The Standing Crop of Fish in Lakes

1955 ◽  
Vol 12 (4) ◽  
pp. 543-570 ◽  
Author(s):  
Kenneth D. Carlander
Keyword(s):  
Environmental Factors ◽  
Standing Crop ◽  
The Other ◽  
Warm Water ◽  
Carbonate Content ◽  
Food Level ◽  
Habitat Segregation ◽  
Species Competition ◽  
Regression Methods ◽  
Number Of Species

To determine whether certain environmental factors may affect standing crop, an analysis was made, primarily by regression methods, of the published estimates of standing crops of fish in lakes and ponds. Standing crop estimates derived by draining and those by poisoning appear to be equally accurate, but marking and recovery estimates may not be directly comparable with the other two. Average standing crops in river backwaters and oxbows were almost 500 pounds per acre; in midwestern reservoirs, almost 400 pounds per acre; in other reservoirs and ponds, 200 to 300; in warm-water lakes, 125 to 150; and in trout lakes, less than 50 pounds per acre.No correlation could be shown between areas of lakes or ponds and their standing crops per acre. There was a tendency for standing crop per acre to decrease with increase in maximum depth of trout lakes, of warm-water lakes, and probably of reservoirs. Significant increase in standing crop per acre with increase in carbonate content of the water was found in trout lakes, warm-water lakes and midwestern reservoirs.Elton's pyramid of numbers was demonstrated in an analysis of standing crop per acre by species. Competition between species at the same food level may be mitigated by habitat segregation. Standing crop per acre increases as the number of species increases or as the niches are filled. However, standing crops of given species were usually highest when only one or two species were present. Regressions of the standing crops of one species upon those of other species may give clues as to the degree of competition or of protocooperation, but these clues must be critically evaluated since the regressions may be due to factors other than the presence of the other species.

Windmill Hill, Avebury, and Grime's Graves Cores and Choppers

1919 ◽  
Vol 3 (1) ◽  
pp. 104-108
Author(s):  
H. G. O. Kendall
Keyword(s):  
The Other ◽  
Light Blue ◽  
Number Of Species ◽  
The One ◽  
Dark Blue

Cores and chopping tools are very numerous at Windmill Hill, Avebury Down, Grime's Graves, and Cissbury. They are characteristic of the industry. In the main they differ markedly from the cores of the prism industries. True prisms are rare in the one and numerous in the other; the one shows comparatively broad, the other comparatively narrow facets and flakes; the flakes of the latter being on the whole thinner and finer. It is noteworthy that when the flints of both industries have lain near the surface, those of the one in Herts., Wilts., Sussex, Norfolk, and Suffolk are almost invariably white or light blue; whilst those of the other range from light blue, through dark blue, to unchanged black or grey; with a partial exception, easy of explanation, on the coast of Cornwall.The “lumps” may be divided into a number of species. Some were cores only, others were tools for chopping, cutting, scraping, pecking, boring, or clearing out split marrow bones; some were cores first and tools afterwards.

scholarly journals Genetic or Psychogenic? A Case Study of “Folie à Quatre” Including Twins

2015 ◽  
Vol 2015 ◽  
pp. 1-3 ◽  
Author(s):  
Tohru Ohnuma ◽  
Heii Arai
Keyword(s):  
Environmental Factors ◽  
Social Isolation ◽  
Schizophrenia Patient ◽  
Monozygotic Twins ◽  
The Other ◽  
Positive Symptoms ◽  
Short Period ◽  
The Common ◽  
Shared Psychotic Disorder

Shared psychotic disorder, characterized by shared delusion among two or more subjects (termed “Folie à deux,” “trois,” etc.), is often associated with strong religious beliefs or social isolation, factors creating strong psychological sympathy. Recently, we treated a rare familial case of “Folie à quatre” in central Tokyo without such influences. The proband was a schizophrenia patient and younger brother within monozygotic twins. Positive symptoms were “transmitted” to remaining family members, his elder brother, mother, and father father, in a relatively short period of three months. Although the pathophysiology of these positive symptoms (delusions and hallucinations) remains unclear, the transmission pattern suggests the primacy of social and environmental factors (and/or their interaction), while genetics appeared less influential in this “Folie à famille.” Although undiagnosed psychoses in the whole family cannot be excluded, they did not share the other negative schizophrenia symptoms of the proband. A strong familial connection appeared to be the most important factor for the common delusion and hallucination.

A Comparative Study of Palmar Dermatoglyphics in Thakurs and Lodhis of Bakshi Ka Talab Lucknow, Uttar Pradesh

2018 ◽  
Vol 2 (01) ◽  
Author(s):  
Preeti Gupta ◽  
Udai Pratap Singh
Keyword(s):  
Environmental Factors ◽  
Comparative Study ◽  
Uttar Pradesh ◽  
White Paper ◽  
The Other ◽  
Main Line ◽  
Males And Females ◽  
Index Value ◽  
Two Populations ◽  
Dermatoglyphic Traits

Dermatoglyphic characters vary widely and are unaffected by age, gender and least by environment. Unlike configurations and their distinctiveness with every individual, it also shows bilateral, bisexual and population variations. Palm prints once created are unchangeable throughout life and are unaffected by environmental factors. This paper is based upon the palmar dermatoglyphic. The study reports on bisexual and bilateral palm prints among Lodhis and Thakurs of Rudahi village of Bakshi Ka Talab, Lucknow District. The palmar dermatoglyphic traits have been analyzed among the two populations which are Main line Formula, Endings of main lines D and A, Position of Axial triradius, Angle atd, Main line Index, Hypothenar, Thenar/ Ist Interdigital area, IInd Interdigital area, IIIrd Interdigital area, IVth Interdigital area, and Palmar Ridge Counts. The prints have been obtained by using the duplicating ink method on white paper. On the perusal of Principal Main line Formula among Lodhis and Thakurs, it has been noticed that the frequency is more in Lodhi males than females in formula 11.9.7. On the other hand, the frequency of Thakur males is more than Thakur females in formula 9.7.5. The Ending of Main Line D in position 11 as clearly indicated in Lodhis is higher in both the genders in comparison to Thakurs, while the position 9 indicates highest frequency in Thakur females. The Ending of main line A at position 5’ has higher frequency in Lodhi males. The Main line index value 16 is observed higher in Lodhis in comparison to Thakurs. Higher frequency has been observed in Lodhis than Thakurs in Axial triradius in modal type‘t’. The range of Angle atd is observed to have higher frequency in 36º- 40º among the Lodhis as compared to Thakurs. The palmar ridge counts mean, is found higher in Lodhi females and Thakur males. Thus this paper shows the similarity and dissimilarity among the males and females of Thakurs and Lodhis in Palmar dermatoglyphics.

Hosts of Amblyomma dissimile Koch, 1844 and Amblyomma rotundatum Koch, 1844 (Acari: Ixodidae)

Zootaxa ◽  
2010 ◽  
Vol 2541 (1) ◽  
pp. 27 ◽  
Author(s):  
ALBERTO A. GUGLIELMONE ◽  
SANTIAGO NAVA
Keyword(s):  
Host Range ◽  
Tick Species ◽  
Wide Distribution ◽  
Trachemys Scripta ◽  
The Other ◽  
Dasypus Novemcinctus ◽  
Number Of Species ◽  
Boa Constrictor ◽  
Hydrochoerus Hydrochaeris ◽  
Natural Hosts

Host records of Amblyomma dissimile Koch, 1844 and Amblyomma rotundatum Koch, 1844 from the literature were critically reviewed. A total of 417 records on 101 species of tetrapods, and 193 records in 74 species of tetrapods were determined for A. dissimile and A. rotundatum, respectively. Aves have been found only once infested with A. dissimile. This tick has been detected on four species of Bufonidae, while A. rotundatum has been recorded on 13 species from six families of Anura. Crocodilia has been recorded infested by A. rotundatum (captive host, one species) and A. dissimile (two species). Sixteen species of Mammalia from ten families and eight species from eight families have been found infested with A. dissimile and A. rotundatum, including humans, respectively. A total of 63 species of Squamata (10 families) were found infested with A. dissimile, while the corresponding numbers for A. rotundatum are 45 species in nine families. A total of 15 species of Testudines (four families) and nine species (three families) have been found infested with A. dissimile and A. rotundatum, respectively. When infestation on captive and laboratory hosts were excluded from the analysis the number of species naturally infested with A. dissimile diminished to 88 and 58 for A. rotundatum. However, natural hosts infested with larvae, nymphs and adults of A. dissimile are Bufo marinus (Linnaeus), Bufo peltocephalus Tschudi, Proechimys semispinosus (Tomes), Boa constrictor Linnaeus, Epicrates striatus (Fischer), Oxybelis aeneus (Wagler), Cyclura cychlura (Cuvier), Iguana iguana (Linnaeus), Tupinambis teguixin (Linnaeus) and Trachemys scripta (Thunberg), but the commonest hosts harbouring all parasitic stages are B. marinus, B. constrictor and I. iguana. Hosts for all parasitic stages of A. rotundatum are B. marinus, Bufo schneideri Werner and B. constrictor, although records on B. marinus are considerably higher than the records on the other two hosts. The contribution of sheep and Hydrochoerus hydrochaeris (Linnaeus) as hosts of A. dissimile, and Dasypus novemcinctus Linnaeus as host of A. rotundatum, were overestimated in previous studies. The ample host-range of these tick species may partly explain their wide distribution from southern U.S.A. to northern Argentina, but there are also chances that more than one species are represented under the names A. dissimile and A. rotundatum.

scholarly journals Skull asymmetries in wild boar (Sus scrofa LINNAEUS, 1758)

2019 ◽  
Vol 56 (1) ◽  
pp. e150704
Author(s):  
Pere M. Parés-Casanova
Keyword(s):  
Environmental Factors ◽  
Wild Boar ◽  
Sus Scrofa ◽  
Age Groups ◽  
The Other ◽  
Directional Asymmetry ◽  
Two Dimensional ◽  
Entire Sample ◽  
Perfect Symmetry ◽  
Left And Right

Organisms can develop different kinds of asymmetry when deviations from expected perfect symmetry occur. Among others are fluctuating asymmetry (FA) and directional asymmetry (DA). FA represents small random differences between corresponding parts on the left and right sides of an individual in bilaterally paired structures. It is thought that FA reflects an organism’s ability to cope with genetic and environmental stress during growth. DA occurs whenever one side on the plane of symmetry develops more than the other side, and has a genetic component. In this research, we examined the expression of morphological symmetry in 38 skulls of different age groups of wild boar (Sus scrofa), on their ventral aspect, using two-dimensional coordinates of 27 landmarks. Analyses showed the presence of significant FA and DA in the entire sample, detecting also distinctive differences between age groups. The obtained results show that the shape differences in different age groups could reasonably be a consequence of a response to environmental factors for FA and a masticatory lateralization for DA.

scholarly journals Milk Production of Lacaune Sheep with Different Degrees of Crossing with Manchega Sheep in a Commercial Flock in Spain

Animals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 520
Author(s):  
Lizbeth E. Robles Jimenez ◽  
Juan C. Angeles Hernandez ◽  
Carlos Palacios ◽  
José A. Abecia ◽  
Anna Naranjo ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Milk Production ◽  
Litter Size ◽  
Milk Yield ◽  
Mixed Model ◽  
The Other ◽  
Commercial Flock ◽  
Parity Number ◽  
Available Information ◽  
Autumn And Winter

The objective of the present study was to evaluate the effect of the grade of crossbreeding (Lacaune x Manchega) and environmental factors on milk production in a commercial flock in Spain. A total of 5769 milk production records of sheep with different degrees of purity of the Lacaune breed crossed with Manchega were used as follows: 100% Lacaune (n = 2960), 7/8 Lacaune (n = 502), 13/16 Lacaune (n = 306), 3/4 (n = 1288), 5/8 Lacaune (n = 441) and 1/2 Lacaune: Manchega (n = 272). Additional available information included the number of parity (1 to 8), litter size (single or multiple), and the season of the year of lambing (spring, summer, autumn and winter). A mixed model was used to evaluate the level of crossbreeding and environmental factors on milk production. The 100% Lacaune sheep presented the highest milk production with respect to the F1 Lacaune x Manchega sheep (p < 0.01), showing that as the degree of gene absorption increases with the Manchega breed, it presents lower milk yield. The 100%, 13/16, and 3/4 Lacaune genotypes had the highest milk yields with respect to the 1/2 Lacaune/Manchega breed (p < 0.001). The Lacaune registered on average 181.1 L in a period adjusted to 160 days of lactation (1.13 L/ day). Likewise, the parity number, litter size, and season of lambing effects showed significant differences (p < 0.01). It was concluded that 13/16 and 3/4 Lacaune/Manchega ewes presented the highest milk yields with respect to the other crosses.

Exploring SMEs Adoption of Broadband in the Northwest of England

2011 ◽  
pp. 504-523 ◽  
Author(s):  
Boumediene Ramdani ◽  
Peter Kawalek
Keyword(s):  
Environmental Factors ◽  
Information And Communication Technologies ◽  
Communication Technologies ◽  
Decision Makers ◽  
The Other ◽  
Policy Makers ◽  
Information And Communication ◽  
Adoption Model

This chapter explores the factors impacting small to medium-sized enterprises’ (SMEs) adoption of broadband. It argues that information and communication technologies (ICTs) are highly differentiated technologies for which there is not necessarily a single adoption model. While most large European companies are connected to broadband, SMEs’ connectivity is lagging behind. The question of why one SME adopts broadband while the other does not is still understudied. Therefore, the purpose of this chapter is to fill this gap by investigating the technological, organizational, and environmental factors impacting SMEs’ adoption of broadband. This chapter starts by highlighting the importance of ICT innovations adoption in general and broadband in particular. Based on the ICT innovations adoption literature, SMEs’ broadband adoption framework will be developed and empirically validated involving nine SMEs’ key decision makers in the northwest of England. Finally, implications for researchers, practitioners, ICTs’ vendors, and policy makers will be discussed.

A Dynamic Conceptual Framework of Generalized Adaptation to Stressful Stimuli

1976 ◽  
Vol 38 (1) ◽  
pp. 319-334 ◽  
Author(s):  
Bradford S. Wild ◽  
Carolyn Hanes
Keyword(s):  
Environmental Factors ◽  
Conceptual Framework ◽  
Adaptive Behavior ◽  
Dynamic Process ◽  
Empirical Investigation ◽  
The Other ◽  
Adaptation To Stress ◽  
Parallel Processes ◽  
Environmental Demands

This paper reviews the currently popular definitions and theoretical arguments of the so-called “stress” perspective with the purpose of integrating this material into one general paradigm. The literature has been concerned primarily with two parallel processes which purport to account for the individual's coping and adaptive behavior, one characterized by the interplay of internal, psychological forces, and the other by external, environmental factors. These two general processes have been integrated in this paper by expanding upon the general models presented by Dohrenwend (7) to include important feedback processes. It is argued that adaptation to stress is a dynamic process and that the failure to adapt is often the result of a continuing process of past failures by the organism effectively to cope with less severe stressful stimuli, each failure feeding back to affect future attempts to cope with new environmental demands. The implications of the approach presented in this paper for future empirical investigation are discussed.

scholarly journals Sexual dimorphism in species of Schistura (Teleostei: Nemacheilidae) from the Mae Khlong basin and peninsular Thailand

Zootaxa ◽  
2012 ◽  
Vol 3586 (1) ◽  
pp. 353 ◽  
Author(s):  
RUNGTHIP PLONGSESTHEE ◽  
F. WILLIAM H. BEAMISH ◽  
LAWRENCE M. PAGE
Keyword(s):  
Sexual Dimorphism ◽  
Environmental Factors ◽  
The Other ◽  
Sexually Dimorphic ◽  
Morphometric Characteristics ◽  
Pectoral Fin ◽  
Caudal Fin

Sexually dimorphic characteristics are described for four species of Schistura from the Mae Khlong basin and peninsularThailand. Males of S. mahnerti have a suborbital flap and rows of unculi on the upper surfaces of the pectoral-fin rays.Females of S. mahnerti have a suborbital groove. None of the morphological measurements differ significantly betweenmales and females of S. mahnerti. In the other three species, S. aurantiaca, S. cf. aurantiaca, and S. sexcauda, all indi-viduals lack the flap or groove, but most males have a conspicuous black botch on the procurrent rays of the upper lobeof the caudal fin, a feature absent in most females. Some morphometric characteristics vary between sexes of these spe-cies. Sexually dimorphic traits presumably have a function related to reproduction; however, little is known about reproduction in Schistura, and variation in morphology in relation to habitat or other environmental factors has not been studied.

scholarly journals Effect of Sodium Carbonate Concentration in Calgon on Hydrometer Analysis Results

2018 ◽  
Author(s):  
Arshdeep Kaur ◽  
George C. Fanourakis
Keyword(s):  
Sodium Carbonate ◽  
Clay Content ◽  
The Other ◽  
Sodium Hexametaphosphate ◽  
Carbonate Content ◽  
Fine Grained ◽  
Carbonate Concentration ◽  
Dispersing Agent ◽  
Effective Combination ◽  
Dispersing Agents

Calgon (a combination of sodium hexametaphosphate and sodium carbonate) has proved to be the most effective dispersing agent in determining the grain size distribution of fine-grained soils by means of the hydrometer analysis. Previous research on the effect of the sodium hexametaphosphate content of dispersing agents on the clay contents showed that the addition of sodium carbonate to sodium hexametaphosphate increases its dispersing effectiveness. Hence, Calgon 35:7 was used /recommended by many researchers/methods and proved to be the most effective dispersing agent. Although previous work focusing on the effect of varying the concentration of sodium hexametaphosphate in Calgon has been reported, the effect of the concentration of sodium carbonate in Calgon has not been assessed and reported. For this reason, in this investigation a series of hydrometer test analyses were conducted using the 152H and ASTM 152H: E100 hydrometers with Calgon in ratios of 35:0, 35:20 and 35:30.  It was observed that with any increase in sodium carbonate content beyond 7 grams, the percentage clay content actually decreased tremendously in the case of hydrometer 152H. However, for the other hydrometer, Calgon (35:0) proved to be most effective combination. Thus, the increase in the sodium carbonate content in Calgon, beyond 7 g/ litre, is not recommended.

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