Genetic Structuring ◽  
The North ◽  
Snp Data ◽  
Genome Wide ◽  
Significant Difference

AbstractDetailed information on species delineation and population genetic structure is a prerequisite for designing effective restoration and conservation strategies for imperiled organisms. Phylogenomic and population genomic analyses based on genome-wide double digest restriction-site associated DNA sequencing (ddRAD-Seq) data has identified three allopatric lineages in the North American freshwater mussel genus Cyprogenia. Cyprogenia stegaria is restricted to the Eastern Highlands and displays little genetic structuring within this region. However, two allopatric lineages of C. aberti in the Ozark and Ouachita highlands exhibit substantial levels (mean uncorrected FST = 0.368) of genetic differentiation and each warrants recognition as a distinct evolutionary lineage. Lineages of Cyprogenia in the Ouachita and Ozark highlands are further subdivided reflecting structuring at the level of river systems. Species tree inference and species delimitation in a Bayesian framework using single nucleotide polymorphisms (SNP) data supported results from phylogenetic analyses, and supports three species of Cyprogenia over the currently recognized two species. A comparison of SNPs generated from both destructively and non-destructively collected samples revealed no significant difference in the SNP error rate, quality and amount of ddRAD sequence reads, indicating that nondestructive or trace samples can be effectively utilized to generate SNP data for organisms for which destructive sampling is not permitted.

scholarly journals Perceived quality of care among people with type 2 diabetes mellitus in the north east region of peninsular Malaysia

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Noorfariza Nordin ◽  
Suhaily Mohd Hairon ◽  
Najib Majdi Yaacob ◽  
Anees Abdul Hamid ◽  
Seoparjoo Azmel Mohd Isa ◽  
...  
Keyword(s):  
Quality Of Care ◽  
Perceived Quality ◽  
Peninsular Malaysia ◽  
North East ◽  
The North ◽  
East Region ◽  
Perceived Quality Of Care ◽  
Significant Difference

Abstract Background People with type 2 diabetes mellitus (T2DM) are best managed by a chronic care model that is associated with enhanced quality of care and improved patient outcome. Assessing patients’ perceived quality of care is crucial in improving the healthcare delivery system. Hence, this study determined the perceived quality of care among people with T2DM and explored its associations with (i) sociodemographic and clinical characteristics and (ii) types of healthcare clinics to guide future planning. Methods A cross-sectional study involving 20 primary healthcare clinics in the North East Region of Peninsular Malaysia and people with T2DM as the sampling unit was conducted from February to May 2019. The pro forma checklist, interview-guided Skala Kepuasan Interaksi Perubatan-11, and Patient Assessment of Chronic Illness Care (Malay version; PACIC-M) questionnaire were used for data collection. Univariate analysis and linear regression were used to determine the status of perceived quality of care and the factors associated with the perceived quality of care, respectively. Results Overall, data from 772 participants were analyzed. The majority was from the Malay ethnic group (95.6%) with a mean (standard deviation [SD]) glycated hemoglobin A1c (HbA1c) level of 8.91% (2.30). The median (interquartile range [IQR]) of the number of medical officers available at each clinic was 6 (7), with Family Doctor Concept (FDC) clinics having a higher number of medical officers than non-FDC clinics (p = 0.001). The overall mean (SD) PACIC-M score was 2.65 (0.54) with no significant difference between scores of patients treated in the two clinic types (p = 0.806). Higher perceived quality of care was associated with lower number of medical officers (adjusted regression coefficient [Adj.β], − 0.021; p-value [p], 0.001), and greater doctor–patient interaction in all domains: distress relief (Adj.β, 0.033; p, < 0.001), rapport (Adj.β, 0.056; p, < 0.001), and interaction outcome (Adj.β, 0.022; p, 0.003). Conclusion Although there was no significant difference found between clinic type, this study reflects that patients are comfortable when managed by the same doctor, which may support a better doctor-patient interaction. A larger specialized primary care workforce could improve diabetes care in Malaysia.

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