Reduction Principle Research Articles

1762. A Review of Antibiotic Outcomes Data Utilizing the Multidisciplinary OPTIONS-DC Conference for PWUD

Abstract Background Persons who use drugs (PWUD) admitted for serious infections face many challenges when long courses of intravenous (IV) antibiotics are recommended. OPTIONS-DC is a structured multidisciplinary care conference used to navigate some of these challenges with harm reduction principles to consider patient preferences, decrease length of stay when safe, and support successful completion of antibiotics1. We aimed to describe antibiotic course outcomes 4 years after implementation of OPTIONS-DC. Methods We conducted a retrospective review of patients who had an OPTIONS-DC from February 2018 to February 2022. Any PWUD diagnosed with a serious infection requiring > 2 weeks of IV antibiotic treatment were eligible for an OPTIONS-DC. Data was collected via a REDCap database. R version 3.3.2 (R Core Team, 2016) was used for statistical analysis. Results 144 conferences were included, for 129 unique patients. The mean age was 39.4 with 56.3% being male. The most common infections were bacteremia (52.8%) endocarditis (36.1%), and osteomyelitis (47.9%) with a mean recommended treatment duration of 5.62 weeks (Table 1). 87 (60.4%) patients with any substance use initiated medication assisted therapy (MAT) during admission including 74.5% (79/106) of those with opioid use disorder. 112 (77.8%) antibiotic courses were completed with 71 (63.4%) completed outpatient. Of those who initiated or continued MAT during admission, 83 (74.1%) completed antibiotic therapy. Course completion was similar for those discharged home at 84% (21/25) or to a Skilled Nursing Facility (SNF) 81.8% (9/11). All 18 patients who received antibiotics via home infusion vendor and 17 (81%) via infusion center completed their course. 39 (39.8%) patients received long acting IV antibiotics and 23 (23.5%) received oral antibiotics to complete their course. Average out of hospital antibiotic days for those who completed their course were 30.5. Table 1.OPTIONS-DC Table 1Table 1.OPTIONS-DC Table 1 continued Conclusion The OPTIONS-DC model continues to be a useful tool by incorporating harm reduction principles and patient preferences for PWUD at our hospital. Our completion rate of 77.8% and outpatient completion rate of 63.4% are higher while the patient directed discharge rate of 8.3% is lower than what is generally reported in literature for this population2-5. Disclosures Monica K. Sikka, MD, F2G: Site research investigator.

Recent Advances and Perspectives of Core‐Shell Nanostructured Materials for Photocatalytic CO2 Reduction

Photocatalytic CO2 conversion into solar fuels is a promising technology to alleviate CO2 emissions and energy crises. The development of core-shell structured photocatalysts brings many benefits to the photocatalytic CO2 reduction process, such as high conversion efficiency, sufficient product selectivity, and endurable catalyst stability. Core-shell nanostructured materials with excellent physicochemical features take an irreplaceable position in the field of photocatalytic CO2 reduction. In this review, the recent development of core-shell materials applied for photocatalytic reduction of CO2 is introduced . First, the basic principle of photocatalytic CO2 reduction is introduced. In detail, the classification and synthesis techniques of core-shell catalysts are discussed. Furthermore, it is also emphasized that the excellent properties of the core-shell structure can greatly improve the activity, selectivity, and stability in the process of photocatalytic CO2 reduction. Hopefully, this paper can provide a favorable reference for the preparation of efficient photocatalysts for CO2 reduction.

Consumer alcohol policies in Switzerland: A case study of Migros supermarket group.

In June 2022, the Migros supermarket group in Switzerland declared the results of its referendum on the prospect of selling alcohol. Nationwide, individual members of the Federation of Regional Cooperatives that own the store had voted "No" to alcohol sales, thus continuing a philosophy that was implemented with its founding in the 1920s. As one of the biggest supermarket and convenience store chains in Switzerland, Migros is atypical in Western Europe for its alcohol-free consumer stance. However, this is complicated by the company selling alcohol in several of its retail subsidiaries and its stocking of alcohol-free beverages in own-brand shops. As such, Migros offers a distinctive and underexamined case study for wider drug policies and principles of prevention and harm reduction. This is especially notable within the framework of Switzerland's well-documented "four pillar" approach to substance use. Accordingly, in this article, we discuss the context of Migros' decision, issues raised by the referendum, and the significance of this consumer policy within Swiss society.

Community-Based Mental Health For Refugees: A Qualitative Study

<h3>Research Objectives</h3> To elicit in-depth feedback on a new, community-based mental health intervention for refugees living post resettlement in the USA to inform intervention development and the selection of culturally sensitive curriculum. <h3>Design</h3> Qualitative, focus group design. Three focus groups were conducted on Zoom in March of 2022. <h3>Setting</h3> This study was conducted virtually, in partnership with a community-based post-resettlement refugee agency in Providence, Rhode Island. <h3>Participants</h3> Eight refugees were purposively selected from the refugee agency. Participants had been resettled in the USA for between 6 months to 7 years (average = 3.5 years) and were from Angola, Afghanistan, Democratic Republic of Congo and Iraq. <h3>Interventions</h3> The in-development refugee mental health intervention consists of 10 modules, with curriculum on psychoeducation, Cognitive Behavioral Therapy (CBT) strategies and stress reduction principles. <h3>Main Outcome Measures</h3> Written and verbal feedback on the intervention content was used to generate qualitative themes on acceptability of the intervention. <h3>Results</h3> Participant feedback yielded four themes: 1) intervention needs unique to refugees unaddressed in current intervention 2) perceived benefits of the mental health intervention and application to refugee community 3) accessibility of intervention content and 4) intervention session logistics. Mental health during resettlement is impacted by a refugee's ability to establish a sense of stability and security while navigating a new physical, cultural and social environment; thus in addition to existing modules, refugees may benefit from additional content on navigating community systems (health, education, financial, etc.), American cultural norms, strategies for coping with social isolation and self-care practices. <h3>Conclusions</h3> Our study identifies areas to be included in a mental health intervention for refugees in the USA, highlighting cultural considerations for presenting written content and implementing sessions. <h3>Author(s) Disclosures</h3> No known conflicts.

Transitions in stochastic non-equilibrium systems: Efficient reduction and analysis

A central challenge in physics is to describe non-equilibrium systems driven by randomness, such as a randomly growing interface, or fluids subject to random fluctuations that account e.g. for local stresses and heat fluxes in the fluid which are not related to the velocity and temperature gradients. For deterministic systems with infinitely many degrees of freedom, normal form and center manifold theory have shown a prodigious efficiency to often completely characterize how the onset of linear instability translates into the emergence of nonlinear patterns, associated with genuine physical regimes. However, in presence of random fluctuations, the underlying reduction principle to the center manifold is seriously challenged due to large excursions caused by the noise, and the approach needs to be revisited.In this study, we present an alternative framework to cope with these difficulties exploiting the approximation theory of stochastic invariant manifolds, on one hand, and energy estimates measuring the defect of parameterization of the high-modes, on the other. To operate for fluid problems subject to stochastic stirring forces, these error estimates are derived under assumptions regarding dissipation effects brought by the high-modes in order to suitably counterbalance the loss of regularity due to the nonlinear terms. As a result, the approach enables us to predict, from reduced equations of the stochastic fluid problem, the occurrence in large probability of a stochastic analogue to the pitchfork bifurcation, as long as the noise's intensity and the eigenvalue's magnitude of the mildly unstable mode scale accordingly.In the case of SPDEs forced by a multiplicative noise in the orthogonal subspace of e.g. its mildly unstable mode, our parameterization formulas show that the noise gets transmitted to this mode via non-Markovian coefficients, and that the reduced equation is only stochastically driven by the latter. These coefficients depend explicitly on the noise path's history, and their memory content is self-consistently determined by the intensity of the random force and its interaction through the SPDE's nonlinear terms. Applications to a stochastic Rayleigh-Bénard problem are detailed, for which conditions for a stochastic pitchfork bifurcation (in large probability) to occur, are clarified.

Harm Reduction, Humanistic Psychology, and the CRPD

Harm reduction, which was initially developed as a public health response to illicit drug use, has relevance to the prescription of psychotropic medication. Indeed, focusing on the agency of people who use drugs—licit or illicit—facilitates a more authentic engagement with treatment. In this paper, we show how the framework of harm reduction is congruent with the guiding principles of both humanistic psychology and the Convention on the Rights of Persons with Disabilities (CRPD). Moreover, applying a harm reduction model to psychotropic drug use raises awareness that there are risks to taking these medications, risks which are frequently glossed over because of the emphasis on medication adherence and compliance. We provide case examples of organizations that take a person-centered (vs. medication-centered) approach to people experiencing mental health crises. In their unique ways, these organizations embody the principles of harm reduction and the humanistic impulse that informs the CRPD.

Design and Working Performance Evaluation of a Combined Survey Platform under Strong Wave and Deep-Water Conditions

To meet the engineering requirements of long-distance and high-precision elevation transfer under adverse sea conditions, a new structure for a combined survey platform based on the basic principle of vibration reduction and isolation is designed in this paper. The combined survey platform uses the barrier effect of the external support system on the wave-current load to reduce the influence of the wave-current load on the internal support system and the platform, so it can maintain good performance, even in harsh sea conditions, under the premise of no collision between the internal and external support systems. The expected working performance of the structure was verified by numerical simulation, and the influence of the layout, structure size, waves, and water flow on the working performance of the structure was quantitatively analyzed. The results show that: (1) the external support system can better realize the barrier effect of the wave-current load and significantly reduce the influence of the wave-current load on the internal support system and platform; (2) for the independent combined survey platform, when the pile diameters of the internal and external support systems are 0.8 m and 1.2 m and the wall thicknesses are 11.0 mm and 12.0 mm, respectively, the period of the wave is 8.0 s, the water depth is 20.0 m, the speed of water flow is 1.0 m/s, and the wave height is 4.0 m, then the maximum variation of the vertical angle of the platform is only 19.3″; (3) for the attached combined survey platform, the lateral stiffness of the external support system is increased and the displacement of the external support system is significantly reduced because the external support system is connected with the cushion cap through the attachments; therefore, the structure size of the survey platform can be greatly reduced.

Rank-based change-point analysis for long-range dependent time series

We consider change-point tests based on rank statistics to test for structural changes in long-range dependent observations. Under the hypothesis of stationary time series and under the assumption of a change with decreasing change-point height, the asymptotic distributions of corresponding test statistics are derived. For this, a uniform reduction principle for the sequential empirical process in a two-parameter Skorohod space equipped with a weighted supremum norm is proved. Moreover, we compare the efficiency of rank tests resulting from the consideration of different score functions. Under Gaussianity, the asymptotic relative efficiency of rank-based tests with respect to the CuSum test is 1, irrespective of the score function. Regarding the practical implementation of rank-based change-point tests, we suggest to combine self-normalized rank statistics with subsampling. The theoretical results are accompanied by simulation studies that, in particular, allow for a comparison of rank tests resulting from different score functions. With respect to the finite sample performance of rank-based change-point tests, the Van der Waerden rank test proves to be favorable in a broad range of situations. Finally, we analyze data sets from economy, hydrology, and network traffic monitoring in view of structural changes and compare our results to previous analysis of the data.

Triple three-phase permanent magnet synchronous motor with shaped magnets for low vibration applications

This paper presents a triple three-phase permanent magnet synchronous motor (PMSM) with shaped magnets for low vibration applications. Firstly, the features of the designed PMSM are investigated from three aspects, including triple three-phase windings, shaped magnets, and multi-layered housing. Then, the armature reaction, magnetomotive force, torque performance, and fault tolerance ability of the designed PMSM are investigated. Subsequently, the radial force of the designed PMSM with shaped magnets is studied, in which the radial force modulation effect is considered. In addition, the radial force and vibration reduction principle is elaborated in detail. The modal simulation and experiment are carried out, and the vibration reduction effect of the designed PMSM is verified by the multiphysics vibration predicted model. The result shows that the vibration can be effectively reduced by the shaped magnets and multi-layered housing design, and the output torque of the designed PMSM has been reduced insignificantly thanks to the triple three-phase windings.

Research on Waste Recycling Network Planning Based on the “Pipeline–Vehicle” Recycling Mode

To achieve the principles of reduction, resource, and harmless disposal of domestic waste, the circular economy prolongs the life cycle of resources by converting waste into renewable resources through sorting, recycling, and other ways. There are still noticeable problems in domestic waste recycling in China, such as poor waste classification and low recovery rate of resource-based waste with no or low economic value. In this paper, Van Waden’s seven-dimensional classification model of policy networks is adopted to analyze and compare domestic waste recycling (DWR) management modes at home and abroad. The domestic waste recycling mode of “pipeline collection and vehicle transfer” based on China’s national conditions is proposed. Then, the planning model of the domestic waste recycling network is further built. Taking Xiaolan Town, Zhongshan City as an example, the pipeline laying design and route planning of the pneumatic transportation and collection system for material in the new recycling mode are optimized. The examples verify the superiority of the greedy dropping heuristic algorithm in solving large-scale recycling network planning problems. This paper is of great significance to improve the recycling of renewable resources in domestic waste and realize the circular economy.

An Optimization Model for a Desert Railway Route Scheme Based on Interval Number and TOPSIS

The construction of desert railways inevitably destructs the environment and aggravates the wind–sand damage along the line. A reasonable railway route is an effective measure to avoid blown sand hazards, save construction costs, and reduce environmental damage. Currently, the selection methods for the railway route scheme are to analyze the qualitative indicators and quantitative indicators separately, and there are few decision-making models for the desert railway scheme. Therefore, this study aims to propose a comprehensive quantitative optimization model of the route scheme for the desert railway. Based on the design principles of hazard reduction, the evaluation index system of the desert railway route is first constructed, including railway design factors, wind-blown sand hazard factors, environmental impact factors, and operation condition factors. Subsequently, the subjective weights and objective weights are combined to obtain the comprehensive weights of the index by utilizing the principle of minimum discrimination information. Finally, the interval number is employed to quantify the linguistic fuzzy number of qualitative indicators, and the optimization model of the route scheme for the desert railway is constructed based on the technique for order preference by similarity to an ideal solution (TOPSIS). The model is verified using the Minfeng-Yuhu section in the Hotan–Ruoqiang railway as the case study. The achieved results reveal that this model enhances the accuracy and efficiency of the railway scheme decision-making and provides a theoretical basis for the optimal design and sand damage control of the desert railway.

Harm Reduction Principles in a Street Medicine Program: A Qualitative Study

There is ample evidence that homelessness is associated with high rates of morbidity and mortality. Street Medicine seeks to eliminate these disparities by providing healthcare on the streets to people who are unsheltered. While extant research describes health disparities for the unsheltered and programmatic approaches to addressing housing instability, there are few published studies describing how healthcare providers build and maintain relationships with patients on the street. This insight is central to specifying how street medicine differs from traditional forms of care and defining aspects of street medicine that contribute to successful patient engagement. Through a collaboration between Operation Safety Net (OSN), a street medicine provider in Pittsburgh, Pennsylvania, and [name redacted], an exploratory qualitative study was designed and implemented using harm reduction principles as a guiding framework. Qualitative interviews were conducted with eleven OSN street medicine providers and a thematic analysis using a deductive approach was used to analyze the data. Findings identified the ways that relational harm reduction was central to all aspects of patient care provided through this program. Major themes included: (1) individualism, or meeting patients where they are figuratively and literally; (2) humanism, which refers to valuing and holding true regard for patients; and (3) nonjudgmental care, in which providers do not hold negative attitudes toward patients and their decisions. These themes are consistent with relational principles of harm reduction. Challenges that were discussed also aligned with these principles and included frustration with systems providing care that did not meet patients’ individualized needs, and pain and trauma experienced by providers upon losing patients for whom they genuinely cared. Understanding these relational principles of harm reduction may help providers operationalize ways to effectively engage and maintain homeless patients in care and subsequently bridge the gap to traditional models of care. This study may provide valuable insights to expand the street medicine field in research and applied clinical and community settings.

35.3: Study on Technology to Enhance the Strength of Display Module for Vehicle

This paper studies a scheme to enhance the strength of display module, which can solve the problem of fragile cover plate of vehicle display and other display module products. The principle of strength reduction of glass after processing is analyzed from the perspectives of internal stress, microcrack and molecular bond. The technical scheme of using CeO2 aqueous adhesive solution to remove the longitudinal microcracks of glass reduce the deep expansion of crack source in the stress layer, so as to increase the strength is described. Based on the experimental results, the overall strength of the product can be increased by 23–34%.

Migration Behavior: the Effort Reduction Principle by G. Zipf

This article analyzes the legacy of one of the ‘classics’ of 20th centurymigration studies— George Zipf. Particular attention is paid to his work “Human behavior and the principle of last effort. An introduction to human ecology”. The authors focus not so much on the results of Zipf’s research, but on the questions he posed, and make the claim that these questions constitute the true value of Zipf’s scientific heritage. His inquiry on the criteria for describing migration process efficiency has become one of the key questions when it comes to theories of migration behavior, social adaptation and integration of migrants. The question about the influence of collective and group subjectivity on migration decision-making had a significant impact on the push and pull theory as formulated by E. Lee, while Zipf’s reflections on how migration behavior is influenced by the division of labor and the diversity of professional skills became the foundation for D.Massey's synthetic theory of migration. Step by step the article’s authors analyze Zipf's reflections in relation to such questions as: are migrants a social group? How can migration efficiency be measured? Is there a relationship between the movement of people and the movement of capital? How do the division of labor and the law of supply and demand affect migration? In conclusion, the authors formulate those theses brought forth by G.Zipf that are still relevant to this day.

A note on Etchemendy's and Prawitz's reduction principles for the Tarskian and model‐theoretic concept of consequence

AbstractOne of Etchemendy's arguments against the Tarskian and model‐theoretic notion of logical truth is based on a reduction principle according to which a universally quantified sentence is true if, and only if, all of its instances are logically true. The reduction of logical truth to mere truth reveals that the concept of validity at play in Tarski and in model‐theory relies upon extra‐logical assumptions. A similar reduction had already been put forward by Prawitz, although not with focus on extra‐logical assumptions. Prawitz's reduction concerns rather the possibility of understanding the Tarskian and model‐theoretic approach as implying any epistemic modality. We take into account a possible strategy that an advocate of Tarski and model‐theory may use against Etchemendy's objection, and argue that this strategy fails with respect to Prawitz's criticism. This permits us to shed light upon a difference between Prawitz's and Etchemendy's standpoints: while Etchemendy's reduction shows that the Tarskian and model‐theoretic notion of logical truth cannot be understood as an adequate formal counterpart of truth‐preservation solely by virtue of logical form, Prawitz's reduction insists on the fact that truth‐preservation solely by virtue of logical form is insufficient for epistemic modality to obtain.

Principles and practice: Towards disaster risk reduction in New South Wales, Australia

By ratifying the Sendai Framework for Disaster Risk Reduction (SFDRR), the Australian Government has accepted the need to mainstream disaster risk reduction (DRR) principles into policy and procedures. This research explores the extent to which this rhetoric has been actioned, using local-government policy as an indicator. The rationale for this approach is that evidence of DRR integration should be observable in recovery procedures related to the aftermath of disasters, which could extend over a period of years and require transformational changes. Using the targets and priorities of the SFDRR, a meta-synthesis of research conducted since its ratification was used to create a conceptual framework of DRR principles and practices. This framework was then used to conduct a policy analysis of the New South Wales Local Disaster Recovery Plan (NSWLDRP) template for alignment/non-alignment to the principles of the SFDRR, with the intention of indicating where future efforts in policy development should be directed.The analysis revealed gaps in intent between the NSWLDRP template and DRR principles and practices. While some underlying concepts of DRR are incorporated into the plan, such as vulnerability assessments and communication tools, fundamental risk reduction policies, including prevention, mitigation and participatory mechanisms are largely absent. This gap between the principles of the SFDRR and its limited application at the local level in NSW highlights the need for greater mainstreaming of DRR principles in both State and Federal Government frameworks since they direct both local disaster management arrangements and subsequent ongoing community development. The benefits of this includes reduced load on emergency services during extreme events, and increased community resilience after them, including reduced reconstruction and less disruption to community productivity in their aftermath.

Exploring Harm Reduction in Supportive Housing for Formerly Homeless Older Adults.

BackgroundExclusionary care policy contributes to the growing number of older adults experiencing homelessness and complex health challenges including substance misuse. The aim of this study was to examine how harm reduction policy and practices are experienced and enacted for older adults with homeless histories and care staff in congregate supportive housing.MethodsDrawing on harm reduction (HR) principles, Rhodes’ risk environment framework, and 15 semi-structured interviews (six residents, nine staff) at a 70-bed supportive housing facility in Western Canada, this qualitative constructivist grounded theory study aimed to determine: How is harm reduction experienced and enacted from the perspectives of older adults and their care staff?ResultsHR policy and practices helped residents to feel respected and a sense of belonging, due largely to staff’s understanding of structural vulnerability related to homelessness and their efforts to earn and maintain residents’ trust. Physical and program structures in the facility combined with the social environment to mitigate harms due to substance- and nonsubstance-related risk behaviours.ConclusionHR policy and practices in supportive living empower care providers and older adults to work together to improve housing and health stability. Wider adoption of HR approaches is needed to meet the needs of a growing number of older people experiencing homelessness and substance use challenges.

Volumetric Absorptive Microsampling (VAMS) for Targeted LC-MS/MS Determination of Tryptophan-Related Biomarkers.

L-Tryptophan (TRP) metabolites and related biomarkers play crucial roles in physiological functions, and their imbalances are implicated in central nervous system pathologies and neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), Alzheimer’s disease, Parkinson’s disease, schizophrenia and depression. The measurement of TRP metabolites and related biomarkers possesses great potential to elucidate the disease mechanisms, aid preclinical drug development, highlight potential therapeutic targets and evaluate the outcomes of therapeutic interventions. An effective, straightforward, sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of 24 TRP-related compounds in miniaturised murine whole blood samples. Sampling and sample pretreatment miniaturisation were achieved thanks to the development of a volumetric dried blood microsampling approach. Volumetric absorptive microsampling (VAMS) allows the accurate sampling of microvolumes of blood with advantages including, but not limited to, minimal sampling invasiveness, logistical improvements, method sustainability in terms of solvents and energy consumption, and improvement of animal studies in the framework of the 3Rs (Replacement, Reduction and Refinement) principles on animal welfare. The VAMS-LC-MS/MS method exhibited good selectivity, and correlation coefficient values for the calibration curves of each analyte were >0.9987. The limits of quantitation ranged from 0.1 to 25 ng/mL. The intra- and inter-day precisions in terms of RSD were <9.6%. All analytes were stable in whole blood VAMS samples stored at room temperature for at least 30 days with analyte losses < 14%. The developed method was successfully applied to the analysis of biological samples from mice, leading to the unambiguous determination of all the considered target analytes. This method can therefore be applied to analyse TRP metabolites and related biomarkers levels to monitor disease states, perform mechanistic studies and investigate the outcomes of therapeutic interventions.

The History of Surgical Stabilization of Rib Fractures (SSRF)

• The earliest account of open reduction and internal stabilization of rib fractures comes from Dr. Charles Locke Scudder in 1900 when he published, the treatment of fractures . • Surgical stabilization of rib fractures (SSRF) has evolved over 120 years with numerous advancements and lessons learned along the way. • Materials have evolved from sutures to wires to external and internal plates. • Rib fixation methods have evolved from open suture and wire cerclage to minimally invasive video assisted thoracoscopic surgery internal plating. Responsible for approximately 35% of all trauma-related deaths in the United States, thoracic trauma is one of the leading causes of death among trauma patients. Furthermore, traumatic rib fractures represent the most frequently encountered injury following thoracic trauma with mortality rates ranging from 8% among the elderly to 13% for patients with a flail chest. This manuscript reviews the history of SSRF as well as the contributions of the pioneering surgeons who championed this treatment. Rib fractures are a marker for severe injury as indicated by a recent National Trauma Data Bank (NTDB) retrospective analysis of 564,798 patients with one or more rib fractures. Approximately half of these patients were found to have multiple injuries with worse outcomes observed in patients with polytrauma and flail chest [1]. In addition, age, male gender, injury severity score (ISS), Glasgow Coma Scale (GCS), preexistent comorbidities, and number of rib fractures are independently associated with significantly higher rates of morbidity and mortality [1, 2]. Recently, studies have demonstrated surgical stabilization of rib fractures (SSRF) improves outcomes for ventilated as well as non-ventilated patients with flail chest, elderly patients, and select patients with multiple rib fractures without a flail injury or non-flail fracture pattern [2–6]. SSRF applies orthopedic principles of reduction and fixation to restore the architecture of the thoracic skeleton and re-establish normal respiratory physiology and minimize pain [7]. There has been a recent increase in prevalence of SSRF operations, however, SSRF is not a new technique, and progress has been anything but mundane or linear [3, 6]. This manuscript reviews the history of SSRF (Figure 1) as well as the contributions of the pioneering surgeons who championed this treatment. This review was conducted utilizing multiple national experts and a thorough literature review of related SSRF was performed. The sources chosen are considered by the authors to be highly influential and include the first publication for each distinctive method of SSRF.

An Evaluation of Different Types of Peptone as Partial Substitutes for Animal-derived Serum in Vero Cell Culture

Vero cells are one of the most frequently used cell types in virology. They can be used not only as a vehicle for the replication of viruses, but also as a model for investigating viral infectivity, cytopathology and vaccine production. There is increasing awareness of the need to limit the use of animal-derived components in cell culture media for a number of reasons, which include reducing the risk of contamination and decreasing costs related to the downstream processing of commercial products obtained via cell culture. The current study evaluates the use of protein hydrolysates (PHLs), also known as peptones, as partial substitutes for fetal bovine serum (FBS) in Vero cell culture. Eleven plant-based, two yeast-based, and three casein-based peptones were assessed, with different batches evaluated in the study. We tested the effects of three concentration ratios of FBS and peptone on Vero cell proliferation, four days after the initial cell seeding. Some of the tested peptones, when in combination with a minimal 1% level of FBS, supported cell proliferation rates equivalent to those achieved with 10% FBS. Collectively, our findings showed that plant-based peptones could represent promising options for the successful formulation of serum-reduced cell culture media for vaccine production. This is especially relevant in the context of the current COVID-19 pandemic, in view of the urgent need for SARS-CoV-2 virus production for certain types of vaccine. The current study contributes to the Three Rs principle of reduction, as well as addressing animal ethics concerns associated with FBS, by repurposing PHLs for use in cell culture.