Periodic Replacement Research Articles

Insights from a National Survey on Controlled Substance Diversion Practices in U.S. Hospital Pharmacies: Opportunities for Enhanced Surveillance and Compliance

This study explored controlled substance (CS) diversion surveillance practices within hospital pharmacies across the United States. A survey with questions based on published CS diversion risk points was conducted in May 2024. A total of 66 participants from 31 states responded, with 54.5% from single facilities and the remaining from health systems. Most respondents were pharmacy directors, managers, or those in dedicated drug diversion roles. Over 70% have dedicated surveillance teams and use drug diversion software. Results highlight variation in practices, with larger institutions generally showing better compliance. Compliance in procurement and receiving was high for access measures; however, auditing of processes was lower. The lowest procurement compliance was in monitoring periodic automatic replacement (PAR) levels and validating orders with wholesalers. Storage practices showed high compliance in deploying cameras, but low compliance in monitoring them. Dispensing practices had high compliance for restricting CS in automated dispensing cabinets, but low incidence of witness verification during stocking. Waste and disposal practices were well-followed, but training on detecting potential signs of medication tampering was less common. The survey highlights that while strategies to prevent CS diversion exist, their implementation varies. Enhancing monitoring, auditing, and training is essential to strengthen diversion prevention efforts in hospital pharmacies.

Optimal replacement policy for repairable products with multi-attempt minimal repair under the free-repair warranty

ABSTRACT This paper investigates the effects of unsuccessful repairs on the optimal periodic replacement policy for a repairable product with multiple attempts of minimal repair under the free-repair warranty. The motivation for this study is based on the novel notion of ‘multi-attempt minimal repair’, first introduced by Cha and Finkelstein (2024a, 2024b), in which they highlighted various practical reasons and examples to illustrate that minimal repair attempts may sometimes fail and need to be repeated until success is achieved. Their repair model and useful properties served as the motivation for this study. For both the warranted and non-warranted products, cost models are developed from the user’s perspective, and the corresponding optimal replacement policies are derived to minimize the long-run expected cost rates. By comparing these optimal policies, we show that the optimal planned time for preventive replacement should be adjusted toward the end of the warranty period, and the effects of unsuccessful minimal repair produce different degrees of impact, respectively, on the warranted and non-warranted product. Finally, detailed numerical examples and computation results illustrate our findings, and some insightful observations about practical and managerial implications are concluded.

Prolonged diagnostic journey in delayed-onset adenosine deaminase deficiency

Adenosine deaminase (ADA) deficiency typically presents as a severe combined immunodeficiency in early infancy, although its onset may be delayed in some cases. We encountered two patients diagnosed with ADA deficiency in adulthood. In addition to previously reported cases, we aimed to identify and characterize the clinical and immunological features associated with delayed- and late-onset ADA deficiency. Both patients presented with pneumonia and hypothyroidism during early childhood. The patients were subsequently treated with periodic immunoglobulin replacement and levothyroxine therapy. They experienced recurrent infections, including pneumonia and shingles, and were diagnosed with ADA deficiency in adulthood. A literature review revealed that patients diagnosed after the age of 10 years had a median interval of 18 years from disease onset to diagnosis. Patients with combined immunodeficiency and recurrent lower respiratory tract infections or autoimmune diseases require early measurement of ADA activity or genetic analysis.

Recovered Foam Impact Absorption Systems

The use of foam materials in environments where they come into contact with individuals often results in deterioration, necessitating periodic replacements to maintain safety and hygiene standards. Foam, a lightweight, porous plastic formed by aggregated bubbles, possesses excellent impact-absorbing properties; however, its inherent porosity and susceptibility to wear present challenges. This project aims to develop a technological application for repurposing spent polyurethane (PU) foam from leisure facilities into effective impact absorption systems. By focusing on the reuse of deteriorated foam materials, this initiative seeks to minimize environmental impact while leveraging their beneficial technical characteristics. Addressing issues related to foam degradation, this project endeavors to create sustainable solutions by reintegrating spent foam into new systems. This innovative approach promotes sustainability while enhancing safety through the provision of high-quality, impact-resistant elements. Ultimately, this work aims to contribute to environmental conservation and the advancement of effective impact protection measures in leisure facilities.

Development of an automated system for the purification of alkanolamine solutions

The alkanolamine solutions used in natural gas purification processes are inevitably degraded over time. This occurs due to accumulation of reaction products from the reactions with carbon dioxide, hydrogen sulphide, oxygen and other impurities present in the gas streams, as well as from thermal degradation. The degradation of solutions leads to the formation of thermostable compounds that not only reduce absorption efficiency, but also increase corrosive activity. Furthermore, part of the amine turns into a bound state and becomes ballast. The necessity of purification of alkanolamine solutions is becoming more and more urgent since the cost of maintaining efficient operation of gas treatment plants grows, and environmental safety requirements increase. Purification of solutions makes it possible to prolong their service life, reduce the cost of purchasing new reagents and reduce the negative impact on the equipment. In this work the method of anion-exchange technology of purification is used. Unlike vacuum distillation and electrodialysis, the considered technology does not require significant energy costs for generation and maintenance of vacuum, and heating of solutions, it can be easily integrated into the existing production process without any significant changes in the infrastructure. The described problem is relevant for Kazakhstan oil refineries, two of which use methyldiethanolamine, and one of which uses diethanolamine, and the existing practice of maintaining the operability of the systems is based on periodic replacement of part of the solution with pure amine. The development of automated systems for purification of such solutions makes it possible to significantly improve process control, minimise manual labour, and improve the overall economic efficiency of production.

The concept of microfiltration of hydraulic oil in rail vehicles

The article presents the issue of microfiltration of hydraulic oil from metallic impurities and water that deteriorate the properties of the oil. Tests carried out on oils have shown that periodic oil replacement in machines or vehicles in accordance with their maintenance documentation ensures that the system is emptied of 95% of impurities from the old oil before pouring the new one. The remaining part, i.e. 5% of impurities, together with the oil remaining on the walls of the pipes or inside other hydraulic devices, will mix with the new oil, reducing its cleanliness class. Periodic replacement of hydraulic oil will not allow for complete cleaning of the system. In extreme cases, poor oil condition may cause disruptions in the operation of the machine with the hydraulic system or its downtime for oil replacement or repair. Filtering the oil in the system while the machine is running will clean the oil from impurities and water, extend the oil's service life, without disabling the hydraulic system. The article includes, among others: The justification for the use of microfiltration of hydraulic oil with portable filtering devices in order to extend the service life of the oil until the next replacement is presented. The main purpose of the article is to present the methodology for testing hydraulic oil in accordance with the requirements of ISO, NAS and SAE in order to assign the oil to a given cleanliness class. Additionally, the results of testing the oil cleanliness class in various periods of operation of the machine with the hydraulic installation on a portable measuring device were presented.

Influence of the System Downtime Cost Rate on the Performance and Robustness of Periodic Inspection and Replacement and Quantitative Inspection and Replacement Maintenance Strategies Using Monte Carlo Method

Abstract This essay analyzes the crucial role of maintenance in production and service-oriented enterprises, highlighting the necessity for integrated viewpoints in contemporary corporate management. Focusing on time-based maintenance (TBM) and condition-based maintenance (CBM) techniques, the study provides a novel criteria and applies Monte Carlo simulation for assessment. The purpose is to discover ideal values for the system downtime cost rate, establishing a balance between performance and resilience. The organized parts include deterioration and failure models, maintenance assumptions, and cost models, finishing with a summary of noteworthy results and recommendations for further investigations. The study brings significant insights into the subject of maintenance strategies and analyzes the influence of the system downtime cost rate on the performance and robustness of condition-based maintenance strategies for a system with more or less stable behavior.

Modification of Distillation Engines Using Used Oil into Diesel and Premium Fuel Using Circular Condensation

In the era of the industrial revolution which is very developed today, the automotive world is also increasing, especially in vehicles that are fueled by premium diesel, due to the increasing number of vehicle demand in the wider community as more and more innovations are issued to create something latest and new, From data (Central Statistics Agency 2020) vehicles on Indonesian roads from passenger cars, goods, motorcycles, buses reached 14. Behind the positive effects due to the increasing development of the automotive world, there are also negative effects, one of which is pollution and waste generated from vehicle lubricants, oil, from periodic replacements resulting from engine maintenance that must be carried out. So the author is interested in designing a distillation machine with a condenser to convert used oil into base oil (base oil gar reduces the negative impact, the method used is by literature review, field study, preparation and testing, although the results of the test were obtained from 3 samples, namely A, B, and C with different cooking times and temperatures, it was found that the physical results obtained were too different from each other, However, not with the content in the sample, which was tested using (GC-MS) it was found that compounds with different amounts were found, namely sample A with 48 compounds, Sample B with 42 compounds and Sample C with 68 compounds, the most compounds were found in the sample with the highest cooking time and temperature with a time of 160 minutes and a temperature of 254 °C. It was found that only sample A had a premium characteristic, namely the compound octane. So that this research can be used in the community.

Experimental Analysis of the Mechanical Characteristics of Vinyl Ester Composites Reinforced with Sisal Fiber for Prosthetic Socket

This research explores the scope of natural fibers for prosthetic socket application. A variety of conditions including maladies, accidents, and genetic disorders, necessitate the adoption of prosthetic organs. The human body undergoes significant physiological changes over time due to factors such as growth, weight fluctuations, and the periodic replacement and adjustment of appendages. In this study, biocomposite materials are fabricated using vacuum bag technology, with sisal fibers reinforced in vinyl ester at five different weight percentages: 0%, 5%, 10%, 15%, and 20%. Mechanical characteristics are determined through destructive testing, including flexural, tensile, impact strength, and hardness measurements according to ASTM standards. Scanning electron microscopy (SEM) analysis is employed to assess factrography and bonding properties. Results indicate that the biocomposite with 15% sisal reinforcement exhibited superior tensile and impact resistance compared to other compositions and matrices. However, at the expense of impact strength, the 20% sisal-reinforced vinyl ester increased hardness and flexural strength by 47% and 27%, respectively. This research aims to expand natural fibers and their utility in biomaterial applications, outlining points for elaboration and enhancement in this field, along with addressing associated challenges.

Effects of Rotenone Exposure on Apoptosis in rAAV-NDI1-infected Neural Stem Cell Line of Minipig

Background: The overall objective of this study is to confirm that normal expression of yeast NADH- dehydrogenase (NDI1) can occur in neural stem cell lines of minipig with resistance to rotenone exposure, an environmental factor responsible for dysfunction of mitochondrial enzyme complex I. In modern society, there are many diseases that cannot be treated. Diseases including LHON, Parkinson disease and dystonia, have been associated with defects in mitochondrial complexes. This experiment was performed to demonstrate that it was not sensitive. The overall objective of this study is to confirm that normal expression of yeast NADH-dehydrogenase (NDI1) can occur in neural stem cell lines of minipig with resistance to rotenone exposure, an environmental factor responsible for dysfunction of mitochondrial enzyme complex I. Methods: A Mini Pig Neural stem cell line (MPV) was used for transfection of the NDI gene, DMEM/F-12 culture medium and MPV was inoculated in a six-well plate (Corning, USA) at a concentration of 1×105 cells/3ml/well, with inoculation of MPV at 37°C for 24 hours, 5% CO2, followed by incubation in an incubator with 95% humidity and attached. The plate containing MPV cells was treated with recombinant adeno-associated virus ndi1 (rAAV-ndi1) for transfection, with periodic replacement with a cell selection culture solution containing 10% FBS, 1% P/S and 0.2 mM rotenone. The experiment was performed for restoration of mitochondrial activity of thawed cells. RNA was extracted from MPV cells and transfection of MPV cells with the NDI1 gene was performed using Trizol (Invitrogen, USA). Reverse transcription PCR (RT-PCR) and Western blot were performed to confirm normal expression of the NDI1 gene in MPV cells transfected with the NDI1 gene. Immunofluorescence was performed to determine the presence of the NDI1 protein in the cell and the cell count was used for LUNA and the rate of cell death for rotenone was determined using the MTS [3-(4,5-dimethylthiazol-2-yl)-5- (3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assay. Result: rAAV-NDI1 was successfully introduced into MPV cells and the proliferation rates for the cells were compared with those of the transformed cells; after three days, the non-infected cells were killed and the infected cells proliferated. The results after differentiating the cell lines were similar to those of previously reported studies. Toxicity analysis on rotenone was also performed using the MTS assay and the rates of cell death over three days were compared; the results showed significantly lower levels of NDI1-transformed minipig neural stem cells compared with those of minipig. The present work will be a complementary contribution to the comprehensive study of the scorpion sting syndrome. These results were similar to those of previously reported studies. Previous studies have reported that oxidoreductive stress can be a cause of apoptosis. Therefore, conduct of additional studies for measurement of ROS and oxygen utilization to determine oxidative stress in cells will be necessary.

Advanced Energy Harvesters and Energy Storage for Powering Wearable and Implantable Medical Devices.

Wearable and implantable active medical devices (WIMDs) are transformative solutions for improving healthcare, offering continuous health monitoring, early disease detection, targeted treatments, personalized medicine, and connected health capabilities. Commercialized WIMDs use primary or rechargeable batteries to power their sensing, actuation, stimulation, and communication functions, and periodic battery replacements of implanted active medical devices pose major risks of surgical infections or inconvenience to users. Addressing the energy source challenge is critical for meeting the growing demand of the WIMD market that is reaching valuations in the tens of billions of dollars. This review critically assesses the recent advances in energy harvesting and storage technologies that can potentially eliminate the need for battery replacements. With a key focus on advanced materials that can enable energy harvesters to meet the energy needs of WIMDs, this review examines the crucial roles of advanced materials in improving the efficiencies of energy harvesters, wireless charging, and energy storage devices. This review concludes by highlighting the key challenges and opportunities in advanced materials necessary to achieve the vision of self-powered wearable and implantable active medical devices, eliminating the risks associated with surgical battery replacement and the inconvenience of frequent manual recharging.

Diversification of Camphorosmeae (Amaranthaceae s.l.) during the Miocene-Pliocene aridification of inland Australia

The Australian Camphorosmeae represent a monophyletic lineage that diversified to include ca. 150 spp. across 12 genera, and populate large parts of arid Australia. Tracking the origin and spread of this ancestrally salt and drought tolerant lineage provides additional evidence about the timing of the evolutionary history and phylogenetic assembly of arid habitats in Australia. Using a customized RADseq approach, sequence data for 104 species of the Australian Camphorosmeae representing all 12 genera were generated and included in phylogenetic and dating analyses. Furthermore, habitat type occurrences and preferences of species and clades were recorded. As suspected, the characters used to delimit current Australian Camphorosmeae genera do not support monophyletic groups, as phylogenetic analyses yielded 17 statistically supported clades across a large Maireana grade and crown radiation of Sclerolaena. The diversification of Australian Camphorosmeae is clearly linked to landscape changes and emerging new habitat types in arid Australia since the ancestral element likely arrived from temperate semi-arid to arid parts of continental Eurasia in the Middle Miocene. Migration was likely multidirectional and followed a west-to-east aridification. Crown group diversification was strongest during the Pliocene and likely promoted by the west-to-east expansion of Riverine Desert habitats and subsequent expansion and colonization of newly developing arid habitats. Rapid range expansion, fast habitat saturation, as well as periodic expansion, contraction and replacement of arid habitats, may have caused the rather species-poor clades of the earlier-divergent Maireana grade, compared to the continuously diversifying Sclerolaena clade.

Restorative pyric herbivory practices in shrub-encroached grasslands enhance nutrient resource availability and spatial heterogeneity

Pyric herbivory (PH), the combination of prescribed burnings and targeted herbivory, is a promising tool for landscape restoration that emulates historical disturbance regimes. Nitrogen (N) and phosphorus (P) are crucial nutrients for plant growth and although several studies have analysed the single effects of fire or grazers in their availability, the combined effect of both disturbances in the soil nutrient budgets have been rarely considered. This research was planned to analyse the 2-year impact of PH restoration practices on the availability of N and P in two Ulex gallii-encroached grasslands in the Pyrenees. We monitored available forms of N and P for two years using periodic replacements of ion exchange resins to test the hypothesis that mid-term effect of targeted grazing was more relevant than short-term effect of burning. Additionally, we investigated the role of temperature and precipitation on nutrients accumulation and compared its significance to management factors. Burning transformed vegetation and litter into a spatially heterogeneous layer of ash and charred material, which resulted in a variable availability of N and P at the rhizosphere level. After two periods of PH, nutrient availability was higher in soils from grazed plots compared to ungrazed, and the impacts of early burns were scarcely discernible. Nitrate was found to be the most rainfall-dependent nutrient, and grazing also affected its spatial distribution. Our results suggest that the heterogeneous nutrient enrichment enhanced by PH is important for promoting the establishment of a diverse pool of plant species, including both N2-fixing and non-fixing species. In these rainy areas, the use of burnings alone, without grazing, may perpetuate the dynamics of N2-fixing shrub encroachment.

Planning maintenance when resources are limited: a study of periodic opportunistic replacement

Abstract Accepted by: M. Zied Babai We study an aged-based replacement policy with two control limits. The first triggers opportunistic replacement and the second triggers a guaranteed replacement. The policy is novel because: the instances for component replacement are restricted to instances of time, which we call slots, that arise periodically; and a slot provides an opportunity for replacement with a particular probability. The policy models contexts in which maintenance is periodic, and resources are limited or execution of maintenance is not guaranteed. The policy is important for practice because it is simple and reflects the common reality of time-based maintenance planning. Long-run cost per unit time and average availability are calculated in a renewal-reward framework. Numerical study indicates that, if opportunities are rare, guaranteed replacement is beneficial and opportunities should be taken early in the life of a system. Using the policy, a maintainer can evaluate the cost–benefit of investing more resources to reduce the time between slots. Specific analysis and policy comparisons can be carried out using a web-application developed by the authors.

Recent Advances in Wireless Optoelectronic Biomedical Implants

AbstractOptoelectronic implants have gained increasing attention over the last ten years for their clinical applications, such as optogenetics, photodynamic therapy, and deep‐tissue physiological sensing, which are expected to diagnose and treat a large number of diseases, such as Parkinson's and Alzheimer's diseases, visual impairment, and cancer. One of the main challenges for biomedical optoelectronics is to produce a compact, biocompatible system that delivers optical energy into specific tissue regions. While early‐stage devices are initially adopting batteries or wired solutions for energy supply, recent development has shifted toward wireless devices based on alternative methods, such as wireless power transmission, kinetic energy, and photovoltaic harvesting, which do not normally require periodic replacement or servicing and do not constrain the movement of the patient. In this paper, the principles of the main biomedical applications of implantable optoelectronic devices are reviewed. Recent developments in wireless implantable optoelectronic devices are summarized and sorted by their energy transfer mechanisms. These energy transfer techniques are compared in terms of quantitative parameters (electrical power, optical power, operating frequency, size, weight, and operating range), application fields where they are tested, and main advantages and limitations.

СОВЕРШЕНСТВОВАНИЕ СИСТЕМЫ РЕМОНТА И ТЕХНИЧЕСКОГО ОБСЛУЖИВАНИЯ ПАССАЖИРСКИХ ВАГОНОВ ДАЛЬНЕГО СООБЩЕНИЯ

The existing systems of maintenance and scheduled preventive maintenance of passenger rolling stock used for long-distance passenger traffic with speeds up to 140 km/h are considered. Promising areas for their improvement are identified. A combined repair system is proposed, which provides a uniform approach of the rolling stock to the position of a single technical audit and scheduled preventive maintenance without taking into account its mileage. The replacement of the element base, when the mileage criteria are met, is carried out on repair and equipment tracks or specially equipped positions during the technical preparation of the rolling stock at the initial point. The proposed system, in comparison with existing ones, reduces the need for depot repairs; the cost of carrying out scheduled repairs of cars, the time spent by cars in an idle fleet, and also provides opportunities for additional operation of the car at the operational stage of the life cycle. Also, the proposed system allows regulating the frequency of the element base replacement of passenger cars with a designated service life of 40 years, including them in the mandatory requirements for the necessary periodic replacement during capital repairs of the car every 5 years.

Evaluation of the Degree of Degradation of Brake Pad Friction Surfaces Using Image Processing

The improvement of drilling rig systems to ensure a reduction in unproductive time spent on lowering and lifting operations for replacing drilling tools and restoring the performance of drilling equipment units is an important task. At the same time, considerable attention is paid to the reliable and efficient operation of the braking systems of drilling rig winches. In the process of operation, the polymer pads periodically come into contact with the outer cylindrical surface of the metal pulley during braking, work in extreme conditions and wear out intensively, so they need periodic replacement. Tests were carried out on a modernized stand and in industrial conditions for the brakes of drilling winches. A methodology for evaluating the degradation of the brake pad friction surface during its operation is proposed. The assessment of the degradation degree is carried out based on the image of the brake pad surface using image processing techniques. Geometric transformations of the input image were performed to avoid perspective distortions caused by the concave shape of the brake pads and the spatial angle at which the image is acquired to avoid glares. The crack detection step was implemented based on the scale-space theory, followed by contour detection and skeletonization. The ratios of the area and perimeter of segmented and skeletonized cracks to the total area were chosen as integral characteristics of the degradation degree. With the help of scanning electron microscopy, the character of the destruction of the friction surface and the degradation of the polymer material was investigated. Experimental studies were performed, and the application of the proposed method is illustrated.

Development of modular cleaning complexes water of the north crimea canal for watering agricultural crops

In the market of equipment for irrigation of agricultural crops, a significant number of imported filters are sold at a fairly high cost, the loading of which requires constant regeneration and periodic replacement. With the resumption of water supply through the North Crimean Canal and thanks to government investments in agriculture of the Republic of Crimea, the development of compact filtration structures designed to purify irrigation water is relevant.

Omuz İmplantı Sınıflandırmasında Görü Dönüştürücü Tabanlı Modellerin Performans Karşılaştırması

Total Shoulder Arthroplasty (TSA) is a surgical procedure addressing severe pain and restricted shoulder joint movement. During TSA surgery, X-ray images guide the selection of the prosthetic implant suitable for the patient from a variety of models produced by different manufacturers. However, prostheses may wear or loosen over time, thus requiring periodic evaluation and replacement. Currently, the process involves taking new X-ray images from patients, resulting in variability in expert opinions on implant types. Automated systems can provide objective assessments, saving time and effort. In this study, we present a performance comparison of Vision Transformer (ViT) based models for automatic shoulder implant classification from X-ray images. Fine-tuning pre-trained ViT models on a shared dataset showed high success in accuracy, precision, sensitivity, and F-measure metrics. This approach can provide reliable identification of shoulder implant manufacturers and model information and time efficiency, especially for specialists, contributing to improving treatment planning.

Improving Best Practices in Assessing the Usage Conditions of Hospital and Long-Term Care Mattresses

Background: Inadequate mattresses can pose risks to users, and the routine inspection of mattresses often falls short in various healthcare settings. Objectives: To evaluate the physical condition of mattresses in hospitals and long-term care facilities and to explore the association with management practices regarding procurement, handling, and maintenance. Methods: This analytical descriptive cross-sectional study was conducted in 13 hospitals and 5 long-term care facilities, examining a total of 278 mattresses through proportional stratified sampling. The Mann-Whitney U test, Kruskal-Wallis test, and Multiple Regression Analysis were utilized for data analysis. Results: Only 9.9% of the mattresses met the physical evaluation criteria, highlighting a significant gap in mattress management standardization. The highest compliance was noted in the utilization of waterproof coverings, whereas the lowest was in mattress labeling. Factors significantly influencing the scores included the involvement of nurses in the evaluation process, periodic replacement of coverings, type of administration, assessment of mattress and covering integrity during bed making, and the nature of the institution. Conclusions: Due to inadequate physical conditions in both hospital and long-term care settings, the low approval rate of mattresses underscores the urgent need for standardized mattress management practices. Descriptors: Beds, Hospital Infection, Disinfection, Long-Term Care Facilities for the Elderly, Patient Safety.