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1.
HardwareX ; 16: e00491, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38034102

RESUMO

Aerosol particles with rare specific properties act as nuclei for ice formation. The presence of ice nucleating particles in the atmosphere leads to heterogeneous freezing at warm temperatures and thus these particles play an important role in modulating microphysical properties of clouds. This work presents an ice nucleation cold stage instrument for measuring the concentration of ice nucleating particles in liquids. The cost is âˆ¼ $10 k including an external chiller. Using a lower cost heat sink reduces the cost to âˆ¼ $6 k. The instrument is suitable for studying ambient ice nucleating particle concentrations and laboratory-based process-level studies of ice nucleation. The design plans allow individuals to self-manufacture the cold-stage using 3D printing, off-the-shelf parts, and a handful of standard tools. Software to operate the instrument and analyze the data is also provided. The design is intended to be simple enough that a graduate student can build it as part of a course or thesis project. Costs are kept to a minimum to facilitate use in classroom demonstrations and laboratory classes.

2.
JSES Int ; 6(6): 999-1004, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36353419

RESUMO

Background: Arthroscopic distal clavicle resection (DCR) can be offered to patients with persistent acromioclavicular (AC) joint pain who do not benefit from conservative treatment. The aim of this study was to evaluate the outcome of combined arthroscopic DCR and concomitant arthroscopic subacromial decompression in a large consecutive and prospective cohort using patient-reported outcomes. Methods: Consecutive patients were identified from our online database and included based on their primary treatment code. All patients had a diagnosis of shoulder impingement syndrome and persistent AC joint pain resistant to at least six months of conservative treatment. The outcomes from the combined intervention were evaluated by patients through the Oxford Shoulder Score (OSS) questionnaire and EuroQol 5-Dimension 3-Level questionnaire, including a EuroQol visual analog scale score collected preoperatively and at a 2-year follow-up. Patient-reported satisfaction with the procedure was reported at the follow-up. Subgroups were formed to further evaluate outcome based on preoperative OSS (low, moderate, high) and age. Results: 131 patients (75%) were available for analysis at the 2-year follow-up. Sixty seven patients (51%) were female and the mean age was 51 years (range 19-82). A mean OSS change of 12.1 (95% confidence interval, 10.3-14.0; P < .001) was observed within the entire study group. In both the low and moderate preoperative-OSS (pre-OSS) groups, a mean change of 14 was found with no difference between groups (P = .971). A mean change of 7 was found in the high pre-OSS group, which differed from both the moderate (P < .001) and low (P = .036) pre-OSS groups. A significant change in EuroQol 5-Dimension and EuroQol visual analog scale was observed within all the pre-OSS groups, and 107 patients (82%) replied that they were satisfied or very satisfied with their outcome of surgery at the follow-up. Conclusions: Patients who suffer from persistent AC joint pain largely benefit from arthroscopic DCR with arthroscopic subacromial decompression through relief of symptoms and improved quality of life, including those with a high self-reported and preoperative level of shoulder function.

3.
Global Spine J ; 12(7): 1611-1623, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34927468

RESUMO

STUDY DESIGN: Systematic Review. OBJECTIVE: To evaluate the efficacy of available treatment options for patients with persistent coccydynia through a systematic review. METHODS: Original peer-reviewed publications on treatment for coccydynia were identified using Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines by performing a literature search of relevant databases, from their inception to January 17, 2020, combined with other sources. Data on extracted treatment outcome was pooled based on treatment categories to allow for meta-analysis. All outcomes relevant to the treatment efficacy of coccydynia were extracted. No single measure of outcome was consistently present among the included studies. Numeric Rating Scale, (NRS, 0-10) for pain was used as the primary outcome measure. Studies with treatment outcome on adult patients with chronic primary coccydynia were considered eligible. RESULTS: A total of 1980 patients across 64 studies were identified: five randomized controlled trials, one experimental study, one quasi-experimental study, 11 prospective observational studies, 45 retrospective studies and unpublished data from the DaneSpine registry. The greatest improvement in pain was achieved by patients who underwent radiofrequency therapy (RFT, mean Visual Analog Scale (VAS) decreased by 5.11 cm). A similar mean improvement was achieved from Extracorporeal Shockwave Therapy (ESWT, 5.06), Coccygectomy (4.86) and Injection (4.22). Although improved, the mean change was less for those who received Ganglion block (2.98), Stretching/Manipulation (2.19) and Conservative/Usual Care (1.69). CONCLUSION: This study highlights the progressive nature of treatment for coccydynia, starting with noninvasive methods before considering coccygectomy. Non-surgical management provides pain relief for many patients. Coccygectomy is by far the most thoroughly investigated treatment option and may be beneficial for refractory cases. Future randomized controlled trials should be conducted with an aim to compare the efficacy of interventional therapies amongst each other and to coccygectomy.

4.
Bone Joint J ; 103-B(3): 542-546, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641429

RESUMO

AIMS: The aim of this study was to investigate the efficacy of coccygectomy in patients with persistent coccydynia and coccygeal instability. METHODS: The Danish National Spine Registry, DaneSpine, was used to identify 134 consecutive patients who underwent surgery, performed by a single surgeon between 2011 and 2019. Routine demographic data, surgical variables, and patient-reported outcomes, including a visual analogue scale (VAS) (0 to 100) for pain, Oswestry Disability Index (ODI), EuroQol five-dimension questionnaire (EQ-5D), and the Physical Component Score (PCS) and Mental Component Score (MCS) of the 36-Item Short-Form Health Survey questionnaire (SF-36) were collected at baseline and one-year postoperatively. RESULTS: A total of 112 (84%) patients with a minimum follow-up of one year had data available for analysis. Their mean age was 41.9 years, and 15 (13%) were males. At 12 months postoperatively, there were statistically significant improvements (p < 0.001) from baseline for the mean VAS for pain (70.99 to 35.34), EQ-5D (0.52 to 0.75), ODI (31.84 to 18.00), and SF-36 PCS (38.17 to 44.74). A total of 78 patients (70%) were satisfied with the outcome of treatment. CONCLUSION: Patients with persistent coccydynia and coccygeal instability resistant to nonoperative treatment may benefit from coccygectomy. Cite this article: Bone Joint J 2021;103-B(3):542-546.


Assuntos
Cóccix/fisiopatologia , Cóccix/cirurgia , Dor Lombar/fisiopatologia , Dor Lombar/cirurgia , Adolescente , Adulto , Idoso , Dinamarca , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Medição da Dor , Sistema de Registros , Inquéritos e Questionários
5.
AIDS ; 33(7): 1143-1153, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30845069

RESUMO

BACKGROUND: HIV-2 may slow progression of a subsequently acquired HIV-1 infection through cross-neutralizing antibodies and polyfunctional CD8 T cells. We hypothesized that HIV-1/2 dually infected patients compared with HIV-1-infected patients had more preserved immune maturation subsets and less immune activation of T and B cells. METHODS: ART-naive patients with HIV-1 (n = 83) or HIV-1/2 dual (n = 27) infections were included in this cross-sectional study at an HIV clinic in Guinea-Bissau. Peripheral blood mononuclear cells (PBMCs) were analyzed by flow cytometry according to T-cell maturation and activation, regulatory T-cell fraction, and B-cell maturation and activation. RESULTS: HIV-1/2 dually infected patients had lower levels of HIV-1 RNA compared with patients with HIV-1 infection, but the levels of total HIV RNA (HIV-1 and HIV-2) were similar in the two patient groups. T-cell maturation, and proportions of regulatory T cells (FoxP3+) were also similar in the two groups. HIV-1/2 dually infected patients had higher proportions of CD4 and CD8 T cells positive for the activation marker CD38, but there was no difference in other T-cell activation markers (CD28, CTLA-4, PD-1). HIV-1/2 dually infected patients also had higher proportions of IgM-only B cells and plasmablasts. CONCLUSION: HIV-1/2 was not associated with less immune perturbations than for HIV-1 infection.


Assuntos
Linfócitos B/imunologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , HIV-2/isolamento & purificação , RNA Viral/sangue , Subpopulações de Linfócitos T/imunologia , Adulto , Estudos Transversais , Feminino , Citometria de Fluxo , Guiné-Bissau , Infecções por HIV/imunologia , Humanos , Imunofenotipagem , Leucócitos Mononucleares/imunologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Carga Viral
6.
Biotechnol Biofuels ; 11: 85, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29619081

RESUMO

BACKGROUND: Lignin is known to hinder efficient enzymatic conversion of lignocellulose in biorefining processes. In particular, nonproductive adsorption of cellulases onto lignin is considered a key mechanism to explain how lignin retards enzymatic cellulose conversion in extended reactions. RESULTS: Lignin-rich residues (LRRs) were prepared via extensive enzymatic cellulose degradation of corn stover (Zea mays subsp. mays L.), Miscanthus × giganteus stalks (MS) and wheat straw (Triticum aestivum L.) (WS) samples that each had been hydrothermally pretreated at three severity factors (log R0) of 3.65, 3.83 and 3.97. The LRRs had different residual carbohydrate levels-the highest in MS; the lowest in WS. The residual carbohydrate was not traceable at the surface of the LRRs particles by ATR-FTIR analysis. The chemical properties of the lignin in the LRRs varied across the three types of biomass, but monolignols composition was not affected by the severity factor. When pure cellulose was added to a mixture of LRRs and a commercial cellulolytic enzyme preparation, the rate and extent of glucose release were unaffected by the presence of LRRs regardless of biomass type and severity factor, despite adsorption of the enzymes to the LRRs. Since the surface of the LRRs particles were covered by lignin, the data suggest that the retardation of enzymatic cellulose degradation during extended reaction on lignocellulosic substrates is due to physical blockage of the access of enzymes to the cellulose caused by the gradual accumulation of lignin at the surface of the biomass particles rather than by nonproductive enzyme adsorption. CONCLUSIONS: The study suggests that lignin from hydrothermally pretreated grass biomass retards enzymatic cellulose degradation by acting as a physical barrier blocking the access of enzymes to cellulose rather than by inducing retardation through nonproductive adsorption of enzymes.

7.
Bioresour Technol ; 192: 826-30, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26051525

RESUMO

This work provides a comprehensive characterization of the gas phase from hydrothermal liquefaction of Dried Distillers Grains with Solubles (DDGS) collected during a 24-h continuous experiment. The gas consisted mainly of CO2, CO, H2, CH4 and C2H6 accounting for 96 v/v% while further analysis by gas chromatography coupled to mass spectrometry (GC-MS) showed additionally 62 compounds of which 54 were tentatively identified. These products included methanethiol, dimethyl sulfide, various olefins and several aromatic compounds. The composition provided clear indication of the steady state of the system. Apart from CO2, olefins were the most abundant compound class and could provide a source of revenue.


Assuntos
Gases/síntese química , Calefação/métodos , Compostos Orgânicos/síntese química , Água/química , Grãos Integrais/química , Dessecação , Gases/análise , Compostos Orgânicos/análise , Transição de Fase , Solubilidade , Soluções/síntese química
8.
Chem Commun (Camb) ; 50(84): 12612-4, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25032752

RESUMO

The selectivity of photocatalytic phenol production from the direct oxidation of benzene can be enhanced by fine adjustment of the morphology and composition of Au-Pd metal nanoparticles supported on titanium dioxide thereby suppressing the decomposition of benzene and evolution of phenolic compounds.


Assuntos
Ligas/química , Benzeno/química , Nanopartículas Metálicas/química , Fenol/síntese química , Titânio/química , Catálise , Ouro/química , Radical Hidroxila/química , Oxirredução , Paládio/química , Fenol/química , Raios Ultravioleta
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