bluuebunny/crossref_metadata_2025 huggingface dataset:
Terson Syndrome in Patients with Aneurysmal Subarachnoid Hemorrhage: A 10-Year Single-Center Experience
Authors: Göttsche Jennifer , Knospe Volker , Sauvigny Thomas , Schweingruber Nils , Grensemann Jörn , Spitzer Martin S. , Westphal Manfred , Skevas Christos , Czorlich Patrick
Published: March 2023

Background

Terson syndrome (TS), an intraocular hemorrhage associated with aneurysmal subarachnoid hemorrhage (aSAH), occurs in up to 46% of all patients with subarachnoid hemorrhage. Despite its high incidence, TS is underrepresented in the literature, and patients with aSAH are sometimes not systematically evaluated for the presence of TS in clinical practice. This work aims to raise awareness of TS, reevaluate previous scientific findings, describe risk factors associated with the occurrence of TS, and present our local diagnostic and treatment concept.

Methods

All patients with aSAH treated at our institution between October 2010 and May 2020 were included in this retrospective study. The frequency of ophthalmological screening by indirect funduscopy, as well as the results, was investigated. In addition, the collection and statistical analysis of epidemiological and clinical data was performed using χ2, Kruskal–Wallis, and analysis of variance testing; multivariate regression; and receiver operating characteristic analysis. The significance level was set at p < 0.05.

Results

A total of 617 patients were treated for aSAH in our institution. Of these, 367 patients (59.5%) were ophthalmologically examined for the presence of TS. The rate of TS in the examined patients was 21.3% (n = 78). Patients with TS had significantly higher Fisher and World Federation of Neurosurgical Societies (WFNS) scores (p < 0.0001). Regression analyses showed WFNS grade (p = 0.003) and the occurrence of seizures (p = 0.002) as independent predictors of TS, as did receiver operating characteristic analyses, which had a significant area under the curve of 0.66 for the combination of WFNS grade and seizures. For 12 (15.4%) patients, the TS had to be surgically treated by pars plana vitrectomy in a total of 14 eyes, which resulted in significant improvement of visual function in all patients: mean preoperative best-corrected visual acuity was 0.03 (± 0.08) versus 0.76 (± 0.21) postoperatively (p < 0.001).

Conclusions

TS is a common complication in patients with aSAH, affecting approximately one in five patients. A higher WFNS grade and the occurrence of seizures are associated with TS; therefore, screening for TS should be performed in these patients.
Limits to blue economy: challenges to accessing fishing livelihoods in Ghana’s port communities
Authors: Ayilu Raymond K.
Published: March 2023

The blue economy concept has drawn global attention to the maritime economy, recognising expanding maritime industries such as shipping as crucial drivers of economic growth. In recent decades, seaports have correspondingly witnessed significant expansion, allowing them to play a substantial role in achieving blue growth. This study examines the challenges faced by small-scale fishing actors in gaining access to fishing livelihoods in coastal fishing communities close to Ghanaian ports. Drawing on political ecology, the study demonstrates how securitisation in port areas and dispossession has resulted in unstable fishing livelihoods in port communities. The study shows that the growth-oriented goals of port expansions and port security measures have restricted fishing communities’ access to coastal fishing spaces and caused congestion in the canoe bays of Ghana’s fishing harbours. In addition, the urbanisation around the ports has impacted fishers’ ability to meet the rising cost of living in fishing communities with fishing incomes. Furthermore, the study discusses how the new Jamestown fishing harbour complex project has displaced small-scale fishing actors and become a site of contestation between a coastal fishing community and local government authorities. In conclusion, as coastal fishing actors lose their only source of livelihood, resistance may escalate into different forms of maritime conflicts in the blue economy. The study recommends addressing the marginalisation and exclusion of traditional coastal fishing livelihoods to ensure a more equitable blue economy.
Clinical effectiveness of alkasite versus nanofilled resin composite in the restoration of occlusal carious lesions in permanent molar teeth of children: a randomized clinical trial
Authors: Sharma H. , Suprabha B. S. , Shenoy R. , Rao A. , Kotian H.
Published: March 2023

Purpose

To evaluate and compare the clinical effectiveness of alkasite with nanofilled resin composite restorations for occlusal caries lesions in permanent molar teeth of children, at one-year follow-up.

Methods

In this randomized controlled clinical trial with parallel design, 38 children aged 7–13 years with occlusal caries lesions on 59 first permanent molars were randomly allocated into two groups, Group 1: Filtek™ Z350XT (nanocomposite) and Group 2: Cention N® (alkasite resin composite). The restorations were evaluated at one year using the United States Public Health Service (USPHS) criteria. Data were analyzed using Chi-square or Fisher’s exact test.

Results

All restorations had either Alpha or Bravo scores at one-year follow-up. In Group 1, all restorations scored Alpha, while one restoration each (3.6%) in Group 2 scored Bravo for fracture and marginal adaptation. All restorations in both groups scored Alpha for retention, secondary caries, and post-operative sensitivity. For anatomic form, all restorations in Group 1 scored Alpha, while three (10.7%) restorations in Group 2 had Bravo scores. For marginal discolouration, three restorations in both groups scored Bravo (11.5% and 10.7%, respectively). For surface roughness, one restoration (3.8%) in Group 1 and three restorations in Group 2 (10.7%) scored Bravo. The comparative results between the two groups for all the variables in the USPHS criteria were not statistically significantly different.

Conclusions

The performances of the nanofilled composite and alkasite were clinically acceptable and comparable. Alkasite can be an alternative material for the restoration of occlusal caries lesions in permanent molars of children.

Clinical trial registration

The clinical trial was registered at Clinical Trials Registry—India (CTRI Reg no: CTRI/2020/12/029830 Dated: 15/12/2020).
Research on the Medical Knowledge Deduction Based on the Semantic Relevance of Electronic Medical Record
Authors: Qiao Zhi , Zhang Fuhui , Lu He , Xu Yan , Zhang Guibin
Published: March 2023

This paper studies the extraction of information from unstructured text data of medical literature and electronic medical records in the field of medicine, and proposes a TCM-KR method of knowledge reasoning based on electronic medical records to enhance association rules, and carries out a study on association characteristics in the field of the electronic medical record. This method abstracts the word bag representation mode of text semantics from the unstructured data representation and integrates the correlation information of the knowledge graph of the medicine domain. The method based on a graph convolutional network was used to predict the unknown associations' relations between viscera, channel tropism, and channel distribution. The experimental results show that the TCM-KR method can efficiently infer a large amount of high-quality triple knowledge from the unstructured text data of medicine, and predict the correlation characteristics of Syndromes-Viscera, Chinese medicinal-Channel tropism, Acupoints-Channel distribution in treating lumbar intervertebral disc prolapse and provide a dedicated machine learning model and guidance for clinical diagnosis and treatment.
Irish Migrants in New Zealand, 1840-1937
Authors: McCarthy Angela
Published: March 2023

An innovative and original contribution to the history of European migration between the mid-nineteenth century and the interwar years.
Towards a common terminology in radioglaciology
Authors: Schlegel Rebecca , Kulessa Bernd , Murray Tavi , Eisen Olaf
Published: March 2023

Over the past 70 years, many different components of the cryosphere have been imaged with a variety of radar systems using increasingly sophisticated processing techniques. These systems use various pulse lengths, signal frequencies and, in some cases, modulated signals. The increasing diversity of radar systems has created the potential for confusion due to the use of non-consistent terminology. Here we provide an overview of state-of-the-science radar technologies and suggest a simplified and unified terminology for use by the cryosphere community. We recommend a terminology that is target independent but specifies the characteristics of the signal. Following this recommendation, commercial impulse systems that penetrate the subsurface should be referred to as ground-penetrating radar (GPR), and pulse radars as radio-echo sounding (RES). Continuous-wave (CW) radar systems should be referred to as ground-penetrating CW radars. We further suggest any additional characterisation of the system be expressed using descriptors that specify the platform it is mounted on (e.g. airborne) or the frequency range (e.g. HF (high frequency)) or modulation (e.g. FM (frequency modulated)).
The Management of the Bank of Senegal and the Formation of a Colonial Economy, 1840s–1901
Authors: Masaki Toyomu
Published: March 2023

In 1854, the Bank of Senegal was established using part of the compensation paid to former slave owners. The bank issued banknotes and provided modern financial services. Masaki analyzes the bank’s management and interrogates the widely accepted argument that merchants from Bordeaux controlled the bank to marginalize African merchants, concluding that the bank largely provided equitable service to this colony. Additionally, Masaki shows that the bank was a site of political struggles for the métis elites and suggests that the complexities of Senegalese society at the time made it difficult to assess the full scope of the bank’s operations.
Special Economic Zones in an Era of Multilateralism Decadence and Struggles for Post-Pandemic Economic Recovery: Perspectives from the Global South
Authors: Simo Regis Y.
Published: March 2023

Recent years have seen a proliferation of Special Economic Zones (SEZs) in developed and developing countries. Developed in Europe in its modern shape, most SEZs are located outside the continent today, notably in the developing world, where SEZs form part of these countries’ export-oriented growth policy tools and overall economic development. At a period of growing unilateralism and the return of the State as an economic actor, this contribution seeks to tackle the rise of SEZ laws in the global south, with a particular focus on Africa. It will scrutinize the reasons for their establishment, the measures chosen to promote them, and the international ramifications in these respective regions and broadly on the global plane, notably at the WTO. With the entry into force of the African Continental Free Trade Area (AfCFTA) Agreement, African countries face challenges of multi-layered SEZ governance, which this contribution intends to address. These challenges also extend to the cross-regional trade agreements these countries conclude, individually and as a bloc. Since SEZs are often assimilated with a category of subsidies and are discriminatory trade measures, this contribution, in essence, investigates the extent to which current trade rules at multilateral and regional levels address these controversial aspects of SEZs.
Disciplining Subsidies Through Free Trade Agreements (FTAs): Emerging Developments in Japan’s FTAs and Their Implications
Authors: Iino Aya
Published: March 2023

The international economic order is undergoing significant change. Most recently, key countries have been seeking to increase their level of economic security, including through increased industrial subsidies. Regulating subsidies is controversial, but undisciplined subsidy payments could be harmful for the healthy functioning of markets and balanced development among nations. In this regard, the GATT-WTO has regulated subsidies, but it has not been fully functional in recent years, and reform efforts do not appear to be bearing fruit soon. Therefore, in parallel with WTO reform efforts, reliance on other approaches, such as discipline through free trade agreements (FTAs), should be considered. Disciplining subsidies through FTAs is inherently difficult, given the cross-border nature of subsidies on the one hand and the geographical limitations of the FTA’s scope of application on the other. In recent years, however, such disciplines in FTAs have begun to appear, starting with EU FTAs. Thus, this article explores the possibilities and limitations of the discipline of subsidies through FTAs, using Japan’s FTAs as a case study, to approach the path to international control of subsidies. Accordingly, this article first reviews the range of related issues and developments, including characteristics of subsidies, the rationale for subsidy discipline in trade agreements, recent challenges to multilateral subsidy discipline, the current status of subsidy discipline through FTAs, and the background of subsidy discipline in EU FTAs. The article then identifies the WTO-plus elements that are distinct to subsidy disciplines in EU FTAs and discusses their implications. Through these, it highlights the perspectives needed when considering subsidy discipline through FTAs, examines Japan’s FTAs in light of these perspectives, and presents the findings and implications thereof. Considerations are given to Japan’s FTA/trade policy as a background for its subsidy discipline through FTAs, the current status and characteristics of subsidy disciplines in Japan’s FTAs, the Agreement Between the European Union and Japan for an Economic Partnership’s (JPN-EU) subsidy-related provisions as drastic change, the effects on the Asia-Pacific region, and future prospects.
The linear-time-invariance notion of the Koopman analysis. Part 2. Dynamic Koopman modes, physics interpretations and phenomenological analysis of the prism wake
Authors: Li Cruz Y. , Chen Zengshun , Tse Tim K.T. , Weerasuriya Asiri Umenga , Zhang Xuelin , Fu Yunfei , Lin Xisheng
Published: March 2023

This serial work presents a linear-time-invariance (LTI) notion to the Koopman analysis, finding consistent and physically meaningful Koopman modes and addressing a long-standing problem of fluid mechanics: deterministically relating the fluid excitations and corresponding structure reactions. Part 1 (Li et al., Phys. Fluids, vol. 34, no. 12, p. 125136) developed the Koopman-LTI architecture and applied it to a pedagogical prism wake. By a systematic analytical procedure, the Koopman-LTI generated sampling-independent linear models that captured all the recurring dynamics embedded in the input data, finding six corresponding, orthogonal, and in-synch fluid–structure mechanisms. This Part 2 analyses the six modal duplets to underpin their physical implications, providing a phenomenological analysis of the subcritical prism wake. Visualizing the newly proposed dynamic Koopman modes, results show that two mechanisms at St1 = 0.1242 and St5 = 0.0497 describe shear layer dynamics, the associated Bérnard–Kármán shedding and turbulence production, which together overwhelm the upstream and crosswind walls by instigating a reattachment-type of reaction. The on-wind walls’ dynamical similarity renders them a spectrally unified fluid–structure interface. Another four harmonic counterparts, namely the subharmonic at St7 = 0.0683, the second harmonic at St3 = 0.2422, and two ultra-harmonics at St7 = 0.1739 and St13 = 0.1935, govern the downstream wall. Finally, this work discovered the vortex breathing phenomenon, describing the constant energy exchange in the wake's circulation-entrainment-deposition processes. With the Koopman-LTI, one may pinpoint the exact excitations responsible for a specific structure reaction, benefiting future investigations into fluid–structure interactions and nonlinear, stochastic systems.
The repair shop of memory
Authors: McCarroll Christopher Jude , Kirby Alun
Published: March 2023

In the BBC show, The Repair Shop, members of the public bring their cherished but crumbling possessions into a workshop populated by expert craftspeople, who carry out restorations. These objects arrive as treasured possessions, which, despite their dilapidated state, still hold memories and meaning for their owners, albeit memories that may have faded as the object itself has aged. Something magical seems to take place after the objects are restored, however. The restored objects seem to reanimate and revive the memories that their owners have invested in them. How is it possible that this restoration can bring memories held by the objects back to life? What is special about The Repair Shop restoring objects to their former glory? We outline two ways in which objects can be evocative and embody emotion, memory, and meaning. We then outline the ways in which the restoration of these objects to something like their original form can improve scaffolded recall and bring memories back to life. For one class of evocative objects, the restoration enhances recall by reinstating details from the context in which the memories were encoded. For the second class of evocative objects, their restoration affords an imaginative connection to the past, which enables them to become powerful focal points of memory and shared narratives. In effect, The Repair Shop seems to work not only as a repair shop of objects but as a repair shop of memory too.
Transnational Activism against Genocide Denial: Protesting Peter Handke’s Nobel Prize in Literature
Authors: Paul Johanna
Published: March 2023

This article addresses the protest against the 2019 Nobel Prize in Literature to Peter Handke as an example of transnational memory activism. It analyzes from a transnational mobilization perspective how activists achieved a globally visible protest in Stockholm and what role memory played in the protest mobilization and framing. Genocide survivors and former refugees, human rights activists, journalists, and academics formed a transnational protest coalition. In this way, they drew international attention to their outrage at the honoring of an author who is criticized for denying the Bosnian genocide. The analysis shows that memories of the violent dissolution of Yugoslavia and genocide united the diverse protesters as a “memory community” and shaped their framing. The protesters warned of the potential repercussions of the Nobel Prize to Handke for the internationalization and normalization of genocide denial. They argued that locally, Serb nationalist politicians can find legitimation in it for divisive politics. Moreover, they put the prize in a larger context of globally rising right extremism and islamophobia that find inspiration in the very Serb nationalist ideology and its propagators of the 1990s conflict.
Origins of life: first came evolutionary dynamics
Authors: Kocher Charles , Dill Ken A.
Published: March 2023

When life arose from prebiotic molecules 3.5 billion years ago, what came first? Informational molecules (RNA, DNA), functional ones (proteins), or something else? We argue here for a different logic: rather than seeking amolecule type, we seek adynamical process.Biology required an ability to evolve before it could choose and optimise materials. We hypothesise that theevolution processwas rooted in thepeptide folding process.Modelling shows how short random peptides can collapse in water and catalyse the elongation of others, powering both increased folding stability and emergent autocatalysis through a disorder-to-order process.
Melchior Bauer's cherub wagon
Authors: Hart Clive , Hart Helen Linthorne
Published: March 2023

No eighteenth century designer of flying machines surpassed Melchior Bauer in imagination and aerodynamic insight. Born on 19th October 1733 at Lehnitzsch, a village near Altenburg, he was the son of a gardener, Hans Bauer'1'. Little is known of his life, but in 1763 he went to London, where he sought patronage from the recently crowned King George III for the construction of a man-powered aircraft. According to his own account, he got no further than the official scribe who refused to copy out the submission, saying that even if he were offered £500 he would never agree to send such folly to the Court. ‘If you could do all that you claim,’ said the scribe, ‘you would certainly be the foremost and greatest man on earth.’ [1 r](2).
Energy Conservation Designing systems for the least fuel penalty on the aircraft
Authors: Le Claire R.
Published: March 2023

The integration of a system—or a group of systems — into a modern fixed-wing aircraft can only be satisfactorily achieved if the fuel penalty incurred by the aircraft is minimised, i.e. if the amount of fuel needed to restore the initial aircraft performance is kept to a minimum.

Over the years, aircraft systems have had to meet more and more stringent requirements which reflect not only on the increasing performance of aircraft, but also on the greater demands made by systems on the aircraft, a somewhat extreme example being that of the Mach 2 + Rockwell International B-l bomber on which the cooling requirements for the avionic equipment were to exceed several hundred kilowatts.

As such trends are likely to continue in the foreseeable future, the current deteriorating situation regarding fuel supplies and the ever rising costs involved, stresses the need for ensuring that systems on the next generation aircraft are designed for the least penalty and most efficient use of the available fuel.
Back to basics
Authors: Morgan P. H.
Published: March 2023

The flight test engineer constantly strives to provide solutions to the problems of testing, developing and proving the progressively more complex and accurate navigation and attack systems of modern military aircraft. The biggest such challenge in Europe for some time was probably the flight trials programme on the swing-wing Tornado aircraft which has a digitally based, self contained, al-lweather NAV/ATTACK avionics system. This paper covers the philosophy and techniques adopted for the flight testing and subsequent analysis of major elements of this system.
The drag of slant-based bodies of revolution
Authors: Maull D. J.
Published: March 2023

The drag of slant-based three-dimensional bodies such as the upswept rear fuselage of some aircraft (see for instance McCluney and Marshall and Peake) and car shapes (Morel) can be high and it is generally recognised that this high drag is associated with powerful longitudinal vortices in the flow direction. Morel has shown that the formation of these vortices, and therefore the drag, is a function of the slant angle of the base. His experiments were conducted with the body at zero incidence only and it appears that the effect of body incidence on the drag is unrecorded, although Bearman mentions that it has a significant effect.
Studies on Thwaites’ method for wind tunnel contraction
Authors: Tulapurkara E. G.
Published: March 2023

Nearly 15 methods have been proposed to obtain the shape of an axisymmetric wind tunnel contraction, but only a few have been studied experimentally. Bibliographic details of these methods can be found in Refs. 1, 2 and 3. Of these, the method described by Thwaites has the advantage that the contour and the velocity distributions are given directly by simple series expression. This method also has the criticism that the solution is periodic and does not satisfy near uniform stream condition obtained at inlet and outlet. But such a criticism applies to all methods which assume the length of contraction to be finite (e.g. methods due to Batchelor and Shaw, Chmielewski. Further, an experimental investigation by Klein et al(3) showed that Thwaites’ method with first four terms in solution gave a better performance than the contour given by Batchelor and Shaw.
Applications of carbon fibre composites to military aircraft structures
Authors: Sharples T.
Published: March 2023

The purpose of this paper is to give a fairly detailed description of where carbon fibre composites are most likely to be used in the structures of future military aircraft together with an indication of the structural configurations.
The manufacture of composite rotor blades
Authors: Wilson R. J.
Published: March 2023

Criteria for the design of helicopter rotor blades has been long established but the introduction of composite materials opens up new means of achieving these.

As an introduction to the subject I would like to look briefly at the design considerations under the headings:

1.

Aerodynamics

2.

Dynamics

3.

Strength
A modular low-cost raster-scan colour visual system
Authors: Willis P. J.
Published: March 2023

The author and colleagues at the University of Sussex have been investigating technical problems related to the production of moving colour pictures representing real scenes in real-time. The object is to produce a visual system suitable for vehicle simulation. Flight simulation is generally the most difficult to achieve because of the need for freedom of movement and orientation in three-dimensional space coupled with a rapidly changing scene.

Such a system must therefore show smooth motion and reasonable realism. These factors imply a picture update rate of around 25 frames per second, the use of a wide range of colours and textures, a large terrain model, a picture generator capable of representing surfaces and a good mathematical aircraft performance model.
Simulation research: role of university, government and industry in the Netherlands
Authors: Gerlach O. H.
Published: March 2023

The relevance of this subject to the theme of today’s discussions lies in the fact that the universities play an important part in aerospace research and that significant research in the field of flight simulation can easily lead to the requirement for rather costly equipment which universities usually find difficult to obtain. This may well have been one of the major stumbling blocks preventing the universities from taking a more active part in flight simulation. The outsider may perhaps wonder why it seems to have been possible in the past to avoid some of these difficulties in the Netherlands.
Towards a new industrial revolution
Authors: Page Freierick W.
Published: March 2023

Before 1800 Dr. Johnson observed that ‘the age is running mad with innovation’ and ‘every Master Manufacturer hath a new Invention of his own and is daily improving on those of others’. By the middle of the 19th century this first industrial revolution had made Britain the world leader in the application of steam power, in railways and in the output of coal, iron, steel, cotton cloth, and other manufactured goods. Yet by 1886 the Commission of Enquiry into the Economic Depression stated ‘We are no longer alone. More active rivals with better equipment are springing up and leaving us behind’. Between the turn of the century and the First World War, some of those rivals—in particular the USA and Germany—had eliminated our earlier lead and had gone ahead in key industrial sectors.
Calculation of two-dimensional and three-dimensional regular shock intersections
Authors: Hunt B. L.
Published: March 2023

The intersection of two oblique shock waves of opposite families is a common occurrence in supersonic flows. It can result either in a regular intersection, where the downstream waves are weak shocks and a single slip line emanates from the intersection, or in a form of Mach reflection where a strong shock bridges the gap between two three-shock confluences each of which generates a slip line. The transition between regular and Mach reflection has been discussed for the symmetrical case by Henderson and Lozzi and by Horning et al. The conditions at a three-shock confluence point have been analysed for two-dimensional flow by Henderson and for three-dimensional flow by Hunt and Lamont and by Rudman.
The views of the regulatory authority
Authors: Colegate R.
Published: March 2023

The first point which must be made—and I may not be the only speaker today who will make it—is that there is nothing new in a low air fares policy, at least so far as the United Kingdom is concerned. During the 1950s British independent airlines pioneered low fare scheduled services to Africa—the ‘colonial coach’ services. Much of the expansion in air travel that occurred between the United Kingdom and Europe and on the North Atlantic in the 1960s was due to the availability of low fares on charter services. Control over the minimum prices of inclusive tour holidays in Europe was finally suspended by the United Kingdom in 1972. In the same year, Edward Heath, addressing the Annual General Meeting of IATA in London, bluntly warned the scheduled airlines of the world that if they did not cater for the mass travel market by offering low fares, Governments would make sure that somebody else did. In the same year Laker Airways was licensed to operate a Skytrain service to New York—a scheduled service geared specifically to a low fares policy.
Air transport users’ views
Authors: Hope Archibald
Published: March 2023

The first point which I wish to make, speaking on behalf of the Air Transport Users Committee, is that low fares are still an exception rather than the rule outside North America. There are some genuine low fares on the North Atlantic and many inclusive tour fares from this country, as other speakers have said, can be classified as genuinely low. Elsewhere in the world fares are still much too high, although we have been glad to see a slight reduction in fares to Scandinavia and to Australia.

While users very naturally are interested in low fares and do not wish to pay more than is absolutely necessary for their travel, they do have reservations regarding low fares which are achieved by very high seat factors rather than by genuine reduction in cost.
Aircraft longitudinal motion at high incidence
Authors: Babister A. W.
Published: March 2023

In the analysis of aircraft flight dynamics problems at high incidence, non-linear aerodynamic effects are of considerable importance. The aerodynamic phenomena are generally extremely complicated and the non-linearities may be difficult to predict quantitatively. In this note we confine our attention to longitudinal symmetric motion at constant speed and height. Our aim is (i) to enable the pilot to know when he is in a potentially dangerous manoeuvre (which could lead, for example, to a super-stall) and (ii) to determine simple control laws for an autopilot which would prevent such a super-stall occurring.
Design and development of the Agusta A 109 helicopter
Authors: Lovera Bruno
Published: March 2023

A new generation of helicopters was born at the beginning of the sixties, when, following a US requirement for a light observation helicopter (LOH), a new breed of military machines, like the Bell 206 (OH-4 A, OH-58 A), the Hiller 1100 (OH-5 A) and the Hughes 500 (OH-6 A) was developed.

All the aerodynamic and structural progress resulting from the previous experience of the helicopter industry was incorporated in their designs. The development of these helicopters, demonstrating good performance and comfort levels, light and relatively inexpensive was made possible, however, only because of the availability of a new, light turboshaft engine, featuring acceptable levels of fuel consumption and reliability.
Burattini's flying dragon
Authors: Hart Clive
Published: March 2023

Largely as a result of frequent written reports by Pierre Des Noyers, secretary to the Queen of Poland, mid-seventeenth century scientists took a great deal of interest in the aeronautical work of an Italian engineer, Tito Livio Burattini. Born in Agordo, north of Venice, on 8th March 1617, Burattini early became a travelling scholar. By 1637 he had reached Egypt, where he helped John Greaves with his famous work on the pyramids. Despite his youth, he appears greatly to have impressed Greaves, who referred to him, with slight inaccuracy, as ‘Titus Livius Burretinus, a Venetian, an ingenious young man'. In 1641 Burattini returned to Europe, spending a little time in Germany and travelling on to Poland, where he lived until 1645. In 1647, after a visit to his native Italy and a second period in Egypt, he settled permanently in Poland, where he attempted, soon after his arrival, to establish himself at the court of Wladislaw IV (30th May 1595-20th May 1648).
Impact of onboard processing on data-handling for space applications
Authors: Pellet M. , Rowles J. B.
Published: March 2023

If one sees a satellite as being a remote sensing platform or as a communication path between two terminals on the Earth, one can appreciate that the spacecraft and its complementary ground infrastructure are essentially electronic devices handling data for the benefit of a ground-based investigator or user. As such, there is a space data-handling system which comprises an onboard and a ground segment. Both segments cover the functions of data collection, data distribution, data processing and storage, data encoding and decoding, timing and synchronisation of events, and data transmission and reception currently forming the well known telemetry data link and the telecommand data link (TTC).
British civil airworthiness requirements for airships
Authors: Niedermayer E. J.
Published: March 2023

Prior to 1937, responsibility for civil aviation in the UK, including airworthiness and operation of airships, was vested in the Air Ministry, a Government department, and it was only in 1937 that it was devolved to an independent authority, the Air Registration Board, which is now the Airworthiness Division of the CAA.

The first involvement of the CAA with airships occurred early in the present decade when it was confronted firstly with an extremely unorthodox configuration of airship. The Skyship project (Fig. 1) was 720 ft in diameter, 48 million cu ft in volume, and 400 tons pay-load capacity.
Designing for long-life aircraft structures
Authors: Harpur N. F.
Published: March 2023

Many aircraft in service today have already achieved lives considerably greater than those originally anticipated by their designers. One thinks of aircraft like the Douglas DC-3, still going strong in many parts of the world after 40 years. Even aircraft like the Vickers Viscount, the world’s first successful turbo-prop air liner, are much ‘longer in the tooth’ than one might at first think; the oldest airframe still in regular service left its makers 27 years ago. Geriatric is the word which has been coined to describe such aircraft and, based on its dictionary definition of ‘care of the old’, the description is probably apt. However, this term is often wrongly thought of as synonymous with senile which, from its dictionary definition of ‘feebleness of old age’, is most inappropriate to such aircraft. It is interesting to examine first the longevity of current aircraft, secondly the application of the science of geriatrics to them and finally the means by which the expectation of life of new types of aircraft may be increased.
General aviation: its viability as a mode of transport in the UK
Authors: Caves Robert
Published: March 2023

There has recently been evidence of an upsurge of activity in general aviation in the United Kingdom, particularly in small scheduled operations which are frequently referred to as ‘third level’. Much of the non-scheduled activity has been generated by North Sea exploration and the tendency for stronger ties with the European Economic Community (EEC). The recent growth in third level operations owes some of its impetus to each of these reasons, but there have also been moves to operate domestic links on routes which are not well served by the ground transport infrastructure. These include the Newquay-Gatwick and Norwich-Birmingham-Swansea-Newquay routes, the helicopter service between Fort William and Glasgow, the formation of Air Wales and Air Westward and the intention of British Caledonian to set up its own network of third level feeders for its international services at Gatwick.
Concorde in service
Authors: Strang W. J. , McKinlay R. M.
Published: March 2023

In the two and a half years that Concorde has been in service with British Airways and Air France, the nine aircraft in service have carried 250 000 passengers, travelled 16 million miles and accumulated 15 310 flying hours. These numbers, though still small by airliner standards, are sufficient for effective comparison of service experience with predictions made and objectives set during the design process. This provides the central theme of our paper.

The Concorde project, always controversial, has been assessed many many times on technical, economic and environmental grounds. In fact it has inspired a literature of its own, comprising papers of all kinds–favourable and unfavourable, learned and hysterical. It has been the subject of predictions by the hundreds, ranging from the optimistic to the absolutely dire. This paper, written with the benefit of hindsight, is thereby distinguished from the bulk of this literature.
Computer-aided design: aerodynamics
Authors: Haines A. B.
Published: March 2023

In recent years, there have been rapid advances in the development of theoretical methods in aerodynamics, particularly for transonic flow calculations. Many papers have been written on this topic. It is however appropriate that there should now be a paper that concentrates not so much on the methods themselves but on the use of the methods for computer-aided design. One could say that the most striking development in the UK in the past two-three years has been that the methods are no longer merely within the preserve of the research establishments; they are being actively used by the aircraft industry in the design of actual aircraft projects. Any air of scepticism about their value has been dispelled. The designers are now appreciating through their own experience that with the aid of a powerful computer and indeed in some cases, a computer of only modest capacity, they can specify a shape for the first wind tunnel model of a new project with much more confidence that the test results will show that the shape is near what is required to achieve their design objectives. It is already being claimed that in this way, the time-scale of the design cycle is being shortened considerably. Also, the computer and the theoretical methods are being used increasingly in the interpretation of the test data. The forecasting of the full-scale characteristics on the basis of the model test data is developing into more of a science and less of an art based on past experience.
Study of installed environment of various equipments in military aircraft
Authors: Jones G.
Published: March 2023

When British Aerospace, Brough, were first tasked with carrying out a study of mechanical systems and component reliability it was anticipated that the installed environment would be a significant parameter in the investigation. Consequently it was decided to carry out a separate study of the environment of equipment on a number of aircraft to assess how this had influenced the design and subsequent reliability of the components and to see if the initial assumptions had been valid. This study was to make use of measured data from routine development flying as well as tropical and cold weather trials. In addition the reliability of appropriate equipment was reviewed to determine the incidence of problems arising from environmental factors.

The installed environment can be broken down badly into two separate factors. Firstly, those which are external to the components in question, e.g. altitude, ambient temperature, humidity, vibration levels, solar radiation and contaminants such as salt, sand and dust. Secondly, there are those factors which are internal to the component in question or are influenced by the installation of the component in a larger system. These factors include internal pressures, temperatures and contaminants, the effect of the system flows and interaction with other components.
Some observations on the local instability of orthotropic structural sections
Authors: Lee D. J.
Published: March 2023

The local buckling behaviour of structural sections composed of isotropic flat plate elements is well documented. The results are most conveniently presented in the form of curves for the minimum buckling coefficient, Kmin, against the flange/web ratio λ2. A series of such curves for a range of structural sections composed of orthotropic plates subjected to uniform end loads and simply supported end constraints has been presented by the author. For isotropic sections of practical proportions, it is generally assumed that the buckling coefficients for columns with simply supported and built-in end conditions approach the common value Kmin, and that the half wavelength of the buckle mode in the axial direction is of the same order as the cross-sectional dimensions of the column. For structures composed of highly orthotropic materials such as carbon fibre reinforced plastic (CFRP), the half wavelength is much greater than that of the isotropic counterpart. In consequence, it is only for much longer sections that the common value of Kmin, can be assumed for the buckling coefficient of built-in orthotropic sections without excessive error.
Relationships between turbulent intensities in turbulent pipe and channel flows
Authors: Mosa Kaisar , Alshamani Mati
Published: March 2023

Axial, normal (radial) and tangential turbulence intensity measurements have been carried out in the past in pipe and two-dimensional channel flows, e.g. Refs. 1-9. A similarity in the distribution of these turbulence intensities is observed. They are all minimum at the centreline, increasing steadily as the wall is approached, until they reach some maximum values close to the wall, then they start to decrease as the wall is approached further. Furthermore, the three components of turbulence intensity have been observed to vary in a similar way with the Reynolds number.

On the other hand, the Prandtl mixing length theory assumes that the turbulent fluctuations are proportional to the product of a local mixing length and a velocity gradient. This implies that the turbulence fluctuations are directly proportional to each other. It is, therefore, found worthwhile examining the possibility of a relationship between the turbulence intensities. Smooth pipe and channel flows are chosen for this purpose.
Progress in the use of automatic flight controls in safety critical applications
Authors: Howard R. W.
Published: March 2023

High authority automatic flight control systems are now in wide use in both transport and combat aircraft. These have required the development of failure survival system architectures, and techniques in safety assessment to ensure that the risk of fatal accidents attributable to the automatic control aspect is acceptably remote.

Most of the current systems are analogue in nature, and employ sufficient redundancy to survive at least one failure during operation. Future systems will employ quadruplex or triplex-monitored architectures, capable of surviving at least two failures, and will be mainly digital in concept. The design and safety assessment techniques developed for analogue systems have been adequate for current systems, but the new digital technology and more extensive use of systems in safety critical applications will demand further development of the various aspects involved.

A major contribution to the design and safety assessment of safety critical systems was made during the past two decades in the programmes for the development of automatic landing for civil aircraft, culminating in the system in the Anglo-French Concorde.
Impartial Administration and Peaceful Agrarian Reform: The Foundations for Democracy in Scandinavia
Authors: ANDERSEN DAVID
Published: March 2023

Why was the route to democracy in Scandinavia extraordinarily stable? This paper answers this question by studying Scandinavia’s eighteenth- and early nineteenth-century peaceful agrarian reforms, which contributed to auspicious state–society relations that made democracy progress relatively smoothly. Based on comparisons with contemporary France and Prussia and process-tracing evidence, the paper shows that Scandinavia achieved relatively extensive and peaceful agrarian reforms because of relatively high levels of meritocratic recruitment to the central administration and state control over local administration, which ensured impartial policymaking and implementation. These findings challenge prevailing theories of democratization, demonstrating that the Scandinavian countries represent an alternative, amicable path to democracy led by civil servants who attempt to transform their country socioeconomically. Thus, strong state-cum-weak society countries likely have better odds of achieving stable democracy than weak state-cum-weak society countries. However, building bureaucratic state administrations alongside autonomous political societies is probably a safer road to democracy.
MIN-PHASE-ISOMETRIES IN STRICTLY CONVEX NORMED SPACES
Authors: TAN DONGNI , ZHANG FAN
Published: March 2023

Suppose that X and Y are two real normed spaces. A map
$f:X\rightarrow Y$
is called a min-phase-isometry if it satisfies
$$ \begin{align*} \min\{\|f(x)+f(y)\|,\|f(x)-f(y)\|\}=\min\{\|x+y\|,\|x-y\|\} \quad (x,y\in X). \end{align*} $$

We present properties of min-phase-isometries in the case that Y is strictly convex and show that if a min-phase-isometry f (not necessarily surjective) fixes the origin, then it is phase-equivalent to a linear isometry, that is,
$f(x)=\varepsilon (x)g(x)$
for
$x\in X$
, where
$g:X\rightarrow Y$
is a linear isometry and
$\varepsilon $
is a map from X to
$\{-1,1\}$
.
Comparative transcriptomic analysis of mammary gland tissues reveals the critical role of GPR110 in palmitic acid-stimulated milk protein and fat synthesis
Authors: Zhang Minghui , Ma Zonghua , Qi Hao , Cui Xu , Li Rui , Gao Xuejun
Published: March 2023

The G protein-coupled receptors (GPCR) sensing nutritional signals (amino acids, fatty acids, glucose, etc.) are not fully understood. In this research, we used transcriptome sequencing to analyse differentially expressed genes (DEG) in mouse mammary gland tissues at puberty, lactation and involution stages, in which eight GPCR were selected out and verified by qRT-PCR assay. It was further identified the role of GPR110-mediating nutrients including palmitic acid (PA) and methionine (Met) to improve milk synthesis using mouse mammary epithelial cell line HC11. PA but not Met affected GPR110 expression in a dose-dependent manner. GPR110 knockdown decreased milk protein and fat synthesis and cell proliferation and blocked the stimulation of PA on mechanistic target of rapamycin (mTOR) phosphorylation and sterol-regulatory element binding protein 1c (SREBP-1c) expression. In summary, these experimental results disclose DEG related to lactation and reveal that GPR110 mediates PA to activate the mTOR and SREBP-1c pathways to promote milk protein and fat synthesis.
Vertigo symptom scores and videonystagmographic examinations in recovered coronavirus disease 2019 patients
Authors: Cekic E , Uşaklıoğlu S
Published: March 2023

Objective

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) may be among the viral agents that affect the audio-vestibular system. This study aimed to investigate vestibular symptoms and videonystagmographic examinations in recovered coronavirus disease 2019 (Covid-19) patients compared with the control group.

Method

The patients were evaluated with Vertigo Symptom Scale questionnaire and audiometric, tympanometric, stapedial reflex and videonystagmographic examinations.

Results

A total of 92 of the patients in the coronavirus disease 2019 patients group and 25 of the volunteers in the control group were included in the study. The mean Vertigo Symptom Scale score was found to be significantly higher (p <0.001) in the coronavirus disease 2019 group. Furthermore, one of the hospitalised patients was diagnosed with vestibular neuritis.

Conclusion

The vestibular system may also be affected in some coronavirus disease 2019 patients. Although this may be seen as dizziness in some patients, in rare cases it can cause severe issues, such as vestibular neuritis.