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1.
Micromachines (Basel) ; 15(5)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38793178

ABSTRACT

Resistive random access memory (RRAM) holds great promise for in-memory computing, which is considered the most promising strategy for solving the von Neumann bottleneck. However, there are still significant problems in its application due to the non-uniform performance of RRAM devices. In this work, a bilayer dielectric layer memristor was designed based on the difference in the Gibbs free energy of the oxide. We fabricated Au/Ta2O5/HfO2/Ta/Pt (S3) devices with excellent uniformity. Compared with Au/HfO2/Pt (S1) and Au/Ta2O5/Pt (S2) devices, the S3 device has a low reset voltage fluctuation of 2.44%, and the resistive coefficients of variation are 13.12% and 3.84% in HRS and LRS, respectively, over 200 cycles. Otherwise, the bilayer device has better linearity and more conductance states in multi-state regulation. At the same time, we analyze the physical mechanism of the bilayer device and provide a physical model of ion migration. This work provides a new idea for designing and fabricating resistive devices with stable performance.

2.
Micromachines (Basel) ; 15(4)2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38675329

ABSTRACT

A novel position-sensitive linear winding silicon drift detector (LWSDD) was designed and simulated. On the frontside (anode side), the collecting anodes were set on both sides of the detector, and an S-shaped linear winding cathode strip was arranged in the middle, which can realize independent voltage division and reduce the complexity of external bias resistor chain compared with the traditional linear silicon drift detector. The detectors were arranged in a butterfly shape, which increased the effective area of the detectors and improved the collection efficiency. The linear winding silicon drift detector can obtain one-dimensional position information by measuring the drift time of electrons. The 2D position information of the incident particle is obtained from the anodes coordinates of the readout signal. One-dimensional analytically exact solutions of electric potential and field were obtained for the first time for the linear winding silicon drift detector. The simulation results show that the electric potential distribution inside the detector is uniform, and the "drift channel" inside the detector points to the collecting anodes on both sides, which proves the reasonable and feasible design of the linear winding silicon drift detector.

3.
Sensors (Basel) ; 24(5)2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38474924

ABSTRACT

In this study, a controllable equal-gap large-area silicon drift detector (L-SDD) is designed. The surface leakage current is reduced by reducing the SiO2-Si interface through the new controllable equal-gap design. The design of the equal gap also solves the problem whereby the gap widens due to the larger detector size in the previous SDD design, which leads to a large invalid area of the detector. In this paper, a spiral hexagonal equal-gap L-SDD of 1 cm radius is selected for design calculation, and we implement 3D modeling and simulation of the device. The simulation results show that the internal potential gradient distribution of the L-SDD is uniform and forms a drift electric field, with the direction of electron drift pointing towards the collecting anode. The L-SDD has an excellent electron drift channel inside, and this article also analyzes the electrical performance of the drift channel to verify the correctness of the design method of the L-SDD.

4.
Adv Sci (Weinh) ; 11(19): e2400966, 2024 May.
Article in English | MEDLINE | ID: mdl-38483027

ABSTRACT

Ionic memristors can emulate brain-like functions of biological synapses for neuromorphic technologies. Apart from the widely studied excitatory-excitatory and excitatory-inhibitory synapses, reports on memristors with the inhibitory-inhibitory synaptic behaviors remain a challenge. Here, the first biaxially inhibited artificial synapse is demonstrated, consisting of a solid electrolyte and conjugated microporous polymers bilayer as neurotransmitter, with the former serving as an ion reservoir and the latter acting as a confined transport. Due to the migration, trapping, and de-trapping of ions within the nanoslits, the device poses inhibitory synaptic plasticity under both positive and negative stimuli. Remarkably, the artificial synapse is able to maintain a low level of stable nonvolatile memory over a long period of time (≈60 min) after multiple stimuli, with feature-inferencing/-training capabilities of neural node in neuromorphic computing. This work paves a reliable strategy for constructing nanochannel ionic memristive materials toward fully inhibitory synaptic devices.


Subject(s)
Electrolytes , Neurotransmitter Agents , Synapses , Synapses/physiology , Electrolytes/chemistry , Porosity , Neuronal Plasticity/physiology
5.
Trials ; 25(1): 101, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38302990

ABSTRACT

BACKGROUND: Diet is among the most influential lifestyle factors impacting chronic disease risk. Nutrimetabolomics, the application of metabolomics to nutrition research, allows for the detection of food-specific compounds (FSCs) that can be used to connect dietary patterns, such as a Mediterranean-style (MED) diet, to health. This validation study is based upon analyses from a controlled feeding MED intervention, where our team identified FSCs from eight foods that can be detected in biospecimens after consumption and may therefore serve as food intake biomarkers. METHODS: Individuals with overweight/obesity who do not habitually consume a MED dietary pattern will complete a 16-week randomized, multi-intervention, semi-controlled feeding study of isocaloric dietary interventions: (1) MED-amplified dietary pattern, containing 500 kcal/day from eight MED target foods: avocado, basil, cherry, chickpea, oat, red bell pepper, walnut, and a protein source (alternating between salmon or unprocessed, lean beef), and (2) habitual/Western dietary pattern, containing 500 kcal/day from six non-MED target foods: cheesecake, chocolate frozen yogurt, refined grain bread, sour cream, white potato, and unprocessed, lean beef. After a 2-week washout, participants complete four, 4-week intervention periods, with biospecimen sampling and outcome assessments at baseline and at intervention weeks 4, 8, 12, and 16. The primary outcome is change in the relative abundance of FSCs from the eight MED target foods in participant biospecimens from baseline to the end of each intervention period. Secondary outcomes include mean change in cardiometabolic health indicators, inflammatory markers, and adipokines. Exploratory outcomes include change in diversity and community composition of the gut microbiota. DISCUSSION: Our stepwise strategy, beginning with identification of FSCs in whole diets and biospecimens, followed by relating these to health indicators will lead to improved methodology for assessment of dietary patterns and a better understanding of the relationship between food and health. This study will serve as a first step toward validating candidate food intake biomarkers and allow for assessment of relationships with cardiometabolic health. The identification of food intake biomarkers is critical to future research and has implications spanning health promotion and disease prevention for many chronic conditions. TRIAL REGISTRATION: Registered at ClinicalTrials.gov: NCT05500976 ; Date of registration: August 15, 2022.


Subject(s)
Cardiovascular Diseases , Diet, Mediterranean , Animals , Cattle , Humans , Dietary Patterns , Obesity/diagnosis , Obesity/prevention & control , Biomarkers , Cardiovascular Diseases/prevention & control , Randomized Controlled Trials as Topic
6.
J Nutr ; 154(1): 26-40, 2024 01.
Article in English | MEDLINE | ID: mdl-37918675

ABSTRACT

BACKGROUND: Nutrimetabolomics allows for the comprehensive analysis of foods and human biospecimens to identify biomarkers of intake and begin to probe their associations with health. Salmon contains hundreds of compounds that may provide cardiometabolic benefits. OBJECTIVES: We used untargeted metabolomics to identify salmon food-specific compounds (FSCs) and their predicted metabolites that were found in plasma after a salmon-containing Mediterranean-style (MED) diet intervention. Associations between changes in salmon FSCs and changes in cardiometabolic health indicators (CHIs) were also explored. METHODS: For this secondary analysis of a randomized, crossover, controlled feeding trial, 41 participants consumed MED diets with 2 servings of salmon per week for 2 5-wk periods. CHIs were assessed, and fasting plasma was collected pre- and postintervention. Plasma, salmon, and 99 MED foods were analyzed using liquid chromatography-mass spectrometry-based metabolomics. Compounds were characterized as salmon FSCs if detected in all salmon replicates but none of the other foods. Metabolites of salmon FSCs were predicted using machine learning. For salmon FSCs and metabolites found in plasma, linear mixed-effect models were used to assess change from pre- to postintervention and associations with changes in CHIs. RESULTS: Relative to the other 99 MED foods, there were 508 salmon FSCs with 237 unique metabolites. A total of 143 salmon FSCs and 106 metabolites were detected in plasma. Forty-eight salmon FSCs and 30 metabolites increased after the intervention (false discovery rate <0.05). Increases in 2 annotated salmon FSCs and 2 metabolites were associated with improvements in CHIs, including total cholesterol, low-density lipoprotein cholesterol, triglycerides, and apolipoprotein B. CONCLUSIONS: A data-driven nutrimetabolomics strategy identified salmon FSCs and their predicted metabolites that were detectable in plasma and changed after consumption of a salmon-containing MED diet. Findings support this approach for the discovery of compounds in foods that may serve, upon further validation, as biomarkers or act as bioactive components influential to health. The trials supporting this work were registered at NCT02573129 (Mediterranean-style diet intervention) and NCT05500976 (ongoing clinical trial).


Subject(s)
Cardiovascular Diseases , Diet, Mediterranean , Humans , Animals , Salmon , Seafood , Cholesterol , Biomarkers , Cardiovascular Diseases/prevention & control , Diet
7.
J Nutr ; 154(2): 574-582, 2024 02.
Article in English | MEDLINE | ID: mdl-38135005

ABSTRACT

BACKGROUND: Mushrooms are a nutritious food, though knowledge of the effects of mushroom consumption on cardiometabolic risk factors is limited and inconsistent. OBJECTIVE: We assessed the effects of consuming mushrooms as part of a healthy United States Mediterranean-style dietary pattern (MED) on traditional and emerging cardiometabolic disease (CMD) risk factors. We hypothesized that adopting a MED diet with mushrooms would lead to greater improvements in multiple CMD risk factors. METHODS: Using a randomized, parallel study design, 60 adults (36 females, 24 males; aged 46 ± 12 y; body mass index 28.3 ± 2.84 kg/m2, mean ± standard deviation) without diagnosed CMD morbidities consumed a MED diet (all foods provided) without (control with breadcrumbs) or with 84 g/d of Agaricus bisporus (White Button, 4 d/wk) and Pleurotus ostreatus (Oyster, 3 d/wk) mushrooms for 8 wk. Fasting baseline and postintervention outcome measurements were traditional CMD risk factors, including blood pressure and fasting serum lipids, lipoproteins, glucose, and insulin. Exploratory CMD-related outcomes included lipoprotein particle sizes and indexes of inflammation. RESULTS: Adopting the MED-mushroom diet compared with the MED-control diet without mushrooms improved fasting serum glucose (change from baseline -2.9 ± 1.18 compared with 0.6 ± 1.10 mg/dL; time × group P = 0.034). Adopting the MED diet, independent of mushroom consumption, reduced serum total cholesterol (-10.2 ± 3.77 mg/dL; time P = 0.0001). Concomitantly, there was a reduction in high-density lipoprotein (HDL) cholesterol, buoyant HDL2b, and apolipoprotein A1, and an increase in lipoprotein(a) concentrations (main effect of time P < 0.05 for all). There were no changes in other measured CMD risk factors. CONCLUSIONS: Consuming a Mediterranean-style healthy dietary pattern with 1 serving/d of whole Agaricus bisporus and Pleurotus ostreatus mushrooms improved fasting serum glucose but did not influence other established or emerging CMD risk factors among middle-aged and older adults classified as overweight or obese but with clinically normal cardiometabolic health. TRIAL REGISTRATION NUMBER: https://www. CLINICALTRIALS: gov/study/NCT04259229?term=NCT04259229&rank=1.


Subject(s)
Agaricus , Cardiovascular Diseases , Male , Female , Middle Aged , Humans , Aged , Dietary Patterns , Cardiometabolic Risk Factors , Cholesterol, HDL , Glucose , Cardiovascular Diseases/prevention & control
8.
Phys Rev Lett ; 131(22): 226802, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38101373

ABSTRACT

HfO_{2}-based ferroelectric thin films are promising for their application in ferroelectric devices. Predicting the ultimate magnitude of polarization and understanding its switching mechanism are critical to realize the optimal performance of these devices. Here, a generalized solid-state variable cell nudged elastic band method is employed to predict the switching pathway associated with domain-wall motion in (Hf,Zr)O_{2} ferroelectrics. It is found that the polarization reversal pathway, where threefold coordinated O atoms pass across the nominal unit-cell boundaries defined by the Hf/Zr atomic planes, is energetically more favorable than the conventional pathway where the O atoms do not pass through these planes. This finding implies that the polarization orientation in the orthorhombic Pca2_{1} phase of HfO_{2} and its derivatives is opposite to that normally assumed, predicts the spontaneous polarization magnitude of about 70 µC/cm^{2} that is nearly 50% larger than the commonly accepted value, signifies a positive intrinsic longitudinal piezoelectric coefficient, and suggests growth of ferroelectric domains, in response to an applied electric field, structurally reversed to those usually anticipated. These results provide important insights into the understanding of ferroelectricity in HfO_{2}-based ferroelectrics.

9.
J Mater Chem B ; 11(48): 11578-11587, 2023 12 13.
Article in English | MEDLINE | ID: mdl-38014941

ABSTRACT

Chronic wound healing remains challenging due to the oxidative microenvironment. Prussian blue (PB) nanoparticles exhibiting multiple antioxidant enzyme-like activities have attracted widespread attention, while their antioxidant efficacy remains unsatisfied. Herein, ultrasmall calcium-enriched Prussian blue nanoparticles (CaPB NPs) are simply constructed with high yields for the wound repair application. Owing to the ultrasmall size and synergistic effect of the generated dual active sites, the CaPB NPs exhibit prominent antioxidase-like activities, protecting cells from oxidative stress-induced damage. In addition to the effect of Ca on regulating keratinocyte and fibroblast growth, it has been demonstrated that the administration of CaPB NPs obviously promoted wound closure as well as collagen deposition and neovascularization in the full-thickness wound defect model in mice. Importantly, the CaPB NP treatment can effectively up-regulate the expression levels of anti-inflammatory cytokines and vascular endothelial growth factors to remodel the wound microenvironment, thereby accelerating the wound healing process. Overall, this work reveals that metal atom substitution is an effective strategy to construct ultrasmall and high-catalytic-performance PB-based nanozymes and further potentiate their effectiveness for chronic wound management.


Subject(s)
Antioxidants , Calcium , Mice , Animals , Calcium/pharmacology , Antioxidants/pharmacology , Wound Healing , Collagen/metabolism
10.
Foods ; 12(16)2023 Aug 08.
Article in English | MEDLINE | ID: mdl-37627983

ABSTRACT

Mushrooms contain multiple essential nutrients and health-promoting bioactive compounds, including the amino acid L-ergothioneine. Knowledge of the chemical composition of different mushroom varieties will aid research on their health-promoting properties. We compared the metabolomes of fresh raw white button, crimini, portabella, lion's mane, maitake, oyster, and shiitake mushrooms using untargeted liquid chromatography mass spectrometry (LC/MS)-based metabolomics. We also quantified amino acid concentrations, including L-ergothioneine, a potential antioxidant which is not synthesized by plants or animals. Among the seven mushroom varieties, more than 10,000 compounds were detected. Principal Component Analysis indicated mushrooms of the same species, Agaricus Bisporus (white button, portabella, crimini), group similarly. The other varieties formed individual, distinct clusters. A total of 1344 (520 annotated) compounds were detected in all seven mushroom varieties. Each variety had tens-to-hundreds of unique-to-mushroom-variety compounds. These ranged from 29 for crimini to 854 for lion's mane. All three Agaricus bisporus varieties had similar amino acid profiles (including detection of all nine essential amino acids), while other varieties had less methionine and tryptophan. Lion's mane and oyster mushrooms had the highest concentrations of L-ergothioneine. The detection of hundreds of unique-to-mushroom-variety compounds emphasizes the differences in chemical composition of these varieties of edible fungi.

11.
J Nutr ; 153(9): 2612-2621, 2023 09.
Article in English | MEDLINE | ID: mdl-37506974

ABSTRACT

BACKGROUND: Evidence regarding the effects of infant feeding type (exclusive breastfeeding compared with exclusive formula feeding) on the gut microbiota and how it impacts infant growth status is limited. OBJECTIVES: The primary objective was to compare gut microbiota by feeding type and characterize the associations between gut microbiota and infant growth status. METHODS: Stool samples from healthy, full-term infants (4-5 mo-old) who were either exclusively breastfed (BF) or exclusively formula-fed (FF) in Denver, CO, United States were collected, and fecal 16S ribosomal ribonucleic acid gene-based profiling was conducted. Length and weight were measured at the time of stool collection. Length-for-age z-score, weight-for-age z-scores (WAZ), and weight-for-length z-scores were calculated based on the World Health Organization standards. Associations between gut microbial taxa and anthropometric z-scores were assessed by Spearman's rank correlation test. RESULTS: A total of 115 infants (BF n = 54; FF n = 61) were included in this study. Feeding type (BF compared with FF) was the most significant tested variable on gut microbiota composition (P < 1 × 10-6), followed by mode of delivery and race. Significant differences were observed in α-diversity, ß-diversity, and relative abundances of individual taxa between BF and FF. BF infants had lower α-diversity than FF infants. Abundances of Bifidobacterium and Lactobacillus were greater in the breastfeeding group. FF infants had a higher relative abundance of unclassified Ruminococcaceae (P < 0.001), which was associated with a higher WAZ (P < 0.001) and length-for-age z-score (P < 0.01). Lactobacillus was inversely associated with WAZ (P < 0.05). CONCLUSIONS: Feeding type is the main driver of gut microbiota differences in young infants. The gut microbiota differences based on feeding type (exclusive breast- or formula feeding) were associated with observed differences in growth status. This trial was registered at clinicaltrials.gov as NCT02142647, NCT01693406, and NCT04137445.


Subject(s)
Breast Feeding , Gastrointestinal Microbiome , Female , Humans , Infant , Milk, Human , Infant Formula , Infant Nutritional Physiological Phenomena , Feces/microbiology
12.
J Nutr ; 153(5): 1439-1452, 2023 05.
Article in English | MEDLINE | ID: mdl-36921804

ABSTRACT

BACKGROUND: Limited research evidence exists on the effects of red meat on gut microbiota in human adults. OBJECTIVE: We aim to assess the effects of consuming a Healthy U.S.-Style Dietary Pattern (HDP), without or with unprocessed or processed lean red meats, on gut microbiota and fecal short-chain fatty acid (SCFA) levels in healthy young adults. Secondary outcomes are cardiovascular disease risk factors. METHODS: We conducted a randomized, controlled, crossover trial with 3 3-wk dietary interventions, each separated by a 5-wk washout period with habitual dietary intake. Nineteen participants (8 females, age 26 ± 4 y old, BMI 23 ± 3 kg/m2) consumed 3 study diets in random order: 1) healthy lacto-ovo vegetarian diet (LOV); 2) LOV plus 3 ounces/d of cooked unprocessed lean red meat (URM); and 3) LOV plus 3 ounces/d of cooked processed lean red meat (PRM). Fecal and fasting blood samples were collected before and during the last 2 wk of each intervention. We measured fecal bacterial community structure using 16S rRNA amplicon sequencing (V4 region, primers 515F-806R). Community diversity, structure, and taxonomic composition were computed using Mothur v.1.44.3. RESULTS: The addition of unprocessed or processed lean red meats to a LOV HDP did not influence short-term changes in bacterial taxonomic composition. Independent of red meat intake, the HDP led to changes in 23 bacteria; reductions in serum total cholesterol (TC) and LDL-C concentrations; but no changes in fecal SCFA, serum triglycerides, HDL-C concentrations, TC/HDL-C ratio, or blood pressures. With data from all 3 diet interventions combined, changes in some bacteria were associated with improvements in TC, LDL-C, triglycerides, and HDL-C concentrations, and TC/HDL-C ratio. CONCLUSIONS: Healthy young adults who adopt an HDP that may be vegetarian or omnivorous, including lean red meat, experience short-term changes in gut microbial composition, which associate with improvements in multiple lipid-related cardiovascular risk factors. NCT03885544, https://clinicaltrials.gov/ct2/show/NCT03885544?cond=NCT03885544&draw=2&rank=1.


Subject(s)
Cardiovascular Diseases , Gastrointestinal Microbiome , Red Meat , Female , Humans , Young Adult , Adult , Cardiovascular Diseases/prevention & control , Cholesterol, LDL , RNA, Ribosomal, 16S , Risk Factors , Diet , Triglycerides , Heart Disease Risk Factors , Vegetarians , Cross-Over Studies
13.
Adv Nutr ; 14(2): 215-237, 2023 03.
Article in English | MEDLINE | ID: mdl-36822879

ABSTRACT

Emerging research indicates the importance of gut microbiota in mediating the relationship between meat intake and human health outcomes. We aimed to assess the state of available scientific literature on meat intake and gut microbiota in humans (PROSPERO, International Prospective Register of Systematic Reviews, CRD42020135649). We first conducted a scoping review to identify observational and interventional studies on this topic. Searches were performed for English language articles using PubMed, Cochrane Library, Scopus, and CINAHL (Cumulated Index to Nursing and Allied Health Literature) databases from inception to August 2021 and using keywords related to meat (inclusive of mammalian, avian, and aquatic subtypes) and gut microbiota. Of 14,680 records, 85 eligible articles were included in the scoping review, comprising 57 observational and 28 interventional studies. One prospective observational study and 13 randomized controlled trials (RCTs) were identified in adults without diagnosed disease. We included the 13 RCTs, comprising 18 comparisons, in the systematic review to assess the effects of higher and lower intakes of total meat and meat subtypes on the gut microbiota composition. The bacterial composition was differentially affected by consuming diets with and without meat or with varied meat subtypes. For example, higher meat intake tended to decrease population sizes of genera Anerostipes and Faecalibacterium, but it increased the population size of Roseburia across studies. However, the magnitude and directionality of most microbial responses varied, with inconsistent patterns of responses across studies. The data were insufficient for comparison within or between meat subtypes. The paucity of research, especially among meat subtypes, and heterogeneity of findings underscore the need for more well-designed prospective studies and full-feeding RCTs to address the relationships between and effects of consuming total meat and meat subtypes on gut microbiota, respectively.


Subject(s)
Gastrointestinal Microbiome , Adult , Animals , Humans , Diet , Mammals , Meat , Observational Studies as Topic , Randomized Controlled Trials as Topic
14.
Emerg Med Int ; 2022: 3228023, 2022.
Article in English | MEDLINE | ID: mdl-36406933

ABSTRACT

Objective: To investigate the application effect of 24 h dynamic electrocardiogram in the diagnosis of asymptomatic myocardial ischemia with arrhythmia in elderly patients with coronary heart disease. Methods: A total of 206 elderly patients suspected of coronary heart disease (CHD) with asymptomatic myocardial ischemia and arrhythmia were selected as the research subjects. 24 h dynamic electrocardiogram and conventional electrocardiogram examinations were conducted. Coronary angiography was used as the gold standard to observe the performance of the two examination methods in the diagnosis of asymptomatic myocardial ischemia with arrhythmia in elderly patients with CHD. Results: Coronary angiography showed 174 positive cases and 32 negative cases among the 206 patients. The diagnostic results of a conventional electrocardiogram showed 150 positive cases and 20 negative cases. Its sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 86.21%, 62.50%, 82.52%, 92.59%, and 45.45%, respectively. The diagnostic results of 24 h dynamic electrocardiograms showed 168 positive cases and 29 negative cases. Its sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 96.55%, 96.63%, 95.63%, 98.25%, and 82.86%, respectively. The above results indicated that 24 h dynamic electrocardiogram was significantly better (P < 0.05). The detection rate of arrhythmia types by 24-hour dynamic electrocardiogram was significantly higher than that of conventional electrocardiogram (P < 0.05). Conclusion: 24 h dynamic electrocardiogram is helpful for the diagnosis of asymptomatic myocardial ischemia with arrhythmia in elderly patients with CHD and can improve the detection rate, thereby providing a basis for clinical diagnosis and treatment.

15.
Front Microbiol ; 13: 823757, 2022.
Article in English | MEDLINE | ID: mdl-35979501

ABSTRACT

Objective: To characterize the changes in gut microbiota during pregnancy and determine the effects of nutritional intervention on gut microbiota in women from sub-Saharan Africa (the Democratic Republic of the Congo, DRC), South Asia (India and Pakistan), and Central America (Guatemala). Methods: Pregnant women in the Women First (WF) Preconception Maternal Nutrition Trial were included in this analysis. Participants were randomized to receive a lipid-based micronutrient supplement either ≥3 months before pregnancy (Arm 1); started the same intervention late in the first trimester (Arm 2); or received no nutrition supplements besides those self-administered or prescribed through local health services (Arm 3). Stool and blood samples were collected during the first and third trimesters. Findings presented here include fecal 16S rRNA gene-based profiling and systemic and intestinal inflammatory biomarkers, including alpha (1)-acid glycoprotein (AGP), C-reactive protein (CRP), fecal myeloperoxidase (MPO), and calprotectin. Results: Stool samples were collected from 640 women (DRC, n = 157; India, n = 102; Guatemala, n = 276; and Pakistan, n = 105). Gut microbial community structure did not differ by intervention arm but changed significantly during pregnancy. Richness, a measure of alpha-diversity, decreased over pregnancy. Community composition (beta-diversity) also showed a significant change from first to third trimester in all four sites. Of the top 10 most abundant genera, unclassified Lachnospiraceae significantly decreased in Guatemala and unclassified Ruminococcaceae significantly decreased in Guatemala and DRC. The change in the overall community structure at the genus level was associated with a decrease in the abundances of certain genera with low heterogeneity among the four sites. Intervention arms were not significantly associated with inflammatory biomarkers at 12 or 34 weeks. AGP significantly decreased from 12 to 34 weeks of pregnancy, whereas CRP, MPO, and calprotectin did not significantly change over time. None of these biomarkers were significantly associated with the gut microbiota diversity. Conclusion: The longitudinal reduction of individual genera (both commensals and potential pathogens) and alpha-diversity among all sites were consistent and suggested that the effect of pregnancy on the maternal microbiota overrides other influencing factors, such as nutrition intervention, geographical location, diet, race, and other demographical variables.

16.
Nanomaterials (Basel) ; 12(13)2022 Jun 28.
Article in English | MEDLINE | ID: mdl-35808058

ABSTRACT

In-sensor computing can simultaneously output image information and recognition results through in-situ visual signal processing, which can greatly improve the efficiency of machine vision. However, in-sensor computing is challenging due to the requirement to controllably adjust the sensor's photosensitivity. Herein, it is demonstrated a ternary cationic halide Cs0.05FA0.81MA0.14 Pb(I0.85Br0.15)3 (CsFAMA) perovskite, whose External quantum efficiency (EQE) value is above 80% in the entire visible region (400-750 nm), and peak responsibility value at 750 nm reaches 0.45 A/W. In addition, the device can achieve a 50-fold enhancement of the photoresponsibility under the same illumination by adjusting the internal ion migration and readout voltage. A proof-of-concept visually enhanced neural network system is demonstrated through the switchable photosensitivity of the perovskite sensor array, which can simultaneously optimize imaging and recognition results and improve object recognition accuracy by 17% in low-light environments.

17.
Se Pu ; 40(4): 391-398, 2022 Apr.
Article in Chinese | MEDLINE | ID: mdl-35362687

ABSTRACT

Capillary electrochromatography for enantioseparation has received considerable research attention in the past decades, because it integrates the advantages of classical electrophoresis and modern micro-column separation. Chirality is a fundamental feature of compounds found in nature and is also a major concern in the modern pharmaceutical industry. Porous organic cages (POCs) are defined as a class of porous materials with permanent ordered three-dimensional cavity structures that are different from those of porous materials, such as zeolite, metal-organic frameworks, covalent organic frameworks, and mesoporous silica. POCs have good solubility in general organic solvents and can be used as a chromatographic stationary phase conveniently coated inside a standard capillary column. Homochiral POCs with hydroxyl groups on the cage molecules were synthesized by imine-linked condensation of 2-hydroxy-1,3,5-triformylbenzene with (1R,2R)-1,2-diphenylethylenediamine. The thus-synthesized POCs were characterized by nuclear magnetic resonance (NMR) spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRD) analysis, etc. In the FT-IR spectra, the absorption peaks at 1602, 1489, and 1458 cm-1 were attributed to the C=C-H and C=C tensile vibrations in the benzene ring. The strong characteristic absorption peak at 1636 cm-1 was attributed to the imine bond (C=N) stretching, the two peaks at about 2900 cm-1 were attributed to C-H bond vibration, and the absorption peak at 3420 cm-1 was attributed to the O-H pulling vibration. In the XRD patterns, the powder diffraction peaks of the POCs were consistent with the simulated data. These results indicated that POCs were successfully synthesized. Thermogravimetric analysis was performed in the temperature range of 25-800 ℃ (10 ℃/min), and the POCs were found to be stable up to 380 ℃. Dichloromethane was used as solvent to uniformly coat POCs on the capillary wall to prepare an electrochromatography column. Joule heat generated in electrophoresis was negligible under the experiment condition used for the open-tubular column. Four chiral compounds, viz. dihydroflavone, praziquantel, naproxen, and 3,5-dinitro-N-(1-phenylethyl)benzamide, were used as test compounds, and the electrochromatography separation conditions were optimized such that the best separations were obtained. The voltage was applied to separate the selected enantiomers in the range of 10-20 kV. Considering the good separation and appropriate migration time simultaneously, applied voltages of 13 kV and 12 kV were recommended for dihydroflavones and 3,5-dinitro-N-(1-phenylethyl)benzamide, respectively, as well as 14 kV for praziquantel and naproxen. The concentration of the buffer solution for dihydroflavonoids was 0.075 mol/L, and those for praziquantel, naproxen, and 3,5-dinitro-N-(1-phenylethyl)benzamide were 0.100 mol/L. The pH was 3.51 for all four substances. Resolutions of 2.99, 2.10, 2.58, and 3.59 were achieved on a POC chiral column for dihydroflavonoids, praziquantel, naproxen, and 3,5-dinitro-N-(1-phenylethyl)benzamide, respectively. Two positional isomers, viz. o,m,p-nitrophenol and o,m,p-nitrophenilamine, were also successfully separated with 0.100 mol/L Tris-H3PO4 at pH 3.51. Therefore, the chiral electrochromatography column showed good chiral recognition ability and the POC is an excellent separation material with excellent application prospect in chiral electrochromatography.


Subject(s)
Capillary Electrochromatography , Capillary Electrochromatography/methods , Porosity , Silicon Dioxide/chemistry , Spectroscopy, Fourier Transform Infrared , Stereoisomerism
18.
Nanomaterials (Basel) ; 12(4)2022 Feb 11.
Article in English | MEDLINE | ID: mdl-35214939

ABSTRACT

Nanowire structures with high-density interfaces are considered to have higher radiation damage resistance properties compared to conventional bulk structures. In the present work, molecular dynamics (MD) is conducted to investigate the irradiation effects and mechanical response changes of GaAs nanowires (NWs) under heavy-ion irradiation. For this simulation, single-ion damage and high-dose ion injection are used to reveal defect generation and accumulation mechanisms. The presence of surface effects gives an advantage to defects in rapid accumulation but is also the main cause of dynamic annihilation of the surface. Overall, the defects exhibit a particular mechanism of rapid accumulation to saturation. Moreover, for the structural transformation of irradiated GaAs NWs, amorphization is the main mode. The main damage mechanism of NWs is sputtering, which also leads to erosion refinement at high doses. The high flux ions lead to a softening of the mechanical properties, which can be reflected by a reduction in yield strength and Young's modulus.

19.
Front Nutr ; 9: 1063518, 2022.
Article in English | MEDLINE | ID: mdl-36778973

ABSTRACT

Objective: This project aimed to evaluate the impact of meat- vs. dairy-based complementary foods on gut microbiota and whether it relates to growth. Design: Full-term, formula-fed infants were recruited from the metro Denver area (Colorado, US) and randomized to a meat- or dairy-based complementary diet from 5 to 12 months of age. Infant's length and weight were measured, and stool samples were collected at 5, 10, and 12 months for 16S rRNA gene sequencing and short-chain fatty acids (SCFAs) quantification. Results: Sixty-four infants completed the dietary intervention (n = 32/group). Weight-for-age Z (WAZ) scores increased in both groups and length-for-age Z scores (LAZ) increased in the meat group only, which led to a significant group-by-time interaction (P = 0.02) of weight-for-length Z (WLZ) score. Microbiota composition (Beta-diversity) differed between groups at 12 months (weighted PERMANOVA P = 0.01) and had a group-by-time interaction of P = 0.09. Microbial community richness (Chao1) increased in the meat group only. Genus Akkermansia had a significant group-by-time interaction and increased in the dairy group and decreased in the meat group. A significant fold change of butyric acid from 5 to 12 months was found in the meat group (+1.75, P = 0.011) but not in the dairy group. Regression analysis showed that Chao1 had a negative association with WLZ and WAZ. Several genera also had significant associations with all growth Z scores. Conclusion: Complementary feeding not only impacts infant growth but also affects gut microbiota maturation. Complementary food choices can affect both the gut microbiota diversity and structures and these changes in gut microbiota are associated with infant growth.

20.
Metabolites ; 11(4)2021 Apr 14.
Article in English | MEDLINE | ID: mdl-33919953

ABSTRACT

Identifying and annotating the molecular composition of individual foods will improve scientific understanding of how foods impact human health and how much variation exists in the molecular composition of foods of the same species. The complexity of this task includes distinct varieties and variations in natural occurring pigments of foods. Lipidomics, a sub-field of metabolomics, has emerged as an effective tool to help decipher the molecular composition of foods. For this proof-of-principle research, we determined the lipidomic profiles of green, yellow and red bell peppers (Capsicum annuum) using liquid chromatography mass spectrometry and a novel tool for automated annotation of compounds following database searches. Among 23 samples analyzed from 6 peppers (2 green, 1 yellow, and 3 red), over 8000 lipid compounds were detected with 315 compounds (106 annotated) found in all three colors. Assessments of relationships between these compounds and pepper color, using linear mixed effects regression and false discovery rate (<0.05) statistical adjustment, revealed 11 compounds differing by color. The compound most strongly associated with color was the carotenoid, ß-cryptoxanthin (p-value = 7.4 × 10-5; FDR adjusted p-value = 0.0080). These results support lipidomics as a viable analytical technique to identify molecular compounds that can be used for unique characterization of foods.

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