Research Laboratory Research Articles

New Opportunities for Organic Synthesis with Superheated Flow Chemistry.

ConspectusFlow chemistry has brought a fresh breeze with great promises for chemical manufacturing, yet critical deterrents persist. To remain economically viable at production scales, flow processes demand quick reactions, which are actually not that common. Superheated flow technology stands out as a promising alternative poised to confront modern chemistry challenges. While continuous micro- and mesofluidic reactors offer uniform heating and rapid cooling across different scales, operating above solvent boiling points (i.e., operating under superheated conditions) significantly enhances reaction rates. Despite the energy costs associated with high temperatures, superheated flow chemistry aligns with sustainability goals by improving productivity (process intensification), offering solvent flexibility, and enhancing safety.However, navigating the unconventional chemical space of superheated flow chemistry can be cumbersome, particularly for neophytes. Expanding the temperature/pressure process window beyond the conventional boiling point under the atmospheric pressure limit vastly increases the optimization space. When associated with conventional trial-and-error approaches, this can become exceedingly wasteful, resource-intensive, and discouraging. Over the years, flow chemists have developed various tools to mitigate these challenges, with an increased reliance on statistical models, artificial intelligence, and experimental (kinetics, preliminary test reactions under microwave irradiation) or theoretical (quantum mechanics) a priori knowledge. Yet, the rationale for using superheated conditions has been slow to emerge, despite the growing emphasis on predictive methodologies.To fill this gap, this Account provides a concise yet comprehensive overview of superheated flow chemistry. Key concepts are illustrated with examples from our laboratory's research, as well as other relevant examples from the literature. These examples have been thoroughly studied to answer the main questions Why? At what cost? How? For what? The answers we provide will encourage educated and widespread adoption. The discussion begins with a demonstration of the various advantages arising from superheated flow chemistry. Different reactor alternatives suitable for high temperatures and pressures are then presented. Next, a clear workflow toward strategic adoption of superheated conditions is resorted either using Design of Experiments (DoE), microwave test chemistry, kinetics data, or Quantum Mechanics (QM). We provide rationalization for chemistries that are well suited for superheated conditions (e.g., additions to carbonyl functions, aromatic substitutions, as well as C-Y [Y = N, O, S, C, Br, Cl] heterolytic cleavages). Lastly, we bring the reader to a rational decision analysis toward superheated flow conditions. We believe this Account will become a reference guide for exploring extended chemical spaces, accelerating organic synthesis, and advancing molecular sciences.

Short-term solar irradiance forecasting under data transmission constraints

We report a data-parsimonious machine learning model for short-term forecasting of solar irradiance. The model follows the convolutional neural network – long-short term memory architecture. Its inputs include sky camera images that are reduced to scalar features to meet data transmission constraints. The model focuses on predicting the deviation of irradiance from the persistence of cloudiness (POC) model. Inspired by control theory, a noise signal input is used to capture the presence unknown and/or unmeasured input variables and is shown to improve model predictions, often considerably. Five years of data from the NREL Solar Radiation Research Laboratory were used to create three rolling train-validate sets and determine the best representations for time, the optimal span of input measurements, and the most impactful model input data (features). For the chosen test data, the model achieves a mean absolute error of 74.29 W/m2over a time horizon of up to two hours, compared to a baseline 134.35 W/m2 using the POC model.

Ensuring Stability of Anode Catalysts in PEMWE: From Material Design to Practical Application.

Proton Exchange Membrane Water Electrolysis (PEMWE) has emerged as a clean and effective approach for the conversion and storage of renewable electricity, particularly due to its compatibility with fluctuating photovoltaic and wind power. However, the high cost and limited performance of iridium oxide catalysts (i.e. IrO2) used as anode catalyst in industrial PEM electrolyzers remain significant obstacles to widespread application. Although numerous low-cost and efficient alternative catalysts have been developed in laboratory research, comprehensive stability studies critical for industrial use are often overlooked. This leads to the failure of performance transfer from catalysts tested in liquid half-cell systems to those employed in PEM electrolyzers. This concept presents a thorough overview for the stability issues of anode catalysts in PEMWE, and discuss their degradation mechanisms in both liquid half-cell systems and PEM electrolyzers. We summarize comprehensive protocol for the assessment and characterization, analyze the effective strategies for stability optimization, and explore the opportunities for designing viable anode catalysts for PEM electrolyzers.

Deterministic approach to assess landslide susceptibility and landslide activity in the Central-Western Region of Slovakia

Quantitative assessments in landslide susceptibility evaluation are typically dominated by statistical analyses. However, this paper employs a deterministic approach to construct such maps, specifically focusing on the stability assessment of shallow landslides with slip surfaces generally not exceeding 5 m in depth at a regional scale. The study area chosen for this research is the landslide-prone region between Hlohovec and Sereď towns in the central-western part of Slovakia. Our focus is on the activation of shallow landslides, representing the youngest, third generation of landslide evolution in the area. For the stability assessment, three scenarios were considered using deterministic analysis: a scenario involving dry slopes, a scenario under partially saturated conditions, and a scenario of fully saturated slopes. This approach enables the assessment of stability conditions based on qualitative parameters derived from both field and laboratory research. The results from the deterministic analysis aid in defining different stages of activity within the landslide body. These Landslide susceptibility maps were verified directly in the field, and most landslides reactivated from 2011 to the present fell into the class with the safety factor below 1.0. In comparison with the landslide hazard map created by using bivariate statistical analysis, it was observed that 89.97% of the area is in a very high level of landslide hazard, given a safety factor below 1.0. This highlights the effectiveness of the deterministic approach in capturing the vulnerability of the region to shallow landslides.

Confirmación del diagnóstico clínico-radiográfico de pulpitis reversible e irreversible a través del método histopatológico, en pacientes de 3 a 8 años que acuden a la UEO. Antecedentes, estado actual y prospectiva en la SEDENA

Objective: To determine if the histopathological study is associated with the clinical-radiographic diagnosis of reversible and irreversible pulpitis, in patients from 3 to 8 years of age who come to the UEO. Methodology: Conventional clinical diagnostic methods were used for the clinical-radiographic evaluation of reversible and irreversible pulpitis; Likewise, an excisional biopsy of the pulp tissue of 41 dental organs that presented pulp pathology was performed using dentin cutting spoons. In the research laboratory of the Universidad Autónoma del Estado de México (UAEM), using light microscopy, the pulp tissue was studied by a stomatologist specialist and the histopathological diagnosis of the biopsies was established. Results: The McNemar statistical test (comparison of proportions for related samples) resulted in no statistically significan difference (p>0.05, 95 % CI) between the presumptive diagnosis and the confirmatory diagnosis. Limitations: No limitations were considered. Value: An alternative method can be used in places where all means are not available. Conclusions: The histopathological diagnosis confirmed the clinical-radiographic diagnosis in this sample, so it is suggested to use all conventional diagnostic methods to establish a more accurate diagnosis and therefore a better treatment.

Purchases dominate the carbon footprint of research laboratories

Despite increasing interest for the carbon footprint of higher education institutions, little is known about the carbon footprint associated to research activities. Air travel and attendance to conferences concentrate recent data and debates but purchases have attracted little attention. Here we develop a hybrid method to estimate the greenhouse gas emissions (GHG) associated to research purchases. To do so, we combine macroeconomic databases, research-centered companies footprints and life-cycle assessments to construct a public database of monetary emission factors (EF) for research purchases. We apply it to estimate the purchases emissions of a hundred of research laboratories in France, belonging to the Labos 1point5 network and gathering more than 20000 staff, from all disciplines. We find that purchases dominate laboratory emissions, accounting for more than 50% of emissions, with a median of 2.7 t CO2e/pers, which is 3 to 4-fold the separate contribution from travel, commutes and heating. Median electricity emissions are 5-fold lower in our dataset of laboratories using low carbon electricity but they become preponderant for high carbon electricity mixes (3.5 t CO2e/pers). Purchases emissions are very heterogeneous among laboratories and are linearly correlated with budget, with an average carbon intensity of 0.31 ± 0.07 kg CO2e/€ and differences between research domains. Finally, we quantify the effect of a series of demand-driven mitigation strategies obtaining up to −20% in total emissions (−40% in purchases emissions), suggesting that effectively reducing the carbon footprint of research activities calls for systemic changes.

PGE2 Regulates the Plasminogen Activator Pathway in Human Endometrial Endothelial Cells: A New In Vitro Model to Investigate Heavy Menstrual Bleeding

To study the role of PGE2 in regulating plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) in human primary endometrial endothelial cells (HEECs) from women with normal menstrual bleeding (NMB) and heavy menstrual bleeding (HMB). In vitro study using endometrial endothelial cells. Research laboratory setting. Women with normal menstrual bleeding (NMB) and heavy menstrual bleeding (HMB) provided endometrial biopsy samples. PGE2 and PGE2 receptor-selective agonists were administered to cultured HEECs. Levels of PAI-1 and tPA in NMB-HEECs and HMB-HEECs after treatment with PGE2 and receptor-selective agonists. PGE2 increased total PAI-1 levels in NMB-HEECs, but not in HMB-HEECs, which had higher baseline PAI-1 levels. PTGER1 and PTGER2 agonists increased PAI-1 in NMB-HEECs, while PTGER3 and PTGER4 did not. PGE2 had no effect on tPA levels in either NMB-HEECs or HMB-HEECs. PGE2, through PTGER1 and PTGER2, regulates the plasminogen activator system in NMB-HEECs, suggesting a role in reducing fibrinolytic activity during normal menstrual cycles. The lack of PGE2 effect and elevated baseline PAI-1 in HMB-HEECs support using this in vitro model to further understand prostaglandin pathways in normal and heavy menstrual bleeding.

International survey on invasive lobular breast cancer identifies priority research questions

There is growing awareness of the unique etiology, biology, and clinical presentation of invasive lobular breast cancer (ILC), but additional research is needed to ensure translation of findings into management and treatment guidelines. We conducted a survey with input from breast cancer physicians, laboratory-based researchers, and patients to analyze the current understanding of ILC, and identify consensus research questions. 1774 participants from 66 countries respondents self-identified as clinicians (N = 413), researchers (N = 376), and breast cancer patients and advocates (N = 1120), with some belonging to more than one category. The majority of physicians reported being very/extremely (41%) to moderately (42%) confident in describing the differences between ILC and invasive breast cancer of no special type (NST). Knowledge of histology was seen as important (73%) and as affecting treatment decisions (51%), and most agreed that refining treatment guidelines would be valuable (76%). 85% of clinicians have never powered a clinical trial to allow subset analysis for histological subtypes, but the majority would consider it, and would participate in an ILC clinical trials consortium. The majority of laboratory researchers, reported being and very/extremely (48%) to moderately (29%) confident in describing differences between ILC and NST. They reported that ILCs are inadequately presented in large genomic data sets, and that ILC models are insufficient. The majority have adequate access to tissue or blood from patients with ILC. The majority of patients and advocates (52%) thought that their health care providers did not sufficiently explain the unique features of ILC. They identified improvement of ILC screening/early detection, and identification of better imaging tools as top research priorities. In contrast, both researchers and clinicians identified understanding of endocrine resistance and identifying novel drugs that can be tested in clinical trials as top research priority. In summary, we have gathered information from an international community of physicians, researchers, and patients/advocates that we expect will lay the foundation for a community-informed collaborative research agenda, with the goal of improving management and personalizing treatment for patients with ILC.

Endometriotic tissue fragments are viable after cryopreservation in an ex vivo tissue model recapitulating the fibrotic microenvironment.

Is it possible to establish an ex vivo endometriosis model using cryopreserved endometriotic tissue fragments? Cryopreserved endometriotic tissue fragments remain viable after thawing and during at least 3days of culture and can therefore be used to establish an ex vivo endometriosis model to efficiently test potential therapeutic agents. Endometriosis is the most prevalent benign gynecologic disease with an enormous societal burden; however, curative therapies are still lacking. To efficiently test potential new therapies, an ex vivo model based on previously cryopreserved endometriotic tissue that recapitulates the different endometriosis subtypes and their microenvironment is highly desirable. Endometriotic tissue fragments of three different subtypes were obtained from 28 patients by surgical resection. After cryopreservation and thawing, viability and metabolic activity of these tissue fragments were assessed. Viability was compared with fresh fragments from 11 patients directly after surgical removal. Experimental intervention studies were performed in cryopreserved and thawed tissue fragments from two patients to confirm the usability of these tissues for ex vivo intervention studies. Endometriotic tissue fragments (n = 45) were cryopreserved according to three different protocols. After thawing, fragments were cultured for 24 h. A resazurin-based assay was performed to assess the metabolic activity of the tissue fragments. In addition, cell type-specific viability was analyzed by VivaFix, Hoechst 33342, and α-smooth muscle actin immunofluorescence staining and confocal microscopy. The presence of endometriosis was histologically confirmed based on hematoxylin-eosin staining. Cryopreserved and thawed tissue fragments were treated for 72 h with pirfenidone or metformin and COL1A1 and CEMIP gene expressions were assessed using RT-PCR and RT-qPCR, either in the whole tissue fragments or in myofibroblasts isolated by laser capture microdissection. Metabolic activity of endometriotic tissue fragments obtained from peritoneal (PER), ovarian (OMA), and deep (DE) endometriotic lesions was well preserved after cryopreservation in a dimethyl sulfoxide-based medium and was comparable with fresh tissue fragments. Relative metabolic activity compared to fresh tissue was 70% (CI: 92-47%) in PER, 43% (CI: 53-15%) in OMA and 94% (CI: 186-3%) in DE lesions. In fragments from PE lesions 92% (CI: 87-96%), from OMA lesions 95% (CI: 91-98%), and from DE lesions 88% (CI: 78-98%) of cells were viable after cryopreservation and thawing followed by a 24-h culture period. Differences in gene expression of fibrotic markers COL1A1 and CEMIP after 72-h treatment with pirfenidone or metformin could be detected in whole tissue fragments and in isolated myofibroblasts, indicating that cryopreserved and thawed endometriotic tissue fragments are suitable for testing anti-fibrotic interventions. N/A. Viability and metabolic activity of the endometriotic tissue fragments may have been partially compromised by damage sustained during the surgical procedure, contributing to inter-sample variance. The storage of viable endometriotic tissue fragments for later usage in an ex vivo model creates the possibility to efficiently test potential new therapeutic strategies and facilitates the exchange of viable endometriotic tissue between different research laboratories. This study was not financially supported by external funding. The authors declare no competing interest. N/A.

Maximal productivity rate of threading machine operations

The quality of products in manufacturing engineering depends first of all on the machining processes. One of the crucial economic components of the production processes is the metal-cutting machining technologies that form the quality of manufactured objects. The physics of metal-cutting technologies is complex and cannot be described by one mathematical model because of different natures. Researchers derived an empirical formula of their tool life that describes the properties of the metal-cutting tools depending on many mechanical factors mentioned above. Engineers investigated and worked the metal-cutting regimes for manufacturing processes that comprise recommendations for the tool life. The components of the tool life are obtained by the practical tests at the research laboratories that give the approximated results. Practice shows the recommendations of the handbooks for metal-cutting regimes are not always optimal for manufacturing processes. The machine tools’ work in the manufacturing environment differs from the research laboratories. This work considers the analytical optimization of the cutting speed for the threading machine tool by the criterion of its maximal productivity rate.

Mechanical release of homogenous proteins from supramolecular gels

A long-standing challenge is how to formulate proteins and vaccines to retain function during storage and transport and to remove the burdens of cold-chain management. Any solution must be practical to use, with the protein being released or applied using clinically relevant triggers. Advanced biologic therapies are distributed cold, using substantial energy, limiting equitable distribution in low-resource countries and placing responsibility on the user for correct storage and handling. Cold-chain management is the best solution at present for protein transport but requires substantial infrastructure and energy. For example, in research laboratories, a single freezer at −80 °C consumes as much energy per day as a small household1. Of biological (protein or cell) therapies and all vaccines, 75% require cold-chain management; the cost of cold-chain management in clinical trials has increased by about 20% since 2015, reflecting this complexity. Bespoke formulations and excipients are now required, with trehalose2, sucrose or polymers3 widely used, which stabilize proteins by replacing surface water molecules and thereby make denaturation thermodynamically less likely; this has enabled both freeze-dried proteins and frozen proteins. For example, the human papilloma virus vaccine requires aluminium salt adjuvants to function, but these render it unstable against freeze–thaw4, leading to a very complex and expensive supply chain. Other ideas involve ensilication5 and chemical modification of proteins6. In short, protein stabilization is a challenge with no universal solution7,8. Here we designed a stiff hydrogel that stabilizes proteins against thermal denaturation even at 50 °C, and that can, unlike present technologies, deliver pure, excipient-free protein by mechanically releasing it from a syringe. Macromolecules can be loaded at up to 10 wt% without affecting the mechanism of release. This unique stabilization and excipient-free release synergy offers a practical, scalable and versatile solution to enable the low-cost, cold-chain-free and equitable delivery of therapies worldwide.

Long-Term Culture of Human Pluripotent Stem Cells in Xeno-Free Condition Using Functional Polymer Films.

Human pluripotent stem cells (hPSCs), encompassing human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), hold immense potential in regenerative medicine, offering new opportunities for personalized cell therapies. However, their clinical translation is hindered by the inevitable reliance on xenogeneic components in culture environments. This study addresses this challenge by engineering a fully synthetic, xeno-free culture substrate, whose surface composition is tailored systematically for xeno-free culture of hPSCs. A functional polymer surface, pGC2 (poly(glycidyl methacrylate-grafting-guanidine-co-carboxylic acrylate)), offers excellent cell-adhesive properties as well as non-cytotoxicity, enabling robust hESCs and hiPSCs growth while presenting cost-competitiveness and scalability over Matrigel. This investigation includes comprehensive evaluations of pGC2 across diverse experimental conditions, demonstrating its wide adaptability with various pluripotent stem cell lines, culture media, and substrates. Crucially, pGC2 supports long-term hESCs and hiPSCs expansion, up to ten passages without compromising their stemness and pluripotency. Notably, this study is the first to confirm an identical proteomic profile after ten passages of xeno-free cultivation of hiPSCs on a polymeric substrate compared to Matrigel. The innovative substrate bridges the gap between laboratory research and clinical translation, offering a new promising avenue for advancing stem cell-based therapies.

DETERMINATION OF POLYPHENOLIC COMPOUNDS IN PHYTOEXTRACTS WITH ANTIBACTERIAL PROPERTIES AND STUDY POTENTIAL EFFECTS

Objectives. The research work is a comparative study of the polyphenolic compounds and flavonoid content of the phytoextracts obtained from the ultrasonic extraction process (Stegler DG-360) with 95% ethanol and ethanol-propyleneglycol mixture (in 95 : 5 ratio) from the Clove buds (Caryophyllos aromaticus L. Myrtaceae), hibiscus flowers (Hibiscus sabdariffa L. (Hs, roselle; Malvaceae)) and common yarrow (Achillea millefolium L. Asteraceae) plants, which are rich in biologically active substances with high therapeutic effect, as well as their devoted to the investigation of antioxydant activity and antimicrobial potential. Material and methods. The research work was carried out in the Central Research and Application Laboratory of Ağrı İbrahim Çeçen University (MERLAB), Republic of Turkey, using a Japanese Shimadzu brand Mistral-AB SCIEX 4000 QTRAP liquid chromatograph-mass spectrometer device. Results.It was found that in both extraction processes, the active substances penetrated sufficiently from the medicinal-plant raw materials into the extractant. 20 names of compounds containing polyphenol, flavonoid and anthocyanin derivatives have been determined. However, the amount of active substances in the phytoextract obtained with the presence of the penetrate (propylene glycol) was higher. In particular, rutin ( 75.74 ± 4.91mg/g), quercetin (110.12 ± 1.30 mg/g), gallic acid (4503.19 ± 46.83mg/g), quinic acid (4041.99 ± 187.3 mg/g), chlorogenic acid (582.30 ± 1.30mg/g), vanilin (155.6g/g1 ± 3.95mg/g) prevailed. Conclusion. The research work proves once again that the studied phytoextracts are rich in polyphenolic compounds and flavonoids. The amount of biologically active substances in the phytoextract obtained with the ethanol-propylene glycol mixture which is the penetrate substance (in the ratio of 95:5) is higher than that of the other sample (with 95% ethanol). The resulting amount of biologically active substances is a clear proof that the phytoextract has sufficient antioxidant and antimicrobial properties.

(Mis)alignments between postdoctoral and supervisors' perceptions of mentorship competencies in engineering and computer science

AbstractBackgroundPostdoctoral training holds an increasingly important place in preparation for leading academic and research positions. While little empirical research has described postdoctoral training beyond the sciences, across all fields, “misaligned expectations” are often touted as a key source of postdoctoral strife.Purpose/HypothesisThis article describes mentorship competency beliefs within engineering and computer science fields, which increasingly engage in postdoctoral training.Design/MethodAn embedded mixed‐methods design was used to quantitatively identify mentorship profiles from survey data using latent profile analysis (LPA) from a sample of n = 118 postdoctoral scholars and n = 165 postdoctoral supervisors. Qualitative thematic analysis of interviews with n = 29 postdoctoral scholars and n = 20 postdoctoral supervisors was used to identify meaning in the differences between quantitative profiles. The combination of LPA with thematic analysis enabled the triangulation of distinct postdoctoral mentorship profile definitions.ResultsLPA identified six postdoctoral fellow profiles and four supervisor profiles, which became clearly definable through thematic analysis. Postdoc profiles included Technical Manager, Autonomy Focused Advisor, Stretched Mentor, Well‐Rounded Mentor, Exemplar Mentor, and Leader‐Mentor, while supervisor profiles included Autonomous Mentor, Reflective Mentor, Research Lab Mentor, and Confident Leader‐Mentor. Some of these are aligned, but several are not, giving insight into the phenomenon of “misaligned expectations” in postdoctoral literature.ConclusionsThe mentorship profiles illustrate the misalignment in expectations, which leads to negative mentorship experiences for many postdoctoral scholars.

Principal test for color sensation: clinical aspects.

Visual function comprises three principles: light sensation, color sensation, and minimum separable sensation. Although clinical evaluation of light sensation and visual acuity have been remarkably developed through comprehensive application of various methods, the test methods to evaluate color sensation in the clinical field have not reflected these various significant developments after their recommendation at the International Congress of Ophthalmology in 1933. To date, various research methods in color vision have been invented on the basis of clinical evaluation methods, most of which were limited to laboratory investigations and were not applied to the clinical field. In this review, the author focuses on both the currently clinical available evaluation methods and the clinically applicable methods based on the present laboratory research studies.

GINA-2024: Key Modifications and Strategic Implementations for Targeted Therapeutic Interventions

This article provides a succinct overview of the revisions and augmentations incorporated into the 2024 edition of GINA (Global Initiative for Asthma). A comparative analysis is conducted between the diagnostic and therapeutic algorithms for bronchial asthma (BA) in children outlined in the updated GINA guidelines and those delineated in the Kyrgyz clinical protocol on BA issued in 2023. Leveraging the latest iteration of GINA, a series of organizational, scientific, clinical, and diagnostic initiatives are slated for implementation in Kyrgyz Republic. Notably, on the basis of the department of allergology and clinical immunology of the National center for maternity and childhood care under the Ministry of health of the Kyrgyz Republic, a research laboratory on allergology, including a room for genetically engineered biological therapy, will be created.

Analytical advances in horseracing medication and doping control from 2018 to 2023.

The analytical approaches taken by laboratories to implement robust and efficient regulation of horseracing medication and doping control are complex and constantly evolving. Each laboratory's approach will be dictated by differences in regulatory, economic and scientific drivers specific to their local environment. However, in general, laboratories will all be undertaking developments and improvements to their screening strategies in order to meet new and emerging threats as well as provide improved service to their customers. In this paper, the published analytical advances in horseracing medication and doping control since the 22nd International Conference of Racing Analysts and Veterinarians will be reviewed. Due to the unprecedented impact of COVID-19 on the worldwide economy, the normal 2-year period of this review was extended to over 5years. As such, there was considerable ground to cover, resulting in an increase in the number of relevant publications included from 107 to 307. Major trends in publications will be summarised and possible future directions highlighted. This will cover developments in the detection of 'small' and 'large' molecule drugs, sample preparation procedures and the use of alternative matrices, instrumental advances/applications, drug metabolism and pharmacokinetics, the detection and prevalence of 'endogenous' compounds and biomarker and OMICs approaches. Particular emphasis will be given to research into the potential threat of gene doping, which is a significant area of new and continued research for many laboratories. Furthermore, developments in analytical instrumentation relevant to equine medication and doping control will be discussed.

The effects of verbal cues on EMG activity during a quadriceps setting exercise.

A quadriceps setting (quad set) exercise is commonly utilized following knee injury, but there is great variation in cues that clinicians provide to patients when performing the exercise. To determine if internal, external, or visual cues results in the greatest quadriceps electromyographical (EMG) activity during a quadriceps setting exercise in healthy individuals. Descriptive laboratory study. University research laboratory. Thirty healthy individuals volunteered for this study. Participants were given one of five cues in a randomized order: internal cue "tighten your thigh muscles," internal cue "push your knee down," external cue "push into the bolster," external cue "push into the strap," or visual biofeedback using the cue "raise the value on the screen as high as you can." Normalized vastus lateralis EMG activity. Both visual biofeedback (83.2±24.9%) and "press into the strap" (76.8±24.4%) produced significantly greater (p< 0.001) EMG activity than the push knee down (53.2±27.0%), tighten thigh (52.7±27.3%), or push into the bolster (50.8±26.3) conditions. There was no significant difference (p= 0.10) between the visual biofeedback and "press into the strap" conditions as well as no significant difference (p> 0.38) between the push knee down, tighten thigh, or push into the bolster conditions. If the clinical aim during a quadriceps setting exercise is to obtain the greatest volitional muscle recruitment, the use of visual biofeedback or pressing into a strap is recommended.

Surveillance of PFAS in sludge and biosolids at 12 water resource recovery facilities.

Per- and polyfluoroalkyl substances (PFAS) are refractory anthropogenic chemicals and current treatment processes at municipal water resource recovery facilities (WRRFs) cannot efficiently degrade them, hence, these chemicals cycle through the environment. Certain PFAS can be concentrated in biosolids from WRRFs and are commonly land applied for beneficial reuse. Given recent advances in measurement of PFAS, documentation of the range of concentrations in pre-stabilized sludge and stabilized biosolids is critical to evaluating treatment best practices and assessing potential human health and ecological risks. In this study, pre-stabilized sludge and post-stabilized biosolids samples were collected from 12 major WRRFs across the United States. PFAS were analyzed using Environmental Protection Agency (EPA) Method SW846-3500C/537.1, and Draft EPA Method 1633, by one commercial laboratory and two university research laboratories, respectively. Results comparison among laboratories demonstrated statistical differences in PFAS concentrations among split samples. For example, 5:3 FTCA (fluorotelomer carboxylic acid) concentrations in post-stabilized sludge at Lab 1 were measured at 21ng/g (dry), while they were detected at 151ng/g (dry) in Lab 3. Further, higher PFAS concentrations were observed in post-stabilized biosolids compared to pre-stabilized sludges, regardless of the laboratory or analysis method, even when solids destruction through solids stabilization was considered. Further research is required to refine methods for analyses of PFAS in sludge and biosolids samples from WRRFs prior to being used for development of regulatory actions as well as understanding how various treatment protocols could impact concentrations of PFAS in land-applied biosolids.

Reference Intervals of Mass Coefficients and Absolute Weights of Mini Pigs’ Organs

Introduction. Measurement of weights and calculation of mass coefficients of the laboratory animals’ internal organs are the integral stages of toxicological research. However, the absence of the correct intra-laboratory reference intervals corresponding to the normal values established for the animal population of a research laboratory could hinder the analysis of the mass coefficient changes in the experiment. For example, the data on weights and mass coefficients of mini pigs’ organs is being an issue due to its insufficient availability in the open sources. At the same time, in the literature there is a lot of such kind of data referring to the industrial pig breeds. Due to the wide use of the mini pigs in the pre-clinical research and because in the pig species taxonomy they are considered to be a weight category representing the pigs with reduced mass of the body with similar morphology of the organs and body systems, we have set an objective to determine and calculate the reference intervals of mass coefficients of internal organs relative to the mass of the body and brain, as well as the absolute weights of mini pigs’ internal organs and compare the results with the data on mini and industrial pig breeds in the literature sources.Materials and Methods. The data on 29 males and 29 females of the Vietnamese lop-bellied mini pig breed aged 6 months and older, who used to be in control groups of the various experiments held at JSC “SPA “House of Pharmacy” (Leningrad region) in the period from January 2018 to March 2024, was used to calculate the reference intervals. The statistical analysis was peRussian Federationormed using Microsoft Excel and Reference Value Advisor v2.1 software in compliance with the CLSI guidelines. Calculation of the reference intervals for all parameters was carried out by a robust method, the compliance with the normal distribution law was determined by Anderson–Darling test, in case of abnormal distribution of data, calculation of the reference interval was carried out with the Box–Cox transformation.Results. The data on the absolute weights of organs and their coefficients relative to the body and brain masses were presented in the form of the lower and upper reference limits and confidence intervals for each of the limit. The reference intervals of masses of organs across all parameters in males and females had similar limits, the most comparable values were found for the heart and brain parameters. The calculated interval of the heart absolute weight in males was 28.3–253 g, that of the brain was 46.5–93.7 g; in females these intervals were 42.9–279 g and 55.5–81.8 g respectively. Upon comparing the obtained data with the literature sources, it was found that the majority of the absolute weights of all measured mini pigs’ organs had fitted in the limits of the reference values, whereas the masses of the lungs and liver were at the lower limit or below the calculated intervals. The values of the absolute weights of most of the organs of the industrial pig breeds were higher than that of mini pigs, which was due to the difference in the body size and mass of the studied animal breeds. When comparing the mass coefficients of organs in relation to the body mass, it was found that the coefficients of most organs of the industrial breeds and mini pigs, on the contrary, were within the calculated reference intervals or slightly exceeded them.Discussion and conclusion. The calculated reference intervals of the mass coefficients of some organs in relation to the body mass, as well as the absolute weights of the spleen in mini pigs are comparable with the data available in literature for the industrial meat pig breeds. At the same time, the data available in the literature sources on the absolute weights of organs and their mass coefficients relative to the body mass of mini pigs, in most cases, have fitted into the calculated intervals. To increase the prognostic value of the obtained reference intervals, the analysis of a larger size sample is necessary.