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1.
Article in English | MEDLINE | ID: mdl-38729293

ABSTRACT

Steroidogenic acute regulatory protein (Star) plays an essential role in the biosynthesis of corticosteroids and sex steroids by mediating the transport of cholesterol from the outer to the inner membrane of mitochondria. Two duplicated Star genes, namely star1 and star2, have been identified in non-mammalian vertebrates. To investigate the roles of star genes in fish steriodogenesis, we generated two mutation lines of star1-/- and star1-/-/star2-/- in Nile tilapia (Oreochromis niloticus). Previous studies revealed that deficiency of star2 gene caused delayed spermatogenesis, sperm apoptosis and sterility in male tilapia. Our present data revealed that mutation of star genes impaired male fertility. Disordered seminiferous lobules and spermatic duct obstruction were found in the testis of both types of mutants. Moreover, significant decline in semen volume, sperm abnormality and impaired fertility were also detected in star1-/- and star1-/-/star2-/- males. In star1-/- male fish, lipid accumulation, up-regulation of steroidogenic enzymes, and significant decline of androgens were found. Additionally, hyperplasic interrenal cells, elevated steroidogenic gene expression level and decline of serum glucocorticoids were detected in star1 mutants. Intriguingly, either 11-KT or cortisol supplementation successfully rescued the impaired fertility of the star1-/- mutants. Taken together, these results further indicate that Star1 might play critical roles in the production of both 11-KT and glucocorticoids, which are indispensable for the maintenance of male fertility in fish.


Subject(s)
Cichlids , Fertility , Glucocorticoids , Mutation , Phosphoproteins , Testosterone , Animals , Male , Cichlids/genetics , Cichlids/metabolism , Testosterone/metabolism , Testosterone/blood , Testosterone/analogs & derivatives , Fertility/genetics , Phosphoproteins/genetics , Phosphoproteins/metabolism , Glucocorticoids/metabolism , Fish Proteins/genetics , Fish Proteins/metabolism , Testis/metabolism
3.
Front Endocrinol (Lausanne) ; 13: 1074921, 2022.
Article in English | MEDLINE | ID: mdl-36523590

ABSTRACT

Background: Steroid hormones play an essential role in many reproductive processes of vertebrates. Previous studies revealed that teleost-specific Cyp17a2 (cytochrome P450 family 17 subfamily a 2) might be required for the production of cortisol in the head-kidney and 17α,20ß-dihydroxy-4-pregnen-3-one (DHP) in ovary during oocyte maturation. However, the role of Cyp17a2 in male reproduction remains to be largely unknown. The aim of this study was to explore the essentiality of cyp17a2 gene in male steroidogenesis, spermatogenesis, and male fertility. Methods: A homozygous mutation line of cyp17a2 gene was constructed in tilapia by CRISPR/Cas9 gene editing technology. The expression level of germ cell and meiosis-related genes and steroidogenic enzymes were detected by qRT-PCR, IHC, and Western blotting. EIA and LC-MS/MS assays were used to measure the steroid production levels. And sperm quality was examined by Sperm Quality Analyzer software. Results: In this study, cyp17a2 gene mutation resulted in the significant decline of serum DHP and cortisol levels. On the contrary, significant increases in intermediate products of cortisol and DHP were found in cyp17a2-/- male fish. The deficiency of cyp17a2 led to the arrest of meiotic initiation in male fish revealing as the reduction of the expression of germ cell-related genes (vasa, piwil, oct4) and meiosis-related genes (spo11 and sycp3) by 90 dah. Afterwards, spermatogenesis was gradually recovered with the development of testis in cyp17a2-/- males, but it showed a lower sperm motility and reduced fertility compared to cyp17a2+/+ XY fish. Deletion of cyp17a2 led to the abnormal upregulation of steroidogenic enzymes for cortisol production in the head-kidney. Moreover, unaltered serum androgens and estrogens, as well as unchanged related steroidogenic enzymes were found in the testis of cyp17a2-/- male fish. Conclusion: This study proved that, for the fist time, Cyp17a2 is indispensable for cortisol and DHP production, and cyp17a2 deficiency associated curtailed meiotic initiation and subfertility suggesting the essentiality of DHP and cortisol in the male fertility of fish.


Subject(s)
Cichlids , Animals , Female , Male , Cichlids/metabolism , Chromatography, Liquid , Hydrocortisone/metabolism , Sperm Motility , Semen , Tandem Mass Spectrometry , Fertility
4.
Int J Gen Med ; 15: 7249-7264, 2022.
Article in English | MEDLINE | ID: mdl-36124104

ABSTRACT

Background: Post-stroke cognitive impairment (PSCI) is one of the most common complications after stroke. In recent years, as a complementary alternative therapy, many systematic reviews (SRs) and meta-analysis (MAs) have reported the efficacy and safety of acupuncture in improving cognitive function in patients with PSCI, but the quality of evidence is unknown and therefore needs to be evaluated comprehensively. Aim: We aimed to evaluate the SRs of acupuncture for patients with PSCI, to summarize the evidence quality of SRs to provide scientific evidence. Methods: We searched for relevant SRs and MAs in seven databases up to March 22, 2022. Two reviewers independently completed literature retrieval, screening, and data extraction. We used A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) to evaluate the methodological quality; the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool to determine the strength of evidence; and the ROBIS tool to assess RoB. Results: We identified 14 SRs. The methodological quality of all SRs was low (2/14) or very low (12/14). GRADE results showed 13 were moderate quality (26%), 5 were low quality (10%), and 32 were very-low quality (64%). RoB showed that one SR had a low risk and 13 had a high risk. Moderate quality results showed that combined acupuncture therapy was superior to western medicine or cognitive rehabilitation training in improving cognitive function, the total response rate, and the daily living ability of patients with PSCI. Conclusion: Based on the evidence, acupuncture appears to be effective and safe in improving cognitive function for patients with PSCI, but the overall quality of SRs is not high. High-quality randomized controlled trials are needed to confirm the effectiveness and safety of acupuncture on the cognitive function of patients with PSCI. Systematic Review Registration: PROSPERO CRD42022315441.

5.
Front Pharmacol ; 13: 883729, 2022.
Article in English | MEDLINE | ID: mdl-36034818

ABSTRACT

Background: At present, a number of systematic reviews (SRs) on Xuebijing injection (a patent in China) in the treatment of acute pancreatitis (AP) or severe acute pancreatitis (SAP) have been published. However, the quality of evidence is uneven and has not been comprehensively evaluated. Aim: We evaluated the efficacy of Xuebijing injection for AP/SAP through an overview of SR, and to provide a scientific basis for its effectiveness and safety. Methods: We searched Cochrane Library, Embase, PubMed, SinoMed, CNKI, Wanfang, and VIP comprehensively. The retrieval period from inception to 30 November 2021, and the two reviewers independently complete the literature retrieval, data extraction and evaluation. The Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2) and the Preferred Reporting Item for Systematic Review and Meta-analysis (PRISMA) were used to evaluate the methodological quality and reporting quality of the SRs, respectively. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was used to evaluate the quality grading of outcomes and the risk of bias in SRs was evaluated by ROBIS Tool. Finally, the RCTs involved in SRs were synthesized. Stata15.1 was used for quantitative analysis of total effectiveness rate, time until relief of abdominal pain, time until relief of abdominal distension, and serum amylase level. Results: Nine eligible SRs were included, including 92 RCTs and 6,837 participants. The quality of SRs was relatively good, and the manuscript structures were relatively complete. However, the methodological quality of SRs was low or critically low. RoB rated 5 SRs as low risk of bias and 4 SRs as high risk of bias. In GRADE, a total of 47 results were included in the 9 SRs, of which 5 results (10.64%) were moderate quality, 22 results (46.81%) were low quality, and 20 results (42.55%) were very low quality. The results of data synthesis showed that Xuebijing injection combined treatment increased the total effectiveness rate of AP patients (RR = 1.19, 95% CI 1.17-1.23, p < 0.0001), and there was no heterogeneity between studies (I2 = 0.0%, p = 0.589). Compared with the control group, Xuebijing injection group shortened the abdominal pain and distension relief time in AP patients (WMD = -1.69, 95% CI -1.88--1.50, p < 0.0001; WMD = -1.48, 95% CI -1.74--1.23, p < 0.0001), with high heterogeneity (I2 = 84.3%, p = 0.000; I2 = 72.2%, p = 0.000). Serum amylase level was also reduced (WMD = -2.06, 95% CI -2.47--1.64, p < 0.0001), with significant heterogeneity (I2 = 71.6%, p = 0.000). A total of one SR reported adverse drug reaction (ADR), no ADRs were observed in the control group. Conclusion: Although the quality of the evidence is not high, it can still reflect the clinical value of Xuebijing injection as an analgesic and anti-inflammatory traditional Chinese medicine in the treatment of AP/SAP. Therefore, future clinical studies should focus on the long-term efficacy and adverse reactions of drugs. Systematic Review Registration: (website), identifier (registration number).

6.
Front Psychiatry ; 12: 786401, 2021.
Article in English | MEDLINE | ID: mdl-34925110

ABSTRACT

Background: Clinical evidence suggests that acupuncture is effective for relieving abdominal pain and distension in acute pancreatitis (AP). However, there is a lack of systematic reviews and meta-analyses that provide high-quality evidence of the efficacy and safety of acupuncture in this context. Aim: To assess the efficacy and safety of acupuncture for relieving abdominal pain and distension in AP. Methods: We searched the PubMed, Web of Science, Embase, Cochrane Library, CNKI, Wanfang, VIP, and China Biomedical Literature databases. Randomized controlled trials of acupuncture plus routine treatment (RT) vs. RT alone or RT plus sham/placebo acupuncture were included. Primary outcomes included total effectiveness rate, VAS scores for abdominal pain and distension, and time until relief of abdominal pain and distension. Secondary outcomes included time until recovery of bowel sound, time until first defecation, length of hospital stay, and APACHE II score. Results: Nineteen eligible original studies (n = 1,503) were included. The results showed that acupuncture in combination with RT had a significant advantage in terms of increasing the total effectiveness rate [risk ratio: 1.15; 95% confidence interval (CI): 1.06-1.24; P = 0.001]. Acupuncture also reduced the VAS score for abdominal pain [weighted mean difference (WMD): -1.45; 95% CI: -1.71 to -1.19; P < 0.0001] and the VAS score for abdominal distension (WMD: -0.71; 95% CI: -1.04 to -0.37; P < 0.0001) in patients with AP. Other results also showed the efficacy of acupuncture. One study reported adverse events after acupuncture. Conclusion: Acupuncture in combination with RT has a better effect than RT alone for relieving abdominal pain and distension in AP. More rigorous studies are needed to confirm this result. Systematic Review Registration: PROSPERO CRD42019147503 (https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=147503).

7.
Ann Palliat Med ; 10(10): 11148-11155, 2021 10.
Article in English | MEDLINE | ID: mdl-34763474

ABSTRACT

BACKGROUND: Heart failure (HF) is the final stage of cardiovascular disease development, and clinical studies on acupuncture for the treatment of HF are increasing. However, the efficacy and safety of these acupuncture methods are unclear. The purpose of this study is to conduct a meta-analysis of the relevant randomized controlled trials (RCTs) to explain their efficacy and safety through high-quality evidence. METHODS: The databases of the Cochrane Library, PubMed, Web of Science, SinoMed, China National Knowledge Infrastructure (CNKI), Wan-fang, and VIP will be searched from inception date to June 2021. The search will not be restricted by language. This study will include RCTs of various acupuncture methods for HF. Study selection, data extraction, and research quality assessments will be conducted independently by two researchers. The primary outcome is the efficacy rate and heart function, the secondary outcomes are quality of life scores, rehospitalization, and adverse reactions/events. The software RevMan 5.3 and Aggregate Data Drug Information System (ADDIS) will be used for network meta-analysis (NMA). Risk of bias, meta-regression, subgroup analysis, and sensitivity analysis will be performed, and the quality of evidence will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. DISCUSSION: This study will confirm the efficacy and safety of acupuncture in improving the clinical symptoms and heart function of HF, or elucidate which method of acupuncture is better suited to this purpose.


Subject(s)
Acupuncture Therapy , Heart Failure , China , Heart Failure/therapy , Humans , Meta-Analysis as Topic , Network Meta-Analysis , Randomized Controlled Trials as Topic , Research Design , Systematic Reviews as Topic
8.
Endocrinology ; 162(12)2021 12 01.
Article in English | MEDLINE | ID: mdl-34581801

ABSTRACT

In teleost fish, sex steroids are involved in sex determination, sex differentiation, and fertility. Cyp17a1 (Cytochrome P450 family 17 subfamily A member 1) is thought to play essential roles in fish steroidogenesis. Therefore, to further understand its roles in steroidogenesis, sex determination, and fertility in fish, we constructed a cyp17a1 gene mutant in Nile tilapia (Oreochromis niloticus). In XX fish, mutation of the cyp17a1 gene led to a female-to-male sex reversal with a significant decline in 17ß-estradiol (E2) and testosterone (T) production, and ectopic expression of male-biased markers (Dmrt1 and Gsdf) in gonads from the critical window of sex determination. Sex reversal was successfully rescued via T or E2 administration, and ovarian characteristics were maintained after termination of E2 supplementation in the absence of endogenous estrogen production in cyp17a1-/- XX fish. Likewise, deficiencies in T and 11-ketotestosterone (11-KT) production in both cyp17a1-/- XX sex-reversed males and cyp17a1-/- XY mutants resulted in meiotic initiation delays, vas deferens obstruction and sterility due to excessive apoptosis and abnormal mitochondrial morphology. However, 11-KT treatment successfully rescued the dysspermia to produce normal sperm in cyp17a1-/- male fish. Significant increases in gonadotropic hormone (gth) and gth receptors in cyp17a1-/- mutants may excessively upregulate steroidogenic gene expression in Leydig cells through a feedback loop. Taken together, our findings demonstrate that Cyp17a1 is indispensable for E2 production, which is fundamental for female sex determination and differentiation in XX tilapia. Additionally, Cyp17a1 is essential for T and 11-KT production, which further promotes spermatogenesis and fertility in XY males.


Subject(s)
Cichlids/physiology , Cytochrome P450 Family 17/physiology , Gonadal Steroid Hormones/biosynthesis , Infertility, Male/genetics , Sex Determination Processes/genetics , Animals , Animals, Genetically Modified , Cichlids/genetics , Cichlids/metabolism , Cytochrome P450 Family 17/genetics , Female , Fertility/genetics , Fishes/physiology , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Infertility, Male/veterinary , Male , Metabolic Networks and Pathways/genetics
9.
J Steroid Biochem Mol Biol ; 197: 105517, 2020 03.
Article in English | MEDLINE | ID: mdl-31678357

ABSTRACT

The essential roles of Relaxin3 (RLN3) in energy homeostasis had been well investigated, while the mechanisms of RLN3 regulating reproduction remain to be elusive in mammals. Although two rln3 paralogues have been characterized in several teleosts, their functions still remain largely unknown. In this study, two paralogous rln3 genes, represented as rln3a and rln3b, were identified from the testis of Nile tilapia (Oreochromis niloticus). Rln3a was dominantly expressed in testis, while the most abundant rln3b expression was in brain. In situ hybridization demonstrated that rln3a is abundantly expressed in the Leydig cells of the testis. To understand the role of Rln3 in the testicular development, homologous null-rln3a gene mutant line was constructed by CRISPR/Cas9 technology. Morphological observation demonstrated that null mutation of rln3a gene caused testicular hypertrophy and a significant increase of GSI. However, a significant decrease of spermatogenic cells at different phases, i.e. spermatogonia, spermatocytes, spermatids and sperms was found. Silencing of rln3a gene repressed the expression of key genes in germ cell and Leydig cell. Deficiency of Rln3a led to the significant decrease of 11-KT production, which stimulated the up-regulation of both FSH and LH production in the pituitary via a negative feedback manner possibly. Mutation of rln3a in XY fish led to the hypogonadism with sperm deformation, significant decrease of fertility, and sperm motility, revealing as the high mortality of the offspring obtained by crossing the wild type female and rln3a-/- XY fish. Interestingly, recombinant human RLN3 injection significantly enhanced the sperm motility in rln3a-/- XY fish. Moreover, hCG treatment stimulated the expression of steroidogenic enzyme genes and 11-KT production, which were repressed by rln3a mutation in XY fish. Taken together, this study, for the first time by using a gene knockout model, proved that Rln3a is an indispensable mediator for androgen production in testis via HPG axis, and plays an essential role in spermatogenesis, sperm motility and male fertility in fish.


Subject(s)
Cichlids/growth & development , Fertility , Relaxin/metabolism , Spermatogenesis , Testis/growth & development , Amino Acid Sequence , Animals , CRISPR-Cas Systems , Cichlids/genetics , Cichlids/metabolism , Male , Mutation , Phylogeny , Relaxin/antagonists & inhibitors , Relaxin/genetics , Sequence Homology , Sperm Motility , Testis/metabolism
10.
Anat Rec (Hoboken) ; 302(6): 861-868, 2019 06.
Article in English | MEDLINE | ID: mdl-30315688

ABSTRACT

Nissl and immunohistochemical staining methods were used to morphologically characterize the cerebellum of the new-hatching Yangtze alligator, and the cerebellar histological structure and the distribution profiles of 5-hydroxytryptamine (5-HT) and dopamine (DA) neurons were investigated for the first time. The results of cerebellar histological structure showed that there was a ventriculus cerebelli in the cerebellum of the new-hatching Yangtze alligator, the surface of the cerebellar cortex was not very smooth, the cerebellar cortex could be divided into four layers, which include external granular layer, molecular layer, Purkinje cell layer and granular layer, Purkinje cell layer could be characterized specially by multilayer, two cerebellar nuclei termed as the nucleus cerebelli lateralis and the nucleus cerebelli medialis were found in the cerebellar medulla. 5-hydroxytryptamine-immunoreactive (5-HT-IR) and dopamine-immunoreactive (DA-IR) neurons and fibers distributed widely in the cerebellum. The structures and profiles of 5-HT-IR and DA-IR neurons and fibers in the cerebellum of the Yangtze alligator were similar to that reported in other reptiles, but also had some specific features. The abundance of 5-HT and DA in cerebellum suggested that these highly conserved neurotransmitters would play important roles in motor control. Anat Rec, 302:861-868, 2019. © 2018 Wiley Periodicals, Inc.


Subject(s)
Alligators and Crocodiles/physiology , Cerebellar Cortex/cytology , Dopaminergic Neurons/physiology , Motor Activity/physiology , Serotonergic Neurons/physiology , Animals , Animals, Newborn , Cerebellar Cortex/physiology , Dopamine/metabolism , Serotonin/metabolism
11.
J Steroid Biochem Mol Biol ; 182: 62-71, 2018 09.
Article in English | MEDLINE | ID: mdl-29705270

ABSTRACT

It was documented that 17α, 20ß-dihydroxy-4-pregnen-3-one (DHP), a fish specific progestin, might play critical roles in spermatogenesis, sperm maturation and spermiation partially through activating nuclear receptor (Pgr). However, no direct evidence is available to demonstrate the functions of DHP in fish spermatogenesis. To further elucidate the roles of DHP in teleosts, we generated a pgr homozygous mutant line in XY Nile tilapia (Oreochromis niloticus). Pgr gene mutation resulted in the development of a smaller, thinner testis and a lower GSI compared with normal testis. Pgr gene knockout led to irregular arrangement of spermatogenic cysts, decline of sperm count and sperm motility. Significant decrease of spermatocytes and spermatozoa was observed, which was further proved by the PCNA and Ph3 staining. Real-time PCR analysis demonstrated that mutation of pgr gene resulted in a significant up-regulation of steroidogenesis-related genes of cyp17a, cyp11b2, StAR, scc, 20ß-HSD, and sf1, and down-regulation of fshb, fshr, oct4, sycp3, cdk1, prm, cyclinB1, cyclinB2 and cdc25 genes. Furthermore, both Immunohistochemistry and Western blotting experiments revealed a remarkable increase of Cyp17a1, Cyp17a2 and Cyp11b2 expressions in the pgr-/- testis. EIA measurement showed that an evident increase of 11-KT level was found in the pgr-/- XY fish. There was a significant increase in the mortality of offspring when crossing pgr-/- XY fish with wild type XX fish. Increased TUNEL staining and enhanced apoptosis maker gene (bax) expressions were also observed. Taken together, our data suggested that DHP-activated physiology via pgr is crucial for the fertility in the XY tilapia.


Subject(s)
Fish Proteins/metabolism , Gene Expression Regulation, Developmental , Infertility/etiology , Receptors, Progesterone/antagonists & inhibitors , Sperm Motility , Spermatogenesis , Animals , Apoptosis , CRISPR-Cas Systems , Cichlids , Fish Proteins/genetics , Infertility/pathology , Male , Mutation , Progestins/pharmacology , Receptors, Progesterone/genetics , Sertoli Cells/drug effects , Sertoli Cells/metabolism , Sertoli Cells/pathology
12.
Sci Rep ; 6: 38855, 2016 12 12.
Article in English | MEDLINE | ID: mdl-27941857

ABSTRACT

The hydrate structure type and dissociation behavior for pure methane and methane-ethane hydrates at temperatures below the ice point and atmospheric pressure were investigated using in situ Raman spectroscopic analysis. The self-preservation effect of sI methane hydrate is significant at lower temperatures (268.15 to 270.15 K), as determined by the stable C-H region Raman peaks and AL/AS value (Ratio of total peak area corresponding to occupancies of guest molecules in large cavities to small cavities) being around 3.0. However, it was reduced at higher temperatures (271.15 K and 272.15 K), as shown from the dramatic change in Raman spectra and fluctuations in AL/AS values. The self-preservation effect for methane-ethane double hydrate is observed at temperatures lower than 271.15 K. The structure transition from sI to sII occurred during the methane-ethane hydrate decomposition process, which was clearly identified by the shift in peak positions and the change in relative peak intensities at temperatures from 269.15 K to 271.15 K. Further investigation shows that the selectivity for self-preservation of methane over ethane leads to the structure transition; this kind of selectivity increases with decreasing temperature. This work provides new insight into the kinetic behavior of hydrate dissociation below the ice point.

13.
Sci Rep ; 6: 21114, 2016 Feb 19.
Article in English | MEDLINE | ID: mdl-26892255

ABSTRACT

Separation of low boiling gas mixtures is widely concerned in process industries. Now their separations heavily rely upon energy-intensive cryogenic processes. Here, we report a pseudo-absorption process for separating low boiling gas mixtures near normal temperature. In this process, absorption-membrane-adsorption is integrated by suspending suitable porous ZIF material in suitable solvent and forming selectively permeable liquid membrane around ZIF particles. Green solvents like water and glycol were used to form ZIF-8 slurry and tune the permeability of liquid membrane surrounding ZIF-8 particles. We found glycol molecules form tighter membrane while water molecules form looser membrane because of the hydrophobicity of ZIF-8. When using mixing solvents composed of glycol and water, the permeability of liquid membrane becomes tunable. It is shown that ZIF-8/water slurry always manifests remarkable higher separation selectivity than solid ZIF-8 and it could be tuned to further enhance the capture of light hydrocarbons by adding suitable quantity of glycol to water. Because of its lower viscosity and higher sorption/desorption rate, tunable ZIF-8/water-glycol slurry could be readily used as liquid absorbent to separate different kinds of low boiling gas mixtures by applying a multistage separation process in one traditional absorption tower, especially for the capture of light hydrocarbons.

14.
J Environ Manage ; 169: 167-73, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26745178

ABSTRACT

ZIF-67(zinc-methylimidazolate framework-67), one of the zeolitic imidazolate frameworks (ZIFs), was used for the removal of phenol from aqueous solutions via adsorption and shows high adsorption capacity for phenol. The thermodynamic and kinetic adsorption behavior of ZIF-67 for phenol in water with concentration ranging from 50 to 300 ppm were investigated in a batch reactor and a ZIF-67 packed column, respectively. The effects of pH, contact time, zeta potential of the adsorbent and temperature on the adsorption behavior were evaluated, and the results demonstrated that the adsorption is primarily brought about by a specific favorable interaction (electrostatic interaction) between phenol and ZIF-67 surface. The suitability of the Langmuir adsorption model to the equilibrium data was investigated for each phenol-adsorbent system, which the results showed that the equilibrium data for all the phenol-sorbent systems fitted the Langmuir model. Thermodynamic parameters such as Gibbs free energy are calculated from the experimental data at different temperatures. The adsorbent could be perfectly regenerated at 120 °C with little loss in the adsorption ability.


Subject(s)
Imidazoles/chemistry , Phenol/chemistry , Phenols/chemistry , Water Purification/methods , Zeolites/chemistry , Zinc/chemistry , Adsorption , Kinetics , Phenol/analysis , Phenols/analysis , Temperature , Thermodynamics , Water , Water Pollutants, Chemical
15.
Nat Commun ; 5: 5147, 2014 Oct 09.
Article in English | MEDLINE | ID: mdl-25296559

ABSTRACT

Removal of carbon dioxide is an essential step in many energy-related processes. Here we report a novel slurry concept that combines specific advantages of metal-organic frameworks, ion liquids, amines and membranes by suspending zeolitic imidazolate framework-8 in glycol-2-methylimidazole solution. We show that this approach may give a more efficient technology to capture carbon dioxide compared to conventional technologies. The carbon dioxide sorption capacity of our slurry reaches 1.25 mol l(-1) at 1 bar and the selectivity of carbon dioxide/hydrogen, carbon dioxide/nitrogen and carbon dioxide/methane achieves 951, 394 and 144, respectively. We demonstrate that the slurry can efficiently remove carbon dioxide from gas mixtures at normal pressure/temperature through breakthrough experiments. Most importantly, the sorption enthalpy is only -29 kJ mol(-1), indicating that significantly less energy is required for sorbent regeneration. In addition, from a technological point of view, unlike solid adsorbents slurries can flow and be pumped. This allows us to use a continuous separation process with heat integration.

16.
Opt Express ; 19 Suppl 4: A657-63, 2011 Jul 04.
Article in English | MEDLINE | ID: mdl-21747532

ABSTRACT

In this paper, Ag-Au alloy nanoparticles (NPs) were fabricated by dewetting process to enhance the broadband antireflection performance of textured silicon surfaces. The alloy NPs presented a large range of shapes and sizes, which provided an average reflectance (AR) below 4% over the spectral range of 300~1200 nm, a decrease of ~50% and ~90% as compared to the corresponding monometallic NPs and the original flat Si surfaces, respectively. The superior broadband antireflection demonstrated by the alloy NPs are attributed to the enhanced light trapping by alloy nanoparticle plasmon resonance.

17.
Opt Express ; 19(6): 5283-9, 2011 Mar 14.
Article in English | MEDLINE | ID: mdl-21445165

ABSTRACT

In this paper we present a simulation study of nanostructures with unit cells of periodic coupled cut-wire pairs for band-stop properties in the optical frequency range. A band-stop filter with a broader stop band for space transmission is realized by making use of plasmon hybridization. The bandwidth of the filter is tunable over a large range from 56.6 to 182.2 THz by magnetic and electric couplings between adjacent unit cells. An equivalent RLC resonant circuit is proposed to analyze the origin of the coupling effects. The bandwidth tunability by the coupling effect provides good guidance for a metamaterial design that works in broadband frequencies.

18.
Chin Med J (Engl) ; 123(12): 1582-8, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20819516

ABSTRACT

BACKGROUND: Previous studies with animal experiments, autopsy, structural magnetic resonance imaging (MRI) and task-related functional MRI (fMRI) have confirmed that brain functional connectivity in addicts has become impaired. The goal of this study was to investigate the alteration of resting-state functional connectivity of the ventral anterior cingulate cortex (vACC) in the heroin abusers' brain. METHODS: Fifteen heroin abusers and fifteen matched healthy volunteers were studied using vACC as the region-of interest (ROI) seed. A 3.0 T scanner with a standard head coil was the imagining apparatus. T2*-weighted gradient-echo planar imaging (GRE-EPI) was the scanning protocol. A ROI seed based correlation analysis used a SPM5 software package as the tool for all images processing. RESULTS: This study showed a functional connection to the insula vACC in heroin abusers. Compared with controls, heroin users showed decreased functional connectivity between the nucleus accumbens (NAc) and vACC, between the parahippocampala gyrus/amgdala (PHC/amygdala) and vACC, between the thalamus and vACC, and between the posterior cingulated cortex/precuneus (PCC/pC) and vACC. CONCLUSION: The altered resting-state functional connectivity to the vACC suggests the neural circuitry on which the addictive drug has an affect and reflects the dysfunction of the addictive brain.


Subject(s)
Gyrus Cinguli/pathology , Heroin Dependence/physiopathology , Adult , Female , Gyrus Cinguli/physiopathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged
19.
J Nanosci Nanotechnol ; 9(4): 2660-3, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19438017

ABSTRACT

An approach to reject stray light and improve glucose adsorption was presented. With a self-assembled monolayer (SAM) and a confocal optical configuration applied in this approach, the adsorption and signal to noise ratio (SNR) have been improved respectively. Our experimental results demonstrated that the surface enhanced Raman scattering (SERS) spectroscopy with 9 feature peaks for 100 mM aqueous glucose is successfully obtained in a dry environment in response time as fast as 40 s only. This approach could improve glucose detection in response time and sensitivity effectively in atmosphere environment.


Subject(s)
Glucose/analysis , Hexanols/chemical synthesis , Nanospheres/chemistry , Polystyrenes/chemistry , Silver/chemistry , Spectrum Analysis, Raman/methods , Sulfhydryl Compounds/chemical synthesis , Adsorption , Glucose/chemistry , Hexanols/chemistry , Spectrum Analysis, Raman/instrumentation , Sulfhydryl Compounds/chemistry , Surface Properties , Time Factors
20.
Chem Asian J ; 4(5): 754-60, 2009 May 04.
Article in English | MEDLINE | ID: mdl-19347894

ABSTRACT

Low temperature photoisomerization of stilbene and 1,4-diphenyl-1,3-butadiene derivatives was found to vary depending on the organic glass employed in such studies. Examination of the combined results showed that the variation was more likely to arise from the rigidity of the organic glass at the temperature of irradiation rather than the composition of the organic glass; that is, the observed results are consistent with the possible softening of the glass that surrounds the excited substrate in the same manner as detected in the photolysis of ethyl iodide reported by Porter and co-workers. These observations successfully account for the apparent "disagreement" of reports from the Hawaii and the Florida State groups on the mechanism of photoisomerization in low temperature glasses.

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