Studies on Beetles of the Family Ptinidae. VI.—The Biology of Ptinus fur (L.) and P. sexpunctatus Panzer

1951 ◽  
Vol 42 (3) ◽  
pp. 499-511 ◽  
Author(s):  
R. W. Howe ◽  
H. D. Burges
Keyword(s):  
Rapid Development ◽  
Maximum Temperature ◽  
Continuous Series ◽  
Optimum Temperature ◽  
Emergence Period ◽  
Mature Adults ◽  
Large Numbers ◽  
The Family ◽  
The Mean ◽  
Pass Through

The development of Ptinus fur (L.) and P. sexpunctatus Panzer at 70 per cent. R.H. and several temperatures has been studied.The optimum temperature for rapid development of P. fur is about 23°C., at which temperature it completes its development in a mean period of 132·1 days on fishmeal. For P. sexpunctatus the optimum temperature for rapid development is slightly below 30°C., development being completed in approximately 111 days on wheatfeed at this temperature.Eggs of P. sexpunctatus, but not those of P. fur, hatch at 30°C., which is near the maximum temperature for development of P. fur.Larvae of P. fur normally moult three times at 23°C. on fishmeal, but some have an extra moult.Well defined diapause as mature larvae in cocoons occurs at low temperatures in some individuals of P. fur ; at 23°C. this lasts about 220 days after normal larvae have pupated ; the period at 20°C. is about 280 days. Diapause at this stage also occurs in P. sexpunctatus. In experiments, the development periods of the diapausing and non-diapausing larvae overlapped to form a continuous series.Some P. sexpunctatus pass through a period of quiescence as mature adults in cocoons ; at 23°C., this lasted 43·5 days on fishmeal and 103·0 days on wheatfeed (mean periods). In P. fur the pre-emergence period is 30 to 60 days, considerably longer than that of other warehouse Ptinids studied.Of the foods, wheatfeed allows the quickest development for both species, but fishmeal produces the heaviest beetles.The adult beetles live for several months. They require food and drinking water. Egg output is small, the mean number of eggs laid per female at 25°C. being 38·6 for P. fur and 21·3 for P. sexpunctatus.P. sexpunctatus was able to overwinter in an unheated outbuilding and could possibly become a pest on some foods.P. fur is unlikely to occur in large numbers, owing to its long development period, small egg output and tendency to larval diapause.

scholarly journals Mosquitofish avoid thermal stress by moving from open water to the shade of the mangrove Rhizophora mangle

2020 ◽  
Vol 637 ◽  
pp. 103-116
Author(s):  
IW Hendy ◽  
O Burt ◽  
S Clough ◽  
L Young ◽  
SM Cragg
Keyword(s):  
Thermal Stress ◽  
Thermal Stresses ◽  
Rhizophora Mangle ◽  
Open Water ◽  
Direct Access ◽  
Maximum Temperature ◽  
Mangrove Forests ◽  
Ocean Water ◽  
Mature Adults ◽  
Large Numbers

Mangrove trees provide environmental buffering for animals by reducing daytime water thermal maxima. Shade from Rhizophora mangle trees reduces thermal stress for the mosquitofish Gambusia affinis. Data were collected from mangrove forests in Quintana Roo, Mexico, at 2 sites: (1) Soliman Bay, a mangrove forest decoupled from direct ocean water, and (2) La Lunita with semi-direct access to ocean water. During cooler morning hours at Soliman Bay, large numbers of mosquitofish foraged in open channels. At the same time, few mosquitofish utilised shaded areas within the R. mangle prop roots. When channels exceeded water temperatures above 38°C, mosquitofish migrated into the shaded areas provided by R. mangle trees. Channel water reached a daytime maximum temperature of 46°C, while daytime-shaded R. mangle areas remained 6.2°C cooler. Temperature rise and abundance shifts were not found in La Lunita, which has water temperatures of 27 to 28°C throughout the day. Size distributions between both localities showed mosquitofish caught in Soliman Bay to be >10% smaller than the mosquitofish from La Lunita, which had a greater abundance of mature adults. In Soliman Bay, mosquitofish were small, and the thermal stresses may impose serious developmental impacts that would be reduced by occupying water shaded by R. mangle. Refuge from R. mangle provides environmental buffering for fish, and future increasing water temperatures may reveal a greater use of this little-known mechanism. This study provides an example of a mechanism whereby mangroves support intertidal biodiversity through environmental buffering.

Factors affecting the abundance of the copra beetle, Necrobia rufipes (Deg.) (Col., Cleridae)

1963 ◽  
Vol 53 (4) ◽  
pp. 671-680 ◽  
Author(s):  
F. Ashman
Keyword(s):  
Food Supply ◽  
Rapid Development ◽  
Adult Life ◽  
High Moisture Content ◽  
High Moisture ◽  
Factors Affecting ◽  
Complete Development ◽  
Large Numbers ◽  
The Mean ◽  
Effects Of Temperature

Some effects of temperature, relative humidity and food supply on the fecundity, length of adult life and rate of development of Necrobia rufipes (Deg.) are outlined.At 30°C. and 64–70 per cent. R.H., females laid few eggs when supplied with palm kernels as food, whereas when given freshly squashed larvae of Carpophilus dimidiatus (F.) as their only food supply they laid large numbers of eggs.When Aspergillus spp. commonly found on copra of high moisture content were cultured, conditioned and supplied as the only food at 30°C. and 81 per cent. R.H., newly emerged larvae died within two days. Complete mortality also occurred on palm kernels at 30°C. and 64–70 per cent. R.H., although a few larvae survived for 60 days.On copra alone, complete development occurred in all conditions attempted, except at 25°C. and 53 per cent. R.H. Development on this food was most rapid at 30°C. and 81 per cent. R.H. (mean period (larva + pupa) 66·5 days). The addition of fishmeal to copra reduced the mean period of development (larva + pupa) at 30°C. and 81 per cent. R.H. to 42·6 days. The shortest mean period of development (larva + pupa) recorded, 37·9 days, was with larvae of C. dimidiatus as food, at 30°C. and 64–70 per cent. R.H. Rapid development was also achieved by adding larvae of N. rufipes to a culture of Oryzaephihis mercator (Fauv.).

An old friend is better than two new ones? Approaches to market research in the context of digital transformation for the antitrust laws enforcement

2020 ◽  
pp. 37-55 ◽  
Author(s):  
A. E. Shastitko ◽  
O. A. Markova
Keyword(s):  
Business Models ◽  
Rapid Development ◽  
Digital Transformation ◽  
Market Definition ◽  
Type I ◽  
Type Ii ◽  
Digital Platforms ◽  
Advantages And Disadvantages ◽  
Pass Through ◽  
Type Ii Errors

Digital transformation has led to changes in business models of traditional players in the existing markets. What is more, new entrants and new markets appeared, in particular platforms and multisided markets. The emergence and rapid development of platforms are caused primarily by the existence of so called indirect network externalities. Regarding to this, a question arises of whether the existing instruments of competition law enforcement and market analysis are still relevant when analyzing markets with digital platforms? This paper aims at discussing advantages and disadvantages of using various tools to define markets with platforms. In particular, we define the features of the SSNIP test when being applyed to markets with platforms. Furthermore, we analyze adjustment in tests for platform market definition in terms of possible type I and type II errors. All in all, it turns out that to reduce the likelihood of type I and type II errors while applying market definition technique to markets with platforms one should consider the type of platform analyzed: transaction platforms without pass-through and non-transaction matching platforms should be tackled as players in a multisided market, whereas non-transaction platforms should be analyzed as players in several interrelated markets. However, if the platform is allowed to adjust prices, there emerges additional challenge that the regulator and companies may manipulate the results of SSNIP test by applying different models of competition.

scholarly journals Relaxation Times in Strictly Disk Systems

1971 ◽  
Vol 10 ◽  
pp. 15-19
Author(s):  
George B. Rybicki
Keyword(s):  
Numerical Experiments ◽  
Relaxation Times ◽  
Galactic Structure ◽  
Large Numbers ◽  
Order Of Magnitude ◽  
Vlasov Limit ◽  
The Mean ◽  
Gravitating Systems

AbstractIt is shown that the time of relaxation by particle encounters of self-gravitating systems in the plane interacting by 1/r2 forces is of the same order of magnitude as the mean orbit time. Therefore such a system does not have a Vlasov limit for large numbers of particles, unless appeal is made to some non-zero thickness of the disk. The relevance of this result to numerical experiments on galactic structure is discussed.

Disability in Schizophrenic Disorders

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
J. Wancata ◽  
M. Freidl ◽  
F. Friedrich ◽  
T. Matschnig ◽  
A. Unger ◽  
...  
Keyword(s):  
Hospital Admissions ◽  
Social Consequences ◽  
Subjective Burden ◽  
Social Contacts ◽  
Mothers And Fathers ◽  
Duration Of Illness ◽  
The Family ◽  
Different Types ◽  
Icd 10 ◽  
The Mean

Aims:The purpose of this study was to investigate disability among patients suffering from schizophrenia and to identify predictors of disability.Methods:101 patients from different types of psychiatric services in Vienna and diagnosed with schizophrenia according to ICD-10 were included. They were investigates by means of 36-Item self-administered version of the WHO Disability Assessment Schedule II (WHO-DAS-II) and the PANSS-scale. Patients’ mothers and fathers were asked to fill in the Family Problem Questionnaire.Results:The mean total score of the WHO-DAS-II was 74.1 (SD 21.9). When using weighted sub-scores the highest disability scores were found for social contacts, participation in society and household (means 2.58, 2.57 and 2.51 respectively). Using logistic regression, overall disability was positively associated with patient's age, overall severity of symptoms (PANSS) and number of previous hospital admissions. Overall disability was not associated with duration of illness and or patient's gender. The subjective burden experienced by patients’ fathers and mothers were increased by reduced social contacts and impaired participation in society, while we could not find an association with other domains of patient's disability (understanding, mobility, self-care, household).Conclusions:This study shows that schizophrenia results in disability in several domains. Family caregivers’ burden was predominantly increased by social consequences of schizophrenia.

GLOBAL FLUCTUATIONS FOR LINEAR STATISTICS OF β-JACOBI ENSEMBLES

2012 ◽  
Vol 01 (04) ◽  
pp. 1250013 ◽  
Author(s):  
IOANA DUMITRIU ◽  
ELLIOT PAQUETTE
Keyword(s):  
Gaussian Process ◽  
Covariance Matrix ◽  
Law Of Large Numbers ◽  
Test Functions ◽  
Linear Statistics ◽  
Jacobi Ensemble ◽  
Large Numbers ◽  
The Mean ◽  
Shifted Chebyshev Polynomial ◽  
Global Fluctuations

We study the global fluctuations for linear statistics of the form [Formula: see text] as n → ∞, for C1 functions f, and λ1, …, λn being the eigenvalues of a (general) β-Jacobi ensemble. The fluctuation from the mean [Formula: see text] turns out to be given asymptotically by a Gaussian process. We compute the covariance matrix for the process and show that it is diagonalized by a shifted Chebyshev polynomial basis; in addition, we analyze the deviation from the predicted mean for polynomial test functions, and we obtain a law of large numbers.

Hidradenitis suppurativa: Wie die Partner von Betroffenen psychosozial beeinträchtigt werden

2021 ◽  
pp. 1-3
Author(s):  
Uwe Gieler
Keyword(s):  
Disease Severity ◽  
Social Life ◽  
Hidradenitis Suppurativa ◽  
Life Quality ◽  
Psychosocial Burden ◽  
Wide Range ◽  
The Family ◽  
The Mean ◽  
Moderate Effect

<b>Background</b>: Hidradenitis suppurativa is a debilitating disease related to a great psychosocial burden in affected patients and subsequently also people around them. Patients’ partners as caregivers may indirectly experience wide range of devastating effects of the disease on their emotional and social life. <b>Objective:</b> The purpose of this study was to determine the QoL impairment in HS patients’ partners and to identify its aspects that are affected the most. Correlation between QoL burden and disease severity, duration, sex, age and smoking was also assessed. <b>Methods:</b> A total of 50 HS sufferers were assessed according to disease severity and their partners’ QoL was determined using the Family Dermatology Life Quality Index questionnaire. <b>Results:</b> The mean FDLQI for patients’ partners was 8.7 ± 6.8 points, indicating generally a moderate effect of HS on their life. Quality of partners’ life correlated significantly with disease severity but no correlation was found according to other factors. <b>Conclusion:</b> Hidradenitis suppurativa is a highly psychologically devastating disease not only for patients but also for their partners. It occurred to diminish partners’ QoL mostly by increasing daily expenditure but also other problems were often reported. Clinicians should be aware of these psychosocial implications, in order to provide optimal therapy of HS affected families by a multidisciplinary specialized management addressing both, patients and their cohabitants simultaneously.

scholarly journals Thermoregulation in colonies of africanized and hybrids with Caucasian, Italian and Carniolan Apis mellifera honey bees

1999 ◽  
Vol 42 (4) ◽  
Author(s):  
Vagner de Alencar Arnaut de Toledo ◽  
Regina Helena Nogueira-Couto
Keyword(s):  
Apis Mellifera ◽  
Honey Bees ◽  
Maximum Temperature ◽  
Tropical Region ◽  
Internal Temperature ◽  
Africanized Honey Bees ◽  
Significant Difference ◽  
The Mean ◽  
One Year ◽  
Brood Nest

This experiment was carried out to study the internal temperature regulation of a colony of Africanized honey bees (AFR), compared with hybrid Caucasian (CAU), Italian (ITA), and Carniolan (CAR) bees, during the period of one year and different size hives located in a sub-tropical region. The instant internal temperature, 33.7 ± 1.5° C for the AFR, 33.5 ± 1.4° C for the CAU, 33.7 ± 1.5° C for the ITA and 33.8 ± 1.4° C for the CAR, did not show any significant difference (P>0.05). The maximum temperature (36.1 ± 2.3° C) was statistically different (P<0.05) from the minimum (27.6 ± 5.3° C). There was no difference (P>0.05) in the mean internal temperature, between the nucleus (31.7 ± 6.3° C) and the brood nest (32.1 ± 5.3° C) measured between two and four o'clock in the afternoon.

Chemical characteristics and in situ ruminal parameters of barley for cattle: Comparison of the malting cultivar AC Metcalfe and five feed cultivars

2008 ◽  
Vol 88 (4) ◽  
pp. 711-719 ◽  
Author(s):  
Kenton J Hart ◽  
Brian G Rossnagel ◽  
Peiqiang Yu
Keyword(s):  
Nutritive Value ◽  
Degradation Kinetics ◽  
Starch Degradation ◽  
Barley Cultivars ◽  
Degradation Rates ◽  
Key Words Barley ◽  
In Situ Degradation ◽  
The Mean ◽  
Pass Through

The objective of this study was to compare the most widely grown barley cultivar in Canada, AC Metcalfe, a malting type barley, with five feed cultivars. Barley cultivars were grown at one location during 3 consecutive years and barley samples were milled to pass through a 1-mm screen and analysed to determine nutritive value. Additional samples were passed through a roller mill with a gap set at 1.12 mm and incubated ruminally for 0, 2, 4, 8, 12, 24, and 48 h in 3 dry Holstein cows fitted with rumen cannulae. The rate and extent of rumen digestion were estimated. AC Metcalfe had a higher (P < 0.001) concentration of NDF, and lower (P < 0.05) concentrations of non structural carbohydrates, starch, ADF, total digestible nutrients, and fermentable cell wall carbohydrates compared with the mean of the feed cultivars. The malting cultivar had a higher (P < 0.001) soluble DM fraction, lower (P < 0.05) CP and starch degradation rates, and a lower (P < 0.001) ruminally degradable starch concentration compared with the mean of the five feed cultivars. The results demonstrate that there are only small differences in terms of chemical composition and in situ degradation kinetics between the malting cultivar AC Metcalfe and the five feed cultivars of barley reported here. Key words: Barley, energy, protein, ruminants

Observations on 287 thunder-storms made at highfield house, near Nottingham, during the last nine years

1851 ◽  
Vol 5 ◽  
pp. 957-957
Keyword(s):  
Minimum Temperature ◽  
Maximum Temperature ◽  
Tabular Form ◽  
The Hours ◽  
The Mean ◽  
Atmospheric Phenomena ◽  
Rotatory Motion

The thunder-storms referred to in this communication are recorded in a tabular form., arranged according to their dates. In this table are given the date; the hour of the commencement of the storm; the mean height of the barometer to tenths of an inch; whether it is rising, stationary, or falling; the direction of the wind before the storm, during its continuance, and after its cessation; the maximum temperature on the day of the storm and on the day after; the minimum temperature on the night before and on the night after; and general remarks on the storms. This table is followed by remarks on particular storms recorded in it. In conclusion the author gives the results of his observations with reference to the number of storms in each year; the number in each month, with the hours at which they mostly occur in particular months; the number that have occurred with a rising, stationary, or falling barometer; the number in respect to the direction of the wind and of the current in which the storms moved; the number of storms that have occurred at the various heights of the maximum, and also of the minimum thermometer; the number in which the peculiar breeze that suddenly springs up on the commencement of thunder-storms has been well marked; the change in the direction of some of these storms, and indications of rotatory motion; and finally, the different atmospheric phenomena which have accompanied these storms.

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