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1.
Chin Med Sci J ; 39(1): 54-68, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38426411

RESUMO

Objective Dexmedetomidine (Dex) is a highly selective α2 adrenoceptor agonist that reduces blood pressure and heart rate. However, its ability to provide stable hemodynamics and a clinically significant reduction in blood loss in spine surgery is still a matter of debate. This study aimed to investigate the effects of Dex on intraoperative hemodynamics and blood loss in patients undergoing spine surgery.Methods The Web of Science, MEDLINE, EMBASE, and the Cochrane Library were searched up to February 2023 for randomized controlled trials (RCTs) including patients undergoing spine surgeries under general anaesthesia and comparing Dex and saline. A fixed- or random-effect model was used depending on heterogeneity.Results Twenty-one RCTs, including 1388 patients, were identified. Dex added the overall risk of intraoperative hypotension (odds ratio [OR]: 2.11; 95% confidence interval [CI]: 1.24 - 3.58; P=0.006) and bradycardia (OR: 2.48; 95%CI: 1.57 - 3.93; P=0.0001). The use of a loading dose of Dex led to significantly increased risks of intraoperative hypotension (OR: 2.00; 95%CI: 1.06 - 3.79; P=0.03) and bradycardia (OR: 2.28; 95%CI: 1.42 - 3.66; P=0.0007). For patients receiving total intravenous anesthesia, there was an increased risk of hypotension (OR: 2.90; 95%CI: 1.24 - 6.82; P=0.01) and bradycardia (OR: 2.66; 95%CI: 1.53 - 4.61; P=0. 0005). For patients in the inhalation anesthesia group, only an increased risk of bradycardia (OR: 4.95; 95%CI: 1.41 - 17.37; P=0.01) was observed. No significant increase in the risk of hypotension and bradycardia was found in the combined intravenous-inhalation anesthesia group. The incidence of severe hypotension (OR: 2.57; 95%CI: 1.05 - 6.32; P=0.04), but not mild hypotension, was increased. Both mild (OR: 2.55; 95%CI: 1.06 - 6.15; P=0.04) and severe (OR: 2.45; 95%CI: 1.43 - 4.20; P=0.001) bradycardia were associated with a higher risk. The overall analyses did not reveal significant reduction in intraoperative blood loss. However, a significant decrease in blood loss was observed in total inhalation anesthesia subgroup (mean difference [MD]: -82.97; 95%CI: -109.04 - -56.90; P<0.001).Conclusions Dex increases the risks of intraoperative hypotension and bradycardia in major spine surgery. The administration of a loading dose of Dex and the utilization of various anesthesia maintenance methods may potentially impact hemodynamic stability and intraoperative blood loss.


Assuntos
Dexmedetomidina , Hipotensão , Humanos , Dexmedetomidina/efeitos adversos , Bradicardia/induzido quimicamente , Bradicardia/tratamento farmacológico , Perda Sanguínea Cirúrgica , Hemodinâmica , Anestesia Geral , Hipotensão/induzido quimicamente , Hipotensão/epidemiologia , Hipotensão/tratamento farmacológico
2.
Food Chem ; 445: 138752, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38368701

RESUMO

In current study, polysaccharides from Hericium coralloides were extracted by heat reflux, acid-assisted, alkali-assisted, enzyme-assisted, ultrasonic-assisted, cold water, pressurized hot water, hydrogen peroxide/ascorbic acid system and acid-chlorite delignification methods, which were named as HRE-P, ACE-P, AAE-P, EAE-P, UAE-P, CWE-P, PHE-P, HAE-P, and ACD-P, respectively. Their physicochemical properties, structural characteristics, and antioxidant activities were investigated and compared. Experimental outcomes indicated notable variations in the extraction yields, chemical compositions, monosaccharide constituents and molecular weights of the obtained nine polysaccharides. HRE-P demonstrated the highest activity against ABTS and OH radicals, CWE-P against ABTS, DPPH, and superoxide radicals, and UAE-P against DPPH radicals. In addition, UAE-P, CWE-P, and HAE-P exhibited better protective effects on L929 cells, when compared to the other obtained polysaccharides. Additionally, correlation analysis indicated that monosaccharide composition and total polyphenol content were two prominent variables influencing the bioactivity of H. coralloides polysaccharides.


Assuntos
Antioxidantes , Benzotiazóis , Hericium , Polissacarídeos , Ácidos Sulfônicos , Antioxidantes/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Monossacarídeos/análise , Água/química
3.
Angew Chem Int Ed Engl ; 63(2): e202314304, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38009446

RESUMO

Bridged benzazepine scaffolds, possessing unique structural and physicochemical activities, are widespread in various natural products and drugs. The construction of these skeletons often requires elaborate synthetic effort with low efficiency. Herein, we develop a simple and divergent approach for constructing various bridged benzazepines by a photocatalytic intermolecular dearomatization of naphthalene derivatives with readily available α-amino acids. The bridged motif is created via a cascade sequence involving photocatalytic 1,4-hydroaminoalkylation, alkene isomerization and cyclization. Interestingly, the diastereoselectivity can be regulated through different reaction modes in the cyclization step. Moreover, aminohydroxylation and its further bromination have also been demonstrated to access highly functionalized bridged benzazepines. Preliminary mechanistic studies have been performed to get insights into the mechanism. This method provides a divergent synthetic approach for construction of highly functionalized bridged benzazepines, which have been otherwise difficult to access.

4.
Angew Chem Int Ed Engl ; 63(6): e202317299, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38105386

RESUMO

The construction of multiple continuous fully substituted carbon centers, which serve as unique structural motif in natural products, is a challenging topic in organic synthesis. Herein, we report a hydrated [3+2] cyclotelomerization of butafulvenes to create contiguous fully substituted carbon backbone. In the presence of scandium triflate, all-carbon skeleton with spiro fused tricyclic ring can be constructed in high diastereoselectivity by utilizing butafulvene as the synthon. Mechanistic studies suggest that this atom-economic reaction probably proceeds through a synergistic process containing butafulvenes dimerization and nucleophilic attack by water. In addition, the tricyclic product can undergo a series of synthetic derivatizations, which highlights the potential applications of this strategy. The recyclability of Sc(OTf)3 has also been demonstrated to show its robust performance in this hydrated cyclotelomerization.

5.
FASEB J ; 38(1): e23354, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085162

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and the development of novel therapeutic strategies for HNSCC requires a profound understanding of tumor cells and the tumor microenvironment (TME). Additionally, HNSCC has a poor prognosis, necessitating the use of genetic markers for predicting clinical outcomes in HNSCC. In this study, we performed single-cell sequencing analysis on tumor tissues from seven HNSCC patients, along with one adjacent normal tissue. Firstly, the analysis of epithelial cell clusters revealed two clusters of malignant epithelial cells, characterized by unique gene expression patterns and dysregulated signaling pathways compared to normal epithelial cells. Secondly, the examination of the TME unveiled extensive crosstalk between fibroblasts and malignant epithelial cells, potentially mediated through ligand-receptor interactions such as COL1A1-SDC1, COL1A1-CD44, and COL1A2-SDC1. Furthermore, transcriptional heterogeneity was observed in immune cells present in the TME, including macrophages and dendritic cells. Finally, leveraging the gene expression profiles of malignant epithelial cells, we developed a prognostic model comprising six genes, which we validated using two independent datasets. These findings shed light on the heterogeneity within HNSCC tumors and the intricate interplay between malignant cells and the TME. Importantly, the developed prognostic model demonstrates high efficacy in predicting the survival outcomes of HNSCC patients.


Assuntos
Carcinoma , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Prognóstico , Neoplasias de Cabeça e Pescoço/genética , Células Epiteliais , Microambiente Tumoral/genética
6.
Nat Commun ; 14(1): 7087, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925506

RESUMO

As a large number of organic compounds possessing two isoprene units, monoterpenes and monoterpenoids play important roles in pharmaceutical, cosmetic, agricultural, and food industries. In nature, monoterpenes are constructed from geranyl pyrophosphate (C10) via various transformations. Herein, the bulk C5 chemical-isoprene, is used for the creation of various monoterpenoids via a nucleophilic aromatization of monoterpenes under cascade catalysis of nickel and iodine. Drugs and oil mixtures from conifer and lemon can be convergently transformed to the desired monoterpenoid. Preliminary mechanistic studies are conducted to get insights about reaction pathway. Two types of cyclic monoterpenes can be respectively introduced onto two similar heterocycles via orthogonal C-H functionalization. And various hybrid terpenyl indoles are programmatically assembled from abundant C5 or C10 blocks. This work not only contributes a high chemo-, regio-, and redox-selective transformation of isoprene, but also provides a complementary approach for the creation of unnatural monoterpenoids.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37091860

RESUMO

Objective: Essential hypertension (EH) is a common cardiovascular disease that endangers human health. Its pathogenesis is complex and has not been fully elucidated. We explore the association between EH and interactions among polymorphisms of the angiotensin converting enzyme (ACE) gene in the Hefei region, Anhui, China. Methods: A total of 500 participants (400 hypertensive and 100 normotensive) were included in this study. The polymorphisms were detected via improved multiple ligase detection reaction (iMLDR). To improve the accuracy of prediction, multifactor dimensionality reduction (MDR) was used to analyze the overall effect of interactions among seven loci on the incidence of EH. Results: The frequencies of polymorphisms in the ACE genes rs12709426, rs4291, rs4309, rs4331, rs4343, rs4459609, and rs4461142 in the EH group were not statistically significantly different from those in the control group. We also found that the single nucleotide polymorphism (SNP) rs12709426 only had a homozygous AA genotype and no polymorphisms. There were no differences in the frequency of genetic polymorphisms between the EH and control groups. The best model explaining the EH group was the combined effect of ACE genes rs4291, rs4309, and rs4461142. Conclusion: There is an interaction effect among ACE gene loci in EH patients in Hefei region, Anhui, China. Also, the ACE gene SNP rs12709426 only has a homozygous AA genotype and does not show an association with EH.


Assuntos
Hipertensão , Peptidil Dipeptidase A , Humanos , Frequência do Gene/genética , Peptidil Dipeptidase A/genética , Predisposição Genética para Doença , Hipertensão Essencial/genética , Hipertensão/genética , Polimorfismo de Nucleotídeo Único/genética , China/epidemiologia , Genótipo
8.
Zhongguo Zhen Jiu ; 43(2): 123-7, 2023 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-36808503

RESUMO

OBJECTIVE: To observe the clinical efficacy of acupuncture for prevention of moderate to severe seasonal allergic rhinitis. METHODS: A total of 105 patients with moderate to severe seasonal allergic rhinitis were randomly divided into an observation group (53 cases, 3 cases dropped off) and a control group (52 cases, 4 cases dropped off). The patients in the observation group were treated with acupuncture at Yintang (GV 24+), Yingxiang (LI 20), Hegu (LI 4), Zusanli (ST 36), Fengchi (GB 20), Feishu (BL 13), etc. 4 weeks before the seizure period, once every other day, 3 times a week for 4 weeks. The patients in the control group were not given any intervention before the seizure period. Emergency drugs can be given appropriately during the seizure period in both groups. After seizure period, the seizure rate was recorded in the two groups; before treatment and on week 1, 2, 4, 6 of seizure period after treatment, the rhinoconjunctivitis quality of life questionnaire (RQLQ) score and total nasal symptom score (TNSS) were observed in the two groups; the rescue medication score (RMS) was recorded on week 1-6 of seizure period in the two groups. RESULTS: The seizure rate of the observation group was 84.0% (42/50), which was lower than 100.0% (48/48) in the control group (P<0.05). After treatment, the scores of RQLQ and TNSS at each time point of seizure period were decreased compared with before treatment in the observation group (P<0.01), which were lower than the control group (P<0.01). The RMS score at each time point of seizure period in the observation group was lower than the control group (P<0.05, P<0.01). CONCLUSION: Acupuncture can reduce the incidence of moderate to severe seasonal allergic rhinitis, relieve the symptoms, improve the quality of life and reduce the use of emergency drugs.


Assuntos
Terapia por Acupuntura , Rinite Alérgica Sazonal , Rinite Alérgica , Humanos , Rinite Alérgica/terapia , Qualidade de Vida , Pontos de Acupuntura , Resultado do Tratamento , Convulsões
9.
J Electrocardiol ; 76: 79-84, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36512934

RESUMO

BACKGROUNDS: Study concerning the clinical features, electrocardiogram (ECG) findings and outcomes in patients presenting with acute total occlusion of left main coronary artery (LM) without collateral circulation is limited. METHODS: 25 patients with acute total LM occlusion without collateral circulation by emergency coronary angiography, from muti-center registry, were retrospectively studied. The clinical and angiographic characteristics, ECG and in-hospital mortality were reviewed. RESULTS: Nineteen patients (76%) presented with cardiogenic shock. Twelve (60%, 12/20) patients had coronary slow flow or no reflow phenomenon after primary percutaneous coronary intervention (PCI). The in-hospital mortality rate was 88% (n = 22). All the patients presented with ST-segment elevation myocardial ischemia (STEMI) pattern, mostly involving leads I, aVL, V2, V3, V4, V5 and ST-segment depression in leads II, III and aVF. CONCLUSIONS: Acute total LM occlusion without collateral circulation portends high in-hospital mortality. Anterior ST elevation in the precordial leads from V2 to V4 through V6, and ST elevation in leads I and aVL, accompanying with ST depression in the inferior leads is associated with acute total LM occlusion without collateral circulation.


Assuntos
Oclusão Coronária , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Estudos Retrospectivos , Vasos Coronários , Circulação Colateral , Eletrocardiografia , Oclusão Coronária/diagnóstico , Oclusão Coronária/cirurgia , Oclusão Coronária/complicações , Angiografia Coronária , Arritmias Cardíacas
10.
Phys Chem Chem Phys ; 25(1): 847-856, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36511817

RESUMO

In this work, we systematically investigate the photocatalytic mechanism of g-C3N4/BiOI (001) through hybrid functional calculations based on first-principles theory. The staggered band structure is observed in the g-C3N4/BiOI (001); meanwhile, a built-in electric field exists from the g-C3N4 monolayer to the BiOI surface at the interface. BiOI has lower band edges, which bend downward at the interface; whereas g-C3N4 has higher band edges, which bend upward. With Coulomb interaction and the built-in electric field, photo-generated electrons in the conduction bands (CB) of BiOI recombine with photo-generated holes in the valence bands (VB) of g-C3N4. Meanwhile, the stronger reduction capacity for photo-excited electrons in the g-C3N4's CB and the stronger oxidation capacity for photo-generated holes in the BiOI (001)'s VB are retained. Therefore, a direct Z-scheme heterostructure character is presented. As a result, the electrons and holes generated by the photons can be separated and migrate highly effectively at the interface. The separated electrons and holes can effectively participate in the redox reactions with water/pollutants to produce the photocatalytically reactive species superoxide ions (˙O2-) and hydroxyl radicals (˙OH), respectively. This is consistent with the experimental results. It is also worth noting that the g-C3N4/BiOI (001) heterostructure shows a larger difference in the effective mass of carriers. Therefore, the direct Z-scheme charge transfer and separation mechanism and the larger effective mass difference of carriers lead to the superior photocatalytic activity of the g-C3N4/BiOI (001) in experiments. A few speculations and controversies that arose from the experiments are clarified.

11.
Artigo em Inglês | MEDLINE | ID: mdl-36387359

RESUMO

Objective: The aim of the study is to explore the effects and mechanisms of action of Ziyin Qianyang Formula (ZYQYF) on renal fibrosis in spontaneously hypertensive rats (SHRs). Methods: Forty SHRs were randomly divided into a model group, Ziyin Qianyang Formula regular-dose and high-dose groups (ZYQYF-R, 20 g/kg; ZYQYF-H, 40 g/kg), and a western medicine group (enalapril 10 mg/kg), and 10 Sprague-Dawley rats were selected as the normal group. The rats received continuous gavage administration for 6 weeks and systolic blood pressure (SBP) measurements were obtained every fortnight. The serum levels of urea, serum creatinine (sCr), and uric acid (UA) were measured; the pathological morphology and collagen content of the kidneys were observed by hematoxylin-eosin (HE) and Masson staining; and the serum Ang II level was measured by an enzyme-linked immunosorbent assay (ELISA). Transforming growth factor (TGF)-ß1, Smad-2, Smad-3, and Smad-7 protein and mRNA expressions in kidney tissues was evaluated by western blotting and reverse transcription-polymerase chain reaction. Results: The ZYQYF-H group showed significantly a lower renal weight and renal weight/body weight than the model group. The enalapril and ZYQYF-H groups showed significantly lower SBP than other groups after 6 weeks of administration. The ZYQYF-H group showed better improvement than the ZYQYF-R and enalapril groups in glomerular and tubular morphology and better reductions in inflammatory cell infiltration and collagen volumetric fraction. The ZYQYF-H group also showed better reductions in serum UA and Ang II levels; collagen-I, collagen-III, and p-Smad2/Smad-2 protein expression; and Smad-2 mRNA expression and a better increase in Smad-7 protein and mRNA expression than the enalapril group. Besides, the degree of renal function and fibrosis improvement was positively correlated with the dose of ZYQYF. Conclusion: ZYQYF can significantly reduce SHR blood pressure, protect renal function and structure, and improve renal fibrosis by regulating Smad proteins through TGF-ß1.

12.
J Org Chem ; 87(21): 14241-14249, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36219805

RESUMO

By complementing traditional transition metal catalysis, photoinduced catalysis has emerged as a versatile and sustainable way to achieve carbon-heteroatom bond formation. This work discloses a visible-light-induced reaction for the formation of a C-S bond from aryl halides and inorganic sulfuration agents via electron donor-acceptor (EDA) complex photocatalysis. Divergent formations of organic sulfide and disulfide have been demonstrated under mild conditions. Preliminary mechanistic studies suggest that visible-light-induced intracomplex charge transfer within the monosulfide-anion-containing EDA complex permits the C-S bond construction reactivity.

13.
Chaos ; 32(9): 093143, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36182353

RESUMO

This study investigates Caputo-Hadamard fractional differential equations on time scales. The Hadamard fractional sum and difference are defined for the first time. A general logarithm function on time scales is used as a kernel function. New fractional difference equations and their equivalent fractional sum equations are presented by the use of fundamental theorems. Gronwall inequality, asymptotical stability conditions, and two discrete-time Mittag-Leffler functions of Hadamard type are obtained. Numerical schemes are provided and chaos in fractional discrete-time logistic equation and neural network equations are reported.

14.
J Am Chem Soc ; 144(25): 11081-11087, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35709491

RESUMO

The recent surge in the applications of deuterated drug candidates has rendered an urgent need for diverse deuterium labeling techniques. Herein, an efficient Rh-catalyzed deuterated Tsuji-Wilkinson decarbonylation of naturally available aldehydes with D2O is developed. In this reaction, D2O not only acts as a deuterated reagent and solvent but also promotes Rh-catalyzed decarbonylation. In addition, decarbonylative strategies for the synthesis of terminal monodeuterated alkenes from α,ß-unsaturated aldehydes are within reach.


Assuntos
Ródio , Aldeídos , Alcenos , Catálise , Óxido de Deutério
15.
Front Cardiovasc Med ; 9: 854475, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35391850

RESUMO

Background: Percutaneous left atrial appendage (LAA) occlusion has been considered an efficient alternative to oral anticoagulation to prevent embolic events in patients with non-valvular atrial fibrillation (NVAF). Due to the complexities and heterogeneous anatomy of the LAA structure, the single-device approach may not always fit a large bilobulated LAA. This study aimed to evaluate the feasibility and safety of one-stop dual Watchman implantation for patients with bilobulated LAA. Methods: Included in the analysis were patients who underwent complete LAA closure with dual Watchman devices between December 2015 and December 2021. The anatomic morphology, procedure characteristics, procedure safety, and procedural complications were analyzed. Cardiac CT or transesophageal ultrasound was obtained at 7 days, 6 months, 1 year, and 2 years post-operatively to evaluate the effect of occlusion. Results: Among the 330 patients who underwent LAA occlusion during the study period, 7 (2.1%) patients were occluded with one-stop implantation of the double Watchman strategy. Successful occlusion was achieved in all patients. One patient had the double-access sheath strategy for implantation, and 6 patients had only a single-access sheath strategy for implantation. Pericardial effusion occurred in one case during the 7-day perioperative period. There was no device embolization, thrombosis, or obvious peridevice leakage (≥l mm) during the 2-year follow-up, with the exception of two cases with 2 mm of incomplete LAA sealing. Conclusion: The one-stop implantation of a dual Watchman is feasible and safe and might provide a strategy to occlude a large bilobulated LAA when incomplete closure is inevitable with a single device.

16.
Front Nutr ; 9: 1095556, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36712537

RESUMO

In this study, an effective method was developed to extract the polysaccharide from Sanghuangporus vaninii (PFSV) by destroying the cell wall. Box-Behnken design was employed to determine the optimal processing conditions as follows: processing temperature (80°C), processing time (0.81 h) and amount of HCl (1.5 ml). Under these conditions, the yield of PFSV reached 5.94 ± 0.16%. The purified polysaccharide (PFSV-2) was found to be a hetero-polysaccharide with an average molecular weight of 20.377 kDa. The backbone of PFSV-2 was composed of an →6)-α-Galp-(1→ and →2,6)-ß-Manp-(1→ and →2)-α-Fucp-(1→ and was branched of t-α-Manp-(1→ at position 2 of residue B. PFSV-2 showed hypolipidemic activity by decreasing lipid accumulation and the levels of total cholesterol and triglycerides in zebrafish larvae. Furthermore, PFSV-2 downregulated the pparg, fasn, and HMGCRb genes and upregulated the pparab and acaca genes. These findings suggested PFSV-2 may be a promising candidate in lipid regulation therapy.

17.
Nat Commun ; 12(1): 6538, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34764303

RESUMO

The Mizoroki-Heck reaction and its reductive analogue are staples of organic synthesis, but the ensuing products often lack a chemical handle for further transformation. Here we report an atom-economical cross-coupling of halopyridines and unactivated alkenes under photoredox catalysis to afford a series of alkene halopyridylation products. This protocol with mild and redox neutral conditions contributes broad substrate scope. As a complement to conventional Heck-type reaction, this radical process avoids the involvement of ß-H elimination and thus useful pyridyl and halide groups could be simultaneously and regioselectively incorporated onto alkenes. The success depends on TFA-promoted domino photocatalytic oxidative quenching activation and radical-polar crossover pathway. Plausible mechanism is proposed based on mechanistic investigations. Moreover, the reserved C - X bonds of these products are beneficial for performing further synthetic elaborations.

18.
Huan Jing Ke Xue ; 42(10): 4942-4950, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581138

RESUMO

Antibiotic residues in farmland soils resulting from the application of livestock manure poses risks to the soil and water ecology associated with the spread of antibiotic resistance, thereby threatening environmental safety and human health. Here, a leaching experiment was carried out using soil(CK-T), pig manure(PM-T), cow manure(CM-T), and chicken manure(CHM-T) with the addition of tetracyclines(tetracycline, oxytetracycline, and chlortetracycline) and a control group(without antibiotics). The effects of different sources of manure on soil physical and chemical indicators and bacterial abundance under simulated leaching conditions were studied, while the migration of tetracyclines in the different treatments were also determined. The results showed that compared with the CHM-T and CM-T treatments, the tetracyclines in the PM-T treatment were more easily accumulated in the soil(residual amounts=0.90-6.91 mg·kg-1 compared to the other treatments=0.33-4.42 mg·kg-1). Compared with the surface soil(0-4 cm), higher concentrations of tetracyclines were detected at soil depths of 16-24 cm. Consistent with the residues of antibiotics, the concentrations of TN and NH4+-N in the soil with the PM-T treatment were increased by 0.044 g·kg-1 and 14.11 mg·kg-1, respectively, which were significantly higher than other treatments. The abundance of bacteria in the soil was reduced due to the bactericidal effect of antibiotics, by 39.66% in the PM-T treatment, which was significantly higher than in the other treatments(12.38%-35.26%). Compared with other treatments, the antibiotics in the CHM-T treatment were more easily leached from the soil, with 9.91 mg of antibiotics in the leachate, which was significantly higher than the other treatments(P<0.05). TN, NH4+-N, tetracycline, oxytetracycline, and chlortetracycline were the first principal component factors, accounting for 54.55% of the variation, and corresponding concentrations increased with soil depth. Based on these results, tetracyclines in pig manure tended to accumulate in soil and transfer vertically along with variations in the soil microbial community. For chicken manure, relatively high concentrations of tetracyclines were detected in the soil leachate, increasing the risk of water pollution.


Assuntos
Esterco , Poluentes do Solo , Animais , Antibacterianos , Solo , Poluentes do Solo/análise , Suínos , Tetraciclinas/análise
20.
Micromachines (Basel) ; 12(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466564

RESUMO

The photoelectric hybrid network has been proposed to achieve the ultrahigh bandwidth, lower delay, and less power consumption for chip multiprocessor (CMP) systems. However, a large number of optical elements used in optical networks-on-chip (ONoCs) generate high transmission loss which will influence network performance severely and increase power consumption. In this paper, the Dijkstra algorithm is adopted to realize adaptive routing with minimum transmission loss of link and reduce the output power of the link transmitter in mesh-based ONoCs. The numerical simulation results demonstrate that the transmission loss of a link in optimized power control based on the Dijkstra algorithm could be maximally reduced compared with traditional power control based on the dimensional routing algorithm. Additionally, it has a greater advantage in saving the average output power of optical transmitter compared to the adaptive power control in previous studies, while the network size expands. With the aid of simulation software OPNET, the network performance simulations in an optimized network revealed that the end-to-end (ETE) latency and throughput are not vastly reduced in regard to a traditional network. Hence, the optimized power control proposed in this paper can greatly reduce the power consumption of s network without having a big impact on network performance.

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