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1.
J Colloid Interface Sci ; 643: 151-161, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37058890

RESUMO

Catalytic methane decomposition (CMD) has emerged as an appealing technology for large-scale production of H2 and carbon nanostructures from natural gas. As the CMD process is mildly endothermic, the application of concentrated renewable energy sources such as solar energy under a low-temperature regime could potentially represent a promising approach towards CMD process operation. Herein, Ni/Al2O3-La2O3 yolk-shell catalysts are fabricated using a straightforward single-step hydrothermal approach and tested for their performance in photothermal CMD. We show that the morphology of the resulting materials, dispersion and reducibility of Ni nanoparticles, and nature of metal-support interactions can be tuned by addition of varying amounts of La. Notably, the addition of an optimal amount of La (Ni/Al-20La) improved the H2 yield and catalyst stability relative to the base Ni/Al2O3 material, while also favoring base growth of carbon nanofibers. Additionally, we show for the first time a photothermal effect in CMD, whereby the introduction of 3 suns light irradiation at a constant bulk temperature of 500 °C reversibly increased the H2 yield of catalyst by about 1.2 times relative to the rate in the dark, accompanied by a decrease in apparent activation energy from 41.6 kJ mol-1 to 32.5 kJ mol-1. The light irradiation further suppressed undesirable CO co-production at low temperatures. Our work reveals photothermal catalysis as a promising route for CMD while providing an insightful understanding of the roles of modifier in enriching methane activation sites on Al2O3-based catalysts.

2.
J Colloid Interface Sci ; 591: 148-160, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33592523

RESUMO

Controlling Vacancies and heterointerfaces of nano/microstuctures is very challenging, importantly, which tailors the electromagnetic (EM) parameters to develop the high-performance electromagnetic wave (EMW) absorbers. Herein, we report a strategy using various sulfur-source modifying Fe3O4 nanosphere by one-step hydrothermal method to prepare a series of FeS2-based composites. Diverse sulfur sources determine their morphologies, crystal structures and compositions, and further affect EMW absorption abilities. Among these materials, rich sulfur vacancies and abundant heterogeneous interfaces improve their conduction loss and polarization loss caused by a unique concave cubic polyhedrons structure of the Fe3O4/FeS2 composites fabricated by thioacetamide (TAA), which displays the brilliant EMW absorption capacity compared to others. That is, it possesses the minimum reflection loss (RLmin) of -59.27 dB and effective absorption bandwidth (EAB, RL ≤ -10 dB) of 5.86 GHz at the thin thickness of 1.8 mm. This study opens a new avenue for designing the superior EMW absorbers by tunable sulfur vacancy and heterointerface.

3.
Int J Med Sci ; 17(14): 2155-2162, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922176

RESUMO

Objectives: To investigate the differences in clinical pregnancy, miscarriage, and live birth rates when male partners were diagnosed with a varicocele and to compare these outcomes to those without and study the outcomes based on the grade of varicocele. Methods: The retrospective study was based on a cohort of consecutive infertile couples undergoing assisted reproductive technology (ART) at the Reproductive Center of Shandong Provincial Hospital affiliated to the Shandong University during the period between January 2017 and December 2018. A total of 4203 couples comprised of men with and without varicocele undergoing the first ART cycle (1501 intrauterine inseminations (IUI), 1623 in vitro fertilisations (IVF) and 1079 intracytoplasmic sperm injections (ICSI)) were included. Semen parameters and ART outcomes were determined. Results: ICSI (26.5%) originated from men with a significant lower level in sperm concentration and motility but with a strict normal morphology had a higher prevalence of varicocele than men undergoing IUI (20.7%) and IVF (18.1%). In IUI, the odds ratios (ORs) for pregnancy and live birth were significantly lower for couples in men diagnosed with grades 1 or 2 varicocele as compared to those for men with grade 3 varicocele. In IVF, ORs for live birth where men were diagnosed with grades 1 or 2 varicocele were also lower than those for men with grade 3,whereas a higher miscarriage rate was found when men had grades 1 or 2 varicocele than when men had grade 3. However, for ICSI, no significant outcomes were found in grades 1, 2 or 3 varicocele versus the no varicocele group. Conclusions: The increasing grade of varicocele was negatively associated with sperm parameters and can alter the outcome of further IUI/IVF.


Assuntos
Fertilização in vitro/estatística & dados numéricos , Infertilidade Masculina/terapia , Inseminação Artificial/estatística & dados numéricos , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , Varicocele/complicações , Aborto Espontâneo/epidemiologia , Adulto , Feminino , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/etiologia , Nascido Vivo , Masculino , Gravidez , Taxa de Gravidez , Prevalência , Estudos Retrospectivos , Índice de Gravidade de Doença , Contagem de Espermatozoides , Resultado do Tratamento , Varicocele/diagnóstico , Varicocele/epidemiologia
4.
Front Genet ; 11: 143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184806

RESUMO

Congenital contractural arachnodactyly (CCA) is an extremely rare monogenic disorder in humans, and the prevalence of CCA is estimated to be less than 1 in 10,000 worldwide. CCA is characterized by arachnodactyly, camptodactyly, the contracture of major joints, scoliosis, pectus deformities, and crumpled ears. Mutations in FBN2 (which encodes fibrillin-2) are responsible for causing this disease. A family with CCA was investigated in this study, and a novel variant, c.3724+3A > C (also identified as IVS28+3A > C), in FBN2 was found in nine patients from the family but was not found in seven unaffected relatives. Reverse transcription-PCR (RT-PCR) and complementary DNA (cDNA) sequencing data showed that exon 28 was skipped in the FBN2 gene. The FBN2 c.3724+3A > C variant led to an in-frame deletion during transcription, which eventually triggered CCA in the Chinese family.

5.
Chem Rec ; 20(2): 102-119, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31250979

RESUMO

Multi-shelled hollow spheres metal oxides, namely materials with more than three shells, have attracted increasing attention due to their unique structure. The preparation methods of typical metal oxides including NiO, Co3 O4 and ZnO etc. have been summarized in this review. Simultaneously, the parameters that influence the ultimate morphologies, shell number as well as the compositions have also been discussed. The potential application fields in energy conversion and storage, electromagnetic wave absorption, photocatalysis that related to the unique structure are also highlighted. Finally, the future researches of multi-shelled hollow spheres metal oxides are further discussed.

6.
Environ Technol ; 41(23): 3105-3118, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30896338

RESUMO

ABSTRACT Coal refuse pile fires are a serious health, safety, and environment hazard. The fires in Guoshan Coal Refuse Pile affect daily life of the local residents. Although conventional fire control methods (water injection, grouting and surface sealing) were used to control the fires, they rekindled soon after the fire-fighting engineering was quitted. Thus, effective methods need to be applied to extinguish the fires completely without reignition. In this paper, the environmental impact of the fire on the local land, water and air is illustrated by sample analysis and photos. The self-potential method, which achieves remote detection from the ground surface, is adopted to delineate the scope of the fires to give support for the efficient and economical extinguishment of them. The three-phase foam containing water, gas and loess is proposed to control and extinguish the fires. The corresponding fire-fighting system is also invented to fit the field work and put out the fires more efficiently and conveniently. The temperature monitoring result shows that the fires are extinguished successfully with no sign of reignition.


Assuntos
Minas de Carvão , Incêndios , Resíduos de Alimentos , China , Carvão Mineral/análise
7.
J Nanosci Nanotechnol ; 20(5): 3140-3147, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635658

RESUMO

Platinum (Pt) has been intensively studied as an effective cocatalyst for photocatalysis, but most reports have focused on metallic Pt rather than PtO. Here, Pt/PtO nanodots were deposited on porous yolk-shell La2O3 microspheres. XRD patterns and XPS analysis demonstrated the coexistence of Pt and PtO, which was beneficial for photocatalytic performance. SEM images showed the yolk-shell structure of La2O3, and TEM images demonstrated that the Pt/PtO nanodots were uniformly distributed on the La2O3 microspheres. The rate constant of the hybrid was calculated to be 0.00656 min-1 for methyl orange (MO) degradation, while that of bare La2O3 was only 0.00303 min-1. This work suggests that the use of the deposited cocatalyst Pt/PtO on La2O3 microspheres is a promising strategy for the degradation of organic pollutants.

8.
Am J Mens Health ; 13(3): 1557988319852018, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31106684

RESUMO

To investigate the correlation of prostatic calculi (PC) with semen parameters in men with fertility intention, this retrospective case-control study enrolled 1,303 participants ranging from 20 to 59 years old; 725 were diagnosed with PC using abdominal ultrasonography. Patients with PC were classified into the type A calculi group (discrete and small echoes) and type B calculi group (coarse and large masses of multiple echoes). Five hundred and seventy-eight men without PC were recruited for the control group. The clinical data of each group were collected and analyzed. The total motility was significantly lower for subjects with type B calculi (41.84% ± 17.50%) than for subjects in the type A calculi (51.78% ± 20.84%; p < .001) and control (54.47% ± 20.74%; p < .001) groups. The percentage of progressively motile was significantly lower for the type B calculi (31.66% ± 14.68%) group than the type A calculi (40.17% ± 17.09%; p < .001) and control (41.83% ± 17.05%; p < .001) groups. The results of the hypo-osmotic swelling test yielded significantly lower percentages in the type B calculi group (59.88% ± 17.13%) than the type A calculi (65.28 ± 14.43%; p = .005) and control (66.92 ± 16.12%; p < .001) groups. The type B calculi group had a significantly higher percentage of round cell concentration than control (4.5% vs. 1.0%; p = .007) did. Small and discrete PC may not influence semen quality among adult men with fertility intention, but larger and coarser PC are associated with decreased sperm motility.


Assuntos
Cálculos/diagnóstico por imagem , Doenças Prostáticas/diagnóstico por imagem , Análise do Sêmen , Ultrassonografia/métodos , Adulto , Estudos de Casos e Controles , Hormônios/sangue , Humanos , Infertilidade Masculina/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Asian J Androl ; 21(5): 473-477, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719984

RESUMO

Antisperm antibodies (ASAs) are assumed to be a possible causative factor for male infertility, with ASAs detected in 5%-15% of infertile men but in only 1%-2% of fertile ones. It remains unclear whether ASAs have an adverse effect on the outcome of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). This study investigated differences in the rates of fertilization, pregnancy, and live births associated with serum ASA-positive and ASA-negative men following IVF or ICSI. Five hundred and fifty-four consecutive infertile couples undergoing IVF (n = 399) or ICSI (n = 155) were included. The two-sample two-sided t-test and Chi-square or Fisher's exact test was used for statistical analysis. Lower rates of fertilization (41.7% vs 54.8%, P = 0.03), good embryos (18.9% vs 35.2%, P = 0.00), pregnancy (38.5% vs 59.4%, P = 0.00), and live births (25.8% vs 42.5%, P = 0.00) were observed in men of the IVF group with a positive serum ASA than in those with a negative ASA. ASA positivity/negativity correlated with pregnancy rates (P = 0.021, odds ratio [OR]: 0.630, 95% confidence interval [CI]: 0.425-0.932) and live birth rates (P = 0.010, OR: 1.409, 95% CI: 1.084-1.831) after controlling for the female serum follicle-stimulating hormone level and the couple's ages at IVF. Women coupled with ASA-positive men had lower live birth rates with IVF than with ICSI (25.8% and 47.4%, respectively; P = 0.07). Women coupled with ASA-positive men had lower rates of pregnancy and live births following IVF than those coupled with ASA-negative men but had a similar outcome with ICSI.


Assuntos
Anticorpos/farmacologia , Fertilização in vitro/métodos , Infertilidade Masculina/imunologia , Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/imunologia , Adulto , Estudos de Coortes , Feminino , Fertilização , Humanos , Nascido Vivo , Masculino , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Resultado do Tratamento , Adulto Jovem
10.
Urology ; 84(4): 815-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25129542

RESUMO

OBJECTIVE: To investigate the association between testicular microlithiasis (TM) and semen parameters in Chinese adult men with fertility intention. MATERIALS AND METHODS: We retrospectively reviewed the ultrasonography results of the reproductive system of 16,204 consecutive adult male patients in our hospital with fertility intention from November 2012 to October 2013. TM was diagnosed by scrotal ultrasonography. Patients with TM were divided into classic testicular microlithiasis (CTM) or limited testicular microlithiasis (LTM). The clinical data of CTM, LTM, and non-TM groups, especially of patients in whom sperms were found in semen analysis, were collected and analyzed. RESULTS: There were 226 men (1.39%) diagnosed with TM. The mean age was 28.96 ± 5.12 years (range, 21-46 years), whereas mean testicular volume was 15.38 ± 4.90 mL (range, 1.62-31.23 mL). CTM and LTM were detected in 141 (62.39%) and 85 patients (37.61%), respectively. Among 200 patients who underwent semen analysis, sperms were found in 159 men (79.5%; 97 men with CTM and 62 men with LTM). One hundred and twenty cases without TM (ie, non-TM group) were collected in the control group. Sperm concentration, total motility, and percentage of progressively motile of CTM, LTM, and non-TM groups was (38.01 ± 31.58 million/mL vs 52.31 ± 33.26 million/mL vs 67.16 ± 36.94 million/mL; P <.001), (46.03 ± 23.69% vs 55.37 ± 24.16% vs 62.08 ± 20.45%; P <.001), and (35.88 ± 20.17% vs 43.15 ± 21.08% vs 47.10 ± 17.84%; P <.001), respectively. CONCLUSION: TM is associated with worse semen parameters in adult men with fertility intention. The extent of microlithiasis correlates inversely with semen parameters.


Assuntos
Cálculos/diagnóstico por imagem , Análise do Sêmen , Doenças Testiculares/diagnóstico por imagem , Adulto , Povo Asiático , Cálculos/complicações , Humanos , Infertilidade Masculina/diagnóstico por imagem , Infertilidade Masculina/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doenças Testiculares/complicações , Ultrassonografia , Adulto Jovem
11.
Fertil Steril ; 101(5): 1255-60, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24559724

RESUMO

OBJECTIVE: To evaluate intracytoplasmic sperm injection (ICSI) results with regard to congenital bilateral absence of vas deferens (CBAVD) versus non-CBAVD obstruction, cystic fibrosis transmembrane-conductance regulator (CFTR) mutations versus non-CFTR mutations, and miscarriages or stillbirths versus live births per embryo transferred. DESIGN: Retrospective study with detailed chart review. SETTING: Center for reproductive medicine. PATIENT(S): Nine hundred forty-five men with obstructive azoospermia. INTERVENTION(S): One thousand four hundred fourteen ICSI cycles classified as CBAVD versus non-CBAVD obstruction, CFTR mutations versus non-CFTR mutations, and miscarriages/stillbirths versus live births per embryo transferred. MAIN OUTCOME MEASURE(S): Frequency of CFTR mutations and rates of fertilization, good embryos, clinical pregnancy, miscarriages and stillbirths, ectopic pregnancy, and live births. RESULT(S): CFTR mutations were more prevalent in men with CBAVD than in those with non-CBAVD obstruction. The rate of miscarriages and stillbirths per embryo transferred was higher in men with CBAVD than in those with non-CBAVD obstruction, whereas the rate of live births per embryo transferred was lower in men with CBAVD than in those with non-CBAVD obstruction. The rate of miscarriages and stillbirths per embryo transferred was higher in men with CFTR mutations than in those with non-CFTR mutations. The frequency of CFTR mutations was higher in patients who experienced miscarriages/stillbirths than in those with live births. CONCLUSION(S): The frequency of CFTR mutations was higher in cases of CBAVD versus non-CBAVD obstruction. Possibly as a result of CFTR mutations, patients with CBAVD had a significantly increased risk of miscarriage and stillbirth and a reduced rate of live birth compared with patients with non-CBAVD.


Assuntos
Azoospermia/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Doenças Urogenitais Masculinas/genética , Mutação/genética , Taxa de Gravidez/tendências , Injeções de Esperma Intracitoplásmicas/tendências , Ducto Deferente/anormalidades , Adulto , Azoospermia/terapia , Feminino , Humanos , Masculino , Doenças Urogenitais Masculinas/terapia , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
12.
Urology ; 82(4): 824-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23953609

RESUMO

OBJECTIVE: To investigate cystic fibrosis transmembrane conductance regulator (CFTR) gene in Chinese men with congenital bilateral absence of vas deferens (CBAVD) and other obstructive azoospermia. MATERIALS AND METHODS: Four hundred one patients with obstructive azoospermia were included. Patients were grouped as 158 with CBAVD and 243 with other acquired obstructive azoospermia. Another 200 fertile men were used as controls. Genomic deoxyribonucleic acid was isolated from peripheral blood lymphocytes for all men. The exon 10 and 11 CFTR genes were amplified and sequenced. The frequency of CFTR gene mutations was compared among 3 groups. RESULTS: Six heterozygous mutations (+/-), I556V, M469V, E527N, F508del, S485C, and I558S, were found in 30 patients, and 1 homozygous mutation (+/+), I556V, was found in 1 patient. The overall frequency of CFTR mutations was 31 of 401 (7.7%). Of these mutations, I556V was the most common type with 24 of 31 (77.4%). In CBAVD group, 20 of 158 patients were identified with 6 different heterozygous mutations (I556V, M469V, E527N, F508del, S485C, and I558S) and 1 homozygous mutation (I556V). The rate of CFTR mutations was 12.7%. In acquired obstructive group, 11 of 243 patients were identified with 2 different heterozygous mutations, I556V and M469V; the rate of mutations was 4.5%. No CFTR mutations were identified in controls. There was significant difference among 3 groups (P = .000). The frequency of CFTR mutations in CBAVD is 2-fold higher than in other acquired obstructive group. CONCLUSION: Different CFTR mutations are observed in Chinese patients with CBAVD. I556V is the major common type of CFTR mutations in Chinese patients with CBAVD.


Assuntos
Azoospermia/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Ducto Deferente/anormalidades , Adulto , Povo Asiático , Humanos , Masculino , Mutação , Adulto Jovem
13.
Zhonghua Nan Ke Xue ; 16(10): 919-21, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21243757

RESUMO

OBJECTIVE: To explore the use of L-carnitine before percutaneous epididymal sperm aspiration-intracytoplasmic sperm injection (PESA-ICSI) in the treatment of obstructive azoospermia. METHODS: Seventy-nine cases of obstructive azoospermia treated in our center from Sep 2008 to Aug 2009 were divided into an L-carnitine (n = 43) and a control group (n = 36), the former given oral L-carnitine at 1 g bid for 3 months before PESA-ICSI, while the latter left untreated. Comparisons were made between the two groups in the number of retrieved oocytes and fertilized oocytes as well as the number and rate of good embryos. RESULTS: There were no significant differences between the two groups in the number of retrieved oocytes and fertilized oocytes. But the number and rate of good embryos were significantly higher in the L-carnitine than in the control group (P < 0.05). CONCLUSION: Three-month oral medication of L-carnitine before PESA-ICSI can raise the number and rate of good embryos in obstructive azoospermia patients and therefore benefit the therapeutic outcome.


Assuntos
Azoospermia/terapia , Carnitina/uso terapêutico , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Carnitina/administração & dosagem , Epididimo , Humanos , Masculino , Resultado do Tratamento
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