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2.
Int J Mol Sci ; 25(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38731930

ABSTRACT

Soluble starch synthases (SSs) play important roles in the synthesis of cassava starch. However, the expression characteristics of the cassava SSs genes have not been elucidated. In this study, the MeSSIII-1 gene and its promoter, from SC8 cassava cultivars, were respectively isolated by PCR amplification. MeSSIII-1 protein was localized to the chloroplasts. qRT-PCR analysis revealed that the MeSSIII-1 gene was expressed in almost all tissues tested, and the expression in mature leaves was 18.9 times more than that in tuber roots. MeSSIII-1 expression was induced by methyljasmonate (MeJA), abscisic acid (ABA), and ethylene (ET) hormones in cassava. MeSSIII-1 expression patterns were further confirmed in proMeSSIII-1 transgenic cassava. The promoter deletion analysis showed that the -264 bp to -1 bp MeSSIII-1 promoter has basal activity. The range from -1228 bp to -987 bp and -488 bp to -264 bp significantly enhance promoter activity. The regions from -987 bp to -747 bp and -747 bp to -488 bp have repressive activity. These findings will provide an important reference for research on the potential function and transcriptional regulation mechanisms of the MeSSIII-1 gene and for further in-depth exploration of the regulatory network of its internal functional elements.


Subject(s)
Gene Expression Regulation, Plant , Manihot , Plant Proteins , Plants, Genetically Modified , Promoter Regions, Genetic , Manihot/genetics , Manihot/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Genetically Modified/genetics , Starch Synthase/genetics , Starch Synthase/metabolism , Abscisic Acid/pharmacology , Abscisic Acid/metabolism , Ethylenes/metabolism
3.
Sci Rep ; 14(1): 12518, 2024 05 31.
Article in English | MEDLINE | ID: mdl-38822099

ABSTRACT

To investigate the application of MRI-based vertebral bone quality (VBQ) score in assessing bone mineral density (BMD) for patients with adolescent idiopathic scoliosis (AIS). We reviewed the data of AIS patients between January 2021 and October 2023 with MRI, whole-spine plain radiographs, quantitative computed tomography (QCT) and general information. VBQ score was calculated using T1-weighted MRI. Univariate analysis was applied to present the differences between variables of patients with normal BMD group (QCT Z-score > - 2.0) and low BMD group (QCT Z-score ≤ - 2.0). The correlation between VBQ score and QCT Z-score was analyzed with Pearson correlation test. A multivariate logistic regression model was used to determine the independent factors related to low BMD. Receiver operating characteristic curve (ROC) was drawn to analyze the diagnostic performance of VBQ score in distinguishing low BMD. A total of 136 AIS patients (mean age was 14.84 ± 2.10 years) were included, of which 41 had low BMD. The low BMD group had a significantly higher VBQ score than that in normal group (3.48 ± 0.85 vs. 2.62 ± 0.62, P < 0.001). The VBQ score was significantly negative correlated with QCT Z score (r = - 0.454, P < 0.001). On multivariate analysis, VBQ score was independently associated with low BMD (OR: 4.134, 95% CI 2.136-8.000, P < 0.001). The area under the ROC curve indicated that the diagnostic accuracy of the VBQ score for predicting low BMD was 81%. A sensitivity of 65.9% with a specificity of 88.4% could be achieved for distinguishing low BMD by setting the VBQ score cutoff as 3.18. The novel VBQ score was a promising tool in distinguishing low BMD in patients with AIS and could be useful as opportunistic assessment for screening and complementary evaluation to QCT before surgery.


Subject(s)
Bone Density , Magnetic Resonance Imaging , Scoliosis , Humans , Scoliosis/diagnostic imaging , Adolescent , Female , Male , Magnetic Resonance Imaging/methods , ROC Curve , Spine/diagnostic imaging , Spine/pathology , Child , Tomography, X-Ray Computed/methods , Retrospective Studies
4.
World J Gastrointest Oncol ; 16(2): 563-570, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38425401

ABSTRACT

BACKGROUND: Early adenocarcinoma mixed with a neuroendocrine carcinoma (NEC) component arising in the gastroesophageal junctional (GEJ) region is rare and even rarer in young patients. Here, we report such a case in a 29-year-old Chinese man. CASE SUMMARY: This patient presented to our hospital with a 3-mo history of dysphagia and regurgitation. Upper endoscopy revealed an elevated nodule in the distal esophagus 1.6 cm above the GEJ line, without Barrett's esophagus or involvement of the gastric cardia. The nodule was completely resected by endoscopic submucosal dissection (ESD). Pathological examination confirmed diagnosis of intramucosal adenocarcinoma mixed with an NEC component, measuring 1.5 cm. Immunohistochemically, both adenocarcinoma and NEC components were positive for P53 with a Ki67 index of 90%; NEC was positive for synaptophysin and chromogranin. Next-generation sequencing of 196 genes demonstrated a novel germline mutation of the ERCC3 gene in the DNA repair pathway and a germline mutation of the RNF43 gene, a common gastric cancer driver gene, in addition to pathogenic somatic mutations in P53 and CHEK2 genes. The patient was alive without evidence of the disease 36 mo after ESD. CONCLUSION: Early adenocarcinoma with an NEC component arising in the distal esophageal side of the GEJ region showed evidence of gastric origin.

5.
Analyst ; 149(6): 1766-1773, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38372348

ABSTRACT

Quantitative carbohydrate analysis faces challenges in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), including insufficient sensitivity and inconsistent spatial distribution of ion intensity. This study introduces an innovative sample preparation approach, the Rapidly Freeze-Drying Droplet (RFDD) method, aimed at overcoming these challenges by enhancing the homogeneity of the sample morphology and signal intensity in MALDI. Compared to conventional preparation methods, the RFDD method reduces the laser energy threshold and demonstrates a remarkable increase in signal intensity for carbohydrates, facilitating the detection of high-molecular-weight polysaccharides (>10 kDa). The RFDD-prepared samples exhibit a uniformly distributed signal intensity that overcomes the 'sweet spot' issue in MALDI. The enhanced signal intensity and reproducibility lead to reliable quantitative analysis of carbohydrates, eliminating the need for expensive isotopic standards in each sample. A straightforward and accessible approach is presented for general laboratories, revolutionizing carbohydrate analysis in MALDI-MS.


Subject(s)
Carbohydrates , Polysaccharides , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Reproducibility of Results
6.
Clin Pharmacol Drug Dev ; 13(3): 307-314, 2024 03.
Article in English | MEDLINE | ID: mdl-38189592

ABSTRACT

The incidence of type 2 diabetes is high, and the existing metformin hydrochloride (MH) tablets of 250 mg cannot meet the demands of the Chinese drug market. This study aimed to evaluate the bioequivalence and safety of generic formulations of MH tablets (test formulation [T], 250 mg/tablet) and innovative products (reference formulation [R], 250 mg/tablet) under fasting conditions. This was an open-label, single-dose, 2-period, 2-sequence crossover, single-center, randomized phase I clinical trial. T and R were considered bioequivalent if the adjusted geometric mean ratios (GMRs) and 90% confidence intervals of the area under the curve (AUC) and maximum concentration (Cmax ) were within the range of 0.8-1.25. Thirty-five participants completed the trial. The T/R adjusted GMRs (95.7% for Cmax , 98.7% for AUC0→t , 98.8% for AUC0→∞ ) were within the acceptable bioequivalence range of 80%-125%. No serious adverse events or suspected or unexpected serious adverse reactions occurred during this trial. The study findings confirmed that generic MH is a well-tolerated and bioequivalent alternative to innovative products under fasting conditions in healthy Chinese participants. (www.chinadrugtrials.org.cn; registration no. CTR20190356).


Subject(s)
Diabetes Mellitus, Type 2 , Metformin , Humans , Therapeutic Equivalency , Metformin/adverse effects , Diabetes Mellitus, Type 2/drug therapy , Fasting , Tablets , China
7.
Res Vet Sci ; 168: 105136, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38183894

ABSTRACT

Avian malaria is a vector-borne parasitic disease caused by Plasmodium infection transmitted to birds by mosquitoes. The aim of this systematic review was to analyze the global prevalence of malaria and risk factors associated with infection in wild birds. A systematic search of the databases CNKI, WanFang, VIP, PubMed, and ScienceDirect was performed from database inception to 24 February 2023. The search identified 3181 retrieved articles, of which 52 articles met predetermined inclusion criteria. Meta-analysis was performed using the random-effects model. The estimated pooled global prevalence of Plasmodium infection in wild birds was 16%. Sub-group analysis showed that the highest prevalence was associated with adult birds, migrant birds, North America, tropical rainforest climate, birds captured by mist nets, detection of infection by microscopy, medium quality studies, and studies published after 2016. Our study highlights the need for more understanding of Plasmodium prevalence in wild birds and identifying risk factors associated with infection to inform future infection control measures.


Subject(s)
Malaria, Avian , Plasmodium , Animals , Prevalence , Mosquito Vectors/parasitology , Animals, Wild , Malaria, Avian/epidemiology , Malaria, Avian/parasitology , Birds/parasitology
8.
Nat Chem Biol ; 20(4): 484-492, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37945893

ABSTRACT

GPR101 is an orphan G protein-coupled receptor actively participating in energy homeostasis. Here we report the cryo-electron microscopy structure of GPR101 constitutively coupled to Gs heterotrimer, which reveals unique features of GPR101, including the interaction of extracellular loop 2 within the 7TM bundle, a hydrophobic chain packing-mediated activation mechanism and the structural basis of disease-related mutants. Importantly, a side pocket is identified in GPR101 that facilitates in silico screening to identify four small-molecule agonists, including AA-14. The structure of AA-14-GPR101-Gs provides direct evidence of the AA-14 binding at the side pocket. Functionally, AA-14 partially restores the functions of GH/IGF-1 axis and exhibits several rejuvenating effects in wild-type mice, which are abrogated in Gpr101-deficient mice. In summary, we provide a structural basis for the constitutive activity of GPR101. The structure-facilitated identification of GPR101 agonists and functional analysis suggest that targeting this orphan receptor has rejuvenating potential.


Subject(s)
Receptors, G-Protein-Coupled , Mice , Animals , Cryoelectron Microscopy , Receptors, G-Protein-Coupled/metabolism , Ligands
9.
Nanoscale ; 16(1): 373-383, 2023 Dec 21.
Article in English | MEDLINE | ID: mdl-38063775

ABSTRACT

With the expansion of global energy problems and the deepening of research on oxygen reduction reaction (ORR) in alkaline media, the development of low cost and high electrocatalytic performance catalysts has become a research hotspot. In this study, a hexagonal Pd-C-MnOOH composite catalyst was prepared by using the triblock copolymer P123 as the reducing agent and protective agent, sucrose as the carbon source and self-made MnOOH as the carrier under hydrothermal conditions. When the Pd load is 20% and the C/MnOOH ratio is 1 : 1, the 20% Pd-C-MnOOH-1 : 1 catalyst obtained by the one-step method has the highest ORR activity and stability in the alkaline system. At 1600 rpm, the limiting diffusion current density and half-wave potential of the 20% Pd-C-MnOOH-1 : 1 electrocatalyst are -4.78 mA cm-2 and 0.84 V, respectively, which are better than those of the commercial 20%Pd/C catalyst. According to the Koutecky-Levich (K-L) equation and the linear fitting results, the electron transfer number of the 20%Pd-C-MnOOH-1 : 1 electrocatalyst for the oxygen reduction reaction is 3.8, which is similar to that of a 4-electron process. After 1000 cycles, the limiting diffusion current density of the 20%Pd-C-MnOOH-1 : 1 catalyst is -4.61 mA cm-2, which only decreases by 3.7%, indicating that the 20%Pd-C-MnOOH-1 : 1 catalyst has good stability. The reason for the improvement of the ORR performance of the Pd-C-MnOOH composite catalyst is the improvement of the conductivity of the carbon layer formed by original carbonization, the regular hexagonal highly active Pd particles and the synergistic catalytic effect between Pd and MnOOH. The method of introducing triblock copolymers in the synthesis of oxides and metal-oxide composite catalysts is expected to be extended to other electrocatalysis fields.

10.
J Med Invest ; 70(3.4): 524-529, 2023.
Article in English | MEDLINE | ID: mdl-37940544

ABSTRACT

OBJECTIVES: The aim of the present study was to introduce a novel three-dimensional computed tomography (3DCT)-based three-column classification (named "MLP classification system") of intertrochanteric fractures and evaluate its reproducibility and reliability. METHODS: From September 2020 to September 2022, a total of 258 consecutive patients (60 male, 198 female;mean age 81.3 years) with intertrochanteric fractures were included in this study. The fracture in each case was assessed using a novel three-dimensional computed tomography-based three-column classification. Two examiners tested the intra and inter-observer reliability of this new classification system using kappa variance. RESULTS: The intertrochanteric region was divided into the medial column, lateral column, and posterior column. Intertrochanteric fractures were documented as M0/1/2L0/1/2/3P0/1/2/3. All fractures were classifiable into the new classification system. The intra-observer kappa values were 0.91 and 0.89, while the inter-observer kappa value was 0.82, both indicating almost perfect reliability. CONCLUSION: This novel 3DCT-based MLP classification system for intertrochanteric fractures is comprehensive, and reproducible with good agreement. It is based on proximal femur biomechanic characteristics and traumatic mechanism, contributing to formulating more reasonable treatment protocols involving various late-model internal fixation devices. J. Med. Invest. 70 : 524-529, August, 2023.


Subject(s)
Hip Fractures , Imaging, Three-Dimensional , Humans , Male , Female , Aged, 80 and over , Reproducibility of Results , Observer Variation , Tomography, X-Ray Computed/methods , Hip Fractures/diagnostic imaging , Hip Fractures/surgery
11.
Anticancer Res ; 43(12): 5589-5596, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38030166

ABSTRACT

BACKGROUND/AIM: Systemic treatment for metastatic colorectal cancer (CRC) includes chemotherapy in combination with a targeted antibody. Novel targeted therapies and immunotherapies are introduced for specific molecular subgroups. Prognostic relevant determinants are still under investigation. PATIENTS AND METHODS: Systemic therapies of an unselected patient cohort with metastatic CRC were retrospectively analyzed. Treatment outcome was evaluated according to time-to-next-treatment (TTNT) and frequency of conversion surgery and compared between subgroups stratified by primary tumor side, molecular profile, sex and age, and metastases sites. RESULTS: More than 50% of patients with locally advanced or metastatic CRC underwent secondary resection after first-line systemic therapy. Rectum carcinoma had the best prognosis under anti-EGFR-antibody treatment. Female patients had a worse prognosis than male patients in late disease stage. Young patients demonstrated poor response to systemic therapy, but a high rate of conversion surgeries. Conversely, elderly patients benefited from systemic therapy but underwent surgery less frequently. Liver and lung metastases had a worse prognosis than other metastases sites, whereas lung metastases were more likely to be resected than liver metastases in early disease stage. CONCLUSION: Patient age, sex, primary tumor localization, and metastatic sites are prognostic factors that could guide future treatment decisions for the therapy of metastatic CRC.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Liver Neoplasms , Lung Neoplasms , Rectal Neoplasms , Humans , Male , Female , Aged , Retrospective Studies , Colorectal Neoplasms/pathology , Colonic Neoplasms/pathology , Rectal Neoplasms/therapy , Rectal Neoplasms/pathology , Prognosis , Lung Neoplasms/drug therapy , Liver Neoplasms/secondary
12.
Phytochemistry ; 215: 113861, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37726084

ABSTRACT

Seven previously undescribed cytochalasans, namely, boerechalasins A-G, together with one analogue, were characterized from the solid culture of the fungus Boeremia exigua. Their structures and absolute configurations were elucidated on the basis of extensive spectroscopic analysis as well as electronic circular dichroism calculations. Remarkably, boerechalasin F possessed an unusual sulfoxide moiety that might be derived from methionine, while boerechalasin G had an unusual 5-methylcyclohexane-1,2,3-triol substituent at N-2 position. Boerechalasins A and E exhibited inhibitory activities against nitric oxide production in LPS-induced RAW264.7 macrophages with IC50 values of 21.9 and 5.7 µM, respectively. Boerechalasin F displayed cytotoxicity against human MCF‒7 cells with an IC50 value of 22.8 µM.


Subject(s)
Ascomycota , Humans , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Macrophages , Cytochalasins/pharmacology , Cytochalasins/chemistry , Molecular Structure
13.
Int J Ophthalmol ; 16(9): 1386-1394, 2023.
Article in English | MEDLINE | ID: mdl-37724272

ABSTRACT

Pterygium is a prevalent ocular disease that can cause discomfort and vision impairment. Early and accurate diagnosis is essential for effective management. Recently, artificial intelligence (AI) has shown promising potential in assisting clinicians with pterygium diagnosis. This paper provides an overview of AI-assisted pterygium diagnosis, including the AI techniques used such as machine learning, deep learning, and computer vision. Furthermore, recent studies that have evaluated the diagnostic performance of AI-based systems for pterygium detection, classification and segmentation were summarized. The advantages and limitations of AI-assisted pterygium diagnosis and discuss potential future developments in this field were also analyzed. The review aims to provide insights into the current state-of-the-art of AI and its potential applications in pterygium diagnosis, which may facilitate the development of more efficient and accurate diagnostic tools for this common ocular disease.

14.
Appl Opt ; 62(14): 3519-3527, 2023 May 10.
Article in English | MEDLINE | ID: mdl-37706964

ABSTRACT

A switchable and tunable dual-function absorber/polarization converter is presented in this work. The constitution of the structure, which incorporates patterned graphene and photosensitive silicon (Si), can minimize undesired optical losses. Simulated results show that when the Si is metallic, the structure behaves as a broadband absorption of more than 90% in the range of 1.45-3.36 THz. Its peak absorption can be tuned from 22% to 99.8% by changing the Fermi energy of graphene. Furthermore, the interference theory analyzes the physical mechanism for broadband absorption. When the Si is in the dielectric state, the structure has a transmission polarization conversion function, which realizes the conversion from linear to cross-polarized waves. The polarization conversion ratio (PCR) is greater than 90% in the 3.82-4.43 THz range. Meanwhile, the cross-polarization transmission can be dynamically tuned from 28% to 97%, and the PCR can also be tuned from 17% to 99.9% by adjusting the conductivity of the Si. The reason for realizing polarization conversion is explained by the polarization decomposition method. This study provides a design opinion of high-performance multifunctional tunable terahertz devices.

15.
Ann Clin Lab Sci ; 53(4): 619-629, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37625837

ABSTRACT

OBJECTIVE: To investigate the role of the lncRNA MEG3 (MEG3) in opposing the biochemical processes thought to be involved in the development of atherosclerosis (AS). METHODS: Thirty patients with AS and thirty healthy control subjects were enrolled in this study. The expression of MEG3, miR-200b-3p and ABCA1 was analyzed by RT-qPCR in the individuals and the macrophages-derived foam cells. Lipid accumulation was detected by oil red O staining. Cholesterol efflux was measured by ELISA assay in the foam cells. Expression of miR-200b-3p was identified by sequencing. Targeting relationships were determined by dual luciferase assay between MEG3 and miR-200b-3p, miR-200b-3p and ABCA1. RESULTS: In the patients with AS, MEG3 and ABCA1 expression were decreased and miR-200b-3p expression was upregulated. Foam cells transfected with an expression vector (pcDNA3.1) containing MEG3 (pcDNA3.1-MEG3) induced decrease of lipid accumulation and increase of cholesterol efflux compared to cells transfected with control plasmid alone. Foam cells transfected by pcDNA3.1-MEG3 also showed decreased miR-200b-3p and increased ABCA1 expression. Interestingly, co-expression of miR-200b-3p partially prevented these effects of MEG3 expression. CONCLUSION: Expression of MEG3 is downregulated in the patients with AS and foam cells. Overexpressed MEG3 may act as an anti-atherosclerotic factor by reducing lipid accumulation and accelerating cholesterol efflux through the miR-200b-3p/ABCA1 axis.


Subject(s)
Atherosclerosis , MicroRNAs , Humans , Atherosclerosis/genetics , Biological Assay , Cholesterol , Lipids , MicroRNAs/genetics
16.
BMC Oral Health ; 23(1): 508, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37479973

ABSTRACT

BACKGROUND: Whether slim the face or not after removed third molars is the concern of some orthodontic treatment candidates. The aim of this article is to explore the volume changes of facial soft and hard tissues after third molars extraction, as well as develop a reproducible clinical protocol to precisely assess facial soft tissue volume change. METHODS: A non-randomized, non-blind, self-controlled pilot study was conducted. 24 adults aged 18-30 had ipsilateral third molars extracted. The body weight change was controlled within 2 kg. Structured light scans were taken under a standardized procedure pre-extraction (T0), three (T1), and six (T2) months post-extraction; CBCTs were taken at T0 and T2. The projection method was proposed to measure the soft tissue volume (STV) and the soft tissue volume change (STVC) by the Geomagic software. The hard tissue volume change (HTVC) was measured in the Dragonfly software. RESULTS: The final sample size is 23, including 5 males (age 26.6 ± 2.5 years) and 18 females (age 27.3 ± 2.5 years). The HTVC was - 2.33 ± 0.46ml on the extraction side. On the extraction side, the STV decreased by 1.396 (95% CI: 0.323-2.470) ml (P < 0.05) at T1, and increased by 1.753 (95% CI: -0.01-3.507) ml (P = 0.05) at T2. T2 and T0 had no difference (P > 0.05). The inter and intra-raters ICC of the projection method was 0.959 and 0.974. There was no correlation between the STVC and HTVC (P > 0.05). CONCLUSIONS: After ipsilateral wisdom teeth extraction, the volume of hard tissue on the extraction side reduces, and the volume of facial soft tissue does not change evidently. However, further research with large sample size is still needed. The STV measurement has excellent repeatability. It can be extended to other interested areas, including forehead, nose, paranasal, upper lip, lower lip and chin, which is meaningful in the field of orthodontics and orthopedics. TRIAL REGISTRATION: ChiCTR, ChiCTR1800018305 (11/09/2018), http://www.chictr.org.cn/showproj.aspx?proj=28868 .


Subject(s)
Dental Care , Female , Humans , Male , Chin , Lip , Pilot Projects , Adult
17.
Huan Jing Ke Xue ; 44(5): 2724-2734, 2023 May 08.
Article in Chinese | MEDLINE | ID: mdl-37177945

ABSTRACT

In order to discuss the response of soil nutrient content, stoichiometric ratio, and dynamic nutrient balance to the addition of multiple restrictive nutrients, the correlation between available nutrients and total nutrients in soil, as well as the indication of soil total and available stoichiometric characteristics, were studied in a desert grassland subjected to 4 years of nutrient addition treatments. The Ningxia desert grassland was used as the research object to carry out nitrogen (N) and phosphorus (P) addition experiments. The experiment included four treatments:control (CK), N addition[10 g·(m2·a)-1], P addition[10 g·(m2·a)-1], and NP co-addition (10 g·(m2·a)-1 N+10 g·(m2·a)-1 P). The results showed that:① in the fourth year of nutrient addition, soil total nitrogen (TN) content was significantly increased. The N:P ratio was significantly increased by N addition, and soil organic carbon (SOC) content was significantly increased by P addition and NP co-addition. In the third and fourth years of nutrient addition, the soil available N:P ratio (AN:AP) was significantly increased by N addition; N addition and NP co-addition significantly increased the content of ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N) but significantly reduced the soil available C:N ratio. P addition and NP co-addition significantly increased total phosphorus (TP) and soil available phosphorus (AP), whereas it significantly reduced the soil total and available C:P and N:P ratios. ② The interaction between N addition and P addition had a combined effect on NH4+-N, AP, available C:N, and AN:AP ratio of desert grassland. ③ The soil C:N ratio was relatively stable in desert grassland, soil N:P ratio was mainly limited by soil TP content, and the soil available C:P and AN:AP ratios were mainly limited by soil AP content. ④ There were cumulative effects of N and P additions on soil N, SOC, and inorganic nitrogen. N limitation in desert grassland was alleviated by N addition, whereas it was aggravated by P addition and NP co-addition. The variation coefficients of soil available stoichiometric characteristics were higher than that of soil total stoichiometric characteristics. Soil available stoichiometry was more sensitive to N and P addition than soil total stoichiometry in desert grassland, which could better reflect the effects of N and P addition on soil ecological stoichiometry and as a rapid indicator of soil nutrient status in desert grassland.

18.
Sensors (Basel) ; 23(9)2023 May 04.
Article in English | MEDLINE | ID: mdl-37177677

ABSTRACT

In this study, the integrated three-in-one (temperature, humidity, and wind speed) microsensor was made through the technology of the Micro-electro-mechanical Systems (MEMS) to measure three important physical quantities of the internal environment of the cold air pipe of the Heating, Ventilation and Air Conditioning (HVAC) in the factory, plan the installation positions of the integrated three-in-one microsensor and commercially available wind speed sensor required by the internal environment of the cold air pipe, and conduct the actual 310-h long term test and comparison. In the experiment, it was also observed that the self-made micro wind speed sensor had higher stability compared to the commercially available wind speed sensor (FS7.0.1L.195). The self-made micro wind speed sensor has a variation range of ±200 mm/s, while the commercially available wind speed sensor a variation range of ±1000 mm/s. The commercially available wind speed sensor (FS7.0.1L.195) can only measure the wind speed; however, the self-made integrated three-in-one microsensor can conduct real-time measurements of temperature and humidity according to the environment at that time, and use different calibration curves to know the wind speed. As a result, it is more accurate and less costly than commercially available wind speed sensors. The material cost of self-made integrated three-in-one microsensor includes chemicals, equipment usage fees, and wires. In the future, factories may install a large number of self-made integrated three-in-one microsensors in place of commercially available wind speed sensors. Through real-time wireless measurements, the self-made integrated three-in-one microsensors can achieve the control optimization of the HVAC cold air pipe's internal environment to improve the quality of manufactured materials.

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