scholarly journals Gill Movements of Nymphal Ephemera danica (Ephemeroptera) and the Water Currents caused by them

1939 ◽  
Vol 16 (1) ◽  
pp. 18-33 ◽  
Author(s):  
L. E. S. EASTHAM
Keyword(s):  
Transverse Force ◽  
The Body ◽  
Body Axis ◽  
Angle Of Incidence ◽  
Middle Line ◽  
Water Currents ◽  
The Difference ◽  
Force Components ◽  
Set Up ◽  
Ephemera Danica

1. The six pairs of gills in Ephemera danica causing currents in the water are bilamellate and feather-like. 2. The gills move in metachronal rhythm from before backwards, and set up currents which are symmetrical with the body axis. Members of pairs of gills beat synchronously and in phase with each other. The difference of phase between two adjacent gills of the same side is about one-eighth of a complete oscillation. 3. For a single gill there is little or no difference in the angle presented by the gill to its own path of motion, in the two halves of an oscillation. This factor (angle of incidence) is not of great importance in directing water backwards. Forces of importance in moving water in the direction taken are (i) the resultant of axial and transverse force components for single gills, (ii) the pressure effected on the water over the animal's back by the two members of a pair of gills falling, (iii) the movement backwards of alternating pressure regions over the back, (iv) the undulations of the second screw-like gills which feed the main current from in front and from the sides. 4. The fringing filaments of adjacent gills overlap each other from before backwards (as seen from the middle line of the body), and thus each row of gills forms a "membrane" composed of separate gill units. The latter appear never to lose contact with each other during movement, and since no sideways flow is observed between the gills it is assumed that the overlapping filaments between the gills form a membrane impermeable to flow. 5. The adaptation of Ephemera to its sandy environment is shortly discussed.

The Body Temperature of Tenebrionid Beetles in the Namib Desert of Southern Africa

1971 ◽  
Vol 55 (1) ◽  
pp. 253-272
Author(s):  
E. B. EDNEY
Keyword(s):  
Heat Balance ◽  
Muscular Activity ◽  
Selective Advantage ◽  
Short Wave ◽  
The Body ◽  
Wave Radiation ◽  
Consistent Difference ◽  
Angle Of Incidence ◽  
Lethal Temperatures ◽  
The Difference

1. In direct sunshine the abdomen of living Onymacris brincki, which is covered by white elytra, was 3-4 °C cooler than its thorax, while in the same conditions the abdomen and thorax of O. rugatipemtis, which is an entirely black beetle, had the same temperature. Since similar effects were observed in dead beetles, the warmer thorax was not due to muscular activity. When the white elytra of brincki were covered with carbon black, its abdominal temperature rose to equal that of rugatipenntis. Models, made of pieces of black and white elytra, showed similar effects. 2. The smaller species Stenocara eburnea (with white elytra) showed a smaller and less consistent temperature depression when compared with the similar-sized species S. depressa (which is black). Abdomens of O. rugatipennis, O. laeviceps and Physosterna cribripes (all large black beetles) were from 3-5 °C wanner than O. brincki, but showed no consistent difference among themselves. 3. When O. rugatipennis was oriented head-on to the sun in its natural environment its thorax was about 4 °C cooler than when its long axis was normal to the sun's rays. Beetles exposed to sunshine were 12-15 °C warmer than they were in the shade. When transferred from one to the other, the greater part of temperature equilibration occurred in about 2 min and equilibration was complete in about 4 min. 4. Observation suggested that beetles thermoregulate by moving between sunshine and shade. Measurements showed that a beetle exposed to alternating periods of 10 sec in sunshine and 30 sec in shade reached a steady temperature of about 33 °C, while the reverse conditions (10 sec in the shade and 30 sec in sunshine) led to a temperature of about 38 °C. In continuous alternations thoracic temperatures remained constant within about 1 °C. 5. Laboratory experiments in which the angle of incidence of the sun's rays was varied through 180° confirmed the field results and showed that white elytra lower the abdominal temperature of living and dead beetles. 6. Upper lethal temperatures for 30 min in saturated air varied from 50 °C for the desert tenebrionid Onymacris plana to 42.5 °C for the mesic species Trigonopus capicola. In general, upper lethal temperatures correlated well with habitat and habit. 7. Making certain assumptions, analysis of the heat balance of beetles during one exposure in sunshine suggests that the difference between the white elytra of brincki and the black ones of rugatipennis as regards the amount of short-wave radiation reflected is 0.227 cal cm-2 min-1, and further, that the reflectivities of the two surfaces are 79% and 38% respectively. 8. The selective advantage of white elytra probably has little to do with heat balance; the vivid contrast between white and black suggests that the pattern may be aposematic.

Flagellar movement of the Sessile Flagellates Actinomonas, Codonosiga, Monas, and Poteriodendron

1964 ◽  
Vol s3-105 (72) ◽  
pp. 405-414
Author(s):  
M. A. SLEIGH
Keyword(s):  
Water Flow ◽  
Current Flow ◽  
The Body ◽  
The Other ◽  
Water Currents ◽  
Different Types ◽  
Food Particles ◽  
Wave Range ◽  
Set Up ◽  
Contraction Wave

Water currents set up by flagellar activity are used to bring food particles to the body in each of the sessile flagellates Actinomonas, Codonosiga, Monas, and Poteriodendron. The water currents produced by the 4 organisms are all somewhat different, and, while that set up by Codonosiga is in the expected direction with water flow from the flagellar base towards the tip, the currents set up by the other 3 forms flow from the tip towards the base. In all 4 types the flagellar movements take the form of plane sinusoidal undulations propagated from the base of the flagellum towards its tip, but the different types show adaptive modifications according to the pattern of water currents required. The rates of beat of the flagellum (range 30 to 50 cycles/ sec) and the speeds of propagation of the contraction wave (range 100 to 600 µ/sec) did not differ sufficiently to explain different current patterns. It is suggested that the ‘unexpected’ direction of current flow in 3 of the types may be the result of the presence of flagellar mastigonemes; these are known to be present in the chrysomonad phytoflagellates, to which group Monas and probably also Actinomonas and Poteriodendron belong. Attention is also drawn to the peculiar mode of coiling and unrolling of the flagellum of the bicoecid Poteriodendron.

Adjustment of basking postures in the high-altitude Iberian rock lizard (Lacerta monticola)

1995 ◽  
Vol 73 (6) ◽  
pp. 1065-1068 ◽  
Author(s):  
Jose Martín ◽  
Pilar López ◽  
Luis M. Carrascal ◽  
Alfredo Salvador
Keyword(s):  
Body Size ◽  
Early Morning ◽  
The Body ◽  
Body Axis ◽  
Angle Of Incidence ◽  
The Sun ◽  
Dorsal Part ◽  
Heating Rates ◽  
Compass Orientation ◽  
Rock Lizard

We studied the relationships between thermoregulatory basking postures and heating rates in the Iberian rock lizard (Lacerta monticola). Heating rates were high when body size was small, the substrate temperature was high, and the angle of incidence of the sun's rays was high (i.e., the rays were perpendicular to the lizard's body). However, heating rates were not related to the compass orientation of lizard's body axis to the sun (perpendicular versus in line with the sun). In the field, the slopes of the body axis of basking individuals were higher during the early morning. However, neither the cardinal orientation of a lizard's body axis to the sun nor the frequency of flattening varied during the morning. Postural adjustments to select an adequate angle of incidence of the sun's rays on the dorsal part of the body suggest that this behaviour might enhance absorption of solar radiation.

Emotions: How Many Are There?

2012 ◽  
Author(s):  
Jesse J. Prinz
Keyword(s):  
Semantic Content ◽  
Well Being ◽  
The Body ◽  
Appraisal Theory ◽  
The Creation ◽  
The Difference ◽  
Set Up

This article focuses on a particular theory of the emotions, somatic appraisal theory, which explain the range of emotions effectively. The somatic appraisal theory is designed to compensate for the flaw in James's formulation according to which emotions are perceptions of patterned changes in the body. James's theory does not capture the idea that emotions are meaningful. Somatic appraisal theory mentions that emotions are perceptions of changes in the body and also carry information about circumstances that bear on well-being. The bodily changes that occur and the perception thereof have the function of carrying information about loss. They were set up as responses to loss. Somatic appraisal theory has much in common with Ekman's Darwinean modules. Ekman states that each emotion is associated with a physiological pattern. Ekman mentions that the patterns are evolved adaptations, and that is also true in somatic appraisal theory. He also says that emotions exploit automatic appraisals. Ekman mentions that appraisals are components of emotions, while somatic appraisal theory reports that they are causes, rather than components, but the difference is not especially important for present purposes. Somatic appraisal theory is compatible with three ways of acquiring new emotions. Emotions are individuated by their semantic content and their somatic profile (the pattern of bodily changes the perception of which constitutes the emotion). A change in semantic content could lead to the creation of a new emotion, and the introduction of new bodily patterns could as well.

scholarly journals THE GILL MOVEMENTS OF NYMPHAL ECDYONURUS VENOSUS (EPHEMEROPTERA) AND THE CURRENTS PRODUCED BY THEM IN WATER

1937 ◽  
Vol 14 (2) ◽  
pp. 219-228 ◽  
Author(s):  
L. E. S. EASTHAM
Keyword(s):  
Environmental Flow ◽  
The Body ◽  
Angle Of Incidence ◽  
Sense Organs ◽  
Anterior Border ◽  
Compression Phase ◽  
Recovery Movement ◽  
Leading Position ◽  
Effective Part ◽  
Set Up

1. The gills of the nymph of Ecdyonurus consist each of a gill plate and a proximal gill tuft. The gill plate of the first gill is reduced in size while the seventh gill possesses no gill tuft. 2. By movements of the gills, currents are set up in the water which are symmetrical with the body axis, and which pass from the sides of the body upwards to the mid-dorsal line and backwards. Members of pairs beat synchronously and in phase with each other. 3. Each gill pivots on its pedicel and moving backwards and upwards, increases its angle of incidence with the water through which it passes. This phase is the effective part of an oscillation and is brought about with the posterior gill surface in the leading position. The recovery beat is effected by the gill turning so as to place the anterior border in a leading position. The direction of flow is largely determined by these gill movements. 4. The gills beat in metachronal rhythm from before backwards, the time phase difference between adjacent gills being so small as to make the gills appear to work together and without rhythm. The rhythm, however, is important in setting up suction and compression phases, the compression phase occurring during backward effective movement, the suction during forward recovery movement. Compression expresses itself as a flow from between the gills upwards and backwards, suction as a flow into the intergill space from the sides and below. 5. The principles of gill movement in relation to water flow in Caenis, Leptophlebia and Ecdyonurus are compared. 6. The currents and gill movements in adaptation to environment are briefly discussed. 7. Campaniform sense organs occur on both surfaces of the gill plates and it is suggested that these are concerned with informing the animal of changes in the environmental flow of water.

Our Bodies, Whose Property?

2013 ◽  
Author(s):  
Anne Phillips
Keyword(s):  
Labor Markets ◽  
Personal Autonomy ◽  
The Body ◽  
Body Parts ◽  
Complex Issue ◽  
Human Organs ◽  
Property Owners ◽  
The Common ◽  
The Difference ◽  
The Right

No one wants to be treated like an object, regarded as an item of property, or put up for sale. Yet many people frame personal autonomy in terms of self-ownership, representing themselves as property owners with the right to do as they wish with their bodies. Others do not use the language of property, but are similarly insistent on the rights of free individuals to decide for themselves whether to engage in commercial transactions for sex, reproduction, or organ sales. Drawing on analyses of rape, surrogacy, and markets in human organs, this book challenges notions of freedom based on ownership of our bodies and argues against the normalization of markets in bodily services and parts. The book explores the risks associated with metaphors of property and the reasons why the commodification of the body remains problematic. The book asks what is wrong with thinking of oneself as the owner of one's body? What is wrong with making our bodies available for rent or sale? What, if anything, is the difference between markets in sex, reproduction, or human body parts, and the other markets we commonly applaud? The book contends that body markets occupy the outer edges of a continuum that is, in some way, a feature of all labor markets. But it also emphasizes that we all have bodies, and considers the implications of this otherwise banal fact for equality. Bodies remind us of shared vulnerability, alerting us to the common experience of living as embodied beings in the same world. Examining the complex issue of body exceptionalism, the book demonstrates that treating the body as property makes human equality harder to comprehend.

Theory-Practice Gap: The Experiences of Nigerian Nursing Students

2018 ◽  
Vol 20 (1) ◽  
Author(s):  
Titilayo Dorothy Odetola ◽  
Olusola Oluwasola ◽  
Christoph Pimmer ◽  
Oluwafemi Dipeolu ◽  
Samson Oluwayemi Akande ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Nursing Students ◽  
Developing Country ◽  
The Body ◽  
Clinical Staff ◽  
Clinical Settings ◽  
Practice Gap ◽  
The Difference ◽  
Analyse Data ◽  
Theory Practice Gap

The “disconnect” between the body of knowledge acquired in classroom settings and the application of this knowledge in clinical practice is one of the main reasons for professional fear, anxiety and feelings of incompetence among freshly graduated nurses. While the phenomenon of the theory-to-practice gap has been researched quite extensively in high-income country settings much less is known about nursing students’ experiences in a developing country context. To rectify this shortcoming, the qualitative study investigated the experiences of nursing students in their attempt to apply what they learn in classrooms in clinical learning contexts in seven sites in Nigeria. Thematic content analysis was used to analyse data gained from eight focus group discussions (n = 80) with the students. The findings reveal a multifaceted theory-practice gap which plays out along four tensions: (1) procedural, i.e. the difference between practices from education institutions and the ones enacted in clinical wards – and contradictions that emerge even within one clinical setting; (2) political, i.e. conflicts that arise between students and clinical staff, especially personnel with a lower qualification profile than the degree that students pursue; (3) material, i.e. the disconnect between contemporary instruments and equipment available in schools and the lack thereof in clinical settings; and (4) temporal, i.e. restricted opportunities for supervised practice owing to time constraints in clinical settings in which education tends to be undervalued. Many of these aspects are linked to and aggravated by infrastructural limitations, which are typical for the setting of a developing country. Nursing students need to be prepared regarding how to deal with the identified procedural, political, material and temporal tensions before and while being immersed in clinical practice, and, in so doing, they need to be supported by educationally better qualified clinical staff.

Perbedaan Penggunaan Antikoagulan K2EDTA DAN K3EDTA Terhadap Hasil Pemeriksaan Indeks Eritrosit

2018 ◽  
Vol 1 (2) ◽  
pp. 114
Author(s):  
Wahdaniah Wahdaniah ◽  
Sri Tumpuk
Keyword(s):  
Screening Test ◽  
Venous Blood ◽  
The Body ◽  
Ethylene Diamine ◽  
P Value ◽  
Cross Sectional ◽  
Significant Difference ◽  
Ethylene Diamine Tetra Acetate ◽  
The Difference ◽  
Index Value

Abstract: Routine blood examination is the earliest blood test or screening test to determine the diagnosis of an abnormality. Blood easily froze if it is outside the body and can be prevented by the addition of anticoagulants, one of which Ethylene Diamine Tetra Acetate (EDTA). Currently available vacuum tubes containing EDTA anticoagulants in the form of K2EDTA and K3EDTA. K3EDTA is usually a salt that has better stability than other EDTA salts because it shows a pH approaching a blood pH of about 6.4. The purpose of this research is to know the difference of erythrocyte index results include MCH, MCV and MCHC using K3EDTA anticoagulant with K2EDTA. This research is a cross sectional design. This study used venous blood samples mixed with K2EDTA anticoagulant and venous blood mixed with K3EDTA anticoagulants, each of 30 samples. Data were collected and analyzed using paired different test. Based on data analysis that has been done on MCH examination, p value <0,05 then there is a significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value. Then on the examination of MCV and MCHC obtained p value <0.05 then there is no significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value.Abstrak: Pemeriksaan darah rutin merupakan pemeriksaan darah yang paling awal atau screening test untuk mengetahui diagnosis suatu kelainan. Darah mudah membeku jika berada diluar tubuh dan bisa dicegah dengan penambahan antikoagulan, salah satunya Ethylene Diamine Tetra Acetate (EDTA). Dewasa ini telah tersedia tabung vakum yang sudah berisi antikoagulan EDTA dalam bentuk  K2EDTA dan  K3EDTA. K3EDTA  biasanya berupa garam yang mempunyai stabilitas yang lebih baik dari garam EDTA yang lain karena menunjukkan pH yang mendekati pH darah yaitu sekitar 6,4. Tujuan dari penelitian ini adalah untuk mengetahui perbedaan hasil indeks eritrosit meliputi MCH, MCV dan MCHC menggunakan antikoagulan K3EDTA dengan K2EDTA. Penelitian ini merupakan penelitian dengan desain cross sectional. Penelitian ini menggunakan sampel darah vena yang dicampur dengan antikoagulan K2EDTA dan darah vena yang dicampur dengan antikoagulan K3EDTA, masing-masing sebanyak 30 sampel. Data dikumpulkan dan dianalisis menggunakan uji beda berpasangan. Berdasarkan analisis data yang telah dilakukan pada pemeriksaan MCH didapatkan nilai p < 0,05 maka ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit. Kemudian pada pemeriksaan MCV dan MCHC didapatkan nilai p < 0,05 maka tidak ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit.

Effect of Sample Storage Conditions on Body Burden Analysis of Organic Contaminants in Unionid Mussels

1992 ◽  
Vol 27 (4) ◽  
pp. 833-844 ◽  
Author(s):  
Micheline Hanna
Keyword(s):  
Organic Contaminants ◽  
Body Burden ◽  
Storage Conditions ◽  
The Body ◽  
Sample Storage ◽  
Pcb Congeners ◽  
Unionid Mussels ◽  
Group A ◽  
The Difference ◽  
Group B

Abstract In order to quantitatively assess the effect of sample storage conditions on the body burden analysis of organic contaminants, a comparative analysis was carried out on the unionid mussel Elliptic complanata. The mussels were divided into two groups, each with distinct storage conditions, while Group A was kept in the freezer at −20°C, Group B was kept in the refrigerator for five days at 5°C. All the compounds present in the control were also present in Group B samples. Analysis of the organic contaminants in each of these two groups showed that for total PCB concentrations, the two treatments were not significantly different; however when compared individually 6 of the 13 PCB congeners showed significant differences. The observed differences were relatively small for individual PCB congeners (7.1 to 15.3%), higher for chlorobenzenes (10.5 to 36.4%), and yet higher for HCE (44.1%); the difference for HCE, although large is nevertheless not significant, even if only marginally so.

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