scholarly journals II. Experimental researches on the strength of pillars of cast iron

1857 ◽  
Vol 8 ◽  
pp. 318-321
Keyword(s):  
Cast Iron ◽  
The Third ◽  
Pass Through ◽  
Experimental Researches

In a previous paper on this subject (Philosophical Transactions, 1840), I had shown,—1st, that a long circular pillar, with its ends flat, was about three times as strong as a pillar of the same length and diameter with its ends rounded in such a manner that the pressure would pass through the axis, the ends being made to turn easily, but not so small as to be crushed by the weight; 2nd, that if a pillar of the same length and diameter as the preceding had one end rounded and one flat, the strength would be twice as great as that of one with both ends rounded; 3rd, if, therefore, three pillars be taken, differing only in the form of their ends, the first having both ends rounded, the second one end rounded and one flat, and the third both ends flat, the strength of these pillars will be as 1—2—3 nearly. The preceding properties having been arrived at experimentally, are here attempted to be demonstrated, at least approximately.

scholarly journals XXXVIII. Experimental researches on the strength of pillars of cast iron from various parts of the Kingdom

1857 ◽  
Vol 147 ◽  
pp. 851-899
Keyword(s):  
Cast Iron ◽  
Royal Society ◽  
Leisure Time ◽  
Point Of View ◽  
Practical Point ◽  
Large Size ◽  
The Subject ◽  
Pass Through ◽  
Experimental Researches

Having in the year 1840 offered to the Royal Society an extensive research upon this subject, which was honoured with the kindest notice of the Society, I felt grateful for the reception it had met with; and though in its preparation it had occupied my leisure time for some years, and contained the results of as many as 277 experiments, which I had made to prove the conclusions arrived at in it, I was still very anxious to improve and extend it. Indeed the importance of the subject would seem to justify every effort I could make for the purpose, when it is considered that a large portion of the houses, warehouses and shops in London, Manchester, Liverpool and throughout the country, depend for their principal supports upon iron pillars, which frequently appear very thin for the weight they have to bear, and being hollow do not allow us to judge from their appearance how small a quantity of metal they have in them, or in other words, whether the building is abundantly strong, or is ready to fall down and crush the persons within it, as has frequently happened to warehouses and other buildings dependent on iron supports. Some of the pillars are made to pass through more than one story, or even are based on the foundation, and support an intermediate floor and the roof. The importance of the subject, in a practical point of view at least, rendered it desirable that a number of pillars of large size should be broken, to obtain data for the application of the principles established in the preceding research; but this was impracticable at that time, notwithstanding the liberality of Mr. Fairbairn, who bore the expense of that inquiry. For by Mr. Fairbairn’s lever then used, more than 18 tons could not be safely applied, and the iron box or frame in which the pillars were broken did not admit pillars of greater length than 7½ feet; but the laborious inquiry in which I was afterwards engaged by Mr. Stephenson, for investigating the properties of the Menai and Conway tubular bridges (that over the Conway in particular), required larger and more powerful apparatus than the preceding, and I can now apply more than three times the pressure formerly used, and break pillars of 10 feet long, and any shorter lengths, with even more accuracy than before.

XX. Experimental researches on the strength of pillars of cast iron, and other materials

1840 ◽  
Vol 130 ◽  
pp. 385-456 ◽  
Keyword(s):  
Cast Iron ◽  
Iron And Steel ◽  
Wrought Iron ◽  
Mechanical Philosophy ◽  
Crushing Force ◽  
The Subject ◽  
Pass Through ◽  
Experimental Researches ◽  
Full Investigation

When we consider to what extent pillars of iron and of timber are used for the support of building's, and reflect that there are no satisfactory rules by which to measure the strength of pillars, it becomes a matter of great importance to obtain such rules by means of experiment, and, if possible, to discover the laws on which they are founded. A feeling of this kind, heightened by the remarks of Dr. Robison, in his Mechanical Philosophy, and by the strongly-expressed opinion as to our want of such knowledge by Mr. Barlow, led me to wish to undertake the inquiry. I mentioned the matter, therefore, to my friend Mr. Fairrairn, who, with that liberality which I have experienced from him on former occasions, at once put every means of a full investigation into my hands. He expressed a wish that I should extend the inquiry to pillars of various kinds, ancient as well as modern; and leave no part of the subject in uncertainty for want of experiments sufficiently varied and extensive. Thus freed from restraint, I endeavoured, in my wish to acquire the requisite information, to forget the expense to which I put my friend, and have made every effort to render the experiments at least ample, correct, and useful. The pillars on which the experiments were made, were mostly of cast iron, as being the material in most general use; but some were of wrought iron and steel, and others of wood. In the earlier experiments, the pillars used were uniform cylinders, either with their ends rounded, so that the crushing force might pass through the axis, or with flat and parallel ends, so that the pillar, when placed between two perfectly parallel crushing surfaces, might have its ends completely bedded against them.

Experimental researches into the strength of pillars of cast iron, and other materials

1843 ◽  
Vol 4 ◽  
pp. 227-228
Keyword(s):  
Cast Iron ◽  
Middle Part ◽  
Experimental Results ◽  
The Other ◽  
Inverse Power ◽  
The Mean ◽  
Pass Through ◽  
Iron Pillar ◽  
Experimental Researches

The author finds that in all long pillars of the same dimensions, the resistance to crushing by flexure is about three times greater when the ends of the pillars are flat, than when they are rounded. A long uniform cast-iron pillar, with its ends firmly fixed, whether by means of disks or otherwise, has the same power to resist breaking as a pillar of the same diameter, and half the length, with the ends rounded, or turned so that the force would pass through the axis. The strength of a pillar with one end round and the other flat, is the arithmetical mean between that of a pillar of the same dimensions with both ends round, and one with both ends flat. Some additional strength is given to a pillar by enlarging its diameter in the middle part. The author next investigated the strength of long cast-iron pillars with relation to their diameter and length. He concludes that the index of the power of the diameter, to which the strength is proportional, is 3·736. He then proceeds to determine, by a comparison of experimental results, the inverse power of the length to which the strength of the pillar is proportional. The highest value of this power is 1·914, the lowest, 1·537, the mean of all the comparisons, 1·7117. He thus deduces, first, approximate empirical formulae for the breaking weight of solid pillars, and then proceeds to deduce more correct methods of determining their strength.

Experimental Third Ventriculostomy Performed Using Endovascular Surgical Techniques and Their Adaptation to Percutaneous Intradural Neuronavigation: Proof of Concept Cadaver Study

Neurosurgery ◽  
2003 ◽  
Vol 53 (2) ◽  
pp. 387-392 ◽  
Author(s):  
Michael B. Horowitz ◽  
Kamal Ramzipoor ◽  
Ajit Nair ◽  
Susan Miller ◽  
George Rappard ◽  
...  
Keyword(s):  
Third Ventricle ◽  
Surgical Techniques ◽  
Cadaver Study ◽  
Brain Parenchyma ◽  
Third Ventriculostomy ◽  
General Anesthetic ◽  
The Third ◽  
Noncommunicating Hydrocephalus ◽  
Pass Through ◽  
The Brain

Abstract OBJECTIVE Endoscopic third ventriculostomy has developed into a therapeutic alternative to shunting for the management of carefully selected patients with primarily noncommunicating hydrocephalus. This procedure, however, requires a general anesthetic and necessitates violation of the brain parenchyma and manipulation near vital neural structures to access the floor of the third ventricle. Using two cadavers and off-the-shelf angiographic catheters, we sought to determine whether it was possible to navigate a catheter, angioplasty balloon, and stent percutaneously through the subarachnoid space from the thecal sac into the third ventricle so as to perform a third ventriculostomy from below. METHODS Using biplane angiography and off-the-shelf angiographic catheters along with angioplasty balloons and stents, we were able to pass a stent coaxially from the thecal sac to and across the floor of the third ventricle so as to achieve a third ventriculostomy from below. RESULTS Coaxial catheter techniques allowed for the percutaneous insertion of a stent across the floor of the third ventricle. Ventriculostomy was confirmed by injecting contrast medium into the lateral ventricle and seeing it pass through the stent and into the chiasmatic cistern. CONCLUSION We describe the performance of third ventriculostomies in two cadavers by use of the new concept of percutaneous intradural neuronavigation. This procedure may obviate the need for general anesthetic and minimize the potential for brain and vascular injury, especially if ultimately combined with magnetic resonance fluoroscopy.

Winter Navigation through the Strait of Belle Isle

1964 ◽  
Vol 17 (4) ◽  
pp. 364-375
Author(s):  
R. E. G. Simmons
Keyword(s):  
The Third ◽  
The Past ◽  
Shortest Route ◽  
Pack Ice ◽  
Normal Period ◽  
Ice Conditions ◽  
Short Season ◽  
Pass Through ◽  
Alternative Routes ◽  
St Lawrence River

The shortest route from the Great Lakes and St. Lawrence River to Europe passes through the Strait of Belle Isle. The alternative routes pass through the Cabot Strait and are between 100 and 400 miles longer according to the European port of destination. The Strait of Belle Isle is, however, normally closed to navigation from the end of December until the middle of July due to the presence of pack ice and icebergs.Air reconnaissance patrols flown over the Labrador, Belle Isle and East Newfoundland areas seem to indicate that, for the past few years at least, ice conditions have not been so severe as to hamper navigation throughout the normal period of closure. Consolidated ice is only present from the third week of January to mid-February and clears in mid-April to mid-May; only icebergs present a problem in May and June. It is hoped t o show that with proper air reconnaisance at the beginning and end of the ice season, navigation through the Strait could be extended to eight or nine months of the year, or even longer, instead of the present short season of only 5½ months.

scholarly journals Health care logistics: mapping and optimization of patients logistics

2021 ◽  
Vol 12 (8) ◽  
pp. 2161-2179
Author(s):  
Daiane Maria de Genaro Chiroli ◽  
Raíza Conde Coradazi ◽  
Fabio Jose Ceron Branco ◽  
Yslene Rocha Kachba ◽  
Franciely Velozo Aragão ◽  
...  
Keyword(s):  
Linear Programming ◽  
Computational Simulation ◽  
Transportation Of Patients ◽  
Patient Transport ◽  
Specific Approach ◽  
Health Region ◽  
The Third ◽  
City Hall ◽  
Pass Through ◽  
The One

Healthcare logistics play an important role in management, being attributed the activities of acquisition, distribution and movement of materials, professionals and patients. This work aims to develop a study, using the healthcare logistics in the movement of patients in the third health region of Paraná, proposing a linear programming problem that will pass through a computational simulation, considering the existing demands and constraints in the system, aiming to optimize the flow of patients from this region. The present study developed four mathematical models, based on demands and constraints followed by linear programming in order to find the best possible solution for the flow of patients from the third health region of the state of Paraná. The study developed reached its goal of optimization, generating an economy in the transportation of patients. Through the analysis of the results, it is concluded that the model that best suits the presented problem is the one of costs minimization, since the one of vehicles presented higher costs. Possibly the model that minimizes the vehicles would bring better results if the vehicles were not outsourced, but of the Ponta Grossa City Hall (PMPG). Was possible to verify the importance of the theme, especially when referring to the flow of patients in the health services due to the lack of studies with this specific approach. Even with the scarcity of data, it is possible to notice the potential for improvements on this patient transport system.

scholarly journals New experimental researches on some of the leading doctrines of Ca­loric ; particularly on the relation between the elasticity, tempera­ture, and latent heat of different vapours; and thermometric admeasurement and capacity

1833 ◽  
Vol 2 ◽  
pp. 97-98
Keyword(s):  
Latent Heat ◽  
Boiling Point ◽  
Elastic Force ◽  
The Third ◽  
Sources Of Error ◽  
Historical View ◽  
Experimental Researches

This paper is divided into three sections. In the first the author, after taking an historical view' of the different experiments under­ taken by Robinson, Watt, Dalton, Biot, and some others, relating to the elastic force of vapours arising from different bodies at dif­ferent temperatures, and after pointing out the sources of error and imperfection to which they are liable, proceeds to describe the ap­paratus which he employed, wdiieh is further illustrated by an an­nexed drawing. The space which contains the vapour for experiment is about half an inch of a barometer tube, against which the oblong bulb of a delicate thermometer rests so as to indicate the true tem­perature. The contrivance is such, that though the liquid and in­ cumbent vapour are restricted to the summit of the tube, its pro­gressive range of elasticity may be measured from 0° to 200° above the boiling point of wrater, or from an elasticity of 0'07 inch to that capable of sustaining 36 feet of mercury, without heating the mer­curial column itself. In this section of the paper are several tables of results, showing the elastic force of the vapour of water in inches of mercury, at temperatures between 24° and 312° ; and also that of alcohol, ether, oil of turpentine, and naphtha. The second section of Dr. Ure’s paper relates to thermometric admeasurement, and to the doctrine of capacity. He does not consider the thermometer liable to the uncertainties which are supposed to belong to it by Mr. Dal­ton, but that it is an equable measure of heat, in consequence of its possessing an increasing rate of expansion, and w'hich is compensated for by a quantity of the quicksilver getting out of the bulb into the tube, and consequently out of the action of the heat, the bulb being the only part heated in all ordinary cases. In the third section, relating to the latent heat of different vapours, Dr. Ure details experiments made to ascertain the caloric existing in different vapours, and the temperatures at which they respectively acquire the same elastic force.

The passage of staphylococci through the bovine teat canal

1968 ◽  
Vol 35 (3) ◽  
pp. 399-406 ◽  
Author(s):  
D. Forbes
Keyword(s):  
Staphylococcus Aureus ◽  
The Other ◽  
Intramammary Infection ◽  
Milk Samples ◽  
The Third ◽  
Colony Forming Unit ◽  
Before And After ◽  
Efficient Machine ◽  
Pass Through ◽  
Teat Canal

SummaryIn order to determine how bacteria pass through the teat canal into the teat sinus, milk samples were taken by syringe, through the teat wall, from 12 quarters of 7 cows, before and after each milking for up to 16 days. Three of the teat canals were naturally infected before the start of the experiment and the remainder were artificially infected with Staphylococcus aureus by the Hadley–Wisconsin swab technique. In 3 of the quarters the inoculum was introduced into the teat sinus through the teat canal by the inoculation technique although the swabs were inserted only 3–5 mm into the canal. The other 9 of the 12 quarters were milked a total of 149 times during the experiment but only once was a colony-forming unit of the bacterium present in a teat canal infection isolated from the milk taken from the teat sinus after milking. One quarter developed an intramammary infection, the bacterium first being detected in the teat sinus prior to the third milking after inoculation of the teat canal. The invasion of the bacteria into the teat sinus therefore occurred between milkings. Staph. aureus persisted in teat canals between 5 and 32 or more milkings after inoculation. The experiment showed that bacteria in the teat canal are seldom refluxed into the residual milk in the teat sinus during correctly conducted milking with an efficient machine.

scholarly journals Taming, Domestication and Exaptation: Trajectories of Transposable Elements in Genomes

Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3590
Author(s):  
Pierre Capy
Keyword(s):  
Genetic Variability ◽  
Transposable Elements ◽  
Environmental Constraints ◽  
The Third ◽  
Evolutionary Trajectories ◽  
Pass Through ◽  
Horizontal Transfers ◽  
Population Fitness

During evolution, several types of sequences pass through genomes. Along with mutations and internal genetic tinkering, they are a useful source of genetic variability for adaptation and evolution. Most of these sequences are acquired by horizontal transfers (HT), but some of them may come from the genomes themselves. If they are not lost or eliminated quickly, they can be tamed, domesticated, or even exapted. Each of these processes results from a series of events, depending on the interactions between these sequences and the host genomes, but also on environmental constraints, through their impact on individuals or population fitness. After a brief reminder of the characteristics of each of these states (taming, domestication, exaptation), the evolutionary trajectories of these new or acquired sequences will be presented and discussed, emphasizing that they are not totally independent insofar as the first can constitute a step towards the second, and the second is another step towards the third.

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