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1.
Opt Express ; 24(6): 6318-27, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27136823

RESUMO

Signal-to-noise ratio is a key factor in lensless imaging, particularly for low diffraction signal experiments in the single shot regime. We present our recent study of the noise impact on holography with extended references. Experimental data have been measured in single shot acquisition using an intense coherent soft X-ray high harmonic source. The impact of hardware and software noise under various detection conditions is discussed. A final comparison between single shot and multi-shot regimes is given.

2.
Microbiology (Reading) ; 161(Pt 1): 213-218, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25406450

RESUMO

Investigation of a series of nutrient-supplemented thixotropic gels at successive dilutions that impede the trajectories of a highly vigorous motile flagellated protist, Spironucleus vortens, provides insights into both its swimming characteristics and a means for its immobilization. The progress of movement of this organism through the solidified growth medium was monitored by the in situ reductive production of a formazan chromophore from a dissolved tetrazolium salt. The physical properties of the gels were measured using an Anton Paar rheometer. The test parameters and measurements included: angular frequency, complex viscosity, complex shear modulus, shear rate and rotational recovery. These rheological characteristics affected the forward velocity of the organism through the gels, during and after multiple resetting, information potentially useful for determination of the dynamic characteristics of flagellar movement and propulsion rates of the organism. Application to separation of single cells, individuals of distinct sizes or the differing species from mixed cultures of motile and non-motile organisms or less actively swimming species was evident. These applications can be used when isolating the parasite from the intestinal contents of its host or from faecal pellets.


Assuntos
Diplomonadida/fisiologia , Peixes/parasitologia , Animais , Meios de Cultura , Diplomonadida/ultraestrutura
3.
Opt Lett ; 40(13): 3205-8, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26125403

RESUMO

We demonstrate a method of using a Fourier holographic technique to utilize attosecond soft x-ray pulses to image nanometer-scale objects. A discrete frequency comb of laser-generated high-order harmonics, yielding a train of attosecond pulses, has been used to record spatially and spectrally resolved images. The individual wavelengths were also combined to form a single image, albeit with lower spatial resolution, demonstrating the applicability of the method to using isolated attosecond pulses with continuous bandwidths.

4.
Ann Med Surg (Lond) ; 85(7): 3339-3346, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37427156

RESUMO

High tibial osteotomy is a reliable procedure for the correction of knee varus deformity. An opening-wedge high tibial osteotomy (OW-HTO) is the most popular technique. The results of the bone defect after opening the wedge needed special treatment to ensure bone healing. This study aims to evaluate the use of bovine-derived hydroxyapatite graft for defect filling after OW-HTO. Methods: A retrospective study was performed on all patients who received OW-HTO at Prof. Dr R. Soeharso Orthopaedic Hospital from November 2019 to December 2022. A total of 21 patients (24 knees) were included in this study. Clinical dan radiological evaluation was performed on all patients preoperative and postoperatively. The mean of the follow-up period was 12.6 months with a minimum of 4 months follow-up. Results: Primary medial uni-compartment knee osteoarthritis was the most common diagnosis, with 17 of 24 cases (70.8%). Mechanical axis deviation was changed from 31 mm medial deviation (range: 8-52 mm) to 0.45 mm medial deviation (range: 13 - (-8) mm). The anatomic tibiofemoral angle was corrected from a preoperative mean of 4.7° of varus to a mean of 5.8° of valgus postoperatively. Bone defect height was mean 15.9 mm with a range of 10-23 mm. Bone defect width was mean 46.7 mm (range: 34-60 mm). Hydroxyapatite graft integration with the host bone was found in all patients during the final follow-up period. Conclusions: Bovine-derived hydroxyapatite graft is a safe and effective material for bone defect filling in OW-HTO procedures with a high bone union rate.

5.
Phys Rev Lett ; 108(13): 133401, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22540697

RESUMO

Explosions of large Xe clusters ( ~ 11,000) irradiated by femtosecond pulses of 850 eV x-ray photons focused to an intensity of up to 10(17) W/cm(2) from the Linac Coherent Light Source were investigated experimentally. Measurements of ion charge-state distributions and energy spectra exhibit strong evidence for the formation of a Xe nanoplasma in the intense x-ray pulse. This x-ray produced Xe nanoplasma is accompanied by a three-body recombination and hydrodynamic expansion. These experimental results appear to be consistent with a model in which a spherically exploding nanoplasma is formed inside the Xe cluster and where the plasma temperature is determined by photoionization heating.

6.
Phys Rev Lett ; 104(22): 225501, 2010 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-20867179

RESUMO

We reconstructed the 3D Fourier intensity distribution of monodisperse prolate nanoparticles using single-shot 2D coherent diffraction patterns collected at DESY's FLASH facility when a bright, coherent, ultrafast x-ray pulse intercepted individual particles of random, unmeasured orientations. This first experimental demonstration of cryptotomography extended the expansion-maximization-compression framework to accommodate unmeasured fluctuations in photon fluence and loss of data due to saturation or background scatter. This work is an important step towards realizing single-shot diffraction imaging of single biomolecules.


Assuntos
Análise de Fourier , Imageamento Tridimensional/métodos , Espalhamento de Radiação , Tomografia/métodos , Estudos de Viabilidade , Compostos Férricos/química , Nanopartículas/química
7.
Microsurgery ; 30(3): 230-2, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20073033

RESUMO

This report describes two incidental findings of aberrant branches of the radial digital nerves in the middle finger of a 52-year-old man who cut himself with a grinding machine, and in the index finger of a 45-year-old female who sustained a flexor sheath infection following a dog bite. In both patients, two equally sized radial digital nerves were found and both nerves originated from one common digital nerve.


Assuntos
Traumatismos dos Dedos/cirurgia , Dedos/inervação , Nervo Radial/anormalidades , Animais , Mordeduras e Picadas/cirurgia , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nervo Radial/cirurgia
8.
Opt Express ; 17(20): 18271-8, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19907618

RESUMO

We have focused a beam (BL3) of FLASH (Free-electron LASer in Hamburg: lambda = 13.5 nm, pulse length 15 fs, pulse energy 10-40 microJ, 5 Hz) using a fine polished off-axis parabola having a focal length of 270 mm and coated with a Mo/Si multilayer with an initial reflectivity of 67% at 13.5 nm. The OAP was mounted and aligned with a picomotor controlled six-axis gimbal. Beam imprints on poly(methyl methacrylate) - PMMA were used to measure focus and the focused beam was used to create isochoric heating of various slab targets. Results show the focal spot has a diameter of < or =1 microm. Observations were correlated with simulations of best focus to provide further relevant information.


Assuntos
Lasers , Lentes , Teste de Materiais/instrumentação , Teste de Materiais/métodos , Difração de Raios X/instrumentação , Difração de Raios X/métodos , Desenho Assistido por Computador , Elétrons , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Pharm Bioallied Sci ; 10(1): 43-47, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29657507

RESUMO

INTRODUCTION: Ultrahigh-molecular-weight polyethylene (UHMWPE) is a thermoplastic polymer useful in biomaterial applications, especially in orthopedic field. Yet, little is known concerning its initial effect on human bone marrow stem cells (hBMSCs) after implantation. MATERIALS AND METHODS: A cytotoxicity analysis was performed with a 3-(4,5-dimethylthiazol 2-yl)-2,5-diphenyltetrazolium assay after 24, 48, and 72h of incubation of hBMSC culture. Expression of interleukin-6 (IL-6) was measured using enzyme-linked immunosorbent assay. Cell viability was measured with Inhibitory concentration 50% (IC50) formula. RESULTS: All treatment groups showed a cell viability of >50% ranging from 78% to >100%. Lower expression of IL-6 of hBMSC compared to control group was found in 48h of incubation period. CONCLUSION: hBMSC showed high cell viability after initial contact with UHMWPE material. Modulation of IL-6 expression was present at the initial stage as a response to foreign material.

10.
J Clin Pathol ; 60(3): 295-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16731590

RESUMO

AIM: To identify and review cases of false negative needle core biopsy (NCB) in the preoperative investigation of radial scar/complex sclerosing lesion (RS/CSL) lesions - that is, benign NCB from RS/CSL which contained malignancy on excision. METHODS AND RESULTS: A total of 11 false negative NCB in RS/CSL lesions from 281 (3.9%) were identified (6 cases: B1, 2 cases: B2 and 3 cases: B3). In 6 of 11 cases a radial scar or stromal sclerosis was seen in NCB. Localisation biopsy showed duct carcinoma in situ in six cases, duct carcinoma in situ with invasive carcinoma in three and invasive carcinoma in two. In all 11 cases, needle tracks were identified as missing the malignant epithelium by a mean of 5 mm (median:4 mm; range:1-20 mm). In 9 of 11 cases, the malignancy was missed by <6 mm. CONCLUSIONS: Despite evidence of accurate targeting of lesions, the use of NCB instead of fine needle aspiration cytology has not eliminated the problem of false negative biopsy in RS/CSL, and excision is recommended.


Assuntos
Neoplasias da Mama/patologia , Biópsia por Agulha , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Reações Falso-Negativas , Feminino , Humanos , Mamografia , Programas de Rastreamento
11.
J Med Genet ; 40(9): 676-81, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12960213

RESUMO

BACKGROUND: The aetiology of atypical haemolytic uraemic syndrome (aHUS) is, in contrast to classical, Shiga-like toxin induced HUS in children, largely unknown. Deficiency of human complement factor H and familial occurrence led to identification of the factor H gene (FH1) as the susceptibility gene, but the frequency and relevance of FH1 mutations are unknown. METHODS: We established a German registry for aHUS and analysed in all patients and 100 controls the complete FH1 gene by single strand confirmational polymorphism and DNA sequencing. In addition, complement C3 and factor H serum levels were assayed. Demographic data at onset of aHUS and follow up were compared for the mutation positive and negative groups. RESULTS: Of 111 patients with aHUS (68 female, 43 male, mean age 33 years) 14% had FH1 germline mutations, including two of eight patients with familial aHUS. For each of these eight patients, both parents were tested, and we were able to trace the mutation for five cases. In the other three cases (one with the mutation 3749 C/T, one with 3200 T/C, and one with 3566+1 G/A), we could not detect the mutation in either parent, although paternity was proven by genetic fingerprinting, suggesting that these subjects have new mutations. C3 was decreased in five mutation carriers but also in two non-carriers, and factor H was decreased in none of the carriers, but elevated in six carriers and 15 non-carriers. Clinical parameters including associated medications and diseases, and outcome of aHUS and of post-aHUS kidney transplantation were similar in the mutation positive and negative groups. CONCLUSION: FH1 germline mutations occur with considerable frequency in patients with aHUS. Hypocomplementaemia is not regularly associated with a germline mutation, and factor H serum levels can even be elevated. Screening for FH1 mutations contributes to the classification of aHUS.


Assuntos
Fator H do Complemento/genética , Síndrome Hemolítico-Urêmica/genética , Adulto , Áustria , Complemento C3/metabolismo , Fator H do Complemento/metabolismo , DNA/química , DNA/genética , Análise Mutacional de DNA , Ensaio de Imunoadsorção Enzimática , Feminino , Alemanha , Síndrome Hemolítico-Urêmica/sangue , Síndrome Hemolítico-Urêmica/complicações , Humanos , Itália , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Transplante de Rim , Masculino , Mutação , Polimorfismo Conformacional de Fita Simples , Sistema de Registros/estatística & dados numéricos , Suíça
13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(1 Pt 2): 016403, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21405780

RESUMO

Studies of materials under extreme conditions have relevance to a broad area of research, including planetary physics, fusion research, materials science, and structural biology with x-ray lasers. We study such extreme conditions and experimentally probe the interaction between ultrashort soft x-ray pulses and solid targets (metals and their deuterides) at the FLASH free-electron laser where power densities exceeding 10(17) W/cm(2) were reached. Time-of-flight ion spectrometry and crater analysis were used to characterize the interaction. The results show the onset of saturation in the ablation process at power densities above 10(16) W/cm(2). This effect can be linked to a transiently induced x-ray transparency in the solid by the femtosecond x-ray pulse at high power densities. The measured kinetic energies of protons and deuterons ejected from the surface reach several keV and concur with predictions from plasma-expansion models. Simulations of the interactions were performed with a nonlocal thermodynamic equilibrium code with radiation transfer. These calculations return critical depths similar to the observed crater depths and capture the transient surface transparency at higher power densities.

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