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1.
Diabetes Care ; 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39383121

ABSTRACT

OBJECTIVE: Certain foods characterizing the alternate Mediterranean diet (aMED) are high in persistent organic pollutants (POPs), which are related to greater gestational diabetes mellitus (GDM) risk. We examined the associations of combined aMED and POP exposure with GDM. RESEARCH DESIGN AND METHODS: aMED score of 1,572 pregnant women was derived from food frequency questionnaires at early pregnancy within the U.S. Fetal Growth Study and plasma concentrations of 76 POPs, including organochlorine pesticides, polybrominated diphenyl ethers, polychlorinated biphenyls (PCBs), and per- and polyfluoroalkyl substances, were measured. Associations of combined aMED score and exposure to POPs with GDM risk were examined by multivariable logistic regression models. RESULTS: In 61 of 1,572 (3.88%) women with GDM, 25 of 53 included POPs had a detection rate >50%. Higher POP levels appeared to diminish potential beneficial associations of aMED score with GDM risk, with the lowest GDM risk observed among women with both high aMED score and low POP concentrations. Specifically, adjusted log-odds ratios of GDM risk comparing women with low PCB and high aMED score with those with low aMED score and high PCB concentrations was -0.74 (95% CI -1.41, -0.07). Inverse associations were also observed among women with low aMED score and high TransNo_chlor, PCB182_187, PCB196_203, PCB199, and PCB206. These associations were more pronounced among women with overweight or obesity. CONCLUSIONS: Pregnant women who consumed a healthy Mediterranean diet but had a low exposure to POP concentrations had the lowest GDM risk. Future endeavors to promote a healthy diet to prevent GDM may consider concurrent POP exposure.

2.
Plant Physiol Biochem ; 216: 109165, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39342661

ABSTRACT

Silica nanoparticles (SiNPs) and brassinolide (BR) have been used as nano-fertilizer and growth regulator, respectively to enhance crop tolerance to abiotic stress. However, it is unclear whether a combination of the two (BR + SiNPs) is more beneficial than single application of BR or SiNPs to improve the growth of deficit-irrigated sugar beets. In this study, a two-year (2022-2023) field experiment was conducted to investigate the effects of foliar spraying of water (CK), SiNPs, BR, and BR + SiNPs on the antioxidant defense, photosynthetic capacity, dry matter accumulation, nutrient uptake, and yield of sugar beets under full irrigation (100% of crop evapotranspiration (ETc), W1) and deficit irrigation (60% ETc, W2). The results showed that compared with the application of BR or SiNPs, the application of BR + SiNPs could enhance the antioxidant defense, osmoregulation, and photosynthesis of the full-irrigated and deficit-irrigated sugar beet leaves, and ultimately improved the water status, growth, and yield of sugar beet plants. There was no significant difference in the net revenue (NR) between BR + SiNPs treatment and CK under W1 conditions. However, the NR of the BR + SiNPs treatment increased by 27.0% (p < 0.05) compared with that of CK under W2 conditions, and there was no significant difference in NR between BR + SiNPs and SiNPs treatments. A comprehensive evaluation using entropy weight combined with technique for order preference by similarity to ideal solution method found that under deficit irrigation condition, spraying SiNPs could improve the growth of sugar beet, increase the TY, NR, and water use efficiency, and reduce costs compared with spraying BR + SiNPs. Therefore, foliar spraying of SiNP on deficit-irrigated sugar beets can be used to improve sugar beet growth and reduce the potential economic losses caused by deficit irrigation.

3.
Nutr J ; 23(1): 110, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39304916

ABSTRACT

BACKGROUND: Maternal feeding practices play a major role in children's dietary intakes. However, there is limited data on the associations between trajectories of dietary patterns (DPs) and patterns of maternal feeding practices during early childhood. METHODS: Using data from a multi-ethnic Asian cohort study, namely the Growing Up in Singapore Towards healthy Outcomes (GUSTO), dietary intakes were measured using Food Frequency Questionnaires in children at 18 months, 5 and 7 years of age. Maternal feeding practices were assessed using validated questionnaires at 15 months, 3 and 5 years of age. Principal component analysis was used to derive 2 major DPs at all time-points as well as patterns of maternal feeding practices. Group-based trajectory modelling was used to identify trajectory groups for the derived DPs. Multivariable logistic regression examined associations between patterns of maternal feeding practices and DP trajectory groups. RESULTS: Two DPs, namely the 'healthy' and 'less healthy' were consistently derived at 18 months, 5 and 7 years of age. From each DP, 2 stable DP trajectory groups were further identified between 18 months and 7 years of age. For the 'healthy' DP trajectory, majority of the children (Group 1) formed a consistent average adherence trajectory group (91.8%) while the remaining children (Group 2) showed a higher but decreasing adherence (8.2%) to this DP. For the 'less healthy' DP trajectory, most children (Group 1) formed a consistent average adherence trajectory (95.5%), while the remainder (Group 2) showed consistent higher adherence to this 'less healthy' DP (4.5%). Two patterns of maternal feeding practices were derived and labelled as 'structured with autonomy support' and 'coercive control', respectively, at ages 15 months, 3 and 5 years. Children whose mothers showed high adherence to the structured with autonomy support feeding practices at age 5 years were significantly more likely to be associated with the higher but decreasing 'healthy' DP trajectory group [OR = 3.62 (95% CI: 1.64, 7.99)]. CONCLUSIONS: A small number of children in this multi-ethnic study showed high adherence to the 'healthy' or 'less healthy' DP trajectory groups, respectively, while the majority showed average adherence to either of these trajectories. The positive association between structured with autonomy support maternal feeding practices and higher z-scores for the healthy DP trajectory highlights the importance of guiding parents on appropriate feeding practices.


Subject(s)
Diet , Feeding Behavior , Adult , Child , Child, Preschool , Female , Humans , Infant , Male , Asian People/statistics & numerical data , Cohort Studies , Diet/statistics & numerical data , Diet/methods , Ethnicity/statistics & numerical data , Mothers/statistics & numerical data , Singapore , Surveys and Questionnaires
4.
Early Hum Dev ; 198: 106110, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39260074

ABSTRACT

BACKGROUND: The cognitive benefits of breastfeeding are widely recognized; however, its effects on brain development and later academic skills require further examination. This study aimed to examine the longitudinal relations between breastmilk feeding, neurophysiological changes, and early academic skills. METHODS: In the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort, breastmilk feeding practices were collected every 3 months from 3 weeks to 18 months postpartum. Resting electroencephalography (EEG) was recorded at 18 months and power spectral density was derived. The outcomes were a set of early academic assessments administered at age 4 (n = 810). Structural equation modelling was used to investigate EEG power as a mediator between breastmilk duration and early academic skills. RESULTS: Breastmilk feeding for ≥12 months was associated with better general knowledge, numeracy, and language at age 4 compared to shorter durations of breastmilk feeding (Cohen's d: 1.53-17.44). Linear regression showed that breastmilk duration was negatively and positively associated with low- (i.e., delta, theta) and high-frequency power (i.e., gamma), respectively (Cohen's f2: 0.03-0.09). After adjusting for demographic and child baseline covariates, a decrease in absolute and relative delta, as well as relative theta was associated with better general knowledge and numeracy (Cohen's f2: 0.16-0.25). Relative delta power provided an indirect path between breastmilk duration and early academic skills (x2: 18.390, p = 0.010; CFI: 0.978; TLI: 0.954; RMSEA: 0.040). CONCLUSIONS: Extended breastmilk feeding is associated with reduced low-frequency power and better early academic skills, suggesting benefits to brain development. Additional research to confirm this finding is warranted.

5.
Cell Rep Med ; 5(8): 101665, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39168101

ABSTRACT

Mesenchymal stromal cell (MSC) senescence is a key factor in skeletal aging, affecting the potential of MSC applications. Identifying targets to prevent MSC and skeletal senescence is crucial. Here, we report increased miR-29 expression in bone tissues of aged mice, osteoporotic patients, and senescent MSCs. Genetic overexpression of miR-29 in Prx1-positive MSCs significantly accelerates skeletal senescence, reducing cortical bone thickness and trabecular bone mass, while increasing femur cross-sectional area, bone marrow adiposity, p53, and senescence-associated secretory phenotype (SASP) levels. Mechanistically, miR-29 promotes senescence by upregulating p53 via targeting Kindlin-2 mRNA. miR-29 knockdown in BMSCs impedes skeletal senescence, enhances bone mass, and accelerates calvarial defect regeneration, also reducing lipopolysaccharide (LPS)-induced organ injuries and mortality. Thus, our findings underscore miR-29 as a promising therapeutic target for senescence-related skeletal diseases and acute inflammation-induced organ damage.


Subject(s)
Cellular Senescence , Mesenchymal Stem Cells , MicroRNAs , Animals , Female , Humans , Male , Mice , Aging , Bone and Bones/metabolism , Bone and Bones/pathology , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Lipopolysaccharides/pharmacology , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells/metabolism , Mice, Inbred C57BL , MicroRNAs/genetics , MicroRNAs/metabolism , Osteoporosis/genetics , Osteoporosis/pathology , Osteoporosis/therapy , Osteoporosis/metabolism , Senescence-Associated Secretory Phenotype/genetics , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics
6.
Cell Stem Cell ; 31(10): 1501-1512.e8, 2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39208804

ABSTRACT

Brain organoids with nucleus-specific identities provide unique platforms for studying human brain development and diseases at a finer resolution. Despite its essential role in vital body functions, the medulla of the hindbrain has seen a lack of in vitro models, let alone models resembling specific medullary nuclei, including the crucial spinal trigeminal nucleus (SpV) that relays peripheral sensory signals to the thalamus. Here, we report a method to differentiate human pluripotent stem cells into region-specific brain organoids resembling the dorsal domain of the medullary hindbrain. Importantly, organoids specifically recapitulated the development of the SpV derived from the dorsal medulla. We also developed an organoid system to create the trigeminothalamic projections between the SpV and the thalamus by fusing these organoids, namely human medullary SpV-like organoids (hmSpVOs), with organoids representing the thalamus (hThOs). Our study provides a platform for understanding SpV development, nucleus-based circuit organization, and related disorders in the human brain.


Subject(s)
Organoids , Trigeminal Nucleus, Spinal , Organoids/cytology , Humans , Trigeminal Nucleus, Spinal/cytology , Cell Differentiation , Brain/cytology , Pluripotent Stem Cells/cytology , Medulla Oblongata/cytology , Animals
7.
Angew Chem Int Ed Engl ; : e202412815, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39117561

ABSTRACT

Near-infrared (NIR) emitting phosphors draw much attention because they show great applicability and development prospects in many fields. Herein, a series of inverse spinel-type structured LiGa5O8 phosphors with a high concentration of Cr3+ activators is reported with a dual emission band covering NIR-I and II regions. Except for strong ionic exchange interactions such as Cr3+-Cr3+ and Cr3+ clusters, an intervalence charge transfer (IVCT) process between aggregated Cr ion pairs is proposed as the mechanism for the ~1210 nm NIR-II emission. Comprehensive structural and luminescence characterization points to IVCT between two Cr3+ being induced by structural distortion and further enhanced by irradiation. Construction of the configurational energy level diagram enabled elucidation of this transition within the IVCT process. Therefore, this work provides insight into the emission mechanism within the high Cr3+ concentration system, revealing a new design strategy for NIR-II emitting phosphors to promote its response.

8.
J Clin Hypertens (Greenwich) ; 26(10): 1181-1187, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39185609

ABSTRACT

Preeclampsia (PE) is a severe pregnancy complication characterized by significant alterations in coagulation function. This study aims to analyze the correlation between coagulation function, platelet parameters, and pregnancy outcomes in PE patients. Clinical data, along with blood and urine samples, were collected from 168 PE patients and 128 healthy pregnant women. General demographic and laboratory testing data were recorded, and maternal and fetal outcomes were followed up. Data were analyzed using Kaplan-Meier and logistic regression analyses. In mild PE patients, thrombin time (p = .000), platelet distribution width (PDW) (p = .000), and clot formation time (p = .000) were increased, while prothrombin time (p = .000) and fibrinogen (p = .045) were reduced. With increasing PE severity, prothrombin time (p = .000), platelet count (PLT) (p = .000), mean platelet volume (MPV) (p = .000), plateletcrit (p = .000), maximum amplitude (MA) (p = .000), and coagulation index (p = .001) decreased, whereas activated partial thromboplastin time (APTT) (p = .000), thrombin time (p = .002), D-dimer (p = .026), and PDW (p = .000) increased. Lower prothrombin time (p = .048), PLT (p = .004), and coagulation index (p = .026) or higher APTT (p = .032), thrombin time (p = .044), D-dimer (p = .023), and PDW (p = .016) were associated with a higher risk of poor pregnancy outcomes. Thrombin time was identified as an independent risk factor (p = .025, OR = 2.918, 95% CI: 1.145-7.436), whereas gestational age was an independent protective factor (p = .000, OR = 0.244, 95% CI: 0.151-0.395). This study demonstrates that specific coagulation and platelet parameters are significantly associated with PE severity and adverse pregnancy outcomes. These findings highlight the importance of monitoring coagulation function in PE patients to improve clinical management and outcomes.


Subject(s)
Blood Coagulation , Pre-Eclampsia , Pregnancy Outcome , Humans , Pregnancy , Female , Pre-Eclampsia/blood , Pre-Eclampsia/physiopathology , Pre-Eclampsia/diagnosis , Adult , Pregnancy Outcome/epidemiology , Blood Coagulation/physiology , Platelet Count/methods , Blood Platelets/physiology , Blood Coagulation Tests/methods , Prothrombin Time , Thrombin Time , Partial Thromboplastin Time , Mean Platelet Volume/methods , Fibrinogen/analysis , Fibrinogen/metabolism , Case-Control Studies , Fibrin Fibrinogen Degradation Products/analysis , Fibrin Fibrinogen Degradation Products/metabolism
9.
Yi Chuan ; 46(8): 627-639, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39140143

ABSTRACT

Heterosis is the phenomenon that the hybrid offspring outperform two-parent population. Hybridisation has been widely used in plant and animal production as it effectively improves the growth and developmental performance, reproductive performance and disease resistance of the offspring. Hybridization can effectively improve the growth and development performance, reproductive performance and disease resistance of offspring, so it is widely used in animal and plant production. Researchers have used cross-breeding techniques to cultivate excellent new agricultural and animal husbandry strains and supporting lines such as super-excellent Chaoyou 1000 hybrid rice, Xiaoyan No.6 hybrid wheat, Dumeng sheep, and Shanxia black pigs. However, there are still some urgent problems in the current hybrid dominance research: the existing hybrid dominance theory can only partially explain the phenomenon of plant and animal hybrid dominance, and the theory of animal hybrid dominance is less researched, and the accuracy of the existing hybrid dominance prediction methods is limited. China is the world's largest pork production and consumption country. Heterosis can effectively improve the production performance of pigs, and its application in the pig industry has important economic and research value. However, the existing research on pig hybrid production is in its infancy and needs to be further studied. In this review, we summarize the existing heterosis theory, heterosis prediction methods, and their application in pig production, to provide a reference for the application of heterosis in pig breeding.


Subject(s)
Hybrid Vigor , Animals , Swine/genetics , Hybridization, Genetic , Animal Husbandry/methods , Breeding/methods
10.
Diabetes Care ; 47(9): 1593-1596, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38968411

ABSTRACT

OBJECTIVE: To investigate associations of plasma glycated albumin (GA) concentrations in early and midpregnancy with gestational diabetes mellitus (GDM) risk. RESEARCH DESIGN AND METHODS: We measured GA concentrations using blood samples collected at 10-14 and 15-26 weeks' gestation in 107 GDM case and 214 control participants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Fetal Growth Study. We performed generalized linear mixed-effect regression to test the mean GA difference between GDM case and control participants and conditional logistic regression to assess prospective associations between GA concentrations and GDM risk. RESULTS: At 15-26 weeks' gestation mean GA was lower in GDM case participants than in control participants (mean 11.90% [95% CI 6.42-32.76] vs. 12.46% [8.45-38.35], adjusted P value for difference = 0.004). Consistently, women with higher GA concentrations tended to have a lower GDM risk, although the associations were not statistically significant. CONCLUSIONS: This study suggests that GA concentrations in midpregnancy might be lower in women who later develop GDM. Further studies are needed to identify the mechanism.


Subject(s)
Diabetes, Gestational , Glycated Serum Albumin , Glycation End Products, Advanced , Serum Albumin , Humans , Diabetes, Gestational/blood , Female , Pregnancy , Glycation End Products, Advanced/blood , Prospective Studies , Adult , Longitudinal Studies , Serum Albumin/analysis , Serum Albumin/metabolism
11.
Nat Food ; 5(7): 563-568, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38951691

ABSTRACT

Healthy dietary patterns, such as the alternate Mediterranean diet and alternate Healthy Eating Index, benefit cardiometabolic health. However, several food components of these dietary patterns are primary sources of environmental chemicals. Here, using data from a racially and ethnically diverse US cohort, we show that healthy dietary pattern scores were positively associated with plasma chemical exposure in pregnancy, particularly for the alternate Mediterranean diet and alternate Healthy Eating Index with polychlorinated biphenyls and per- and poly-fluoroalkyl substances. The associations appeared stronger among Asian and Pacific Islanders. These findings suggest that optimizing the benefits of a healthy diet requires concerted regulatory efforts aimed at lowering environmental chemical exposure.


Subject(s)
Environmental Exposure , Environmental Pollutants , Polychlorinated Biphenyls , Humans , Female , Pregnancy , Adult , Environmental Pollutants/blood , Environmental Exposure/adverse effects , Cohort Studies , Polychlorinated Biphenyls/blood , Diet, Healthy , Diet, Mediterranean , United States/epidemiology , Young Adult , Dietary Patterns
12.
Chemosphere ; 363: 142746, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38969223

ABSTRACT

Vanadate-based photocatalysts have recently attracted substantial attention owing to their outstanding photocatalytic activity for degrading organic pollutants and generating energy via photocatalytic processes. However, the relatively high price of vanadium has hindered the development of vanadate-based photocatalysts for various applications. Spent catalysts obtained from oil refineries typically contain a significant quantity of vanadium, making them valuable for recovery and utilization as precursors for the production of high-value-added photocatalysts. In this study, we transformed the V present in spent catalysts produced by the petrochemical industry into ternary vanadate-based photocatalysts [BiVO4/InVO4/Ag3VO4 (BVO/IVO/AVO, respectively)] designed for water remediation. The ternary composites revealed an enhanced photocatalytic capability, which was 1.42 and 5.1 times higher than those of the binary BVO/IVO and pristine AVO due to the facilitated charge separation. The ternary photocatalysts not only effectively treated wastewater containing various organic dyes, such as methylene blue (MB), rhodamine 6G (R6G), and brilliant green (BG), but also exhibited remarkable photocatalytic performance in the degradation of antibiotics, reduction of Cr(VI), and bacterial inactivation. This paper proposes a feasible route for recycling industrial waste as a source of vanadium to produce highly efficient vanadate-based photocatalysts.


Subject(s)
Bismuth , Vanadates , Vanadium , Water Pollutants, Chemical , Water Purification , Catalysis , Vanadates/chemistry , Water Pollutants, Chemical/chemistry , Vanadium/chemistry , Water Purification/methods , Bismuth/chemistry , Coloring Agents/chemistry , Wastewater/chemistry , Photochemical Processes
13.
Sheng Wu Gong Cheng Xue Bao ; 40(7): 2120-2135, 2024 Jul 25.
Article in Chinese | MEDLINE | ID: mdl-39044579

ABSTRACT

Antibiotics as emerging pollutants are frequently detected in surface water, raising concerns about the associated risk of antibiotic resistance genes (ARGs). Despite the widespread apprehension, there are still research gaps in the occurrence of antibiotic pollution in surface water and the associated ecological risks to aquatic organisms in China. Here, we established a dataset of antibiotic pollution in surface water in China during 2018-2022, which encompassed 3 368 concentration values of 128 antibiotics reported in 124 articles. Our analysis showed that antibiotic concentrations were predominantly in the ng/L-µg/L range, reaching up to 26 µg/L. Notably, sulfonamides (e.g., sulfamethoxazole) and quinolones (e.g., ciprofloxacin) were frequently reported at high concentrations. The pollution degree of antibiotics represented by sulfamethoxazole, ciprofloxacin, roxithromycin, and tetracycline exhibited no significant variation across different years but was lower in summer than that in spring and autumn. Additionally, distinct spatial distribution characteristics of the pollution were observed. According to calculation results of the aquatic ecological risk assessment model and the weighted frequency, we proposed a list of priority antibiotics including clarithromycin, erythromycin, sulfamethoxazole, ofloxacin, and oxytetracycline in surface water. Last but not least, this study points out the deficiencies in current research on the occurrence and ecological risks of antibiotics in surface water of China and provides viable screening strategies and monitoring recommendations in this context.


Subject(s)
Anti-Bacterial Agents , Water Pollutants, Chemical , China , Water Pollutants, Chemical/analysis , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/analysis , Risk Assessment , Environmental Monitoring , Sulfamethoxazole/analysis , Fresh Water , Ciprofloxacin/analysis , Seasons , Erythromycin/analysis , Clarithromycin/adverse effects , Drug Resistance, Microbial/genetics , Sulfonamides/analysis , Oxytetracycline/analysis
14.
Biosens Bioelectron ; 263: 116558, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39029277

ABSTRACT

Organophosphorus compounds are widely distributed and highly toxic to the environment and living organisms. The current detection of organophosphorus compounds is based on a single-mode method, which makes it challenging to achieve good portability, accuracy, and sensitivity simultaneously. This study designed a multifunctional microfluidic chip to develop a dual-mode biosensor employing a DNA hydrogel as a carrier and aptamers as recognition probes for the colorimetric/electrochemical detection of malathion, an organophosphorus compound. The biosensor balanced portability and stability by combining a microfluidic chip and target-triggered DNA hydrogel-sensing technologies. Moreover, the biosensor based on target-triggered DNA hydrogel modified microfluidic developed in this study exhibited a dual-mode response to malathion, providing both colorimetric and electrochemical signals. The colorimetric mode enables rapid visualization and qualitative detection and, when combined with a smartphone, allows on-site quantitative analysis with a detection limit of 56 nM. The electrochemical mode offers a broad linear range (0.01-3000 µM) and high sensitivity (a limit of detection of 5 nM). The two modes could validate each other and improve the accuracy of detection. The colorimetric/electrochemical dual-mode biosensor based on target-triggered DNA hydrogel modified microfluidic chip offers a portable, simple, accurate, and sensitive strategy for detecting harmful environmental and food substances.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Colorimetry , DNA , Electrochemical Techniques , Hydrogels , Limit of Detection , Hydrogels/chemistry , Electrochemical Techniques/methods , Aptamers, Nucleotide/chemistry , DNA/chemistry , Malathion/analysis , Equipment Design , Lab-On-A-Chip Devices , Organophosphorus Compounds/analysis , Organophosphorus Compounds/chemistry , Microfluidic Analytical Techniques/instrumentation
15.
Micromachines (Basel) ; 15(6)2024 May 24.
Article in English | MEDLINE | ID: mdl-38930658

ABSTRACT

Microelectromechanical system (MEMS) cantilever resonators suffer from high motional impedance (Rm). This paper investigates the use of mechanically coupled multi-cantilever piezoelectric MEMS resonators in the resolution of this issue. A double-sided actuating design, which utilizes a resonator with a 2.5 µm thick AlN film as the passive layer, is employed to reduce Rm. The results of experimental and finite element analysis (FEA) show agreement regarding single- to sextuple-cantilever resonators. Compared with a standalone cantilever resonator, the multi-cantilever resonator significantly reduces Rm; meanwhile, the high quality factor (Q) and effective electromechanical coupling coefficient (Kteff2) are maintained. The 30 µm wide quadruple-cantilever resonator achieves a resonance frequency (fs) of 55.8 kHz, a Q value of 10,300, and a series impedance (Rs) as low as 28.6 kΩ at a pressure of 0.02 Pa; meanwhile, the smaller size of this resonator compared to the existing multi-cantilever resonators is preserved. This represents a significant advancement in MEMS resonators for miniaturized ultra-low-power oscillator applications.

16.
Micromachines (Basel) ; 15(6)2024 May 29.
Article in English | MEDLINE | ID: mdl-38930686

ABSTRACT

By leveraging the benefits of a high energy density, miniaturization and integration, acoustic-wave-driven micromotors have recently emerged as powerful tools for microfluidic actuation. In this study, a Lamb-wave-driven micromotor is proposed for the first time. This motor consists of a ring-shaped Lamb wave actuator array with a rotor and a fluid coupling layer in between. On a driving mechanism level, high-frequency Lamb waves of 380 MHz generate strong acoustic streaming effects over an extremely short distance; on a mechanical design level, each Lamb wave actuator incorporates a reflector on one side of the actuator, while an acoustic opening is incorporated on the other side to limit wave energy leakage; and on electrical design level, the electrodes placed on the two sides of the film enhance the capacitance in the vertical direction, which facilitates impedance matching within a smaller area. As a result, the Lamb-wave-driven solution features a much lower driving voltage and a smaller size compared with conventional surface acoustic-wave-driven solutions. For an improved motor performance, actuator array configurations, rotor sizes, and liquid coupling layer thicknesses are examined via simulations and experiments. The results show the micromotor with a rotor with a diameter of 5 mm can achieve a maximum angular velocity of 250 rpm with an input voltage of 6 V. The proposed micromotor is a new prototype for acoustic-wave-driven actuators and demonstrates potential for lab-on-a-chip applications.

18.
Biosensors (Basel) ; 14(6)2024 May 29.
Article in English | MEDLINE | ID: mdl-38920584

ABSTRACT

The µTAS/LOC, a highly integrated microsystem, consolidates multiple bioanalytical functions within a single chip, enhancing efficiency and precision in bioanalysis and biomedical operations. Microfluidic centrifugation, a key component of LOC devices, enables rapid capture and enrichment of tiny objects in samples, improving sensitivity and accuracy of detection and diagnosis. However, microfluidic systems face challenges due to viscosity dominance and difficulty in vortex formation. Acoustic-based centrifugation, particularly those using surface acoustic waves (SAWs), have shown promise in applications such as particle concentration, separation, and droplet mixing. However, challenges include accurate droplet placement, energy loss from off-axis positioning, and limited energy transfer from low-frequency SAW resonators, restricting centrifugal speed and sample volume. In this work, we introduce a novel ring array composed of eight Lamb wave resonators (LWRs), forming an Ultra-Fast Centrifuge Tunnel (UFCT) in a microfluidic system. The UFCT eliminates secondary vortices, concentrating energy in the main vortex and maximizing acoustic-to-streaming energy conversion. It enables ultra-fast centrifugation with a larger liquid capacity (50 µL), reduced power usage (50 mW) that is one order of magnitude smaller than existing devices, and greater linear speed (62 mm/s), surpassing the limitations of prior methods. We demonstrate successful high-fold enrichment of 2 µm and 10 µm particles and explore the UFCT's potential in tissue engineering by encapsulating cells in a hydrogel-based micro-organ with a ring structure, which is of great significance for building more complex manipulation platforms for particles and cells in a bio-compatible and contactless manner.


Subject(s)
Centrifugation , Humans , Lab-On-A-Chip Devices , Microfluidic Analytical Techniques , Acoustics
19.
J Nutr ; 154(7): 2157-2166, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38740185

ABSTRACT

BACKGROUND: We previously reported that delayed allergenic food introduction in infancy did not increase food allergy risk until age 4 y within our prospective cohort. However, it remains unclear whether other aspects of maternal or infant diet play roles in the development of childhood food allergy. OBJECTIVES: We examined the relationship between maternal pregnancy and infant dietary patterns and the development of food allergies until age 8 y. METHODS: Among 1152 Singapore Growing Up in Singapore Towards healthy Outcomes study mother-infant dyads, the infant's diet was ascertained using food frequency questionnaires at 18 mo. Maternal dietary patterns during pregnancy were derived from 24-h diet recalls. Food allergy was determined through interviewer-administered questionnaires at regular time points from infancy to age 8 y and defined as a positive history of allergic reactions, alongside skin prick tests at 18 mo, 3, 5, and 8 y. RESULTS: Food allergy prevalence was 2.5% (22/883) at 12 mo and generally decreased over time by 8 y (1.9%; 14/736). Higher maternal dietary quality was associated with increased risk of food allergy (P ≤ 0.016); however, odds ratios were modest. Offspring food allergy risk ≤8 y showed no associations with measures of infant diet including timing of solids/food introduction (adjusted odds ratio [aOR]: 0.90; 95% confidence interval [CI]: 0.42, 1.92), infant's diet quality (aOR: 0.93; 95% CI: 0.88, 0.99) or diet diversity (aOR: 0.84; 95% CI: 0.6, 1.19). Most infants (89%) were first introduced to cow milk protein within the first month of life, while egg and peanut introduction were delayed (58.3% introduced by mean age 8.8 mo and 59.8% by mean age 18.1 mo, respectively). CONCLUSIONS: Apart from maternal diet quality showing a modest association, infant's allergenic food introduction, diet quality, and dietary diversity were not associated with food allergy development in this Asian pediatric population. Interventional studies are needed to evaluate the efficacy of these approaches to food allergy prevention across different populations.


Subject(s)
Diet , Food Hypersensitivity , Humans , Female , Food Hypersensitivity/epidemiology , Singapore/epidemiology , Infant , Pregnancy , Male , Child, Preschool , Prospective Studies , Adult , Child , Risk Factors , Cohort Studies , Maternal Nutritional Physiological Phenomena , Infant Food , Infant Nutritional Physiological Phenomena , Prevalence , Dietary Patterns
20.
Org Lett ; 26(22): 4690-4694, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38804574

ABSTRACT

Zn-mediated generation of alkoxyl radicals from N-alkoxyphthalimides emerged as an efficient approach for forming diverse and valuable alkyl radicals through ß-scission or a hydrogen atom transfer process. The alkyl radical species can be further trapped by α-trifluoromethyl alkenes to construct a series of gem-difluoroalkenes.

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