bluuebunny/crossref_metadata_2025 huggingface dataset:
A Feasibility Study of a Culturally Tailored Diabetes Intervention for Mexican Americans
Authors: Vincent Deborah , Pasvogel Alice , Barrera Lourdes
Published: October 2007

Latinos, the fastest growing minority group in the United States, are among the hardest hit by diabetes. Among Latinos, Mexican Americans have the highest rate (23.9%) of diabetes. Good self-management can improve glycemic control and decrease diabetes complications but can be challenging to achieve. The purpose of this study was to test the feasibility and examine the effects of a culturally tailored intervention for Mexican Americans with type 2 diabetes on outcomes of self-management. The study used a pretest/posttest control group design with 10 participants in each group ( N = 17). Feasibility and acceptability of the tailored diabetes self-management program was assessed by examining ease of recruitment and retention rates. The behavioral outcomes of self-efficacy, diabetes knowledge and self-care measures, and the biologic outcomes of weight, body mass index, HbA1C, and blood glucose were used to examine intervention effectiveness. Successful recruitment of participants came from personal referrals from providers or the promotora. Retention rates were 100% for the intervention group and 80% for the control group. Findings suggest that the intervention had a positive clinical and statistical effect on diabetes knowledge, weight, and body mass index. Improvements were also noted in self-efficacy scores, blood glucose, and HbA1C, but these changes did not reach statistical significance. A culturally tailored diabetes self-management program may result in improved outcomes for Mexican Americans with type 2 diabetes.
Use of General Clinical Research Centers for Nursing Research
Authors: Payne Judith K. , Yenser Sarah E.
Published: October 2007

This study examines to what extent academic nursing faculty members understand the purpose of general clinic research centers (GCRCs) and use this resource in their programs of research. GCRCs provide a controlled research-oriented infrastructure to conduct safe, innovative, and multidisciplinary studies. Survey questionnaires were sent to associate deans of research at schools of nursing accredited by the Commission on Collegiate Nursing Education or the National League for Nursing Accrediting Commission within 60 miles of a GCRC. They were asked to distribute questionnaires to 20% of faculty members. Of the 186 nurse faculty members responding, 85% had not conducted research at a GCRC as a principal investigator and 69% of the sample reported that their colleges or universities do not make information about GCRCs available to new faculty. Making greater use of this valuable resource allows nurse researchers to become more involved in developing new knowledge and testing interventions and in psychological and physiologic measurements, thus doing more to fulfill the mission of nursing research and increasing the involvement of nurses in the broader community of health science research.
The Effects of Vitamin D Deficiency and Insufficiency on the Endocrine and Paracrine Systems
Authors: Alpert Patricia T. , Shaikh Ulfat
Published: October 2007

Individuals are capable of producing vitamin D with proper exposure to sunlight. However, several factors can interfere with the effectiveness of this process. Most sunscreens filter out UVB light, thus inhibiting vitamin D production. Individuals with more darkly pigmented skin have greater difficulty producing vitamin D because melanin acts as an effective natural sunscreen, requiring longer sun exposure to produce an adequate daily allotment of vitamin D. Additionally, solely breastfed infants whose mothers suffered from vitamin D deficiency or insufficiency when pregnant have smaller reserves of the nutrient and are at greater risk of developing nutritional rickets. Vitamin D deficiency leads to rickets, osteomalacia, and osteoporosis. Long-term vitamin D insufficiency can lead to paracrine effects such as type 1 diabetes, cancer, and multiple sclerosis. This article reviews the current literature on vitamin D deficiency and insufficiency and their relation to different disease states. Potential areas for research are discussed.
Perspectives of Family Medicine Physicians and Licensed Acupuncture Clinicians on Caring for Persons With Unexplained Chronic Fatigue
Authors: Daly Jeanette M. , Hartz Arthur J.
Published: October 2007

Unexplained chronic fatigue (UCF) is a poorly understood condition with little known about its etiology and treatment. A wide range of health care providers, including physicians, nurse practitioners, and complementary and alternative medical practitioners, offer services for persons with UCF. This study explored perspectives of family medicine physicians and licensed acupuncture clinicians with experience in treating patients with UCF, regarding their treatment regimens and perceived success at improving their patients' energy and coping with symptoms. A sample of 141 family medicine physicians and licensed acupuncturists was surveyed via a questionnaire; 48 returned the completed questionnaire. Clinicians reported treating from 3 to 375 patients with UCF. Family physicians provided more conventional methods, and licensed acupuncturists provided alternative treatments. The reported success of the licensed acupuncturists at improving energy and stamina and helping patients cope with fatigue was significantly higher than that of the family physicians. Implications for future research are discussed.
A Case Report of the Treatment of Diabetic Foot Ulcers Using a Sodium Hyaluronate and Iodine Complex
Authors: Sobotka Lubos , Smahelova Alena , Pastorova Jana , Kusalova Marie
Published: October 2007

Diabetic foot ulcers are difficult to heal due to defects in local microvasculature and persistent, concomitant infection. Despite the best medical care, amputation is often a management option for this problem. The authors have developed a new and unique system for wound treatment, which is based on a combination of high molecular weight sodium hyaluronate with an iodine complex—Hyiodine® (Contipro C, Dolní Dobrouc, Czech Republic). In this case report, the authors present an observational study on a series of patients with diabetic foot disease with nonhealing wounds treated with Hyiodine. The effect of the HA-iodine complex was studied on 18 patients suffering from complicated foot diabetic wounds. The HA-iodine complex was either spread directly over the wound, or more frequently, gauze was immersed in the HA-iodine complex and then put on/into the wound. Then several layers of dry gauze covered the wound. This dressing was changed every 24 hours. Wound healing was monitored daily, and wound pictures were taken each second week. Clinical improvement was observed in the majority. This suggests that the HA-iodine complex dressing has potential that needs to be developed from controlled studies.
A Retained Sponge Is a Complication of Vacuum-Assisted Closure Therapy™
Authors: Saeed Musab U. , Kennedy Donald J.
Published: October 2007

Vacuum-assisted closure (VAC) system has become a widely used, efficacious, and overall safe method for managing many types of open wounds. The authors present a case of a rare but avoidable complication caused by a retained piece of sponge after VAC therapy™ (KCI Inc, San Antonio, TX). They emphasize the need for awareness and careful evaluation of the patient who receives VAC therapy to avoid diagnostic confusion and morbidity to the patient.
Extracting spurious messages from noise and risk of schizophrenia-spectrum disorders in a prodromal population
Authors: Hoffman Ralph E. , Woods Scott W. , Hawkins Keith A. , Pittman Brian , Tohen Mauricio , Preda Adrian , Breier Alan , Glist Jill , Addington Jean , Perkins Diana O. , McGlashan Thomas H.
Published: October 2007

A tendency to extract spurious, message-like meaning from meaningless noise was assessed as a risk factor leading to shizophrenia-spectrum disorders by assessing word length of speech illusions elicited by multispeaker babble in 43 people with prodromal symptoms. These individuals were randomised to olanzapinev.placebo groups during year 1 followed by no pharmacological treatment for those with no disorder conversion during year 2. A time-dependent Cox regression analysis of conversion to schizophrenia-spectrum disorder revealed a significant interaction between condition (olanzapinev.no drug) and length of speech illusion, with the latter strongly predicting subsequent conversion during medication-free intervals but not during olanzapine treatment.
Social and cognitive functioning, urbanicity and risk for schizophrenia
Authors: Weiser Mark , van Os Jim , Reichenberg Abraham , Rabinowitz Jonathan , Nahon Daniella , Kravitz Efrat , Lubin Gad , Shmushkevitz Moti , Knobler Haim Y. , Noy Shlomo , Davidson Michael
Published: October 2007

Background

Previous work suggests that the association between urbanicity and schizophrenia may be greatest in those with pre-existing vulnerability.

Aims

To test for synergism in risk of schizophrenia between population density and a combined exposure of poor premorbid social and cognitive functioning.

Method

For 371 603 adolescent males examined by the Israeli Draft Board on social and cognitive functioning, data on population density of place of residence and later hospitalisation for schizophrenia were obtained from population-based registries.

Results

There was an interaction between population density (five levels) and poor premorbid social and cognitive functioning (interaction χ2=4.6,P=0.032). The adjusted increase in cumulative incidence associated with one unit change in population density was 0.10% in the vulnerable group (95% CI 0.019–0.18,P=0.015), nine times larger than that in the non-vulnerable group (0.011%, 95% CI 0.0017–0.020,P=0.021).

Conclusions

Risk of schizophrenia may increase when people with a genetic liability to the disorder, expressed as poor social and cognitive functioning, need to cope with city life.
Screening young people for obsessive-compulsive disorder
Authors: Uher Rudolf , Heyman Isobel , Mortimore Catherine , Frampton Ian , Goodman Robert
Published: October 2007

Obsessive-compulsive disorder (OCD) in young people is underrecognised and undertreated. Simple screening tools suitable for general practice and community services are needed. We created a seven-item self-report Short OCD Screener (SOCS) and administered it to young people aged 11–15 years, including 116 patients with OCD, 181 healthy community controls and 33 young people with other psychiatric diagnoses. The SOCS has excellent sensitivity of 0.97 (95% CI 0.91–0.98) to detect OCD cases. Its specificity is good in children without psychiatric diagnoses, but low in a psychiatric sample. The SOCS is a screening tool suitable for community but not specialist settings.
Mental capacity in psychiatric patients
Authors: Okai David , Owen Gareth , McGuire Hugh , Singh Swaran , Churchill Rachel , Hotopf Matthew
Published: October 2007

Background

Mental capacity is central to legal and ethical debates on the use of compulsion in psychiatry.

Aims

To describe the clinical epidemiology of mental incapacity in patients with psychiatric disorders, including interrater reliability of assessments, frequency in the psychiatric population and associations of mental incapacity.

Method

Cross-sectional studies of capacity to consent to treatment for psychiatric patients were systematically reviewed from Medline, EMBASE and PsycInfo databases. Information on the reliability of assessments, frequency and associations of mental incapacity was extracted.

Results

Out of 37 papers reviewed, 29 different capacity assessment tools were identified. Studies were highly heterogeneous in their measurement and definitions of capacity. Interrater reliabilities between tools were high. Studies indicate incapacity is common (median 29%) but the majority of psychiatric in-patients are capable of making treatment decisions. Psychosis, severity of symptoms, involuntary admission and treatment refusal were the strongest risk factors for incapacity.

Conclusions

Mental capacity can be reliably assessed. The majority of psychiatric in-patients have capacity, and socio-demographic variables do not have a major impact but clinical ones do.
Aggressive behaviour, victimisation and crime among severely mentally ill patients requiring hospitalisation
Authors: Hodgins Sheilagh , Alderton Jane , Cree Adrian , Aboud Andrew , Mak Timothy
Published: October 2007

Background

Severe mental illness is associated with increased risk of aggressive behaviour, crime and victimisation. Mental health policy does not acknowledge this evidence. The number of forensic beds has risen dramatically.

Aims

To examine the prevalence of aggressive behaviour, victimisation and criminality among people receiving in-patient treatment for severe mental illness in an inner-city area.

Method

Self-reports of aggressive behaviour and victimisation and criminal records were collected for 205 in-patients with severe mental illness.

Results

In the preceding 6 months 49% of the men and 39% of the women had engaged in aggressive behaviour and 57% of the men and 48% of the women had been victims of assault; 47% of the men and 17% of the women had been convicted of at least one violent crime.

Conclusions

Aggressive behaviour and victimisation are common among severely mentally ill people requiring hospitalisation in the inner city. Rates of violent crime are higher than in the general population.
“A Home Made Sacred by Protecting Laws”: Black Activist Homemaking and Geographies of Citizenship inIncidents in the Life of a Slave Girl
Authors: Rifkin Mark
Published: October 2007

mark rifkin is Assistant Professor in the English Department at Skidmore College. His essays have appeared or are forthcoming in boundary 2, glq, and American Literature. He recently completed his first book manuscript, “Manifesting America: The Imperial Construction of National Space, 1776-1861,” and is at work on his second, “When Did Indians Become Straight?: Kinship, Compulsory Heterosexuality, and the Representation of Native Peoples.”
First Report of the Welding Research Committee. A Preliminary Research into the Effect of Heat Treatment of Welds
Authors: Schuster L. W.
Published: October 2007

With such considerations as the releasing of internal stress, the effect on corrodibility, and the practicability of carrying out high-temperature treatments, the present research does not deal. The experiments concern solely the changes in toughness brought about by heat treatment, and they represent a trial set of tests in which a particular high-class electrode was used, the results being intended as a guide for future research.

In the past there has been considerable variability in the results obtained from a normalizing treatment by different experimenters, and as this was considered to be partly due to a difference in manner of cutting out the samples and a difference in the method of carrying out the treatment, the present treatments were all kept under careful control. The upper and lower “runs” were tested separately so that the effect of heat treatment on the coarse metal of the upper run and the fine metal of the lower runs might be subdivided.

Throughout, microscopic examinations were made so that the change in structure might be correlated as far as possible with the change in the shock value. The particular weld metal tested gave very consistent results and the change in Izod value was found largely to follow the change in grain size.
Oil Storage and Transport Equipment, with Special Reference to the Application of Welding
Authors: Adlington R. E.
Published: October 2007

Primarily owing to the special nature of the fluids handled in the oil industry, welding has thoroughly established itself, and is being increasingly employed in all phases of oil refining and handling. Various types of tanks, treatment vessels, and pipe lines of all-welded construction are now being used for the most searching fluids, with complete absence of the joint leakage which occurred with the older methods of construction. Welding methods also show substantial reductions in material and site costs.

In order to indicate the very large number of examples of welded construction as applied to the storage and transport of oil, the subject is dealt with on the basis of a flow sheet which shows generally how an oil, found abroad and conveyed to this country for refining, is handled from the time it leaves the well until it is ready for the consumer. Reference is mostly made to commonly used liquid petroleum products such as motor spirit, lubricating oil, furnace, and Diesel oil. The handling of these products is described with reference to the methods employed by one or two well known concerns, but such methods are typical of those employed in other parts of the world.
The Development of Automatic Combustion Control Systems for Industrial and Power Station Boilers
Authors: Hodgson J. L. , Robinson L. L.
Published: October 2007

The paper shows that automatic control systems have been developed mainly in order to prevent smoke, to maintain load against demand, to carry out routine adjustments, to facilitate the group control of boilers, to increase boiler house efficiencies, and to provide interlocking safeguards and self-acting cut-out devices.

Dealing with principles and methods rather than with mechanical details, the paper describes with reference to fundamental diagrams and special drawings the main features and capabilities of thirteen of the more important control systems. The paper deals also with the factors upon which speed of response and accurate combustion control depend, questions of boiler feed, the elimination of “hunting” of the controls, and the considerations which affect the choice of mechanisms for operating the controls.

Test results are given, and the desirability of using automatic combustion control, even in the case of base-load stations, is urged.
Some Factors in the Design of Surface Condensing Plant
Authors: Guy H. L. , Winstanley E. V.
Published: October 2007

It is suggested that the poor performance of certain large surface condensers is due to pressure drop on the steam side. Tests are given showing the pressure drop for various patterns of tube plates and illustrating the steps taken to reduce it. The effect of pressure drop upon the mean temperature difference is discussed. The limitations of accepted formulae are criticized and the results of more accurate analysis are presented.

The results of Eagle and Ferguson's tests on heat transmission from tube to water are presented in terms of the external surface for the range of normal condensing plant. Utilizing these results, the overall rates of heat transmission from a large number of tests on commercial condensers are analysed in order to obtain the rate of heat transmission from steam to tube, and after a discussion of the results a mean value is suggested. A set of curves of overall rates of heat transmission on this basis is presented as applicable to brushed tubes. A method of obtaining the net heat rejected to the circulating water in power plant is developed and the departure from the conventional figure of 1,000 B.Th.U. per lb. is brought out. The results obtained on a series of tests on individual tubes in a complete condenser are analysed and commented upon.

The paper also deals with the effect of tube fouling upon the overall rate of heat transmission, and methods of obtaining a margin in surface to allow for this are discussed. The effect of pressure drop upon the duty of an air extraction plant and certain problems arising therewith are discussed. Some actual air leakage tests are given and compared with recognized standard allowances. The authors deal with the friction on the water side of condensers and give test figures of the friction in the tube with various methods of tube plate fastenings. Recommended standard values of the various factors for assessing condenser water friction are given, together with tests from commercial installations.

The paper concludes with a treatment of the problem of syphonic return in condenser circulating water systems and gives a method of calculating the syphonic efficiency.
The Stresses in Thick-Walled Cylinders of Mild Steel Overstrained by Internal Pressure
Authors: Cook Gilbert
Published: October 2007

The paper describes a theoretical and experimental investigation of the stress distribution across the walls of thick cylinders of mild steel when the internal pressure is such that the elastic limit of the material is exceeded and a certain amount of overstrain occurs. The main conclusions are:—

(1) That in the cylinders in which it was possible to produce overstrain over the whole wall thickness the observed pressure is in close agreement with that calculated on the assumption of constant shear stress equal to the shear stress observed during plastic yield in tension. (2) That in partially overstrained cylinders the maximum shear stress in the elastic region varies as overstrain proceeds. (3) That at the internal surface the effect of overstrain is to reduce the circumferential tensile stress, and to set up an axial compressive stress. With sufficient wall thickness all three principal stresses at the internal surface become compressive for pressures which still permit of the external portions remaining elastic.
Design of Crane Hooks and Other Components of Lifting Gear
Authors: Gough H. J. , Cox H. L. , Sopwith D. G.
Published: October 2007

Most lifting gear components consist essentially of curved beams of very ductile material, the radius of curvature often being small in comparison with the dimensions of the beam. In addition, in rings, chain links, etc., the distribution of bending moment is not directly calculable from the values of the applied loads, but is influenced also by the condition that the centre line of the section of the component must remain continuous when under load.

The design of lifting gear components requires, therefore, the determination of the bending moments, etc., set up, the calculation of the stresses due to these bending moments, etc., and the consideration of the modification to the stress system consequent upon yielding in parts of the components. The effect of the curvature of the centre line of the component on the distribution of stress is first discussed, the method of calculation for different forms of beam section being indicated, and the best form of section investigated. The effect of yielding is next considered. It is shown that, if any portion of the component yields under load, the removal of the load will leave this portion in a state of stress of opposite sign to that under which it yielded, and it is concluded that calculated stresses even as high as the sum of the yield stresses in tension and compression may be actually set up in the material as ranges of stress without causing continuous plastic deformation. The general method of calculating the bending moments in rings and links, etc., is demonstrated and comparison is made between exact and approximate methods. General formulæ for egg links (including rings and chain links), studded links, and eyebolts are obtained and typical examples, drawn from recent British Standard Specifications, are worked out.

The results of tests on components designed according to the general principles of the paper are described and the use of fatigue testing both in determining the true factor of safety and as an experimental check on the calculations is demonstrated.
Hydrodynamic Principles of Journal Bearing Design
Authors: Swift H. W.
Published: October 2007

A survey of existing theories of the journal bearing without side leakage suggests that optimum conditions as regards friction and film thickness are obtained when the bearing is designed with such a clearance that the operating eccentricity, in the case of the half-bearing, is about 0·4. Reasons are given for assuming that a similar optimum eccentricity exists in bearings of ordinary width.

In order to take rational account of side leakage, use is made of Kingsbury's experimental results obtained by electrical analogy. Coefficients are deduced embodying the effect of bearing width on friction and film thickness, and for a given total load it is found that the film thickness increases continuously with the width of bearing, but the frictional coefficient has a minimum value when a certain ratio exists between the width of a bearing and its diameter; in the case of the half-bearing, the ratio is about 3/2.

For a specified minimum film thickness the necessary width Bo of the bearing can be found, and the rational procedure in design differs according as the journal diameter D is greater or less than . The critical diameter is jointly dependent on the least permissible clearance and the hydrodynamic data. A discussion of practicable clearances leads to a working expression for this critical diameter, which is conveniently written in the form , where W is the bearing load in pounds, and D1 the critical diameter in inches. The symbol Ds, defined as the specific diameter, is plotted in Fig. 9, p. 424.

The following procedure is suggested in design. For the given speed, N r.p.m., the specific diameter D s is read from Fig. 9 and the critical diameter for a bearing load of W lb. is then for oil of normal viscosity. If the actual journal diameter D < D1 the bearing width should be and the diametral clearance

This gives the lowest friction consistent with safe film thickness. If D > D1 the bearing width B should be and the diametral clearance

This gives optimum frictional conditions and a margin of safety in film thickness. Comparative data for bearing arcs of 120 deg. and non-central loads are shown in Table 2, p. 412.
Textile Machinery for the Production of Worsted Yarn
Authors: Waterhouse David
Published: October 2007

The paper reviews the following operations in worsted yarn production: wool combing and its evolution, with descriptions of the Lister, Noble, and Heilmann machines; worsted drawing on the Bradford, Continental, and Anglo-Continental systems; gilling, with an account of the various types of machine in use; spinning and its evolution, with descriptions of worsted, flyer cap, and ring frames, and of the mule; and the evolution of automatic doffers.
The Organization and Mechanical Appliances of the London Fire Brigade
Authors: Morris C. C. B.
Published: October 2007

To produce a sufficient pressure for fire-fighting purposes in water from low-pressure mains, turbine pumps are driven from the gearbox of the road engine, auxiliary pumps being fitted for priming the main pumps. The normal pump pressure employed demands a special quality of hose to ensure that all service requirements are met. The round-thread screw coupling for hose is compared with the instantaneous coupling.

When water supply is inadequate at fires, pumps are inserted “in series” at suitable points in long lines of hose, to bring water over considerable distances. “Collector” working enables water supplies from various sources to be combined, the various lines of hose being joined by “collector boxes” with non-return valves.

Dual-purpose appliances, incorporating a standard chassis with an escape and a small “first-aid” pump and tank, are extremely useful; the pump is sufficient to deal with about 25 per cent of the fires occurring in London. An all-steel turntable ladder, incorporating a number of special features, is also described.

“Special service” calls, to accidents not involving fire, are continually increasing in numbers. Emergency vans, fitted with dynamos and floodlighting equipment, oxy-acetylene cutting plant, etc., have been designed for such accidents. Portable breathing apparatus is also provided, and is often used at actual fires as well as at special service calls.

The leading dimensions of the fire float Massey Shaw are given. The author describes the organization required for mobilizing appliances for attendance at fires; the division of the London area into special districts for fire calls, and the provision of “key” stations; and finally the procedure adopted at fires.
Present Tendencies in Water Turbine Machinery
Authors: Fulton A. A.
Published: October 2007

As the high specific-speed water turbine has been fully described elsewhere, the paper concentrates on the present state of knowledge and details of design of the remaining types of water turbines, namely, Francis turbines and Pelton water wheels.

In the absence of any spectacular developments in performance, efficiency, or speed regulation during the last twenty years, notable progress has been made in several other directions, such as the increased size of units, the more advanced state of knowledge regarding the incidence and avoidance of cavitation, and the use of special materials and devices to combat particular problems.

On the subject of cavitation, the paper stresses the importance of the influence which the discharge velocity from the runner has on the allowable static suction head, and so directly on the occurrence of cavitation. The author goes on to describe how the effects of localized cavitation can be eliminated both in Francis and Pelton turbines, and thereafter reviews the settings and arrangements of Francis and Pelton turbines which are mostly favoured to-day, including brief references to arrangements of special interest.

The latter part of the paper discusses the new ideas which are being tried out in the design and manufacture of the various portions of the two types of turbines dealt with in the paper. Among such features are included the use of welding in the repair of runners and in the manufacture of casings, and other portions of water turbines; the use of rubber in runner clearances and water-lubricated bearings; the researches carried out to determine the best form and shape of suction tubes for double-runner turbines; the difficulties encountered in the cracking and fixing of Pelton buckets; and finally, a review of the several types of main inlet valves at the disposal of the turbine designer.
The Conversion of the Stanton 3-Inch High-Speed Wind Tunnel to the Open Jet Type
Authors: Bailey A. , Wood S. A.
Published: October 2007

The 3-inch high-speed wind tunnel developed by Stanton has been converted in the Engineering Department of the National Physical Laboratory to the open jet principle, the working jet now being contained in a square glass-sided chamber. The pressure in the observation chamber can be controlled within certain limits by altering the axial length of the gap between the inlet and outlet, and the presence of standing waves in the jet can be largely eliminated by bringing the chamber pressure to a value equal to that in the jet at the chamber inlet.

In place of the divergent jet used by Stanton, an approximately parallel working jet has been obtained in the modified tunnel by using inlet nozzles with profiles determined by a graphical construction based on the “characteristic curve” method given by Busemann. An optical system has also been fitted enabling Schlieren photographs of the flow pattern to be obtained. Measurements of the wave systems set up round model cones indicate agreement with the theory established by Taylor and Maccoll which they found to accord with the results of larger-scale firing trials on conical-headed shell, thus providing evidence of the close similarity between conditions in the tunnel and on the full scale.
Water Hammer in Pipes, Including Those Supplied by Centrifugal Pumps: Graphical Treatment
Authors: Angus Robert W.
Published: October 2007

The damage done to pipes as a result of water hammer is so serious that no engineer can afford to neglect it in the design of long pipes, particularly those under low heads. Unfortunately the problem has appeared to many to be very intricate, and indeed the mathematical treatment is so involved and so lengthy that few practising engineers would attempt to solve water-hammer problems mathematically. In many cases a purely arbitrary rule has been employed in finding the pressure rise, with little knowledge on the part of the engineer as to whether the formula fits his case or not, and thus much money may be wasted on too heavy a line, or, on the other hand, it may be so light as to be dangerous.

In the following treatment of the subject, the rigid theory has first been explained and some problems have been solved, but most of the paper deals with the elastic (and correct) theory. A problem is first worked out by the arithmetical integration method in order to establish ideas and to make the subsequent argument clear. The fundamental equations giving rise to Allievi's equations must be clearly understood for a grasp of the true relationships that exist, and these have been treated in some detail, but it is safe to say that if the argument has been followed up to the end of the general equations, no difficulty will be experienced with the graphical treatment.

In explaining the diagrams, very simple cases are first dealt with and the elegance of the method will make an appeal at once. The water-hammer pressure can be found for any simple pipe, and at any point on the pipe, and for any chosen gate movement, and results can be obtained with accuracy in less than thirty minutes in simple cases. For compound pipes, the solution is nearly as rapid. The pressures arising in the discharge lines from pumps have been fully discussed in the case of pumps with small inertia, and also in cases in which the inertia is large enough for consideration, when an existing pump has been employed to supply the data used.

The accuracy of the method is beyond question; where intersections are at small angles the exact points are hard to determine, but this trouble may easily be avoided by changing the scales. If a slide rule is used in solving the problem mathematically the corresponding case will be encountered.
The Application of the Locomotive to Traffic Working
Authors: Fairless Thompson
Published: October 2007

The paper describes methods by which the analysis of steam locomotive power can be most advantageously applied to traffic working in the case of railways not having special testing facilities, such as dynamometer cars.

The first section describes the method used for the determination of cylinder and boiler output, the treatment of locomotive and train resistances, and the application of these factors to train loading, speed, and running time. The calculation of fuel and water consumptions on a horse-power-hour basis is given, also the method of application to train working.

The second section describes the procedure for the practical application of locomotive power to traffic working, and the measurement of train capacity in terms of ton-kilometres per train hour.
Modern Rolling Mill Design
Authors: Poole A.
Published: October 2007

After surveying the various types of hot rolling mill units for heavy ingots and their evolution, the author selects for description certain examples of progressive design from his own recent experience. These include an adaptation of modern heavy mill manipulation to an existing blooming mill, incorporating fabricated steel structures in place of steel castings for mill tables, small hand-worked mills for the accurate finish of high-class steels in small bar sizes, a modern high-production four-strand continuous wire rod mill plant, and two examples of development in rolling mill auxiliaries. The question of roll neck bearings is discussed and a special bronze and white-metal combination roll neck bearing is described.
Overhead Electric Travelling Cranes
Authors: Ellis John H.
Published: October 2007

The installation of an overhead electric crane is often left in the hands of specialist manufacturers. Plant engineers, however, need to ascertain service and performance requirements when considering an installation, and they often rebuild or modify existing cranes in order to reduce production and maintenance costs by improving the reliability of the crane service.

The paper considers some of the factors affecting the installation of suitable cranes for particular duties, and deals briefly with some of the important features of design. A few service troubles are dealt with and some instances are quoted from the experience of a steelworks maintenance department with reference to the subject of improvements and maintenance costs.
The Distortion of Metals by Cold Working
Authors: Wainwright H. A.
Published: October 2007

The paper deals with current conceptions of cold working and its varied effects on the metal undergoing deformation. The mechanism and behaviour of single metal crystals and polycrystalline aggregates, whilst undergoing cold working deformation, are outlined. Two aspects are treated, namely, block slip and “twinning”.

The X-ray examination of a polycrystalline metal under deforming stresses is mentioned, together with the formation of flow lines, better known as Lüder's lines. The effect of cold work on the mechanical, physical, electrical, and chemical properties of materials is then considered in some detail, together with the practical aspects of the changes wrought.

The paper concludes with a brief summary of the subject, and the more important theories are reviewed in order to see how far they explain all the phenomena observed.
British Engineering Societies and Their Aims
Authors: Mowat Magnus
Published: October 2007

The medieval guilds were the forerunners of engineering societies and were followed by scientific bodies. The activities and objects of the Institution of Civil Engineers and the Institution of Mechanical Engineers are described, with notes on other national and local associations in Great Britain.
The Pressure Distribution in a Convergent-Divergent Steam Nozzle
Authors: Binnie A. M. , Woods M.W.
Published: October 2007

The paper describes experiments performed to determine the pressure distribution in a convergent-divergent steam nozzle of rectangular cross-section. By means of pressure tappings drilled along the axis, it was found that, in the course of its passage through the nozzle, initially superheated steam expanded continuously until condensation commenced, when a sharp rise of pressure (of the order of 1 lb. per sq. in.) occurred. Up to this point the observations were consistent with the predictions of Callendar's equation for the isentropic expansion of superheated and supersaturated steam: the friction loss was small as far as the throat of the nozzle, but in the divergent portion it was of appreciable magnitude.

The Wilson line was determined after allowances for the effects of friction had been made. The pressure rise was also investigated in detail and was found to be accompanied by a decrease of velocity and an increase of total heat. At the peak of the rise, where continuous expansion recommenced, the steam was probably not in thermal equilibrium.

Additional tappings were placed across the throat, where the pressure observations were in close agreement with the values demanded by Taylor's theory. This theory, which does not assume uniformity of conditions over cross-sections of the nozzle, is more accurate in the neighbourhood of the throat than the classical theory of Reynolds.
The Effect of Circumferential Pitch of Steam Turbine Blades on Torque as Compared with “Biplane Effect” on the “Lift” of Aerofoils
Authors: Dowson Robert
Published: October 2007

It is known that the “lift” of biplanes and triplanes per unit of wing surface is inferior to that of a monoplane, and that the degree of departure depends upon the gap-chord ratio. Published data indicate that the lift increases with increasing gap, apparently towards some limiting value. Regarding steam turbine wheels as rings of multiplanes, it may be asked, Is there any direct evidence that the torque on each blade is influenced by the presence of the other blades?.

Many experiments have been made to determine the optimum circumferential pitch for a given blade shape, but most of these have aimed simply at arriving empirically at the best efficiency, without inquiry into the factors involved. The experiments described in the paper were carried out with low-velocity reaction blading, and were aimed at eliminating as many factors as possible, so as to make a clear issue of the effect of spacing the runner blades closer or wider apart. These experiments indicated that the effect of circumferential spacing on maximum torque was fairly critical, and that from the optimum point the torque declined less rapidly with increasing spacing than with decreasing spacing.

The decline in torque with increasing spacing is due probably to lack of proper guidance of the steam, only a portion of which gives up energy to the runner blades, the remainder doing little useful work. On the other hand, the curve of force per blade is found to be increasing with increased circumferential pitch, towards some optimum value (beyond the range of the experiments). This curve resembles closely that published for the increased “lift” on a biplane as the planes are spaced farther and farther apart.

The experiments are of interest on account of the above analysis and comparison, but no definite conclusion is possible without further investigation.
The Transmission of Superheated Steam over Long Distances
Authors: Genève L. F. C. A.
Published: October 2007

The aim of the paper is to obtain as accurate a solution as possible to problems arising in the transmission of superheated steam over long distances for ( a) industrial heating and ( b) power generation. After a general survey, with a description of two typical installations, the problem is discussed under headings ( a) and ( b), and the usual practice in fixing steam velocities is given. The present state of knowledge of radiation losses is reviewed; first, the standard English practice of using a coefficient based on the pipe surface and varying with the thickness of the insulating material; and second, the method, used mainly in America, which involves conductivity coefficients. The effect of air currents on heat loss is investigated and a new equation is deduced for the equivalent velocity past the pipe, due to natural convection.

Standard formulæ for the coefficient of friction and the viscosity of steam are discussed; for the former a new formula of the rectangular hyperbola type is derived from Carnegie's results and corrected for roughness. Steam viscosity is considered in the light of Speyerer's and Sigwart's investigations; curves of Sigwart's results are plotted on a convenient base of logarithms of pressures.

Conditions during flow in a horizontal straight pipe with perfect insulation are considered and new equations, simplifying the problem, are derived from the fundamental equations.

The author treats from a new viewpoint the problem of power transmission by steam over long distances, based on the loss of available Rankine heat drop. Numerical examples are worked out, as also is the effect of air currents on the coefficient of heat loss. Finally the limiting factors, including the effect of radiation losses, in the long-distance transmission of steam are analysed and their practical importance is discussed.
Practical Problems in Spring Design
Authors: Berry W. R.
Published: October 2007

The author draws attention to the difficulties facing the engineer to whom spring design is merely incidental. These difficulties are mainly due to the complicated formulæ concerned, to lack of information regarding the materials, and to incorrect appreciation of the real functions of the spring. Standard formulæ require corrections for the effect of curvature; without these adjustments very dangerous results can be obtained. Corrections due to Wahl and Woods are incorporated in the formulæ, and finally two nomograms, for stress and deflexion calculations respectively, are produced to enable these involved formulæ to be handled easily and rapidly.

Consideration is given to physical properties, and it is pointed out that except for special conditions of service, the torsional elastic limit of the material is the most important physical property of the material in most helical tension and compression springs. Data are given for this property for patented carbon spring steel and for chromium-vanadium spring steel. Tolerances and limiting conditions are considered, and an arbitrary figure of 70 per cent of the torsional elastic limit is adopted as the maximum safe stress. Curves of load-carrying capacity are given for all standard gauges from 0·020 to 0·50 inch diameter-Special service conditions are finally considered, and suggestions made for dealing with them. In an Appendix are given various examples illustrating the use of the curves and nomograms, and the derivation of some special formulæ.
Stage Efficiency, Cumulative Heat, and Reheat Factor of Steam Turbines
Authors: Smith D. M.
Published: October 2007

The paper discusses methods of calculation of stage efficiency, cumulative heat, and reheat factor for a given steam turbine condition curve, together with the converse problem of the determination of the condition curve and reheat factor when the stage efficiency is given. The complications due to pressure loss, resuperheating and tapping for feed heating are considered. A set of graphs calculated by these methods is provided for reading off the relations between turbine efficiency, stage efficiency, and reheat factor with condition curves based on constant dry stage efficiency of small stages and standard wetness loss correction (1 per cent loss per 1 per cent wetness).
Deformation and Fracture of Mild Steel Under Cyclic Stresses in Relation to Crystalline Structure
Authors: Gough H. J. , Wood W. A.
Published: October 2007

The paper describes an extension of a recent research into the characteristics of the deformation and fracture of metals under static and fatigue stressing as revealed by precise methods of X-ray diffraction. The four series of fatigue tests were designed specially to take into consideration the cases where the upper stress of the cycle is in the immediate neighbourhood, first, of the ultimate tensile strength, and second, of the static yield point of the material. Accurate records have been made throughout of the changes in shape of the specimen. The structure has been examined by the X-ray method at the end of the test in every case, and also, in certain cases, at various interrupted stages.

The results have shown that, in general, the observed changes in structure, even under the most critical conditions of stress, are similar in nature to those found in the previous work. It has also been established that, under a safe range of stress, the damage to the structure is equivalent to that caused by a single sustained application of a static stress equal in amount to that of the maximum stress of the cycle. Further, the additional and progressive damage caused by cycles of an unsafe range of stress leads to a complete fragmentation of the whole or part of the specimen. Finally, the results of the complete series of alternating and pulsating direct stresses have been reviewed in relation to the deformation in the specimen; the conclusion is reached that, though complicating factors are present, the average stress of the cycle appears to have only a small effect on the fatigue resistance of the material.
The Problem of Economic Foundry Production
Authors: Ronceray Eugène
Published: October 2007

The paper describes methods of obtaining the greatest efficiency in the foundry by the simplest possible means, a principle of the first importance. The author has had forty years' experience of foundry practice, during which he has often changed his opinion on particular points, as requirements have grown, and as the means of realizing them have developed.

Economy in transport in the foundry depends on sound organization of methods. The preparation and stocking of sand are of no less importance. Continuous discharge from the sand mill is advocated, and the various means of transporting and handling the sand are described, and the suitability or otherwise of different types of apparatus discussed. Mould conveyers and the positions of the moulding machines relative to them are also considered. The conclusion is drawn that with care the simplest plants can be profitably mechanized.