Temperature Preference and Avoidance Responses of the Crayfish, Orconectes obscurus, and Associated Statistical Problems

1982 ◽  
Vol 39 (4) ◽  
pp. 548-553 ◽  
Author(s):  
Dilip Mathur ◽  
Robert M. Schutsky ◽  
Edmund J. Purdy Jr.

Acute temperature selection and avoidance responses of the crayfish, Orconectes obscurus, acclimated at field collection temperatures of 1.5–26.0 °C and determined in a spatial thermal gradient, were similar to those noted for fishes. Acclimation temperature was positively correlated with the acute preferred and avoided temperatures; both were several degrees higher than the acclimation temperature. A large proportion of the total variance in these data was unexplained. Most variable responses occurred at low acclimation temperatures. The estimated final preferred temperature ranged from 29.8 to 33.9 °C depending upon the method of calculation. Methods of estimating final preferenda from acute tests are considered arbitrary due to statistical problems and the associated high variability. Statistical problems were also noted in the determination of avoidance temperatures of crayfish due to nonindependence of observations on the same organism. No differences were noted (P < 0.05) between the preferred or avoided temperatures when the direction of field temperatures was rising or falling. A statistical comparison of the new and published data on this species revealed general similarities, particularly over an acclimation temperature range of 18.0–30.0 °C. The analysis minimizes the importance of site-specific studies on this species using the current acute testing methods.Key words: crayfish, temperature preference, avoidance, populational variation, statistics, experimental and statistical problems

Vaccines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 211
Author(s):  
Anna Malkova ◽  
Dmitriy Kudlay ◽  
Igor Kudryavtsev ◽  
Anna Starshinova ◽  
Piotr Yablonskiy ◽  
...  

According to an analysis of published data, only 20% of patients with the new coronavirus infection develop severe life-threatening complications. Currently, there are no known biomarkers, the determination of which before the onset of the disease would allow assessing the likelihood of its severe course. The purpose of this literature review was to analyze possible genetic factors characterizing the immune response to the new coronavirus infection that could be associated with the expression of angiotension-converting enzyme 2 (ACE-2) and related proteins as predictors of severe Corona virus disease 2019 (COVID-19). We analyzed original articles published in Medline, PubMed and Scopus databases from December 2019 to November 2020. For searching articles, we used the following keywords: New coronavirus infection, Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), COVID-19, severe course, complications, thrombosis, cytokine storm, ACE-2, biomarkers. In total, 3714 publications were selected using the keywords, of which 8 were in congruence with all the criteria. The literature analysis of the association of immunogenic characteristics and the expression of ACE-2 and related proteins with the development of severe COVID-19 revealed following genetic factors: HLA-B*46:01 genotype, CXCR6 gene hypoexpression, CCR9 gene expression, TLR7, rs150892504 mutations in the ERAP2 gene, overexpression of wild-type ACE-2, TMPRSS2 and its different polymorphisms. Genes, associated with the severe course, are more common among men. According to the analysis data, it can be assumed that there are population differences. However, the diagnostic significance of the markers described must be confirmed with additional clinical studies.


1949 ◽  
Vol 22 (1) ◽  
pp. 259-262
Author(s):  
J. F. Morley

Abstract These experiments indicate that softeners can influence abrasion resistance, as measured by laboratory machines, in some manner other than by altering the stress-strain properties of the rubber. One possible explanation is that the softener acts as a lubricant to the abrasive surface. Since this surface, in laboratory abrasion-testing machines, is relatively small, and comes repeatedly into contact with the rubber under test, it seems possible that it may become coated with a thin layer of softener that reduces its abrasive power. It would be interesting in this connection to try an abrasive machine in which a long continuous strip of abrasive material was used, no part of it being used more than once, so as to eliminate or minimize this lubricating effect. The fact that the effect of the softener is more pronounced on the du Pont than on the Akron-Croydon machine lends support to the lubrication hypothesis, because on the former machine the rate of wear per unit area of abrasive is much greater. Thus in the present tests the volume of rubber abraded per hr. per sq. cm. of abrasive surface ranges from 0.03 to 0.11 cc. on the du Pont machine and from 0.0035 to 0.0045 cc. on the Akron-Croydon machine. On the other hand, if the softener acts as a lubricant, it would be expected to reduce considerably the friction between the abrasive and the rubber and hence the energy used in dragging the rubber over the abrasive surface. The energy figures given in the right-hand columns of Tables 1 and 3, however, show that there is relatively little variation between the different rubbers. As a test of the lubrication hypothesis, it would be of interest to vary the conditions of test so that approximately the same amount of rubber per unit area of abrasive is abraded in a given time on both machines; this should show whether the phenomena observed under the present test conditions are due solely to the difference in rate of wear or to an inherent difference in the type of wear on the two machines. This could most conveniently be done by considerably reducing the load on the du Pont machine. In the original work on this machine the load was standardized at 8 pounds, but no figures are quoted to show how abrasion loss varies with the load. As an addition to the present investigation, it is proposed to examine the effect of this variation with special reference to rubbers containing various amounts and types of softener. Published data on the influence of softeners on the road wear of tire rubbers do not indicate anything like such large effects as are shown by the du Pont machine. This throws some doubt on the value of this machine for testing tire tread rubbers, a conclusion which is confirmed by information obtained from other workers.


2021 ◽  
Author(s):  
Larisa A. Chipiga ◽  
Anna E. Petrova ◽  
Artem A. Mosunov ◽  
Laura T. Naurzbaeva ◽  
Stanislaus M. Kushnarenko ◽  
...  

In connection with the constantly increasing use of monoclonal antibodies labeled with 89Zr, in clinical practice, it is urgent to study their pharmacokinetics with the determination, based on the data obtained, of absorbed doses in tumor foci, as well as intact organs and tissues, and effective doses of patients. To date, there are a limited number of studies that provide patient doses for diagnostic examinations using 89Zr-labeled monoclonal antibodies. In this regard, the purpose of this work was to assess the biodistribution of various monoclonal antibodies (ramucirumab, trastuzumab, atezolizumab) labeled with 89Zr, based on published data, with subsequent calculation of absorbed doses in radiosensitive organs and tissues and effective doses of patients. Based on the analysis of experimental data on the biodistribution of monoclonal antibodies labeled with 89Zr for the diagnosis of oncological diseases from the available literature sources and our own assessments, it has been concluded that the results of the determination of absorbed in organs and tissues and effective doses are inconsistent. The absorbed doses in organs, according to different literature sources, vary up to an order of magnitude within one organ and reach 440 mGy per examination, the effective dose varies from 3 to 112 mSv per examination. This may be due to differences in study design, radiometry and dose assessment methods. Comparison with doses obtained on the basis of a general model of biodistribution of monoclonal antibodies demonstrates the possibility of using this model for a rough estimate of internal doses of patients. However, for a more accurate assessment, it is necessary to standardize approaches to the determination of internal radiation doses using the most effective methodological solutions and software products.


2001 ◽  
Vol 204 (1) ◽  
pp. 39-45 ◽  
Author(s):  
F.B. Jensen ◽  
T. Wang ◽  
J. Brahm

Unidirectional (36)Cl(−) efflux via the red blood cell anion exchanger was measured under Cl(−) self-exchange conditions (i.e. no net flow of anions) in rainbow trout Oncorhynchus mykiss and red-eared freshwater turtle Trachemys scripta to examine the effects of acute temperature changes and acclimation temperature on this process. We also evaluated the possible adaptation of anion exchange to different temperature regimes by including our previously published data on other animals. An acute temperature increase caused a significant increase in the rate constant (k) for unidirectional Cl(−) efflux in rainbow trout and freshwater turtle. After 3 weeks of temperature acclimation, 5 degrees C-acclimated rainbow trout showed only marginally higher Cl(−) transport rates than 15 degrees C-acclimated trout when compared at the same temperature. Apparent activation energies for red blood cell Cl(−) exchange in trout and turtle were lower than values reported in endothermic animals. The Q(10) for red blood cell anion exchange was 2.0 in trout and 2.3 in turtle, values close to those for CO(2) excretion, suggesting that, in ectothermic animals, the temperature sensitivity of band-3-mediated anion exchange matches the temperature sensitivity of CO(2) transport (where red blood cell Cl(−)/HCO(3)(−) exchange is a rate-limiting step). In endotherms, such as man and chicken, Q(10) values for red blood cell anion exchange are considerably higher but are no obstacle to CO(2) transport, because body temperature is normally kept constant at values at which anion exchange rates are high. When compared at constant temperature, red blood cell Cl(−) permeability shows large differences among species (trout, carp, eel, cod, turtle, alligator, chicken and man). Cl(−) permeabilities are, however, remarkable similar when compared at preferred body temperatures, suggesting an appropriate evolutionary adaptation of red blood cell anion exchange function to the different thermal niches occupied by animals.


1990 ◽  
Vol 68 (4-5) ◽  
pp. 365-368 ◽  
Author(s):  
K. Hussein ◽  
O. Babaky

In this paper, we study a calculation of the transition elements [Formula: see text] between electronic states of the diatomic molecules Na2. We show the necessary selection rules for the determination of these operators by a method of analytical integration on the variable [Formula: see text], combined with a numerical integration to fifth order. The values found by this simple method of calculation are very reasonable and show that the important transitions [Formula: see text], [Formula: see text]; and [Formula: see text] of the dimer Na2 are dipolar. [Traduit par la revue]


2006 ◽  
Vol 80 (16) ◽  
pp. 7863-7872 ◽  
Author(s):  
Dean R. Thureen ◽  
Calvin L. Keeler

ABSTRACT Psittacid herpesvirus 1 (PsHV-1) is the causative agent of Pacheco's disease, an acute, highly contagious, and potentially lethal respiratory herpesvirus infection in psittacine birds, while infectious laryngotracheitis virus (ILTV) is a highly contagious and economically significant avian herpesvirus which is responsible for an acute respiratory disease limited to galliform birds. The complete genome sequence of PsHV-1 has been determined and compared to the ILTV sequence, assembled from published data. The PsHV-1 and ILTV genomes exhibit similar structural characteristics and are 163,025 bp and 148,665 bp in length, respectively. The PsHV-1 genome contains 73 predicted open reading frames (ORFs), while the ILTV genome contains 77 predicted ORFs. Both genomes contain an inversion in the unique long region similar to that observed in pseudorabies virus. PsHV-1 is closely related to ILTV, and it is proposed that it be assigned to the Iltovirus genus. These two avian herpesviruses represent a phylogenetically unique clade of alphaherpesviruses that are distinct from the Marek's disease-like viruses (Mardivirus). The determination of the complete genomic nucleotide sequences of PsHV-1 and ILTV provides a tool for further comparative and functional analysis of this unique class of avian alphaherpesviruses.


1993 ◽  
Vol 37 ◽  
pp. 697-709 ◽  
Author(s):  
Krassimir N. Stoev ◽  
Joseph F. Dlouhy

Nowadays x-ray fluorescence analysis is one of the major techniques for determination of trace elements. Vacuum operated Si (Li) .energy-dispersive x-ray spectrometers can analyze simultaneously up to 50 elements from Na (Z=11) to U (Z = 92) . Proper interpretation of the accumulated spectra requires correct solution of x-ray line overlap problems. In many cases knowledge of x-ray intensity ratios can make the procedure for resolving the overlapped peaks more reliable and reproducible. Measurements of radiative transition rates can also provide fundamental tests of theoretical atomic structure calculations. There are many other useful applications of x-ray emission rates in theoretical and experimental physics. On the other hand, there are differences in the published data, which suggests that x-ray intensity ratios are still not known with the necessary accuracy, and new measurements are useful and necessary.


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