Journal articles on the topic 'Zeisel Technique'

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1

Man, Xiao-Lei, Wei-Kang Peng, Jun Chen, and Xue-Li Liu. "Analysis of Molar Substitution of Hydroxybutyl Group by Zeisel Reaction in Starch Ethers." Molecules 26, no. 18 (September 11, 2021): 5509. http://dx.doi.org/10.3390/molecules26185509.

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A new etherified starch, δ-hydroxybutyl starch (δ-HBS), was prepared by utilising 4-chlorobutan-1-ol as the etherifying reagent. The method of Zeisel gas chromatography for the determination of the molar substitution was described. This technique offers a simple and rapid method for quantitative analysis with reproducible results. Meanwhile, the mechanism of the Zeisel reaction was also investigated.
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Souhoka, Fensia Analda, Harno Dwi Pranowo, and Tutik Dwi Wahyuningsih. "Synthesis of Methylcellulose Using Dimethyl Carbonate with Conventional and Green Methods." Key Engineering Materials 884 (May 2021): 379–86. http://dx.doi.org/10.4028/www.scientific.net/kem.884.379.

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Synthesis of methylcellulose (MC) using dimethyl carbonate (DMC) with conventional and green methods has been conducted. The cellulose used in this synthesis was obtained from sago waste, which contains 86.67% cellulose. All the methylation products were analyzed using IR and 1H-NMR spectrometers. The determination of cellulose content was done using TAPPI T-203 method, while the degree of substitution (DS) was based on the Zeisel Method. Conventional synthesis of MC was performed using Na2HPO4 (12:1), DMC and NaCl 5% (w/v) (volume ratio = 10:10) at 90 °C. The reaction time was varied (2 to 5 hours); the optimum condition was reached in 3 hours and gave the DS of 1.028. Green synthesis of MC was conducted by employing microwave and sonochemistry techniques. Synthesis MC with the microwave was carried out at the power of 400 W for 200 seconds and gave the DS of 1.036. Synthesis MC with sonochemistry (the variation time 1 to 3 hours) was conducted at the optimum time of 2 hours and gave the DS of 0.646. The DMC volume was also varied (17.5; 20; 22.5; 25; and 30 mL), where the volume ratio of 1:24 gave the highest DS of 1.177. The microwave technique is the best method for synthesis MC compared to conventional and sonochemistry techniques.
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3

Bock, Markus, Alexander Ulrich Brandt, Jan Dörr, Caspar F. Pfueller, Stephanie Ohlraun, Frauke Zipp, and Friedemann Paul. "Time domain and spectral domain optical coherence tomography in multiple sclerosis: a comparative cross-sectional study." Multiple Sclerosis Journal 16, no. 7 (March 29, 2010): 893–96. http://dx.doi.org/10.1177/1352458510365156.

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Conventional time domain optical coherence tomography has been established for the in vivo assessment of retinal axonal loss in multiple sclerosis. The innovative spectral domain imaging is superior to the conventional technique with respect to data acquisition speed, resolution and reproducibility. However, until now comparability of the two techniques has not been investigated in multiple sclerosis. In this study involving 55 multiple sclerosis patients, data obtained using both techniques (Stratus time domain optical coherence tomography and Cirrus spectral domain optical coherence tomography, Carl Zeiss Meditec) showed an excellent correlation (Pearson’s r = 0.926, p < 0.001). However, owing to considerable differences in absolute retinal nerve fibre layer measurements (mean ± standard deviation 8.1 µm ± 6.2, range -12 to 23 µm), results from the two devices are not interchangeable.
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4

Heard, Rhiannon, Clive R. Siviour, and Kalin Dragnevski. "Investigating Iron Alloy Phase Changes Using High Temperature In Situ SEM Techniques." Materials 15, no. 11 (May 31, 2022): 3921. http://dx.doi.org/10.3390/ma15113921.

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This research utilises a novel heat stage combined with a Zeiss scanning electron microscope to investigate phase changes in iron alloys at temperatures up to 800 ℃ using SE and EBSD imaging. Carbon steel samples with starting structures of ferrite/pearlite were transformed into austenite using the commercial heat treatment process whilst imaging within the SEM. This process facilitates capturing both grain and phase transformation in real time allowing better insight into the microstructural evolution and overall phase change kinetics of this heat treatment. The technique for imaging uses a combination of localised EBSD high temperature imaging combined with the development of high temperature thermal-etching SE imaging technique. The SE thermal etching technique, as verified by EBSD images, enables tracking of a statistically significant number of grains (>100) and identification of individual phases. As well as being applied to carbon steel as shown here, the technique is part of a larger study on high temperature in situ SEM techniques and could be applied to a variety of alloys to study complex phase transformations.
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5

Lee, Jae Hun, and Seoung Hyun An. "The Refractive Outcomes of Sutured and Sutureless Scleral Fixation (the Yamane Technique)." Journal of the Korean Ophthalmological Society 63, no. 10 (October 15, 2022): 841–48. http://dx.doi.org/10.3341/jkos.2022.63.10.841.

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Purpose: To evaluate the pre- and post-operative refractive powers of patients undergoing sutured and sutureless scleral fixation (the latter: the Yamane technique).Methods: Patients who had undergone sutured or sutureless scleral fixation to treat intraocular lens (IOL) dislocation or phacodonesis at Dong-A University Hospital from January 2017 to December 2021 were retrospectively investigated. The preoperatively predicted spherical equivalents (derived using the radii of corneal curvature) were measured via optical coherence topography and the axial lengths were determined using an IOL master ® (Zeiss, Carl Zeiss Meditec, Jena, Germany) device and A-scan biometry (AL-100; Tomey, Nagoya, Japan) ultrasound. The spherical equivalent was measured 1 month after surgery employing an automatic refractive keratometer. The extent of agreement between the predicted and actual spherical equivalents were compared between the sutured and sutureless scleral fixation groups.Results: The sutured scleral fixation group included 20 eyes and the sutureless group 12 eyes. The preoperatively predicted spherical equivalent of the sutured group was -0.158 ± 0.577 diopters (D) on A-scan (Tomey) ultrasound and -0.143 ± 0.617 D employing the IOL master ® (Carl Zeiss Meditec); both correlated poorly with the postoperatively measured spherical equivalent of -0.400 ± 0.923 D (p = 0.903, 0.563). However, the predicted spherical equivalent of the group undergoing sutureless fixation was -0.340 ± 0.368 D on A-scan ultrasound and -0.183 ± 0.251 D using the IOL master ® (Carl Zeiss Meditec); both correlated significantly with the postoperatively measured spherical equivalent of -0.313 ± 1.129 D (p = 0.038, 0.005).Conclusions: The preoperatively predicted refractive power correlated significantly with the postoperative refractive power after sutureless but not sutured scleral fixation. Sutureless fixation was safe and the postoperative refractive power was comparable to that of sutured fixation.
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6

Dudek, Marta. "Self-healing cement materials – microscopic techniques." Budownictwo i Architektura 19, no. 2 (June 30, 2020): 033–40. http://dx.doi.org/10.35784/bud-arch.1494.

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The article presents a general classification of intelligent materials with self-healing (self-repairing) properties, focusing on self-healing cementitious materials. The purpose of the paper is to describe the prospects of two of the most popular micro-observation techniques, i.e. with the use of an optical and scanning electron microscope. In addition, it describes the advantages of using a tensile stage mounted in the microscope chamber for testing self-healing materials. The advantages and disadvantages of these devices have been characterized, and the results of preliminary research have been provided. The tests include the optical microscopy and scanning electron microscopy observations of the microstructure of cracks before and after the process of healing. They were carried out using ZEISS Discovery V20 optical microscope and ZEISS EVO-MA 10 scanning electron microscope on mortar samples modified with macro capsules filled with polymer. In addition to observations, chemical analysis was performed with the use of an EDS detector. The microscopic observations and chemical analyses provide the basis for assessing the effectiveness of the self-healing process, showing that the crack has been healed. Moreover, the preliminary results of the tests of micro-mechanical properties, carried out with the use of a tensile stage, have been described. The problems of using this research technique are also listed. This study shows the usefulness of this kind of tests for microcapsules for self-healing materials.
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7

Richmond, R. E., M. A. Pereira, J. H. Carter, H. W. Carter, and R. E. Long. "Quantitative and qualitative immunohistochemical detection of myc and src oncogene proteins in normal, nodule, and neoplastic rat liver." Journal of Histochemistry & Cytochemistry 36, no. 2 (February 1988): 179–84. http://dx.doi.org/10.1177/36.2.3121722.

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This study examined the possibility of using an immunohistochemical technique to detect the expression of myc and src oncogene proteins (ops) in livers of male Sprague-Dawley rats after treatment with the carcinogen diethylnitrosamine (with or without phenobarbital promotion) or untreated. We found that the majority of nodules and tumors from these livers stained for myc and src ops, indicating that myc and src expression did occur in these structures. These results were expected, since myc and src expression has been previously observed by others using different techniques. However, in our study, myc and src op staining was also noted in normal liver areas from rats in any of the four treatment groups (DENA, DENA + PB, PB alone, or untreated). The staining pattern of normal liver was different for each oncogene probe but was consistent within the four groups. In most cases, oncogene expression of normal liver occurred at sites of abnormal (but non-neoplastic) hepatocytes. The method reported here used both a qualitative technique of op expression analysis and a quantitative method using a Zeiss computer-driven image analysis system.
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8

Larner, Sean P., Rick A. Fornelli, and Shane D. Griffith. "Consistent Technique Limits Suspension Laryngoscopy Complications." International Archives of Otorhinolaryngology 23, no. 03 (May 28, 2019): e305-e310. http://dx.doi.org/10.1055/s-0039-1684036.

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Introduction Suspension laryngoscopy (SL) is a commonly performed procedure among otolaryngologists. Several studies have shown that adverse effects occur regularly with SL. Objective To evaluate the postoperative complications of SL, and to determine if protecting the dentition and the oral mucosa and limiting suspension times decrease the overall incidence of oral cavity and pharyngeal complications of SL. Methods All of the cases of SL performed by 1 surgeon from November 2008 through September 2014 were retrospectively reviewed. A consistent technique for dental and mucosal protection was utilized, and suspension times were strictly limited to 30 consecutive minutes. The incidence of postoperative complications was calculated and analyzed with respect to gender, smoking status, dentition, laryngoscope type, and suspension system. Results A total of 213 consecutive SL cases were reviewed, including 174 patients (94 male, 80 female). The overall postoperative complication rate was of 3.8%. Four patients experienced tongue-related complications, two experienced oral mucosal alterations, one had a dental injury, and one experienced a minor facial burn. The complication incidence was greater with the Zeitels system (12.5%) compared with the Lewy suspension system (3.3%), although it was not significant (p = 0.4). Likewise, the association of complications with other patient factors was not statistically significant. Conclusion Only 8 out of 213 cases in the present series experienced complications, which is significantly less than the complication rates observed in other reports. Consistent and conscientious protection of the dentition and of the oral mucosa and limiting suspension times to 30 minutes are factors unique to our series that appear to reduce complications in endolaryngeal surgery.
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9

Migalkin, N. S., T. A. Stupina, A. V. Kaminsky, D. S. Mokhovikov, D. A. Shabalin, B. V. Kamshilov, and A. Yu Kirsanova. "FEATURES OF THE PATHOMORPHOLOGICAL DIAGNOSIS OF MICROCRYSTALLINE ARTHROPATHIES IN THE PRACTICE OF SURGICAL MATERIAL EXAMINATION." Rheumatology Science and Practice 58, no. 3 (June 24, 2020): 286–89. http://dx.doi.org/10.14412/1995-4484-2020-286-289.

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The development of microcrystalline arthritides is most frequently associated with the formation of monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals. Their identification is of crucial importance in recognizing these diseases. Objective: to determine the possibilities of histological techniques in identifying MSU and CPP crystals and to evaluate the effectiveness of the techniques. Subjects and methods. Twenty-four tissue blocks (fragments of the affected areas of the elbow joint, the interphalangeal joint of the index finger, and hip joint) from 7 patients were examined. Paraffin sections were stained with a 0.5% alcohol solution of eosin, as well as with hematoxylin and eosin. Tissue specimens were examined and digitized using an AxioScope.A1 stereo microscope with Zenblue software (Carl Zeiss MicroImaging GmbH, Germany). Results and discussion. When staining the tissue sections with hematoxylin and eosin, microcrystals were not visualized; the major portions of MSU crystals was dissolved during fixation and staining, whereas CPP crystals were masked with hematoxylin as focal basophilic aggregates. The staining technique with an alcohol solution of eosin and short formalin fixation (within 12 hours) made it possible to avoid dissolution of MSU crystals and to visualize both MSU and CPP crystals, and to determine their shape and color. Conclusion. Light microscopy of the tissue sections stained with an alcohol solution of eosin along with short formalin fixation is a reliable method to differentiate MSU and CPP crystals. In patients undergoing endoprosthetic replacement, the significance of this technique for the pathomorphological study of surgical material consists in assessing inflammatory activity and in eliminating a disease, such as microcrystalline arthropathy.
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10

Crozier, P. A. "Energy-filtered chemical mapping: Current applications to materials science." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 958–59. http://dx.doi.org/10.1017/s0424820100172528.

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Elemental mapping is a powerful technique for elucidating the distribution of elements on the nanometer scale in materials with complex morphologies. In electron microscopy, mapping is usually performed on a scanning transmission electron microscope (STEM) fitted with a field emission gun (FEG) using the techniques of energy-dispersive x-ray spectroscopy (EDX) or electron energy-loss spectroscopy (EELS). However, recent advances in spectrometer design and digital image recording have stimulated renewed interest in energy-filtered imaging and elemental mapping with a conventional transmission electron microscope. Here, some applications of energy-filtered chemical mapping in materials science are described.Experiments were conducted on a Zeiss 912 operating at 120 kV with a thermal source and equipped with an omega filter spectrometer. A variable width slit in the spectrometer image plane allows energy-filtered images to be formed on the microscope viewing screen. These images are digitally recorded using a Gatan 679 slow-scan CCD camera with 1024 pixels.
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11

Hall, Philip S., David A. Thornton, and Gary A. Foulds. "Application of spectroscopic techniques to the complexes formed by reaction of zeise's salt derivatives with carbon monoxide." Polyhedron 6, no. 1 (January 1987): 85–94. http://dx.doi.org/10.1016/s0277-5387(00)81242-5.

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12

Schmid, Ueli, Nicolas Bircher, and Harald Bugmann. "Naturnaher und multifunktionaler Waldbau in Zeiten des Klimawandels – eine Fallstudie." Schweizerische Zeitschrift fur Forstwesen 166, no. 5 (May 1, 2015): 314–24. http://dx.doi.org/10.3188/szf.2015.0314.

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“Close-to-nature” and multifunctional silviculture in times of climate change – a case study The available assessments of the impacts of the expected climate change on the dynamics of Swiss forests are prone to considerable uncertainties and are mostly of qualitative nature; recommendations on silvicultural measures are therefore typically quite generic. Using a quantitative method, we analyzed whether today's best-practice silviculture remains valid under changing climatic conditions. Based on a stratification of the data from the National Forest Inventory NFI3, 71 typical Swiss forest stands were identified. Thereof, we chose six illustrative examples and examined how timber production, protective function and tree diversity evolve under climate change, using the ForClim forest model. In cooperation with silviculture experts, we elaborated specific management schemes for the upcoming 100 to 150 years considering different silvicultural objectives. In order to reproduce these in detail, ForClim was extended, and thereby an important basis for plausible, practice-oriented modelling was laid. The results show a satisfying behaviour of the newly introduced management techniques “mountain plentering” and “Z-tree management”. In the latter, the modelling of the selection of Z-trees can potentially be improved. In the six stand types investigated here, no abrupt changes in forest dynamics became apparent under the considered climate change scenarios. The results indicate that today's silviculture may remain suitable in the coming decades.
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Nielsen, Torfinnur Rubek, Ulrik Koks Andreassen, Christopher Leigh Brown, Viggo Hulthin Balle, and Jens Thomsen. "Microsurgical technique in thyroid surgery – a 10-year experience." Journal of Laryngology & Otology 112, no. 6 (June 1998): 556–60. http://dx.doi.org/10.1017/s0022215100141076.

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AbstractObjectiveTo report the results of thyroid surgery in a University department of ENT – head and neck surgery, and to evaluate the benefits of the use of the surgical microscope in thyroid surgery.DesignA retrospective evaluation of the records of all patients who underwent thyroid surgery in the 10-year period 1987–1996.MethodsIn addition to standard surgical principles the Zeiss multi-discipline universal surgical microscope with a 250 mm ocular lens was used in all cases. Total thyroidectomy was performed in all malignant cases, while unilateral lobectomy plus isthmus resection was the standard procedure in benign cases.PatientsThere were 573 patients, aged 11–87 years, 444 females and 129 males. Four hundred and fifty-one had benign lesions, 122 malignant. Four hundred and eighty-nine had primary surgery, 84 underwent completion surgery or surgery for recurrent disease.ResultsPrimary thyroid gland surgery in benign/malignant disease resulted in permanent recurrent laryngeal nerve palsy in 0.6 per cent/3.5 per cent of the patients respectively, when calculated as nerves at risk (NAR). In benign recurrent or malignant completion surgery this complication rate was 4.5 per cent/2.9 per cent respectively.ConclusionThyroid surgery in our University ENT – Head and Neck Department with the use of the surgical microscope provides pleasing results, especially considering the diversity of surgeons, due to the departments' teaching responsibilities.
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Burgess, Mark. "Celebrating 50 years of Live Cell Imaging: Carl Zeiss UK and The Royal Microscopical Society, London, 15 October 2003." Biochemist 25, no. 6 (December 1, 2003): 46–48. http://dx.doi.org/10.1042/bio02506046.

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In 1930, Frits Zernike developed a way of making the invisible visible: he had perfected a method for the examination of living, unstained cells. The human eye and brain are good at distinguishing the amount of light (contrast) or its wavelength (colour), but are unable to distinguish differences in phase (there is no common name for it). Zernike had invented a technique that would make the invisible phase difference of a living cell a visible difference in light and shade. He took his invention, which he called phase contrast, to the greatest microscope manufacturer, Carl Zeiss, in 1932. Zeiss told him to get lost.
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15

Yattara-Baratti, C. L., V. Kehl, A. Kowert, H. G. Machens, A. Schilling, and C. I. Günter. "Retrospective long-term evaluation of the quality of life and the results of a modified transilluminated powered phlebectomy (TPP) technique." Phlebologie 44, no. 03 (May 2015): 139–47. http://dx.doi.org/10.12687/phleb2248-3-2015.

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ZusammenfassungEinleitung: Transilluminierte Powered Phlebektomie (TPP) mit der Trivex-Methode ist mittlerweile eine etablierte Methode zur Behandlung der Seitenastvaricosis. Untersuchungen mit Follow-up-Zeiten bis zu 2 Jahren zeigen, dass die TPP mit weniger Inzisionen auskommt und eine reduzierte Operations-zeit sowie verbesserte kosmetische Ergebnisse aufweist, als die herkömmliche Häkchenphlebektomie. Bisher lassen sich in der Literatur keine langfristigen Follow-up-Untersuchungen/Ergebnisse von mehr als 2 Jahren finden, zudem wurde bisher noch keine systematische Evaluation der gesundheitsbezogenen Lebensqualität nach TPP-Phlebektomie mittels SQOR-V Score durchgeführt.Material und Methode: Zwischen 2001–02 und 2009–05 wurden 627 Patienten mit Varizen mittels TPP, unter Verwendung einer modifizierten Operationstechnik, in der Praxisklinik Zollikerberg operiert. Insgesamt 141 Patienten dieser Patienten hatten bereits zuvor Krampfadernoperation mit verschiedenen nicht-TPP-Operationsmethoden erlebt. Diese 141 Patienten wurden im Rahmen einer retrospektiven Evaluation angeschrieben. SQOR-V und ein zusätzlicher neuer hausintern entwickelter TPP-Fragebogen wurden verwendet. 69 Patienten erklärten sich mit der Datenerhebung einverstanden (Informed Consent), beantworteten die Fragebögen und wurden in die Analyse inkludiert. Ergebnisse von TPP-Operation und nicht-TPP-Operationen wurden explorativ verglichen. Der postoperative Verlauf (6 Wochen) wurde analysiert, einschließ-lich Prä- und Post-OP-Foto-Dokumentation. Die Patienten wurden für eine Follow-up-Fotodokumentation und klinische Beurteilung in die Klinik eingeladen. 18 Patienten folgten dieser Einladung.Ergebnisse: Der Follow-Up-Zeitraum betrug maximal 8 Jahre und 2 Monate, minimal 2 Monate (Durchschnitt: 4,58 Jahre, Median: 4,25 Jahre). Der ästhetische Eindruck hatte sich bei 70 % der Patienten nach der TPP-OP mäßig bis sehr verbessert. 87 % der Patienten hatten keine oder lediglich eine minimale Reduktion der Aktivitäten nach der TPP-OP. Keine oder minimale Ödeme wurden von 60 % der Patienten nach der TPP-OP berichtet. Zwei Patienten mit peripherer Thrombose wurden nach TPP-OP beobachtet, aber keine tiefen Venenthrombose. Hingegen erlitten 6 Patienten bei der nicht-TPP-OP tiefe Beinvenenthrombosen. Nach der eigenen Erfahrung mit beiden Arten von Krampfader-Operationen berichteten die Patienten über signifikant weniger Schmerzen nach der TPP-OP (p=0,001). Sie waren statistisch signifikant häufiger mit den Ergebnissen des TPP-OP (82 %) als mit der nicht-TPP-OP (7 %) (p<0,001) zufrieden. Nach nicht-TPP-OPs hatten mehr Patienten Rezidiv-Varizen und venöse Ulzera als nach der TPP-OP (Rezidiv: nicht-TPP 100 % vs. TPP 42 % bzw., Ulcus: nicht-TPP 3 % vs. TPP 1,4 %). Hämatome waren nach der TPP-OP stärker ausgeprägt (starke 35,3 %, moderate 38,2 %) und dauerte länger an (>4 Wochen 39,4 %), als nach der nicht-TP-OP (23,9 %, 43,3 %, >4 Wochen 32,4 %). Pigmentierungen wurden häufiger nach der TPP-OP (31 %) als nach nicht-TPP-OP (18 %) beobachtet.Diskussion: Die Zufriedenheit mit den ästhetischen Ergebnissen der TPP-OP und die geringeren Schmerzen nach der TPP-OP waren statistisch signifikant besser als bei nichtTPP-OP. Klinisch wichtig ist die reduzierte Anzahl der Rezidiv-Varizen und die kleinere Zahl von Komplikationen nach der TPP-OP. Nachteilig sind die Hämatome und die Pigmentierungen, die jedoch überraschend gut toleriert wurden. Um diese vielversprechenden Ergebnisse zu bestätigen, sollten randomisierte klinische Studien durchgeführt werden.
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Clemens, M., M. Wilke, and T. Weiland. "Efficient extrapolation methods for electro- and magnetoquasistatic field simulations." Advances in Radio Science 1 (May 5, 2003): 81–86. http://dx.doi.org/10.5194/ars-1-81-2003.

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Abstract. In magneto- and electroquasi-static time domain simulations with implicit time stepping schemes the iterative solvers applied to the large sparse (non-)linear systems of equations are observed to converge faster if more accurate start solutions are available. Different extrapolation techniques for such new time step solutions are compared in combination with the preconditioned conjugate gradient algorithm. Simple extrapolation schemes based on Taylor series expansion are used as well as schemes derived especially for multi-stage implicit Runge-Kutta time stepping methods. With several initial guesses available, a new subspace projection extrapolation technique is proven to produce an optimal initial value vector. Numerical tests show the resulting improvements in terms of computational efficiency for several test problems. In quasistatischen elektromagnetischen Zeitbereichsimulationen mit impliziten Zeitschrittverfahren zeigt sich, dass die iterativen Lösungsverfahren für die großen dünnbesetzten (nicht-)linearen Gleichungssysteme schneller konvergieren, wenn genauere Startlösungen vorgegeben werden. Verschiedene Extrapolationstechniken werden für jeweils neue Zeitschrittlösungen in Verbindung mit dem präkonditionierten Konjugierte Gradientenverfahren vorgestellt. Einfache Extrapolationsverfahren basierend auf Taylorreihenentwicklungen werden ebenso benutzt wie speziell für mehrstufige implizite Runge-Kutta-Verfahren entwickelte Verfahren. Sind verschiedene Startlösungen verfügbar, so erlaubt ein neues Unterraum-Projektion- Extrapolationsverfahren die Konstruktion eines optimalen neuen Startvektors. Numerische Tests zeigen die aus diesen Verfahren resultierenden Verbesserungen der numerischen Effizienz.
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Baldwin, Jean, Ian S. Butler, and Denis F. R. Gilson. "Pressure tuning IR and micro-raman spectra of solid zeiseߣs salt, kp[pt(η-C2H4)Cl4], and the related dimer, [Pt(η-C2H4)Cl2]2." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1536–37. http://dx.doi.org/10.1017/s0424820100132315.

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Pressure-tuning vibrational spectroscopy using diamond-anvil cells is now well established as a useful technique for investigating the phase-transition behavior of inorganic and organic solids. Much of our recent research has been focused on organotransition metal compounds, especially metal carbonyls. The pressure dependences (dv/dP) of the v(CO) modes provide important information on the extent of #- backbonding between the metals and the carbonyl groups. We have now extended these high-presure studies to other #-acceptor ligands, including olefins. We report here the results of a high-pressure IR and micro-Raman spectroscopic investigation of the ethylene complexes, K[Pt(η-C2H4)C13] (Zeise's salt) and the related dimeric species, [Pt(η-C2H4)C12]2- We were interested in examining the effect of high pressures on the Dewar-Chatt-Ducanson σ-/π-bonding description of the platinum-ethylene bonding. There is still considerable controversy over the relative σ- and π-contributions to the overall bonding in such metal-olefin complexes.Micro-Raman spectra of solid K[Pt(η-C2H4)C13] were obtained at room temperature for the low-energy region (500-180 cm-1) at varying pressures up to 33 kbar with the aid of a diamond-anvil cell. Similarly, pressure-tuning IR spectra were measured for Zeise's salt (3080-480 cm-1; 32 kbar) and Zeise's dimer (4000-480 cm-1; 28 kbar) up to the pressures indicated.
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Ellzey, J. T., T. L. Stevens, D. Borunda, and D. C. Dominguez. "Comparison of manual and morphometric analysis techniques for rat hepatocyte peroxisomes." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 208–9. http://dx.doi.org/10.1017/s0424820100168773.

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It has been well documented that ethanol is toxic to hepatocytes and that peroxisomes are key organelles in the metabolism of ethanol. Lieber (1985) has confirmed that when rats are fed a 30% ethanol-derived calories diet for three weeks there are noticeable ultrastructural changes such as the accumulation of lipid (steatosis) and the hypertrophy of the smooth endoplasmic reticulum. We sought an efficient costeffective technique for obtaining reliable quantitative documentation of subtle changes within organelles of hepatocytes after rats were fed a 30% ethanol-derived calories diet for two weeks. One hundred micrographs of match paired ethanol-fed rats (n = 5) were compared with 100 micrographs of controls (n = 5) and analyzed by the point counting method; with a digital planimeter using SigmaScan/Image software (Jandel Inc.) and calculations were made using Excel v. 4.0 (Microsoft Corp.); as well as with Optimas image analysis software (Bioscan). Micrographs were taken with a Zeiss EM 10 transmission electron microscope.
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Yaremenko, A. I., E. A. Zernitskaya, P. A. Zotov, Yu Yu Karlagina, E. E. Egorova, and G. V. Odintsova. "Experimental study of the Ti-implant surfaces structured by the ytterbium-doped pulsed fiber laser." Parodontologiya 26, no. 2 (June 30, 2021): 88–95. http://dx.doi.org/10.33925/1683-3759-2021-26-2-88-95.

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Relevance. Currently, there are several basic techniques for the dental implant surface structuring. Laser treatment is an extremely promising technique for the surface structuring. This technology allows creating regular implant surface without using chemicals and in just one technological step. The purpose was to present study aimed to compare and evaluate in vivo the stability and osseointegration of dental implants with 2 different surfaces structured by ytterbium-doped pulsed fiber laser operating at 1064 nm.Materials and methods. 60 dental implants were placed in the study. 2 types of dental implant surfaces, namely holes and parallel grooves, were created by the ytterbium laser operating at 1064 nm. A polished dental implant (without laser surface structuring) was also included in the experiment for comparison. The study was carried out on 15 laboratory animals (male rabbits, weight 3.5-4 kg). The implants were placed in the tibia. 4 implants with different surface types but of the same diameter and length were placed in each rabbit.Results. Laboratory animals were sacrificed 1.5 and 3 months after the surgery. The stability of the implants was assessed by RFA (Resonance Frequency Analysis), based on the registration of resonance electromagnetic oscillations of the implant and the surrounding bone when they are exposed to the electromagnetic field (Osstell ISQ). Also, nondecalcified bone blocks were histologically examined using a confocal laser scanning microscope (Carl Zeiss LSM 780) and histomorphometry was performed (BIC-index: Bone-to-implant contact). Bone blocks were prepared according to a special technique: they were soaked and embedded into the plastic and synthetic resin. The obtained blocks were cut into sections, 40-50 µm thick, and stained with toluidine blue.Conclusion. Laser surface structuring of the dental titanium implants is a promising technique. 59 in 60 (98.3%) implants were osseointegrated, there were no signs of inflammation in the bone tissue. The present results allow further studying of dental implants with various surface designs, structured by ytterbium laser.
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Jumahat, Aidah, Constantinos Soutis, Nor Merlisa Ali, and Jamaluddin Mahmud. "Fibre Misalignment Measurement of Nanomodified-Unidirectional Carbon Fibre Laminates." Applied Mechanics and Materials 393 (September 2013): 200–205. http://dx.doi.org/10.4028/www.scientific.net/amm.393.200.

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This paper investigates the effect of nanosilica on the fibre waviness or misalignment angle distribution of carbon fibre reinforced polymer composite unidirectional laminates. The quality of the laminates was evaluated using image analyzer technique. The polished specimens were examined using Polyvar B-met optical microscope and analysed using KSRUN ZEISS software. The effect of 3, 7 and 13 vol.% nanosilica on the fibre misalignment angle distribution was determined. The results showed that, the fabricated laminates have average fibre volume fractionVfof 42%, low fibre waviness distribution (averageφo= 2.5o) and less than 1% void content. This implies that the fabrication technique, which was employed in the current work, successfully produced good quality laminates. The presence of nanosilica results in a narrow fibre angle distribution in the HTS40/828 laminate.
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Balle, Bernd. "Measuring means knowledge." Advanced Technologies in Mechanics 3, no. 1(6) (March 2, 2017): 24. http://dx.doi.org/10.17814/atim.2016.1(6).37.

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Optical designers, physicists and engineers at FISBA develop, analyze and optimize optical components on behalf of their customers. Thanks to its innovative production techniques, the Swiss company is widely renowned as a manufacturer of highquality optical components and systems. A ZEISS MICURA coordinate measuring machine is among the tools used by the company to ensure the quality that is valued around the globe.
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Amerian, Y., and B. Voosoghi. "Least Squares Spectral Analysis for Detection of Systematic Behaviour of Digital Level Compensator." Journal of Geodetic Science 1, no. 1 (March 1, 2011): 35–40. http://dx.doi.org/10.2478/v10156-010-0005-4.

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Least Squares Spectral Analysis for Detection of Systematic Behaviour of Digital Level CompensatorLevelling is the most precise technique for height difference measurements in geomatics engineering. Various systematic errors affect precise levelling observations and reduce the precision of the observed height differences. This study investigates digital levels residual compensator error and observational method for its elimination. For this purpose the levelling data, which was collected with Zeiss DiNi 12 digital levels, was analysed. There are different statistical and spectral methods that can reveal the presence of systematic errors in levelling results. In this study, the Least Squares Spectral Analysis (LSSA) method is used. The analysis confirmed that using alternating pointing method (BFFB, FBBF) instead of usual observation routine (BFFB) will eliminate the Zeiss DiNi 12 digital levels residual compensator error from section height differences and discrepancies. In this way, it does not matter using different instruments in the forward and backward section runs and the discrepancies can be used to investigate other systematic errors.
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Kisselev, A. A., O. P. Bykov, O. A. Kalinichenko, O. V. Kiyaeva, L. G. Romanenko, and N. A. Shakht. "The Pulkovo Programme for the Study of Visual Double Stars." Symposium - International Astronomical Union 141 (1990): 63–64. http://dx.doi.org/10.1017/s0074180900086174.

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The observation of visual double stars at Pulkovo is a traditional work of Pulkovo astronomers started by W. Struve in 1830 at Dorpat (now Tartu). After the Second World War and restoration of the observatory in 1960, the observations of double stars have been carried out with help of 26-inch Zeiss refractor using the photographic technique. We observe the visual binaries which satisfy the conditions of highest accuracy of astrometric reduction: d > 3′, m < 12.0, dm < 1.0, δ>20°.
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KHADIJA KHLEAF AL-DULAIMI. "The prevalence of the Cryptosporidium parvum among children in Ramadi city." Tikrit Journal of Pure Science 27, no. 3 (November 30, 2022): 1–5. http://dx.doi.org/10.25130/tjps.v27i3.58.

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The purpose of this study was to determine the prevalence of Cryptosporidium parvum among children in the city of Ramadi and made a comparison between ziehl -Neelsen method and the ELISA method, which is usually used to diagnose this parasite in Ramadi hospital (administration of Obstetrics and Gynecology Hospital and Ramadi Teaching Hospital). Fecal samples were collected from 813 children under 5 years. Oocysts of Cryptosporidium parvum parasite were determined by using ELSIA and Ziehl-Neelsen (acid-fast stain, ZN). Our study was shown that the rate of prevalence of the C. parvum was 7.87% from the total of 813 samples of diarrhea by using Zeihl-Neelsen method while ELISA technique result was 11.56% From our results, ELISA technique more specific than Ziehl-Neelsen method in diagnosis of C. parvum and the different is significant (P <0.05)..
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Chestnut, H., D. P. Siegel, J. L. Burns, and Y. Talmon. "A temperature-jump technique for time-resolved cryo-transmission Electron Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 742–43. http://dx.doi.org/10.1017/s0424820100155682.

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Transmission electron microscopy of rapidly-frozen, hydrated specimens (cryo-TEM) is a powerful way of examining labile microstructures. This technique avoids some artifacts associated with conventional preparative methods. Use of a controlled environment vitrification system (CEVS) for specimen preparation reduces the risk of unwanted sample changes due to evaporation, and permits the examination of specimens vitrified from a defined temperature. Studies of dynamic processes with time resolution on the order of seconds, in which the process was initiated by changes in sample pH, have been conducted. We now report the development of an optical method for increasing specimen temperature immediately before vitrification. Using our method, processes that are regulated by temperature can be initiated in less than 500 msec on the specimen grid. The ensuing events can then be captured by plunge-freezing within an additional 200 msec.Dimyristoylphosphatidylcholine (DMPC) liposomes, produced by extrusion, were used as test specimens. DMPC undergoes a gel/liquid crystalline transition at 24°C, inducing a change in liposome morphology from polyhedral to spherical. Five-μl aliquots of DMPC dispersions were placed on holey-carbon-filmed copper grids mounted in the CEVS environmental chamber, and maintained at 6-8°C and 80% relative humidity. Immediately before the temperature jump most of the sample was blotted away with filter paper, leaving a thin specimen film on the grid. Upon pressing the trigger, an electronic control circuit generated this timed sequence of events. First, a solenoid-activated shutter was opened to heat the specimen by exposing it for a variable time to the focused beam of a 75W Xenon arc lamp. Simultaneously, a solenoid-activated cryogen shutter in the bottom of the CEVS was opened. Next, the lamp shutter was closed after the desired heating interval. Finally, a solenoid-activated cable release was used to trigger a spring-loaded plunger in the CEVS, propelling the sample into a reservoir of liquid ethane. Vitrified samples were subsequently transferred to a Zeiss EM902 TEM, operated in zero-loss brightfield mode, for examination at −163°C.
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Gossett, Eric M., Ellen B. Scanley, Yanhui Liu, Yanglin Li, Ze Liu, Sungwoo Sohn, Jan Schroers, Christine Broadbridge, and Todd C. Schwendemann. "Computational Nanocharacterization for Combinatorially Developed Bulk Metallic Glass." International Journal of High Speed Electronics and Systems 24, no. 03n04 (September 2015): 1520012. http://dx.doi.org/10.1142/s0129156415200128.

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Bulk metallic glasses synthesized at specialized facilities at Yale using magnetron cosputtering are sent to Southern Connecticut State University for elemental characterization. Characterization is done using a Zeiss Sigma VP SEM coupled with an Oxford EDS. Characterization is automated using control software provided by Oxford. Collected data is processed and visualized using computational methods developed internally. Processed data is then organized into a database suitable for web retrieval. This technique allows for the rapid characterization of a combinatorial wafer to be carried out in ~11 hours for a single wafer containing ~600 unique compounds.
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TS, Kaluarachchi. "Novel Technique of 23G Pars Planar Vitrectomy (TPPV) with Alcon Centurion Silver System Gravity -FMS (ACenSS) and ACenSS Vitrectomy Probe (23G) with an External Light Source in Teaching Hospital Rathnapura Sri Lanka." Open Access Journal of Ophthalmology 7, no. 2 (July 1, 2022): 1–7. http://dx.doi.org/10.23880/oajo-16000249.

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Dual pneumatic 23G vitrectomy cutters of both Alcon Constellation Vision System (AConsVS) and ACenSS have cut rates of 5000 cpm. Aims: To report a novel technique of using ACenSS 23G Vitrectomy cutter for trocar surgery with an external light source in Teaching hospital Rathnapura Sri Lanka from 01/03/2022 to 30/09/2022. Methods: 23G Alcon light probes were used with Retikare (ICON Medicare Tamil Nadu India) external light source for endoillumination. Infusion pressure was set at 65cmH2O (47.81 mmHg) and infusion line connected to eye through a 3 ways tap. ACenSS-GFMS aspiration line connected to aspiration line of vitrectomy probe. Cryopexy used to seal retinal tears as no endolaser facility. Volk surgical corneal lenses with Zeiss Lumera I microscope provided the viewing. ACenSS foot pedal was programmed to 3 modes of vitrectomy with navigation, cutter on/ off function and on/pause of continuous irrigation. A gravity driven another infusion line is used to keep the infusion when endo diathermy is used. Results: When working on maximum cut rate of the ACenSS GFMS (5000 cpm) for long duration machine automatically stops and a restart with reprime needed. Therefore, cut rates were set at a lower rate to work without interruption (core vitrectomy2000 cpm, peripheral trim- 3000cpm and for epinucleus removal 4000 cpm). No retinal traction or ridging of retina was observed at peripheral trim. Total of 210 TPPVs were performed with this technique. Conclusions: 23G TPPV with ACenSS using an external light source is a simple, safe and a cost-effective technique with equal outcome to AConsVS.
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Zschech, Ehrenfried, Sven Niese, Markus Löffler, and M. Jürgen Wolf. "Multi-scale X-ray tomography for process and quality control in 3D TSV packaging." International Symposium on Microelectronics 2014, no. 1 (October 1, 2014): 000184–87. http://dx.doi.org/10.4071/isom-tp12.

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Advanced packaging processes and the resulting 3D products challenge process and quality control. X-ray imaging and X-ray computed tomography (XCT) provide non-destructive characterization capabilities on specimens across a range of length scales, observing features with sizes spanning from millimeters over micrometers down to several 10 nanometers. They are the techniques of choice for two- or three-dimensional inspection of medium and small sized objects with a resolution down to several 10 nm. In this paper, the potential and the limits of XCT for process development, process monitoring, and failure analysis in 3D TSV stacks are described. It is shown that a multi-scale approach, i.e. using imaging techniques with several resolution ranges, is necessary for these particular tasks. Since sub-micron XCT and nano XCT are very useful techniques with a promising prospect for the future, we focus on the capabilities of two lab-based XCT tools with sub-micron resolution (Zeiss Versa) and with &lt; 50 nm resolution (Zeiss Ultra). We demonstrate the capabilities for nondestructive imaging of multi-die stacks with TSVs and AgSn microbumps. Major filling defects in TSVs are clearly visualized. An analysis of individual bumps reveals mismatches in relative positioning, micron-size pores, and the distribution of intermetallic phases. This information provides important information regarding the respective process steps (process control) and the product quality (quality control). In addition, TSV etch profiles and small voids in Cu TSVs are visualized. Since deviations from the targeted geometry and defects are difficult to locate precisely from a two-dimensional image, X-ray computed tomography has to be applied.
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Bastidas-Rodríguez, Maria Ximena, Flavio A. Prieto-Ortíz, and Édgar Espejo-Mora. "Fractographic classification in metallic materials by using 3D processing and computer vision techniques." Revista Facultad de Ingeniería 25, no. 43 (September 1, 2016): 83–96. http://dx.doi.org/10.19053/01211129.v25.n43.2016.5301.

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Failure analysis aims at collecting information about how and why a failure is produced. The first step in this process is a visual inspection on the flaw surface that will reveal the features, marks, and texture, which characterize each type of fracture. This is generally carried out by personnel with no experience that usually lack the knowledge to do it. This paper proposes a classification method for three kinds of fractures in crystalline materials: brittle, fatigue, and ductile. The method uses 3D vision, and it is expected to support failure analysis. The features used in this work were: i) Haralick’s features and ii) the fractal dimension. These features were applied to 3D images obtained from a confocal laser scanning microscopy Zeiss LSM 700. For the classification, we evaluated two classifiers: Artificial Neural Networks and Support Vector Machine. The performance evaluation was made by extracting four marginal relations from the confusion matrix: accuracy, sensitivity, specificity, and precision, plus three evaluation methods: Receiver Operating Characteristic space, the Individual Classification Success Index, and the Jaccard’s coefficient. Despite the classification percentage obtained by an expert is better than the one obtained with the algorithm, the algorithm achieves a classification percentage near or exceeding the 60 % accuracy for the analyzed failure modes. The results presented here provide a good approach to address future research on texture analysis using 3D data.
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Dorner, G. T., G. Garhoefer, C. Zawinka, B. Kiss, and L. Schmetterer. "Response of Retinal Blood Flow to CO2-Breathing in Humans." European Journal of Ophthalmology 12, no. 6 (November 2002): 459–66. http://dx.doi.org/10.1177/112067210201200603.

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Purpose To investigate the effect of systemic hypercapnia on retinal hemodynamics in humans. Methods We studied the effect of breathing a mixture of normal air with 5% CO2 for 13 minutes in ten healthy young male volunteers, using the Zeiss retinal vessel analyzer for continuous measurement of retinal vessel diameter and the blue-field entoptic technique to quantify retinal white blood cell flux. In eight other subjects the effect of hypercapnia was measured with the Zeiss retinal vessel analyzer and by laser Doppler velocimetry to establish retinal blood flow velocity. Results Retinal arterial and venous vessel diameters increased by a maximum of 4.2% and 3.2%, respectively. Peak effect was observed after 3 minutes of breathing the mixture of normal air with 5% CO2. During hypercapnia red blood cell velocity increased 11.7% and, accordingly, retinal blood flow increased 19.1%. White blood cell density and velocity rose significantly during hypercapnia, resulting in an increase in white blood cell flux (19.2%). Conclusions Our data indicate that CO2 induces vasodilation in retinal arteries and retinal veins. Retinal blood flow and perimacular white blood cell flux increased to the same extent in subjects breathing a mixture of normal air with 5% CO2.
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Raabe, Andreas, Peter Nakaji, Jürgen Beck, Louis J. Kim, Frank P. K. Hsu, Jonathan D. Kamerman, Volker Seifert, and Robert F. Spetzler. "Prospective evaluation of surgical microscope—integrated intraoperative near-infrared indocyanine green videoangiography during aneurysm surgery." Journal of Neurosurgery 103, no. 6 (December 2005): 982–89. http://dx.doi.org/10.3171/jns.2005.103.6.0982.

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Object. The authors prospectively compared a new technique of surgical microscope-based indocyanine green (ICG) videoangiography with intraoperative or postoperative digital subtraction (DS) angiography. Method. The technique was performed during 187 surgical procedures in which 124 aneurysms in 114 patients were clipped. Using a newly developed setup, the ICG technique has been integrated into an operating microscope (Carl Zeiss Co., Oberkochen, Germany). A microscope-integrated light source containing infrared excitation light illuminates the operating field. The dye is injected intravenously into the patient, and intravascular fluorescence from within the blood vessels is imaged using a video camera attached to the microscope. The patency of parent, branching, and perforating arteries and documentation of clip occlusion of the aneurysm as shown by ICG videoangiography were compared with intraoperative or postoperative findings on DS angiography. The results of ICG videoangiography corresponded with intra- or postoperative DS angiography in 90% of cases. The ICG technique missed mild but hemodynamically irrelevant stenosis that was evident on DS angiography in 7.3% of cases. The ICG technique missed angiographically relevant findings in three cases (one hemodynamically relevant stenosis and two residual aneurysm necks [2.7% of cases]). In two cases the missed findings were clinically and surgically inconsequential; in the third case, a 4-mm residual neck may require a second procedure. Indocyanine green videoangiography provided significant information for the surgeon in 9% of cases, most of which led to clip correction. Conclusions. Microscope-based ICG videoangiography is simple and provides real-time information about the patency of vessels of all sizes and about the aneurysm sac. This technique may be useful during routine aneurysm surgery as an independent form of angiography or as an adjunct to intra- or postoperative DS angiography.
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Cauduro, Ricardo Salles, Caroline do Amaral Ferraz, Maira Saad Ávila Morales, Patricia Novita Garcia, Yara Cristina Lopes, Paulo Henrique Souza, and Norma Allemann. "Application of Anterior Segment Optical Coherence Tomography in Pediatric Ophthalmology." Journal of Ophthalmology 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/313120.

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Purpose.Application of anterior segment optical coherence (AS-OCT) in pediatric ophthalmology.Methods.Retrospective clinical study case series of 26 eyes of 19 pediatric patients throughout a 21-month period, presenting anterior segment pathologies, were submitted to AS-OCT examination (OCT Visante, 1310 nm, Zeiss), noncontact technique, no sedation requirement.Results.AS-OCT images were obtained from 19 patients (range: 2 months to 12 years). Clinical diagnosis of anterior segment abnormalities included cornea disease (n=7), congenital anterior segment conditions (n=10), ocular trauma (n=1), anterior segment surgeries (n=2), iridocorneal angle abnormalities (n=4), intermediate uveitis (n=2). The most common OCT findings were corneal hyperreflectivity and thickening (n=15), shallow anterior chamber with iris-lens diaphragm anterior displacement (n=4), atypical corneal curvature (n=4), corneal thinning (n=4), peripheral synechiae with angle closure (n=3), increased anterior chamber depth (n=2), and proximal portion of glaucoma drainage tube (n=2).Conclusion.In the present study, noncontact AS-OCT demonstrated to be a feasible technique to evaluate the anterior segment providing anatomic details and useful to clarify diagnosis in the pediatric population.
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Weyand, Björn. "Die Welt als zu bereisender Katalog.: Enumerative Verfahren der Reiseliteratur bei Adam Olearius, Johann Wolfgang Goethe und Otto Julius Bierbaum." Zeitschrift für Germanistik 32, no. 1 (January 1, 2022): 61–84. http://dx.doi.org/10.3726/92171_61.

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Reiseliteratur und enumerative Verfahren sind seit der Antike eng miteinander verflochten. Der Beitrag entwickelt eine mediengebundene Differenzierung zwischen Aufzählung, Liste und Katalog. Analysen von Adam Olearius’ Gottorfische Kunst=Kammer, Johann Wolfgang Goethes Italienische Reise und Otto Julius Bierbaums Yankeedoodle=Fahrt zeigen, wie sich die enumerativen Schreibweisen der Reiseliteratur vor dem Hintergrund kultur-, medien- und wissensgeschichtlicher Entwicklungen verändern. Travel literature and enumerative practices have been closely intertwined since antiquity. The article develops a media-bound differentiation between enumerations, lists, and catalogues. Analyses of Adam Olearius’ Gottorfische Kunst=Kammer, Johann Wolfgang Goethe’s Italienische Reise, and Otto Julius Bierbaum’s Yankeedoodle=Fahrt, show how enumerative techniques in travel literature have changed against the background of developments in the history of culture, media, and knowledge.
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Weis, Rüdiger. "Vertrauen aus Mathematik." Zeitschrift für Medien- und Kulturforschung 10, no. 2 (2019): 109–15. http://dx.doi.org/10.28937/1000108355.

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"In Zeiten, in denen jahrzehntelang stabile Vertrauensverhältnisse global immer stärker erschüttert werden, suchen die Menschen nach neuen Vertrauensansätzen. Die libertäre Philosophie hinter Bitcoin nutzt einfache und verständliche Techniken aus der Mathematik, um ein Währungssystem ohne Banken und Staaten zu schaffen. Durch die Geschwindigkeit und die weltweite Verfügbarkeit von Kommunikationsnetzen findet somit ein völlig neuartiges gesellschaftliches Experiment statt. In times in which stable relationships of trust have been increasingly shaken around the globe for decades, people are looking for new approaches to the ability to trust. The libertarian philosophy behind Bitcoin uses simple and understandable mathematical techniques to create a monetary system without banks and states. The speed and worldwide avail- ability of communication networks thus make for a completely new social experiment."
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BULAT, TANJA, OTILIJA KETA, LELA KORIĆANAC, JELENA ŽAKULA, IVAN PETROVIĆ, ALEKSANDRA RISTIĆ-FIRA, and DANIJELA TODOROVIĆ. "Radiation dose determines the method for quantification of DNA double strand breaks." Anais da Academia Brasileira de Ciências 88, no. 1 (March 4, 2016): 127–36. http://dx.doi.org/10.1590/0001-3765201620140553.

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ABSTRACT Ionizing radiation induces DNA double strand breaks (DSBs) that trigger phosphorylation of the histone protein H2AX (γH2AX). Immunofluorescent staining visualizes formation of γH2AX foci, allowing their quantification. This method, as opposed to Western blot assay and Flow cytometry, provides more accurate analysis, by showing exact position and intensity of fluorescent signal in each single cell. In practice there are problems in quantification of γH2AX. This paper is based on two issues: the determination of which technique should be applied concerning the radiation dose, and how to analyze fluorescent microscopy images obtained by different microscopes. HTB140 melanoma cells were exposed to γ-rays, in the dose range from 1 to 16 Gy. Radiation effects on the DNA level were analyzed at different time intervals after irradiation by Western blot analysis and immunofluorescence microscopy. Immunochemically stained cells were visualized with two types of microscopes: AxioVision (Zeiss, Germany) microscope, comprising an ApoTome software, and AxioImagerA1 microscope (Zeiss, Germany). Obtained results show that the level of γH2AX is time and dose dependent. Immunofluorescence microscopy provided better detection of DSBs for lower irradiation doses, while Western blot analysis was more reliable for higher irradiation doses. AxioVision microscope containing ApoTome software was more suitable for the detection of γH2AX foci.
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Wei, Sheng Jun, and Nancy R. Smith. "The application of electronspectroscopic imaging (ESI) in biological studies." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 500–501. http://dx.doi.org/10.1017/s0424820100170232.

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Electronspectroscopic imaging (ESI) offers a means of filtered imaging of specimens resulting in high resolution and depth of field with optimum constrast. Using an integrated imaging electron energy spectrometer (integrated prism/mirror/prism) in a Zeiss-902A transmission electron microscope (TEM), it is possible to select unscattered electrons (ΔE=OeV) or inelastically scattered electrons (ΔE>OeV) to observe biological structures of interest. The contrast in biological specimens is enhanced bythis technique and unstained, ultrathin sections and thick sections can be imaged with optimum contrast and high resolution. This technology can solve many of the problems encountered with staining biological samples (e.g. precipitates or poor contrast) and has proven to be superior to the conventional TEM (CTEM) in many aspects. Virus particles in cultured cells are clearly observed without post-staining. Unstained lipsome and other drug delivery systems can be viewed and measured without negative staining and subsequent deformation and as a result, more accurate sizing information can be obtained. Granules and enzyme reacted precipitates inside unstained cells and tissues can also be observed without staining. Sections that are stained yield finer details than those imaged by CTEM. Figures 1 through 8 obtained with the Zeiss-902A show the quality of ESI and the advantages of using this system of imaging biological specimens.
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Dagne, Nigus, and Amir Alelign. "Prevalence of Intestinal Protozoan Parasites and Associated Risk Factors among School Children in Merhabete District, Central Ethiopia." Journal of Parasitology Research 2021 (November 25, 2021): 1–7. http://dx.doi.org/10.1155/2021/9916456.

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Background. Intestinal protozoan parasitic infections remain one of the major public health problems in tropical regions especially, among developing countries such as Ethiopia. However, no enough epidemiological data is available in this respect in many parts of the country. Hence, this study was aimed at assessing the prevalence of intestinal protozoan parasitic infections and their associated risk factors among school children in Zeita village, Merhabete District, North Shewa Zone, Central Ethiopia. Methods. A cross-sectional parasitological survey was conducted from January to March 2020. A total of 280 children from Zeita primary school were selected using stratified random sampling techniques. Stool samples were collected and examined using direct wet mount, Formal-Ether concentration and Modified Zeihel-Neelsen staining techniques. Results. The overall prevalence of intestinal protozoan parasitic infection was found to be 46.8% (131/280). The three predominant protozoan parasites detected in this study were Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum which were observed in 70 (25.2%), 54 (19.3%), and 7 (2.5%) of the study participants, respectively. Sociodemographic characteristics of the study subjects such as family occupation ( P = 0.028 ), sources of drinking water ( P = 0.001 ), water handling practice ( P = 0.027 ), habit of eating vegetable ( P = 0.001 ), and presence of latrine were observed to be significantly associated risk factors for the occurrence of human intestinal protozoan parasites. Conclusion. A high prevalence of intestinal protozoan parasitic infection which has been contributed by different risk factors was revealed in this study. The findings suggested a need of collaborative effort among the educational and health authorities to control the infection in the study area.
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Wiederhold, Dietmar. "Effekte einer Klopftechnik zur Reduktion von Stress, Angst und Burnout." Dialyse aktuell 25, no. 07 (September 2021): 260–61. http://dx.doi.org/10.1055/a-1401-2739.

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Mit dem Ausbruch der COVID-19-Pandemie haben Pflegekräfte an vorderster Front eine hohe Verantwortung für die Pflege und Behandlung von schwer kranken Patienten übernommen. Das Erleben der Patientenschicksale auf der einen und die eigenen familiären Verpflichtungen auf der anderen Seite haben enorme Auswirkungen auf die psychische Gesundheit mit sich gebracht. So wurde ein hohes Maß an Hilflosigkeit, Schlafstörungen, Ängsten, Stress, Burnout und Depressionen bei den Beschäftigten im Gesundheitswesen beobachtet. 98 % der Wirksamkeitsstudien zeigen statistisch signifikante Verbesserungen der psychischen Belastungen, wenn die Emotional-Freedom-Technique (EFT) angewendet wird. Dabei handelt es sich um eine Klopftechnik von Akupressurpunkten der Traditionellen Chinesischen Medizin (TCM), mit welcher durch eigene körperliche Stimulation ausgleichende und harmonisierende Effekte auf Geist und Emotionen erzeugt werden sollen. In der vorliegenden Studie wurde die Wirksamkeit von EFT auf die Prävention von Stress, Angst und Burnout bei Pflegekräften in der Versorgung von COVID-19-Patienten untersucht.
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Rahmanian, Abdolkarim. "Microsurgical Training Curriculum for Neurosurgery Residents in Southern Iran." Iranian Journal of Neurosurgery 6, no. 3 (July 1, 2020): 165–68. http://dx.doi.org/10.32598/irjns.6.3.9.

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Cerebrovascular diseases comprise a major subspecialty in neurological surgery. Current education curriculums lack the necessary training modalities for teaching the microvascular techniques, to neurosurgery residents. We have included a 1-month micro-lab and animal lab rotation for senior residents, which can be added to their current educational program. Necessary equipment for this rotation includes an operating microscope Zeiss S8, microsurgical instruments, and animal anesthesia equipment are used to perform revascularization techniques on the aorta of a rat model (average-sized Sprague-Dawley weighing 200-250 gram). This rotation was included in previous curriculums as micro-lab. Evaluation of microvascular surgical skills following the addition of animal models to this skill lab is suggested to be considered as a part of OSCE in board certification in future studies. The addition of animal models to micro-lab rotations, provides a better understanding of tissue consistency while dealing with a microvascular surgery procedure, for neurological surgery residents.
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Gu, H., J. Mayer, H. Müllejans, and M. Rühle. "Applications of high-spatial-resolution microanalysis in materials science." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 976–77. http://dx.doi.org/10.1017/s0424820100172619.

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The development of advanced materials frequently requires control over the presence and propertiesof interfaces. In order to establish the relationship between the microstructure and the macroscopic behaviour of the material both, the structure and the composition of the interfaces have to be revealed at a resolution at or close to the atomic level. In this paper new techniques in analytical electron microscopy with high spatial resolution will be discussed. The analysis is based on electron energy-loss spectroscopy (EELS). Spatial resolution can either be obtained by applying an energy filteringTEM (EFTEM) or a small probe in a field emission dedicated STEM. Both techniques have been applied toa number of model systems and the achievable detection and resolution limits will be compared. The experimental studies were performed at (i) a Zeiss EM 912 Omega instrument equipped with a 1024 × 1024 slow scan CCD camera and (ii) a VG HB 501 equipped with parallel EELS.
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41

Vossen, Robbert van, Andrew Curtis, and Jeannot Trampert. "Subsonic near-surface P-velocity and low S-velocity observations using propagator inversion." GEOPHYSICS 70, no. 4 (July 2005): R15—R23. http://dx.doi.org/10.1190/1.1990220.

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Detailed knowledge of near-surface P- and S-wave velocities is important for processing and interpreting multicomponent land seismic data because (1) the entire wavefield passes through and is influenced by the near-surface soil conditions, (2) both source repeatability and receiver coupling also depend on these conditions, and (3) near-surface P- and S-wave velocities are required for wavefield decomposition and demultiple methods. However, it is often difficult to measure these velocities with conventional techniques because sensitivity to shallow-wave velocities is low and because of the presence of sharp velocity contrasts or gradients close to the earth's free surface. We demonstrate that these near-surface P- and S-wave velocities can be obtained using a propagator inversion. This approach requires data recorded by at least one multicomponent geophone at the surface and an additional multicomponent geophone at depth. The propagator between them then contains all information on the medium parameters governing wave propagation between the geophones at the surface and at depth. Hence, inverting the propagator gives local estimates for these parameters. This technique has been applied to data acquired in Zeist, the Netherlands. The near-surface sediments at this site are unconsolidated sands with a thin vegetation soil on top, and the sediments considered are located above the groundwater table. A buried geophone was positioned 1.05 m beneath receivers on the surface. Propagator inversion yielded low near-surface velocities, namely, 270 ± 15 m/s for the compressional-wave velocity, which is well below the sound velocity in air, and 150 ± 9 m/s for the shear velocity. Existing methods designed for imaging deeper structures cannot resolve these shallow material properties. Furthermore, velocities usually increase rapidly with depth close to the earth's surface because of increasing confining pressure. We suspect that for this reason, subsonic near-surface P-wave velocities are not commonly observed.
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42

Kanse, Shilpa Sameer, and Dinkar Manik Yadav. "Retinal Fundus Image for Glaucoma Detection: A Review and Study." Journal of Intelligent Systems 28, no. 1 (January 28, 2019): 43–56. http://dx.doi.org/10.1515/jisys-2016-0258.

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Abstract Glaucoma is one of the severe visual diseases that lead to damage the eyes irreversibly by affecting the optic nerve fibers and astrocytes. Consequently, the early detection of glaucoma plays a virtual role in the medical field. The literature presents various techniques for the early detection of glaucoma. Among the various techniques, retinal image-based detection plays a major role as it comes under noninvasive methods of detection. While detecting glaucoma disorder using retinal images, various medical features of the eyes, such as retinal nerve fiber layer, cup-to-disc ratio, apex point, optic disc, and optic nerve head, and image features, such as Haralick texture, higher-order spectra, and wavelet energy, are used. In this paper, a review and study were conducted for the different techniques of glaucoma detection using retinal fundus images. Accordingly, 45 research papers were reviewed and the analysis was provided based on the extracted features, classification accuracy, and the usage of different data sets, such as DIARETDB1 data set, MESSIDOR data set, IPN data set, ZEISS data set, local data set, and real data set. Finally, we present the various research issues and solutions that can be useful for the researchers to accomplish further research on glaucoma detection.
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43

Romek, M., B. Gajda, E. Krzysztofowicz, and Z. Smorag. "91 A NOVEL TECHNIQUE FOR EVALUATION OF THE LIPID CONTENT IN PIG EMBRYOS." Reproduction, Fertility and Development 20, no. 1 (2008): 126. http://dx.doi.org/10.1071/rdv20n1ab91.

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A high level of lipids, mainly triglycerides and fatty acids, present in embryo cells in the form of lipid droplets is the major factor associated with low cryopreservation of porcine embryos. Previous results demonstrated that the low tolerance of pig embryos to cryopreservation can be increased through reduction of lipid droplet contents. Therefore, in order to improve cryopreservation techniques of porcine embryos, it is fundamental to establish proper culture conditions which ultimately will enable a decrease in lipid content. Unfortunately, there are no precise and efficient methods to evaluate the lipid contents of single pig embryos. Previously used stereological analysis combined with physical serial sectioning (Romek et al. 2007 Reprod. Domest. Anim. in press) is time-consuming, and measurement of triglyceride levels based on enzymatic hydrolysis eliminates other types of lipids from the analysis. Taking the above problems into account, we have developed a new method for evaluation of total lipid content in pig embryos. It is based on visualization of lipid droplets using the specific fluorescent dye Nile red and applying confocal scanning microscopy followed by the Cavalieri method. This method enables measurement of several stereological parameters, especially the volume density of lipid droplets per unit volume of cytoplasm Vv(fat,c), which quantifies most precisely the amount of intracellular lipid. The experiment was carried out on 2- to 4-cell and 8- to 16-cell pig embryos, morulae, blastocysts, and late blastocysts cultured in vitro. Embryos were developed from in vivo-produced zygotes to appropriate stages of development in North Carolina State University (NCSU) 23 medium. For each stage, ten of the embryos were examined. Embryos were denuded and fixed with 2% glutaraldehyde and 2% formaldehyde, stained with 100 nm Nile red (Molecular Probes, Leiden, The Netherlands), and analyzed by means of a confocal microscope LSM 510 Meta (Carl Zeiss MicroImaging GmbH, G�ttingen, Germany). Serial optical sections of each individual embryo were measured by the point counting method, and then the Cavalieri method was used to estimate Vv(fat,). Vv(fat,c) values calculated for embryos at different stages of development were compared by one-way analysis of variance and Tukey's intervals. For cultured pig embryos, volume density of lipid droplets Vv(fat,c) significantly decreased during cleavage from 0.55 µm3 µm–3 at the 2- to 4-cell-embryo stage to 0.46 µm3 µm–3 at the blastocyst stage. The differences between lipid droplet volumes calculated for morulae, blastocysts, and late blastocysts were statistically significant. In conclusion, our new method is more precise, efficient, and quick in comparison to previously used ones. Moreover, we confirmed that the content of total lipids in cultured pig embryo is reduced during its development. This research was funded by the State Committee for Scientific Research (Project No. 2 P06D 003 26) and Net of Reproduction Biotechnology.
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44

Zavgorodnia, N. G., Yu Yu Doroshenko, T. S. Zavgorodnia, I. O. Poplavska, K. O. Kostrovska, and N. S. Kryvobok. "Efficacy of LASIK and LASEK methods in achieving the predicted result in excimer laser correction of myopia and myopic astigmatism." Archive of Ukrainian Ophthalmology 8, no. 3 (April 22, 2021): 19–23. http://dx.doi.org/10.22141/2309-8147.8.3.2020.220450.

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Excimer laser correction of refraction anomalies has entered ophthalmological practice as one of the most effective surgical techniques, which allows us to correct refractive errors by changing corneal curvature, including with myopia and myopic astigmatism. Usually, such correction is applied in young patients of working age that acquires special social significance and requires the use of the most accurate and safe technologies, which would guarantee the achievement of a rapid effect with the shortest period of rehabilitation. The results of surgical treatment of 60 patients (103 eyes) with myopia of various degrees and myopic astigmatism were analyzed. Among patients, there were 28 men (41 %) and 32 women (59 %) aged 18 to 47 (mean of 25.0 ± 2.5) years. They were divided into 2 groups. The first group consisted of 29 people (50 eyes) who underwent vision correction by laser-assisted in situ keratomileusis (LASIK). All patients underwent standard ophthalmological examinations (visometry, autorefractometry, biomicroscopy, direct ophthalmoscopy, tonometry, perimetry) and refractive diagnosis, which included corneal topography with pachymetry (Orbscan, Bausch + Lomb Inc., USA), aberrometry (Zywave, Bausch + Lomb Inc., USA), anterior segment optical coherence tomography (Visante OCT, Carl Zeiss Meditec, Germany) and optical biometry by optical biometer IOLMaster (Carl Zeiss Meditec, Germany). The refractive result achievement was assessed on day 1, as well as 1 month, 6 months and 1 year after surgery. All surgeries were performed on an excimer laser Allegretto WaveLight EX500 (Alcon, USA). One month after excimer laser correction by the LASIK method, the expected result of visual acuity was achieved in 46 eyes (80.7 %), and when using the laser epithelial keratomileusis (LASEK) technique — in 31 eyes (58.5 %) that indicates a longer rehabilitation period. Six months later, the predicted visual acuity without correction in the group where surgery was performed by LASEK was achieved in 46 eyes (86.8 %), while in the group operated by LASIK — in 50 eyes, 100 % (the difference is not reliable, p > 0.05). One year after excimer laser correction, uncorrected visual acuity, regardless of the degree of myopia, was 0.92 ± 0.04 U in the first group at maximum visual acuity with correction in these eyes before surgery 0.86 ± 0.05 U (the difference is not significant, p > 0.05) and 0.74 ± 0.10 U in the second group at the maximum indicators of corrected visual acuity before surgery of 0.92 ± 0.03 U (the difference is significant, p < 0.05). A slightly larger difference in the achieved results of maximum uncorrected visual acuity before surgery when performing excimer laser correction by the LASEK method is explained by the development of subepithelial fibroplasia in 3.77 % of cases, which affected the average end result.
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45

Son, Hyeck-Soo, Grzegorz Łabuz, Ramin Khoramnia, Timur M. Yildirim, Chul Young Choi, Michael C. Knorz, and Gerd U. Auffarth. "Visualization of Forward Light Scatter in Opacified Intraocular Lenses and Straylight Assessment." Diagnostics 11, no. 8 (August 22, 2021): 1512. http://dx.doi.org/10.3390/diagnostics11081512.

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Background: Qualitative visualization of forward light scatter and quantitative straylight measurement of intraocular lenses (IOLs). Methods: We analyzed two calcified IOL-explants, the Euromaxx ALI313Y (Argonoptics GmbH) and the LS-312 MF30 (Oculentis BV), one IOL with artificially induced glistenings (PC-60AD, Hoya), and one control (CT Asphina 409MP, Carl Zeiss Meditec AG) free of any opacification. Analysis included light microscopy, qualitative light scatter visualization using ray propagation imaging technique, and quantitative straylight measurement using C-Quant (Oculus). Results: More light scattering effect—visible as increased light intensity outside the IOL’s main focus—was evident in all opacified IOLs than the control. The highest straylight levels were observed in the Euromaxx (289.71 deg2/sr), which showed extensive granular deposits throughout its optic, followed by the MF30 (78.58 deg2/sr), which only showed opacification in its center. The glistenings-IOL demonstrated numerous microvacuoles within the optic and had straylight levels of 22.6 deg2/sr, while the control showed the lowest straylight levels (1.7 deg2/sr). Conclusions: Ray propagation imaging technique allowed qualitative assessment of off-axis veils of light that result from increased forward light scattering. Straylight was increased in all opacified lenses compared to the clear control lens. The IOL opacifications are significant sources of glare.
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46

de Barros, F. R. O., M. G. Marques, M. D. Goissis, M. A. Peres, M. P. Milazzotto, F. S. Maria, M. E. O. A. Assumpção, and J. A. Visintin. "243 EFFECT OF OOCYTE RECOVERY TECHNIQUES ON IN VITRO MATURATION OF SWINE OOCYTES." Reproduction, Fertility and Development 21, no. 1 (2009): 219. http://dx.doi.org/10.1071/rdv21n1ab243.

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The aim of this study was to compare 2 different techniques to obtain swine oocytes from abattoir ovaries. Ovaries were washed in saline at 35°C and submitted to slashing or aspiration, simultaneously. For the slashing group, ovaries were held with a hemostat inside a beaker containing 35 mL of HEPES-buffered Tyrode’s media (HbT) and follicles (2–6 mm) were incised with a scalpel. For every 5 slashed ovaries, HbT-containing follicular fluid was transferred to 50-mL centrifuge tubes. For the aspiration group, follicles (2–6 mm) were aspirated using an 18-gauge needle and a 5-mL syringe. The follicular fluid of each ovary was transferred to a 50-mL centrifuge tube. Tubes from both techniques were placed in a water bath at 35°C for 15 min to allow settling of the cumulus–oocyte complexes (COC). The supernatant was removed and the sediment was resuspended in HbT and placed in water bath at 35°C for an additional 15 min. The sediment was resuspended in 15 mL of HbT and COC were recovered under stereomicroscopy. Oocytes were in vitro matured for 44 h in TCM-199 added with 10% porcine follicular fluid (PFF) and hormones (LH and FSH) at 38.5°C, 5% CO2 and high humidity. The oocyte recovery rate of each technique was determined by the ratio between the number of COC and ovaries used. To verify nuclear maturation by epifluorescence microscopy (Zeiss), oocytes were fixed, permeabilized, and incubated in 10 μg mL–1 of RNAse for 30 min and in 10 μg mL–1 of propidium iodide for 10 min. Heat shock protein 70 (HSP70) content was assessed as described in Kawarsky and King (2001 Zygote 9(3), 39–50) to verify the metabolic stress. Data were analyzed by ANOVA and Tukey’s test using the software Statistica for Windows. A level of 5% was considered significant in all assessments. The oocyte recovery rate (COC/ovary) was higher for the slashing group (2.665 ± 0.38) compared with the aspiration group (1.762 ± 0.15). The percentage of oocytes that reached the germinative vesicle (GV) stage (h 0 of maturation) did not differ between groups (100 ± 0 and 86.66 ± 13.36, slashing and aspiration group, respectively). The same was observed for the percentage of oocytes that reached the metaphase II stage (MII, after 44 of maturation; 79.99 ± 9.74 and 96.00 ± 4.00, slashing and aspiration group, respectively). Moreover, no difference at pixel quantification of HSP70 was observed between groups (256.50 ± 42.42 and 238.61 ± 71.18, slashing and aspiration group, respectively). In conclusion, the slashing procedure provided a better oocyte recovery rate compared with the aspiration of ovaries. This technique does not affect nuclear maturation, because no differences were observed regarding the percentage of oocytes that reached the GV and MII stages. In addition, it does not affect HSP70 content, suggesting that the slashing of ovaries does not increase the basal stress of oocytes in an in vitro-maturation system.
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47

Macauley, Chandra, Martina Heller, Alexander Rausch, Frank Kümmel, and Peter Felfer. "A versatile cryo-transfer system, connecting cryogenic focused ion beam sample preparation to atom probe microscopy." PLOS ONE 16, no. 1 (January 19, 2021): e0245555. http://dx.doi.org/10.1371/journal.pone.0245555.

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Atom probe tomography (APT) is a powerful technique to obtain 3D chemical and structural information, however the ‘standard’ atom probe experimental workflow involves transfer of specimens at ambient conditions. The ability to transfer air- or thermally-sensitive samples between instruments while maintaining environmental control is critical to prevent chemical or morphological changes prior to analysis for a variety of interesting sample materials. In this article, we describe a versatile transfer system that enables cryogenic- or room-temperature transfer of specimens in vacuum or atmospheric conditions between sample preparation stations, a focused ion beam system (Zeiss Crossbeam 540) and a widely used commercial atom probe system (CAMECA LEAP 4000X HR). As an example for the use of this transfer system, we present atom probe data of gallium- (Ga)-free grain boundaries in an aluminum (Al) alloy specimen prepared with a Ga-based FIB.
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48

Yoo, Hyokyung, and Byung Jun Kim. "History and Recent Advances in Microsurgery." Archives of Hand and Microsurgery 26, no. 3 (September 1, 2021): 174–83. http://dx.doi.org/10.12790/ahm.21.0097.

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Since the late 19th century, microsurgery has achieved many miracles in history of surgery. With the development of microsurgical instruments and techniques, especially the first operating microscope invented by Carl Zeiss in 1953, the limitations steadily decreased and finally reached a limitless level of today’s supermicrosurgery. The chronological history of microsurgery can be divided into four periods: the beginning period of the late 19th to early 20th century when the essential microsurgical tools and concepts were established; the successful replantation of amputated extremities in the 1960s; the development of various kinds of flap in the 1980s; and the fully-matured period of today. This article reviews the milestones in the history of microsurgery, evaluates the recent advances, as well as microsurgery in Korea.
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49

INDRIE, LILIANA, LUCIA CAPABLANCA FRANCES, EMRE ERDEN, MUSA KILIC, DORİNA CAMELİA ILIES, VASILE GRAMA, BAHODIRHON SAFAROV, and ZLATIN ZLATEV. "Old maps and the effectiveness of chitosan as antimicrobial agent." Industria Textila 73, no. 04 (August 31, 2022): 420–25. http://dx.doi.org/10.35530/it.073.04.202156.

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In the case of tangible cultural heritage items made of natural fibres, biodegradation due to microorganisms can lead over time to undesirable deterioration, including physical, mechanical and chemical damage as well as aesthetic alteration of materials. In this study, the antifungal activity tests were performed on 3 old maps (on silk, on canvas and on paper) using the AATCC 30-2004 test method. Map samples were immersed in a chitosan solution (10 g/l) and evaluated using Scanning Electron Microscopy (SEM) with a Field Emission Scanning Electron Microscope (ULTRA 55, ZEISS). The process showed that, due to its antimicrobial effect, chitosan treatment is effective for removing external agents and microorganisms present on fibre surfaces. The technique is simple, efficient and the results indicated that chitosan can be transformed into a very good and cheap antimicrobial solution for the conservation and preservation of heritage objects.
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50

CHAI, JINGWEN, and QING SONG. "MULTISPECTRAL CONCURRENT DETECTION OF MULTIPLE PROTEINS." Nano LIFE 02, no. 03 (September 2012): 1241004. http://dx.doi.org/10.1142/s1793984412410048.

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Proteins constitutively function within networks. Concurrent detection of multiple proteins is crucial to clinical diagnoses and multidimensional drug profiling. Fluorescence microscopy is capable of multicolor imaging, and has the capability to quantify essentially any physiological changes that occur at the single-cell level and in the context of live single cells, and thus provides an alternative to flow cytometry for multiplexed live single-cell assay. The staining of cells with multiple labels is still a technical challenge while multiplexed assays are complicated by spectral emission overlaps and measurement errors. In this study, we applied emission fingerprinting technique provided by Zeiss LSM 510 META detector, and achieved concurrent detection of ten proteins expressed on the same endothelial cell sample. This approach can be further applied to real-time measurement of multiple proteins expressed on live single cell surface, and therefore will enable a novel approach of multiplexed live single cell detection.
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