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1.
Anal Sci ; 40(3): 413-427, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38170424

RESUMO

The plant Saussurea Simpsoniana, which has been used in traditional medicine for its biocompatibility and abundant nutrients, offers a wide range of remedies. Local communities effectively utilize medicines derived from the plant's roots to treat various ailments such as bronchitis, rheumatic pain, and abdominal and nervous disorders. In this study, we present an elemental analysis of the chemical composition (wt%) of this medicinal plant using the laser-induced breakdown spectroscopy (LIBS) technique. In the air atmosphere, an Nd:YAG (Q-switched) laser operating at a wavelength of 532 nm is utilized to create plasma on the sample's surface. This laser has a maximum pulse energy of approximately 400 mJ and a pulse duration of 5 ns. A set of six miniature spectrometers, covering the wavelength range of 220-970 nm, was utilized to capture and record the optical emissions emitted by the plasma. The qualitative analysis of LIBS revealed the presence of 13 major and minor elements, including Al, Ba, C, Ca, Fe, H, K, Li, Mg, Na, Si, Sr, and Ti. Quantitative analysis was performed using calibration-free laser-induced breakdown spectroscopy (CF-LIBS), ensuring local thermodynamical equilibrium (LTE) and optically thin plasma condition by considering plasma excitation temperature and electron number density. In addition, a comparison was made between the results obtained from CF-LIBS and those acquired through energy-dispersive X-ray spectroscopy (EDX) analysis.


Assuntos
Plantas Medicinais , Saussurea , Lasers , Espectrometria por Raios X , Sementes
2.
J Fluoresc ; 32(6): 1977-1989, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35789318

RESUMO

In these studies, Fluorescence spectroscopy has been utilized for the characterization of pure and commercially available corn oil. The best excitation wavelength of 380 nm has been investigated, where maximum spectral information can be assessed. The emission spectra from pure and commercial corn oil samples disclosed that pure corn oil contained oleic acid, beta-carotenes, chlorophylls, isomers of vitamin E and traces of oxidized products which exhibit fluorescence at 406, 525, 675, 440 and 435/475 nm respectively. Whereas, commercial corn oils lack these valuable ingredients and only contain fats along with their primary and secondary oxidized products that emit a broad emission band centred at 440 nm. The study has also depicted that Fluorescence spectroscopy can even be used to select best quality corn oil among pure corn oil samples with different varieties and seed origins. In addition, the effect of temperature on the composition of pure and commercial corn oil samples have also been investigated by heating them at 100, 120,140, 160, 180 and 200 °C each sample for 30 min. This was done because corn oil is being used for cooking where it is generally heated up to 120 °C and for deep frying up to 180 °C. On heating, in pure corn oil, deterioration of Vitamin-E and beta-carotenes occurred with an increase in the oxidation products, whereas, in commercial oil samples, only the concentration of oxidation products increased. However, it was found that up to 140 °C, pure corn oil can be used safely for cooking purpose where it does not lose much of its valuable ingredients while in commercial corn oils, fat composition does not alter much up to 180 °C and after that oxidized products start to increase rapidly.


Assuntos
Óleo de Milho , Ácido Oleico , Óleo de Milho/química , Espectrometria de Fluorescência , Óleos de Plantas/química , Temperatura Alta , Vitamina E , beta Caroteno , Vitaminas
3.
J Arthroplasty ; 37(2): 238-242, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34699914

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) deficiency is commonly considered a contraindication for unicompartmental knee arthroplasty (UKA). The purpose of this study is to compare the outcomes of UKA after prior ACL reconstruction (rACL cohort) to UKA with an intact native ACL (nACL cohort). METHODS: Forty-five patients from 3 institutions who underwent medial UKA after prior rACL were matched by age, gender, preoperative function scores, and body mass index to 90 patients who underwent UKA with an intact nACL. Primary outcomes were Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Oxford Knee Scores, Knee Society Functional Scores, and Kellgren-Lawrence scores in the unresurfaced, lateral tibiofemoral compartment. Secondary outcomes were postoperative complications and the need for revision to TKA. RESULTS: At a mean of 3.6 years, all PROMs improved significantly with no differences identified between groups. The incidence of revision TKA was similar between cohorts (P = 1.00); however, the mean time to revision for progressive osteoarthritis was 4.0 years in the nACL group and 2.2 years in the rACL group. Twenty percent of rACL patients had a postoperative complication compared to 8% in the nACL group. Despite presenting with a similar degree of lateral arthritis, a greater percentage of patients developed Kellgren-Lawrence scores of ≥3 in the rACL cohort (9%) than in the nACL cohort (0%). CONCLUSION: A previously reconstructed ACL does not appear to compromise the short-term functional outcomes of UKA; however, there is a higher rate of minor complications and progression of lateral compartment arthritis, which should be considered with patients in the shared decision process.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Artroplastia do Joelho , Osteoartrite do Joelho , Ligamento Cruzado Anterior/cirurgia , Artroplastia do Joelho/efeitos adversos , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Resultado do Tratamento
4.
J Orthop Trauma ; 35(12): e475-e480, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34797783

RESUMO

OBJECTIVES: (1) To evaluate adequacy and reproducibility of the gravity and manual stress imaging in the diagnosis of unstable ankle fractures and (2) to evaluate the diagnostic utility of lateral talar displacement ratio (LTDR) derived in relation to the talar body width on ankle stress imaging. DESIGN: Retrospective cohort study. SETTING: Level 1 Trauma Center. PATIENTS: One hundred seventy consecutive patients who presented with supination-external rotation 2 ankle fractures (OTA/AO 44-B2.1) requiring dynamic stress testing. INTERVENTION: Dynamic stress imaging to determine ankle stability. MAIN OUTCOME MEASURE: Ankle instability and subsequent need for surgical fixation as determined by dynamic stress imaging. RESULTS: No statistical significant difference was found between the adequacy of gravity stress radiographs and manual stress images in regards to surgical decision-making (P = 0.595). Using manual and gravity stress images, receiver operating characteristic curves were generated for medial clear space (MCS) (area under the curve = 0.793, 0.901) and LTDR (0.849, 0.850), corresponding to thresholds of 10.5% and 10.2% for manual and gravity, respectively. Seventy-three of 105 patients (69.5%) with MCS > 5 mm and 62 of 75 patients (82.7%) with LTDR > 10% were offered surgical intervention. Sixty-two of the 77 patients (80.5%) offered surgery had both MCS > 5 mm and LTDR > 10%. CONCLUSION: This study shows that manual stress radiographs are just as effective as gravity stress radiographs in making an assessment of ankle fracture stability as there was no difference in diagnostic value between gravity and manual stress imaging in regards to surgical decision-making. Use of additional radiographic measurements such as the LTDR can provide additional information in determining stability when MCS is within a clinical gray area. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Fraturas do Tornozelo , Tornozelo , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Supinação
5.
Appl Opt ; 59(14): 4240-4246, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400397

RESUMO

We have determined the absolute transition probabilities of 27 emission lines of neutral argon originating from the 3p54p→3p54s transition array in the wavelength region from 650 to 1100 nm using an argon-filled hollow cathode discharge lamp. The absolute transition probabilities have been deduced using the lifetimes of the upper levels and the measured branching fractions. Atomic oscillator strengths and relative line strengths for all the transitions have been computed using calculated transition probabilities. The experimentally determined transition probabilities are found to be in good agreement with that calculated in the intermediate coupling (IC) scheme. The comparison of experimentally determined transition probabilities with reported theoretical transition probabilities confirms that the IC scheme for the lower as well as for the upper levels seems to be a useful scheme for the level designation for the 3p54p to 3p54s configuration-based levels in argon. Furthermore, the measured relative line strengths are used to validate the J-file sum rule for the 3p54p→3p54s transition array of argon. The reported transition probabilities, oscillator strengths, and relative line strengths are compared with the published data, showing good agreement.

6.
Appl Opt ; 59(8): 2559-2568, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32225797

RESUMO

We studied laser ablation and plasma property evolution for a nickel (Ni) doped tin (Sn) oxide nanostructures target using laser-induced breakdown spectroscopy (LIBS). The transition metal Ni doped tin oxide nanostructures were synthesized by co-precipitation and hydrothermal methodologies. The size of prepared nanoparticles was verified by X-ray diffraction and transmission electron microscopy techniques. A frequency-doubled pulsed Nd:YAG laser with a wavelength of 532 nm was used to produce ablated plasma nanostructures. Ablation of doped and undoped nanostructures revealed salient-enhanced spectral emissions compared with their bulky counterparts. The emission lines of the constituent elements of doped material were used to find plasma parameters. The plasma temperature was estimated from a Boltzmann plot, and the electron number density was determined from the Saha-Boltzmann equation. The self-absorption effect has been observed in tiny plasma of nanostructures. The affected profiles of spectral lines of Ni and Sn nanoparticles due to self-absorption in LIBS spectra were corrected by the internal reference self-absorption correction (IRSAC) methodology. After correction of emitted line intensities by IRSAC, the electron number density (END) conservation approach was applied for quantitative analysis of doped nanostructures. In the END conservation approach, quantitative analysis of samples was carried out using electron number densities. Quantitative results derived from the END conservation approach at high and low concentrations exhibited good correlation when these were compared and validated with results from a conventional calibration free approach and the standard recognized energy dispersive X-ray technique.

7.
Appl Spectrosc ; 73(1): 30-39, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29972315

RESUMO

The qualitative and quantitative analysis of doped nanomaterial containing iron (Fe) and tin (Sn) nanoparticles was investigated using laser-induced breakdown spectroscopy (LIBS). Doped nanoparticles were prepared via co-precipitation and hydrothermal processes. The emission spectra of ablated plasma of doped material revealed the existence of different species in the doped nanomaterial. Simple calibration-free LIBS (CF-LIBS) and internal reference self-absorption correction (IRSAC) CF-LIBS approaches were applied to emission spectra of nanomaterial for quantitative analysis. For both approaches, different spectroscopic parameters such as plasma temperature and electron number density were also determined. Plasma temperature was estimated using a Boltzmann plot and Saha-Boltzmann plot while electron number density was estimated by Stark broadening methods and Saha-Boltzmann equations. Results of both calibration-free approaches were compared with a weight percentage method and other recognized techniques such as laser ablation time of flight (LA-TOF) spectroscopy and energy dispersive X-ray (EDX). We concluded that our results provide good agreement with experimental data obtained using LA-TOF spectroscopy and a small deviation from data obtained using the EDX technique. The current work confirms LIBS as a valid analytical approach for quantitative analysis of nanomaterials.

8.
Case Rep Orthop ; 2015: 163812, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26064739

RESUMO

Background. The standard use of vaccinations against pathogens has resulted in a decreased incidence of musculoskeletal infections caused by these previously common bacterial pathogens. Consequently, the incidence of infections caused by atypical bacteria is rising. This report presents a case of septic arthritis caused by non-type b H. influenzae in a pediatric patient. Methods. We report a case of an infant with polyarticular septic arthritis caused by H. influenzae serotype f. A literature review was conducted with the inclusion criteria of case reports and studies published between 2004 and 2013 addressing musculoskeletal H. influenzae infections. Results. An 8-month-old female presented with pain and swelling in her right ankle and left elbow. The patient was diagnosed with septic arthritis and underwent incision and drainage. Wound and blood cultures were positive for Haemophilus influenzae serotype f. In addition to treatment with IV antibiotics, the patient underwent immunocompetency studies, which were normal. Subsequent follow-up revealed eradication of the infection. Conclusions. Haemophilus influenzae non-type b may cause serious invasive infections such as sepsis or septic arthritis in children with or without predisposing factors such as immunodeficiency or asplenia. Optimal treatment includes surgical management, culture driven IV antibiotics, and an immunologic workup.

9.
Case Rep Orthop ; 2014: 285675, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25548700

RESUMO

Background. A discoid meniscus is a thickened variant of the normal C-shaped meniscus prone to injury. Discoid medial meniscal tears have rarely been reported within families and may suggest familial or developmental origins. Methods. We report the cases of two Caucasian brothers with symptomatic discoid medial meniscus tears. A literature review was conducted addressing discoid medial meniscus and cases of familial meniscus tears. Case Presentation. Physically active brothers presented with progressively worsening knee pain. MRI revealed medial meniscus tears in both brothers. The family history of medial meniscus tears in their mother and the discoid medial meniscus injuries found on arthroscopy suggested evidence for familial discoid medial meniscus tears. Conclusions. Discoid medial meniscus tears within a family have not been previously reported. Two cases of families with discoid lateral meniscus tears have been reported. Discoid medial meniscus is rare relative to the discoid lateral meniscus and predisposes children to symptomatic tears.

10.
Obstet Gynecol Surv ; 69(3): 147-58, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25102346

RESUMO

In the present study, we review the indications, technical aspects, preliminary results, risks, and clinical implications of fetal endoscopic tracheal occlusion (FETO) for severe congenital diaphragmatic hernia (CDH) performed outside the United States and its potential future directions in this country and globally. Congenital diaphragmatic hernia occurs in approximately 1 in 2500 live births and results in high neonatal morbidity and mortality, largely associated with the severity of pulmonary hypoplasia and pulmonary arterial hypertension. With the advent of prenatal imaging, CDH can be diagnosed before birth, and in utero treatment is now available in some centers. The prognosis of CDH can be evaluated by assessing the fetal lung size, the degree of liver herniation, and the fetal pulmonary vasculature in isolated forms of CDH. These parameters help classify fetuses as having mild, moderate, severe, or extremely severe isolated CDH. Severe and extremely severe diaphragmatic hernias have poor outcomes and thus are candidates for innovative therapies such as FETO. Fetal endoscopic tracheal occlusion is usually performed between 26 and 30 weeks' gestation. In utero, an endoscope is passed through the fetal mouth and down to the carina; the balloon is deployed just above the carina. After the procedure, ultrasound surveillance every 2 weeks ensures the balloon's structural integrity and measures the fetal pulmonary response. At approximately 34 weeks' gestation, the balloon is deflated and removed. Fetal endoscopic tracheal occlusion is thought to improve outcomes by decreasing mortality and allowing more rapid neonatal stabilization. Ultimately, the goal of FETO is to minimize pulmonary hypoplasia and pulmonary arterial hypertension. Following delivery, neonates still require diaphragm repair.


Assuntos
Endoscopia/métodos , Doenças Fetais/cirurgia , Hérnias Diafragmáticas Congênitas/cirurgia , Anormalidades Múltiplas/prevenção & controle , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/epidemiologia , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/epidemiologia , Humanos , Hipertensão Pulmonar/prevenção & controle , Pulmão/anormalidades , Pneumopatias/prevenção & controle , Prognóstico , Índice de Gravidade de Doença , Ultrassonografia Pré-Natal
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