bluuebunny/crossref_metadata_2025 huggingface dataset:
Engine Development Under the Ministry of Aviation
Authors: Lloyd Peter
Published: June 2018

The seven year life of the Ministry of Aviation was a time of dramatic change, not only in engine technology, but also in defence and procurement policy, in industrial organisation and in the public image of the aircraft industry. The rapid increase in the cost of developing and producing new aircraft and weapon systems made development management and cost control issues of the greatest importance and much effort was devoted to devising improved management procedures. In summarising the technological achievements of the period, attention is particularly drawn to changes in engine noise characteristics, in selling price and in the growth of overhaul life and reliability. The nature of engine development is examined in some detail and it is pointed out that the development content of engine programmes is normally much greater than that of airframe programmes. The high development effort and expenditure demanded by aero engines is explained and justified. Attention is drawn to the relationship between development cost and (a) manufacturing cost, (b) the magnitude of technical advance.

Some of the problems encountered in the search for an effective system of cost estimation and control are indicated.
Optimal Space Trajectories—A Review of Published Work
Authors: Bell D. J.
Published: June 2018

The problem of transferring a space vehicle between two points in a given gravitational field such that the minimum amount of fuel is used has been called the fundamental navigational problem of astronautics. In such a problem it may be required to find the optimum thrust magnitude and thrust direction which yields a minimum fuel trajectory. Furthermore, certain end conditions may be specified which the optimal trajectory must satisfy. In a large number of published papers the velocity of the vehicle is supposed known both at the beginning of the transfer and at the end whereas the time taken to complete the manoeuvre may or may not be given. Also, other performance criteria have been chosen besides minimum fuel. For example, minimum time of transit or maximum orbital altitude at perigee.

Papers mentioned in this review deal mainly with flight in two dimensions apart from those sections on general theory. Furthermore, all space vehicles considered are assumed to have a fixed exhaust velocity unless otherwise stated.
A New Phase in Aviation?
Authors: Cockburn Robert
Published: June 2018

Aviation has become a great international utility, and as the scale of investment has grown innovation is increasingly dominated by economic considerations. The time needed to bring research, development and design to fruition is lengthening and economic and technical trends must be appraised tor many years ahead. Of the various parameters defining aircraft design and performance, speed is the most fundamental. The speeds of both military and civil aircraft have been doubling every decade for over 50 years; but the factors which contributed to this exponential growth have changed and a new basis for prediction must be established.

Above high subsonic speed transport efficiency remains sensibly constant although with pronounced optima around Mach 0.8 and Mach 3. In future, aircraft will tend to fall into distinguishable speed regimes; but application will be determined by their economic productivity rather than by small differences in transport efficiency. Subsonic aircraft will remain the mainstay of civil and military aviation for many years, with supersonic aircraft meeting a growing civil demand on the longer international routes and military requirements tor fighters, bombers and reconnaissance aircraft. In neither field is there any imminent demand for hypersonic aircraft.

But if the quest for higher speed is no longer the dominant incentive in aeronautics, there are new in:tiatives at the low speed end of the flight envelope, and continued improvements are foreseeable in the efficiency of propulsion, structure, and avionics. If these opportunities are seized there is a challenging and rewarding future for European aviation.
Fifty Years of Engineering Learning
Authors: Banks F. R.
Published: June 2018

It is always an honour to be invited to give a lecture, and particularly a memorial lecture to a man so outstanding in his own field.

I knew Roy Chadwick and liked him. I admired, too, his working ability and his professionalism. He was a natural born designer, and I need not list here his attainments and successes since these were very adequately dealt with by Rogerson in the First Memorial Lecture to him.

I thought long about the subject of my talk this evening and finally decided that, at my time of life, it might be appropriate if I were to give a sketch of my accumulated experience, and experiences, over more than fifty active years—divided between marine diesel engines and automobile and aviation engines.
Subsonic Aircraft Drag: An Appreciation of Present Standards
Authors: Haines A. B.
Published: June 2018

The drag at cruise CL of a number of recent aircraft—mostly large subsonic transports—has been analysed in terms of figures-of-merit derived from Melvill Jones’ original concept of a streamline aeroplane. The values have been compared with those for some representative aircraft from the 1930-1940 period. The paper then proceeds to highlight some of the main sources of excess drag; for the recent aircraft, these are grouped under broad headings such as “excrescences”, “Mach-number effects” and “nacelle installation or interference”.

The results of the analysis are somewhat disturbing. Perhaps the most striking feature, bearing in mind that only a restricted class of aircraft have been considered, is the very wide spread between the figures for the poorest and the best of the recent aircraft. Also, the detailed drag breakdown varies widely from one aircraft to another. The evidence in the paper suggests that, in many cases, present drag standards can and should be improved.
The Jumbo Jet and Public Safety
Authors: Lederer Jerome
Published: June 2018

In late September 1967, Her Majesty Queen Elizabeth II of Great Britain launched a new Cunard ocean liner in Scotland with the phrase, “Every great enterprise has an element of risk and uncertainty about it and I am sure no one can predict the future of our venture.” The launching of any new aircraft carries a similar connotation. For the jumbo jet as for the ocean liner, the risks should be recognised and, therefore, minimised because both the building of the ocean liner and the jumbo jet are extensions of a known art, not an introduction to unknown ventures such as may be true of the SST.

Size is relative. In its day, the DC-3 was called the “giant” air liner. If one compares the 21 passenger DC-3 with the 250 passenger DC-8, a twelve-fold increase, one can say that we are already in the jumbo jet age. The transition has been gradual through the Stratoliners, the DC-4, the DC-6, the Constellation, DC-7, Britannias, Vanguards, Caravels, Convairs, 707’s, and others. The results have been dramatic. (Fig. 1.)
Part II-Implementing Strategic Plans, Operational Planning and Control
Authors: Norman P. A.
Published: June 2018

The first part of this paper, published in the May JOURNAL, discussed in general terms certain topics relevant to business objectives and industry orientation and dealt in some detail with definition of company objectives and strategic plans. The successful completion of this first phase is dependent on close co-operation between Government and Industry for both civil and military projects.

This part of the paper deals with the procedures for implementing the strategic plan (management control) and the application and control at operational levels (operational control). The phase of implementation is one where considerable scope exists for ensuring future effectiveness through sound direction in that the plan becomes a firm commitment at this stage.

The paper concludes with a brief summary and a list of recommendations for future activities within the Management Studies Group of the Society aimed at definition of a basis for application of the disciplines described in the paper.
The Effect of Condensation on Hypersonic Laminar Heat Transfer to Cones
Authors: Wood N. B.
Published: June 2018

The investigation of Daum focused attention on the problem of condensation in hypersonic wind tunnels. In such tunnels there is often a conflict between the desire to obtain the maximum Reynolds number and the necessity of operating with a sufficiently high stagnation temperature to avoid liquefaction of the working gas. The hypersonic gun tunnel, in which the present tests were made, is capable of running at relatively high Reynolds numbers and to define the operating limits of the RARDE gun tunnel, Bowman made measurements similar to those of Daum, but using nitrogen as the working gas. It will be recalled that Daum made measurements of static and pitot pressures at varying temperatures. He deduced from these measurements that below a certain working section pressure significant degrees of supersaturation could be tolerated before breakdown to the condensed state. Thus three regions can be defined; in order of increasing temperature these are:

(i) condensing flow;

(ii) supersaturated uncondensed flow; and

(iii)unsaturated flow (see Fig. 1).
Coupled Vibration of Geared Systems
Authors: Mahalingam S.
Published: June 2018

In the design of geared rotating systems in engineering practice a variety of configurations are used, and their torsional vibration has been extensively studied. Detailed analyses of the modes and frequencies of vibration of these systems have been given by Ker Wilson and Nestorides. When the rotating system is rigidly supported, standard methods may be used to obtain the characteristics of free vibration and the response to impressed forces, from which the transmissibility of the gear-box may be calculated. However, there are many applications in which the gearbox is flexibly mounted. The simple example of a geared engine with a flexibly mounted crankcase has been considered by Den Hartog and Butterfield. In some epicyclic gear-box assemblies, elastic elements are introduced between the reactive element and the gear-case to increase the capacity for absorbing impulsive loads and as a means of varying the natural frequencies of vibration'. Harmonic forces acting on the rotors excite coupled vibration of the rotating system and the supporting frame, and Ker Wilson has shown how the natural frequencies and modes of the combined system may be determined by Holzer-type tabular methods. This involves a trial-and-error technique which may sometimes be tedious. Vibration of geared systems may also be excited by the motion of the frame supporting the gear-box, and an analysis of the response is necessary in the determination of dynamic loads.
The Calculation of Aerodynamic Forces and Pressures on Wings Entering Step Gusts
Authors: Mitchell C. G. B.
Published: June 2018

Lifting surface computer programs now exist for calculating the air forces on oscillating wings of general planform. These have made it practicable to evaluate the transient forces on wings entering step gusts by using a long-established relation between oscillatory and indicial forces. As examples, the indicial forces on a low aspect ratio wing in incompressible flow and the indicial pressures on a delta wing at a low subsonic Mach number are calculated. In the latter case the calculated results, which are based on attached flow, are compared with measurements on the same wing in conditions of separated flow. Despite the differences in flow, surprisingly similar development histories are found.
The ELDO-PAS Programme and Its Management
Authors: Nouaille J.
Published: June 2018

The purpose of this paper is:

1. To describe the technical content of the ELDO-PAS Programme;

2. To give an outline of the management procedures used by the ELDO Secretariat.

The presently approved ELDO programmes are:

(a) The Initial Programme as described by the ELDO Convention aiming at the development of the threestage Europa I Launcher.

(b) The Supplementary Programme approved by ELDO Member State Ministers in July 1966 to give ELDO the capability of placing significant payloads in geo-stationary orbits.
Operations Research in Aer Lingus
Authors: Foley Maurice A.
Published: June 2018

This paper is based on a lecture given to a meeting in June 1967 sponsored by the Royal Aeronautical Society and Business Operations Research Ltd. It describes the activities of the operations research functions in Aer Lingus and is based on the work both of the central Operations Research Unit and, also, on studies carried out by management science specialists in the Aer Lingus Economic Planning Department.
Circulation Control and its Application to Stopped Rotor Aircraft
Authors: Cheeseman I. C.
Published: June 2018

The problems associated with the design of a stopped rotor aircraft are summarised. The decision to attempt to overcome the aerodynamic difficulties by the choice of a rotor blade section which is basically insensitive to atmospheric gusts dictates a largely circular cross section. During the rotor lifting phases of the flight the circular section is constrained to lift by a technique called circulation control by blowing — this technique is described and some results presented. A scale model hingeless rotor has been tested at the National Gas Turbine Establishment. Typical performance figures are presented and their implications discussed. In particular, it is shown that operating rotors at high values of thrust coefficient per blade leads to high induced power factors. Cyclic control of rotor lift is achieved by hub throttling the air to the circulation control slots —a simple mechanism to achieve this result is described. Two possible schemes for a VTOL circulation control stopped rotor transport are discussed and compared.
The Effect of Air Traffic Control Policy on the Growth of Aviation
Authors: Goodhart H. C. N.
Published: June 2018

Much of what I am going to say is opinion and many will find it controversial. It is therefore essential to start off from a firm and incontrovertible basis of fact. By this means it should be possible to narrow down the controversy considerably.

Table I represents the state of aviation in this country in comparison with the USA. These facts are confined to civil aviation since it is the growth of civil aviation that I am talking about.
Commercial Operation of Helicopters
Authors: Bristow A. E.
Published: June 2018

It is a great privilege for me to give the Eighth Cierva Memorial Lecture and to pay tribute and honour to Juan de la Cierva who, more than any other inventor, was responsible for bringing into reality the principle of rotating wing flight. Cierva was an inventor of indefatigable industry, patience and genius. His faith in the Autogiro and the future of the rotating wing aircraft will be remembered for ever.

The invention by Cierva of the articulated rotor with flapping and drag hinges to relieve bending stresses at the blade root, and in the chord-wise plane, provided the solution to true helicopter flight which become a reality in 1936.
Thunderstorm Project
Authors: Patrick K. B.
Published: June 2018

The thunderstorm was a hazard which had still not been investigated at the end of the war, a hazard that had caused many serious aircraft accidents. No longer could the old admonition to stay out of thunderstorms be strictly followed by commercial or military pilots, whose flights could not be restricted to fair weather so as to avoid the severe turbulence occurring inside most thunderstorms.

This led to the ‘Thunderstorm Project’ in the USA in 1946-47 in Florida and Ohio'. Since the hazardous features of a thunderstorm are associated with individual cells, it is important for an understanding of the storm as it affects flight operations, to be aware of the nature of these features and their variation with stages of cell development.
Roll Dynamics of a Spinning Axi-Symmetric Satellite using the WKBJ Method
Authors: Modi V. J. , Neilson J. E.
Published: June 2018

The attitude dynamics of a spinning axi-symmetric satellite, free to librate in roll, is studied using the WKBJ method. Applicability of the method to the linearised equation of motion is first verified. To facilitate the evaluation of the WKBJ solution and to make it more amenable to the phase space analysis, second order terms in eccentricity are neglected. The form of the solution suggests the presence of phase and amplitude modulation effects for non-circular orbits. The comparison between the WKBJ analysis and ‘exact’ numerical solutions showed that the approximate analysis predicts the period and amplitude of motion with an accuracy adequate for the preliminary design purposes.
Review of V/STOL Aircraft with Tilt-Propellers and Tilt-Rotors
Authors: Borst Henry V.
Published: June 2018

Tests of the first experimental VTOL aircraft using tiltable wings and propellers indicated that practical operational aircraft are possible and can operate with a high degree of effectiveness.

The flight tests accomplished up to the present time with the second generation tilt-propeller and tilt-rotor aircraft are discussed and analysed. The XC-142 and the CL-84 tilt-wing aircraft have been performing well throughout their projected flight envelope and good pilot ratings have been obtained with each in hover, transition, and the normal cruise mode. The X-19 tandem wing tilt propeller was flown only up to 100 knots and was lost due to a structural failure in one nacelle. Although the operation of the aircraft had been satisfactory up to this point, this programme was terminated due to shortage of funds.

A study of the various VTOL aircraft configurations operating at low radius of action indicates that the tilt wing/ tilt propeller type are the most cost-effective as long as speed is an important parameter in the operating mission. There are missions where speed is of secondary importance, and therefore, the helicopter will continue to be one of the most effective VTOL for these missions.

Since the tilt-wing /tilt-rotor aircraft tend to be only slightly higher in cost than the helicopter and with development the complexity and maintainability will be reduced to acceptable levels, it is anticipated that further work will be done in the development of these vehicles, and successful and useful machines will be built in the future.
The Second Century Papers: Looking Ahead in Aeronautics—10
Authors: Melvill Jones G.
Published: June 2018

In the first contribution to “Looking Ahead in Aeronautics” Dr. Küchemann writes “The task of viewing the prospects over a whole century may be regarded as being at once impossible, presumptuous and not without a touch of the absurd”, which lies close to the first response of the present author. But on reflection, the very impossibility of reliable prediction a century ahead surely stands to change the tune somewhat. Over this large time-scale, bold flights of fancy into the unknown must take equal place with cautious realism and an author may presume to feel released from some at least of his usual conditioned restraints. In turn, yielding of constraint strengthens the writer's arm, until, not without a certain sense of trepidation, one is at length tempted to plunge into the guessing pool along with a goodly company of fellow men.
Structural Testing
Authors: Underwood G. W.
Published: June 2018

Structural testing has always been an art as well as a science but never more so than at present. Even though knowledge in relation to design and stressing has increased, testing is still a vital feature. This increase in knowledge has been accompanied by more complex problems particularly in relation to the need for environmental testing with the advent of supersonic and hypersonic aircraft, VTOL aircraft, rockets, guided missiles and space vehicles.
The Second Century Papers: Looking Ahead in Aeronautics—11
Authors: Stanton-Jones R.
Published: June 2018

The introduction to a book called “An Anthology of Partly Baked Ideas” states that it was compiled to provide an opportunity for the publication of ideas either half or partly baked, which might not otherwise be suitable for publication in established learned journals.

However, the Royal Aeronautical Society's decision to solicit articles on aeronautical achievement in the latter half of the twenty-first century is a direct invitation from a learned society to expound on, what at best, can only be some very partly baked ideas.

The author of this admirable anthology, I. J. Good, has defined partly baked ideas (PBIs) in some detail in the opening chapters where he gives a clear indication that reputable scientists and engineers should at very least endeavour to incubate their proposals to the point where the degree of “bakedness” should be greater than 0·5, i.e. better than half-baked.
The Second Century Papers: Looking Ahead in Aeronautics—12
Authors: Hearne P. A.
Published: June 2018

In considering the spectrum of possibilities which advances in electronics offers during the next fifty years it is worth a short backward glance over an equal time span.

In 1918 the use of electronics was almost entirely devoted to developments in the radio frequency field, principally those of communication and sound amplification. Wireless telegraphy under pressure from naval and merchant marine requirements had reached the stage where it formed a dependable means of communication, albeit with the need for specialised human skills, for the world's modern shipping.

There had been a limited amount of aeronautical radio development during the war, to reduce the size and weight of wireless telegraphy and the later radio telephony transmitters; much of the later stages of this work was carried out at Biggin Hill. However, these developments had scarcely any influence upon either the design and construction of aircraft or perhaps more important only a small influence on their operation. It was to be sometime before the exploitation of the radio frequency spectrum on the ground and in the air contributed to increase greatly the operational capability of the aeroplane during the 1930's.
Kinetic Heating of Aircraft Structures
Authors: Taylor J.
Published: June 2018

The design of aircraft subjected to kinetic heating is the same as any other structural problem. First, the loading condition must be determined, then the structure has to be designed to withstand that condition and finally the design must be confirmed by test. This lecture follows this pattern and does so in the same order.

The source of the energy that is transferred to the structure is the aerodynamic boundary layer and a study of the boundary layer forms the main part of the lecture. During the past few years a large amount of work has been done and the Society is proposing to issue Data Sheets this year to replace those issued in 1955. The same work forms the basis from which the present proposed values of heat transfer coefficients are obtained.
The New South Wales Air Ambulance
Authors: Walton Nancy-Bird
Published: June 2018

The Air Ambulance of New South Wales came into operation on Good Friday 1967. Less than sixteen months later as I write it has carried 2348 patients in 807 flights. Four hundred and eleven of these patients have been emergencies and it is highly probable that most of them would not have survived a long distance road journey. With few exceptions all patients have been sent in by country doctors for specialist treatment in the metropolitan area.

Introduced as an Air Arm to the excellent road ambulance service it was intended to avoid the road journeys for distances of more than 175 miles. In the first year it saved that service 932 760 road miles. The time that patients would have spent on the road was 16 201 hours, this was reduced by air to 3 094 hours.

It is hardly necessary to add what this means to a sick or injured person. Although deeply unconscious and in a state of shock patients have been transported without their condition deteriorating.
A Review of Hovercraft Research in Britain
Authors: Silverleaf A.
Published: June 2018

Almost exactly ten years ago the National Research Development Corporation (NRDC) decided to support Christopher Cockerell's ideas for what soon became known as hovercraft. Since then there have been remarkably rapid developments in marine hovercraft and in other applications of the air cushion principle, and there is little need to remind this audience of what has been achieved during that time. Indeed, the large cross-Channel SRN4, and the smaller new Hovermarine sidewall craft, as well as the recently announced design by Vosper-Thornycroft, all speak for themselves and demonstrate vividly the major strides that have been made within a single decade.

During this period there has naturally been a strong emphasis on development work closely related to specific engineering and design projects, but experimental and theoretical investigations of a more general and basic nature have also been encouraged in this country. It is always difficult to separate clearly research from development and this is particularly so in the first decade of hovercraft.
The Heat Transfer Performance of Porous Gas Turbine Blades
Authors: Bayley F. J. , Turner A. B.
Published: June 2018

It is well known that the performance of the practical gas turbine cycle, in which compression and expansion are non-isentropic, is critically dependent upon the maximum temperature of the working fluid. In engines in which shaft-power is produced the thermal efficiency and the specific power output rise steadily as the turbine inlet temperature is increased. In jet engines, in which the gas turbine has so far found its greatest success, similar advantages of high temperature operation accrue, more particularly as aircraft speeds increase to utilise the higher resultant jet velocities. Even in high by-pass ratio engines, designed specifically to reduce jet efflux velocities for application to lower speed aircraft, overall engine performance responds very favourably to increased turbine inlet temperatures, in which, moreover, these more severe operating conditions apply continuously during flight, and not only at maximum power as with more conventional cycles.
Operational Aspects of the Supersonic Transport
Authors: Abell C.
Published: June 2018

Frank Barnwell was a man who combined vision with practical achievement and as such earned tremendous respect. I am sure he would have enjoyed the challenge, as well as the vision, of further shrinking Everyman's World by making Supersonic Transport a commercial reality.

I am indeed honoured in being asked to give this 1968 lecture in his memory.

Right at the start I would like to pay tribute to all of my colleagues who have done a great deal of work preparing the material for this paper, and to say that without their help it would not have been an interesting paper at all.
A Note on the Accuracy of Similar Solutions of the Equations for Laminar Boundary Layers on Curved Surfaces
Authors: Massey B. S. , Clayton B. R.
Published: June 2018

To describe steady, two-dimensional, constant-density flow in a laminar boundary layer on a curved surface, a single equation may be derived from the complete Navier-Stokes equations, with no approximations being necessary. The conditions under which similar solutions are attainable are discussed, and the validity of some previous calculations is upheld.
The Shipper's Aspect of
Facilitation
Authors: Hope Archibald
Published: June 2018

Annex 9 to the Convention on International Civil
Aviation is entitled “Facilitation” and in the
foreword to the fifth edition there is what might be
termed a definition of facilitation … “all practical
measures, through the issuance of special
regulations or otherwise, to facilitate or expedite
navigation by aircraft between the territories of
Contracting States, and to prevent unnecessary
delays to aircraft, crews, passengers and cargo,
especially in the administration of the laws
relating to immigration, quarantine, customs and
clearance”. I am here to give a shipper's view of
facilitation and therefore, am concerned only with
cargo. I hope my views are not coloured by
experiences I have had as crew or passenger which
tend to be much more personal and immediate.
Air Reconnaissance in the Royal Air Force
Past, Present and Future
Authors: Crew E. D.
Published: June 2018

The lecture I am going to give attempts to cover, in
forty-five minutes a subject that really merits a
series of lectures. This, of course, displays a
fitting disregard for minor difficulties, of which,
I am sure, the dauntless spirit of Sir George Cayley
would have approved.

The broad title permits consideration of all methods of
intelligence gathering from the air, including the
more widely known optical photographic systems, and
has been deliberately selected for this purpose. To
avoid clumsy and longwinded definitions I will
frequently have recourse to the the use of “in”
terms such as Sensor, Multi-Sensor, Exploitation,
Environment and many others.
Small Aero-Engines—Past, Present and Future
Authors: Moult E. S.
Published: June 2018

Before I begin, may I say how much I appreciate the honour of being invited by the Derby Branch of the Royal Aeronautical Society to give this Lecture. It is now eleven years since Mr. Evernden gave us the story of Henry Royce himself and an account of the idealism and inspiration which laid the foundations of the great firm that bears his name. Mindful of this and of the accomplishments of my predecessors, I approach my task in a spirit of great humility.
Forward Speed Effects on Annular Jet Cushions
Authors: Alexander A. J.
Published: June 2018

Simple two-dimensional theory is extended to the case of a hovercraft having forward speed. It is shown that in general the effect of forward speed on lower surface lift is adverse but that the static pressure in the region of the rear jet has an important influence and if this pressure is low and hit is also low some reduction in lift power is achieved.
The tissue profile of metabolically active coenzyme forms of vitamin B12 differs in vitamin B12-depleted rats treated with hydroxo-B12 or cyano-B12
Authors: Greibe Eva , Kornerup Linda S. , Juul Christian B. , Fedosov Sergey N. , Heegaard Christian W. , Nexo Ebba
Published: June 2018

Recent rat studies show different tissue distributions of vitamin B12 (B12), administered orally as hydroxo-B12 (HO-B12) (predominant in food) and cyano-B12 (CN-B12) (common in supplements). Here we examine male Wistar rats kept on a low-B12 diet for 4 weeks followed by a 2-week period on diets with HO-B12 (n 9) or CN-B12 (n 9), or maintained on a low-B12 diet (n 9). Plasma B12 was analysed before, during and after the study. The content of B12 and its variants (HO-B12, glutathionyl-B12, CN-B12, 5'-deoxyadenosyl-B12 (ADO-B12), and methyl-B12 (CH3-B12)) were assessed in the tissues at the end of the study. A period of 4 weeks on the low-B12 diet reduced plasma B12 by 58 % (from median 1323 (range 602–1791) to 562 (range 267–865) pmol/l, n 27). After 2 weeks on a high-B12 diet (week 6 v. week 4), plasma B12 increased by 68 % (HO-B12) and 131 % (CN-B12). Total B12 in the tissues accumulated differently: HO-B12>CN-B12 (liver, spleen), HO-B12<CN-B12 (kidneys), and HO-B12≈CN-B12 (brain, heart). Notably, more than half of the administered CN-B12 remained in this form in the kidneys, whereas HO-B12 was largely converted to the bioactive ADO-B12. Only <10 % of the other cofactor, CH3-B12, were found in the tissues. In conclusion, dietary CN-B12 caused a higher increase in plasma and total kidney B12 but provided less than half of the active coenzymes in comparison to dietary HO-B12. These data argue that HO-B12 may provide a better tissue supply of B12 than CN-B12, thereby underscoring the lack of a direct relation between plasma B12 and tissue B12.
Metabolic responses to high-fat diets rich in MUFAv. PUFA
Authors: Polley Kristine R. , Miller Mary K. , Johnson Mollie , Vaughan Roger , Paton Chad M. , Cooper Jamie A.
Published: June 2018

Dietary fatty acid (FA) composition may influence metabolism, possibly affecting weight management. The purpose of this study was to compare the effects of a 5-d diet rich in PUFAv. MUFA. A total of fifteen normal-weight men participated in a randomised cross-over design with two feeding trials (3 d lead-in diet, pre-diet visit, 5-d PUFA- or MUFA-rich diet, post-diet visit). The 5-d diets (50 % fat) were rich in either PUFA (25 % of energy) or MUFA (25 % of energy). At pre- and post-diet visits, subjects consumed breakfast and lunch test meals, rich in the FA for that 5-d diet. Indirect calorimetry was used for 4 h after each meal. There were no treatment differences in fasting metabolism acutely or after the 5-d diet. For acute meal responses before diet, RER was higher for PUFAv. MUFA (0·86 (sem0·01)v. 0·84 (sem0·01),P<0·05), whereas diet-induced thermogenesis (DIT) was lower for PUFAv. MUFA (18·91 (SEM1·46)v. 21·46 (SEM1·34) kJ,P<0·05). After the 5-d diets, the change in RER was different for PUFAv. MUFA (−0·02 (sem0·01)v. 0·00 (sem0·01),P<0·05). Similarly, the change in fat oxidation was greater for PUFAv. MUFA (0·18 (sem0·07)v. 0·04 (sem0·06) g,P<0·05). In conclusion, acutely, a MUFA-rich meal results in lower RER and greater DIT. However, after a 5-d high-fat diet, the change in metabolic responses was greater in the PUFA diet, showing the metabolic adaptability of a PUFA-rich diet.
EFFICIENCY OF IRRIGATED AND RAIN-FED RICE (ORYZA SATIVA) PRODUCERS IN FADAMA AGRICULTURE, NIGERIA
Authors: OPATA PATIENCE IFEYINWA , NWEZE NOBLE JACKSON , EZEIBE ADAKU BRIGET , MALLAM MAMUN
Published: June 2018

Given the importance of irrigation for rice production, this study compared the technical efficiency of irrigated and rain-fed rice (Oryza sativa) farms in the Upper Niger River Basin and Rural Development Authority (UNRBDA), Nigeria. Primary data were collected from 300 irrigators and 325 rain-fed rice producers. Applying the stochastic frontier Cobb–Douglas production function, net income analysis and Likert scale rating techniques, the study found that irrigated scheme increased marginal factor productivity and profitability. The study revealed the existence of large technical inefficiency in rain-fed farms when compared with irrigated farms. This suggests that there is room for output gains through technical efficiency improvement in the rain-fed system. The mean value of the marginal physical product of inputs (VMPPX) in the irrigated farms (₦2.32) was more than that of rain-fed farm (₦1.67). Thus, if the average producers in the rain-fed are to achieve the technical efficiency level of the average producer in the irrigated farms, they can realize 38% output gains. Similarly, the mean net farm income (NFI) of ₦62,280.00 per ha in the irrigated farm was more than double of that of rain-fed farms ₦22,391.00. The partial regression coefficients for the individual production factors (β1) and (β3) for labour input (X1) and other variable inputs (X3), respectively, were positive and significant at 1% level, suggesting that the partial elasticity of crop output with respect to labour and other costs was higher in the irrigated farms than in the rain-fed farms. The Likert scale rating techniques showed that the poor knowledge of irrigation techniques, insufficient water for irrigation during the dry season, high cost of labour and lack of access to credit were the critical constraints preventing the rain-fed rice producer from joining the irrigation scheme. In view of this, rice irrigators should be encouraged to train more rain-fed farmers on some rudiments of irrigation techniques. They should also be linked to the sources of finance. Water Users Association (WUA) should be established in communities within the scheme areas for effective communication between farmers and the officials of the UNRBDA. Decision on the allocation of resources to Fadama sites including water should be given to WUA to strengthen the membership of the organization, while the government officials serve as supervisory and advisory body.
Commentary on Chris Turney's Why didn't they ask Evans?
Authors: May Karen
Published: June 2018

I am writing in response to Professor Chris Turney's recent research article Why didn't they ask Evans?, published in Polar Record on 28 September 2017. The article took as its focus Scott's second-in-command, Lieutenant E.R.G.R ‘Teddy’ Evans, and alleged that Evans failed to deliver Captain Scott's ‘updated orders’ to base in February 1912. This is an error that needs to be corrected.
INTERVAL VALUES AND RATIONAL CHOICE
Authors: Peterson Martin
Published: June 2018

Decision theorists have suggested that it is sometimes appropriate to represent the value of certain options as intervals of real numbers. In this note I show that doing so is incompatible with some deeply held intuitions about rational choice.
On the log-concavity of the sequence for some combinatorial sequences
Authors: Xia Ernest X. W.
Published: June 2018

Recently, Sun posed a series of conjectures on the log-concavity of the sequence , where is a familiar combinatorial sequence of positive integers. Luca and Stănică, Hou et al. and Chen et al. proved some of Sun's conjectures. In this paper, we present a criterion on the log-concavity of the sequence . The criterion is based on the existence of a function f(n) that satisfies some inequalities involving terms related to the sequence . Furthermore, we present a heuristic approach to compute f(n). As applications, we prove that, for the Zagier numbers , the sequences are strictly log-concave, which confirms a conjecture of Sun. We also prove the log-concavity of the sequence of Cohen–Rhin numbers.
A uniqueness result for a singular elliptic equation with gradient term
Authors: Carmona José , Leonori Tommaso
Published: June 2018

We prove the uniqueness of a solution for a problem whose simplest model is

with k ≥ 1, 0 f ∈ L∞(Ω) and Ω is a bounded domain of ℝN, N ≥ 2. So far, uniqueness results are known for k < 1, while existence holds for any k ≥ 1 and f positive in open sets compactly embedded in a neighbourhood of the boundary. We extend the uniqueness results to the k ≥ 1 case and show, with an example, that existence does not hold if f is zero near the boundary. We even deal with the uniqueness result when f is replaced by a nonlinear term λuq with 0 < q < 1 and λ > 0.
On linear independence measures of the values of Mahler functions
Authors: Väänänen Keijo , Wu Wen
Published: June 2018

We estimate the linear independence measures for the values of a class of Mahler functions of degrees 1 and 2. For this purpose, we study the determinants of suitable Hermite–Padé approximation polynomials. Based on the non-vanishing property of these determinants, we apply the functional equations to get an infinite sequence of approximations that is used to produce the linear independence measures.
Ghostbuster: A tool for simplifying and converting GADTs
Authors: ZAKIAN TIMOTHY A. K. , MCDONELL TREVOR L. , CIMINI MATTEO , NEWTON RYAN R.
Published: June 2018

Generalized Algebraic Data Types, or simply GADTs, can encode non-trivial properties in the types of the constructors. Once such properties are encoded in a datatype, however,allcode manipulating that datatype must provide proof that it maintains these properties in order to typecheck. In this paper, we take a step towardgradualizingthese obligations. We introduce a tool, Ghostbuster, that produces simplified versions of GADTs which elide selected type parameters, thereby weakening the guarantees of the simplified datatype in exchange for reducing the obligations necessary to manipulate it. Likeornaments, these simplified datatypes preserve the recursive structure of the original, but unlike ornaments, we focus on information-preserving bidirectional transformations. Ghostbuster generates type-safe conversion functions between the original and simplified datatypes, which we prove are the identity function when composed. We evaluate a prototype tool for Haskell against thousands of GADTs found on the Hackage package database, generating simpler Haskell'98 datatypes and round-trip conversion functions between the two.
Making Institutions and Context Count: How Useful Is Feminist Institutionalism in Explaining Male Dominance in Politics?
Authors: Adams Melinda , Smrek Michal
Published: June 2018

While the same formal candidate selection rules are generally in place throughout a state, there is often intracountry variation in male descriptive overrepresentation. To explain this variation, scholars cannot focus exclusively on women (e.g., how do women respond to formal institutional opportunities?) or femininity (e.g., how do norms governing appropriate female behavior affect women's odds of being selected as a candidate?). Rather, scholars must attend to the ways that informal norms regarding masculinity operate across space and time within a country. Drawing on the insights of feminist institutionalism, this essay examines two intracountry sources of variation in candidate selection: the spatial urban-rural divide and temporal differences between first-time recruitment and renomination. While the formal candidate selection rules are uniform, informal institutions vary depending on where and when we look, leading to different levels of male overrepresentation.
Rethinking Qualitative Methodology around Masculinity
Authors: Johnson Janet Elise , Rosenblum Darren
Published: June 2018

Given the predominance of men among elites, it is remarkable how little scholarship there is on the challenges of qualitative empirical work on elite men, especially work that interrogates the intersection of gender and class. We have both sought to include elite men as subjects, noting that the gender of our subjects, their social power, and our own gender performance have played a central role in defining our efficacy as researchers. Darren has researched top French corporate boards (e.g., Rosenblum and Roithmayr 2015). Janet has researched male dominance in the politics of Iceland and Russia (e.g., Johnson 2016; Johnson, Einarsdóttir, and Pétursdóttir 2013). This essay elaborates the challenges in researching elite men and explores the tactics we developed in response to the dynamic gender performances in the interviews, bringing Darren's insights as a legal scholar looking at economic elites to questions about male overrepresentation in politics.
Heritability of Hwabyung Symptoms in South Korean Adolescent and Young Adult Twins
Authors: Hur Yoon-Mi , Choi Eun-ji , Kim Jong-Woo , Jin Hee-Jeong , Lee Siwoo
Published: June 2018

The present study aimed to estimate heritability of Hwabyung (HB) symptoms in adolescent and young adult twins in South Korea. The sample included 1,601 twins consisting of 143 pairs of monozygotic male (MZM), 67 pairs of dizygotic male (DZM), 295 pairs of monozygotic female (MZF), 114 pairs of dizygotic female (DZF), and 117 pairs of opposite-sex dizygotic (OSDZ) twins and 129 twins with non-participating co-twins (mean age = 19.1 ± 3.1 years; range: 12–29 years). An HB symptom questionnaire was given to twins via a telephone interview. Consistent with the literature of HB, the mean level of HB was significantly higher in females than in males. Maximum likelihood twin correlations for HB were 0.31 (95% CI [0.16, 0.45]) for MZM, 0.19 (95% CI [-0.05, 0.41]) for DZM, 0.50 (95% CI [0.41, 0.58]) for MZF, 0.28 (95% CI [0.11, 0.44]) for DZF, and 0.23 (95% CI [0.05, 0.40]) for OSDZ twins. These patterns of twin correlations suggested the presence of additive genetic influences on HB. Model-fitting analysis showed that additive genetic and individual-specific environmental influences on HB were 44% (95% CI [37, 51]) and 56% (95% CI [49, 63]), respectively. Shared environmental influences were not significant. These parameter estimates were not significantly different between two sexes, and did not change significantly with age in the present sample, suggesting that genetic and environmental influences on HB in both sexes are stable across adolescence and young adulthood.
Soybean Flower and Pod Response to Fomesafen, Acifluorfen, and Lactofen
Authors: Beam Shawn C. , Flessner Michael L. , Pittman Kara B.
Published: June 2018

Diphenyl ether herbicides are commonly applied POST in soybean to control weeds late in the growing season that have not been controlled by other previous weed management tactics. These “rescue” applications can occur during reproductive soybean growth. The effect of these herbicides on the developing flowers and pods is not known. Field research studies were conducted over 3 yr to determine how soybean flowers and developing pods respond to fomesafen, acifluorfen, and lactofen when applied at R1, R3, and R5 growth stages. Flower and pod counts in the nontreated check showed an increase (17.1, 5.8, and 2.21 at R1, R3, and R5 stage, respectively) and were statistically the same as the herbicide treatments 1 wk after treatment. Fomesafen, acifluorfen, and lactofen applied at 395, 420, and 219 g ai ha–1 at R1, R3, and R5 stage had no negative impact on soybean flowers and developing pods when compared to the nontreated check. No significant differences were observed in soybean yield between any treatments in all site-years of the study.
Ageism Affects the Future Time Perspective of Older Adults
Authors: Barber Sarah J. , Tan Shyuan Ching
Published: June 2018

Abstract. These studies tested whether ageism affects the future time perspective (FTP) of older adults. Ageism occurs when someone is classified as “old” and is judged or treated differently as a result. To mimic this, we recruited participants (aged 50+) from Amazon’s Mechanical Turk. We made their age salient, exposed them to negative aging stereotypes, and asked them to complete Carstensen and Lang’s (1996) FTP Scale. Across multiple studies, participants assigned to the ageism conditions rated their futures as having fewer opportunities. This effect was mediated by mood and did not occur for younger adult participants. In addition, as the personal experiences of older adults with ageism increased, their perception of futures opportunities decreased. Thus, ageism reduces the future opportunities older adults see for themselves.
Forcing Single‐Column Models Using High‐Resolution Model Simulations
Authors: Christensen Hannah M. , Dawson Andrew , Holloway Christopher E.
Published: June 2018

To use single‐column models (SCMs) as a research tool for parameterization development and process studies, the SCM must be supplied with realistic initial profiles, forcing fields, and boundary conditions. We propose a new technique for deriving these required profiles, motivated by the increase in number and scale of high‐resolution convection‐permitting simulations. We suggest that these high‐resolution simulations be coarse grained to the required resolution of an SCM, and thereby be used as a proxy for the true atmosphere. This paper describes the implementation of such a technique. We test the proposed methodology using high‐resolution data from the UK Met Office's Unified Model, with a resolution of 4 km, covering a large tropical domain. These data are coarse grained and used to drive the European Centre for Medium‐Range Weather Forecast's Integrated Forecasting System (IFS) SCM. The proposed method is evaluated by deriving IFS SCM forcing profiles from a consistent T639 IFS simulation. The SCM simulations track the global model, indicating a consistency between the estimated forcing fields and the true dynamical forcing in the global model. We demonstrate the benefits of selecting SCM forcing profiles from across a large domain, namely, robust statistics, and the ability to test the SCM over a range of boundary conditions. We also compare driving the SCM with the coarse‐grained data set to driving it using the European Centre for Medium‐Range Weather Forecast operational analysis. We conclude by highlighting the importance of understanding biases in the high‐resolution data set and suggest that our approach be used in combination with observationally derived forcing data sets.