bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.
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

ObjectivesWe 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 participantsWe 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 measuresParticipants 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.ResultsEvidence 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.ConclusionsWe 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

AbstractOn 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

AbstractThis 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

AbstractSixteen 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

SummaryIn 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

AbstractPeptic 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

ABSTRACTThe 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

ABSTRACTHistorical 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, and4.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

AbstractAdult 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.
Stress Fractures at Commando Training Centre Royal Marines, Lympstone — A Retrospective Survey (September 1979 — October 1981)
Authors: Evans G. W. L. 
Published: October 2021

AbstractThe 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

SummaryWe 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

SummaryDuring 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

SummaryAs 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

SummaryA 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.