Comparison Of Profiles Research Articles

Cross-species imputation and comparison of single-cell transcriptomic profiles.

Cross-species comparison and prediction of gene expression profiles are important to understand regulatory changes during evolution and to transfer knowledge learned from model organisms to humans. Single-cell RNA-seq (scRNA-seq) profiles enable us to capture gene expression profiles with respect to variations among individual cells; however, cross-species comparison of scRNA-seq profiles is challenging because of data sparsity, batch effects, and the lack of one-to-one cell matching across species. Moreover, single-cell profiles are challenging to obtain in certain biological contexts, limiting the scope of hypothesis generation. Here we developed Icebear, a neural network framework that decomposes single-cell measurements into factors representing cell identity, species, and batch factors. Icebear enables accurate prediction of single-cell gene expression profiles across species, thereby providing high-resolution cell type and disease profiles in under-characterized contexts. Icebear also facilitates direct cross-species comparison of single-cell expression profiles for conserved genes that are located on the X chromosome in eutherian mammals but on autosomes in chicken. This comparison, for the first time, revealed evolutionary and diverse adaptations of X-chromosome upregulation in mammals.

Comparative DNA profiling of conceptus parts in paternity disputes and rape investigations: a case study

Forensic laboratories frequently receive cases related to abortion, particularly in the context of paternity disputes and rape crimes. However, the focus has traditionally been on the foetus, while the placenta and its associated components, which start development after one month and mature within three months, are often overlooked. This study represents the comparison of DNA profiling from various parts of the aborted conceptus, including the placenta (foetal side), placenta (maternal side), umbilical cord, and foetus. The results have produced consistent and expected profiles but with meticulous foetal tissue processing. Due to the significant presence of maternal blood in these components, a rigorous washing procedure for the aborted foetal material is imperative before DNA extraction can be carried out. The generated profiles emphasize the equal forensic utility of different conceptus components, challenging the conventional focus on the foetus alone. This study paves the way for collecting and processing of various developed parts of the conceptus for DNA profiling as required by the specific case scenarios.

Exploring flavor perception through metabolite profiling and sensory approaches during starter kimchi fermentation

Starter cultures can enhance sensory properties during the starter kimchi fermentation. However, while many studies have primarily focused on physicochemical properties, the impact of starters on flavor perception remains unclear. The aim of this study was to assess the impact of starter culture inoculation, specifically Companilactobacillus allii WiKim39 and Lactococcus lactis WiKim0124, on aroma and flavor perception through a comparison of metabolite profiling and electronic tongue and nose data. Notably, 19 and 11 compounds were identified using UHPLC-Q-Orbitrap-MS and HPLC, respectively. Principal component analysis revealed that variations in fermentation metabolites and sensory properties were significantly categorized based on the particular starter culture employed during the ripening process. Moreover, the correlation analysis between the 19 key fermentative metabolites and e-tongue measurements in each starter kimchi revealed significant differences in sourness (AHS), bitterness (SCS), and comprehensive taste (CPS and PKS) sensors. The e-nose system identified four major volatile compounds contributing to the sweetness and off-flavor-related aroma profile of the starter kimchi. These findings highlight the significant impact that starter culture has on taste and flavor development, serving as a valuable guide in predicting sensory properties during starter kimchi fermentation.

Comparison of genomic profiling of patient-matched primary colorectal and surgical resected distant metastatic (stage IV) colorectal carcinoma for drug actionability

It is often difficult to obtain adequate tissue for genomic study from distant metastases for assessment of targeted therapy in colorectal carcinomas. The study aims to explore the genomic differences between matched distant metastatic colorectal carcinomas (mCRC) and primary carcinoma using surgical specimens of both with adequate tissue. Thirty-four paired primary and distant metastatic colorectal carcinoma samples (liver, ovary, and lung) were obtained from surgical excisions (not small biopsies) and are microsatellite stable. They were subjected to DNA sequencing using comprehensive next-generation sequencing. This included mutation concordance analysis and mutational signature analysis. The mutation concordance analysis showed 49.6% shared mutations between primary and metastatic tumours, with 23.0% mutations exclusive to primary tumours and 27.4% mutations exclusive to distant metastases. While many patients with KRAS/BRAF mutations had shared mutations, two cases had unique KRAS mutations in the primary tumours only. Additionally, TMB (tumour mutational burden) analysis revealed that half of the TMB-high (≥7.5 mutations/Mb) metastatic colorectal carcinomas had a low TMB (<7.5 mutations/Mb) in the primary tumours. The mutational signature analysis identified de novo signatures consistent with known single base substitution patterns such as SBS11 (alkylation agents) and SBS30 (base excision repair deficiency) post-chemotherapy. To conclude, this study demonstrates significant genomic variations in resected distant metastasis when compared to primary colorectal carcinomas when adequate tissue is available. This finding underscores the importance of considering these differences and selecting tissue for mutation analysis in planning targeted and effective treatment strategies for mCRC.

Genetic and Immunological Characterization of Brain Metastases from Solid Cancers.

Brain metastasis, a leading cause of cancer death, is a clinical challenge. Recently, genetic characterization of brain metastatic lesions based on next generation sequencing-based advanced technologies, such as single-cell RNA sequencing, has been performed to develop novel efficient therapies. The present study aimed to investigate brain-metastasis-specific biomarkers as well as relevant prognostic factors. The genetic profiles and expression levels of immune response-associated genes and 820 cancer-associated genes were compared between primary cancer lesions and metastatic cancer lesions obtained from nine cancer patients at the Shizuoka Cancer Center. Cytokine and chemokine marker genes were analyzed via quantitative PCR. T-cell receptor (TCR) repertoire profiling was performed for the same patients. For survival analysis, survival data of 52 cancer patients with brain metastases were utilized. Comparison of driver mutation profiling between primary and metastatic lesions revealed shared core mutations in both lesions and a few new mutations in metastatic lesions. A high tumor mutation burden (TMB) was detected in metastatic lesions. Volcano plot analysis revealed specific features of the metastatic tumor microenvironment, such as cancer signaling promotion and immune suppression due to decreased immune cell infiltration. Survival analysis revealed that three genes, the TREML2 gene, the BTLA gene on activated microglia and the CERS2 gene on metastatic tumor, were potent prognostic factors. High TMB in metastatic lesions indicates potential benefit from immune checkpoint inhibitor usage for brain metastasis and TREML2 and BTLA are factors associated with poor prognosis. Activated microglia may be novel targets for the treatment of brain metastasis.

Application of bootstrap f2 to dissolution data from biorelevant media and evidence of the conservative nature of bootstrap f2

f2 with or without bootstrapping is the most common method to compare in vitro dissolution profiles, but methods to compare dissolution profiles have become less harmonized. The objective was to compare outcomes from bootstrap f2 and f2 (i.e. not-bootstrapped f2) using a large set of in vitro dissolution data. Non-parametric bootstrapping was performed on the 104 profile comparisons that did not meet the percent coefficient of variation (CV%) criteria to use average dissolution data. Bootstrap f2 was taken as the lower 90 % confidence interval of bootstrapped samples. There was concordance between bootstrap f2 and f2 in 92 of the 104 comparisons (88 %). There were no false positives. However, 12 % were false negative. Inspection of these discordance pairs suggests that bootstrap f2 serves as a conservative approach to assess profile similarity, particularly when a value of 50 is being used as decision criteria.

Comparison of the gene expression profile of testicular tissue before and after sexual maturity in Qianbei Ma goats

BackgroundWith long-term research on the reproductive ability of Qianbei Ma goat, we found that the puberty of the male goats comes at the age of 3 months and reaches sexual maturity at 4 months,the male goats are identified as physically mature at 9 months and able to mate. Compared with other kinds of breeds of goats, Qianbei Ma goat is featured with more faster growth and earlier sexual maturity.Therefore, in order to explore the laws of growth of Qianbei Ma goat before sexual maturity(3-month-old)and after sexual maturity (9-month-old). The testicular tissue was collected to explore their changes in morphology through HE staining, the serum was collected to detect the hormone content, and the mRNA expression profile of the testis was analyzed by transcriptomics. In this way, the effect of testicular development on the reproduction of Qianbei ma goats was further analyzed.ResultsThe results showed that the area and diameter of spermatogenic tubules were larger at 9 months than 3 months, and the number of spermatocytes, interstitial cells, spermatogonia and secondary spermatocytes in the lumen of the tubules showed a similar trend. The appearance of spermatozoa at age 3 months indicated that puberty had begun in Qianbei Ma goats. The Elasa test for testosterone, luteinizing hormone, follicle stimulating hormone and anti-Müllerian hormone showed that the levels of these hormones in the serum at age 9 months were all highly significantly different than those at age 3 months (P < 0.01). There were 490 differentially expressed genes (DEGs) between the (|log2(fold change)| > 1 and p value < 0.05) 3-month-old and 9-month-old groups, of which 233 genes were upregulated and 257 genes were downregulated (3 months of age was used as the control group and 9 months of age was used as the experimental group). According to the GO and KEGG enrichment analyses of DEGs, PRSS58, ECM1, WFDC8 and LHCGR are involved in testicular development and androgen secretion, which contribute to the sexual maturation of Qianbei Ma goats.ConclusionsPotential biomarker genes and relevant pathways involved in the regulation of testicular development and spermatogenesis in Qianbei Ma goats were identified, providing a theoretical basis and data support for later studies on the influence of testicular development and spermatogenesis before and after sexual maturity in Qianbei Ma goats.

Comparison of Efficacy and Safety Profile of Conservative Versus Surgical Management of Meniscal Injuries

Background: Surgical management of meniscal tear carries financial implications in resource limited settings like ours. Conservative management could address this issue, if its safety and efficacy profile is better understood. Objectives: The objective of this study was to compare the efficacy and safety of conservative and surgical management of patients with meniscal tear with conservative management.Material and Methods: Descriptive comparative study of 80 patients with meniscal tear, recruited through non-probability convenient sampling technique, was carried out at Orthopedic unit MMC MTI Mardan, during 1st August 2022 and 31st July 2023. Patients were assigned to surgical and conservative group. International Knee Documentation Committee (IKDC) score at baseline and 3 months after treatment were compared for efficacy. Treatment related complications were noted.Results: A total of 80 patients were enrolled with 40 patients in each group (surgical versus conservative). The mean baseline and IKDC score at week 12 in surgical versus conservative group were 45.069±13.301 versus 51.873±17.90 and 79.52±7.40 versus 73.92±11.67 respectively. Surgical group showed treatment response in 37 patients (92.5%) versus 31 (77.5%) in conservative approach (p value 0.060). Surgical site infection was observed in 5 patients (12.5%) in surgical group. Medication related adverse effects were observed in 3 patients (7.5%) in conservative group.Conclusion: No appreciable differences in the clinical results, such as pain reduction or better knee function, between patients who received meniscal surgery and those who underwent conservative treatment for meniscal tears.Keywords: Conservative Approach, Meniscal Injury, Surgical Approach, Treatment Outcomes

Numerical Study of a Thermal Plume Developing in a Neutral Environment and in Interaction: Application to Fires Problems

This study focuses on the mathematical and numerical modelling of how different properties, such as channel length and hot source height, affect the flow of thermal plumes and their interaction with the surrounding environment. Studying the behaviour of a directed thermal plume flow can provide a good visualisation of the control parameters for various applications related to fires and pollutants. To determine the control parameters affecting this flow, it is imperative to initially analyse the flow through a natural convection consisting of a disc-shaped heat source at the inlet of a vertical cylinder using mathematical and numerical methods. The flow in this study is characterised by natural convection, turbulent, steady, two-dimensional and incompressible. Numerical results were obtained via computational fluid dynamics analysis, which is based on mathematical flow modelling using the system of Navier–Stokes equations and the finite volume method. The SIMPLE algorithm was used for the velocity–pressure coupling. After introducing the concept of Reynolds averaging and analysis, different RANS turbulence models are presented, particularly two-equation models, using the Ansys Fluent software. Comparison of the different profiles revealed the ideal flow control parameters. An improvement in thermal properties was observed when the height of the heat source was = 1.5 cm and the vertical length of the channel was D = 20cm.

A Comparison of Spatial and Phenotypic Immune Profiles of Pancreatic Ductal Adenocarcinoma and Its Precursor Lesions.

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a 5-year survival rate of 12.5%. PDAC predominantly arises from non-cystic pancreatic intraepithelial neoplasia (PanIN) and cystic intraductal papillary mucinous neoplasm (IPMN). We used multiplex immunofluorescence and computational imaging technology to characterize, map, and compare the immune microenvironments (IMEs) of PDAC and its precursor lesions. We demonstrate that the IME of IPMN was abundantly infiltrated with CD8+ T cells and PD-L1-positive antigen-presenting cells (APCs), whereas the IME of PanIN contained fewer CD8+ T cells and fewer PD-L1-positive APCs but elevated numbers of immunosuppressive regulatory T cells (Tregs). Thus, immunosuppression in IPMN and PanIN seems to be mediated by different mechanisms. While immunosuppression in IPMN is facilitated by PD-L1 expression on APCs, Tregs seem to play a key role in PanIN. Our findings suggest potential immunotherapeutic interventions for high-risk precursor lesions, namely, targeting PD-1/PD-L1 in IPMN and CTLA-4-positive Tregs in PanIN to restore immunosurveillance and prevent progression to cancer. Tregs accumulate with malignant transformation, as observed in PDAC, and to a lesser extent in IPMN-associated PDAC (IAPA). High numbers of Tregs in the microenvironment of PDAC went along with a markedly decreased interaction between CD8+ T cells and cancerous epithelial cells (ECs), highlighting the importance of Tregs as key players in immunosuppression in PDAC. We found evidence that a defect in antigen presentation, further aggravated by PD-L1 expression on APC, may contribute to immunosuppression in IAPA, suggesting a role for PD-L1/PD-1 immune checkpoint inhibitors in the treatment of IAPA.

Effectiveness of enterovirus A71 vaccine against pediatric HFMD and disease profile of post-vaccination infection

BackgroundVaccination has been proven effective against infection with enterovirus A71 (EV-A71) in clinical trials, but vaccine effectiveness in real-world situations remains incompletely understood. Furthermore, it is not clear whether previous vaccination will result in symptom attenuation among post-vaccinated cases. MethodsBased on long-term data extracted from the only designed referral hospital for infectious diseases, we used a test-negative case-control design and multivariate logistic regression models to analyze the effectiveness of EV-A71 vaccine against hand, foot and mouth disease (HFMD). And then, generalized linear regression models were used to evaluate the associations between prior vaccination and disease profiles. ResultsWe selected 4883 inpatients for vaccine efficacy estimations and 2188 inpatients for disease profile comparisons. Vaccine effectiveness against EV-A71-induced HFMD for complete vaccination was 63.4 % and 51.7 % for partial vaccination. The vaccine effectiveness was higher among cases received the first dose within 12 months. No protection was observed against coxsackievirus (CV) A6-, CV-A10- or CV-A16-associated HFMD among children regardless of vaccination status. Completely vaccinated cases had shorter hospital stay and disease course compared to unvaccinated cases (P < 0.05). ConclusionsThese findings reiterate the need to continue the development of a multivalent vaccine or combined vaccines, and have implications for introducing optimized vaccination strategies.

FORMULATION AND EVALUATION OF ORODISPERSIBLE TABLET OF PROCHLORPERAZINE MALEATE

In the present work, fast disintegrating tablets of prochlorperazine maleate were designed with a view to enhance patient compliance by effervescent method. Prochlorperazine Maleate, a potent antipsychotic medication with antiemetic properties, holds significance in treating various conditions such as nausea, vomiting, and vertigo. The decision to formulate it into orodispersible tablets aimed to address issues related to patient compliance and convenience, particularly for individuals who experience difficulty swallowing conventional tablets. Formulation F10, enriched with 10% Croscarmellose sodium as a superdisintegrant and an effervescent mixture for taste masking, exhibited remarkable characteristics. Croscarmellose sodium, chosen for its exceptional disintegration properties, ensures rapid breakdown upon contact with saliva, facilitating swift drug release and subsequent onset of action. Moreover, the incorporation of an effervescent mixture not only aids in masking the potentially unpleasant taste of Prochlorperazine Maleate but also holds the potential to enhance palatability and overall patient acceptance. Physicochemical characterization of Prochlorperazine Maleate unveiled favorable attributes, including a loss on drying of 0.413±0.002%, a melting point range of 234-236°C, and a moisture content of 0.0354%, affirming its suitability for formulation into orodispersible tablets. Through dissolution profile comparisons, formulation F10 demonstrated superior drug release kinetics compared to the commercial formulation, underscoring its potential therapeutic advantages.

Comparison of solubility profiles for pioneer and generic monensin premixes in biorelevant simulated intestinal fluid based on shake flask extractions.

In the United States, a generic Type A medicated article product can gain the FDA approval by demonstrating bioequivalence (BE) to the pioneer product by successfully conducting a blood level, pharmacodynamic, or clinical BE study. A biowaiver can be granted based on several criteria, assuming the dissolution of the test and reference products represents the only factor influencing the relative bioavailability of both products. Monensin is practically insoluble in H2O per the USP definition. Previously published data from a comparison study of monensin dissolution profiles from the pioneer product and four generic products using biorelevant media showed that generic monensin products demonstrated different dissolution profiles to the pioneer product in these USP biorelevant rumen media. This follow-up study compared the solubility profiles in simulated intestinal fluid (cFaSSIF, pH 7.5) for the pioneer product and four generic products. The generic monensin products demonstrated different invitro dissolution profiles to the pioneer product in biorelevant media. The differences demonstrated in solubility and dissolution profiles are of concern regarding the potential efficacy of generic monensin in cattle. There are also additional concerns for the potential development of Eimeria resistance in cattle receiving a sub-therapeutic dose of monensin from a less soluble generic product.

Comparison of gut microbiota profiles between patients suffering from elderly frailty syndrome and non-frail elderly individuals.

Frailty syndrome is a state of increased vulnerability to stressors, marked by lowered physical strength and increased dependence on others. The well-established changes in gut microbiota associated with old age suggest a probable relationship between gut microbiota and frailty. This study was aimed at finding the relationship between gut microbiota and frailty syndrome, by comparing the sociodemographic data and the gut microbiota profiles of 23 non-frail and 14 frail elderly individuals. We used the quantitative polymerase chain reaction method (qPCR) to determine the bacterial loads of Bifidobacteria, Lactobacillus, Bacteroidetes, Prevotella, and Escherichia coli in stool samples from test subjects. We discovered a significant increase in the bacterial load of Prevotella in frail elderly individuals aged 70 or above. Other bacterial loads and ratios were not significantly different between the two groups. More comprehensive studies with larger sample sizes and encompassing a wider range of inflammation-related bacteria need to be performed to discover the existence and exact nature of these relations.

Early Holocene vegetation development at Mesolithic fen dwelling sites in Dagsmosse, south-central Sweden, and its implications for understanding environment–human dynamics at various scales

Recent discoveries of several Mesolithic sites within the Dagsmosse Basin, south-central Sweden, offer an opportunity to study the lifestyle and skillsets of Mesolithic hunter-gatherer-fishers operating in wetland environments. In this paper, we present a combined archaeological and palaeoecological analysis of a Mesolithic fenland environment using Repetitive-Proxy Pollen Analysis (RPPA) of early Holocene sequences. Based on comparison of stratigraphic profiles from two cores within the basin, we infer that the variance in pollen composition and anthropogenic signals reflect variability in human/vegetation interactions in the fenland, at different distances to the main human dwelling at Jussberg (9.0–8.2 ka cal BP). Our study describes the socio-environmental relations within the wetland and adjacent terrestrial areas, providing a basis for tracking changes in forager interactions with their surroundings during the Mesolithic. Pollen analysis is consistent with the previously established sequence of settlement phases and extent as well as providing new data concerning the anthropogenic impacts on plant communities within the wetland including the use, reuse, and management of vegetation taxa. Correlations between palaeoecological and archaeological data demonstrate that forager communities (i) prevailed in the open fenland landscape between 9.3 and 8.2 ka cal BP, (ii) actively altered taxa composition through small-scale clearings of pine (Pinus), birch (Betula) and sedges (Cyperaceae) and (iii) reduced canopy cover, possibly to intentionally encourage the growth of taxa such as hazel (Corylus), but that also promoted the establishment of pioneer plants such as mugwort (Artemisia) and bracken (Pteridium).

Cybervictim vs. cyberaggressor. profile determination and comparison through artificial neural networks

ABSTRACT This research aims to determine the magnitude to which aspects of the sociodemographic profile of students (gender, age, religion, ethnicity and race) influence both the acts of harassment received as a cybervictim and those carried out as a cyberaggressor. Additionally, aiming to discover which of these acts suffered as cybervictim or carried out as cyberaggressor increase or decrease to a greater extent, comparing a profile of potential cyberaggressor with another of potential cybervictim. For this purpose, an artificial neural network of the multilayer perceptron type is employed, generating an estimation model of these cybervictim and cyberaggressor facts based on the students’ profile using data obtained through a five-points’ Likert questionnaire. That is especially useful for detecting specific behaviours based on a certain profile, being able to determine which of these attitudes are most at risk of occurring to put the relevant measures in place to prevent them.

Comparison of phytochemical properties and expressional profiling of artemisinin synthesis-related genes in various Artemisia species

The Artemisia genus belongs to the Asteraceae family and is used in the treatment of many different diseases such as hepatitis and cancer. So far, around 500 species of Artemisia have been found in different regions of the world. Artemisinin is one of the medicinal compounds found in Artemisia species. Hence, this medical feature encourages researchers to pay attention to various species of this genus to discover more genetic and phytochemical information. In the present study, five species of Artemisia including A. fragrans, A. annua, A. biennis, A. scoparia, and A. absinthium were compared to each other in terms of the artemisinin content and other phytochemical components. Moreover, the relative expression profiles of eight genes related to the accumulation and synthesis of artemisinin [including 4FPSF, DBR2, HMGR1, HMGR2, WIRKY, ADS, DXS, and SQS] were determined in investigated species. The result of high-performance liquid chromatography (HPLC) analysis showed that the content of artemisinin in various species was in the order of A. fragrans > A. annua > A. biennis > A. scoparia > A. absinthium. Based on the gas chromatography–mass spectrometry (GC-MS) analysis, 34, 26, 26, 24, and 20 phytochemical compounds were identified for A. scoparia, A. biennis, A. fragrans, A. absinthum, and A. annua species, respectively. Moreover, camphor (38.86%), β-thujone (68.42%), spathulenol (48.33%), β-farnesene (48.16%), and camphor (29.04%) were identified as the considerable compounds A. fragrans, A. absinthium, A. scoparia, A. biennis, and A. annua species, respectively. Considering the relative expression of the targeted genes, A. scoparia revealed higher expression for the 4FPSF gene. The highest relative expression of the DBR2, WIRKY, and SQS genes was found in A. absinthium species. Moreover, A. annua showed the highest expression of the ADS and DXS genes than the other species. In conclusion, our findings revealed that various species of Artemisia have interesting breeding potential for further investigation of different aspects such as medicinal properties and molecular studies.

Benchmarking GOCART-2G in the Goddard Earth Observing System (GEOS)

Abstract. The Goddard Chemistry Aerosol Radiation and Transport (GOCART) model, which controls the sources, sinks, and chemistry of aerosols within the Goddard Earth Observing System (GEOS), recently underwent a major refactoring and update, including a revision of the emissions datasets and the addition of brown carbon. A 4-year benchmark simulation utilizing the new version of the model code, termed GOCART Second Generation (GOCART-2G) and coupled to the Goddard Earth Observing System (GEOS) model, was evaluated using in situ and spaceborne measurements to develop a baseline and prioritize future development. A comparison of simulated aerosol optical depth between GOCART-2G and MODIS retrievals indicates the model captures the overall spatial pattern and seasonal cycle of aerosol optical depth but overestimates aerosol extinction over dusty regions and underestimates aerosol extinction over Northern Hemisphere boreal forests, requiring further investigation and tuning of emissions. This MODIS-based analysis is corroborated by comparisons to MISR and selected AERONET stations; however, discrepancies between the Aqua and Terra satellites indicate there is a diurnal component to biases in aerosol optical depth over southern Asia and northern Africa. Despite the underestimate of aerosol optical depth in biomass burning regions in GEOS, there is an overestimate in the surface mass of organic carbon in the United States, especially during the summer months. Over Europe, GOCART-2G is unable to match the summertime peak in aerosol optical depth, opposing the observed late fall and early spring peaks in surface mass concentration. A comparison of the vertical profile of attenuated backscatter to observations from CALIPSO indicates the GEOS model is capable of capturing the vertical profile of aerosol; however, the mid-troposphere plumes of dust in the North Atlantic and smoke in the southeastern Atlantic are perhaps too low in altitude. The results presented highlight priorities for future development with GOCART-2G, including improvements for dust, biomass burning aerosols, and anthropogenic aerosols.

Direct numerical simulation of a pressurized thermal shock scenario at higher reynolds number

Direct Numerical Simulation (DNS) is performed for a pressurized thermal shock scenario in a reactor downcomer geometry. In the present work, a simplified representative geometry is adopted where cold fluid injected from a square duct is injected in a planar downcomer. A secondary hot inlet at the top of the downcomer is employed to enforce a downward flow of the injected emergency core cooling water, to mimic the effect of density driven flow. The Reynolds number of the impinging flow, based on bulk velocity and duct height, equals 12,500, while a unity Prandtl number fluid is used. The simulation is performed for two thermal boundary conditions, namely an isotemperature condition and an adiabatic condition, representing the two extreme scenarios of a conjugate heat transfer problem. The instantaneous and mean fields are first analysed in order to study the flow pattern and formation of vortical structures within the downcomer. The impinging flow is deflected radially outwards in the vicinity of the barrel wall, which then interacts with the surrounding hot fluid forming large vortical structures and bringing the cold fluid back to the vessel wall. The mixing of flow and penetration of colder temperatures in the downcomer is observed to be greatly influenced by interaction of these vortical structures. The descending cold plume in the downcomer is observed to form three branches separated by low-speed regions. The maximum values of turbulent kinetic energy are observed only in the vicinity of flow impingement, while high values of its production and dissipation are also observed within the shear layers of the descending plume. The maximum values of temperature fluctuations are found at the interface of the descending cold plume and surrounding hot fluid, while relatively high values are also seen at the locations of large vortical strucutres. Anisotropy in turbulence is also analysed using the componentality contour approach and a modified barycentric colour mapping scheme. Also reported herein is a comparison of mean and statistical profiles with those at lower Reynolds number reported in the literature. At higher Reynolds number, the cold impinging jet is deflected farther outwards in the downcomer. The locations of peak fluctuations in velocity and temperature are also farther away from the impingement. The magnitudes of fluctuating temperature and turbulent kinetic energy are observed to be higher for the present higher Reynolds number case. The peak Nusselt number at the barrel wall is observed to scale with a factor of Re1/2 in the present configuration.

Exhaled Breath Analysis Detects the Clearance of Staphylococcus aureus from the Airways of Children with Cystic Fibrosis.

Electronic nose (eNose) technology can be used to characterize volatile organic compound (VOC) mixes in breath. While previous reports have shown that eNose can detect lung infections with pathogens such as Staphylococcus aureus (SA) in people with cystic fibrosis (CF), the clinical utility of eNose for longitudinally monitoring SA infection status is unknown. In this longitudinal study, a cloud-connected eNose, the SpiroNose, was used for the breath profile analysis of children with CF at two stable visits and compared based on changes in SA infection status between visits. Data analysis involved advanced sensor signal processing, ambient correction, and statistics based on the comparison of breath profiles between baseline and follow-up visits. Seventy-two children with CF, with a mean (IQR) age of 13.8 (9.8-16.4) years, were studied. In those with SA-positive airway cultures at baseline but SA-negative cultures at follow-up (n = 19), significant signal differences were detected between Baseline and Follow-up at three distinct eNose sensors, i.e., S4 (p = 0.047), S6 (p = 0.014), and S7 (p = 0.014). Sensor signal changes with the clearance of SA from airways were unrelated to antibiotic treatment. No changes in sensor signals were seen in patients with unchanged infection status between visits. Our results demonstrate the potential applicability of the eNose as a non-invasive clinical tool to longitudinally monitor pulmonary SA infection status in children with CF.