Influence of weather factors on the abundance and population dynamics of Spodoptera litura F. and Pieris brassicae L. on cabbage

In order to study the influence of weather factors on the abundance and population dynamics of Spodoptera litura F. and Pieris brassicae L. on cabbage, a field experiment was conducted. Larval population of S. litura ranged from 0.56 to 1.57 larvae/plant during 8 January to 12 February 2014 crop season while the highest peak was on 5 February 2014 (1.57 larvae/plant) at 29.5 0C temperature. In case of Pieris brassicae, larval population ranged from 0.58 to1.98 larvae/plant and the highest peak of P. brassicae was also on 5 February. The highest peak was on 5 February 2014 at 96% and 38% relative humidity of both maximum and minimum categories and the highest peak of P. brassicae was on 5 February. There was a strong positive correlation (r = 0.824 and r = 0.920) between population of Spodoptera litura and temperature (maximum and minimum). On the other hand, there was a negative correlation (r = -0.439) between population of S. litura and maximum relative humidity and a strong negative correlation (r = - 0.716) between population of S. litura and minimum relative humidity. The population of Pieris brassicae was positively correlated (r = 0.899 and r = 0.956) with maximum and minimum temperatures. There was a negative correlation (r = -0.443) between population of P. brassicae and maximum relative humidity and a strong negative correlation (r = - 0.645) between population of P. brassicae and minimum relative humidity.SAARC J. Agri., 15(1): 13-21 (2017)

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Relationship between Weather Parameters and Incidence of Gram Pod Borer, Helicoverpa armigera on Chickpea

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-5818 ◽

2021 ◽

Author(s):

Keshav Mehra ◽

Veer Singh

Keyword(s):

Relative Humidity ◽

Negative Correlation ◽

Significant Positive Correlation ◽

Significant Negative Correlation ◽

Larval Population ◽

Positive Correlation ◽

Minimum Relative Humidity ◽

Pod Borer ◽

Sunshine Hours ◽

Weather Parameters

Background: Chickpea, Cicer arietinum which is considered as a “King of pulses” get adversely affected by several biotic and abiotic stresses, out of which gram pod borer, Helicoverpa armigera (Hübner) is the major one. The damage caused by H. armigera starts from vegetative growth and continues till maturity of the crop. This pest is causes 25 to 70 per cent pod damage in chickpea but in favorable conditions pod damage goes upto 95 per cent. Methods: Present study was carried out during, rabi, 2014-15 and 2015-16 at Research Farm, College of Agriculture, Bikaner (Rajasthan). Correlation coefficient was worked out with weather parameters such as temperature (maximum and minimum), relative humidity (maximum and minimum), rainfall and sunshine hours. Multiple linear forms of regression model were also used to assess the effect of the weather parameters on the incidence of pod borer. Result: The studies revealed that peak larval population of gram pod borer was recorded in the second fortnight of February thereafter, population declined abruptly. The larval population of pod borer on chickpea occurred low at vegetative and flowering stages and high at pod formation as well as at grain developmental stages. The temperature (maximum and minimum) and sunshine hours had significant positive correlation with larval population during rabi, 2015-16. The maximum relative humidity showed significant negative correlation during rabi, 2015-16 whereas, minimum relative humidity showed significant negative correlation with larval population during both the seasons. The rainfall showed significant positive correlation during rabi, 2014-15.

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Population dynamics of major defoliators (semiloopers and tobacco caterpillar) in soybean crop

Legume Research - An International Journal ◽

10.18805/lr.v0iof.4483 ◽

2016 ◽

Author(s):

S. Ramesh Babu ◽

Prahlad Kumar Meena ◽

Ramgopal Dudwal

Keyword(s):

Population Dynamics ◽

Spodoptera Litura ◽

Pheromone Trap ◽

Peak Activity ◽

Weather Factors ◽

Larval Population ◽

Soybean Crop ◽

Weather Parameters ◽

Trap Catches ◽

Tobacco Caterpillar

A study was carried out to find out the effect of various weather parameters on the occurrence of major defoliators in soybean crop. Semilooper larval population was recorded late July/early August and their peak activity observed during 33-34, 33-36 and 37-39 standard weeks, in 2012, 2013 and 2014, respectively. Among the weather factors, morning relative humidity showed significant (r=0.954) and positively, highly influence on the larval population per mrl whereas evening humidity (r=-0.644) and sunshine hrs (r=-0.367) negatively and significantly influence the larval population per mrl. The various weather parameters significantly caused 92 per cent variations in larval population per mrl. The moth catches of Spodoptera litura increased from late-August to late-September and this trend was almost similar in different kharif seasons observed. Larval population of S. litura positively correlated with pheromone trap catches during 2014.

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Spatial Variation of the Relationship between PM2.5Concentrations and Meteorological Parameters in China

BioMed Research International ◽

10.1155/2015/684618 ◽

2015 ◽

Vol 2015 ◽

pp. 1-15 ◽

Cited By ~ 10

Author(s):

Gang Lin ◽

Jingying Fu ◽

Dong Jiang ◽

Jianhua Wang ◽

Qiao Wang ◽

...

Keyword(s):

Negative Correlation ◽

Meteorological Parameters ◽

Semiarid Region ◽

Strong Positive Correlation ◽

Annual Average ◽

Strong Negative Correlation ◽

Positive Correlation ◽

Humid Region ◽

The Relationship ◽

Warm Temperate

Epidemiological studies around the world have reported that fine particulate matter (PM2.5) is closely associated with human health. The distribution of PM2.5concentrations is influenced by multiple geographic and socioeconomic factors. Using a remote-sensing-derived PM2.5dataset, this paper explores the relationship between PM2.5concentrations and meteorological parameters and their spatial variance in China for the period 2001–2010. The spatial variations of the relationships between the annual average PM2.5, the annual average precipitation (AAP), and the annual average temperature (AAT) were evaluated using the Geographically Weighted Regression (GWR) model. The results indicated that PM2.5had a strong and stable correlation with meteorological parameters. In particular, PM2.5had a negative correlation with precipitation and a positive correlation with temperature. In addition, the relationship between the variables changed over space, and the strong negative correlation between PM2.5and the AAP mainly appeared in the warm temperate semihumid region and northern subtropical humid region in 2001 and 2010, with some localized differences. The strong positive correlation between the PM2.5and the AAT mainly occurred in the mid-temperate semiarid region, the humid, semihumid, and semiarid warm temperate regions, and the northern subtropical humid region in 2001 and 2010.

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The effects of cardiac rehabilitation on haemodynamic parameters measured by impedance cardiography in patients with coronary artery disease

Vojnosanitetski pregled ◽

10.2298/vsp200810126s ◽

2020 ◽

pp. 126-126

Author(s):

Milovan Stojanovic ◽

Marina Deljanin-Ilic ◽

Stevan Ilic ◽

Dejan Petrovic ◽

Bojan Ilic

Keyword(s):

Coronary Artery Disease ◽

Negative Correlation ◽

Impedance Cardiography ◽

Exercise Stress ◽

Strong Positive Correlation ◽

Physical Strain ◽

Strong Negative Correlation ◽

Positive Correlation ◽

Strain Tolerance ◽

Artery Disease

Background / Aim. Well-organized cardiovascular rehabilitation (CVR) reduces cardiovascular burden by influencing cardiovascular risk factors, improving the quality of life and reducing mortality and hospital readmission. However, its effects on hemodynamic status are largely unknown. The aim of our study was to evaluate the influence of three-week CVR program on hemodynamic status and to investigate if there is a correlation between physical strain tolerance and hemodynamic parameters measured by impedance cardiography (ICG) before and after CVR program in patients with coronary artery disease. Methods. Fifty-two patients attended a three-week CVR program. At the beginning and at the end of rehabilitation program laboratory tests, exercise stress tests (EST) and ICG measurements were taken. Results. Patients showed better strain tolerance on the second exercise stress test (EST2) by achieving higher strain level (Z=2,315; p=0,021) and longer duration of test (Z=2,305; p=0,021). There was a strong positive correlation between the level of EST2 and cardiac output (CO) (r=0,538; p<0,001) and stroke volume (SV) (r=0,380; p=0,017) on the second ICG (ICG2). Also, there was a strong negative correlation between EST2 level and systemic vascular resistance (SVR) (r=-0,472; p=0,002) and SVR index (SSVRI) (r=-0,407; p=0,010) on ICG2. There was a strong positive correlation between EST2 duration and CO (r=0.517; p=0.001) as well as between EST2 duration and SV (r=0.340; p=0.034), and a strong negative correlation between EST2 duration and SVR (r=-0.504; p=0.001) as well as between EST2 duration and SVRI (r=-0.448; p=0.004), according to ICG2. Conclusion. Our study showed that a well-designed CVR program can lead to better physical strain tolerance. Furthermore, CVR led to a significant positive correlation between EST and cardiac output as well as between EST and stroke volume measured by ICG. On the other hand, there was a significant negative correlation between EST and vascular related parameters according to ICG at the end of the CVR program.

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Population dynamics of exotic rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) on coconut as influenced by weather factors and natural enemies

Journal of Plantation Crops ◽

10.25081/jpc.2020.v48.i2.6370 ◽

2020 ◽

pp. 120-125

Author(s):

K. Elango ◽

S. Jeyarajan Nelson

Keyword(s):

Population Dynamics ◽

Negative Correlation ◽

Natural Enemies ◽

Tamil Nadu ◽

Abiotic Factors ◽

Climatic Conditions ◽

Weekly Interval ◽

Maximum Temperature ◽

Weather Factors ◽

Extent Of Damage

The rugose spiralling whitefly, Aleurodicus rugioperculatus Martin is a new exotic pest occurring in several crops including coconut since 2016 in India. Due to variation in the agro-climatic conditions of different regions, arthropods show varying trends in their incidence also in nature and extent of damage to the crop. Besides, abiotic factors also play a key role in determining the incidence and dominance of a particular pest and their natural enemies in a crop ecosystem. The population dynamics of new exotic whitefly species, A. rugioperculatus and their associated natural enemies was assessed on five-year-old Chowghat Orange Dwarf coconut trees at Coconut Farm of Tamil Nadu Agricultural University. The study indicated that RSW was found throughout the year on coconut and the observation recorded on weekly interval basis shows that A. rugioperculatus population escalated from the first week of July 2018 (130.8 nymphs/leaf/frond) reaching the maximum during the first week of October (161.0 nymphs/leaf/frond) which subsequently dwindled to a minimum during April. The parasitisation by E. guadeloupae on RSW ranged from 31.60 percent in Aug. 2018 to 57.60 percent in December 2018. The association of biotic and abiotic factors with A. rugioperculatus population showed a negative correlation with E. guadeloupae and C. montrouzieri. There was a significant positive correlation between maximum temperature and minimum temperature as well as relative humidity. However, rainfall showed a negative correlation with A. rugioperculatus population.

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Meteorological parameter anomalies and anomalous radio propagation over Nigeria

Nigeria Journal of Pure and Applied Physics ◽

10.4314/njpap.v9i1.7 ◽

2020 ◽

Vol 9 (1) ◽

pp. 34-50

Author(s):

I. Emmanuel ◽

K.D. Adedayo ◽

B. Adeyemi ◽

O.S. Ojo

Keyword(s):

Spatial Distribution ◽

Relative Humidity ◽

Negative Correlation ◽

Meteorological Parameter ◽

Radio Propagation ◽

Monthly Variation ◽

Wet Season ◽

Strong Negative Correlation ◽

Positive Correlation ◽

Seasonal Movement

Distribution and variation of anomalous radio propagation, temperature and relative humidity anomalies were obtained and analyzed using six years (2010-2015) Era interim data. Seasonal spatial distribution of refractivity gradient and its components were analyzed. The result showed that about 90% of wet component contributed to the variation of refractivity gradient. Highest range of refractivity gradients and its wet components were obtained during the wet season. The result of correlation between ducting occurrence and temperature showed strong negative correlation except in Lagos where positive correlation of 3% was observed. However, positive correlation which ranges between 39% and 70% exist between duct occurrence and relative humidity except in Lagos in Nigeria. Refractivity gradients, relative humidity anomaly and temperature experience a monthly variation. These variations can be attributed to the seasonal movement of inter-tropical discontinuity (ITD) across Nigeria. Keywords: anomalous, anomaly, correlation, ITD

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Relationship Between Sperm Quality and Male Reproductive Hormones Among Male Partners with Fertility Complications: Attending CHUB

Rwanda Journal of Medicine and Health Sciences ◽

10.4314/rjmhs.v3i3.4 ◽

2020 ◽

Vol 3 (3) ◽

pp. 315-328

Author(s):

Herbert Mapira Tendayi ◽

Jerome Ndayisenga ◽

Solange Nyiramahirwe ◽

Jacqueline Mukanshuti ◽

Valens Karenzi ◽

...

Keyword(s):

Sperm Motility ◽

Negative Correlation ◽

Sperm Quality ◽

Sperm Count ◽

Reproductive Hormones ◽

Strong Positive Correlation ◽

Male Partners ◽

Strong Negative Correlation ◽

Cross Sectional ◽

Positive Correlation

Background Infertility remains a highly prevalent global condition in the second decade of the new millennium. Reproductive hormones determine sperm quality as they initiate and maintain spermatogenesis. Hormonal imbalance can cause abnormal sperm quality that can be treated by hormonal replacement therapy. Objective To assess the relationship between sperm quality and male reproductive hormones among male partners with fertility complications attending CHUB. Methods The study was a descriptive cross-sectional, and a convenient sampling strategy was used to recruit subjects at CHUB. Sixty-two male subjects with fertility complications provided both semen and blood sample to analyze sperm quality and reproductive hormones. Descriptive statistics were used to analyze data. Results Both FSH and LH showed a strong negative correlation with sperm count which is more profound with FSH (r= -0.722) than LH (r= -0.545). Testosterone showed a strong positive correlation with sperm count (r= 0.712). FSH and LH showed a negative correlation with sperm motility which is more profound in FSH (r= -0.312) than LH (r= -0.302). Testosterone also showed a positive correlation with sperm motility (r= 0.360). Conclusion Our study found a correlation between sperm quality and male reproductive hormones. We further suggest other studies to investigate predictive power of male reproductive hormones. Rwanda J Med Health Sci 2020;3(3):315-328

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An examination of jump kinematics in dogs over increasing hurdle heights

Comparative Exercise Physiology ◽

10.3920/cep150037 ◽

2016 ◽

Vol 12 (2) ◽

pp. 91-98 ◽

Cited By ~ 4

Author(s):

E. Birch ◽

A. Carter ◽

J. Boyd

Keyword(s):

Lumbar Spine ◽

Negative Correlation ◽

Maximum Height ◽

Strong Positive Correlation ◽

Kinematic Parameters ◽

Strong Negative Correlation ◽

Positive Correlation ◽

Sports Science ◽

Dorsal Aspect ◽

Dorsal Extension

Research examining kinematic parameters of the canine athlete is markedly behind equivalent human and equine research. With increasing participation and popularity, canine sports science needs to bridge this gap with comparable equine research. The aim of this study was to examine changes to specific kinematic parameters as hurdle height increases. Twenty border collies and border collie crosses were analysed jumping over a single hurdle at increasing heights, starting with a pole on the floor and increasing to a maximum height of 65 cm. Length of trajectory and jump speed were analysed, alongside apparent (without the use of markers) neck, lumbar spine and shoulder angles using Dartfish software. For each dog, the percentage of the hurdle height in relation to their height at the dorsal aspect of the scapula (withers) was used to normalise the dogs evenly. Overall jump speed decreased as percentage height increased (P<0.001), with a strong negative correlation between the two (r=-0.815). Length of trajectory significantly increased with percentage height (P<0.001) with a strong positive correlation between the two (r=0.740). However, length of trajectory decreased when a dog jumped ≥126% of its height to the withers. This is supported by a significantly more flexed apparent neck angle upon landing at this percentage height (P<0.001). Apparent lumbar spine angles showed greater dorsal extension upon landing as percentage height increased (P<0.001). Apparent shoulder angles become significantly more flexed as percentage height increased during the suspension phase of the jump (P<0.001). These results suggest that dogs significantly alter their jump kinematics as hurdle height increases.

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Data flows and the digital economy: information as a mobile factor of production

Digital Policy Regulation and Governance ◽

10.1108/dprg-08-2018-0044 ◽

2019 ◽

Vol 21 (1) ◽

pp. 71-87 ◽

Cited By ~ 6

Author(s):

Milton Mueller ◽

Karl Grindal

Keyword(s):

Negative Correlation ◽

Digital Economy ◽

Strong Positive Correlation ◽

Digital Information ◽

Information Flows ◽

Web Traffic ◽

Strong Negative Correlation ◽

Content Type ◽

Data Flows ◽

Balance Of Trade

Purpose This paper aims to analyze the direction and balance of transnational information flows and look at how nonpriced digital information exchanges related to international trade in goods and services. Design/methodology/approach The authors obtained quantitative data about Web-related data flows between countries and regions using Telegeography data on “Server Location as a Percentage of Top Websites.” They then explore how those flows are correlated to trade in goods. Findings Web traffic is highly transnational. More than half of the top 100 websites in 9 of the world’s 13 sub-regions are hosted in the USA. More than 15 per cent of the top 100 websites in 9 of the 13 subregions are hosted in Western Europe. East Asia has the largest negative balance in the relationship between incoming and outgoing Web requests. The authors found a very strong negative correlation (−0.878) between Web traffic balances and the balance of trade in goods across all subregions. A similarly strong positive correlation was found with services trade; however, the incompleteness of the data does not allow for strong conclusions yet. Research limitations/implications Further research is needed to correlate Web traffic flows with capital flows. The authors also do not have a well-developed theory to explain the strong negative correlation between information flows and goods trade. Practical implications The data and analysis have useful implications for digital economy policy. It indicates that digital protectionism of the sort practice by China may succeed in increasing domestic producers’ share of Web requests, but does not make them globally competitive. The strong negative correlation between the balance of unpriced Web information and the balance of trade in goods indicates interdependence rather than domination, challenging narratives that information flow imbalances are caused by market power of the big platforms. Social implications The paper demonstrates the degree to which unpriced digital exchanges are transnational and how various countries are more or less globally competitive in the supply of information that the rest of the world finds attractive. Originality/value No other published papers have used the data on website traffic data, and previous research has not explored empirically the correlation between information flows and goods trade.

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Timing during transitions in Bengalese finch song: implications for motor sequencing

Journal of Neurophysiology ◽

10.1152/jn.00296.2017 ◽

2017 ◽

Vol 118 (3) ◽

pp. 1556-1566 ◽

Cited By ~ 3

Author(s):

Todd W. Troyer ◽

Michael S. Brainard ◽

Kristofer E. Bouchard

Keyword(s):

Negative Correlation ◽

Transition Probabilities ◽

Transition Probability ◽

Strong Positive Correlation ◽

Strong Negative Correlation ◽

Bengalese Finch ◽

Divergence Points ◽

Probabilistic Sequences ◽

Action Sequencing ◽

The Relationship

To investigate mechanisms of action sequencing, we examined the relationship between timing and sequencing of syllables in Bengalese finch song. An individual’s song comprises acoustically distinct syllables organized into probabilistic sequences: a given syllable potentially can transition to several different syllables (divergence points), and several different syllables can transition to a given syllable (convergence points). In agreement with previous studies, we found that more probable transitions at divergence points occur with shorter intersyllable gaps. One intuition for this relationship is that selection between syllables reflects a competitive branching process, in which stronger links to one syllable lead to both higher probabilities and shorter latencies for transitions to that syllable vs. competing alternatives. However, we found that simulations of competitive race models result in overlapping winning-time distributions for competing outcomes and fail to replicate the strong negative correlation between probability and gap duration found in song data. Further investigation of song structure revealed strong positive correlation between gap durations for transitions that share a common convergent point. Such transitions are not related by a common competitive process, but instead reflect a common terminal syllable. In contrast to gap durations, transition probabilities were not correlated at convergence points. Together, our data suggest that syllable selection happens early during the gap, with gap timing determined chiefly by the latency to syllable initiation. This may result from a process in which probabilistic sequencing is first stabilized, followed by a shortening of the latency to syllables that are sung more often. NEW & NOTEWORTHY Bengalese finch songs consist of probabilistic sequences of syllables. Previous studies revealed a strong negative correlation between transition probability and the duration of intersyllable gaps. We show here that the negative correlation is inconsistent with previous suggestions that timing at syllable transitions is governed by a race between competing alternatives. Rather, the data suggest that syllable selection happens early during the gap, with gap timing determined chiefly by the latency to syllable initiation.

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