KF-Containing Interphase Formation Enables Better Potassium Ion Storage Capability.

Rechargeable potassium ion batteries have long been regarded as one alternative to conventional lithium ion batteries because of their resource sustainability and cost advantages. However, the compatibility between anodes and electrolytes remains to be resolved, impeding their commercial adoption. In this work, the K-ion storage properties of Bi nanoparticles encapsulated in N-doped carbon nanocomposites have been examined in two typical electrolyte solutions, which show a significant effect on potassium insertion/removal processes. In a KFSI-based electrolyte, the N-C@Bi nanocomposites exhibit a high specific capacity of 255.2 mAh g-1 at 0.5 A g-1, which remains at 245.6 mAh g-1 after 50 cycles, corresponding to a high capacity retention rate of 96.24%. In a KPF6-based electrolyte, the N-C@Bi nanocomposites show a specific capacity of 209.0 mAh g-1, which remains at 71.5 mAh g-1 after 50 cycles, corresponding to an inferior capacity retention rate of only 34.21%. Post-investigations reveal the formation of a KF interphase derived from salt decomposition and an intact rod-like morphology after cycling in K2 electrolytes, which are responsible for better K-ion storage properties.

Electromagnetic-acoustic splitter with a tunable splitting ratio based on copper plates.

Acoustic splitters and electromagnetic splitters can be applied in various fields (e.g., navigation and interference detection). However, there is still a lack of study of structures that can simultaneously split acoustic and electromagnetic beams. In this study, a novel, to the best of our knowledge, electromagnetic-acoustic splitter (EAS) based on copper plates is proposed, which can simultaneously produce identical beam-splitting effects for transverse magnetic (TM)-polarized electromagnetic and acoustic waves. Different from previous beam splitters, the beam splitting ratio of the proposed passive EAS can be simply tuned by changing the incident angle of the input beam, i.e., a tunable splitting ratio can be achieved without additional energy consumption. The simulated results verify that the proposed EAS can create two transmitted split beams with a tunable splitting ratio for both electromagnetic and acoustic waves. This may have applications in dual-field navigation/detection, which can provide additional information and higher accuracy compared with single-field navigation/detection.

ATAD3A stabilizes GRP78 to suppress ER stress for acquired chemoresistance in colorectal cancer.

AAA domain containing 3A (ATAD3A) is a nucleus-encoded mitochondrial protein with vital function in communication between endoplasmic reticulum (ER) and mitochondria which is participated in cancer metastasis. Here we show that elevated ATAD3A expression is clinically associated with poor 5-year disease-free survival in patients with colorectal cancer (CRC), especially high-risk CRC patients who received adjuvant chemotherapy. Our results indicated ATAD3A is significantly upregulated to reduce chemotherapy-induced cancer cell death. We found that knockdown of ATAD3A leads to dysregulation in protein processing for inducing ER stress by RNA sequencing (RNA-seq). In response to chemotherapy-induced ER stress, ATAD3A interacts with elevated GRP78 protein to assist protein folding and alleviate ER stress for cancer cell survival. This reduction of ER stress leads to reduce the surface exposure of calreticulin, which is the initiator of immunogenic cell death and antitumor immunity. However, silencing of ATAD3A enhances cell death, triggers the feasibility of chemotherapy-induced ER stress for antitumor immunity, increases infiltration of T lymphocytes and delays tumor regrowth in vitro and in vivo. Clinically, CRC patients with less ATAD3A have high density of CD45+ intratumoral infiltrating lymphocytes (TILs) and memory CD45RO+ TILs. Taken together, our results suggest that pharmacologic targeting to ATAD3A might be a potential therapeutic strategy to enhance antitumor immunity for CRC patients who received adjuvant chemotherapy.

Data-driven interdisciplinary mathematical modelling quantitatively unveils competition dynamics of co-circulating influenza strains.

BACKGROUND: Co-circulation of influenza strains is common to seasonal epidemics and pandemic emergence. Competition was considered involved in the vicissitudes of co-circulating influenza strains but never quantitatively studied at the human population level. The main purpose of the study was to explore the competition dynamics of co-circulating influenza strains in a quantitative way. METHODS: We constructed a heterogeneous dynamic transmission model and ran the model to fit the weekly A/H1N1 influenza virus isolation rate through an influenza season. The construction process started on the 2007-2008 single-clade influenza season and, with the contribution from the clade-based A/H1N1 epidemiological curves, advanced to the 2008-2009 two-clade influenza season. Pearson method was used to estimate the correlation coefficient between the simulated epidemic curve and the observed weekly A/H1N1 influenza virus isolation rate curve. RESULTS: The model found the potentially best-fit simulation with correlation coefficient up to 96% and all the successful simulations converging to the best-fit. The annual effective reproductive number of each co-circulating influenza strain was estimated. We found that, during the 2008-2009 influenza season, the annual effective reproductive number of the succeeding A/H1N1 clade 2B-2, carrying H275Y mutation in the neuraminidase, was estimated around 1.65. As to the preceding A/H1N1 clade 2C-2, the annual effective reproductive number would originally be equivalent to 1.65 but finally took on around 0.75 after the emergence of clade 2B-2. The model reported that clade 2B-2 outcompeted for the 2008-2009 influenza season mainly because clade 2C-2 suffered from a reduction of transmission fitness of around 71% on encountering the former. CONCLUSIONS: We conclude that interdisciplinary data-driven mathematical modelling could bring to light the transmission dynamics of the A/H1N1 H275Y strains during the 2007-2009 influenza seasons worldwide and may inspire us to tackle the continually emerging drug-resistant A/H1N1pdm09 strains. Furthermore, we provide a prospective approach through mathematical modelling to solving a seemingly unintelligible problem at the human population level and look forward to its application at molecular level through bridging the resolution capacities of related disciplines.

SMART: Statistical Metabolomics Analysis-An R Tool.

Metabolomics data provide unprecedented opportunities to decipher metabolic mechanisms by analyzing hundreds to thousands of metabolites. Data quality concerns and complex batch effects in metabolomics must be appropriately addressed through statistical analysis. This study developed an integrated analysis tool for metabolomics studies to streamline the complete analysis flow from initial data preprocessing to downstream association analysis. We developed Statistical Metabolomics Analysis-An R Tool (SMART), which can analyze input files with different formats, visually represent various types of data features, implement peak alignment and annotation, conduct quality control for samples and peaks, explore batch effects, and perform association analysis. A pharmacometabolomics study of antihypertensive medication was conducted and data were analyzed using SMART. Neuromedin N was identified as a metabolite significantly associated with angiotensin-converting-enzyme inhibitors in our metabolome-wide association analysis (p = 1.56 × 10(-4) in an analysis of covariance (ANCOVA) with an adjustment for unknown latent groups and p = 1.02 × 10(-4) in an ANCOVA with an adjustment for hidden substructures). This endogenous neuropeptide is highly related to neurotensin and neuromedin U, which are involved in blood pressure regulation and smooth muscle contraction. The SMART software, a user guide, and example data can be downloaded from http://www.stat.sinica.edu.tw/hsinchou/metabolomics/SMART.htm .

Mycobacterium tuberculosis nucleic acid amplification tests reduce nosocomial tuberculosis exposure in intensive care units: A nationwide cohort study.

BACKGROUND AND OBJECTIVE: This retrospective national surveillance study investigated the burden of and risk factors for nosocomial exposure of pulmonary tuberculosis (TB) in intensive care units. METHODS: Patients admitted to intensive care units were identified from the National Health Insurance Research Database. During 2004-2009, there were 1 387 707 intensive care unit admissions of 900 562 adult patients. Pulmonary tuberculosis association was considered if the patient was diagnosed with pulmonary tuberculosis during admission or within 3 months after discharge. Nosocomial transmissible period was calculated based on the length of anti-tuberculosis treatment and negative-pressure isolation during admission. RESULTS: Pulmonary tuberculosis was associated with 1.20% of all intensive care unit admissions and 6731 (38.9%) started anti-TB treatment during admission. For the other 10 583 admissions, the diagnosis was made after discharge and anti-TB treatment was not prescribed during admission. The probability paralleled the regional tuberculosis incidence. On average, 2794 pulmonary tuberculosis associated intensive care unit admissions contributed to 42 999-44 062 days of nosocomial exposure per year. The length of nosocomial transmissible period decreased with the gradual implementation of Mycobacterium tuberculosis nucleic acid amplification tests in intensive care practice. Multivariate linear regression analysis revealed that the length of nosocomial transmissible period was inversely associated with male gender, airway symptoms prior to admission and performing M. tuberculosis nucleic acid amplification tests and mycobacterial culture. CONCLUSIONS: Nosocomial tuberculosis exposure is not uncommon in intensive care units. Performing rapid molecular diagnostic tests in those suspected of tuberculosis is recommended to reduce the risk of nosocomial exposure.

A fault-tolerant method for HLA typing with PacBio data.

BACKGROUND: Human leukocyte antigen (HLA) genes are critical genes involved in important biomedical aspects, including organ transplantation, autoimmune diseases and infectious diseases. The gene family contains the most polymorphic genes in humans and the difference between two alleles is only a single base pair substitution in many cases. The next generation sequencing (NGS) technologies could be used for high throughput HLA typing but in silico methods are still needed to correctly assign the alleles of a sample. Computer scientists have developed such methods for various NGS platforms, such as Illumina, Roche 454 and Ion Torrent, based on the characteristics of the reads they generate. However, the method for PacBio reads was less addressed, probably owing to its high error rates. The PacBio system has the longest read length among available NGS platforms, and therefore is the only platform capable of having exon 2 and exon 3 of HLA genes on the same read to unequivocally solve the ambiguity problem caused by the "phasing" issue. RESULTS: We proposed a new method BayesTyping1 to assign HLA alleles for PacBio circular consensus sequencing reads using Bayes' theorem. The method was applied to simulated data of the three loci HLA-A, HLA-B and HLA-DRB1. The experimental results showed its capability to tolerate the disturbance of sequencing errors and external noise reads. CONCLUSIONS: The BayesTyping1 method could overcome the problems of HLA typing using PacBio reads, which mostly arise from sequencing errors of PacBio reads and the divergence of HLA genes, to some extent.

Can venture capital shareholding improve M&A performance? An empirical study based on Chinese GEM-listed companies.

Existing studies have explored the impact of venture capital shareholding on the GEM-listed companies before and after listing from multiple perspectives. However, there has been limited research on the influence of venture capital shareholding on these companies' mergers and acquisitions(M&A) activities and performance. Additionally, two conflicting research findings have been presented in limited relevant studies. In order to clarify the mechanism by which venture capital shareholding affects M&A activities and performance of GEM-listed companies and verify existing research conclusions, this paper takes 468 M&A events completed by the acquirer of China's GEM-listed companies between 2014 and 2016 as samples to explore venture capital shareholding's effects on the M&A performance of GEM-listed enterprises. The empirical findings demonstrate that GEM-listed enterprises with venture capital shareholding perform significantly better in terms of short-term and long-term M&A performance than those without; with the increase in venture capital shareholding ratio, the short-term M&A performance of GEM-listed enterprises has remarkably improved, but the long-term M&A performance does not show obvious correlation; joint investment of venture capital can significantly improve the short-term M&A performance of GEM-listed enterprises, but it has no substantial influence on long-term M&A performance. Based on further analysis of the empirical study, it is concluded that the common one-share ownership structure of GEM-listed enterprises is not conducive to the play of the monitoring function of venture capital, and the insufficient incentives and free-riding thinking also weaken the motivation and input of some venture capital shareholders to provide value-added services. This study systematically elucidates the mechanism and impact of venture capital shareholding on the M&A performance of GEM-listed companies, addressing the shortcomings in existing research. It is conducive for GEM-listed companies to gain a rational understanding and effectively leverage the active role of venture capital shareholders in M&A activities.

Anti-epileptic drug use during adjuvant chemo-radiotherapy is associated with poorer survival in patients with glioblastoma: A nationwide population-based cohort study.

INTRODUCTION: There are emerging but inconsistent evidences about anti-epileptic drugs (AEDs) as radio- or chemo-sensitizers to improve survival in glioblastoma patients. We conducted a nationwide population-based study to evaluate the impact of concurrent AED during post-operative chemo-radiotherapy on outcome. MATERIAL AND METHODS: A total of 1057 glioblastoma patients were identified by National Health Insurance Research Database and Cancer Registry in 2008-2015. Eligible criteria included those receiving surgery, adjuvant radiotherapy and temozolomide, and without other cancer diagnoses. Survival between patients taking concurrent AED for 14 days or more during chemo-radiotherapy (AED group) and those who did not (non-AED group) were compared, and subgroup analyses for those with valproic acid (VPA), levetiracetam (LEV), or phenytoin were performed. Multivariate analyses were used to adjust for confounding factors. RESULTS: There were 642 patients in the AED group, whereas 415 in the non-AED group. The demographic data was balanced except trend of more patients in the AED group had previous drug history of AEDs (22.6% vs. 18%, P 0.078). Overall, the AED group had significantly increased risk of mortality (HR = 1.18, P 0.016) compared to the non-AED group. Besides, an adverse dose-dependent relationship on survival was also demonstrated in the AED group (HR = 1.118, P 0.0003). In subgroup analyses, the significant detrimental effect was demonstrated in VPA group (HR = 1.29,P 0.0002), but not in LEV (HR = 1.18, P 0.079) and phenytoin (HR = 0.98, P 0.862). CONCLUSIONS: Improved survival was not observed in patients with concurrent AEDs during chemo-radiotherapy. Our real-world data did not support prophylactic use of AEDs for glioblastoma patients.

Characterization of the key flavor compounds in cream cheese by GC-MS, GC-IMS, sensory analysis and multivariable statistics.

The aroma types of cream cheese affect its commercial value and consumer acceptability. However, the types of volatile substances and sensory characteristics of cream cheese at different fermentation stages are still unclear. Therefore, in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) were used to analyze the volatile substances in cream cheese fermentation. Orthogonal partial least squares discriminant analysis (OPLS-DA), odor activity value (OAV), relative odor activity value (ROAV) and variable projection importance (VIP) were used to identify the characteristic flavor substances in cream cheese fermentation. Finally, the relationship between key flavor substances and sensory characteristics was determined by partial least squares (PLS) analysis. A total of 34 and 36 volatile organic compounds were identified by HS-SPME-GC-MS and HS-GC-MS, respectively, and 14 characteristic flavor substances were found, based on VIP, ROAV and OAV models. Combined with sensory analysis and flavor substance changes, it was found that the cream cheese fermented for 15 d had the best flavor and taste. This study reveals the characteristics and contribution of volatile substances in cream cheese at different fermentation stages, which provides new insights into improving flavor and quality control.

Risk factors for pulmonary tuberculosis in patients with chronic obstructive airway disease in Taiwan: a nationwide cohort study.

BACKGROUND: An association between chronic obstructive pulmonary disease (COPD) and tuberculosis (TB) has been described, mainly due to smoking and corticosteroid use. Whether inhaled corticosteroid (ICS) therapy is associated with an increased risk of TB remains unclear. METHODS: We selected COPD cases by using six diagnostic scenarios and control subjects from a nationwide health insurance database, and applied time-dependent Cox regression analysis to identify the risk factors for TB. RESULTS: Among 1,000,000 beneficiaries, 23,594 COPD cases and 47,188 non-COPD control subjects were selected. Cox regression analysis revealed that age, male gender, diabetes mellitus, end-stage renal disease, and cirrhosis, as well as COPD (hazard ratio = 2.468 [2.205-2.762]) were independent risk factors for TB. Among the COPD cases, those who developed TB received more oral corticosteroids and oral ß-agonists. Time-dependent Cox regression analysis revealed that age, male gender, diabetes mellitus, low income, oral corticosteroid dose, and oral ß-agonist dose, but not ICS dose, were independent risk factors for TB. The identified risk factors and their hazard ratios were similar among the COPD cases selected using different scenarios. CONCLUSION: Keeping a high suspicion and regularly monitoring for the development of pulmonary TB in COPD patients are necessary, especially for those receiving higher doses of oral corticosteroids and other COPD medications. Although ICS therapy has been shown to predispose COPD patients to pneumonia in large randomized clinical trials, it does not increase the risk of TB in real world practice.

Tissue compliance meter is a more reproducible method of measuring radiation-induced fibrosis than late effects of normal tissue-subjective objective management analytical in patients treated with intracavitary brachytherapy accelerated partial breast irradiation: results of a prospective trial.

Identification of radiation-induced fibrosis (RIF) remains a challenge with Late Effects of Normal Tissue-Subjective Objective Management Analytical (LENT-SOMA). Tissue compliance meter (TCM), a non-invasive applicator, may render a more reproducible tool for measuring RIF. In this study, we prospectively quantify RIF after intracavitary brachytherapy (IB) accelerated partial breast irradiation (APBI) with TCM and compare it with LENT-SOMA. Thirty-nine women with American Joint Committee on Cancer Stages 0-I breast cancer, treated with lumpectomy and intracavitary brachytherapy delivered by accelerated partial breast irradiation (IBAPBI), were evaluated by two raters in a prospective manner pre-IBAPBI and every 6 months post-IBAPBI for development of RIF, using TCM and LENT-SOMA. TCM classification scale grades RIF as 0 = none, 1 = mild, 2 = moderate, and 3 = severe, corresponding to a change in TCM (ΔTCM) between the IBAPBI and nonirradiated breasts of ≤2.9, 3.0-5.9, 6.0-8.9, ≥9.0 mm, respectively. LENT-SOMA scale employs clinical palpation to grade RIF as 0 = none, 1 = mild, 2 = moderate, and 3 = severe. Correlation coefficients-Intraclass (ICC), Pearson (r), and Cohen's kappa (κ)-were employed to assess reliability of TCM and LENT-SOMA. Multivariate and univariate linear models explored the relationship between RIF and anatomical parameters [bra cup size], antihormonal therapy, and dosimetric factors [balloon diameter, skin-to-balloon distance (SBD), V150, and V200]. Median time to follow-up from completion of IBAPBI is 3.6 years (range, 0.8-4.9 years). Median age is 69 years (range, 47-82 years). Median breast cup size is 39D (range, 34B-44DDD). Median balloon size is 41.2 cc (range, 37.6-50.0 cc), and median SBD is 1.4 cm (range, 0.2-5.5 cm). At pre-IBAPBI, TCM measurements demonstrate high interobserver agreement between two raters in all four quadrants of both breasts ICC ≥ 0.997 (95% CI 0.994-1.000). After 36 months, RIF is graded by TCM scale as 0, 1, 2, and 3 in 10/39 (26%), 17/39 (43%), 9/39 (23%), and 3/39 (8%) of patients, respectively. ΔTCM ≥6 mm (moderate-severe RIF) is statistically different from ΔTCM ≤3 mm (none-mild RIF) (p < 0.05). At 36 months post-IBAPBI, TCM measurements for two raters render ICC = 0.992 (95% CI 0.987-0.995) and r = 0.983 (p < 0.0001), whereas LENT-SOMA demonstrates κ = 0.45 (95% CI 0.18-0.80). SBD and V150 are the only factors closest to 0.05 significance of contributing to RIF. This prospective study indicates that TCM is a more reproducible method than LENT-SOMA in measuring RIF in patients treated with IBAPBI. This tool renders a promising future application in assessing RIF.

Assessment of pain as a sequela in patients treated with intracavitary brachytherapy accelerated partial breast irradiation (IBAPBI): preliminary results of a prospective study.

To assess pain rates and relationship to radiation-induced fibrosis (RIF) in patients treated with intracavitary brachytherapy accelerated partial breast irradiation (IBAPBI). Thirty-nine patients treated with IBAPBI were assessed prospectively for development of pain pretreatment, 1 month post-IBAPBI, and every 6 months thereafter. A qualitative subjective Late Effects of Normal Tissue-Subjective Objective Management Analytical (LENT-SOMA) questionnaire assessed pain. Use of pain medications was assessed as "no", "sometimes", or "regularly". A quantitative objective validated pressure threshold (PTH) measured pain in the site of IBAPBI breast (index) and its mirror-image in the nonirradiated breast (control). A validated tissue compliance meter (TCM) quantitatively assessed RIF in the index and control breasts at all time points. Mean ΔPTH(kg) and ΔTCM(mm) values reflected mean difference between the index and control breasts. Median follow-up is 44 months (range 5-59 months). According to LENT-SOMA, pain occurred in 89% at 1 and 24 months, 67% at 30 months, 30% at 36 months, 29% at 40 months, and 20% at 48 months. No patient used pain medication "regularly" but the use "sometimes" decreased over time: 61% at 1 month, 42% at 18 and 24 months, 13% at 36 months, and 10% at 40 months. Mean ΔPTH values, compared to Δ0 kg at baseline, peaked in absolute value by 1 month to -1.36 kg (p < 0.0001), persisted after 18 months at -0.99 kg (p < 0.0001) and 24 months at -0.73 kg (p < 0.0001), and returned to nearly baseline by 40 months at -0.11 kg (p < 0.57). Mean ΔPTH and ΔTCM correlated significantly with subjective patient reports of pain at each time point (p < 0.0001). To date, this is the first report to prospectively assess pain employing quantitative and qualitative inventories in patients treated with IBAPBI. Pain is experienced in the majority of patients experienced pain within the first 2 years, sometimes requiring a medication, and though subsides, it may persist 4 years after IBAPBI.

Effect of initial temperature on water aggregation at a cold surface.

Cellular automata models of water at two initial temperatures were created. Each model was exposed to a freezing surface. The formation of fully bonded water cells, f(4), was observed over time, beginning with a model of initially warm water and with initially cool water. The warm water formed more f(4) cells earlier than the initially cool water. A high percentage of f(4) cells is interpreted as the formation of ice. This is a model of the Mpemba effect. A description of the initial states for these two temperatures is offered in explanation of this effect.

A cellular automata model of proton hopping down a channel.

Proton hopping is the process where a H-atom on a hydronium ion forms a H-bond with the O-atom of a neighboring H(2)O molecule. There is then an exchange of bonding forces when that covalent bond of the H-atom in the hydronium ion changes to a H-bond, and the previous H-bond changes to a covalent bond with the neighboring O-atom. The neighboring molecule now becomes a hydronium (H(3)O(+)) ion. This process repeats itself very rapidly among neighboring hydronium and H(2)O molecules. There is a flow of protonic character through bulk H(2)O, referred to as proton hopping. This process carries information through living systems where H(2)O is present. A cellular automata model of proton hopping down a channel has been created and studied. Variations in the rate of proton entry into the channel and the effects of the polar character of the channel walls was studied using the model. The behavior of the models corresponds to experimental results.

Active Thermal Metasurfaces for Remote Heating/Cooling by Mimicking Negative Thermal Conductivity.

Remote temperature control can be obtained by a long-focus thermal lens that can focus heat fluxes into a spot far from the back surface of the lens and create a virtual thermal source/sink in the background material, around which the temperature field distribution can be remotely controlled by varying the parameters of the thermal lens. However, because of the lack of negative thermal conductivity, existing thermal lenses have extremely short focal lengths and cannot be used to remotely control the temperature field around the virtual thermal source/sink. In this study, a general approach is proposed to equivalently realize materials with negative thermal conductivity using elaborately distributed active thermal metasurfaces (ATMSs). Subsequently, the proposed ATMS is used to implement a novel thermal lens with a long focal length designed using transformation thermodynamics, and finally realize the ATMS with realistic materials and experimentally verify the performance of the designed long-focus thermal lens (measured focal length of 19.8 mm) for remote heating/cooling. The proposed method expands the scope of the thermal conductivity and provides new pathways to realize unprecedented thermal effects with effective negative thermal conductivity, such as "thermal surface plasmon polaritons," a thermal superlens, the thermal tunneling effect, and the thermal invisible gateway.

GC-MS and GC×GC-ToF-MS analysis of roasted / broth flavors produced by Maillard reaction system of cysteine-xylose-glutamate.

Maillard reaction products (MRPs) with roasted/broth flavors were prepared and analyzed for the resulting flavor differences. The identification of volatile compounds in MRPs was carried out by GC-MS and GC × GC-ToF-MS. A total of 88 compounds were identified by GC-MS; 130 compounds were identified by GC × GC-ToF-MS, especially acids and ketones were identified. Principal component analysis (PCA) was used to visualize the volatile compounds, and the roasted/broth flavors were differentiated. The contents and types of pyrazines were more in roasted flavors; thiol sulfides and thiophenes were more in broth flavors. All in all, the differences in volatile compounds producing roasted/broth flavors were studied through the cysteine-xylose-glutamate Maillard reaction system, which provided a theoretical basis for the future use of Maillard reaction to simulate meat flavor.

Characterization of a fermented dairy, sour cream: Lipolysis and the release profile of flavor compounds.

Lipolysis and flavor development during fermentation of sour cream were studied by evaluating the physicochemical changes, sensory differences and volatile components. The fermentation caused significant changes in pH, viable count and sensory evaluation. The peroxide value (POV) decreased after reaching the maximum value of 1.07 meq/kg at 15 h, while thiobarbituric acid reactive substances (TBARS) increased continuously with the accumulation of secondary oxidation products. The Free fatty acids (FFAs) in sour cream were mainly myristic, palmitic and stearic. GC-IMS was used to identify the flavor properties. A total of 31 volatile compounds were identified, among which the contents of characteristic aromatic substances such as ethyl acetate, 1-octen-3-one and hexanoic acid were increased. The results suggest that lipid changes and flavor formation in sour cream are influenced by fermentation time. Furthermore, flavor compounds may be related to lipolysis such as 1-octen-3-one and 2- heptanol were also observed.

Effects of Reducing Sugars on the Structural and Flavor Properties of the Maillard Reaction Products of Lycium barbarum Seed Meal.

Lycium barbarum seed meal contains a variety of bioactive compounds, but the use of L. barbarum seed meal in the food industry is rare. This study aimed to evaluate the effect of reducing sugars on the structural and flavor properties of the Maillard reaction products (MRPs) of the Lycium barbarum seed meal hydrolysate (LSH). The results showed that the flavors and tastes of the MRPs were affected by reducing sugars. In comparison to oligosaccharides, monosaccharides were more suitable for the development of MRPs with good sensory qualities. The structural characteristics of L. barbarum seed meal precursor MRPs were also affected by reducing sugars. The MRPs produced with the participation of monosaccharides had higher ultraviolet absorption and browning than the MRPs produced with oligosaccharides. The molecular weights of the MRPs were found to be 128-500 Da and 500-1000 Da. Compared to the MRPs made from other sugars, xylose-meridian products (X-MRPs) had a stronger meaty flavor. The mellowness and continuity of the MRPs made from monosaccharides were superior to those made from oligosaccharides. The MRPs formed by L. barbarum seed meal exhibited the characteristics of umami and meat flavor. MRPs with better flavors may be used to develop new types of seasoning salts.