Original Design Research Articles

An Innovative New Approach to Light Pollution Measurement by Drone

The study of light pollution is a relatively new and specific field of measurement. The current literature is dominated by articles that describe the use of ground and satellite data as a source of information on light pollution. However, there is a need to study the phenomenon on a microscale, i.e., locally within small locations such as housing estates, parks, buildings, or even inside buildings. Therefore, there is an important need to measure light pollution at a lower level, at the low level of the skyline. In this paper, the authors present a new drone design for light pollution measurement. A completely new original design for an unmanned platform for light pollution measurement is presented, which is adapted to mount custom sensors (not originally designed to be mounted on a unmanned aerial vehicles) allowing registration in the nadir and zenith directions. The application and use of traditional photometric sensors in the new configuration, such as the spectrometer and the sky quality meter (SQM), is presented. A multispectral camera for nighttime measurements, a calibrated visible-light camera, is used. The results of the unmanned aerial vehicle (UAV) are generated products that allow the visualisation of multimodal photometric data together with the presence of a geographic coordinate system. This paper also presents the results from field experiments during which the light spectrum is measured with the installed sensors. As the results show, measurements at night, especially with multispectral cameras, allow the assessment of the spectrum emitted by street lamps, while the measurement of the sky quality depends on the flight height only up to a 10 m above ground level.

Yeast diversity in Brazilian artisanal cheeses: Unveiling technologically relevant species to improve traditional cheese production

Although less studied than bacterial biota, the presence of yeast during the artisanal cheese’s production is of fundamental importance. Yeasts can prevent the growth of undesirable species in the cheese’s core and surface and actively participate in the aromatic development of these products. On the other hand, reintroducing the most abundant yeast species can help mitigate potential health risks related to artisanal production. The main objective of this study was to carry out an extensive mapping of the cultivable yeast diversity present in the central Brazilian artisanal cheeses (n = 582 cheese samples). Torulasporadelbrueckii, Candidaparapsilosis, Candidazeylanoides, Yarrowialipolytica, Debaryomycesprosopidis, and Kluyveromyceslactis were amongst the 300 clusters detected, respectively. In Canastra, Cerrado, and Serro-type cheeses, the predominant species was T.delbrueckii, while in Coalho and Manteiga cheeses, Y.lipolytica was the main species detected. The findings of this study reveal the yeast cultivable diversity present in a large set of Brazilian artisanal cheeses. Furthermore, these data can serve as a basis for promoting new Brazilian origin designation policies based on microbiological data.

Flow induced form: Shape optimization of bridge piers using CFD analyses and adjoint method

This study investigates the optimization of cylindrical bridge pier geometry using a relatively new technique involving Computational Fluid Dynamics (CFD) and adjoint shape optimization methods. Initially, Reynolds Averaged Navier-Stokes (RANS) equations were used in CFD models, integrated with an adjoint algorithm to reshape the pier and reduce bed shear stress. This approach is hereinafter called the “Flow induced Form”, FiF, aiming to minimize shear stress on the bed while maintaining the pier's cross-sectional and projected areas in the flow direction. Subsequently, Large Eddy Simulation (LES) transient analyses assessed the performance of the optimized geometry. Results show a reduction of approximately 5% in the time average of maximum shear stresses on the bed and a reduction of around 50% in instantaneous maximum values compared to the original pier design. These improvements were achieved with minimal changes to the cross-sectional area and projected area of the original geometry (∼2%), considering that the load-bearing capacity of the bridge pier.

Dynamic Characteristics of a 1950s Heritage Building: A Comparison of Original Design Methods and Modern Techniques

Research on design rules and methods for architectural heritage is an important aspect of conservation practice. Nevertheless, efforts to recover and divulge design methods for Modern Heritage remain limited. This paper is related to the recent structural assessment of a 15-storey heritage building built in 1950, during which a document describing the original seismic analysis of this structure was identified. The methodology employed is of particular interest, as it involves the application of pioneer concepts of dynamic analysis in the design of the first tall buildings in Mexico. The primary aim of this paper is to review the seismic design criteria for the case under study in order to contribute to the state of the art in Modern Heritage. The review includes a comparison between the dynamic characteristics estimated during the design and the results of recent ambient vibration tests and numerical modeling. Several sources of error among the design criteria were identified. Notably, the fundamental period estimated during the design was 38% larger than the experimental value due to an underestimation in stiffness, which introduces significant uncertainty into the design. Overall, the review shows the evolution of seismic analysis over time and provide valuable insights for the study of similar buildings.

Horseshoe effects on equine gait-A systematic scoping review.

To provide an overview of available research about effects of horseshoes on equine kinetics and kinematics. The terms, "horse/equine," "hoof," "shoes/horseshoes," "kinetics," and "kinematics" were searched in PubMed, Web of Science, Center for Agriculture and Bioscience International, and United States Department of Agriculture National Agricultural Library for manuscripts from first availability to 2024. Independent reviewers used preferred reporting items for systematic reviews and meta-analyses guidelines to map and extract evidence-based data from sources. Metrics included participant demographics, research methods, major findings, and study limitations. Knowledge gaps were also identified. A total of 46 studies were included. Most utilized non-lame horses to compare original shoe designs or modifications to unshod or a standard open-heel shoe. Horse demographics and gait, study design and outcome measures varied widely. Prevalent data collection equipment included force platforms and pressure plates, wearable force measuring technology, and videography. Many studies reported shoeing effects on limb forces and motion, but there was little consensus among unrelated studies. Common limitations included insufficient data resolution, no randomization, small sample size, single breed, and outcome measures specific or unique to the study. Knowledge gaps included data collection from all limbs and the impact of conformation and limb and hoof morphology and health condition on outcomes. Information from manuscripts that met inclusion criteria confirmed distinct, variable effects of shoe characteristics on equine gait parameters. Details from published work can serve as resource for clinical decisions and to guide standardization among investigations on shoe configuration effects on equine motion.

An approach to protected designation of origin (PDO) for bee honey utilizing the normalized difference vegetation index (NDVI)

ABSTRACT A methodology designed to monitor vegetation changes over multiple years in the vicinity of an apiary is presented. This approach relies on the utilization of the normalized difference vegetation index (NDVI). The findings of the analysis substantiate the viability of effectively tracking vegetation changes in a cost-efficient manner, thereby facilitating the determination of suitable geographical locations for obtaining protected designation of origin (PDO) status for bee honey. In this study, an apiary located in Malta was specifically examined for the production of Maltese autumn honey, which is harvested during December. The results conclusively showed that the vegetation surrounding the apiary remained highly stable between 2018 and 2022, providing strong evidence in support of the PDO status for the honey under examination. The proposed methodology is expected to greatly assist in the comprehensive evaluation of geographic areas for potential PDO logo. The detailed steps have been outlined, and additional studies utilizing diverse geographical regions and various types of honey are encouraged.

Study of the static response and zoning of the existing tunnel adjacent to the suspension bridge's tunnel-type anchorage

Due to the ability to utilize the strength of the surrounding rock to enhance bearing capacity, tunnel-type anchorages have been consistently utilized in suspension bridges. Nevertheless, a close interaction occurs between the tunnel and the tunnel-type anchor when a highway tunnel is connected to a suspension bridge. This study employed numerical simulation and theoretical analysis based on the G317 Line Huangjiayuan tunnel and Zipingpu Bridge tunnel-type anchorage project, focusing on this specific type of adjacent engineering. Firstly, the discriminant degree of adjacent influence suitable for the interaction between the tunnel-type anchorage and the tunnel structure is established. The calculation conditions are distinguished by the influencing factors determined in the discriminant. The interaction law between tunnel-type anchorage and pre-built tunnel structure is further obtained. Using the method of curve regression, based on the criterion of proximity influence degree, the partition of mutual influence degree between the tunnel-type anchorage and the tunnel structure is obtained. At the same time, it is concluded that under the original design condition, the displacement degree of the tunnel structure will be greatly affected, and the tunnel structure is located in the strong influence area. According to the partition result, under the benchmark engineering geological condition, it is suggested that the angle of intersection between tunnel anchorage and tunnel structure should be increased to 3.3° and the anchor body inclination should be increased to 44°.

Optimization of water supply parameters for enhanced thermal uniformity in aquaculture ponds under varied working conditions: An experimental study

Aquaculture ponds are critical for the successful rearing of fish larvae, and achieving consistent temperature distribution within these systems is essential for optimal growth conditions. This study explores methods for precise temperature regulation on both the water and atmospheric sides of the pond ecosystem. Based on the original design, systematic changes were made to parameters such as water supply pipe layout, bend angles, perforation rates, and working conditions. Metrics including average temperature, average temperature difference, and extreme temperature difference were utilized to extensively discuss the impacts of these parameters. Through this, temperature distributions across five distinct water supply layouts were analyzed, and the impacts of four different bending angles and perforation rates were evaluated using optimized configurations. Our findings demonstrate that a water supply layout radius of 2000 mm, coupled with a 60° bending angle and a 25 % perforation rate, increased overall temperature uniformity in the pond by 5 %. Additionally, seasonal variations significantly impact temperature distribution in ponds, particularly with different extreme temperature differences observed in winter and summer. Compared to the transitional season and summer, the average temperature difference in the pond during winter decreased by 30 % and 45 %, respectively. It was further revealed that winter conditions naturally yield more uniform water-side temperatures, making seasonal fluctuations irrelevant in determining optimal perforation rates. After the implementation of a water agitator, the average extreme temperature difference decreased from 0.6 K to 0.52 K. In the shallow water layer, the water agitator reduced the extreme temperature difference in the pond by 26 %. The use of water agitators has enhanced thermal uniformity in ponds, thereby improving the growth environment for fish larvae and providing valuable insights for environmental management in aquaculture.

ANALYZING THE IMPACT OF CONSTRUCTION DELAYS ON DISPUTES IN INDIA: A STATISTICAL AND MACHINE LEARNING APPROACH

In Major construction projects execution and performance were being negatively impacted by claims and disputes in terms of cost overrun, quality, stakeholders relationships, and productivity. Therefore understanding the significance of underlying the claims is essential. In this study, the primary root causes behind delay claims and disputes in construction projects were identified, examined, and rated. The significance of these factors was assessed using Relative Importance Index (RII) values. In addition, a machine learning model employing the Random Forest Genetic Algorithm (RFGA) was implemented to foresee the related risks and ascertain their levels. In a pilot survey, the data were collected across multiple construction projects at different phases such as scrutiny stage, design and planning stage, bidding stage, operation stage, and maintenance or after-construction stage. From Relative Important Index values from the statistical approach, it emerges that delay claims are generally causes from the owner followed by project-specific activities. Delays in processing bill payments, natural disasters, lack of contract awareness, and delay in final bill payment are the top causes of delay claims which converted to conflicts and disputes in mostly operating stage. The Random Forest Genetic Algorithm model predicted that factors like altering the original design, reluctance to cooperate by contractor, and increase of wages have lower risk whereas factors Poor site conditions, delay in approvals of schedules and change orders, natural calamities, late in running bill payment, repetition of work due to error in original work are at higher risk in terms of conflict and dispute. The model gives an accuracy of 0.89 and 0.87 for training data and testing data. The study will highlight possible research avenues and enhance project management strategies so that the project succeeds its goal.

Piezoelectrically and Capacitively Transduced Hybrid MEMS Resonator with Superior RF Performance and Enhanced Parasitic Mitigation by Low-Temperature Batch Fabrication

This study investigates a hybrid microelectromechanical system (MEMS) acoustic resonator through a hybrid approach to combine capacitive and piezoelectric transduction mechanisms, thus harnessing the advantages of both transducer technologies within a single device. By seamlessly integrating both piezoelectric and capacitive transducers, the newly designed hybrid resonators mitigate the limitations of capacitive and piezoelectric resonators. The unique hybrid configuration holds promise to significantly enhance overall device performance, particularly in terms of quality factor (Q-factor), insertion loss, and motional impedance. Moreover, the dual-transduction approach improves the signal-to-noise ratio and reduces feedthrough noise levels at higher frequencies. In this paper, the detailed design, complex fabrication processes, and thorough experimental validation are presented, demonstrating substantial performance enhancement potentials. A hybrid disk resonator with a single side-supporting anchor achieved an outstanding loaded Q-factor higher than 28,000 when operating under a capacitive drive and piezoelectric sense configuration. This is comparably higher than the measured Q-factor of 7600 for another disk resonator with two side-supporting anchors. The hybrid resonator exhibits a high Q-factor at its resonance frequency at 20 MHz, representing 2-fold improvement over the highest reported Q-factor for similar MEMS resonators in the literature. Also, the dual-transduction approach resulted in a more than 30 dB improvement in feedthrough suppression for devices with a 500 nm-thick ZnO layer, while hybrid resonators with a thicker piezoelectric layer of 1300 nm realized an even greater feedthrough suppression of more than 50 dB. The hybrid resonator integration strategy discussed offers an innovative solution for current and future advanced RF front-end applications, providing a versatile platform for future innovations in on-chip resonator technology. This work has the potential to lead to advancements in MEMS resonator technology, facilitating some significant improvements in multi-frequency and frequency agile RF applications through the original designs equipped with integrated capacitive and piezoelectric transduction mechanisms. The hybrid design also results in remarkable performance metrics, making it an ideal candidate for integrating next-generation wireless communication devices where size, cost, and energy efficiency are critical.

DEVELOPMENT OF NEW DESIGNS OF GP TYPE OIL-GAS BURNER DEVICES WITH NITROGEN OXIDES LOW EMISSION FOR OIL REFINERY FURNACES

The article discusses variants for new designs of GP type combined burner devices developed by the authors for oil refinery furnaces in order to reduce harmful emissions of toxic nitrogen oxides as one of the most dangerous chemicals. The main factors influencing the formation of nitrogen oxides during fuel combustion have been established. A classification of burner devices used in tube furnaces at oil refineries is given. Original designs of low-toxicity burner devices of the GP type, protected by patents for utility models differing from existing analogues in novelty and high environmental efficiency are recommended for implementation.

Leadership support and satisfaction of healthcare professionals in China’s leading hospitals: a cross-sectional study

BackgroundHealthcare professionals’ job satisfaction is a critical indicator of healthcare performance, pivotal in addressing challenges such as hospital quality outcomes, patient satisfaction, and staff retention rates. Existing evidence underscores the significant influence of healthcare leadership on job satisfaction. Our study aims to assess the impact of leadership support on the satisfaction of healthcare professionals, including physicians, nurses, and administrative staff, in China’s leading hospitals.MethodsA cross-sectional survey study was conducted on healthcare professionals in three leading hospitals in China from July to December 2021. These hospitals represent three regions in China with varying levels of social and economic development, one in the eastern region, one in the central region, and the third in the western region. Within each hospital, we employed a convenience sampling method to conduct a questionnaire survey involving 487 healthcare professionals. We assessed perceived leadership support across five dimensions: resource support, environmental support, decision support, research support, and innovation encouragement. Simultaneously, we measured satisfaction using the MSQ among healthcare professionals.ResultsThe overall satisfaction rate among surveyed healthcare professionals was 74.33%. Our study revealed significant support from senior leadership in hospitals for encouraging research (96.92%), inspiring innovation (96.30%), and fostering a positive work environment (93.63%). However, lower levels of support were perceived in decision-making (81.72%) and resource allocation (80.08%). Using binary logistic regression with satisfaction as the dependent variable and healthcare professionals’ perceived leadership support, hospital origin, job role, department, gender, age, education level, and professional designation as independent variables, the results indicated that support in resource provision (OR: 4.312, 95% CI: 2.412 ∼ 7.710) and environmental facilitation (OR: 4.052, 95% CI: 1.134 ∼ 14.471) significantly enhances healthcare personnel satisfaction.ConclusionThe findings underscore the critical role of leadership support in enhancing job satisfaction among healthcare professionals. For hospital administrators and policymakers, the study highlights the need to focus on three key dimensions: providing adequate resources, creating a supportive environment, and involving healthcare professionals in decision-making processes.

Optimization on distribution of high thermal conductivity materials in metal hydride reactor for improving heat transfer performance

The poor heat transfer performance significantly limits the reaction rate of hydrogen storage and release in metal hydrides reactors. In this work, the expanded graphite was used as high thermal conductivity materials (HTCMs), its optimal distribution in metal hydrides reactor was obtained by topology optimization method to enhance the heat transfer performance. Comparative studies on the hydrogen storage and release performance were conducted for the optimal HTCMs distribution model, uniform HTCMs distribution model, reconstructed model, and unimproved model to validate the optimization results. Finally, the effect of HTCMs contents was also studied. The results show that the optimization results shorten the hydrogen storage and release time by 32.3 % and 15.9 %, respectively, compared to the uniform distribution model. Besides, the proposed optimization scheme exhibits good performance under different HTCMs contents. When the content was set to 12 %, the optimized model reduces the hydrogen storage and release time by 28.5 % and 10.8 %, compared to the results of uniform distribution. The method and results of topology optimization have high reliability, and the HTCMs distribution designed by topology optimization has better hydrogen storage and release performance compared to original designs, it is widely applicable.

Elemental tracer determination and modeling for geographical origin designation of sweet oranges

Sweet oranges have long been an integral part of global health and culinary practices, offering a wealth of nutrients and bioactive compounds. Ensuring the authenticity of these citrus fruits is essential for maintaining consumer confidence, promoting transparency in sourcing, and protecting producers' reputations in the marketplace. In this study, we explored the feasibility of using multi-element profiling combined with pattern recognition algorithms to trace the origin of sweet orange samples. To achieve this, we employed an optimized microwave plasma atomic emission spectroscopy (MP-AES) method to analyze the elemental composition (Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, and Zn) of 183 orange samples from four production regions in northeastern Argentina. Support vector machine (SVM), random forest (RF), and gradient boosting tree (GBT) models were then built using the collected data to identify elemental tracer's indicative of origin. Based on a comprehensive evaluation of overall accuracy, receiver operating characteristic (ROC) curves, and area under the curve (AUC), the GBT model demonstrated the best classification performance, achieving a 96.5 % correct prediction rate on test samples, as confirmed by the ROC curve (AUC = 0.973). Consequently, this approach provides compelling evidence for the potential utility of MP-AES combined with supervised modeling to determine the geographic origin of sweet oranges produced in Argentina, thereby contributing to consumer protection against fraud.

‘Der Todtenkopf soll mir zu Ehren wegbleiben’: Ottilie Goethes Zuarbeiten für Anna Jameson

ABSTRACT This article examines Ottilie (von) Goethe's work for Anna Jameson and her preference for anonymity in the context of creative women’s struggle for self-determination. I ponder whether Goethe may have contributed illustrations in Jameson's anthology A Commonplace Book (1854), investigating for the first time their sources and, where applicable, previous discussion or publication: I can proof that the ‘Daughter of Fire’ and two compositions with cupids are reproductions of creations by the late-romantic painter Moritz von Schwind, a friend of Ottilie Goethe, while the statuette of an owlet on a youth's head from Johann Wolfgang Goethe's art collection as well as an enigmatic vignette of a skull are likely original designs. Goethe’s daughter-in-law can be connected with all three illustrations, and therefore she may have provided the drawings for the reproductions or at least have stimulated Jameson to include them in her illustrated book of excerpts, quotes, and new writings.

Fast Yet Effective Machine Unlearning.

Unlearning the data observed during the training of a machine learning (ML) model is an important task that can play a pivotal role in fortifying the privacy and security of ML-based applications. This article raises the following questions: 1) can we unlearn a single or multiple class(es) of data from an ML model without looking at the full training data even once? and 2) can we make the process of unlearning fast and scalable to large datasets, and generalize it to different deep networks? We introduce a novel machine unlearning framework with error-maximizing noise generation and impair-repair based weight manipulation that offers an efficient solution to the above questions. An error-maximizing noise matrix is learned for the class to be unlearned using the original model. The noise matrix is used to manipulate the model weights to unlearn the targeted class of data. We introduce impair and repair steps for a controlled manipulation of the network weights. In the impair step, the noise matrix along with a very high learning rate is used to induce sharp unlearning in the model. Thereafter, the repair step is used to regain the overall performance. With very few update steps, we show excellent unlearning while substantially retaining the overall model accuracy. Unlearning multiple classes requires a similar number of update steps as for a single class, making our approach scalable to large problems. Our method is quite efficient in comparison to the existing methods, works for multiclass unlearning, does not put any constraints on the original optimization mechanism or network design, and works well in both small and large-scale vision tasks. This work is an important step toward fast and easy implementation of unlearning in deep networks. Source code: https://github.com/vikram2000b/Fast-Machine-Unlearning.

Heat pipe type double-containment vessel as passive safety system for small modular reactors

This paper proposes a new concept of a passive safety system for small modular reactors as a heat pipe type double-containment vessel. The proposed system configures an additional vessel outside the existing one and functions as a heat pipe that utilizes phase change heat transfer to reduce the requirement of a large pool design. The double-containment vessel features a design consisting solely of the evaporation and condensation sections for heat pipe function with compactness. The ultimate heat sink only serves as a condenser part for the double-containment vessel, therefore significantly reducing the volume of stored fluid. The study numerically evaluates several postulated accidental cases to compare the performance of the double-containment vessel using the thermal hydraulic system code, MARS-KS. Even for serious conditions such as multiple failure accidents without safety systems operation, the double-containment can secure extra golden time to core damage by more than 2,090 sec compared to the original design. This study highlights the feasibility and potential of the heat pipe-based double-containment vessel as a passive safety system, enhancing the safety and reliability of small modular reactors. This kind of design can provide the advantages of safety and economics in the construction of small modular reactors.

Serviceability fragility assessment of non-seismically designed railway viaducts in Turkey under near-field and far-field earthquakes

While many railway viaducts still in use in Turkish railway networks are located on active fault zones that produced historical destructive earthquakes, they are not seismically designed in accordance to current standards. This study aims to provide a better understanding about the serviceability fragility of such systems by conducting detailed probability-based seismic assessments under near-field and far-field earthquakes. To achieve this, firstly, 3D finite element models of a range of selected viaducts in Turkey were generated based on their original design drawings. The developed FE models were validated by comparing the analytical modal frequencies with the results of in-situ dynamic tests involving a series of acceleration measurements. Nonlinear time history analyses were then carried out under 25 near-field and 25 far-field real three-component ground motion recordings to obtain the seismic response of each selected viaduct. Subsequently, probabilistic seismic demand models were defined using linear regression analysis to determine relationships between engineering demand parameters (EDPs) and ground motion intensity measures (IMs). Peak ground acceleration (PGA), peak ground velocity (PGV) and spectral acceleration at 1.0 s (Sa (1.0)) were used as the IM parameter, while the maximum lateral displacement of the bridge spans for different service velocities defined in the Eurocode was considered as the EDP at serviceability damage state. Finally, analytical fragility curves for all the selected railway viaducts were developed considering maximum damage probability for the IM levels. The results, in general, demonstrate the seismic vulnerability of the existing viaducts in Turkey. It is shown that while at low speed limits the viaducts exposed to far-field ground motions were more vulnerable than those under near-field ground motions, at high speed limits the viaducts subjected to near-field ground motions were more vulnerable. Also, it is seen that reinforced concrete and masonry viaducts are generally more vulnerable to earthquakes than the steel viaducts. The outcomes of this study should prove useful for the seismic risk assessment, loss estimation and rehabilitation of the railway transportation networks in future studies.

The long road to ignition: An eyewitness account

This paper reviews the many twists and turns in the long journey that culminated in ignition in late 2022 using the laser heated indirect-drive approach to imploding DT filled targets at the National Ignition Facility (NIF), located at the Lawrence Livermore National Laboratory (LLNL). We describe the early origins of the Laser Program at LLNL and key developments such as the paradigm shifting birth of high energy density physics (HEDP) studies with lasers, changes in choice of laser wavelength, and the development of key diagnostics and computer codes. Fulfilling the requirements of the multi-faceted Nova Technical Contract was a necessary condition for the approval of the NIF, but more importantly, the end of the Cold War and the cessation of nuclear testing were key catalysts in that approval, along with the ready-and-waiting field of HEDP. The inherent flexibility of the field of laser driven inertial confinement fusion played a fundamental role in achieving success at the NIF. We describe how the ultimately successful ignition target design evolved from the original “point design” target, through the lessons of experiment. All key aspects of that original design changed: The capsule's materials and size were changed; the hohlraum's materials, size, laser entrance hole size, and gas fills were also all changed, as were the laser pulse shapes that go along with all those changes. The philosophy to globally optimize performance for stability (by raising the adiabat and thus lowering the implosion convergence) was also key, as was progress in target fabrication, and in increasing NIF's energy output. The persistence of the research staff and the steadfast backing of our supporters were also necessary elements in this success. We gratefully acknowledge seven decades of researcher endeavors and four decades of the dedicated efforts of many hundreds of personnel across the globe who have participated in NIF construction, operation, target fabrication, diagnostic, and theoretical advances that have culminated in ignition.

Exploring versatile applications of a vacuum-assisted bone harvester in orthopedic surgery

BackgroundOrthopedic procedures often require removing bone or pathological tissue, with traditional methods involving instruments like curettes and rongeurs. However, these methods can be time-consuming and lead to increased blood loss. To mitigate these side effects, vacuum-assisted tools have been developed to aid in tissue removal. These devices enable surgeons to suction tissue without discarding it, potentially improving outcomes in conditions such as osteomyelitis or tumor removal while enabling collection of the material for downstream applications. Despite limited research, vacuum-assisted devices show promise beyond bone marrow harvesting. This study assesses infection and clearance rates, estimated blood loss, and total procedure time associated with the use of vacuum-assisted tissue removal, with a goal to understand if these devices can be used for tissue removal across a variety of pathologic conditions.MethodsA retrospective cohort study was conducted on patients undergoing orthopedic procedures with the Avitus® Bone Harvester repurposed from its original design from December 1, 2021, to July 1, 2023. Procedures were categorized into oncology, and debridement for infection cases. Infection cases were further categorized into those secondary to trauma and those involving primary infections (osteomyelitis and periprosthetic joint infection). Clinical variables, including demographics, intraoperative details, complications, and follow-up, were reviewed. Statistical analysis included descriptive statistics computed with R Studio.ResultsThe study included 44 patients, with debridement for infection cases being the most common (primary infection: 45.5%; infection secondary to trauma: 18.1%), followed by oncology cases (36.4%). In all oncology cases, a definitive diagnosis was established using the device, and no post-operative infections were reported. The infection clearance rate was 85.0% for primary infection cases and 50.0% for cases of infection following trauma. Across the entire cohort, the average blood loss was 314.52 mL (sd: 486.74), and the average total procedure time was 160.93 min (sd: 91.07). The overall reoperation rate was 47.7%, with an unplanned reoperation rate of 11.4%.ConclusionThe vacuum-assisted bone harvester was effectively utilized in a wide range of debridement and curettage procedures across diverse orthopedic surgeries. In oncology cases, the device enabled effective tissue removal with comparable recurrence rates, demonstrating its potential to minimize contamination while preserving tissue for accurate diagnoses. Additionally, a high rate of osteomyelitis eradication was observed in debridement for primary infection cases (85%). Despite the relatively high reoperation rate of 47.7%, it is crucial to interpret this figure within the context of the varied reasons for reoperation. Many of these reoperations were planned as part of a staged approach to treatment or were unrelated to the device's performance. It is crucial to acknowledge that isolating the device's contribution to these results can be difficult. The utilization of the device should be guided by considerations of cost-effectiveness and patient-specific risk factors.