Evaluation of pancreatic iodine uptake and related influential factors in multiphase dual-energy CT.

OBJECTIVES: To establish normative values and identify potential factors influencing pancreatic iodine uptake using dual-energy CT (DECT). MATERIALS AND METHODS: This retrospective study included participants without pancreatic diseases undergoing DECT at two institutions with different platforms. Their protocols both included arterial phase (AP), portal venous phase (PP), and equilibrium phase (EP), defined as 35 s-40 s, 60 s-70 s, and 150 s-180 s after injection of contrast agent, respectively. Both iodine concentration (IC) and normalised IC (NIC) were measured. Demographic features, local measurements of the pancreas and visceral fat area (VFA) were considered as potential factors influencing iodine uptake using multivariate linear regression analyses. RESULTS: A total of 562 participants (median age 58 years [interquartile range: 47-67], with 282 men) were evaluated. The mean IC differed significantly between two institutions (all p < 0.001) across three contrast-enhanced phases, while the mean NIC showed no significant differences (all p > 0.05). The mean values of NIC were 0.22 at AP, 0.43 at PP and 0.45 at EP. NICAP was independently affected by VFA (ß = 0.362, p < 0.001), smoking (ß = -0.240, p = 0.001), and type-II diabetes (ß = -0.449, p < 0.001); NICPP by VFA (ß = -0.301, p = 0.017) and smoking (ß = -0.291, p < 0.001); and NICEP by smoking (ß = -0.154, p = 0.10) and alcohol consumption (ß = -0.350, p < 0.001) with statistical power values over 0.81. CONCLUSION: NIC values were consistent across institutions. Abdominal obesity, smoking, alcohol consumption, and diabetes are independent factors influencing pancreatic iodine uptake. CLINICAL RELEVANCE STATEMENT: This study has provided reference normative values, influential factors and effective normalisation methods of pancreatic iodine uptake in multiphase dual-energy CT for future studies in this area as a new biological marker. KEY POINTS: Evaluation of pancreatic iodine uptake measured by dual-energy CT is a promising method for future studies. Abdominal obesity, smoking, alcohol consumption, diabetes, and sex are independent factors influencing pancreatic iodine uptake. Utility of normalised iodine concentration is necessary to ensure the consistency across different institutions.

Circadian Rhythms Correlated in DNA Methylation and Gene Expression Identified in Human Blood and Implicated in Psychiatric Disorders.

Circadian rhythms modulate the biology of many human tissues and are driven by a nearly 24-h transcriptional feedback loop. Dynamic DNA methylation may play a role in driving 24-h rhythms of gene expression in the human brain. However, little is known about the degree of circadian regulation between the DNA methylation and the gene expression in the peripheral tissues, including human blood. We hypothesized that 24-h rhythms of DNA methylation play a role in driving 24-h RNA expression in human blood. To test this hypothesis, we analyzed DNA methylation levels and RNA expression in blood samples collected from eight healthy males at six-time points over 24 h. We assessed 442,703 genome-wide CpG sites in methylation and 12,364 genes in expression for 24-h rhythmicity using the cosine model. Our analysis revealed significant rhythmic patterns in 6345 CpG sites and 21 genes. Next, we investigated the relationship between methylation and expression using powerful circadian signals. We found a modest negative correlation (ρ = -0.83, p = 0.06) between the expression of gene TXNDC5 and the methylation at the nearby CpG site (cg19116172). We also observed that circadian CpGs significantly overlapped with genetic risk loci of schizophrenia and autism spectrum disorders. Notably, one gene, TXNDC5, showed a significant correlation between circadian methylation and expression and has been reported to be association with neuropsychiatric diseases.

The metabolic score for insulin resistance as a predictor of clinical outcome in stroke patients treated by intravenous thrombolysis.

BACKGROUND AND PURPOSE: Insulin resistance is associated with clinical outcomes among patients with ischemic stroke. We aimed to investigate the association between metabolic score for insulin resistance (METS-IR) and clinical outcomes in stroke patients treated by intravenous thrombolysis (IVT). METHODS: We recruited participants treated with IVT from a prospective registry including 3 stroke centers. Poor outcome was defined as a modified Rankin scale score ≥ 3 points at 90 days after the index stroke. We performed logistic regression models to investigate the association between METS-IR and the risk of poor outcome. We used the receiver operative characteristic to assess the discriminative ability and the restricted cubic spline to explore the relationship between METS-IR and the poor outcome. RESULTS: This study enrolled a total of 1074 patients (median age, 68; 63.8% male). Three hundred sixty (33.5%) patients had poor outcome after IVT. METS-IR was associated with the risk of the poor outcome with the increase of confounding factors in models (odds ratio [OR], 1.078; 95% confidence interval [CI], 1.058-1.099; P < 0.001). The area under the curve for METS-IR for predicting the poor outcome was 0.790 (95% CI, 0.761-0.819). The restricted cubic spline revealed an increasing and non-linear association between METS-IR and the poor outcome (P for non-linearity < 0.001). CONCLUSION: Our study found that METS-IR was associated with an increased risk of poor outcome after IVT. Further studies are warranted to investigate the efficacy of anti-diabetic agents regarding IR on clinical outcomes after IVT.

A score of non-contrast transthoracic echocardiography to screen patent foramen ovale in patients with embolic stroke of undetermined source.

BACKGROUND: The aim of this study was to develop a screening score system of non-contrast transthoracic echocardiography (TTE) for patent foramen ovale (PFO) in patients with embolic stroke of undetermined source (ESUS). METHODS: We performed a retrospective analysis of 218 consecutive patients with a recent ESUS from 2015 to 2018, who received TTE and transcranial Doppler (TCD) as routine examinations. PFO was diagnosed by the bubble test of TCD. Significant differences of the non-contrast TTE findings and patient characteristics between PFO group and non-PFO group were selected into a score. RESULTS: PFO was diagnosed in 35.8% (78/218) of the patients. Compared with non-PFO group, a larger median aortic root diameter (ARd) (34 mm vs. 32 mm, p = 0.005), a lower median peak E wave velocity (Em) (61.5 cm/s vs. 68 cm/s, p = 0.005) and a lower incidence rate of mitral regurgitation (34.6% vs. 50.7%, p = 0.022) were seen in PFO group. ARd>33 mm and Em < 72 cm/s were the best thresholds to predict PFO in ROC analysis. A four-point score system (MEAD) including TTE criteria (including ARd>33 mm, Em < 72 cm/s and without mitral regurgitation) and no history of diabetes predicted PFO with an area under curve of 0.67 (95%CI 0.57-0.72, p < 0.001). MEAD score ≥ 3 was the best threshold to predict PFO with an accuracy of 0.64 (95% CI 0.57-0.7), a sensitivity of 0.65 (95% CI 0.53-0.75) and a specificity of 0.63 (95% CI 0.55-0.71). CONCLUSION: The MEAD score measured with non-contrast TTE can be used to select patients for bubble test of TCD to increase the diagnostic yield of PFO after ESUS.

Experiences of bowel symptoms in patients with rectal cancer after sphincter-preserving surgery: a qualitative meta-synthesis.

PURPOSE: This study is to identify and synthesize the available evidence of bowel symptom experiences of patients with rectal cancer after sphincter-preserving surgery (SPS). METHODS: This qualitative meta-synthesis was conducted following the Joanna Briggs Institute (JBI) qualitative systematic review methodology and reported following the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) guidelines. Seven databases were searched on 22 December 2021. The selected studies were reviewed by two independent reviewers, and disagreements were resolved by discussion or with a third reviewer. RESULTS: Seven qualitative articles were included in the meta-synthesis with 192 total rectal cancer patients. The review summarized 53 qualitative findings into three synthesized findings: (a) Patients experienced bowel symptoms and triggered additional physiological problems, and they underestimated bowel symptoms; (b) patients had many negative emotions, and their daily life and social interaction were disturbed; and (c) patients adopted strategies to adapt or control their bowel symptoms. According to the ConQual evidence grading approach, the confidence of the synthesized findings was rated as moderate to low. CONCLUSIONS: The bowel symptoms of patients with rectal cancer after SPS have troubled their lives. Timely acquisition of symptom-related knowledge and enhancement of their coping abilities are important for the control and management of bowel symptoms. Healthcare professionals should clearly understand the bowel symptoms that patients may experience after SPS and provide supportive care for patients to improve patients' self-management abilities and quality of life. TRIAL REGISTRATION: PROSPERO: CRD42021242610.

Correlation of Key Physiological Properties of Methanosarcina Isolates with Environment of Origin.

It is known that the physiology of Methanosarcina species can differ significantly, but the ecological impact of these differences is unclear. We recovered two strains of Methanosarcina from two different ecosystems with a similar enrichment and isolation method. Both strains had the same ability to metabolize organic substrates and participate in direct interspecies electron transfer but also had major physiological differences. Strain DH-1, which was isolated from an anaerobic digester, used H2 as an electron donor. Genome analysis indicated that it lacks an Rnf complex and conserves energy from acetate metabolism via intracellular H2 cycling. In contrast, strain DH-2, a subsurface isolate, lacks hydrogenases required for H2 uptake and cycling and has an Rnf complex for energy conservation when growing on acetate. Further analysis of the genomes of previously described isolates, as well as phylogenetic and metagenomic data on uncultured Methanosarcina in anaerobic digesters and diverse soils and sediments, revealed a physiological dichotomy that corresponded with environment of origin. The physiology of type I Methanosarcina revolves around H2 production and consumption. In contrast, type II Methanosarcina species eschew H2 and have genes for an Rnf complex and the multiheme, membrane-bound c-type cytochrome MmcA, shown to be essential for extracellular electron transfer. The distribution of Methanosarcina species in diverse environments suggests that the type I H2-based physiology is well suited for high-energy environments, like anaerobic digesters, whereas type II Rnf/cytochrome-based physiology is an adaptation to the slower, steady-state carbon and electron fluxes common in organic-poor anaerobic soils and sediments. IMPORTANCE Biogenic methane is a significant greenhouse gas, and the conversion of organic wastes to methane is an important bioenergy process. Methanosarcina species play an important role in methane production in many methanogenic soils and sediments as well as anaerobic waste digesters. The studies reported here emphasize that the genus Methanosarcina is composed of two physiologically distinct groups. This is important to recognize when interpreting the role of Methanosarcina in methanogenic environments, especially regarding H2 metabolism. Furthermore, the finding that type I Methanosarcina species predominate in environments with high rates of carbon and electron flux and that type II Methanosarcina species predominate in lower-energy environments suggests that evaluating the relative abundance of type I and type II Methanosarcina may provide further insights into rates of carbon and electron flux in methanogenic environments.

Solvent-Induced Assembly of Microbial Protein Nanowires into Superstructured Bundles.

Protein-based electronic biomaterials represent an attractive alternative to traditional metallic and semiconductor materials due to their environmentally benign production and purification. However, major challenges hindering further development of these materials include (1) limitations associated with processing proteins in organic solvents and (2) difficulties in forming higher-order structures or scaffolds with multilength scale control. This paper addresses both challenges, resulting in the formation of one-dimensional bundles composed of electrically conductive protein nanowires harvested from the microbes Geobacter sulfurreducens and Escherichia coli. Processing these bionanowires from common organic solvents, such as hexane, cyclohexane, and DMF, enabled the production of multilength scale structures composed of distinctly visible pili. Transmission electron microscopy revealed striking images of bundled protein nanowires up to 10 µm in length and with widths ranging from 50-500 nm (representing assembly of tens to hundreds of nanowires). Conductive atomic force microscopy confirmed the presence of an appreciable nanowire conductivity in their bundled state. These results greatly expand the possibilities for fabricating a diverse array of protein nanowire-based electronic device architectures.

The link between lateral trunk flexion in Parkinson's disease and vestibular dysfunction: a clinical study.

INTRODUCTION: Lateral trunk flexion (LTF) is a common postural deformity in Parkinson's disease (PD). Postural control is known to depend on visual, vestibular, and somatosensory information. OBJECTIVES: This study aimed to investigate the relationship between vestibular dysfunction and postural abnormalities in PD patients with LTF. METHODS: We enrolled a total of 19 PD patients with LTF (PD-LTF+) and 19 age- and sex-matched PD patients without LTF (PD-LTF-). All patients underwent vestibular tests, including spontaneous nystagmus, gaze-evoked nystagmus, ocular movements, optokinetic eye test, fast positioning maneuvers, and the bithermal caloric test. RESULTS: Most of the PD-LTF + patients had abnormal vestibular function (11/19), while there were fewer vestibular function injuries in the control group (3/19). In PD-LTF + group, there were 5 patients (5/11, 45.5%) of peripheral vestibular dysfunction, 2 patients (2/11, 18.2%) of central vestibular damage, and 4 patients (4/11, 36.4%) of mixed injuries. The peripheral vestibular deficiencies could be either bilateral (4/9, 44.4%) or unilateral (5/9, 55.6%). The unilateral vestibular dysfunction was ipsilateral to the leaning side in 2 patients and contralateral to the leaning side in the other 3 patients. CONCLUSION: Vestibular dysfunction may be an independent risk factor for LTF in PD patients.

Evaluation of MYORG mutations as a novel cause of primary familial brain calcification.

BACKGROUND: Very recently, the MYORG gene was identified as a novel causative gene for autosomal-recessive primary familial brain calcification. OBJECTIVE: To investigate the clinical, genetic, and neuroradiological characteristics of primary familial brain calcification patients with biallelic MYORG mutations in China. METHODS: We collected clinical and neuroradiological data of 169 Chinese patients with primary familial brain calcification, including 151 sporadic patients and 18 patients from 13 families compatible with an autosomal-recessive mode of inheritance. Mutational analysis of MYORG was performed in the cohort. RESULTS: We identified four, including three novel, MYORG mutations segregating in four families with 5 patients: one nonsense mutation (c.1431C>A, p.Y477*), one missense mutation (c.687G>T, p.W229C), and two nonframeshift indels (c.348_349insCTGGCCTTCCGC, p.116_117insLAFR; c. 428_442delTGCACTTCTTCATCC, p.143_147delLHFFI). The 12-base-pair insertion, c.348_349insCTGGCCTTCCGC, was found in either homozygous or heterozygous state in 2 probands of our cohort and another Chinese primary familial brain calcification patient previously reported on in the literature. Haplotype analysis of our patients harboring the insertion indicated a founder effect in the ethnic Han Chinese population. To date, biallelic MYORG mutations have been reported in 17 patients (including our cohort). Most patients were symptomatic (13 of 17; 76.5%), and the most recurrent symptoms were movement disorders (10 of 17; 58.8%), cognitive decline (7 of 17; 41.2%), and cerebellar symptoms (6 of 17; 35.3%). All patients had calcifications on comprehensive cranial CT, most frequently located in the basal ganglia (17 of 17; 100%), cerebellum (17 of 17; 100%), subcortical white matter (14 of 17; 82.4%), and thalamus (13 of 17; 76.5%). CONCLUSIONS: We confirmed MYORG as a novel causative gene for primary familial brain calcification and further expanded the mutational and phenotypic spectrum of MYORG-related primary familial brain calcification. © 2018 International Parkinson and Movement Disorder Society.

Renal involvement in a silicosis patient - case report and literature review.

A 43-year-old Chinese man with a silicosis history was admitted to our hospital due to bilateral lower extremity edema for 1 year, exacerbating with hematuria for 2 months. He started working as a coal miner 30 years ago, and was diagnosed as silicosis 3 months ago. Lab tests revealed hematuria 3+, proteinuria 3+, and a serum creatinine value 2.47 mg/dl on routine check. He was diagnosed with focal proliferative IgA nephropathy (IgAN) and acute tubulo-interstitial nephritis by renal biopsy. He was treated with corticosteroids and got a remission 4 months later. Immunohistochemical staining showed the deposition of macrophage receptor with collagenous structure (MARCO), nod-like receptor pyrin domain-containing-3 (NLRP3), Caspase-1, apoptosis-associated speck (ASC), interleukin (IL)-1ß, and IL-18 in both glomerular and tubulo-interstitial areas. We proposed that the silicon exposure could be related to his kidney disease in the patient and NLRP3 mediated inflammation might be involved in its pathogenesis which needs further explorations.

Conductive Composite Materials Fabricated from Microbially Produced Protein Nanowires.

Protein-based electronic materials have numerous potential advantages with respect to sustainability and biocompatibility over electronic materials that are synthesized using harsh chemical processes and/or which contain toxic components. The microorganism Geobacter sulfurreducens synthesizes electrically conductive protein nanowires (e-PNs) with high aspect ratios (3 nm × 10-30 µm) from renewable organic feedstocks. Here, the integration of G. Sulfurreducens e-PNs into poly(vinyl alcohol) (PVA) as a host polymer matrix is described. The resultant e-PN/PVA composites exhibit conductivities comparable to PVA-based composites containing synthetic nanowires. The relationship between e-PN density and conductivity of the resultant composites is consistent with percolation theory. These e-PNs confer conductivity to the composites even under extreme conditions, with the highest conductivities achieved from materials prepared at pH 1.5 and temperatures greater than 100 °C. These results demonstrate that e-PNs represent viable and sustainable nanowire compositions for the fabrication of electrically conductive composite materials.

Insights into the impact of flhF inactivation on Campylobacter jejuni colonization of chick and mice gut.

BACKGROUND: Campylobacter jejuni (C. jejuni) is a leading cause of foodborne gastroenteritis worldwide. This bacterium lacks many of the classical virulence factors, and flagellum-associated persistent colonization has been shown to be crucial for its pathogenesis. The flagellum plays a multifunctional role in C. jejuni pathogenesis, and different flagellar elements make diverse contributions. The flhF gene encodes the flagellar biosynthesis regulator, which is important for flagellar biosynthesis. In this study, the influence of flhF on C. jejuni colonization was systematically studied, and the possible mechanisms were also analyzed. RESULTS: The flhF gene has a significant influence on C. jejuni colonization, and its inactivation resulted in severe defects in the commensal colonization of chicks, with approximately 104- to 107-fold reductions (for NCTC 11168 and a C. jejuni isolate respectively) observed in the bacterial caecal loads. Similar effects were observed in mice where the flhF mutant strain completely lost the ability to continuously colonize mice, which cleared the isolate at 7 days post inoculation. Characterization of the phenotypic properties of C. jejuni that influence colonization showed that the adhesion and invasion abilities of the C. jejuni flhF mutant were reduced to approximately 52 and 27% of that of the wild-type strain, respectively. The autoagglutination and biofilm-formation abilities of the flhF mutant strain were also significantly decreased. Further genetic investigation revealed that flhF is continuously upregulated during the infection process, which indicates a close association of this gene with C. jejuni pathogenesis. The transcription of some other infection-related genes that are not directly involved in flagellar assembly were also influenced by its inactivation, with the flagellar coexpressed determinants (Feds) being apparently affected. CONCLUSIONS: Inactivation of flhF has a significant influence on C. jejuni colonization in both birds and mammals. This defect may be caused by the decreased adhesion, invasion, autoagglutination and biofilm-formation abilities of the flhF mutant strain, as well as the influence on the transcription of other infection related genes, which provides insights into this virulence factor and the flagellum mediated co-regulation of C. jejuni pathogenesis.

High YBX1 expression indicates poor prognosis and promotes cell migration and invasion in nasopharyngeal carcinoma.

Y-box binding protein-1 (YBX1) is a multifunctional protein and often acts as an indicator of poor prognosis in cancers. Increasing evidence has shown that the levels of YBX1 protein were closely associated with multidrug resistance, relapse, metastasis and poor prognosis in cancers. However, its role in nasopharyngeal carcinoma (NPC) metastasis remains unknown. In our study, we discovered that the expression of YBX1 was increased in nasopharyngeal carcinoma tissues. YBX1 protein levels positively correlated with T stage and metastasis of NPC patients. Moreover, expression of YBX1 was negatively correlated with membrane E-cadherin levels and positively correlated with Vimentin expression. In vitro, the expression of YBX1 was closely related to the invasive and migratory ability of nasopharyngeal carcinoma cells. Knockdown of YBX1 inhibited migration and invasion in 5-8F cells, and over-expression of YBX1 promoted CNE1 cells migration and invasion. Transforming growth factor-ß1 (TGF-ß1) treatment led to epithelial-to-mesenchymal transition (EMT) in CNE1 cells accompanied by elevated YBX1 expression. On the contrary, knockdown of YBX1 partially inhibited the TGF-ß1-induced CNE1 cell migration, together with changes of EMT-associated markers. Our study revealed that TGF-ß1/YBX1 signaling might be one of novel mechanisms mediating EMT in NPC, providing a new target for the treatment of nasopharyngeal carcinoma.

Quadriceps combined with hip abductor strengthening versus quadriceps strengthening in treating knee osteoarthritis: a study protocol for a randomized controlled trial.

BACKGROUND: Lower limb strengthening, especially the quadriceps training, is of much necessity for patients with knee osteoarthritis (KOA). Previous studies suggest that strengthening of the hip muscles, especially the hip abductor, can potentially relieve the KOA-associated symptoms. Nevertheless, the effects of quadriceps combined with hip abductor strengthening remain unclear. Therefore, the current randomized controlled trial is designed aiming to observe whether quadriceps in combination with hip abductor strengthening can better improve the function and reduce pain in KOA patients than quadriceps training alone. METHODS: A total of 80 subjects with symptomatic KOA will be recruited from the communities and hospital outpatient, and will be randomly assigned to the experiment group (Quadriceps-plus-hip-abductor-strengthening) or the control group (Quadriceps-strengthening). Specifically, participants in the experiment group will complete 4 exercises to train the quadriceps and hip abductor twice a day for 6 weeks at home, while those in the control group will only perform 2 exercises to strengthen the quadriceps. Besides, all patients will also receive usual care management, including health education and physical agent therapy when necessary. Knee pain will be measured using the Visual Analogue Scale (VAS) at baseline, in every week during the course of treatment, as well as 8 and 12 weeks after randomization. Furthermore, knee function will be measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale, and the quality of life will be measured using the MOS Item Short-form Health Survey (SF-36). In this study, several simple tests will be applied to assess the objective function. All the assessments except for VAS will be carried out at baseline, and in the 6th, 8th and 12th weeks respectively. DISCUSSION: Our findings will provide more evidence for the effects of hip abductor strengthening on relieving pain and improving function in KOA patients. Hip abductor strengthening can be added into the muscle training program for KOA patients as a supplementary content if it is proved to be effective. TRIAL REGISTRATION: The current study has been registered with the Chinese Clinical Trials Registry (the registration number is ChiCTR-IOC-15007590 , 3rd December, 2015).

[Effects of indium exposure on relative content of mitochondrial ND1 gene in human peripheral blood lymphocytes in vitro].

OBJECTIVE: To study the effects of indium exposure on the relative content of mitochondrial ND1 gene in lymphocytes. METHODS: Venous blood was obtained from 14 healthy workers and anticoagulated with heparin. Blood lymphocytes were separated and divided into three tube cultures. For two tubes in the exposed group, indium chloride was added to final concentrations of 0.2 mmol/L and 0.8 mmol/L, respectively. For one tube in the control group, an equal volume of normal saline solution was added. After incubation for 72 h, the relative content of mitochondrial gene in each group was determined using quantitative real-time PCR. RESULTS: Lymphocytes exposed to 0.8 mmol/L indium chloride had a significantly higher relative content of mitochondrial gene than those exposed to 0.2 mmol/L indium chloride and those in the control group (P < 0.05, P < 0.05). CONCLUSION: Lymphocytes exposed to a high concentration of indium and its compounds have an elevated relative content of mitochondrial ND1 gene, indicating increased oxidative DNA damage induced by exposure to a high concentration of indium and its compounds.

Increasing breadth of the frontal lobe but decreasing height of the human brain between two Chinese samples from a Neolithic site and from living humans.

Morphological observation and measurements of endocasts have played a vital role in research on the evolution of the human brain. However, endocasts have never been used to investigate how the human brain has evolved since the Neolithic period. We investigated the evolution of the human brain during the Holocene by comparing virtual endocasts from Beiqian site (a Neolithic Chinese site) and a sample of Chinese modern-day humans. Standardized measurements and indices were taken to provide quantification of the overall endocast shape, including the length, breadth, height, frontal breadth, and the ratio of frontal breadth to breadth, as well as the cranial capacity. We found that the height of the endocasts and cranial capacity have decreased between our two samples, whereas the frontal breadth and sexual dimorphism have increased. We argue that these changes can be caused by random genetic mutation and epigenetic change in response to changes in the environment.

Research on the Relative Placement Angle of the Induction Heater and the Channel in a Four-Channel Induction-Heating Tundish.

In order to optimize the application effect of induction heating (IH) tundishes, a four-channel IH tundish is taken as the research object. Based on numerical simulation methods, the influence of different relative placement angles of induction heaters and channels on the electromagnetic field, flow field and temperature field of the tundish is investigated. We focus on comparing the magnetic flux density (B) and electromagnetic force (EMF) distribution of the channel. The results show that regardless of the relative placement angle between the heater and the channel, the distribution of B in the central circular cross-section of the channel is eccentric. When the heater rotates around channel 1 towards the bottom of the tundish, the distribution of B in the central circular cross-section of the channel changes from a horizontal eccentricity to a vertical one. Through the analysis of the B contour in the longitudinal section of the channel, the difference in effective magnetic flux density area (ΔAB) between the upper and lower parts of the channel can be obtained, thereby quantitatively analyzing the distribution of B in this section. The distribution pattern of ΔAB is consistent with the distribution pattern of the electromagnetic force in the vertical direction (FZ) of the channel centerline. The ΔAB and FZ of channel 1 gradually increase as the heater rotates downwards, while those of channel 2 reach their maximum value at a rotation angle of 60°. Compared to the conventional placement, when the heater rotation angle is 60°, the outlet flow velocities at channel 1 and channel 2 decrease by 15% and 12%, respectively. However, the outlet temperature at channel 2 increases by 1.96 K, and the molten steel flow at the outlet of channel 1 and channel 2 no longer exhibits significant downward flow. This shows that when the heater rotation angle is 60°, it has a dual advantage. On the one hand, it is helpful to reduce the erosion of the molten steel on the channel and the bottom of the discharging chamber, and on the other hand, it can more effectively exert the heating effect of the induction heater on the molten steel in the channel. This presents a new approach to enhance the application effectiveness of IH tundish.

A comprehensive metabolomics analysis of volatile and non-volatile compounds in matcha processed from different tea varieties.

Tea varieties play a crucial role on the quality formation of matcha. This research aimed to examine the impact of four specific tea plant varieties (Okumidori, Longjing 43, Zhongcha108, and E'Cha 1) on various aspects of matcha, including sensory evaluation, major components, color quality, volatile and non-volatile metabolomic profiles. The findings revealed that the levels of tea polyphenols, ester catechins, nonester catechins, and amino acids varied among these four varieties. Notably, 177 significant different metabolites, such as phenolic acids, flavonoids, tannins, alkaloids were identified among 1383 non-volatile compounds. In addition, 97 key aroma-active compounds were identified based on their odor activity value exceeding 1. Aldehydes, heterocyclic compounds, and ketones were closely associated with the formation of volatile metabolites. Overall, this study enhances our understanding of how different tea plant varieties impact the quality of matcha, and can provide valuable guidance for improving matcha varieties in a favorable direction.

Non-Targeted Metabolomics Reveals the Effects of Different Rolling Methods on Black Tea Quality.

A non-targeted metabolomics approach and sensory evaluation, coupled with multivariate statistical analysis, systematically uncover the impact of the rolling time on the quality parameters of black tea. GC-MS analysis reveals that a moderate extension of rolling time favorably contributes to the accumulation of characteristic aroma components in black tea. The volatile components reach their highest concentration in black tea samples processed during an 80-min rolling period. UHPLC-Q-TOF/MS analysis demonstrates a substantial decrease in the contents of catechins and flavonoids with an increase in rolling time. Simultaneously, the production of theaflavins, coupled with the degradation of green bitterness volatiles (GBVs), significantly contributes to the formation of endogenous aroma components in black tea. These findings underscore the close relationship between rolling time control and black tea quality, emphasizing that a moderate extension of the rolling time fosters the development of improved black tea flavor quality. The comprehensive quality evaluation indicates that the optimal duration is 80 min. However, the initial 0 to 20 min of rolling is a crucial phase for the genesis and transformation of black tea quality. This study offers valuable insights into the influence of rolling time on black tea quality, potentially enhancing future studies of rolling technology. It provides theoretical guidelines for optimizing the processing of Gongfu black tea.

Aging pattern of the brainstem based on volumetric measurement and optimized surface shape analysis.

The brainstem, a small and crucial structure, is connected to the cerebrum, spinal cord, and cerebellum, playing a vital role in regulating autonomic functions, transmitting motor and sensory information, and modulating cognitive processes, emotions, and consciousness. While previous research has indicated that changes in brainstem anatomy can serve as a biomarker for aging and neurodegenerative diseases, the structural changes that occur in the brainstem during normal aging remain unclear. This study aimed to examine the age- and sex-related differences in the global and local structural measures of the brainstem in 187 healthy adults (ranging in age from 18 to 70 years) using structural magnetic resonance imaging. The findings showed a significant negative age effect on the volume of the two major components of the brainstem: the medulla oblongata and midbrain. The shape analysis revealed that atrophy primarily occurs in specific structures, such as the pyramid, cerebral peduncle, superior and inferior colliculi. Surface area and shape analysis showed a trend of flattening in the aging brainstem. There were no significant differences between the sexes or sex-by-age interactions in brainstem structural measures. These findings provide a systematic description of age associations with brainstem structures in healthy adults and may provide a reference for future research on brain aging and neurodegenerative diseases.