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1.
J Nanosci Nanotechnol ; 18(2): 1078-1082, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448536

RESUMO

A mesoporous material, Al-MCM-41, was applied to the catalytic pyrolysis of municipal plastic film waste (MPFW) to produce large amounts of valuable hydrocarbons. Compared to non-catalytic pyrolysis, the catalytic pyrolysis of MPFW over Al-MCM-41 revealed a lower decomposition temperature and activation energy upon thermogravimetric analysis. Heavy aliphatic hydrocarbons, which are the major products of non-catalytic pyrolysis, were cracked into small hydrocarbons and converted efficiently to aromatic hydrocarbons by catalytic pyrolysis over Al-MCM-41. The activity of catalytic conversion was enhanced by increasing the catalyst to reactant ratio.

2.
J Nanosci Nanotechnol ; 18(2): 1331-1335, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448585

RESUMO

The catalytic hydrodeoxygenation (HDO) of bio-oil over Ni-supported mesoporous materials was performed using a high pressure autoclave reactor. The actual pyrolysis oil of cork oak wood was used as a sample, and Ni/Al-SBA-15 and Ni/Al-MSU-F were used as catalysts. In addition, supercritical ethanol was added as solvent. Both Ni-supported mesoporous catalysts showed efficient HDO reaction ability. A higher heating value and pH of bio-oil were achieved by the HDO reaction over both catalysts and upgraded bio-oil had a lower viscosity. Compared to Ni/Al-MSU-F, Ni/Al- SBA-15 produced more upgraded bio-oil with a lower oxygen content and higher heating value via a catalytic HDO process.

3.
J Nanosci Nanotechnol ; 18(2): 1423-1426, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448604

RESUMO

The catalytic pyrolysis of two types of lignin, organosolv and klason lignin, which were extracted from miscanthus, over Al-SBA-15 was carried out using a thermogravimetric (TG) analyzer and a pyroyzer-gas chromatography/mass spectrometry (Py-GC/MS). Although Al-SBA-15 has weak acidity, the large molecular phenolic pyrolyzates of lignin were converted effectively into small molecular phenols and aromatic hydrocarbons due to the large pore size of Al-SBA-15. Compared to klason lignin, organosolv lignin produced larger amounts of valuable chemicals, such as mono-phenol, mono-aromatics, and furans, by catalytic pyrolysis over Al-SBA-15.

4.
J Nanosci Nanotechnol ; 18(2): 1492-1494, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448621

RESUMO

The removal of acetaldehyde, which is one of main components of food waste odor was investigated using biomass char as a nanoporous carbon absorbent. The biomass char adsorbent obtained from the pyrolysis of Geodae-Uksae was modified by the water and KOH treatment. The modified char absorbent had a higher acetaldehyde removal efficiency than nanoporous CMK-8 possibly due to its high oxygen and nitrogen functional groups.

5.
Chemosphere ; 350: 141121, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185423

RESUMO

The use of lignocellulosic waste as an energy source for substituting fossil fuels has attracted lots of attention, and pyrolysis has been established as an effective technology for this purpose. However, the utilization of bio-oil derived from non-catalytic pyrolysis faces certain constraints, making it impractical for direct application in advanced sectors. This study has focused on overcoming these challenges by employing fractional condensation of pyrolytic vapors at distinct temperatures. The potential of five types of sawdust for producing high-quality bio-oil through pyrolysis conducted with a bench-scale bubbling fluidized bed reactor was investigated for the first time. The highest yield of bio-oil (61.94 wt%) was produced using sample 3 (damaged timber). Remarkably, phenolic compounds were majorly gathered in the 1st and 2nd condensers at temperatures of 200 °C and 150 °C, respectively, attributing to their higher boiling points. Whereas, carboxylic acid, ketones, and furans were mainly collected in the 3rd (-5 °C) and 4th (-20 °C) condensers, having high water content in the range of 35.33%-65.09%. The separation of acidic nature compounds such as acetic acid in the 3rd and 4th was evidenced by its low pH in the range of 4-5, while the pH of liquid collected in the 1st and 2nd condensers exhibited higher pH (6-7). The well-separated bio-oil derived from biomass pyrolysis facilitates its wide usage in various applications, proposing a unique approach toward carbon neutrality. In particular, achieving efficient separation of phenolic compounds in bio-oil is important, as these compounds can undergo further upgrading to generate hydrocarbons and diesel fuel.


Assuntos
Temperatura Alta , Polifenóis , Pirólise , Biocombustíveis , Óleos de Plantas , Fenóis/análise , Biomassa
6.
Gerontology ; 56(5): 474-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20068282

RESUMO

BACKGROUND: The age-related effects on various aspects of swallowing have been reported in studies on the temporal relationship between hyolaryngeal movement and bolus location, as well as the extent of hyolaryngeal movement. However, few studies have described the temporal and spatial relationships concurrently. OBJECTIVE: The main purpose of this study was to define the kinematics of the hyoid bone and epiglottis, during swallowing, on the temporal and spatial relationships concurrently in healthy subjects, and to investigate the influence of aging on hyolaryngeal movement. METHODS: We performed a two-dimensional motion analysis of the hyoid bone and epiglottis using videofluoroscopy images in 69 normal subjects. The trajectories of the hyolaryngeal movement and passage of a bolus were superimposed to form one plot. Temporal measurements included initiation and duration of the hyoid bone and epiglottis movement compared to their movement with the bolus. The spatial measurements included vertical and horizontal excursion of the hyoid bone, and the rotational angle of the epiglottis. RESULTS: The duration of supraglottis closure, and the maximal vertical excursion of the hyoid bone were increased in older subjects, more than 65 years of age, compared to younger subjects (p<0.05). Other temporal and spatial measurements were not statistically significant in the comparisons among the age groups. The vertical distance of the cervical vertebra was related to vertical excursion of the hyoid bone (p=0.002), and the horizontal distance from the chin to the cervical vertebra was related to the horizontal excursion of the hyoid bone (p=0.003). CONCLUSION: This paper describes a method for assessing temporal and spatial relationships of hyolaryngeal movement, and the passage of a bolus during swallowing. The two-dimensional kinematic swallowing motion analyses that were developed provided useful data that changed with age.


Assuntos
Envelhecimento/fisiologia , Transtornos de Deglutição/diagnóstico , Deglutição/fisiologia , Epiglote/fisiologia , Osso Hioide/fisiologia , Adulto , Idoso , Fenômenos Biomecânicos , Transtornos de Deglutição/fisiopatologia , Epiglote/fisiopatologia , Feminino , Humanos , Osso Hioide/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fotofluorografia , Valores de Referência , República da Coreia
7.
Arch Phys Med Rehabil ; 90(10): 1766-71, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19801069

RESUMO

UNLABELLED: Kang BS, Shin HI, Bang MS. Effect of repetitive transcranial magnetic stimulation over the hand motor cortical area on central pain after spinal cord injury. OBJECTIVE: To evaluate the analgesic effect of repetitive transcranial magnetic stimulation (rTMS) applied on the hand motor cortical area in patients with spinal cord injury (SCI) who have chronic neuropathic pain at multiple sites in the body, including the lower limbs, trunk, and pelvis. DESIGN: Blinded, randomized crossover study. SETTING: University hospital outpatient setting. PARTICIPANTS: Patients (N=13) with motor complete or incomplete SCI and chronic central pain (11 completed the study). INTERVENTIONS: rTMS was applied on the hand motor cortical area using a figure-of-eight coil. One thousand stimuli were applied daily on 5 consecutive days. Real and sham rTMS were separated by 12 weeks. MAIN OUTCOME MEASURES: Numeric rating scale (NRS) for average and worst pain and the Brief Pain Inventory (BPI). RESULTS: At 1 week after the end of the rTMS period, the average NRS scores changed from 6.45+/-2.25 to 5.45+/-1.81 with real stimulation and from 6.18+/-1.83 to 5.91+/-2.07 with sham stimulation, and did not differ between treatments. The interference items of the BPI also did not differ between the real and sham rTMS. The effect of time on the NRS score for worst pain was significant with real stimulation but not with sham stimulation. CONCLUSIONS: The therapeutic efficacy of rTMS was not demonstrated when rTMS was applied to the hand motor cortical area in patients with chronic neuropathic pain at multiple sites in the body, including the lower limbs, trunk, and pelvis. However, the results for worst pain reduction suggest that further studies are required in which rTMS is applied with a more intensive stimulation protocol.


Assuntos
Mãos/fisiopatologia , Córtex Motor/fisiopatologia , Manejo da Dor , Traumatismos da Medula Espinal/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Doença Crônica , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/fisiopatologia , Medição da Dor
8.
PM R ; 8(8): 808-12, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26902864

RESUMO

Ultrasound-guided percutaneous barbotage is an effective treatment for rotator cuff calcific tendinopathy, providing rapid and substantial pain relief. We present the case of a 49-year-old woman with aggravated pain early after ultrasound-guided barbotage of a large calcific deposit in the supraspinatus tendon. Subsequent examination revealed a thick calcification spreading along the subacromial-subdeltoid bursa space, suggesting acute calcific bursitis complicated by barbotage. Additional barbotage alleviated her pain completely. Therefore, a high index of suspicion for acute calcific bursitis is required in patients with unresolved or aggravated pain after barbotage. Repeated barbotage could be effective for this condition.


Assuntos
Bursite , Calcinose , Feminino , Humanos , Pessoa de Meia-Idade , Manguito Rotador , Tendinopatia , Ultrassonografia de Intervenção
9.
Laryngoscope ; 126(8): E286-91, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26650914

RESUMO

OBJECTIVES/HYPOTHESIS: To compare changes in hearing in patients with SLC26A4 during early and late childhood. STUDY DESIGN: Retrospective chart review. METHODS: A total of 102 patients with biallelic SLC26A4 mutations visited the tertiary referral otolaryngology department between March 2005 and February 2015. Newborn hearing screening tests had been performed on 22 of these patients. We analyzed 26 patients who underwent hearing tests more than twice using the same method (auditory brainstem response/auditory steady state response/play audiometry) before and after 3 years of age. We analyzed changes in hearing levels according to age. RESULTS: Among 22 patients with SLC26A4 mutations who underwent newborn hearing screening tests, seven (31.8%) passed the newborn hearing screening test in both ears, and six (27.3%) passed in one ear. Among 16 patients with SLC26A4 mutations who underwent hearing tests more than twice before age 3 years, the hearing levels of 14 (87.5%) deteriorated rapidly during this time. Among 16 patients with SLC26A4 mutations who underwent hearing tests more than twice after the age of 3 years, two (12.5%) patients' hearing levels deteriorated; the hearing levels of most of the patients were relatively stable. CONCLUSIONS: These data suggest that many patients with SLC26A4 mutations have significant residual hearing at birth, and that the hearing deterioration in these patients occurs before 3 years of age. After age 3 years, the residual hearing was relatively stable and did not tend to deteriorate. Therefore, in patients with a pendrin mutation, early intervention to preserve residual hearing should be a clinical focus. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:E286-E291, 2016.


Assuntos
Perda Auditiva/genética , Perda Auditiva/fisiopatologia , Proteínas de Membrana Transportadoras/genética , Mutação , Fatores Etários , Pré-Escolar , Feminino , Perda Auditiva/diagnóstico , Testes Auditivos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Transportadores de Sulfato
10.
Korean J Audiol ; 18(2): 69-75, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25279228

RESUMO

BACKGROUND AND OBJECTIVES: High-dose systemic steroid therapy is the mainstay treatment for sudden sensorineural hearing loss (SSNHL). Recovery rates from SSNHL range are about 47-63% and are influenced by various prognostic factors. To evaluate the prognostic value of specific clinical parameters, we reviewed 289 cases by clinical and statistical analysis. SUBJECTS AND METHODS: This study included 289 patients with SSNHL who visited the Department of Otolaryngology at Soonchunhyang University Hospital from January 2005 to December 2012. The cases were reviewed retrospectively based on clinical charts. Hearing improvement was evaluated in relation to pure-tone audiogram results, duration between SSNHL onset and time of initial treatment, seasonal incidence, dizziness, patient age, degree of hearing loss, patterns of initial pure-tone audiogram and presence of underlying disease. RESULTS: Hearing improvement was observed in 196 of 289 (67.8%) patients; such improvement began within 7 days in most patients, followed by rapid hearing recovery. Cases that failed to show improvement within 14 days were unlikely to achieve hearing recovery. The more severe the hearing loss during the early stage, the lower the hearing recovery rates. Patients aged less than 60 years appear to have better prognosis of hearing improvement compared to those who are over 60 years. CONCLUSIONS: Important prognostic factors for recovery in patients with SSNHL include the time of initiating treatment after symptom onset, the degree of early-stage hearing loss, and the age of the affected patient.

11.
Am J Phys Med Rehabil ; 86(11): 901-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17873826

RESUMO

OBJECTIVE: To assess the additive effect of adjuvant electrical stimulation on botulinum toxin A injection in children with spastic diplegic cerebral palsy. DESIGN: Eighteen children with dynamic foot equinus deformity were treated with botulinum toxin A injection into the calf muscles. Seven children were assigned to a treatment group who received botulinum toxin A and adjuvant electrical stimulation, and 11 children were assigned to a control group with botulinum toxin injection only. Before botulinum injection, and at 2 wks and 3 mos after injection, the Physician Rating Scale, passive ranges of ankle and knee motion, and the modified Ashworth scale were measured. RESULTS: A significant increase in passive range of ankle motion was observed at 2 wks after injection in the treatment group and at 3 mos after injection in both groups. Both groups showed significant improvements by the modified Ashworth scale at 2 wks after injection. Subscales of the Physician Rating Scale (equinus foot, crouched gait) and total Physician Rating Scale scores were significantly improved in the treatment group at 3 mos after injection, but this was not observed in the control group. CONCLUSIONS: Adjuvant electrical stimulation for a short period after botulinum toxin A injection was found to benefit early improvement of range of motion and maintenance of gait improvement in children with spastic diplegia cerebral palsy showing dynamic equinus.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/reabilitação , Terapia por Estimulação Elétrica , Marcha , Fármacos Neuromusculares/uso terapêutico , Toxinas Botulínicas Tipo A/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Injeções Intramusculares , Masculino , Músculo Esquelético , Fármacos Neuromusculares/administração & dosagem , Amplitude de Movimento Articular , Resultado do Tratamento
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