Memoirs: On the Intracellular Micro-organisms of some Bostrychild Beetles

1934 ◽  
Vol s2-77 (306) ◽  
pp. 243-253
Author(s):  
K. MANSOUR
Keyword(s):  
Alimentary Tract ◽  
Posterior Pole ◽  
Bursa Copulatrix ◽  
Final Destination ◽  
Rhizopertha Dominica ◽  
Pass Through ◽  
Micro Organisms ◽  
Biological Relation

1. Rhizopertha dominica, F., Sinoxylon ceratoniae, L., and Bostrychoplites Zickeli, Mars., possess paired mycetomes full of bacteria-like micro-organisms. 2. The transmission of the micro-organisms from one generation of the host to the next is carried out in the following way: (a) Micro-organisms from the mycetomes invade the testis lobes, multiply, and mix with the sperms. (b) These micro-organisms pass with the sperms during copulation into the bursa copulatrix of the female. (c) From this region they pass through the micropyle of the fully formed eggs during their passage to the outside, and thus the infection is accomplished. 3. The invasion of the testis lobes by micro-organisms causes abnormality in the process of spermatogenesis. 4. The micro-organisms in the developing egg are first seen near the micropylar region in the peripheral protoplasm. In a later stage these micro-organisms, which have multiplied greatly by then, are to be found in between the yolk globules towards the posterior pole of the egg. From this stage onwards the course these micro-organisms follow till they reach their final destination in the larva has not been followed. 5. The mycetomes throughout life remain quite isolated from the alimentary tract. 6. The biological relation between the micro-organisms and their host is also discussed.

scholarly journals Challenges in managing a large metallic Foreign Body in Oropharynx of a child: A case report

2021 ◽  
Author(s):  
Manisha Paneru ◽  
Ajit Nepal ◽  
Binam Ghimire
Keyword(s):  
Case Report ◽  
Foreign Body ◽  
Alimentary Tract ◽  
Pediatric Population ◽  
Metallic Foreign Body ◽  
Common Condition ◽  
Key Factors ◽  
Surgical Interventions ◽  
Pass Through

Foreign Body (FB) ingestion is common condition in pediatric population .Curious nature and tendency to put objects in mouth are the key factors for its higher prevalence among them. Most of the ingested FB pass through the entire alimentary tract uneventful, however some require surgical interventions for its removal.

COMPARISON OF FEED WITHDRAWAL TIME AND PASSAGE OF GUT CONTENTS IN BROILER CHICKENS HELD IN CRATES OR LITTER PENS

1979 ◽  
Vol 59 (1) ◽  
pp. 63-66 ◽  
Author(s):  
J. D. SUMMERS ◽  
S. LEESON
Keyword(s):  
Water Uptake ◽  
Broiler Chickens ◽  
Alimentary Tract ◽  
Gut Contents ◽  
Withdrawal Time ◽  
Running Water ◽  
Feed Withdrawal ◽  
Access To Water ◽  
Ad Libitum ◽  
Pass Through

In two experiments, individually weighed male broiler chickens were held without feed in either conventional transporting crates or litter floor pens. These latter birds received water ad libitum and were given constant light. At regular intervals, 12 of the crated or 10 of the penned birds were killed and the section of the proximal alimentary tract containing feed residue recorded. Carcass yield and water uptake after 2 h immersion in running water at 4 °C was also recorded. Feed residue did not pass through the tract of birds held in crates, since approximately 70% of these birds had feed in their gizzard after 16 h. Holding in pens resulted in a progressive emptying of the gut, such that after 12 h the upper tract was evacuated. Less shrink was observed for birds held in pens, which might be explained by the birds having access to water. It is concluded that the alimentary tract of birds cannot effectively be cleared of feed when birds are held in crates. Thus the time birds spend in transport should not be included in calculating time of feed withdrawal.

A Model of Pattern Formation in Insect Embryogenesis

1977 ◽  
Vol 23 (1) ◽  
pp. 117-139
Author(s):  
H. MEINHARDT
Keyword(s):  
Positional Information ◽  
Posterior Pole ◽  
Morphogen Gradient ◽  
Insect Development ◽  
High Concentration ◽  
Insect Embryogenesis ◽  
Anterior Side ◽  
First Pass ◽  
Pass Through ◽  
The Individual

A model is proposed in which the interaction of an autocatalytic substance with a short diffusion range - the activator - and its more diffusible antagonist - the inhibitor - leads to a local high concentration of activator at the posterior pole of the egg. The inhibitor, which is then produced mainly in this activated region, diffuses into the rest of the egg, where it acts as a ‘morphogen’, forming a concentration gradient which supplies positional information. This model can account quantitatively for the patterns resulting from a large number of different experiments performed during early insect development, including ligation, u.v.-irradiation and microsurgical manipulations. The formation of additional posterior structures is interpreted as the result of the appearance of a new activator peak. Omission of segments after ligation of the egg is explained as the result of accumulation of morphogen (the inhibitor) at the posterior side of the ligation and a decrease of morphogen on the anterior side. In order to account for certain quantitative features of the ligation experiments it is necessary to assume that determination in response to the morphogen gradient is a slow, stepwise process, in which the nuclei or cells first pass through determination stages characteristic for more anterior structures until they ultimately form a given structure. The mutual interactions of activator and inhibitor are expressed as a set of partial differential equations. The individual experiments are simulated by solving these equations by use of a computer.

Patency and transmission of Filaroides hirthi infection

Parasitology ◽  
1977 ◽  
Vol 75 (2) ◽  
pp. 251-257 ◽  
Author(s):  
J. R. Georgi ◽  
M. E. Georgi ◽  
D. J. Cleveland
Keyword(s):  
Lung Tissue ◽  
Zinc Sulphate ◽  
Alimentary Tract ◽  
The Body ◽  
Low Grade ◽  
Single Exposure ◽  
Faecal Contamination ◽  
Baermann Technique ◽  
Mesenteric Lymph ◽  
Pass Through

Filaroides hirthi lungworm infection was diagnosed by the recovery of 1st-stage larvae from the faeces of dogs with heavy, artificially induced infections using zinc sulphate flotation. Diagnosis of low-grade natural infections was infrequently achieved. Zinc sulphate flotation was demonstrated to be about 100 times as efficient as the Baermann technique in concentrating F. hirthi larvae from dog faeces. Larvae recovered from faeces proved to be infective when fed to a pup and it was concluded that F. hirthi infection can be transmitted directly and immediately by fresh faecal contamination. Mongrel dogs of diverse ancestry were readily infected by feeding 1st-stage larvae from lung tissue. This, F. hirthi infection was shown not to be limited to the Beagle breed by biological restrictions. The observations that 1st-stage larvae pass through the alimentary tract on their way out of the body and that larvae are found in the mesenteric lymph modes long after a single exposure to infection support the hypothesis that there is an autogenous re-infection of the host by a proportion of these larvae.

Microstructure Motivated Growth and Remodeling of the Lamina Cribrosa in Early Glaucoma

2011 ◽  
Author(s):  
Rafael Grytz ◽  
Ian A. Sigal ◽  
Jeffrey W. Ruberti ◽  
J. Crawford Downs
Keyword(s):  
Connective Tissue ◽  
Structural Changes ◽  
Lamina Cribrosa ◽  
Posterior Pole ◽  
Retinal Ganglion ◽  
Experimental Glaucoma ◽  
Relevant Risk Factor ◽  
Orbital Space ◽  
Iop Elevation ◽  
Pass Through

Glaucoma is a leading cause of blindness in the world and is due to the loss of retinal ganglion cell axons. These axons deteriorate in a region in the posterior pole of the eye known as the optic nerve head (ONH). The axons pass through the lamina cribrosa (LC) as they exit the eye at the ONH. The LC is characterized by a porous, connective tissue structure composed of laminar beams. The function of the LC is unclear, but is believed to include providing mechanical support to the axons as they transition from inside the pressurized globe to the lower pressure orbital space. Early experimental glaucoma studies have shown that the LC remodels into a thicker, more posterior structure which incorporates more connective tissue after chronic IOP elevation [1,2]. The process by which this occurs is unknown. These structural changes are assumed to play an important role in the pathophysiology of the ocular disease glaucoma, where elevated IOP is known to be the most relevant risk factor.

Biomechanics of the Posterior Pole During the Remodeling Progression From Normal to Early Experimental Glaucoma

2009 ◽  
Author(s):  
Ian A. Sigal ◽  
Hongli Yang ◽  
Michael D. Roberts ◽  
Claude F. Burgoyne ◽  
J. Crawford Downs
Keyword(s):  
Visual Information ◽  
Lamina Cribrosa ◽  
Posterior Pole ◽  
Glaucomatous Optic Neuropathy ◽  
Retinal Ganglion ◽  
Experimental Glaucoma ◽  
Pass Through ◽  
Mechanical Insult ◽  
The Brain ◽  
Connective Tissue Structure

Glaucoma is one of the leading causes of blindness worldwide. The loss of vision associated with glaucoma is due to damage to the retinal ganglion cell axons, which transmit visual information to the brain. Damage to these axons is believed to occur as the axons pass through the lamina cribrosa (LC), a connective tissue structure in the optic nerve head at the back of the eye. Elevated intraocular pressure (IOP) has been identified as the main risk factor for the development of the neuropathy, but the mechanism(s) by which a mechanical insult (elevated IOP) is translated into a biological effect (glaucomatous optic neuropathy) is not well understood.

scholarly journals Notes on Certain Aspects of the Biology of Cumopsis Goodsiri (Van Beneden) and Some Other Cumaceans in Relation to their Environment

1944 ◽  
Vol 26 (1) ◽  
pp. 61-71 ◽  
Author(s):  
Audrey Y. Dixon
Keyword(s):  
Rough Surface ◽  
Close Association ◽  
Suspended Particles ◽  
The Body ◽  
Adult Males ◽  
The Third ◽  
Gill Chamber ◽  
Pass Through ◽  
Sandy Substratum ◽  
Micro Organisms

The breathing, feeding, swimming, burrowing and cleaning habits of Cumopsis goodsiri are discussed.Cumopsis has compact respiratory chambers. The inspiratory current enters each gill chamber posteriorly at the base of the third maxillipede, and the expiratory current leaves anteriorly through the siphons which pass through the pseudorostral chamber. The inspiratory current is filtered from all suspended particles by a sieve placed at the mouth of the respiratory funnel, which is formed by the depression of the third maxillipede away from the body. The size of the spaces in the mesh of this sieve probably determines the grade of the substratum in which the animal can live.Cumopsis feeds on micro-organisms which it cleans off sand grains and other small objects. These are collected by the first peraeopods, held in position by the third maxillipedes, and cleaned by the first and second maxillipedes. The food is then passed on to the maxillae, maxillules and mandibles and finally enters the mouth. All these appendages are suitably armed to perform their respective functions.Use is made of the last four pairs of peraeopods in burrowing and Cumopsis will only burrow into a sandy substratum. Swimming is accomplished in three different ways: (a) by flexures of the abdomen, (b) by paddle-like movements of the exopodite of the first peraeopod, and (c) in adult males by the abdominal pleopods.The body is cleaned by the uropods. Their general rough surface and flexibility is very important. The uropod armature seems to add efficiency to the cleaning movements in the adult animals, particularly in the males.The size of the soil particle is vitally important in the distribution of the Cumacea. It determines whether the animals breathe properly. There is also probably a close association between the soil grade and distribution of soil micro-organisms upon which they feed. As a result they refuse to burrow into a soil grade which is unfavourable.

scholarly journals Dance Studies in the International Academy: Genealogy of a Disciplinary Formation

2009 ◽  
Vol 41 (1) ◽  
pp. 23-44 ◽  
Author(s):  
Jens Richard Giersdorf
Keyword(s):  
New York ◽  
Art History ◽  
Home Country ◽  
The United States ◽  
Dance Studies ◽  
Final Destination ◽  
The Past ◽  
Pass Through ◽  
The Moment ◽  
International Academy

For the past thirteen years, I have been traveling to the United States from my home country of Germany, first as a graduate student in California and later as a professor living in New York. Every time I pass through immigration, I am asked a series of questions regarding my final destination and my occupation. The latter always leads to some confusion, because when I am asked what I do, my accent seems to turn “dance history” into “dentistry.” Forced by phonetics to use the term “dance studies,” when confronted by the blank face of the customs officer, I inevitably embark on an explanation of what “dance studies” might be. Just in the moment when I finally see some comprehension of my profession lighting up the officer's face, the question is asked: “And we pay you to do this?”I constantly find myself in the position of having to explain my work. Usually I avoid a long-winded, defensive justification by comparing dance studies to one of its neighboring disciplines: “It is like art history, just writing about dance instead of paintings.” That usually does the trick, but it leaves a foul taste in my mouth. I know that dance studies isn't like art history and I certainly don't want it to be.

scholarly journals Production, absorption, distribution and excretion of vitamin B12 in sheep

1970 ◽  
Vol 24 (4) ◽  
pp. 857-877 ◽  
Author(s):  
R. M. Smith ◽  
Late H. R. Marston
Keyword(s):  
Small Intestine ◽  
Urinary Excretion ◽  
Alimentary Tract ◽  
Basal Diet ◽  
Dry Weight ◽  
Particulate Material ◽  
Vitamin B ◽  
Deficient Diet ◽  
Faecal Excretion ◽  
Micro Organisms

1. The efficiency of production and utilization of vitamin B12 was studied with sheep given a cobalt-deficient diet with and without supplementary Co (1 mg/d). Vitamin B12 to lignin ratios in rumen contents were used to estimate minimum rates of production and these were related to faecal and urinary excretion. Tissue distribution and excretion of vitamin B12 were studied with [58Co]cyanocobalamin and 5′-deoxyadenosyl[60Co]cobalamin.2. Labelled Co was rapidly sequestered by particulate material in the rumen and was largely excreted in the faeces. Most of the vitamin B12 in whole rumen contents was contained in micro-organisms, but was released on incubation at pH 2. Added cyanocobalamin was partly degraded in the rumen.3. The vitamin B12 to lignin ratio in rumen contents began to decline 1–3 d after cessation of a daily Co drench. Estimated ruminal production of vitamin B12 on full feed was not less than 400–700 μg/d with supplementary Co and 50–110 μg/d from the Co (0.01–0.05 μg/g dry weight) in the basal diet. Production of vitamin B12 appeared to be limited by food intake with or without additional Co.4. At full feed the efficiency of production of vitamin B12 from Co in the basal diet was about 13% while that from added Co was about 3%. Part of the vitamin B12 produced in the rumen was degraded before reaching the faeces and about 5% was absorbed. The minimum total requirements of sheep for vitamin B12 are assessed at about 11 μg/d.5. Injected 5′-deoxyadenosylcobalamin was better retained than injected cyanocobalamin, faecal excretion exceeded urinary excretion with both. Labelled cobalamin was selectively retained by liver (particularly by the mitochondria), kidneys and the walls of parts of the alimentary tract. Vitamin B12 was secreted into the duodenum and reabsorbed in the ileum, but little secretion occurred above the duodenum and little absorption below the small intestine.

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