bluuebunny/crossref_metadata_2025 huggingface dataset:
Stable climate corridors promote gene flow in the Cape sand snake species complex (Psammophiidae)
Authors: Taft Jody M. , Maritz Bryan , Tolley Krystal A.
Published: October 2021

Climate shifts during the Quaternary Period have driven changes in regional range dynamics for many species, influencing population structure of species and in some cases promoting speciation. Within southern Africa, the psammophine snakes Psammophis trinasalis and P. namibensis were historically considered subspecies of P. leightoni but were elevated to species rank based on ecological differences. Preliminary phylogenetic analyses suggested intraspecific, not interspecific genetic variation between these taxa, but this finding was based on very limited data and could not be confirmed. To assess the level of genetic differentiation within the P. leightoni species complex, we explored the evolutionary history of these snakes by combining phylogenetic analyses, species distribution modelling and an examination of morphology. We generated a comprehensive, multi‐gene phylogeny for Psammophis that included wider geographic sampling of the three species in the complex. Using this phylogeny, Bayesian and distance‐based species delimitation analyses showed intraspecific, not interspecific divergences between taxa in the complex, suggesting that they collectively represent a single taxon. Furthermore, non‐metric multidimensional scaling analysis of scalation characters showed no differences between the species. Moreover, palaeo‐modelling at three time periods since the last interglacial period suggest that there have been varying levels of connectivity between these taxa, which has likely facilitated gene flow between them. Given the evidence, we propose that the P. leightoni complex represents a single species and therefore formally synonymise the three species.
Surface-Mounted Distributed Fiber Optic Sensor Measurements, and Concrete Damaged Plasticity Modeling for Damage Analysis of Reinforced Concrete Beams
Authors: Jayawickrema U. M. N. , Kumar A. S. , Herath H. M. C. M. , Hettiarachchi N. K. , Sooriyaarachchi H. P. , Epaarachchi J. A.
Published: October 2021

Structural health monitoring (SHM) has become an integral part of essential and costly to replace infrastructures such as bridges and buildings which degrade during their lifetime. Understanding the structural behaviour of these infrastructures is critical for assuring their structural integrity and safe operating conditions. In this study, the structural performance of a reinforced concrete beam was examined under flexural loading. Distributed optical fibre sensor (DOFS) was attached to the beam’s bottom surface, and Optical Backscattered Reflectometry (OBR) technology was used to measure the surface strain. A three-point bending test was performed, and the sensor responses were acquired. Unusual high strain peaks were observed at the bottom surface of the beam due to the formation of hairline cracks. Subsequently, the Concrete Damaged Plasticity (CDP) based Finite Element Analysis (FEA) was performed to simulate the plastic behaviour of concrete beam using ABAQUS 2019 commercial software. The FEA results have strong agreement with the strain pattern observed from the DOFS. Therefore, DOFS and CDP technique based FEA can be successfully used to investigate the plastic damage pattern inside the concrete beam and distributed sensing demonstrates a greater capacity for long-term monitoring of the structural health of concrete structures.
A Smart Controllable SMA-Based Tourniquet
Authors: Golgouneh Alireza , Li Jiaqi , Abel Julianna , Dunne Lucy E.
Published: October 2021

Textile-based compression devices are widely used in fields such as healthcare, astronautics, cosmetics, defense, and more. While traditional compression garments are only able to apply passive pressure on the body, there have been some efforts to integrate smart materials such as shape memory alloys (SMAs) to make compression garments active and controllable. However, despite the advances in this field, accurate control of applied pressure on the body due remains a challenge due to vast population-scale anthropometric variability and intra-subjects variability in tissue softness, even if the actuators themselves are fully characterized. In this study, we begin to address these challenges by developing a novel size-adjustable SMA-based smart tourniquet capable of producing a controllable pressure for circumferential applications. The developed prototype was tested on an inflatable pressure cuff wrapped around a rigid cylinder. The thermal activation of SMA coils was achieved through Joule heating, and a microcontroller and a programmable power supply are used to provide the input signal. To control the compression force, a closed-loop PID controller was implemented, and the performance of the system was evaluated in 5 different testing conditions for variable and cyclic compression levels. The experiments showed that the controlled system could follow the desired control pressure reference with a steady-state of 1 mmHg. The compression tourniquet is able to produce more than 33 mmHg with an average actuation rate of 0.19 mmHg/s. This is the first demonstration of accurate closed-loop control of an SMA-incorporated compression technology to the best of our knowledge. This paper enables new, dynamic systems with controllable activation and low-effort donning and doffing, with applications ranging from healthcare solutions to advanced spacesuit design.
Integration of SMA Wires Into the Additive Manufacturing Process Using PBF-LB/M and Long-Term Tests of the Specimens to Validate the Functional Properties
Authors: Schmelter Tobias , Theren Benedict , Thiele Magnus , Schuleit Marvin , Esen Cemal , Kuhlenkötter Bernd
Published: October 2021

The integration of shape memory (SM) wires in additive manufacturing (AM) processes and components, either as actuators or sensors, holds enormous potential for future developments. For example, a sensor or an actuator function could be integrated into a component already during the manufacturing process. This integration can eliminate downstream assembly steps and improve the flexibility of the component design. In addition to (complex) components, the AM process can also be used to attach connecting elements to the wire, ensuring an improved connection of the wire to other components like an actuator housing.

The integration of SM wires into an AM process will be further investigated in the following and feasibility validated by initial trials. Powder bed fusion – laser beam/metal (PBF-LB/M) is used as an AM process; thereby blocks are welded to the wire in the context of this work as proof of concept. Long-term and tensile tests are carried out to evaluate the functional and mechanical properties of the manufactured compounds. Moreover, images of a scanning electron microscope (SEM) in combination with energy dispersive X-ray spectroscopy (EDX) provide further information about the generated compound.
Indirect Impedance-Based NDE Through Instrumented Fixtures; Effects of Fixture Material on Defect-Detection Capabilities
Authors: Oyekola Peter O. , Mehedi Al-Barkat , Ivey Morgan , Albakri Mohammad I.
Published: October 2021

Electromechanical impedance allows for a quick assessment of the mechanical integrity of the part under test by providing insights into its dynamic response. In previous studies, it has been shown that electromechanical impedance signatures obtained via directly bonded piezoelectric transducers can successfully be used for non-destructive evaluation of manufactured parts. Indirect electromechanical impedance measurements, through an instrumented fixture or testbed, has also been introduced as a promising solution for quick evaluation of manufactured parts. While such indirect impedance measurements alleviate the need for individual parts to be instrumented, they increase the complexity of the measurement system. Factors such as fixture design, part-fixture interface, and clamping force are found to impact measurement sensitivity to manufacturing defects and anomalies.

In this paper, the effects of instrumented fixture material on indirect electromechanical impedance measurements are investigated. Three geometrically-identical fixtures are considered in this study. Two are commercially available clamps made of aluminum and steel, while the third is an additively manufactured replica made of PLA through a fused filament fabrication process. The fixtures are instrumented with monolithic piezoelectric transducers for electromechanical impedance measurement. Strain gauges are used to measure the clamping force exerted by the fixture on the part under test. Test specimens are made of machined steel blocks including defect-free (control) parts along with others featuring manufacturing defects. The impact of fixture’s material properties, as compared to the part under test, on the defect-detection capabilities of indirect impedance-based NDE is evaluated.
The Transient Response of Piezoresistive CNF-Modified Epoxy Rods to One-Dimensional Wave Packet Excitation
Authors: Hernandez J. A. , Zhu H. , Semperlotti F. , Tallman T. N.
Published: October 2021

Introducing conductive nanofillers into polymeric, cementitious, and ceramic composites can impart multifunctional properties such as self-sensing capabilities via the piezoresistive effect. Much work has been done to utilize this multifunctionality for conductivity-based structural health monitoring (SHM) and condition monitoring. To date, the majority of such investigations concern static and quasi-static loading conditions. Much less work has been done with regard to general dynamic loading conditions such as transient wave propagation. This is an important gap in state of the art for two reasons: First, the self-sensing nature of these materials potentially allows for full-field (i.e. sub-surface) dynamics monitoring which cannot be achieved via traditional surface-mounted dynamic sensors. And second, conductivity-based and vibratory-based SHM are both independently well researched areas. Combined into a single, piezoresistive elastodynamic formulation, however, they may give rise to unprecedented new diagnostic capabilities. Therefore, the initial results presented in this manuscript seek to address this gap in the state of the art by experimentally exploring the role of dynamic excitation on transient piezoresistive behavior in nanocomposite structures. Specifically, an electromagnetic shaker is used to inject highly-controlled planar strain wave packets into a slender prismatic carbon nanofiber (CNF)-modified epoxy rod. Resistance measurements are then taken as the wave packets travel along the length of the rod. It was found that resistance changes taken from the rod are able to accurately reconstruct the injected strain wave and can be used to discern dynamic properties of CNF-modified epoxy. An external laser vibrometry (LV) system was used as extrinsic validation. Results from this preliminary investigation may lay the foundation for a new exciting field of fully coupled piezoresistive elastodynamics.
Phenomenological Assessment of Post Constrained Recovery Residual Stress of Shape Memory Alloys
Authors: Haider Muhammad Istiaque , Salowitz Nathan
Published: October 2021

Shape memory alloys (SMAs) are frequently used in a broad spectrum of commercially valuable and innovative applications due to its high specific energy density as an actuator and simple thermal actuation. This paper presents a study seeking to understand a recently discovered property of Nickel Titanium (NiTi) SMAs where they can repeatedly produce stable residual stresses after undergoing constrained recovery and returning to a low temperature, martensitic, state. The underlying mechanisms of this post constrained recovery residual stress (PCRRS) are still under investigation.

Experiments on multiple formulations of NiTi based SMAs (including a ternary material) confirmed the PCRRS generation in every SMA tested and following the exposures to further application of small cyclic strain (both tensile and compressive) from PCRRS states revealed a cyclic softening like phenomena where the magnitude of residual stresses over every small strain exposure were incrementally reduced, but the repetition of the constrained recovery process reproduced the initial residual stress. This paper presents the results of new experiments that help explain the nature of the PCRRS phenomena, discussion of the cyclic softening phenomena with small strain applications and a conceptual study to understand the underlying mechanism of PCRRS based modulus comparison in different loading states during PCRRS generation.

The capability to produce PCRRS and its repeating regeneration provides a new way for the material to be used as an actuator that may be beneficial to applications like self-healing material and could support new applications like using a dispersion of NiTi particles to inhibit fatigue cracking in material structures. Novel actuation mechanism can be developed and designed through PCRRS based on the potential energy stored in the structures to use in different applications and smart material design.
Work Capacity of Self-Folding Polymer Origami
Authors: Long Ryan , Singla Deepika , Parmar Kanak , Indaco Manuel , Taylor Will , Adkins Nathan , Guzzetti Davide , Mailen Russell W.
Published: October 2021

Self-folding origami utilizes shape memory polymers (SMPs) to enable deployable space structures, such as those intended for large-scale, low-frequency radio interferometry. The size of structure that may be deployed is limited by the capacity of the smart material to do work. Previous studies focused on activation mechanisms and the kinematics of self-folding polymers, but have largely neglected an evaluation of the energy stored in the folding hinge. This paper seeks to characterize the work done by self-folding origami hinges made of pre-strained polystyrene (PSPS) as it deforms due to the shape-memory effect. SMP samples are patterned with black ink hinges and exposed to an infrared (IR) light. The ink absorbs thermal energy from the light, which leads to local heating and shrinking in the hinge region. Activation of the self-folding response, e.g. shrinking, occurs when the material reaches a temperature higher than its glass transition temperature, and a gradient in shrinking causes the sample to fold. The self-folding process is sensitive to physical constraints and changes in energy input into the sample. Thus, we will evaluate the energy stored in the self-folding hinge by measuring the work done under varying thermal stimuli in an array of tests that include universal material shrinkage and single-hinge folds. We evaluate hinge torque based on a dynamic analysis of the motion of the self-folding sheet. Quantification of the capacity of self-folding origami hinges to do work enables the design of deployable space structures by not only considering the activation mechanism and self-folding kinematics, but also accounts for the size of structure that may be deployed.
Resilience and Performance of Deployable Space Structures Based on a Shape Memory Polymer Bus
Authors: Singla Deepika , Long Ryan , Parmar Kanak , Indaco Manuel , Taylor Will , Adkins Nathan , Guzzetti Davide , Mailen Russell W.
Published: October 2021

We seek to advance the topic of large-scale space structures for low-frequency radio interferometry enabled by self-folding shape memory polymers (SMPs). Large-scale space structures, greater than 1 km in diameter, are necessary to unlock the secrets of the cosmological dark ages. Two important considerations in developing such large structures are their ability to deploy to the desired configuration in space and their resilience to harsh space environments, which include UV radiation, atomic oxygen, and thermal cycling under vacuum. These environments lead to long-term degradation and erosion of even the most resilient materials. Degradation of SMPs in space applications has potential to affect both material properties and shape-memory performance. Although a plethora of materials have been evaluated in space conditions, the coupled effects of simultaneous space environments on the properties and shape memory performance of polymers has not been evaluated sufficiently. In this study, we evaluate the effects of relevant space environments on the thermomechanical properties of candidate SMPs using laboratory-based experiments. Representative SMP samples are subjected to UV-Oxygen for varying durations. The effects of these environments on material properties for various amounts of exposure are evaluated using differential scanning calorimetry and dynamic mechanical analysis. Knowledge gained from this study includes how the shape recovery required for in-space deployment is affected by space environments and the resilience of these structures to long-term space exposure. Through improved understanding of the effects of space environments on SMP properties and performance, we can advance the field of low-cost, lightweight, self-deploying space structures.
Fully 3D Printed Soft Actuator With Embedded Sensing
Authors: Gonzalez Rodriguez David , Garcia Jose , Newell Brittany
Published: October 2021

Soft actuators have demonstrated great potential for utilization in many industrial applications due to their ability to be produced in unusual shapes, their capacity to conform within a containing envelope and their large power to displacement ratios. A great majority of these flexible structures are produced by casting processes, since they are generally composed of silicone materials due to their high elasticity and flexibility. Innovative 3-D printing techniques and flexible materials have been explored and utilized to produce soft actuators to overcome this limitation in production. This paper presents a 3-D printed soft actuator with embedded sensing capabilities and the ability to produce a signal based on its actuation position. Computational simulations were done to evaluate the performance of the actuator with embedded sensing to determine the resistance change in the embedded conductive element based on the deformation of the soft actuator. This work demonstrates control to actuate the soft actuator while sensing its deformation using a resistance-based sensor. The entire structure was produced using fused deposition modeling (FDM) techniques, in one continuous process without support material.
Resource relocations in relation to dispersal in Tetranychus ludeni Zacher
Authors: Zhou Peng , He XiongZhao , Chen Chen , Wang Qiao
Published: October 2021

Life history strategies of a species may affect its invasion success. Here, we used a haplodiploid pest, Tetranychus ludeni Zacher (Acari: Tetranychidae), which is native to Europe but now cosmopolitan, to investigate its life history strategies in relation to its dispersal tendency and distance. We tested whether and how dispersal influenced survival, lifetime fecundity, age-specific reproduction, and life table parameters of mated females. We show that mated females did not trade off their survival and lifetime reproductive output with dispersal but adjusted their resource allocations during different reproductive stages depending on whether and how far they dispersed. Long-distance dispersers invested more in dispersal in their early life while resident mites and short-distance dispersers invested more in reproduction during their early life. These resource allocation strategies may allow long-distance dispersers to explore the novel environment more effectively without compromising lifetime reproductive fitness, contributing to the invasion success of T. ludeni.
Synchronization of nonsolitonic Kerr combs
Authors: Kim Bok Young , Jang Jae K. , Okawachi Yoshitomo , Ji Xingchen , Lipson Michal , Gaeta Alexander L.
Published: October 2021

The universality of Kerr comb synchronization is demonstrated, extending its scope beyond the soliton regime.
Permanent magnet array–driven navigation of wireless millirobots inside soft tissues
Authors: Son Donghoon , Ugurlu Musab Cagri , Sitti Metin
Published: October 2021

A wireless magnetic millirobot navigates inside an ex vivo porcine brain propelled by a permanent magnetic array–based force trap.
The antiactivator FleN uses an allosteric mechanism to regulate σ
54
-dependent expression of flagellar genes in
Pseudomonas aeruginosa
Authors: Chanchal  , Banerjee Priyajit , Raghav Shikha , Goswami Hemant N. , Jain Deepti
Published: October 2021

FleN uses allostery and structural remodeling to fine-tune transcription activation by FleQ for monotrichous phenotype.
Shadowy first image of black hole revealed
Authors: Clery Daniel
Published: October 2021

Sharper pictures from the Event Horizon Telescope could test theory of gravity.
#MeToo controversy erupts at archaeology meeting
Authors: Wade Lizzie
Published: October 2021

Accusers saw alleged harasser at society's conference, butits new harassment policy did not cover the situation.
A bipedal walking robot that can fly, slackline, and skateboard
Authors: Kim Kyunam , Spieler Patrick , Lupu Elena-Sorina , Ramezani Alireza , Chung Soon-Jo
Published: October 2021

Synchronized control of propellers and legs enables a bipedal robot to fly, slackline, and skateboard.
Differential impact of physical distancing strategies on social contacts relevant for the spread of SARS-CoV-2: evidence from a cross-national online survey, March–April 2020
Authors: Del Fava Emanuele , Cimentada Jorge , Perrotta Daniela , Grow André , Rampazzo Francesco , Gil-Clavel Sofia , Zagheni Emilio
Published: October 2021

Objectives

We investigate changes in social contact patterns following the gradual introduction of non-pharmaceutical interventions and their implications for infection transmission in the early phase of the pandemic.

Design, setting and participants

We conducted an online survey based on targeted Facebook advertising campaigns across eight countries (Belgium, France, Germany, Italy, the Netherlands, Spain, UK and USA), achieving a sample of 51 233 questionnaires in the period 13 March–12 April 2020. Poststratification weights based on census information were produced to correct for selection bias.

Outcome measures

Participants provided data on social contact numbers, adoption of protective behaviours and perceived level of threat. These data were combined to derive a weekly index of infection transmission, the net reproduction numberRt.

Results

Evidence from the USA and UK showed that the number of daily contacts mainly decreased after governments issued the first physical distancing guidelines. In mid-April, daily social contact numbers had decreased between 61% in Germany and 87% in Italy with respect to pre-COVID-19 levels, mostly due to a contraction in contacts outside the home. Such reductions, which were uniform across age groups, were compatible with anRtequal or smaller than one in all countries, except Germany. This indicates lower levels of infection transmission, especially in a period of gradual increase in the adoption rate of the face mask outside the home.

Conclusions

We provided a comparable set of statistics on social contact patterns during the COVID-19 pandemic for eight high-income countries, disaggregated by week and other demographic factors, which could be leveraged by the scientific community for developing more realistic epidemic models of COVID-19.
Fastnet 1979
Authors: Millar C. W.
Published: October 2021

On August 14. 1979, there was a major disaster at sea due to unusually ferocious weather. The largest recorded search and rescue operation was mounted with aircraft from many Royal Naval and Royal Air Force airfields taking part. The assistance given by the Dutch guard ship was augmented by ships of the Royal Navy and mercantile marine. The helicopter base nearest to the scene of the incident was HMS Seahawk, so all survivors were processed through Culdrose sick bay. The first yachtsman to be received at Culdrose was a Frenchman at 0930 and the last on that day a Briton at 2100. A total of 75 survivors and one body were received on August 14, one more survivor on August 16, and the final two injured the following day. The greatest number delivered at any one time to the casualty entrance to the sick bay was 13 and fortunately injuries were slight, only two survivors requiring immediate hospital care.
The Health of the Navy in 1978
Authors: Harper M. G.
Published: October 2021

This paper summarises the 1978 Health of the Navy Report. It is based on the 1978 In-patient Record Summary (F. Med. 14) returns and provides an analysis of the health indicators used in previous reports to assess the health of the Navy for the major International Classification of Disease (ICD) categories and some specific diseases. The paper concludes that, based on these parameters, the health of the Navy continues to improve although no account has been taken of minor morbidity, or social, cultural and psychological factors.
Thermal Stress and the Contribution of Radiant Heat
Authors: Smith D. J.
Published: October 2021

Sixteen young, healthy volunteers were exposed to eight thermally severe environments, each subject being exposed to four different climates. Four climates had a radiant heat component; globe temperature some 10°C above dry bulb. In the other four climates, the globe temperature was close to the dry bulb. Measurements of endurance time in the different climates were made, as were changes in deep body temperature and heart rate. The relationship between the wet bulb globe thermometer index (WBGT) and stay times in the non-radiant climates agreed well with that of previous workers. Further, the WBGT index appeared adequate, in the situation under study, in terms of its ability to quantify climatic severity, thermal and cardiovascular stress and hence endurance in climates with a high radiant heat component.
Care of Service Children on the Gosport Peninsula
Authors: Kershaw C. R. , Vincent S. H.
Published: October 2021

In this article we review the evidence which indicates that children from naval families may be more prone to problems relating to their health, development and behaviour than their civilian counterparts. The responsibility for the care of these children is shared between naval and civilian agencies, but traditionally the Royal Navy has had a special involvement in the care of children on the Gosport peninsula. As the problems have become more widely appreciated limited staff and facilities have been made available. A new move has been made to integrate the hospital services at the Royal Naval Hospital Haslar with those of Royal Naval and civilian agencies in the Rowner married quarters estate. It is intended to place a more positive emphasis on the care and development of children with handicaps and those under five and to encourage realistic support and self-help for naval families in the community during the 1980s.
Peptic Ulcer in the Royal Navy
Authors: Hunt R. H.
Published: October 2021

Peptic ulcer disease has been a major problem in the Royal Navy for more than 50 years. During the past decade specialist gastroenterology services have been established in an attempt to conserve and retain manpower skills. Fibreoptic endoscopy now provides rapid and accurate diagnosis while treatment with the new H2 receptor antagonists permits safe and effective therapy for the sailor both outside hospital and often now while still at sea. Changes in surgical techniques and a combined medical/surgical policy towards the peptic ulcer patient have also contributed to a coordinated programme.

The result of these changes has been a reduction in hospital admissions for duodenal ulcer, in the number of days of work lost from peptic ulcer disease, and a decline in the number of surgical operations for peptic ulcer at RNH Haslar. Invaliding of patients from the Royal Navy and Royal Marines for peptic ulcer disease has been almost abolished, emphasising the success of our policy of manpower conservation. Further work is required, however, to maintain patients in remission from their ulcer for longer periods and to identify better and earlier those patients who will ultimately require surgery.
Out-patient Treatment of Haemorrhoids
Authors: Leicester R. J.
Published: October 2021

The scope of out-patient treatment of haemorrhoids has been increased since the introduction by Barron in 19631 of rubber band ligation. This combined with conventional sclerotherapy can greatly reduce the number of hospital admissions for an extremely common condition.

In May 1979 a ‘Rectal Clinic’ was established at the Royal Naval Hospital Haslar, primarily for the treatment of haemorrhoids but also to allow a rapid referral service in the hope of detecting large bowel cancer at an earlier stage. During a one year period over 100 patients have been referred for treatment of haemorrhoids, of whom 66 have completed their course of therapy. A retrospective survey of 60 in-patients with haemorrhoids admitted over a similar period in the previous year was made for comparison. Only six patients have required operation since the clinic commenced.

Out-patient treatment has been found to give a better rate of symptomatic relief and resulted in a much shorter time away from work, without the considerable cost of hospitalisation. It is therefore recommended that such procedures should be more widely used in hospital practice.
The Prevention and Treatment of Alcoholism in the Royal Navy — 3. Preliminary Report on a Pilot Study of Naval Alcoholics
Authors: Hiles F. M. J.
Published: October 2021

Historical records contain many references to excessive drinking in the Royal Navy. It is apparent, however, that the prevalence of gross drunkenness has diminished greatly during the past two centuries. Nevertheless, there remain four main reasons for concern about naval drinking:

1.

Evidence of increasing alcohol consumption in the United Kingdom.

2.

Clearer definition of the limits of ‘sensible drinking’.

3.

Evidence of occupational risk factors, and

4.

The changing role of the sailor in a computer-age Navy.

Current Naval alcohol policy stresses a need for both preventive measures and early intervention in cases where evidence of abnormal drinking exists. In order to facilitate these measures a careful study of Naval drinking is required. Preliminary results from part of this project — a pilot study of 200 male Service alcoholics — confirm the presence of an alcoholdamaged group within the Service and establish baseline profiles of patients in treatment. The indications for further investigation, both in the treatment setting and in the Naval community, are outlined. Naval alcohol policy aims not only to enhance the efficiency of the work force but also to attend to the welfare of the individual sailor.
Adult Coeliac Disease — A Treatable Cause of Chronic Ill Health
Authors: Jarvis L. J. , Williams J. G.
Published: October 2021

Adult coeliac disease is a cause of chronic ill health that is probably much under-diagnosed. The presenting features may be vague and variable, and so indistinct as to allow a long period of minor ill health before the diagnosis is made. Nine cases of adult coeliac disease diagnosed and treated at RNH Plymouth are discussed to illustrate these points.
Spontaneous Intraperitoneal Rupture of Pyonephrosis
Authors: Leicester R. J.
Published: October 2021

Intraperitoneal rupture of a pyonephrosis is an extremely rare cause of generalised peritonitis. The nature of the lesion is usually unsuspected until found at operation or post-mortem. The case described is added to the 15 previously reported.
Stress Fractures at Commando Training Centre Royal Marines, Lympstone — A Retrospective Survey (September 1979 — October 1981)
Authors: Evans G. W. L.
Published: October 2021

The problem of stress fractures, both in general and in association with military training, is briefly reviewed. The results of a retrospective survey of 109 radiographically confirmed cases at Commando Training Centre Royal Marines Lympstone occurring over a period of 26 months are presented. These comprised 57 cases of metatarsal stress fracture, 44 cases of tibial stress fracture, three cases in the fibula, two cases in the os calcis, two in the femoral neck, and one affecting the inferior pubic ramus.

Some tentative conclusions regarding the aetiology, natural history and diagnosis of stress fractures are drawn: it is possible that increasing the average age of those undergoing commando training might reduce the incidence of stress fractures, but such a policy might well lead to other problems in training and should be advocated with caution, if at all. Otherwise no feasible suggestions for reducing the incidence can be made which are compatible with Service requirements.
The effect of cimetidine on pepsin secretion in patients with Zollinger Ellison Syndrome
Authors: Gledhill T. , Colley S. , Billings J. A. , Gray S. P. , Hunt R. H.
Published: October 2021

We have measured pepsin output in two patients with Zollinger Ellison Syndrome before and after an intravenous dose of cimetidine. Pepsin output increased after H2 blockade in both patients despite a decrease in both the volume and acidity of secretion. We suggest that nonresponse to cimetidine may be due to increased pepsin secretion when receiving treatment.
Assessment of ships taken up from trade and other ships for use as emergency facilities in wartime
Authors: Williams J. G. , Wilkes F. R. , Shouler P. J. , Jones P.
Published: October 2021

During the recent Falklands crisis SS Canberra was converted into a troopship with a hospital facility. Before hostilities began in earnest, other ships taken up from trade (STUFT), Royal Fleet Auxiliaries and warships were assessed as possible alternative sites for such a surgical facility. The requirements for such a conversion, and their application to Canberra, are described.
Ajax Bay
Authors: Jolly R. T.
Published: October 2021

As a result of fierce aerial attacks on the fleet supporting the landing force on Friday, 21 May 1982, SS Canberra was ordered to sail from San Carlos Water. Elements of her medical organisation were hurriedly put ashore into a deserted refrigeration plant at Ajax Bay. Three weeks later they had treated over 650 battle casualties, performed 210 operations under general anaesthetic, and been bombed by Argentinian aircraft. Despite appalling circumstances, their results were a triumphant success. As Officer Commanding Medical Squadron, Commando Logistics Regiment RM, the author was in charge at Ajax Bay throughout the land phase of hostilities.
Prescribing for the prevention of infective endocarditis: A study into the use of prophylactic antibiotics in the Armed Forces Dental Services
Authors: Woodman A. J.
Published: October 2021

A review of the rationale for the use of antibiotic prophylaxis to prevent the effects of bacteraemia associated with dental treatment is presented with the background to the development of currently recommended high-dose prescribing. The results of a survey within the Armed Services into the current use of antibiotic prophylaxis indicate a wide variety of prescribing schedules, mostly considered effective by accepted standards. However, the use of antibiotics when penicillin hypersensitivity exists was often associated with doses considered ineffective against bacteraemia. The readiness to prescribe repeated prophylaxis was indicative of a lack of awareness of the problems of resistance within the Services for oral prophylaxis which was provided for most medical conditions in a responsible manner. Most replies indicated that there was room for improvement in communication between the patient and medical and dental practitioners regarding the dental involvement in infective endocarditis.
Functional imaging in nuclear medicine—mathematical and physical aspects
Authors: Houston A. S.
Published: October 2021

Functional imaging has recently played a most important role in diagnosis in nuclear medicine. In this paper the mathematical concept is described and a variety of applications discussed.
Haslar Museum
Authors: Parsons C. T.
Published: October 2021

‘Art. 80. Haslar Museum. The museum at Haslar being on a different footing to that at the other Hospitals is to be divided into two parts, the pathological and the general, the former being kept for use by Medical Officers and Sick Berth Staff, and having a separte catalogue.’
Head injury and diving: A review
Authors: Green R. D. , Leitch D. R.
Published: October 2021

A number of prospective and trained divers experience head injury. The current guidelines for assessing these cases are inappropriate. This review was undertaken to clarify the issue. Head injury was considered in relation to possible complications in diving such as post-traumatic epilepsy, cerebral oxygen toxicity and decompression sickness. It was concluded that an injury resulting in not more than ten minutes unconsciousness and one hour of post traumatic amnesia without any localising signs would be acceptable. Head injury in trained divers should result in suspension of diving for three weeks. The significance of minor sequelae and linear skull fractures are also discussed. Ancillary investigations such as EEG are considered to be of little use.
The Telfer osteotomy for hallux valgus
Authors: Farquharson-Roberts M. A. , Osborne A. H.
Published: October 2021

One hundred and four cases of hallux valgus are presented all of whom underwent a greatly modified metatarsal osteotomy which has been developed by Surgeon Captain R C. Telfer, Royal Navy.
The effect of exposure to simulated ship fire-fighting spray systems on the transfer factor for the lung
Authors: Searing Caroline S. M. , Golden F St C
Published: October 2021

The effect of inhalation of sea water mists of four different intensities (10, 20, 30 and 40 1 m−2 min−1) from a firefighting sprinkler system was investigated in seven volunteer subjects. Measurements of transfer factor taken before and after exposure to the sprays showed no consistent changes. Those changes that were evident were more pronounced following exposure to the less intense sprays, but it was considered that these were attributable to diesel oil contamination on that occasion. The effects of aspiration of diesel contaminated water and the diurnal variation in transfer factor are discussed.
Training for the role of Staff Nurse—Professional and personal preparation of recently qualified Registered General Nurses in the QARNNS
Authors: Wellings P. R.
Published: October 2021

Recently qualified Registered General Nurses (RGN) in Queen Alexandra’s Royal Naval Nursing Service (QARNNS) undergo a four week management block prior to taking up Staff Nurse posts on the wards. The aim of the block is to introduce students to the principles of leadership and management, to foster an interest in world affairs and service matters, and to develop certain skills not included in the basic nurse training curriculum. An important secondary role of the block is to enable a proper assessment of the nurse’s managerial and leadership ability to be made, both real and potential. The development of the management block is discussed and the unusual assessment methods described.
Four cases of spinal cord compression: The need for early diagnosis
Authors: Bradley R. K. , Murch S. H.
Published: October 2021

Four cases of spinal cord compression, with symptoms and signs evolving over several years or as quickly as two days, are presented. The symptoms and signs of extrinsic cord compression are described and briefly contrasted with those of intrinsic cord or cauda equina lesions. The need for early clinical diagnosis is emphasised.
Caries activity in a sample of 25-year olds—Sugars or dentistry?
Authors: Alexander D. C. C.
Published: October 2021

A survey was performed in which the dental records of a sample of 25-year old RN personnel were analysed for increases in dental caries and restorative status since entry into the Service. Mean annual increments of 0.26 teeth and 0.74 surfaces occurred. The highest increases were found in the records of those who had served the longest, but the greatest number of courses of treatment occurred in those who on entry already had high caries scores. The possible causes of this continuing disease process are discussed and in conclusion it is put forward that dental health is being achieved in the Royal Navy by the treatment of disease by restorative dentistry rather than by the utilisation of proven and effective methods of prevention.
Sudden hearing loss due to coincident perilymph fistula and subluxation of the incudo-stapedial joint
Authors: Frampton M. C. , Counter R. T. , Garth R. J. N. , d’E Meredith A. P.
Published: October 2021

A case of deafness due to coincident perilymph fistula and subluxation of the incudo-stapedial joint is presented. Prompt surgical intervention confirmed the nature of the injury and repair resulted in a return to near normal hearing levels.
The first Antarctic winter in tents: The Joint Services Expedition to Brabant Island (Part 3)
Authors: Oakley E. H. N.
Published: October 2021

The final part of the account of this expedition describes experience and assessments of shelters, clothing, methods of travel, etc. Although the team lived throughout the winter in tents, a cardboard hut proved invaluable and easy to transport by air. The most robust design of tent was the Antarctic Pyramid, but this was not portable and proved cold in its lower regions. Lightweight dome tents were used for travelling, but needed protection from winds greater than 60 knots. Many different garments were taken. Although most were worn continuously for periods of three to nine months without their (or the underlying body) being washed, most performed very well. No subjective difference was observed between synthetic and natural fibre underwear in the face of these conditions. Foot and hand wear were less satisfactory. Insulation between body and ground was found to be very important in tents. Travel was largely achieved using ski-mountaineering techniques wearing rucsacs, and towing individual sledges (pulks). These enabled a lightweight, mobile and relatively cheap expedition, and should be considered for similar work in the future.
Actigraph measurements of work/sleep patterns during a Navy Operation
Authors: Brooks C. J. , Shergold D. J. , Redmond D. P. , Angus R. G. , Heslegrave R. J.
Published: October 2021

Crew sleep-wake patterns were investigated using the new technology of actigraphy. During a routine seven day coastal patrol in HMCS Saguenay, the devices were worn by 20 personnel; eight dayworkers, eight ‘rotating shift’ watchkeepers, and four senior crew. To assess the validity of actigraphic data the results were compared with subjective sleep reports. Analyses showed that the actigraphic estimates of sleep quantity exceeded the subjective estimates by about one hour for watchkeepers and senior crew. There was no difference between the two estimates for dayworkers. Reasons suggested for differences between actigraphic and subjective sleep quantity estimates are discussed. Further laboratory studies are required to determine threshold sleep values for the actigraph. Once these studies have been completed the actigraph will have great utility for helping to determine optimal work/rest/sleep regimes for operational environments.
Gender-specific side effects of chemotherapy in pancreatic cancer patients
Authors: De Francia Silvia , Mancardi Daniele , Berchialla Paola , Armando Tiziana , Storto Silvana , Allegra Sarah , Soave Giulia , Racca Silvia , Chiara Francesco , Carnovale Jennifer , Ciuffreda Libero , Mussa Maria Valentina
Published: October 2021

Pancreatic carcinoma incidence showed a significant increase in men over the last few years and the prognosis remains poor. Patients are treated with different pharmacological plans with no evidence about gender-specific adverse effects. We aimed to investigate differences in the incidence of chemotherapy side effects in the treatment of pancreatic cancer, to provide insights toward a personalized assistance based in individual needs. The sample population is composed of 207 patients. Regression model highlighted the predictive role of female gender for alopecia, constipation, hand-foot syndrome, and epigastric pain. Also, considering single therapeutic schemes, gender differences have been reported. Moreover, evaluating the effect of age, a general reduced risk of toxicity has been reported in younger patients. To personalize chemotherapy and increase patient survival rate and life quality during the therapy, gender medicine and pharmacology studies are recommended.
Design and Analysis of a Small-Size, Flag-Shape UWB Antenna with Dual Notch Band Using Mushroom Structure
Authors: Mandal Tapan , Mondal Pratik , Murmu Lakhindar
Published: October 2021

A small-size, flag-shaped microstrip-fed printed UWB antenna with dual notch band (NB) is investigated. The essence of flag configuration is evolved from the regular hexagon where both shapes provide UWB responses. Then, the WiMAX and WLAN notch bands are created by using electromagnetic bandgap (EBG) structures for avoiding potential interference. A microstrip line-based model is employed to investigate the NB characteristics of EBG. Various parameters, surface current distribution and input impedance are analyzed to understand the effects of the mushroom. The measured operating frequency of the proposed antenna is from 2.91[Formula: see text]GHz to 10.88[Formula: see text]GHz along with excellent rejection bands of 3.2–3.54[Formula: see text]GHz and 5.13–5.6[Formula: see text]GHz, respectively, for [Formula: see text][Formula: see text]dB. The experimental result has good correlation with the simulated one. The designed antenna exhibits minimal gain variation, appreciable efficiency, stable radiation patterns, transfer function and the time-domain study results correspond well to [Formula: see text] in the pass band. Therefore, satisfactory results ensure its ability to work as a UWB antenna.
SURFACE-ENHANCED RAMAN SCATTERING ACTIVITY OF PLASMONIC Ag–Ti NANOISLAND FILMS
Authors: PHAE-NGAM WUTTICHAI , RATTANA TANATTHA , SUJINNAPRAM SUPPHADATE , CHANANONNAWATHORN CHANUNTHORN , WAIWIJIT URAIWAN , HINCHEERANUN WANTANEE , KOWONG RATTANACHAI , HORPRATHUM MATI , LERTVANITHPHOL TOSSAPORN , VANIDSHOW WATCHARAPON , YUWASONTHI WEERAYA , CHOKBORIBAL JAROENPORN
Published: October 2021

Bimetallic nanostructure of noble metals is an alternative material that can provide the tenability of plasmonic performance. In this study, the plasmonic silver–titanium nanoisland (Ag–Ti NI) films deposited on a silicon wafer and glass slide substrates were prepared by magnetron co-sputtering of high-purity Ag target (99.99%) operated at 100 W-DC source, and Ti target (99.99%) operated at 50–250 W-DC pulsed source. The surface morphologies of the prepared films revealed a noncontinuous island Ag–Ti according to the formation of thin film growth based on the Volmer–Weber model. An increase in the sputtering power of the Ti target caused an evident increase in the Ag–Ti NIs diameter. The localized surface plasmon resonance (LSPR) was evaluated by UV–Vis–NIR spectrophotometry. The LSPR peak shift disappears with an increase of the sputtering power of the Ti target.In addition, the results confirmed that the surface-enhanced Raman scattering (SERS) activity of the bimetallic Ag–Ti NIs significantly improved in performance and stability, which is promising for the application in analytical chemistry.
Automated reasoning tools in GeoGebra discovery
Authors: Kovács Zoltán , Recio Tomás , Vélez M. Pilar
Published: October 2021

We present some current achievements in the software package GeoGebra Discovery that provides several symbolic tools and commands to mechanically discover (and verify symbolically) relationships on planar geometry constructions. Our presentation includes the novel Discover tool and command, the Relation tool and command, and the Compare command. Our proposal successfully makes the cycle 'conjecturing-checking-proving' in elementary geometry even more accessible for general users, focusing not only on educational uses but research as well.