[Applying healthcare failure mode and effect analysis to improve the surgical specimen transportation process and rejection rate].

PubMed

Hu, Pao-Hsueh; Hu, Hsiao-Chen; Huang, Hui-Ju; Chao, Hui-Lin; Lei, Ei-Fang

2014-04-01

Because surgical pathology specimens are crucial to the diagnosis and treatment of disease, it is critical that they be collected and transported safely and securely. Due to recent near-miss events in our department, we used the healthcare failure model and effect analysis to identify 14 potential perils in the specimen collection and transportation process. Improvement and prevention strategies were developed accordingly to improve quality of care. Using health care failure mode and effect analysis (HFMEA) may improve the surgical specimen transportation process and reduce the rate of surgical specimen rejection. Rectify standard operating procedures for surgical pathology specimen collection and transportation. Create educational videos and posters. Rectify methods of specimen verification. Organize and create an online and instantaneous management system for specimen tracking and specimen rejection. Implementation of the new surgical specimen transportation process effectively eliminated the 14 identified potential perils. In addition, the specimen rejection fell from 0.86% to 0.03%. This project was applied to improve the specimen transportation process, enhance interdisciplinary cooperation, and improve the patient-centered healthcare system. The creation and implementation of an online information system significantly facilitates specimen tracking, hospital cost reductions, and patient safety improvements. The success in our department is currently being replicated across all departments in our hospital that transport specimens. Our experience and strategy may be applied to inter-hospital specimen transportation in the future.

Preparation of reconstituted Charpy V-notch impact specimens for generating pressure vessel steel fracture toughness data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perrin, J.S.; Fromm, E.O.; Server, W.L.

1982-01-01

The arc stud welding process has been adapted for use in producing reconstituted Charpy V-notch impact specimens. In this process, each half of a tested and fractured Charpy specimen is used as the central region of a reconstituted specimen. End tabs are joined to one half of a fractured specimen by a specially designed stud welding apparatus. SA533B-1 and SA508-2 unirradiated and irradiated pressure vessel steel specimens have been produced. Both conventional and precracked reconstituted specimen data have been produced. Both types of data have been shown to be in excellent agreement with original specimen data. The arc stud weldingmore » process can therefore be used to increase the amount of data obtainable from a limited number of specimens or to obtain Charpy data when full size specimens cannot otherwise be obtained.« less

Automated Plasma Spray (APS) process feasibility study

NASA Technical Reports Server (NTRS)

Fetheroff, C. W.; Derkacs, T.; Matay, I. M.

1981-01-01

An automated plasma spray (APS) process was developed to apply two layer (NiCrAlY and ZrO2-12Y2O3) thermal barrier coatings to aircraft and stationary gas turbine engine blade airfoils. The APS process hardware consists of four subsystems: a mechanical positioning subsystem incorporating two interlaced six degree of freedom assemblies (one for coating deposition and one for coating thickness monitoring); a noncoherent optical metrology subsystem (for in process gaging of the coating thickness buildup at specified points on the specimen); a microprocessor based adaptive system controller (to achieve the desired overall thickness profile on the specimen); and commerical plasma spray equipment. Over fifty JT9D first stage aircraft turbine blade specimens, ten W501B utility turbine blade specimens and dozens of cylindrical specimens were coated with the APS process in preliminary checkout and evaluation studies. The best of the preliminary turbine blade specimens achieved an overall coating thickness uniformity of 53 micrometers (2.1 mils), much better than is achievable manually. Comparative evaluations of coating thickness uniformity for manually sprayed and APS coated specimens were performed. One of the preliminary turbine blade evaluation specimens was subjected to a torch test and metallographic evaluation. Some cylindrical specimens coated with the APS process survived up to 2000 cycles in subsequent burner rig testing.

Experimental development of processes to produce homogenized alloys of immiscible metals, phase 3

NASA Technical Reports Server (NTRS)

Reger, J. L.

1976-01-01

An experimental drop tower package was designed and built for use in a drop tower. This effort consisted of a thermal analysis, container/heater fabrication, and assembly of an expulsion device for rapid quenching of heated specimens during low gravity conditions. Six gallium bismuth specimens with compositions in the immiscibility region (50 a/o of each element) were processed in the experimental package: four during low gravity conditions and two under a one gravity environment. One of the one gravity processed specimens did not have telemetry data and was subsequently deleted for analysis since the processing conditions were not known. Metallurgical, Hall effect, resistivity, and superconductivity examinations were performed on the five specimens. Examination of the specimens showed that the gallium was dispersed in the bismuth. The low gravity processed specimens showed a relatively uniform distribution of gallium, with particle sizes of 1 micrometer or less, in contrast to the one gravity control specimen. Comparison of the cooling rates of the dropped specimens versus microstructure indicated that low cooling rates are more desirable.

Research study on materials processing in space, M566 experiment

NASA Technical Reports Server (NTRS)

Douglas, F. C.; Galasso, F. S.

1974-01-01

Specimens of the aluminum-33 wt% copper eutectic partially melted and resolidified in the low effective gravity of the orbiting Skylab were examined and characterized with respect to microstructural defects and thermal conductivity values. The results obtained were compared with similar evaluations of ground-based simulation melt-resolidification experiments and as-prepared unidirectionally solidified specimens. Thermal conductivity data and electrical resistivity data at temperatures from 25 C to 400 C did not show significant differences between ground and space processed specimens. A methology of evaluating the defects in the Al-Al2Cu structure was implemented. A specimen from Skylab 3 showed signs of instability in growth and several grains were found in the ingot. The specimen from Skylab 4 did not show such marked instability in growth and was found to contain fewer defects than the ground-processed specimens. This agrees with data from Georgia Institute of Technology which showed that there were fewer defects in both their Skylab 3 and 4 specimens than in ground processed specimens.

Integration of Value Stream Map and Healthcare Failure Mode and Effect Analysis into Six Sigma Methodology to Improve Process of Surgical Specimen Handling.

PubMed

Hung, Sheng-Hui; Wang, Pa-Chun; Lin, Hung-Chun; Chen, Hung-Ying; Su, Chao-Ton

2015-01-01

Specimen handling is a critical patient safety issue. Problematic handling process, such as misidentification (of patients, surgical site, and specimen counts), specimen loss, or improper specimen preparation can lead to serious patient harms and lawsuits. Value stream map (VSM) is a tool used to find out non-value-added works, enhance the quality, and reduce the cost of the studied process. On the other hand, healthcare failure mode and effect analysis (HFMEA) is now frequently employed to avoid possible medication errors in healthcare process. Both of them have a goal similar to Six Sigma methodology for process improvement. This study proposes a model that integrates VSM and HFMEA into the framework, which mainly consists of define, measure, analyze, improve, and control (DMAIC), of Six Sigma. A Six Sigma project for improving the process of surgical specimen handling in a hospital was conducted to demonstrate the effectiveness of the proposed model.

Dried blood spot specimen quality and validation of a new pre-analytical processing method for qualitative HIV-1 PCR, KwaZulu-Natal, South Africa

PubMed Central

Parboosing, Raveen; Siyaca, Ntombizandile; Moodley, Pravikrishnen

2016-01-01

Background Poor quality dried blood spot (DBS) specimens are usually rejected by virology laboratories, affecting early infant diagnosis of HIV. The practice of combining two incompletely-filled DBS in one specimen preparation tube during pre-analytical specimen processing (i.e., the two-spot method) has been implemented to reduce the number of specimens being rejected for insufficient volume. Objectives This study analysed laboratory data to describe the quality of DBS specimens and the use of the two-spot method over a one-year period, then validated the two-spot method against the standard (one-spot) method. Methods Data on HIV-1 PCR test requests submitted in 2014 to the Department of Virology at Inkosi Albert Luthuli Central Hospital in KwaZulu-Natal province, South Africa were analysed to describe reasons for specimen rejection, as well as results of the two-spot method. The accuracy, lower limit of detection and precision of the two-spot method were assessed. Results Of the 88 481 specimens received, 3.7% were rejected for pre-analytical problems. Of those, 48.9% were rejected as a result of insufficient specimen volume. Two health facilities had significantly more specimen rejections than other facilities. The two-spot method prevented 10 504 specimen rejections. The Pearson correlation coefficient comparing the standard to the two-spot method was 0.997. Conclusions The two-spot method was comparable with the standard method of pre-analytical specimen processing. Two health facilities were identified for targeted retraining on specimen quality. The two-spot method of DBS specimen processing can be used as an adjunct to retraining, to reduce the number of specimens rejected and improve linkage to care. PMID:28879108

Dried blood spot specimen quality and validation of a new pre-analytical processing method for qualitative HIV-1 PCR, KwaZulu-Natal, South Africa.

PubMed

Govender, Kerusha; Parboosing, Raveen; Siyaca, Ntombizandile; Moodley, Pravikrishnen

2016-01-01

Poor quality dried blood spot (DBS) specimens are usually rejected by virology laboratories, affecting early infant diagnosis of HIV. The practice of combining two incompletely-filled DBS in one specimen preparation tube during pre-analytical specimen processing (i.e., the two-spot method) has been implemented to reduce the number of specimens being rejected for insufficient volume. This study analysed laboratory data to describe the quality of DBS specimens and the use of the two-spot method over a one-year period, then validated the two-spot method against the standard (one-spot) method. Data on HIV-1 PCR test requests submitted in 2014 to the Department of Virology at Inkosi Albert Luthuli Central Hospital in KwaZulu-Natal province, South Africa were analysed to describe reasons for specimen rejection, as well as results of the two-spot method. The accuracy, lower limit of detection and precision of the two-spot method were assessed. Of the 88 481 specimens received, 3.7% were rejected for pre-analytical problems. Of those, 48.9% were rejected as a result of insufficient specimen volume. Two health facilities had significantly more specimen rejections than other facilities. The two-spot method prevented 10 504 specimen rejections. The Pearson correlation coefficient comparing the standard to the two-spot method was 0.997. The two-spot method was comparable with the standard method of pre-analytical specimen processing. Two health facilities were identified for targeted retraining on specimen quality. The two-spot method of DBS specimen processing can be used as an adjunct to retraining, to reduce the number of specimens rejected and improve linkage to care.

Apparatus and method for magnetically processing a specimen

DOEpatents

Ludtka, Gerard M; Ludtka, Gail M; Wilgen, John B; Kisner, Roger A; Jaramillo, Roger A

2013-09-03

An apparatus for magnetically processing a specimen that couples high field strength magnetic fields with the magnetocaloric effect includes a high field strength magnet capable of generating a magnetic field of at least 1 Tesla and a magnetocaloric insert disposed within a bore of the high field strength magnet. A method for magnetically processing a specimen includes positioning a specimen adjacent to a magnetocaloric insert within a bore of a magnet and applying a high field strength magnetic field of at least 1 Tesla to the specimen and to the magnetocaloric insert. The temperature of the specimen changes during the application of the high field strength magnetic field due to the magnetocaloric effect.

Fabrication of Titanium Bonded Joint Specimens for High Temperature Testing

NASA Technical Reports Server (NTRS)

Smeltzer, Stanley S., III; Kovach, Michael P.; Hudson, Wanda

2005-01-01

Four sets of adhesively bonded, titanium lap-shear coupon specimens were fabricated for ultimate strength testing according to the ASTM D1002 and D3165 standards. Important features of the fabrication methods, processing details, and lap-shear test results are presented for specimens fabricated using a modified bismaleimide adhesive, EA 9673, on titanium. Surface treatment of the titanium was performed using surface abrasion followed by one of two separate chemical etching processes. Although cure cycle requirements are different among most adhesives, a single surface preparation method was sought as the preferred method for conditioning the titanium specimens prior to bonding and curing. A fabrication process using a combination of low-pressure grit-blasting of the titanium surface followed by anodization with a sodium hydroxide solution applied to the D1002 specimen geometry provided the highest lapshear strengths in the study. Additionally, difficulties documented during the fabrication process of the D3165 specimens along with features of the D3165 geometry were identified as factors that contributed to lower lap-shear strength results for the D3165 specimens as compared to the results for the D1002 specimens.

Effect of the Machining Processes on Low Cycle Fatigue Behavior of a Powder Metallurgy Disk

NASA Technical Reports Server (NTRS)

Telesman, J.; Kantzos, P.; Gabb, T. P.; Ghosn, L. J.

2010-01-01

A study has been performed to investigate the effect of various machining processes on fatigue life of configured low cycle fatigue specimens machined out of a NASA developed LSHR P/M nickel based disk alloy. Two types of configured specimen geometries were employed in the study. To evaluate a broach machining processes a double notch geometry was used with both notches machined using broach tooling. EDM machined notched specimens of the same configuration were tested for comparison purposes. Honing finishing process was evaluated by using a center hole specimen geometry. Comparison testing was again done using EDM machined specimens of the same geometry. The effect of these machining processes on the resulting surface roughness, residual stress distribution and microstructural damage were characterized and used in attempt to explain the low cycle fatigue results.

Analysing the influence of FSP process parameters on IGC susceptibility of AA5083 using Sugeno - Fuzzy model

NASA Astrophysics Data System (ADS)

Jayakarthick, C.; Povendhan, A. P.; Vaira Vignesh, R.; Padmanaban, R.

2018-02-01

Aluminium alloy AA5083 was friction stir processed to improve the intergranular corrosion (IGC) resistance. FSP trials were performed by varying the process parameters as per Taguchi’s L18 orthogonal array. IGC resistance of the friction stir processed specimens were found by immersing them in concentrated nitric acid and measuring the mass loss per unit area. Results indicate that dispersion and partial dissolution of secondary phase increased IGC resistance of the friction stir processed specimens. A Sugeno fuzzy model was developed to study the effect of FSP process parameters on the IGC susceptibility of friction stir processed specimens. Tool Rotation Speed, Tool Traverse Speed and Shoulder Diameter have a significant effect on the IGC susceptibility of the friction stir processed specimens.

Assessment of HER2 status in breast cancer biopsies is not affected by accelerated tissue processing.

PubMed

Bulte, Joris P; Halilovic, Altuna; Kalkman, Shona; van Cleef, Patricia H J; van Diest, Paul J; Strobbe, Luc J A; de Wilt, Johannes H W; Bult, Peter

2018-03-01

To establish whether core needle biopsy (CNB) specimens processed with an accelerated processing method with short fixation time can be used to determine accurately the human epidermal growth factor receptor 2 (HER2) status of breast cancer. A consecutive case-series from two high-volume breast clinics was created. We compared routine HER2 immunohistochemistry (IHC) assessment between accelerated processing CNB specimens and routinely processed postoperative excision specimens. Additional amplification-based testing was performed in cases with equivocal results. The formalin fixation time was less than 2 h and between 6 and 72 h, respectively. Fluorescence in-situ hybridisation and multiplex ligation-dependent probe amplification were used for amplification testing. One hundred and forty-four cases were included, 15 of which were HER2-positive on the routinely processed excision specimens. On the CNB specimens, 44 were equivocal on IHC and required an amplification-based test. Correlation between the CNB specimens and the corresponding excision specimens was high for final HER2 status, with an accuracy of 97% and a kappa of 0.85. HER2 status can be determined reliably on CNB specimens with accelerated processing time using standard clinical testing methods. Using this accelerated technology the minimum 6 h of formalin fixation, which current guidelines consider necessary, can be decreased safely. This allows for a complete and expedited histology-based diagnosis of breast lesions in the setting of a one-stop-shop, same-day breast clinic. © 2018 The Authors. Histopathology Published by John Wiley & Sons Ltd.

The use of Optical Character Recognition (OCR) in the digitisation of herbarium specimen labels.

PubMed

Drinkwater, Robyn E; Cubey, Robert W N; Haston, Elspeth M

2014-01-01

At the Royal Botanic Garden Edinburgh (RBGE) the use of Optical Character Recognition (OCR) to aid the digitisation process has been investigated. This was tested using a herbarium specimen digitisation process with two stages of data entry. Records were initially batch-processed to add data extracted from the OCR text prior to being sorted based on Collector and/or Country. Using images of the specimens, a team of six digitisers then added data to the specimen records. To investigate whether the data from OCR aid the digitisation process, they completed a series of trials which compared the efficiency of data entry between sorted and unsorted batches of specimens. A survey was carried out to explore the opinion of the digitisation staff to the different sorting options. In total 7,200 specimens were processed. When compared to an unsorted, random set of specimens, those which were sorted based on data added from the OCR were quicker to digitise. Of the methods tested here, the most successful in terms of efficiency used a protocol which required entering data into a limited set of fields and where the records were filtered by Collector and Country. The survey and subsequent discussions with the digitisation staff highlighted their preference for working with sorted specimens, in which label layout, locations and handwriting are likely to be similar, and so a familiarity with the Collector or Country is rapidly established.

49 CFR 40.63 - What steps does the collector take in the collection process before the employee provides a urine...

Code of Federal Regulations, 2011 CFR

2011-10-01

... collection process before the employee provides a urine specimen? 40.63 Section 40.63 Transportation Office... PROGRAMS Urine Specimen Collections § 40.63 What steps does the collector take in the collection process before the employee provides a urine specimen? As the collector, you must take the following steps before...

49 CFR 40.63 - What steps does the collector take in the collection process before the employee provides a urine...

Code of Federal Regulations, 2013 CFR

2013-10-01

... collection process before the employee provides a urine specimen? 40.63 Section 40.63 Transportation Office... PROGRAMS Urine Specimen Collections § 40.63 What steps does the collector take in the collection process before the employee provides a urine specimen? As the collector, you must take the following steps before...

49 CFR 40.63 - What steps does the collector take in the collection process before the employee provides a urine...

Code of Federal Regulations, 2014 CFR

2014-10-01

... collection process before the employee provides a urine specimen? 40.63 Section 40.63 Transportation Office... PROGRAMS Urine Specimen Collections § 40.63 What steps does the collector take in the collection process before the employee provides a urine specimen? As the collector, you must take the following steps before...

49 CFR 40.63 - What steps does the collector take in the collection process before the employee provides a urine...

Code of Federal Regulations, 2012 CFR

2012-10-01

... collection process before the employee provides a urine specimen? 40.63 Section 40.63 Transportation Office... PROGRAMS Urine Specimen Collections § 40.63 What steps does the collector take in the collection process before the employee provides a urine specimen? As the collector, you must take the following steps before...

Influence of Water Content on Mechanical Properties of Rock in Both Saturation and Drying Processes

NASA Astrophysics Data System (ADS)

Zhou, Zilong; Cai, Xin; Cao, Wenzhuo; Li, Xibing; Xiong, Cheng

2016-08-01

Water content has a pronounced influence on the properties of rock materials, which is responsible for many rock engineering hazards, such as landslides and karst collapse. Meanwhile, water injection is also used for the prevention of some engineering disasters like rock-bursts. To comprehensively investigate the effect of water content on mechanical properties of rocks, laboratory tests were carried out on sandstone specimens with different water contents in both saturation and drying processes. The Nuclear Magnetic Resonance technique was applied to study the water distribution in specimens with variation of water contents. The servo-controlled rock mechanics testing machine and Split Hopkinson Pressure Bar technique were used to conduct both compressive and tensile tests on sandstone specimens with different water contents. From the laboratory tests, reductions of the compressive and tensile strength of sandstone under static and dynamic states in different saturation processes were observed. In the drying process, all of the saturated specimens could basically regain their mechanical properties and recover its strength as in the dry state. However, for partially saturated specimens in the saturation and drying processes, the tensile strength of specimens with the same water content was different, which could be related to different water distributions in specimens.

Static and fatigue interlaminar tensile characterization of laminated composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koudela, K.L.; Strait, L.H.; Caiazzo, A.A.

1997-12-31

Spool and curved-beam specimens were evaluated to determine the viability of using either one or both of these configurations to characterize the static and fatigue interlaminar tensile behavior of carbon/epoxy laminates. Unidirectional curved-beam and quasi-isotropic spool specimens were fabricated, nondestructively inspected, and statically tested to failure. Tension-tension fatigue tests were conducted at 10 Hz and an R-ratio ({sigma}{sub min}/{sigma}{sub max}) equal to 0.1 for each specimen configuration. The interlaminar tensile strength of the spool specimen was 12% larger than the strength obtained using curved-beam specimens. In addition, data scatter associated with spool specimens was significantly less than the scatter associatedmore » with curved-beam specimens. The difference in data scatter was attributed to the influence of the fabrication process on the quality of the laminates tested. The fatigue limit at 0{sup 7} cycles for both specimen types was shown to be at least 40% of the average interlaminar tensile strength. Based on the results of this study, it was concluded that either the spool or the curved-beam specimens can be used to characterize the interlaminar tensile static and fatigue behavior of carbon/epoxy laminates. However, to obtain the most representative results, the test specimen configuration should be selected so that the specimen fabrication process closely simulates the actual component fabrication process.« less

Experimental studies the evolution of stress-strain state in structured rock specimens under uniaxial loading

NASA Astrophysics Data System (ADS)

Oparin, Viktor; Tsoy, Pavel; Usoltseva, Olga; Semenov, Vladimir

2014-05-01

The aim of this study was to analyze distribution and development of stress-stress state in structured rock specimens subject to uniaxial loading to failure. Specific attention was paid to possible oscillating motion of structural elements of the rock specimens under constraints (pre-set stresses at the boundaries of the specimens) and the kinetic energy fractals. The detailed studies into the micro-level stress-strain state distribution and propagation over acting faces of rock specimens subject to uniaxial loading until failure, using automated digital speckle photography analyzer ALMEC-tv, have shown that: • under uniaxial stiff loading of prismatic sandstone, marble and sylvinite specimens on the Instron-8802 servohydraulic testing machine at the mobile grip displacement rate 0.02-0.2 mm/min, at a certain level of stressing, low-frequency micro-deformation processes originate in the specimens due to slow (quasi-static) force; • the amplitude of that deformation-wave processes greatly depends on the micro-loading stage: — at the elastic deformation stage, under the specimen stress lower than half ultimate strength of the specimen, there are no oscillations of microstrains; —at the nonlinearly elastic deformation stage, under stress varied from 0.5 to 1 ultimate strength of the specimens, the amplitudes of microstrains grow, including the descending stage 3; the oscillation frequency f=0.5-4 Hz; —at the residual strength stage, the amplitudes of the microstrains drop abruptly (3-5 times) as against stages 2 and 3; • in the elements of the scanned specimen surface in the region with the incipient crack, the microstrain rate amplitudes are a few times higher than in the undamged surface region of the same specimen. Sometimes, deformation rate greatly grows with increase in the load. The authors have used the energy scanning function of the deformation-wave processes in processing experimental speckle-photography data on the surface of the test specimen subject to loading until failure.

Patient safety in the clinical laboratory: a longitudinal analysis of specimen identification errors.

PubMed

Wagar, Elizabeth A; Tamashiro, Lorraine; Yasin, Bushra; Hilborne, Lee; Bruckner, David A

2006-11-01

Patient safety is an increasingly visible and important mission for clinical laboratories. Attention to improving processes related to patient identification and specimen labeling is being paid by accreditation and regulatory organizations because errors in these areas that jeopardize patient safety are common and avoidable through improvement in the total testing process. To assess patient identification and specimen labeling improvement after multiple implementation projects using longitudinal statistical tools. Specimen errors were categorized by a multidisciplinary health care team. Patient identification errors were grouped into 3 categories: (1) specimen/requisition mismatch, (2) unlabeled specimens, and (3) mislabeled specimens. Specimens with these types of identification errors were compared preimplementation and postimplementation for 3 patient safety projects: (1) reorganization of phlebotomy (4 months); (2) introduction of an electronic event reporting system (10 months); and (3) activation of an automated processing system (14 months) for a 24-month period, using trend analysis and Student t test statistics. Of 16,632 total specimen errors, mislabeled specimens, requisition mismatches, and unlabeled specimens represented 1.0%, 6.3%, and 4.6% of errors, respectively. Student t test showed a significant decrease in the most serious error, mislabeled specimens (P < .001) when compared to before implementation of the 3 patient safety projects. Trend analysis demonstrated decreases in all 3 error types for 26 months. Applying performance-improvement strategies that focus longitudinally on specimen labeling errors can significantly reduce errors, therefore improving patient safety. This is an important area in which laboratory professionals, working in interdisciplinary teams, can improve safety and outcomes of care.

Apparatus and method for materials processing utilizing a rotating magnetic field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muralidharan, Govindarajan; Angelini, Joseph A.; Murphy, Bart L.

An apparatus for materials processing utilizing a rotating magnetic field comprises a platform for supporting a specimen, and a plurality of magnets underlying the platform. The plurality of magnets are configured for rotation about an axis of rotation intersecting the platform. A heat source is disposed above the platform for heating the specimen during the rotation of the plurality of magnets. A method for materials processing utilizing a rotating magnetic field comprises providing a specimen on a platform overlying a plurality of magnets; rotating the plurality of magnets about an axis of rotation intersecting the platform, thereby applying a rotatingmore » magnetic field to the specimen; and, while rotating the plurality of magnets, heating the specimen to a desired temperature.« less

The use of Optical Character Recognition (OCR) in the digitisation of herbarium specimen labels

PubMed Central

Drinkwater, Robyn E.; Cubey, Robert W. N.; Haston, Elspeth M.

2014-01-01

Abstract At the Royal Botanic Garden Edinburgh (RBGE) the use of Optical Character Recognition (OCR) to aid the digitisation process has been investigated. This was tested using a herbarium specimen digitisation process with two stages of data entry. Records were initially batch-processed to add data extracted from the OCR text prior to being sorted based on Collector and/or Country. Using images of the specimens, a team of six digitisers then added data to the specimen records. To investigate whether the data from OCR aid the digitisation process, they completed a series of trials which compared the efficiency of data entry between sorted and unsorted batches of specimens. A survey was carried out to explore the opinion of the digitisation staff to the different sorting options. In total 7,200 specimens were processed. When compared to an unsorted, random set of specimens, those which were sorted based on data added from the OCR were quicker to digitise. Of the methods tested here, the most successful in terms of efficiency used a protocol which required entering data into a limited set of fields and where the records were filtered by Collector and Country. The survey and subsequent discussions with the digitisation staff highlighted their preference for working with sorted specimens, in which label layout, locations and handwriting are likely to be similar, and so a familiarity with the Collector or Country is rapidly established. PMID:25009435

Surgical Specimen Management: A Descriptive Study of 648 Adverse Events and Near Misses.

PubMed

Steelman, Victoria M; Williams, Tamara L; Szekendi, Marilyn K; Halverson, Amy L; Dintzis, Suzanne M; Pavkovic, Stephen

2016-12-01

- Surgical specimen adverse events can lead to delays in treatment or diagnosis, misdiagnosis, reoperation, inappropriate treatment, and anxiety or serious patient harm. - To describe the types and frequency of event reports associated with the management of surgical specimens, the contributing factors, and the level of harm associated with these events. - A retrospective review was undertaken of surgical specimen adverse events and near misses voluntarily reported in the University HealthSystem Consortium Safety Intelligence Patient Safety Organization database by more than 50 health care facilities during a 3-year period (2011-2013). Event reports that involved surgical specimen management were reviewed for patients undergoing surgery during which tissue or fluid was sent to the pathology department. - Six hundred forty-eight surgical specimen events were reported in all stages of the specimen management process, with the most common events reported during the prelaboratory phase and, specifically, with specimen labeling, collection/preservation, and transport. The most common contributing factors were failures in handoff communication, staff inattention, knowledge deficit, and environmental issues. Eight percent of the events (52 of 648) resulted in either the need for additional treatment or temporary or permanent harm to the patient. - All phases of specimen handling and processing are vulnerable to errors. These results provide a starting point for health care organizations to conduct proactive risk analyses of specimen handling procedures and to design safer processes. Particular attention should be paid to effective communication and handoffs, consistent processes across care areas, and staff training. In addition, organizations should consider the use of technology-based identification and tracking systems.

Rapid identification of pathogens directly from blood culture bottles by Bruker matrix-assisted laser desorption laser ionization-time of flight mass spectrometry versus routine methods.

PubMed

Jamal, Wafaa; Saleem, Rola; Rotimi, Vincent O

2013-08-01

The use of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for identification of microorganisms directly from blood culture is an exciting dimension to the microbiologists. We evaluated the performance of Bruker SepsiTyper kit™ (STK) for direct identification of bacteria from positive blood culture. This was done in parallel with conventional methods. Nonrepetitive positive blood cultures from 160 consecutive patients were prospectively evaluated by both methods. Of 160 positive blood cultures, the STK identified 114 (75.6%) isolates and routine conventional method 150 (93%). Thirty-six isolates were misidentified or not identified by the kit. Of these, 5 had score of >2.000 and 31 had an unreliable low score of <1.7. Four of 8 yeasts were identified correctly. The average turnaround time using the STK was 35 min, including extraction steps and 30:12 to 36:12 h with routine method. The STK holds promise for timely management of bacteremic patients. Copyright © 2013 Elsevier Inc. All rights reserved.

Effect of Quenching Process on Microstructures and Mechanical Properties of Fe-0.9Mn-0.5Cr-2.4Ni-0.5Mo-C Steel

NASA Astrophysics Data System (ADS)

Chen, Jie; Li, Changsheng; Jin, Xin; Chen, Liqing; Fang, Lei

2018-03-01

To develop an appropriate quenching process to produce Fe-0.9Mn-0.5Cr-2.4Ni-0.5Mo-C steel, the microstructures and mechanical properties of this steel were investigated under the direct quenching and tempering (DQT) and the direct quenching, reheated quenching and tempering (DQQT) heat treatment processes. The microstructure of the DQQT specimen was basically tempered sorbite with spherical precipitates, while quite a bit of tempered martensite was in the DQT specimen with dispersive nanoscaled precipitates. The yield strengths of the DQT and DQQT specimens were 1154 and 955 MPa, respectively. The yield strength of the DQT specimen was higher than that of the DQQT specimen because of its finer grain size, higher density of dislocations and dispersed precipitates. The DQQT specimen had spherical precipitates, which hindered the propagation of the crack. Moreover, the high-angle grain boundaries in the DQQT specimen took a higher proportion. Therefore, the Charpy impact values of DQT and DQQT specimens at - 60 °C were 38 and 75 J, respectively. Consequently, the mechanical properties of the Fe-0.9Mn-0.5Cr-2.4Ni-0.5Mo-C steel, which met the standard of 1000 MPa grade steel plate for hydropower station, were acquired by the DQQT process.

Closeout of JOYO-1 Specimen Fabrication Efforts

DOE Office of Scientific and Technical Information (OSTI.GOV)

ME Petrichek; JL Bump; RF Luther

2005-10-31

Fabrication was well under way for the JOYO biaxial creep and tensile specimens when the NR Space program was canceled. Tubes of FS-85, ASTAR-811C, and T-111 for biaxial creep specimens had been drawn at True Tube (Paso Robles, CA), while tubes of Mo-47.5 Re were being drawn at Rhenium Alloys (Cleveland, OH). The Mo-47.5 Re tubes are now approximately 95% complete. Their fabrication and the quantities produced will be documented at a later date. End cap material for FS-85, ASTAR-811C, and T-111 had been swaged at Pittsburgh Materials Technology, Inc. (PMTI) (Large, PA) and machined at Vangura (Clairton, PA). Cuttingmore » of tubes, pickling, annealing, and laser engraving were in process at PMTI. Several biaxial creep specimen sets of FS-85, ASTAR-811C, and T-111 had already been sent to Pacific Northwest National Laboratory (PNNL) for weld development. In addition, tensile specimens of FS-85, ASTAR-811C, T-111, and Mo-47.5 Re had been machined at Kin-Tech (North Huntington, PA). Actual machining of the other specimen types had not been initiated. Flowcharts 1-3 detail the major processing steps each piece of material has experienced. A more detailed description of processing will be provided in a separate document [B-MT(SRME)-51]. Table 1 lists the in-process materials and finished specimens. Also included are current metallurgical condition of these materials and specimens. The available chemical analyses for these alloys at various points in the process are provided in Table 2.« less

Tensile strength of various nylon PA6 specimen modes

NASA Astrophysics Data System (ADS)

Raz, Karel; Zahalka, Martin

2017-05-01

This article explores the influence of production technique on the strength of nylon parts. Identical specimens were manufactured by various techniques. The material of specimens was nylon PA6. 3D printing and injection molding were used, with various orientations of printed layers, and various orientations of specimens in the working space of the 3D printer. The variants are described in detail. A special mold was used for the injection molding process in order to make specimens with and without a weld line. The effect of this weld line was evaluated. All specimens were tested using the standard tensile test configuration. The strength was compared. It was found that the same plastic material has very different mechanical properties depending on the production process.

Nonlinear fracture of concrete and ceramics

NASA Technical Reports Server (NTRS)

Kobayashi, Albert S.; Du, Jia-Ji; Hawkins, Niel M.; Bradt, Richard C.

1989-01-01

The nonlinear fracture process zones in an impacted unnotched concrete bend specimen, a prenotched ceramic bend specimen, and an unnotched ceramic/ceramic composite bend specimen were estimated through hybrid experimental numerical analysis. Aggregate bridging in concrete, particulate bridging in ceramics, and fiber bridging in ceramic/ceramic composite are modeled by Barenblatt-type cohesive zones which are incorporated into the finite-element models of the bend specimens. Both generation and propagation analyses are used to estimate the distribution of crack closure stresses in the nonlinear fracture process zones. The finite-element models are then used to simulate fracture tests consisting of rapid crack propagation in an impacted concrete bend specimen, and stable crack growth and strain softening in a ceramic and ceramic/ceramic composite bend specimens.

Microwave processing of a dental ceramic used in computer-aided design/computer-aided manufacturing.

PubMed

Pendola, Martin; Saha, Subrata

2015-01-01

Because of their favorable mechanical properties and natural esthetics, ceramics are widely used in restorative dentistry. The conventional ceramic sintering process required for their use is usually slow, however, and the equipment has an elevated energy consumption. Sintering processes that use microwaves have several advantages compared to regular sintering: shorter processing times, lower energy consumption, and the capacity for volumetric heating. The objective of this study was to test the mechanical properties of a dental ceramic used in computer-aided design/computer-aided manufacturing (CAD/CAM) after the specimens were processed with microwave hybrid sintering. Density, hardness, and bending strength were measured. When ceramic specimens were sintered with microwaves, the processing times were reduced and protocols were simplified. Hardness was improved almost 20% compared to regular sintering, and flexural strength measurements suggested that specimens were approximately 50% stronger than specimens sintered in a conventional system. Microwave hybrid sintering may preserve or improve the mechanical properties of dental ceramics designed for CAD/CAM processing systems, reducing processing and waiting times.

Microscope and method of use

DOEpatents

Bongianni, Wayne L.

1984-01-01

A method and apparatus for electronically focusing and electronically scanning microscopic specimens are given. In the invention, visual images of even moving, living, opaque specimens can be acoustically obtained and viewed with virtually no time needed for processing (i.e., real time processing is used). And planar samples are not required. The specimens (if planar) need not be moved during scanning, although it will be desirable and possible to move or rotate nonplanar specimens (e.g., laser fusion targets) against the lens of the apparatus. No coupling fluid is needed, so specimens need not be wetted. A phase acoustic microscope is also made from the basic microscope components together with electronic mixers.

Microscope and method of use

DOEpatents

Bongianni, W.L.

1984-04-17

A method and apparatus for electronically focusing and electronically scanning microscopic specimens are given. In the invention, visual images of even moving, living, opaque specimens can be acoustically obtained and viewed with virtually no time needed for processing (i.e., real time processing is used). And planar samples are not required. The specimens (if planar) need not be moved during scanning, although it will be desirable and possible to move or rotate nonplanar specimens (e.g., laser fusion targets) against the lens of the apparatus. No coupling fluid is needed, so specimens need not be wetted. A phase acoustic microscope is also made from the basic microscope components together with electronic mixers. 7 figs.

Blocking contacts for N-type cadmium zinc telluride

NASA Technical Reports Server (NTRS)

Stahle, Carl M. (Inventor); Parker, Bradford H. (Inventor); Babu, Sachidananda R. (Inventor)

2012-01-01

A process for applying blocking contacts on an n-type CdZnTe specimen includes cleaning the CdZnTe specimen; etching the CdZnTe specimen; chemically surface treating the CdZnTe specimen; and depositing blocking metal on at least one of a cathode surface and an anode surface of the CdZnTe specimen.

Refining the 'cucumber' technique for laryngeal biopsy.

PubMed

Robertson, S; Cooper, L; McPhaden, A; MacKenzie, K

2011-06-01

To refine the case selection process for the 'cucumber' mounting system for laryngeal biopsies. We conducted a retrospective audit of cucumber technique specimens taken between January 2002 and December 2008. We analysed the clinical indications for biopsy and the pathological diagnosis, for each specimen, in order to inform our case selection process. The cucumber technique was used for 125 laryngeal specimens. 60 specimens were taken for diagnostic sampling, 46 were taken during endoscopic laser resection, and 19 for overtly benign pathology. The cucumber technique was most useful for the interpretation of margins in endoscopic laser resection specimens. The cucumber technique is most useful for endoscopic resection cases in which tumour, dysplasia or suspicious lesions have been excised. Detailed information on resection margins is invaluable during multidisciplinary team discussions on patient management. Detailed photography of mounted specimens enables both laryngologist and pathologist to orientate and interpret specimens accurately.

Compressive behavior of laminated neoprene bridge bearing pads under thermal aging condition

NASA Astrophysics Data System (ADS)

Jun, Xie; Zhang, Yannian; Shan, Chunhong

2017-10-01

The present study was conducted to obtain a better understanding of the variation rule of mechanical properties of laminated neoprene bridge bearing pads under thermal aging condition using compression tests. A total of 5 specimens were processed in a high-temperature chamber. After that, the specimens were tested subjected to axial load. The parameter mainly considered time of thermal aging processing for specimens. The results of compression tests show that the specimens after thermal aging processing are more probably brittle failure than the standard specimen. Moreover, the exposure of steel plate, cracks and other failure phenomena are more serious than the standard specimen. The compressive capacity, ultimate compressive strength, compressive elastic modulus of the laminated neoprene bridge bearing pads decreased dramatically with the increasing in the aging time of thermal aging processing. The attenuation trends of ultimate compressive strength, compressive elastic modulus of laminated neoprene bridge bearing pads under thermal aging condition accord with power function. The attenuation models are acquired by regressing data of experiment with the least square method. The attenuation models conform to reality well which shows that this model is applicable and has vast prospect in assessing the performance of laminated neoprene bridge bearing pads under thermal aging condition.

Processing of fallopian tube, ovary, and endometrial surgical pathology specimens: A survey of U.S. laboratory practices.

PubMed

Samimi, Goli; Trabert, Britton; Duggan, Máire A; Robinson, Jennifer L; Coa, Kisha I; Waibel, Elizabeth; Garcia, Edna; Minasian, Lori M; Sherman, Mark E

2018-03-01

Many high-grade serous carcinomas initiate in fallopian tubes as serous tubal intraepithelial carcinoma (STIC), a microscopic lesion identified with specimen processing according to the Sectioning and Extensive Examination of the Fimbria protocol (SEE-Fim). Given that the tubal origin of these cancers was recently recognized, we conducted a survey of pathology practices to assess processing protocols that are applied to gynecologic surgical pathology specimens in clinical contexts in which finding STIC might have different implications. We distributed a survey electronically to the American Society for Clinical Pathology list-serve to determine practice patterns and compared results between practice types by chi-square (χ2) tests for categorical variables. Free text comments were qualitatively reviewed. Survey responses were received from 159 laboratories (72 academic, 87 non-academic), which reported diverse specimen volumes and percentage of gynecologic samples. Overall, 74.1% of laboratories reported performing SEE-Fim for risk-reducing surgical specimens (82.5% academic versus 65.7% non-academic, p < 0.05). In specimens from surgery for benign indications in which initial microscopic sections showed an unanticipated suspicious finding, 75.9% of laboratories reported using SEE-Fim to process the remainder of the specimen (94.8% academic versus 76.4% non-academic, p < 0.01), and 84.6% submitted the entire fimbriae. Changes in the theories of pathogenesis of high-grade serous carcinoma have led to implementation of pathology specimen processing protocols that include detailed analysis of the fallopian tubes. These results have implications for interpreting trends in cancer incidence data and considering the feasibility of developing a bank of gynecologic tissues containing STIC or early cancer precursors. Published by Elsevier Inc.

10 CFR 26.5 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... means a group of validity screening tests that were made from the same starting material. ... past 24 hours. Adulterated specimen means a urine specimen that has been altered, as evidenced by test... whole specimen. Analytical run means the process of testing a group of urine specimens for validity or...

10 CFR 26.5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... means a group of validity screening tests that were made from the same starting material. ... past 24 hours. Adulterated specimen means a urine specimen that has been altered, as evidenced by test... whole specimen. Analytical run means the process of testing a group of urine specimens for validity or...

10 CFR 26.5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... means a group of validity screening tests that were made from the same starting material. ... past 24 hours. Adulterated specimen means a urine specimen that has been altered, as evidenced by test... whole specimen. Analytical run means the process of testing a group of urine specimens for validity or...

10 CFR 26.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... means a group of validity screening tests that were made from the same starting material. ... past 24 hours. Adulterated specimen means a urine specimen that has been altered, as evidenced by test... whole specimen. Analytical run means the process of testing a group of urine specimens for validity or...

10 CFR 26.5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... means a group of validity screening tests that were made from the same starting material. ... past 24 hours. Adulterated specimen means a urine specimen that has been altered, as evidenced by test... whole specimen. Analytical run means the process of testing a group of urine specimens for validity or...

Evaluation of the Behavior of Technova Corporation Rod-Stiffened Stitched Compression Specimens

NASA Technical Reports Server (NTRS)

Jegley, Dawn C.

2013-01-01

Under Space Act Agreement 1347 between NASA and Technova Corporation, Technova designed and fabricated two carbon-epoxy crippling specimens and NASA loaded them to failure in axial compression. Each specimen contained a pultruded rod stiffener which was held to the specimen skin with through-the-thickness stitches. One of these specimens was designed to be nominally the same as pultruded rod stitched specimens fabricated by Boeing under previous programs. In the other specimen, the rod was prestressed in a Technova manufacturing process to increase its ability to carrying compressive loading. Experimental results demonstrated that the specimen without prestressing carried approximately the same load as the similar Boeing specimens and that the specimen with prestressing carried significantly more load than the specimen without prestressing.

Uniaxial experimental study of the acoustic emission and deformation behavior of composite rock based on 3D digital image correlation (DIC)

NASA Astrophysics Data System (ADS)

Cheng, Jian-Long; Yang, Sheng-Qi; Chen, Kui; Ma, Dan; Li, Feng-Yuan; Wang, Li-Ming

2017-12-01

In this paper, uniaxial compression tests were carried out on a series of composite rock specimens with different dip angles, which were made from two types of rock-like material with different strength. The acoustic emission technique was used to monitor the acoustic signal characteristics of composite rock specimens during the entire loading process. At the same time, an optical non-contact 3D digital image correlation technique was used to study the evolution of axial strain field and the maximal strain field before and after the peak strength at different stress levels during the loading process. The effect of bedding plane inclination on the deformation and strength during uniaxial loading was analyzed. The methods of solving the elastic constants of hard and weak rock were described. The damage evolution process, deformation and failure mechanism, and failure mode during uniaxial loading were fully determined. The experimental results show that the θ = 0{°}-45{°} specimens had obvious plastic deformation during loading, and the brittleness of the θ = 60{°}-90{°} specimens gradually increased during the loading process. When the anisotropic angle θ increased from 0{°} to 90{°}, the peak strength, peak strain, and apparent elastic modulus all decreased initially and then increased. The failure mode of the composite rock specimen during uniaxial loading can be divided into three categories: tensile fracture across the discontinuities (θ = 0{°}-30{°}), sliding failure along the discontinuities (θ = 45{°}-75{°}), and tensile-split along the discontinuities (θ = 90{°}). The axial strain of the weak and hard rock layers in the composite rock specimen during the loading process was significantly different from that of the θ = 0{°}-45{°} specimens and was almost the same as that of the θ = 60{°}-90{°} specimens. As for the strain localization highlighted in the maximum principal strain field, the θ = 0{°}-30{°} specimens appeared in the rock matrix approximately parallel to the loading direction, while in the θ = 45{°}-90{°} specimens it appeared at the hard and weak rock layer interface.

Automated Plasma Spray (APS) process feasibility study: Plasma spray process development and evaluation

NASA Technical Reports Server (NTRS)

Fetheroff, C. W.; Derkacs, T.; Matay, I. M.

1979-01-01

An automated plasma spray (APS) process was developed to apply two layer (NiCrAlY and ZrO2-12Y2O3) thermal-barrier coatings to aircraft gas turbine engine blade airfoils. The APS process hardware consists of four subsystems: a mechanical blade positioner incorporating two interlaced six-degree-of-freedom assemblies; a noncoherent optical metrology subsystem; a microprocessor-based adaptive system controller; and commercial plasma spray equipment. Over fifty JT9D first stage turbine blades specimens were coated with the APS process in preliminary checkout and evaluation studies. The best of the preliminary specimens achieved an overall coating thickness uniformity of + or - 53 micrometers, much better than is achievable manually. Factors limiting this performance were identified and process modifications were initiated accordingly. Comparative evaluations of coating thickness uniformity for manually sprayed and APS coated specimens were initiated. One of the preliminary evaluation specimens was subjected to a torch test and metallographic evaluation.

Fracture mode, microstructure and temperature-dependent elastic moduli for thermoelectric composites of PbTe-PbS with SiC nanoparticle additions

NASA Astrophysics Data System (ADS)

Ni, Jennifer E.; Case, Eldon D.; Schmidt, Robert D.; Wu, Chun-I.; Hogan, Timothy P.; Trejo, Rosa M.; Lara-Curzio, Edgar; Kanatzidis, Mercouri G.

2013-12-01

Twenty-six (Pb0.95Sn0.05Te)0.92(PbS)0.08-0.055% PbI2-SiC nanoparticle (SiCnp) composite thermoelectric specimens were either hot pressed or pulsed electric current sintered (PECS). Bloating (a thermally induced increase in porosity, P, for as-densified specimens) was observed during annealing at temperatures >603 K for hot-pressed specimens and PECS-processed specimens from wet milled powders, but in contrast seven out of seven specimens densified by PECS from dry milled powders showed no observable bloating following annealing at temperatures up to 936 K. In this study, bloating in the specimens was accessed via thermal annealing induced changes in (i) porosity measured by scanning electron microscopy on fractured specimen surfaces, (ii) specimen volume and (iii) elastic moduli. The moduli were measured by resonant ultrasound spectroscopy. SiCnp additions (1-3.5 vol.%) changed the fracture mode from intergranular to transgranular, inhibited grain growth, and limited bloating in the wet milled PECS specimens. Inhibition of bloating likely occurs due to cleaning of contamination from powder particle surfaces via PECS processing which has been reported previously in the literature.

In Process Measurement of Hydrogen in Welding

DTIC Science & Technology

1986-09-01

Specimen Geometry.........40 Figure 4.8 GTAW Diffusible Hydrogen Specimen Geometry .......... 40 Figure 4.9 Schematic of Specimen Outgassing Container for... GTAW ) and gas metal arc welding (GMAW) have the lowest potentials for hydrogen pickup, while -. the flux-cored arc welding (FCAW) and submerged arc...wire during welding which is the major source of hydrogen in GMAW and GTAW . Although the FCAW process was originally considered an intrinsi- cally low

Influence of Processing Conditions on the Mechanical Behavior and Morphology of Injection Molded Poly(lactic-co-glycolic acid) 85:15

PubMed Central

Fancello, Eduardo Alberto

2017-01-01

Two groups of PLGA specimens with different geometries (notched and unnotched) were injection molded under two melting temperatures and flow rates. The mechanical properties, morphology at the fracture surface, and residual stresses were evaluated for both processing conditions. The morphology of the fractured surfaces for both specimens showed brittle and smooth fracture features for the majority of the specimens. Fracture images of the notched specimens suggest that the surface failure mechanisms are different from the core failure. Polarized light techniques indicated birefringence in all specimens, especially those molded with lower temperature, which suggests residual stress due to rapid solidification. DSC analysis confirmed the existence of residual stress in all PLGA specimens. The specimens molded using the lower injection temperature and the low flow rate presented lower loss tangent values according to the DMA and higher residual stress as shown by DSC, and the photoelastic analysis showed extensive birefringence. PMID:28848605

Specimen preparation for high-resolution cryo-EM

PubMed Central

Passmore, Lori A.; Russo, Christopher J.

2016-01-01

Imaging a material with electrons at near-atomic resolution requires a thin specimen that is stable in the vacuum of the transmission electron microscope. For biological samples, this comprises a thin layer of frozen aqueous solution containing the biomolecular complex of interest. The process of preparing a high-quality specimen is often the limiting step in the determination of structures by single-particle electron cryomicroscopy (cryo-EM). Here we describe a systematic approach for going from a purified biomolecular complex in aqueous solution to high-resolution electron micrographs that are suitable for 3D structure determination. This includes a series of protocols for the preparation of vitrified specimens on various specimen supports, including all-gold and graphene. We also describe techniques for troubleshooting when a preparation fails to yield suitable specimens, and common mistakes to avoid during each part of the process. Finally, we include recommendations for obtaining the highest quality micrographs from prepared specimens with current microscope, detector and support technology. PMID:27572723

Process for measuring low cadmium levels in blood and other biological specimens

DOEpatents

Peterson, David P.; Huff, Edmund A.; Bhattacharyya, Maryka H.

1994-01-01

A process for measuring low levels of cadmium in blood and other biological specimens is provided without interference from high levels of alkali metal contaminants by forming an aqueous solution and without contamination by environmental cadmium absent the proteins from the specimen, selectively removing cadmium from the aqueous solution on an anion exchange resin, thereby removing the alkali metal contaminants, resolubilizing cadmium from the resin to form a second solution and analyzing the second solution for cadmium, the process being carried out in a cadmium-free environment.

Process for measuring low cadmium levels in blood and other biological specimens

DOEpatents

Peterson, David P.; Huff, Edmund A.; Bhattacharyya, Maryka H.

1994-05-03

A process for measuring low levels of cadmium in blood and other biological specimens is provided without interference from high levels of alkali metal contaminants by forming an aqueous solution and without contamination by environmental cadmium absent the proteins from the specimen, selectively removing cadmium from the aqueous solution on an anion exchange resin, thereby removing the alkali metal contaminants, resolubilizing cadmium from the resin to form a second solution and analyzing the second solution for cadmium, the process being carried out in a cadmium-free environment.

Application of SEM and EDX in studying biomineralization in plant tissues.

PubMed

He, Honghua; Kirilak, Yaowanuj

2014-01-01

This chapter describes protocols using formalin-acetic acid-alcohol (FAA) to fix plant tissues for studying biomineralization by means of scanning electron microscopy (SEM) and qualitative energy-dispersive X-ray microanalysis (EDX). Specimen preparation protocols for SEM and EDX mainly include fixation, dehydration, critical point drying (CPD), mounting, and coating. Gold-coated specimens are used for SEM imaging, while gold- and carbon-coated specimens are prepared for qualitative X-ray microanalyses separately to obtain complementary information on the elemental compositions of biominerals. During the specimen preparation procedure for SEM, some biominerals may be dislodged or scattered, making it difficult to determine their accurate locations, and light microscopy is used to complement SEM studies. Specimen preparation protocols for light microscopy generally include fixation, dehydration, infiltration and embedding with resin, microtome sectioning, and staining. In addition, microwave processing methods are adopted here to speed up the specimen preparation process for both SEM and light microscopy.

Experimental and analytical investigation of the fracture processes of boron/aluminum laminates containing notches

NASA Technical Reports Server (NTRS)

Johnson, W. S.; Bigelow, C. A.; Bahei-El-din, Y. A.

1983-01-01

Experimental results for five laminate orientations of boron/aluminum composites containing either circular holes or crack-like slits are presented. Specimen stress-strain behavior, stress at first fiber failure, and ultimate strength were determined. Radiographs were used to monitor the fracture process. The specimens were analyzed with a three-dimensional elastic-elastic finite-element model. The first fiber failures in notched specimens with laminate orientation occurred at or very near the specimen ultimate strength. For notched unidirectional specimens, the first fiber failure occurred at approximately one-half of the specimen ultimate strength. Acoustic emission events correlated with fiber breaks in unidirectional composites, but did not for other laminates. Circular holes and crack-like slits of the same characteristic length were found to produce approximately the same strength reduction. The predicted stress-strain responses and stress at first fiber failure compared very well with test data for laminates containing 0 deg fibers.

Apparatus for automated testing of biological specimens

DOEpatents

Layne, Scott P.; Beugelsdijk, Tony J.

1999-01-01

An apparatus for performing automated testing of infections biological specimens is disclosed. The apparatus comprise a process controller for translating user commands into test instrument suite commands, and a test instrument suite comprising a means to treat the specimen to manifest an observable result, and a detector for measuring the observable result to generate specimen test results.

Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

2012-02-01

Laboratory tests were conducted to determine the fatigue performance of abrasive-waterjet- (AWJ-) machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results of the titanium specimens not only confirmed our previous findings in aluminum dog-bone specimens but in comparison also further enhanced the fatigue performance of the titanium.more » In addition, titanium is known to be difficult to cut, particularly for thick parts, however AWJs cut the material 34% faster han stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred ombination for processing aircraft titanium that is fatigue critical.« less

Inselect: Automating the Digitization of Natural History Collections

PubMed Central

Hudson, Lawrence N.; Blagoderov, Vladimir; Heaton, Alice; Holtzhausen, Pieter; Livermore, Laurence; Price, Benjamin W.; van der Walt, Stéfan; Smith, Vincent S.

2015-01-01

The world’s natural history collections constitute an enormous evidence base for scientific research on the natural world. To facilitate these studies and improve access to collections, many organisations are embarking on major programmes of digitization. This requires automated approaches to mass-digitization that support rapid imaging of specimens and associated data capture, in order to process the tens of millions of specimens common to most natural history collections. In this paper we present Inselect—a modular, easy-to-use, cross-platform suite of open-source software tools that supports the semi-automated processing of specimen images generated by natural history digitization programmes. The software is made up of a Windows, Mac OS X, and Linux desktop application, together with command-line tools that are designed for unattended operation on batches of images. Blending image visualisation algorithms that automatically recognise specimens together with workflows to support post-processing tasks such as barcode reading, label transcription and metadata capture, Inselect fills a critical gap to increase the rate of specimen digitization. PMID:26599208

Inselect: Automating the Digitization of Natural History Collections.

PubMed

Hudson, Lawrence N; Blagoderov, Vladimir; Heaton, Alice; Holtzhausen, Pieter; Livermore, Laurence; Price, Benjamin W; van der Walt, Stéfan; Smith, Vincent S

2015-01-01

The world's natural history collections constitute an enormous evidence base for scientific research on the natural world. To facilitate these studies and improve access to collections, many organisations are embarking on major programmes of digitization. This requires automated approaches to mass-digitization that support rapid imaging of specimens and associated data capture, in order to process the tens of millions of specimens common to most natural history collections. In this paper we present Inselect-a modular, easy-to-use, cross-platform suite of open-source software tools that supports the semi-automated processing of specimen images generated by natural history digitization programmes. The software is made up of a Windows, Mac OS X, and Linux desktop application, together with command-line tools that are designed for unattended operation on batches of images. Blending image visualisation algorithms that automatically recognise specimens together with workflows to support post-processing tasks such as barcode reading, label transcription and metadata capture, Inselect fills a critical gap to increase the rate of specimen digitization.

Replacement/Refurbishment of JSC/NASA POD Specimens

NASA Technical Reports Server (NTRS)

Castner, Willard L.

2010-01-01

The NASA Special NDE certification process requires demonstration of NDE capability by test per NASA-STD-5009. This test is performed with fatigue cracked specimens containing very small cracks. The certification test results are usually based on binomial statistics and must meet a 90/95 Probability of Detection (POD). The assumption is that fatigue cracks are tightly closed, difficult to detect, and inspectors and processes passing such a test are well qualified for inspecting NASA fracture critical hardware. The JSC NDE laboratory has what may be the largest inventory that exists of such fatigue cracked NDE demonstration specimens. These specimens were produced by the hundreds in the late 1980s and early 1990s. None have been produced since that time and the condition and usability of the specimens are questionable.

Acoustic levitation technique for containerless processing at high temperatures in space

NASA Technical Reports Server (NTRS)

Rey, Charles A.; Merkley, Dennis R.; Hammarlund, Gregory R.; Danley, Thomas J.

1988-01-01

High temperature processing of a small specimen without a container has been demonstrated in a set of experiments using an acoustic levitation furnace in the microgravity of space. This processing technique includes the positioning, heating, melting, cooling, and solidification of a material supported without physical contact with container or other surface. The specimen is supported in a potential energy well, created by an acoustic field, which is sufficiently strong to position the specimen in the microgravity environment of space. This containerless processing apparatus has been successfully tested on the Space Shuttle during the STS-61A mission. In that experiment, three samples wer successfully levitated and processed at temperatures from 600 to 1500 C. Experiment data and results are presented.

Standard Reference Specimens in Quality Control of Engineering Surfaces

PubMed Central

Song, J. F.; Vorburger, T. V.

1991-01-01

In the quality control of engineering surfaces, we aim to understand and maintain a good relationship between the manufacturing process and surface function. This is achieved by controlling the surface texture. The control process involves: 1) learning the functional parameters and their control values through controlled experiments or through a long history of production and use; 2) maintaining high accuracy and reproducibility with measurements not only of roughness calibration specimens but also of real engineering parts. In this paper, the characteristics, utilizations, and limitations of different classes of precision roughness calibration specimens are described. A measuring procedure of engineering surfaces, based on the calibration procedure of roughness specimens at NIST, is proposed. This procedure involves utilization of check specimens with waveform, wavelength, and other roughness parameters similar to functioning engineering surfaces. These check specimens would be certified under standardized reference measuring conditions, or by a reference instrument, and could be used for overall checking of the measuring procedure and for maintaining accuracy and agreement in engineering surface measurement. The concept of “surface texture design” is also suggested, which involves designing the engineering surface texture, the manufacturing process, and the quality control procedure to meet the optimal functional needs. PMID:28184115

A Multivariate Evaluation of Factors Affecting the Quality of Freshly Frozen Tissue Specimens.

PubMed

Wang, Tong-Hong; Chen, Chin-Chuan; Liang, Kung-Hao; Chen, Chi-Yuan; Chuang, Wen-Yu; Ueng, Shir-Hwa; Chu, Pao-Hsien; Huang, Chung-Guei; Chen, Tse-Ching; Hsueh, Chuen

2017-08-01

Well-prepared and preserved freshly frozen specimens are indispensable materials for clinical studies. To manage specimen quality and to understand the factors potentially affecting specimen quality during preservation processes, we analyzed the quality of RNA and genomic DNA of various tissues collected between 2002 and 2011 in Linkou Chang Gung Memorial Hospital, Taiwan. During this period, a total of 1059 freshly frozen specimens from eight major cancer categories were examined. It was found that preservation duration, organ origin, and tissue type could all influence the quality of RNA samples. The increased preservation period correlated with decreased RNA quality; the brain, breast, and stomach RNA specimens displayed faster degradation rates than those of other organs, and RNA specimens isolated from tumor tissues were apparently more stable than those of other tissues. These factors could all be used as quality predictors of RNA quality. In contrast, almost all analyses revealed that the genomic DNA samples had good quality, which was not influenced by the aforementioned factors. The results assisted us in determining preservation factors that affect specimen quality, which could provide evidence for improving processes of sample collection and preservation. Furthermore, the results are also useful for researchers to adopt as the evaluation criteria for choosing specimen collection and preservation strategies.

Advanced manufacturing development of a composite empennage component for L-1011 aircraft

NASA Technical Reports Server (NTRS)

1979-01-01

Work on process verification and tooling development continued. The cover process development was completed with the decision to proceed with low resin content prepreg material (34 + or - 3% by weight) in the fabrication of production readiness verification test (PRVT) specimens and the full-scale covers. The structural integrity of the cover/joint design was verified with the successful test of the cover attachment to fuselage ancillary test specimen (H25). Failure occurred, as predicted, in the skin panel away from the fuselage joint at 141 percent of the design ultimate load. With the successful completion of the H25 test, the PRVT cover specimens, which are identical to the H25 ancillary test specimen, were cleared for production. Eight of the twenty cover specimens were fabricated and are in preparation for test. All twenty of the PRVT spar specimens were fabricated and also were prepared for test. The environmental chambers used in the durability test of ten cover and ten spar PRVT specimens were completed and installed in the load reaction frames.

A real-time dashboard for managing pathology processes.

PubMed

Halwani, Fawaz; Li, Wei Chen; Banerjee, Diponkar; Lessard, Lysanne; Amyot, Daniel; Michalowski, Wojtek; Giffen, Randy

2016-01-01

The Eastern Ontario Regional Laboratory Association (EORLA) is a newly established association of all the laboratory and pathology departments of Eastern Ontario that currently includes facilities from eight hospitals. All surgical specimens for EORLA are processed in one central location, the Department of Pathology and Laboratory Medicine (DPLM) at The Ottawa Hospital (TOH), where the rapid growth and influx of surgical and cytology specimens has created many challenges in ensuring the timely processing of cases and reports. Although the entire process is maintained and tracked in a clinical information system, this system lacks pre-emptive warnings that can help management address issues as they arise. Dashboard technology provides automated, real-time visual clues that could be used to alert management when a case or specimen is not being processed within predefined time frames. We describe the development of a dashboard helping pathology clinical management to make informed decisions on specimen allocation and tracking. The dashboard was designed and developed in two phases, following a prototyping approach. The first prototype of the dashboard helped monitor and manage pathology processes at the DPLM. The use of this dashboard helped to uncover operational inefficiencies and contributed to an improvement of turn-around time within The Ottawa Hospital's DPML. It also allowed the discovery of additional requirements, leading to a second prototype that provides finer-grained, real-time information about individual cases and specimens. We successfully developed a dashboard that enables managers to address delays and bottlenecks in specimen allocation and tracking. This support ensures that pathology reports are provided within time frame standards required for high-quality patient care. Given the importance of rapid diagnostics for a number of diseases, the use of real-time dashboards within pathology departments could contribute to improving the quality of patient care beyond EORLA's.

Boundary conditions for diffusion in the pack-aluminizing of nickel.

NASA Technical Reports Server (NTRS)

Sivakumar, R.; Seigle, L. L.; Menon, N. B.

1973-01-01

The surface compositions of nickel specimens coated for various lengths of time in aluminizing packs at 2000 F were studied, in order to obtain information about the kinetics of the pack-cementation process in the formation of aluminide coatings. The results obtained indicate that the surface compositions of the coated nickel specimens are independent of time, at least for time between 0.5 and 20 hrs. Another important observation is that the specimens gained weight during the coating process.

Using Ultrasonic Lamb Waves To Measure Moduli Of Composites

NASA Technical Reports Server (NTRS)

Kautz, Harold E.

1995-01-01

Measurements of broad-band ultrasonic Lamb waves in plate specimens of ceramic-matrix/fiber and metal-matrix/fiber composite materials used to determine moduli of elasticity of materials. In one class of potential applications of concept, Lamb-wave responses of specimens measured and analyzed at various stages of thermal and/or mechanical processing to determine effects of processing, without having to dissect specimens. In another class, structural components having shapes supporting propagation of Lamb waves monitored ultrasonically to identify signs of deterioration and impending failure.

Effect of polishing process on corrosion behavior of 308L stainless steel in high temperature water

NASA Astrophysics Data System (ADS)

Ma, Cheng; Han, En-Hou; Peng, Qunjia; Ke, Wei

2018-06-01

Effect of change in surface composition and roughness by different polishing processes on corrosion of 308L stainless steel in high temperature water was investigated. The investigation was conducted by comparing the corrosion behavior of electropolished specimens with that of the 40 nm-colloidal silica slurry polished specimens. The result revealed that the electropolished specimens had a higher corrosion rate than the colloidal silica slurry polished specimens, which was attributed to formation of an amount of chromium hydroxide and higher roughness of the electropolished surface. Moreover, the ferrite in 308L stainless steel was found to have a higher resistance to corrosion than the austenite matrix.

Processing, structure, and characterizaton of nickel-alumina composites obtained by the partial reduction of zirconia-doped nickel-aluminum oxide and application to the tempering of ceramics

NASA Astrophysics Data System (ADS)

Barbieri, Thomas John

1999-11-01

Partial reduction of the spinel compound NiAl2O4 results in a two phase composite mixture of Ni + Al2O3. The reduction reaction has a volume decrease associated with it, which theoretically could generate large residual stresses, which have the potential to "temper" a ceramic, i.e. to place the surface of a ceramic component into a state of residual compression. As the first step towards tempering a ceramic, it is necessary to demonstrate that appreciable stresses can be generated by this volume change, since they may be relieved by either cracking or diffusional relaxation processes at the high temperature of the reduction reaction. It was necessary to determine the best processing methods to use for producing the tempered specimens. Results are presented from a systematic study on the effect of the variation of processing parameters on the reduction behavior of NiAl2O4 doped with ZrO2. Specimen characteristics of interest were time required for reduction, microstructural development, volume contraction achieved and porosity generated during reduction, and the ability to survive the reduction process without fracturing. These results were applied to the tempering process. A simple specimen geometry was used for tempering which involved an Al 2O3 cylinder bonded to an outer NiAl2O4 ring. Finite element calculations were performed to predict the residual stresses generated by the volume contraction of the ring and the coefficient of thermal expansion, (CTE) mismatch between the Al2O3 core and the reduced composite ring. Stress measurements performed on the Al2 O3 core of each specimen using the "d vs. Sin 2Psi" method of X-ray diffraction indicate that only the CTE-induced stresses remain in the specimens after completion of the tempering process. Microstructural analysis of the tempered specimens was performed to determine if residual stresses were developed during reduction, and what processes occurred to relieve these stresses. The results indicate that stresses are generated during the reduction process, but they are dissipated through catastrophic fracture, cation rearrangement in the lattice, and creep. Further evidence of the presence of residual stresses during reduction was found in a decrease in coarsening rate in tempered specimens.

Five task clusters that enable efficient and effective digitization of biological collections

PubMed Central

Nelson, Gil; Paul, Deborah; Riccardi, Gregory; Mast, Austin R.

2012-01-01

Abstract This paper describes and illustrates five major clusters of related tasks (herein referred to as task clusters) that are common to efficient and effective practices in the digitization of biological specimen data and media. Examples of these clusters come from the observation of diverse digitization processes. The staff of iDigBio (The U.S. National Science Foundation’s National Resource for Advancing Digitization of Biological Collections) visited active biological and paleontological collections digitization programs for the purpose of documenting and assessing current digitization practices and tools. These observations identified five task clusters that comprise the digitization process leading up to data publication: (1) pre-digitization curation and staging, (2) specimen image capture, (3) specimen image processing, (4) electronic data capture, and (5) georeferencing locality descriptions. While not all institutions are completing each of these task clusters for each specimen, these clusters describe a composite picture of digitization of biological and paleontological specimens across the programs that were observed. We describe these clusters, three workflow patterns that dominate the implemention of these clusters, and offer a set of workflow recommendations for digitization programs. PMID:22859876

The effectiveness of inking needle core prostate biopsies for preventing patient specimen identification errors: a technique to address Joint Commission patient safety goals in specialty laboratories.

PubMed

Raff, Lester J; Engel, George; Beck, Kenneth R; O'Brien, Andrea S; Bauer, Meagan E

2009-02-01

The elimination or reduction of medical errors has been a main focus of health care enterprises in the United States since the year 2000. Elimination of errors in patient and specimen identification is a key component of this focus and is the number one goal in the Joint Commission's 2008 National Patient Safety Goals Laboratory Services Program. To evaluate the effectiveness of using permanent inks to maintain specimen identity in sequentially submitted prostate needle biopsies. For a 12-month period, a grossing technician stained each prostate core with permanent ink developed for inking of pathology specimens. A different color was used for each patient, with all the prostate cores from all vials for a particular patient inked with the same color. Five colors were used sequentially: green, blue, yellow, orange, and black. The ink was diluted with distilled water to a consistency that allowed application of a thin, uniform coating of ink along the edges of the prostate core. The time required to ink patient specimens comprising different numbers of vials and prostate biopsies was timed. The number and type of inked specimen discrepancies were evaluated. The identified discrepancy rate for prostate biopsy patients was 0.13%. The discrepancy rate in terms of total number of prostate blocks was 0.014%. Diluted inks adhered to biopsy contours throughout tissue processing. The tissue showed no untoward reactions to the inks. Inking did not affect staining (histochemical or immunohistochemical) or pathologic evaluation. On average, inking prostate needle biopsies increases grossing time by 20%. Inking of all prostate core biopsies with colored inks, in sequential order, is an aid in maintaining specimen identity. It is a simple and effective method of addressing Joint Commission patient safety goals by maintaining specimen identity during processing of similar types of gross specimens. This technique may be applicable in other specialty laboratories and high-volume laboratories, where many similar tissue specimens are processed.

Process Evaluation of AISI 4340 Steel Manufactured by Laser Powder Bed Fusion

NASA Astrophysics Data System (ADS)

Jelis, Elias; Hespos, Michael R.; Ravindra, Nuggehalli M.

2018-01-01

Laser powder bed fusion (L-PBF) involves the consolidation of metal powder, layer by layer, through laser melting and solidification. In this study, process parameters are optimized for AISI 4340 steel to produce dense and homogeneous structures. The optimized process parameters produce mechanical properties at the center of the build plate that are comparable to wrought in the vertical and horizontal orientations after heat treatment and machining. Four subsequent builds are filled with specimens to evaluate the mechanical behavior as a function of location and orientation. Variations in the mechanical properties are likely due to recoater blade interactions with the powder and uneven gas flow. The results obtained in this study are analyzed to assess the reliability and reproducibility of the process. A different build evaluates the performance of near-net-shaped tensile specimens angled 35°-90° from the build plate surface (horizontal). Ductility measurements and surface roughness vary significantly as a function of the build angle. In the stress-relieved and as-built conditions, the mechanical behavior of vertically oriented specimens exhibits somewhat lower and more variable ductility than horizontally oriented specimens. Therefore, several process variables affect the mechanical properties of parts produced by the L-PBF process.

A new specimen management system using RFID technology.

PubMed

Shim, Hun; Uh, Young; Lee, Seung Hwan; Yoon, Young Ro

2011-12-01

The specimen management system with barcode needs to be improved in order to solve inherent problems in work performance. This study describes the application of Radio Frequency Identification (RFID) which is the solution for the problems associated with specimen labeling and management. A new specimen management system and architecture with RFID technology for clinical laboratory was designed. The suggested system was tested in various conditions such as durability to temperature and aspect of effective utilization of new work flow under a virtual hospital clinical laboratory environment. This system demonstrates its potential application in clinical laboratories for improving work flow and specimen management. The suggested specimen management system with RFID technology has advantages in comparison to the traditional specimen management system with barcode in the aspect of mass specimen processing, robust durability of temperature, humidity changes, and effective specimen tracking.

SurePath Specimens Versus ThinPrep Specimen Types on the COBAS 4800 Platform: High-Risk HPV Status and Cytology Correlation in an Ethnically Diverse Bronx Population.

PubMed

Naeem, R C; Goldstein, D Y; Einstein, Mark H; Ramos Rivera, G; Schlesinger, K; Khader, S N; Suhrland, M; Fox, A S

2017-08-01

To compare the cytologic preparations of 130 cervical specimens (from women of various ethnicities at high risk for human papillomavirus [HPV] infection) using the SurePath (SP) collection system with specimens gathered using the ThinPrep (TP) system, as processed on the Cobas 4800 analyzer, to determine which collection method more accurately identifies HPV infection. In our prospective study, specimens were collected from 130 women of various ethnicities residing in or near Bronx County, NY. The SP-collected specimen was first processed for cytologic findings; if clinical HPV testing was requested on that specimen, it was tested using Hybrid Capture II (HC2) methodology. We tested the remnant SP-collected cell concentrate using the Cobas analyzer. Then, the TP-collected and SP-collected specimens were tested in the same run on that analyzer, and the results were compared. We also compared the results with the concurrent cytologic findings. The results were concordant for overall HR-HPV status in 93.8% of cases. Also, a statistically significant lower cycle threshold value was observed with Cobas testing of specimen concentrates tested via the BD SurePath Pap Test (P = .001), suggesting higher sensitivity compared with specimens tested via the ThinPrep Pap Test. Cobas 4800 HPV testing of SP-collected specimen concentrates yields comparable results to TP-collected specimen concentrates. Based on the limited data that we derived, SP collection may be a more favorable methodology than TP collection for HPV testing of individuals at high risk in our ethnically diverse, urban patient population. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Endoscopic ultrasound-guided fine-needle aspiration with liquid-based cytologic preparation in the diagnosis of primary pancreatic lymphoma.

PubMed

Rossi, Esther Diana; Larghi, Alberto; Verna, Elizabeth C; Martini, Maurizio; Galasso, Domenico; Carnuccio, Antonella; Larocca, Luigi Maria; Costamagna, Guido; Fadda, Guido

2010-11-01

The diagnosis subtyping of lymphoma on specimens collected by endoscopic ultrasound fine-needle aspiration (EUS-FNA) can be extremely difficult. When a cytopathologist is available for the on-site evaluation, the diagnosis may be achieved by applying flow cytometric techniques. We describe our experience with immunocytochemistry (ICC) and molecular biology studies applied on EUS-FNA specimens processed with a liquid-based cytologic (LBC) preparation for the diagnosis of primary pancreatic lymphoma (PPL). Three patients with a pancreatic mass underwent EUS-FNA. The collected specimens were processed with the ThinPrep method for the cytologic diagnosis and eventual additional investigations. A morphologic picture consistent with PPL was found on the LBC specimens of the 3 patients. Subsequent ICC and molecular biology studies for immunoglobulin heavy chain gene rearrangement established the diagnosis of pancreatic large B-cell non-Hodgkin lymphoma in 2 patients and a non-Hodgkin lymphoma with plasmoblastic/immunoblastic differentiation in the remaining one. An LBC preparation can be used to diagnose and subtype PPL by applying ICC and molecular biology techniques to specimens collected with EUS-FNA. This method can be an additional processing method for EUS-FNA specimens in centers where on-site cytopathologist expertise is not available.

Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

2010-10-04

Laboratory tests were conducted to determine the fatigue performance of AWJ-machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results not only confirmed the findings of the aluminum dog-bone specimens but also further enhance the fatigue performance. In addition, titanium is known to be notoriously difficult to cutmore » with contact tools while AWJs cut it 34% faster than stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred combination for processing aircraft titanium that is fatigue critical.« less

The Henry Ford Production System: LEAN Process Redesign Improves Service in the Molecular Diagnostic Laboratory

PubMed Central

Cankovic, Milena; Varney, Ruan C.; Whiteley, Lisa; Brown, Ron; D'Angelo, Rita; Chitale, Dhananjay; Zarbo, Richard J.

2009-01-01

Accurate and timely molecular test results play an important role in patient management; consequently, there is a customer expectation of short testing turnaround times. Baseline data analysis revealed that the greatest challenge to timely result generation occurred in the preanalytic phase of specimen collection and transport. Here, we describe our efforts to improve molecular testing turnaround times by focusing primarily on redesign of preanalytic processes using the principles of LEAN production. Our goal was to complete greater than 90% of the molecular tests in less than 3 days. The project required cooperation from different laboratory disciplines as well as individuals outside of the laboratory. The redesigned processes involved defining and standardizing the protocols and approaching blood and tissue specimens as analytes for molecular testing. The LEAN process resulted in fewer steps, approaching the ideal of a one-piece flow for specimens through collection/retrieval, transport, and different aspects of the testing process. The outcome of introducing the LEAN process has been a 44% reduction in molecular test turnaround time for tissue specimens, from an average of 2.7 to 1.5 days. In addition, extending LEAN work principles to the clinician suppliers has resulted in a markedly increased number of properly collected and shipped blood specimens (from 50 to 87%). These continuous quality improvements were accomplished by empowered workers in a blame-free environment and are now being sustained with minimal management involvement. PMID:19661386

Advancing haemostasis automation--successful implementation of robotic centrifugation and sample processing in a tertiary service hospital.

PubMed

Sédille-Mostafaie, Nazanin; Engler, Hanna; Lutz, Susanne; Korte, Wolfgang

2013-06-01

Laboratories today face increasing pressure to automate operations due to increasing workloads and the need to reduce expenditure. Few studies to date have focussed on the laboratory automation of preanalytical coagulation specimen processing. In the present study, we examined whether a clinical chemistry automation protocol meets the preanalytical requirements for the analyses of coagulation. During the implementation of laboratory automation, we began to operate a pre- and postanalytical automation system. The preanalytical unit processes blood specimens for chemistry, immunology and coagulation by automated specimen processing. As the production of platelet-poor plasma is highly dependent on optimal centrifugation, we examined specimen handling under different centrifugation conditions in order to produce optimal platelet deficient plasma specimens. To this end, manually processed models centrifuged at 1500 g for 5 and 20 min were compared to an automated centrifugation model at 3000 g for 7 min. For analytical assays that are performed frequently enough to be targets for full automation, Passing-Bablok regression analysis showed close agreement between different centrifugation methods, with a correlation coefficient between 0.98 and 0.99 and a bias between -5% and +6%. For seldom performed assays that do not mandate full automation, the Passing-Bablok regression analysis showed acceptable to poor agreement between different centrifugation methods. A full automation solution is suitable and can be recommended for frequent haemostasis testing.

37 CFR 1.166 - Specimens.

Code of Federal Regulations, 2014 CFR

2014-07-01

... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES National Processing Provisions Plant Patents § 1.166 Specimens. The applicant may be required to furnish specimens of the plant, or its flower or fruit, in a quantity and at a time in its stage of growth as may be designated, for study and inspection. Such...

37 CFR 1.166 - Specimens.

Code of Federal Regulations, 2012 CFR

2012-07-01

... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES National Processing Provisions Plant Patents § 1.166 Specimens. The applicant may be required to furnish specimens of the plant, or its flower or fruit, in a quantity and at a time in its stage of growth as may be designated, for study and inspection. Such...

37 CFR 1.166 - Specimens.

Code of Federal Regulations, 2013 CFR

2013-07-01

... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES National Processing Provisions Plant Patents § 1.166 Specimens. The applicant may be required to furnish specimens of the plant, or its flower or fruit, in a quantity and at a time in its stage of growth as may be designated, for study and inspection. Such...

37 CFR 1.166 - Specimens.

Code of Federal Regulations, 2011 CFR

2011-07-01

... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES National Processing Provisions Plant Patents § 1.166 Specimens. The applicant may be required to furnish specimens of the plant, or its flower or fruit, in a quantity and at a time in its stage of growth as may be designated, for study and inspection. Such...

49 CFR 40.83 - How do laboratories process incoming specimens?

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.83 How do laboratories... copies of the CCF or any copies of the alcohol testing form. (b) You must comply with applicable provisions of the HHS Guidelines concerning accessioning and processing urine drug specimens. (c) You must...

49 CFR 40.83 - How do laboratories process incoming specimens?

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.83 How do laboratories... copies of the CCF or any copies of the alcohol testing form. (b) You must comply with applicable provisions of the HHS Guidelines concerning accessioning and processing urine drug specimens. (c) You must...

49 CFR 40.83 - How do laboratories process incoming specimens?

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.83 How do laboratories... copies of the CCF or any copies of the alcohol testing form. (b) You must comply with applicable provisions of the HHS Guidelines concerning accessioning and processing urine drug specimens. (c) You must...

49 CFR 40.83 - How do laboratories process incoming specimens?

Code of Federal Regulations, 2011 CFR

2011-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.83 How do laboratories... copies of the CCF or any copies of the alcohol testing form. (b) You must comply with applicable provisions of the HHS Guidelines concerning accessioning and processing urine drug specimens. (c) You must...

49 CFR 40.83 - How do laboratories process incoming specimens?

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.83 How do laboratories... copies of the CCF or any copies of the alcohol testing form. (b) You must comply with applicable provisions of the HHS Guidelines concerning accessioning and processing urine drug specimens. (c) You must...

16 CFR Appendix A to Part 423 - Glossary of Standard Terms

Code of Federal Regulations, 2014 CFR

2014-01-01

... Standard Terms 1. Washing, Machine Methods: a. “Machine wash”—a process by which soil may be removed from.... “Hand wash”—a process by which soil may be manually removed from products or specimens through the use...”—a process by which soil may be removed from products or specimens in a machine which uses any common...

16 CFR Appendix A to Part 423 - Glossary of Standard Terms

Code of Federal Regulations, 2010 CFR

2010-01-01

... Standard Terms 1. Washing, Machine Methods: a. “Machine wash”—a process by which soil may be removed from.... “Hand wash”—a process by which soil may be manually removed from products or specimens through the use...”—a process by which soil may be removed from products or specimens in a machine which uses any common...

16 CFR Appendix A to Part 423 - Glossary of Standard Terms

Code of Federal Regulations, 2012 CFR

2012-01-01

... Standard Terms 1. Washing, Machine Methods: a. “Machine wash”—a process by which soil may be removed from.... “Hand wash”—a process by which soil may be manually removed from products or specimens through the use...”—a process by which soil may be removed from products or specimens in a machine which uses any common...

16 CFR Appendix A to Part 423 - Glossary of Standard Terms

Code of Federal Regulations, 2011 CFR

2011-01-01

... Standard Terms 1. Washing, Machine Methods: a. “Machine wash”—a process by which soil may be removed from.... “Hand wash”—a process by which soil may be manually removed from products or specimens through the use...”—a process by which soil may be removed from products or specimens in a machine which uses any common...

16 CFR Appendix A to Part 423 - Glossary of Standard Terms

Code of Federal Regulations, 2013 CFR

2013-01-01

... Standard Terms 1. Washing, Machine Methods: a. “Machine wash”—a process by which soil may be removed from.... “Hand wash”—a process by which soil may be manually removed from products or specimens through the use...”—a process by which soil may be removed from products or specimens in a machine which uses any common...

Ultrasonic tomography for in-process measurements of temperature in a multi-phase medium

DOEpatents

Beller, Laurence S.

1993-01-01

A method and apparatus for the in-process measurement of internal particulate temperature utilizing ultrasonic tomography techniques to determine the speed of sound through a specimen material. Ultrasonic pulses are transmitted through a material, which can be a multi-phase material, over known flight paths and the ultrasonic pulse transit times through all sectors of the specimen are measured to determine the speed of sound. The speed of sound being a function of temperature, it is possible to establish the correlation between speed of sound and temperature, throughout a cross-section of the material, which correlation is programmed into a computer to provide for a continuous in-process measurement of temperature throughout the specimen.

Comparison of blood specimens from plain and gel vacuum blood collection tubes.

PubMed

Wiwanitkit, V

2001-05-01

This study was set in the Division of Laboratory Medicine, Chulalongkorn Hospital. All 2,000 blood specimens were randomly collected using evacuated blood collection by plain or gel vacuum tubes. After collection, each specimen was considered and judged using criteria of specimen rejection to determine how proper the specimen presentations were. All data were reviewed, collected and interpreted. It revealed that there were only 20 (1%) improper specimens and all were improper in quality. There was no significant difference between the ratio of improper specimens in both groups (P > 0.30). From this study, it revealed that efficacy of both types of vacuum tubes was not different. The new gel vacuum tube seems to be an effective tool in the evacuated blood collection system due to its advantage in reduction of time in specimen processing.

The influence of flame hardening process to aluminum 7075 series on the mechanical strength and micro structure

NASA Astrophysics Data System (ADS)

Koin, Sudibtia Titio; Triyono, Teguh; Surojo, Eko

2018-02-01

The 7075 series alloys are heat treatable wrought aluminum alloys based on the Al-Zn-Mg(-Cu) system. They are widely used in high-performance structural aerospace and transportation applications. Apart from compositional, casting and thermo-mechanical processing effects, the balance of properties is also significantly influenced by the way in which the materials are heat-treated. This paper describes the effect of flame hardening process to aluminum 7075 series on the increasing hardness, tensile strength, and evolution of microstructure. A test specimen had made by machining process and flame heating. Temperature of solution heat treatment is varied on 350 °C, 400 °C, 450 °C and 500 °C. After that process a test specimen would be quenched at nitrate-nitrite liquid during 45 minutes and artificial aging at 120°C until two days. The testing specimen consist of hardness and tensile strength according to ASTM. The result showed that specimen had precipitation on microstructure lead to an increase in aluminum properties. On the temperature 450°C solution heat treatment, the aluminum properties reached the highest value, namely, hardness of 129 HVN and tensile strength 570 MPa.

Evaluation of Ultrasonic Fiber Structure Extraction Technique Using Autopsy Specimens of Liver

NASA Astrophysics Data System (ADS)

Yamaguchi, Tadashi; Hirai, Kazuki; Yamada, Hiroyuki; Ebara, Masaaki; Hachiya, Hiroyuki

2005-06-01

It is very important to diagnose liver cirrhosis noninvasively and correctly. In our previous studies, we proposed a processing technique to detect changes in liver tissue in vivo. In this paper, we propose the evaluation of the relationship between liver disease and echo information using autopsy specimens of a human liver in vitro. It is possible to verify the function of a processing parameter clearly and to compare the processing result and the actual human liver tissue structure by in vitro experiment. In the results of our processing technique, information that did not obey a Rayleigh distribution from the echo signal of the autopsy liver specimens was extracted depending on changes in a particular processing parameter. The fiber tissue structure of the same specimen was extracted from a number of histological images of stained tissue. We constructed 3D structures using the information extracted from the echo signal and the fiber structure of the stained tissue and compared the two. By comparing the 3D structures, it is possible to evaluate the relationship between the information that does not obey a Rayleigh distribution of the echo signal and the fibrosis structure.

Investigation of solidification in zero-gravity environment; M553 sphere forming experiment. Phase C: Evaluation of Skylab specimens. [physical and mechanical properties of metal spheres formed under weightless conditions

NASA Technical Reports Server (NTRS)

Kattamis, T. Z.

1973-01-01

Results on specimen evaluation and discussion of solidification behavior in each case are reported in the following order: (1) specimen SL-1.6, (2) specimen SL-2.8, (3) specimen SL-2.4, (4) specimen SL-1.10 and (5) specimen SL-1.11. Comparison is made with ground-processed specimens of similar composition, whenever pertinent and meaningful. Among the nondestructive evaluation methods the measurement of sphericity was conducted by micrometric and shadowgraphic techniques. The intricate shape of specimens in some cases appeared difficult to define. In measuring the density, liquid penetration inside cavities that outcrop on the surface was avoided by sealing off these cavities. Among the destructive evaluation methods the use of the Quantimet 720 required particular attention, because of the small difference in contrast between second phases and micropores. With regard to microporosity microvoids in the core of some specimens were so fine that X-ray microradiography had to be used.

[Comparative study of cone-beam CT and spiral CT in measuring the length of styloid process].

PubMed

Song, Y S; Liu, L F

2018-06-19

Objective: To compare the difference of measuring the length of styloid process between spiral CT with high resolution and cone-beam CT(CBCT). Methods: Five specimens (including 5 pairs of styloid processes) were selected randomly from the Anatomy Laboratory of Otolaryngology Department, all the specimens underwent spiral CT with high resolution and cone-beam CT retrospectively.With the original DICOM data, the styloid processes were shown in one plate by multiple plate reconstruction technique, and later the length of styloid processes of each specimen were measured separately by software NNT Viewer (to CBCT) or Osrix (to spiral CT with high resolution). Results: The length of styloid processes measured by CBCT and spiral CT was (26.8±5.5) mm and (27.1±5.4) mm respectively, and there was no statistical difference between the two groups. Conclusion: In respect of measuring the length of styloid process, the CBCT has the same value in clinical practice comparing to spiral CT with high resolution.

Microstructural effects on the deformation and fracture of the alloy Ti-25Al-10Nb-3B-1Mo. Final report, 1 July 1988-15 December 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, C.H.

1992-12-01

The effects of microstructure and temperature on tensile and fracture behavior were explored for the titanium aluminide alloy Ti-25Al-lONb-3V-lMo (atomic percent). Three microstructures were selected for this study in an attempt to determine the role of the individual microstructural constituents. the three microstructures studied were an alpha-2 + beta processed microstructure with a fine Widmanstaetten microstructure, a beta processed microstructure with a fine Widmanstaetten microstructure, and a beta processed microstructure with a coarse Widmanstaetten microstructure. Tensile testing of both round and flat specimens was conducted in vacuum at elevated temperature and in air at room and elevated temperatures. Extensive fractographymore » and specimen sectioning were used to study tensile deformation and the effects of environment on this alloy. Room temperature fracture toughness testing using compact tension specimens was conducted. Elevated temperature toughness testing was performed using J-bend bar specimens in an air environment. Again, extensive fractography and specimen sectioning were used to study the elevated temperature toughening mechanisms of this alloy.... Titanium, Titanium aluminide, Intermetallic, Fracture toughness, Tensile behavior, Fractography environmental interaction.« less

A real-time dashboard for managing pathology processes

PubMed Central

Halwani, Fawaz; Li, Wei Chen; Banerjee, Diponkar; Lessard, Lysanne; Amyot, Daniel; Michalowski, Wojtek; Giffen, Randy

2016-01-01

Context: The Eastern Ontario Regional Laboratory Association (EORLA) is a newly established association of all the laboratory and pathology departments of Eastern Ontario that currently includes facilities from eight hospitals. All surgical specimens for EORLA are processed in one central location, the Department of Pathology and Laboratory Medicine (DPLM) at The Ottawa Hospital (TOH), where the rapid growth and influx of surgical and cytology specimens has created many challenges in ensuring the timely processing of cases and reports. Although the entire process is maintained and tracked in a clinical information system, this system lacks pre-emptive warnings that can help management address issues as they arise. Aims: Dashboard technology provides automated, real-time visual clues that could be used to alert management when a case or specimen is not being processed within predefined time frames. We describe the development of a dashboard helping pathology clinical management to make informed decisions on specimen allocation and tracking. Methods: The dashboard was designed and developed in two phases, following a prototyping approach. The first prototype of the dashboard helped monitor and manage pathology processes at the DPLM. Results: The use of this dashboard helped to uncover operational inefficiencies and contributed to an improvement of turn-around time within The Ottawa Hospital's DPML. It also allowed the discovery of additional requirements, leading to a second prototype that provides finer-grained, real-time information about individual cases and specimens. Conclusion: We successfully developed a dashboard that enables managers to address delays and bottlenecks in specimen allocation and tracking. This support ensures that pathology reports are provided within time frame standards required for high-quality patient care. Given the importance of rapid diagnostics for a number of diseases, the use of real-time dashboards within pathology departments could contribute to improving the quality of patient care beyond EORLA's. PMID:27217974

Effects of Build Orientation on Surface Morphology and Bone Cell Activity of Additively Manufactured Ti6Al4V Specimens.

PubMed

Weißmann, Volker; Drescher, Philipp; Seitz, Hermann; Hansmann, Harald; Bader, Rainer; Seyfarth, Anika; Klinder, Annett; Jonitz-Heincke, Anika

2018-05-29

Additive manufacturing of lightweight or functional structures by selective laser beam (SLM) or electron beam melting (EBM) is widespread, especially in the field of medical applications. SLM and EBM processes were applied to prepare Ti6Al4V test specimens with different surface orientations (0°, 45° and 90°). Roughness measurements of the surfaces were conducted and cell behavior on these surfaces was analyzed. Hence, human osteoblasts were seeded on test specimens to determine cell viability (metabolic activity, live-dead staining) and gene expression of collagen type 1 (Col1A1), matrix metalloprotease (MMP) 1 and its natural inhibitor, TIMP1, after 3 and 7 days. The surface orientation of specimens during the manufacturing process significantly influenced the roughness. Surface roughness showed significant impact on cellular viability, whereas differences between the time points day 3 and 7 were not found. Collagen type 1 mRNA synthesis rates in human osteoblasts were enhanced with increasing roughness. Both manufacturing techniques further influenced the induction of bone formation process in the cell culture. Moreover, the relationship between osteoblastic collagen type 1 mRNA synthesis rates and specimen orientation during the building process could be characterized by functional formulas. These findings are useful in the designing of biomedical applications and medical devices.

Bloating in (Pb0.95Sn0.05Te)0.92(PbS)0.08-0.055%PbI2 Thermoelectric Specimens as a Result of Processing Conditions

NASA Astrophysics Data System (ADS)

Ni, Jennifer E.; Case, Eldon D.; Stewart, Ryan; Wu, Chun-I.; Hogan, Timothy P.; Kanatzidis, Mercouri G.

2012-06-01

Lead chalcogenides such as (Pb0.95Sn0.05Te)0.92(PbS)0.08-0.055%PbI2 have received attention due to their encouraging thermoelectric properties. For the hot pressing (HP) and pulsed electric current sintering (PECS) techniques used in this study, decomposition reactions can generate porosity (bloating). Porosity in turn can degrade electrical, thermal, and mechanical properties. In this study, microstructural observations (scanning electron microscopy) and room-temperature elasticity measurements (resonant ultrasound spectroscopy) were used to characterize bloating generated during post-densification anneals. Although every HP specimen bloated during post-densification annealing, no bloating was observed for the PECS specimens processed from dry milled only powders. The lack of bloating for the annealed PECS specimens may be related to the electrical discharge intrinsic in the PECS process, which reportedly cleans the powder particle surfaces during densification.

Influence of gross specimen sampling on the incidence of incidental prostatic carcinoma in cystoprostatectomy specimens of patients with bladder carcinoma.

PubMed

Mlakar, J; Volavšek, M

2016-03-01

Reported prostate cancer incidence rates vary greatly among cystoprostatectomy samples. We investigated how the thoroughness of prostate sampling influences prostatic carcinoma incidence in bladder cancer patients. In a retrospective study, 313 cystoprostatectomy cases of urinary bladder carcinoma were analysed for the presence of concurrent prostatic carcinoma. Patients were divided into two groups: patients who had undergone the operation before and after 2007, when a policy of preferably complete prostate sampling in cystoprostatectomy specimens was introduced at our institution. Cases processed after the 2007 recommended sampling changes had a significantly higher rate of incidental prostatic carcinoma and clinically significant prostatic carcinoma than the pre-2007 group (p < 0.0001 and p = 0.003, respectively). Complete prostate processing in cystoprostatectomy specimens results in a higher incidence of incidental prostatic carcinoma than with partial processing. More patients with clinically significant prostate cancer are consequently discovered. In conclusion, we believe that complete prostate sampling should be mandatory.

Comparison of contamination of femoral heads and pre-processed bone chips during hip revision arthroplasty.

PubMed

Mathijssen, N M C; Sturm, P D; Pilot, P; Bloem, R M; Buma, P; Petit, P L; Schreurs, B W

2013-12-01

With bone impaction grafting, cancellous bone chips made from allograft femoral heads are impacted in a bone defect, which introduces an additional source of infection. The potential benefit of the use of pre-processed bone chips was investigated by comparing the bacterial contamination of bone chips prepared intraoperatively with the bacterial contamination of pre-processed bone chips at different stages in the surgical procedure. To investigate baseline contamination of the bone grafts, specimens were collected during 88 procedures before actual use or preparation of the bone chips: in 44 procedures intraoperatively prepared chips were used (Group A) and in the other 44 procedures pre-processed bone chips were used (Group B). In 64 of these procedures (32 using locally prepared bone chips and 32 using pre-processed bone chips) specimens were also collected later in the procedure to investigate contamination after use and preparation of the bone chips. In total, 8 procedures had one or more positive specimen(s) (12.5 %). Contamination rates were not significantly different between bone chips prepared at the operating theatre and pre-processed bone chips. In conclusion, there was no difference in bacterial contamination between bone chips prepared from whole femoral heads in the operating room and pre-processed bone chips, and therefore, both types of bone allografts are comparable with respect to risk of infection.

Pre-aging time dependence of microstructure and mechanical properties in nanostructured Al-2wt%Cu alloy

NASA Astrophysics Data System (ADS)

Azad, Bahram; Borhani, Ehsan

2016-03-01

This work is focused on the effect of pre-aging time on the properties of Al-2wt%Cu alloy processed by accumulative roll bonding (ARB) process. Following aged at 190 °C for 10 or 30 min, the samples were deformed up to a strain of 4.8 by the ARB process. The microstructure evolution was investigated by transmission electron microscope and electron backscattering diffraction analyzes. The results showed that the Al2Cu precipitates were formed with different sizes due to the different pre-aging times and the finer precipitates were more effective on the formation of high angle grain boundaries during the ARB process. The grain size of Aged-10 min and Aged-30 min specimens decreased to 400 nm and 420 nm, respectively, after 6 cycles of the ARB process. Also, the final texture after 6 cycles of the ARB process, shown in the {111} pole figure, were different depending on the starting microstructures. The mechanical properties of specimens were investigated by the Vickers microhardness measurements and the tensile tests. The results showed that the mechanical properties are affected by the starting microstructure. The mechanical properties of Aged-10 min specimen were different compared to Aged-30 min specimen due to the different size of the pre-existing precipitates. Although by continuing process, the precipitates were probably dissolved due to the heavy deformation.

Manufacture of composite test specimens for delamination studies

NASA Technical Reports Server (NTRS)

Sumich, M.

1989-01-01

This paper describes the process for manufacturing high-quality test specimens for uses in evaluations of interlaminar tensile strength of laminated composites. The chosen specimen configuration is a curved beam which experiences interlaminar tension in the region of greatest curvature when the beam is subjected to 'opening' forces. The manufacturing process uses a lock-mold tooling approach, the principle of which relies upon the difference in coefficients of thermal expansion between the internal rubber mandrel and the surrounding steel female mold. With this method, compaction pressures above those provided by a typical autoclave can be achieved.

Ultrasonic tomography for in-process measurements of temperature in a multi-phase medium

DOEpatents

Beller, L.S.

1993-01-26

A method and apparatus are described for the in-process measurement of internal particulate temperature utilizing ultrasonic tomography techniques to determine the speed of sound through a specimen material. Ultrasonic pulses are transmitted through a material, which can be a multi-phase material, over known flight paths and the ultrasonic pulse transit times through all sectors of the specimen are measured to determine the speed of sound. The speed of sound being a function of temperature, it is possible to establish the correlation between speed of sound and temperature, throughout a cross-section of the material, which correlation is programmed into a computer to provide for a continuous in-process measurement of temperature throughout the specimen.

Rapid and reliable identification of Gram-negative bacteria and Gram-positive cocci by deposition of bacteria harvested from blood cultures onto the MALDI-TOF plate.

PubMed

Barnini, Simona; Ghelardi, Emilia; Brucculeri, Veronica; Morici, Paola; Lupetti, Antonella

2015-06-18

Rapid identification of the causative agent(s) of bloodstream infections using the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) methodology can lead to increased empirical antimicrobial therapy appropriateness. Herein, we aimed at establishing an easier and simpler method, further referred to as the direct method, using bacteria harvested by serum separator tubes from positive blood cultures and placed onto the polished steel target plate for rapid identification by MALDI-TOF. The results by the direct method were compared with those obtained by MALDI-TOF on bacteria isolated on solid media. Identification of Gram-negative bacilli was 100 % concordant using the direct method or MALDI-TOF on isolated bacteria (96 % with score > 2.0). These two methods were 90 % concordant on Gram-positive cocci (32 % with score > 2.0). Identification by the SepsiTyper method of Gram-positive cocci gave concordant results with MALDI-TOF on isolated bacteria in 87 % of cases (37 % with score > 2.0). The direct method herein developed allows rapid identification (within 30 min) of Gram-negative bacteria and Gram-positive cocci from positive blood cultures and can be used to rapidly report reliable and accurate results, without requiring skilled personnel or the use of expensive kits.

Molecular markers: Implications for cytopathology and specimen collection.

PubMed

VanderLaan, Paul A

2015-08-01

Cytologic specimens obtained through minimally invasive biopsy techniques are increasingly being used as principle diagnostic specimens for tumors arising in multiple sites. The number and scope of ancillary tests performed on these specimens have grown substantially over the past decade, including many molecular markers that not only can aid in formulating accurate and specific diagnoses but also can provide prognostic or therapeutic information to help direct clinical decisions. Thus, the cytopathologist needs to ensure that adequate material is collected and appropriately processed for the study of relevant molecular markers, many of which are specific to tumor site. This brief review covers considerations for effective cytologic specimen collection and processing to ensure diagnostic and testing success. In addition, a general overview is provided of molecular markers pertinent to tumors from a variety of sites. The recognition of these established and emerging molecular markers by cytopathologists is an important step toward realizing the promise of personalized medicine. © 2015 American Cancer Society.

Evaluation of superplastic forming and co-diffusion bonding of Ti-6Al-4V titanium alloy expanded sandwich structures

NASA Technical Reports Server (NTRS)

Arvin, G. H.; Israeli, L.; Stolpestad, J. H.; Stacher, G. W.

1981-01-01

The application of the superplastic forming/diffusion bonding (SPF/DB) process to supersonic cruise research is investigated. The capability of an SPF/DB titanium structure to meet the structural requirements of the inner wing area of the NASA arrow-wing advanced supersonic transport design is evaluated. Selection of structural concepts and their optimization for minimum weight, SPF/DB process optimization, fabrication of representative specimens, and specimen testing and evaluation are described. The structural area used includes both upper and lower wing panels, where the upper wing panel is used for static compression strength evaluation and the lower panel, in tension, is used for fracture mechanics evaluations. The individual test specimens, cut from six large panels, consist of 39 static specimens, 10 fracture mechanics specimens, and one each full size panel for compression stability and fracture mechanics testing. Tests are performed at temperatures of -54 C (-65 F), room temperature, and 260 C (500 F).

Processing postmortem specimens with C18-carboxypropylbetaine and analysis by PCR to develop an antemortem test for Mycobacterium avium infections in ducks.

PubMed

Thornton, C G; Cranfield, M R; MacLellan, K M; Brink, T L; Strandberg, J D; Carlin, E A; Torrelles, J B; Maslow, J N; Hasson, J L; Heyl, D M; Sarro, S J; Chatterjee, D; Passen, S

1999-03-01

Mycobacterium avium is the causative agent of the avian mycobacteriosis commonly known as avian tuberculosis (ATB). This infection causes disseminated disease, is difficult to diagnose, and is of serious concern because it causes significant mortality in birds. A new method was developed for processing specimens for an antemortem screening test for ATB. This novel method uses the zwitterionic detergent C18-carboxypropylbetaine (CB-18). Blood, bone marrow, bursa, and fecal specimens from 28 ducks and swabs of 20 lesions were processed with CB-18 for analysis by smear, culture, and polymerase chain reaction (PCR). Postmortem examination confirmed nine of these birds as either positive or highly suspect for disseminated disease. The sensitivities of smear, culture, and PCR, relative to postmortem analysis and independent of specimen type, were 44.4%, 88.9%, and 100%, respectively, and the specificities were 84.2%, 57.9%, and 15.8%, respectively. Reductions in specificity were due primarily to results among fecal specimens. However, these results were clustered among a subset of birds, suggesting that these tests actually identified birds in early stages of the disease. Restriction fragment length polymorphism mapping identified one strain of M. avium (serotype 1) that was isolated from lesions, bursa, bone marrow, blood, and feces of all but three of the culture-positive birds. In birds with confirmed disease, blood had the lowest sensitivity and the highest specificity by all diagnostic methods. Swabs of lesions provided the highest sensitivity by smear and culture (33.3% and 77.8%, respectively), whereas fecal specimens had the highest sensitivity by PCR (77.8%). The results of this study indicate that processing fecal specimens with CB-18, followed by PCR analysis, may provide a valuable first step for monitoring the presence of ATB in birds.

Weathering characteristics and moisture uptake properties of wood coated with water-borne sol-gel thin films

Treesearch

M. A. Tshabalala; C. Starr; N. R. Sutherland

2010-01-01

In this study, wood specimens were coated with water-borne silsesquioxane oligomers by an in situ sol-gel deposition process. The effect of these water-borne sol-gel thin films on weathering characteristics and moisture-uptake properties of the wood specimens were investigated. The weathering characteristics were investigated by exposure of the specimens to artificial...

Bolted Joints in Three Axially Braided Carbon Fibre/Epoxy Textile Composites with Moulded-in and Drilled Fastener Holes

NASA Astrophysics Data System (ADS)

Ataş, Akın; Gautam, Mayank; Soutis, Constantinos; Potluri, Prasad

2017-04-01

Experimental behaviour of bolted joints in triaxial braided (0°/±45°) carbon fibre/epoxy composite laminates with drilled and moulded-in fastener holes has been investigated in this paper. Braided laminates were manufactured by vacuum infusion process using 12 K T700S carbon fibres (for bias and axial tows) and Araldite LY-564 epoxy resin. Moulded-in fastener holes were formed using guide pins which were inserted in the braided structure prior to the vacuum infusion process. The damage mechanism of the specimens was investigated using ultrasonic C-Scan technique. The specimens were dimensioned to obtain a bearing mode of failure. The bearing strength of the specimens with moulded-in hole was reduced in comparison to the specimens with drilled hole, due to the increased fibre misalignment angle following the pin insertion procedure. An improvement on the bearing strength of moulded-in hole specimens might be developed if the specimen dimensions would be prepared for a net-tension mode of failure where the fibre misalignment would not have an effect as significant as in the case of bearing failure mode, but this mode should be avoided since it leads to sudden catastrophic failures.

An experimental study on fracture mechanical behavior of rock-like materials containing two unparallel fissures under uniaxial compression

NASA Astrophysics Data System (ADS)

Huang, Yan-Hua; Yang, Sheng-Qi; Tian, Wen-Ling; Zeng, Wei; Yu, Li-Yuan

2016-06-01

Strength and deformability characteristics of rock with pre-existing fissures are governed by cracking behavior. To further research the effects of pre-existing fissures on the mechanical properties and crack coalescence process, a series of uniaxial compression tests were carried out for rock-like material with two unparallel fissures. In the present study, cement, quartz sand, and water were used to fabricate a kind of brittle rock-like material cylindrical model specimen. The mechanical properties of rock-like material specimen used in this research were all in good agreement with the brittle rock materials. Two unparallel fissures (a horizontal fissure and an inclined fissure) were created by inserting steel during molding the model specimen. Then all the pre-fissured rock-like specimens were tested under uniaxial compression by a rock mechanics servo-controlled testing system. The peak strength and Young's modulus of pre-fissured specimen all first decreased and then increased when the fissure angle increased from 0° to 75°. In order to investigate the crack initiation, propagation and coalescence process, photographic monitoring was adopted to capture images during the entire deformation process. Moreover, acoustic emission (AE) monitoring technique was also used to obtain the AE evolution characteristic of pre-fissured specimen. The relationship between axial stress, AE events, and the crack coalescence process was set up: when a new crack was initiated or a crack coalescence occurred, the corresponding axial stress dropped in the axial stress-time curve and a big AE event could be observed simultaneously. Finally, the mechanism of crack propagation under microscopic observation was discussed. These experimental results are expected to increase the understanding of the strength failure behavior and the cracking mechanism of rock containing unparallel fissures.

An improved FIB sample preparation technique for site-specific plan-view specimens: A new cutting geometry.

PubMed

Li, Chen; Habler, Gerlinde; Baldwin, Lisa C; Abart, Rainer

2018-01-01

Focused ion beam (FIB) sample preparation technique in plan-view geometry allows direct correlations of the atomic structure study via transmission electron microscopy with micrometer-scale property measurements. However, one main technical difficulty is that a large amount of material must be removed underneath the specimen. Furthermore, directly monitoring the milling process is difficult unless very large material volumes surrounding the TEM specimen site are removed. In this paper, a new cutting geometry is introduced for FIB lift-out sample preparation with plan-view geometry. Firstly, an "isolated" cuboid shaped specimen is cut out, leaving a "bridge" connecting it with the bulk material. Subsequently the two long sides of the "isolated" cuboid are wedged, forming a triangular prism shape. A micromanipulator needle is used for in-situ transfer of the specimen to a FIB TEM grid, which has been mounted parallel with the specimen surface using a simple custom-made sample slit. Finally, the grid is transferred to the standard FIB grid holder for final thinning with standard procedures. This new cutting geometry provides clear viewing angles for monitoring the milling process, which solves the difficulty of judging whether the specimen has been entirely detached from the bulk material, with the least possible damage to the surrounding materials. With an improved success rate and efficiency, this plan-view FIB lift-out specimen preparation technique should have a wide application for material science. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Tracking Polymer Cure Via Embedded Optical Fibers

NASA Technical Reports Server (NTRS)

Dean, David L.; Davidson, T. Fred

1993-01-01

Fourier-transform infrared spectroscopy applied in interior of specimen of material by bringing infrared light through specimen in optical fiber. Light interacts with material via evanescent-wave effect. Spectra obtained in this way at various times during curing process also combined with data from ultrasonic, thermographic, and dielectric-impedance monitoring, and other measurement techniques to obtain more complete characterization of progress of curing process.

Effects of laser-shock processing on the microstructure and surface mechanical properties of hadfield manganese steel

NASA Astrophysics Data System (ADS)

Chu, J. P.; Rigsbee, J. M.; Banaś, G.; Lawrence, F. V.; Elsayed-Ali, H. E.

1995-06-01

The effects of laser-shock processing (LSP) on the microstructure, hardness, and residual stress of Hadfield manganese (1 pct C and 14 pct Mn) steels were studied. Laser-shock processing was performed using a Nd: glass phosphate laser with 600 ps pulse width and up to 120 J/pulse energy at power density above 1012 W/cm2. The effects of cold rolling and shot peening were also studied for comparison. Laser-shock processing caused extensive formation of ɛ hexagonal close-packed (hep) martensite (35 vol pct), producing up to a 130 pct increase of surface hardness. The surface hardness increase was 40 to 60 pct for the shot-peened specimen and about 60 pct for the cold-rolled specimen. The LSP strengthening effect on Hadfield steel was attributed to the combined effects of the partial dislocation/stacking fault arrays and the grain refinement due to the presence of the ɛ-hcp martensite. For the cold-rolled and shot-peened specimens, the strengthening was a result of ɛ-hcp martensite and twins with dislocation effects, respectively. Shot peening resulted in a relatively higher compressive residual stress throughout the specimen than LSP.

Improved image processing of road pavement defect by infrared thermography

NASA Astrophysics Data System (ADS)

Sim, Jun-Gi

2018-03-01

This paper intends to achieve improved image processing for the clear identification of defects in damaged road pavement structure using infrared thermography non-destructive testing (NDT). To that goal, 4 types of pavement specimen including internal defects were fabricated to exploit the results obtained by heating the specimens by natural light. The results showed that defects located down to a depth of 3 cm could be detected by infrared thermography NDT using the improved image processing method.

A microcomputer system for clinical bacteriology: experience of 12 months' trial.

PubMed Central

Courcol, R J; Roussel-Delvallez, M; Martin, G R

1982-01-01

A data processing system using microcomputers was developed in a hospital bacteriology laboratory processing more than 60 000 specimens yearly. The purchase price of the hardware was frs 200 000 (17 500 pounds) and the software was written by the authors. The system has been running since May 1980 without general breakdown. The present configuration allows the processing of specimens, enquiries, scientific and administrative tasks but multiprogramming and cumulative reports are not possible. PMID:7107962

Predictive Analytics to Support Real-Time Management in Pathology Facilities.

PubMed

Lessard, Lysanne; Michalowski, Wojtek; Chen Li, Wei; Amyot, Daniel; Halwani, Fawaz; Banerjee, Diponkar

2016-01-01

Predictive analytics can provide valuable support to the effective management of pathology facilities. The introduction of new tests and technologies in anatomical pathology will increase the volume of specimens to be processed, as well as the complexity of pathology processes. In order for predictive analytics to address managerial challenges associated with the volume and complexity increases, it is important to pinpoint the areas where pathology managers would most benefit from predictive capabilities. We illustrate common issues in managing pathology facilities with an analysis of the surgical specimen process at the Department of Pathology and Laboratory Medicine (DPLM) at The Ottawa Hospital, which processes all surgical specimens for the Eastern Ontario Regional Laboratory Association. We then show how predictive analytics could be used to support management. Our proposed approach can be generalized beyond the DPLM, contributing to a more effective management of pathology facilities and in turn to quicker clinical diagnoses.

Examining Mechanical Strength Characteristics of Selective Inhibition Sintered HDPE Specimens Using RSM and Desirability Approach

NASA Astrophysics Data System (ADS)

Rajamani, D.; Esakki, Balasubramanian

2017-09-01

Selective inhibition sintering (SIS) is a powder based additive manufacturing (AM) technique to produce functional parts with an inexpensive system compared with other AM processes. Mechanical properties of SIS fabricated parts are of high dependence on various process parameters importantly layer thickness, heat energy, heater feedrate, and printer feedrate. In this paper, examining the influence of these process parameters on evaluating mechanical properties such as tensile and flexural strength using Response Surface Methodology (RSM) is carried out. The test specimens are fabricated using high density polyethylene (HDPE) and mathematical models are developed to correlate the control factors to the respective experimental design response. Further, optimal SIS process parameters are determined using desirability approach to enhance the mechanical properties of HDPE specimens. Optimization studies reveal that, combination of high heat energy, low layer thickness, medium heater feedrate and printer feedrate yielded superior mechanical strength characteristics.

Effect of Cooling Rate on SCC Susceptibility of β-Processed Ti-6Al-4V Alloy in 0.6M NaCl Solution

NASA Astrophysics Data System (ADS)

Ahn, Soojin; Park, Jiho; Jeong, Daeho; Sung, Hyokyung; Kwon, Yongnam; Kim, Sangshik

2018-03-01

The effects of cooling rate on the stress corrosion cracking (SCC) susceptibility of β-processed Ti-6Al-4V (Ti64) alloy, including BA/S specimen with furnace cooling and BQ/S specimen with water quenching, were investigated in 0.6M NaCl solution under various applied potentials using a slow strain rate test technique. It was found that the SCC susceptibility of β-processed Ti64 alloy in aqueous NaCl solution decreased with fast cooling rate, which was particularly substantial under an anodic applied potential. The micrographic and fractographic analyses suggested that the enhancement with fast cooling rate was related to the random orientation of acicular α platelets in BQ/S specimen. Based on the experimental results, the effect of cooling rate on the SCC behavior of β-processed Ti64 alloy in aqueous NaCl solution was discussed.

Predictive Analytics to Support Real-Time Management in Pathology Facilities

PubMed Central

Lessard, Lysanne; Michalowski, Wojtek; Chen Li, Wei; Amyot, Daniel; Halwani, Fawaz; Banerjee, Diponkar

2016-01-01

Predictive analytics can provide valuable support to the effective management of pathology facilities. The introduction of new tests and technologies in anatomical pathology will increase the volume of specimens to be processed, as well as the complexity of pathology processes. In order for predictive analytics to address managerial challenges associated with the volume and complexity increases, it is important to pinpoint the areas where pathology managers would most benefit from predictive capabilities. We illustrate common issues in managing pathology facilities with an analysis of the surgical specimen process at the Department of Pathology and Laboratory Medicine (DPLM) at The Ottawa Hospital, which processes all surgical specimens for the Eastern Ontario Regional Laboratory Association. We then show how predictive analytics could be used to support management. Our proposed approach can be generalized beyond the DPLM, contributing to a more effective management of pathology facilities and in turn to quicker clinical diagnoses. PMID:28269873

Containerless processing at high temperatures using acoustic levitation

NASA Technical Reports Server (NTRS)

Rey, C. A.; Merkley, D. R.; Hampton, S.; Devos, J.; Mapes-Riordan, D.; Zatarski, M.

1991-01-01

Advanced techniques are presented which facilitate the development of inert or reducing atmospheres in excess of 2000 K in order to improve processing of containerless capabilities at higher temperatures and to provide more contamination-free environments. Recent testing, in the laboratory and aboard the NASA KC-135 aircraft, of a high-temperature acoustic positioner demonstrated the effectiveness of a specimen motion damping system and of specimen spin control. It is found that stable positioning can be achieved under ambient and heated conditions, including the transient states of heat-up and cool-down. An incorporated high-temperature levitator was found capable of processing specimens of up to 6-mm diameter in a high-purity environment without the contaminating effects of a container at high temperatures and with relative quiescence.

A primer on the cost of quality for improvement of laboratory and pathology specimen processes.

PubMed

Carlson, Richard O; Amirahmadi, Fazlollaah; Hernandez, James S

2012-09-01

In today's environment, many laboratories and pathology practices are challenged to maintain or increase their quality while simultaneously lowering their overall costs. The cost of improving specimen processes is related to quality, and we demonstrate that actual costs can be reduced by designing "quality at the source" into the processes. Various costs are hidden along the total testing process, and we suggest ways to identify opportunities to reduce cost by improving quality in laboratories and pathology practices through the use of Lean, Six Sigma, and industrial engineering.

Quick Reaction Evaluation of Materials and Processes. Delivery Order 0011: Engineering Properties, Fatigue, and Crack Growth Data on SCS-6/Ti-6Al-4V Titanium Matrix Composite (16 Ply) Panels

DTIC Science & Technology

2009-05-01

tabs were bonded to the specimen using a TIG welding process to ensure adhesion of the tabs throughout the experiment. The shear specimens and the...AFRL-RX-WP-TR-2010-4175 QUICK REACTION EVALUATION OF MATERIALS AND PROCESSES Delivery Order 0011: Engineering Properties, Fatigue, and Crack...From - To) May 2009 Final 03 April 2006 – 29 May 2009 4. TITLE AND SUBTITLE QUICK REACTION EVALUATION OF MATERIALS AND PROCESSES Delivery Order

Rapid viscosity measurements of powdered thermosetting resins

NASA Technical Reports Server (NTRS)

Price, H. L.; Burks, H. D.; Dalal, S. K.

1978-01-01

A rapid and inexpensive method of obtaining processing-related data on powdered thermosetting resins has been investigated. The method involved viscosity measurements obtained with a small specimen (less than 100 mg) parallel plate plastometer. A data acquisition and reduction system was developed which provided a value of viscosity and strain rate about 12-13 second intervals during a test. The effects of specimen compaction pressure and reduction of adhesion between specimen and parallel plates were examined. The plastometer was used to measure some processing-related viscosity changes of an addition polyimide resin, including changes caused by pre-test heat treatment, test temperature, and strain rate.

Development of optimum process for electron beam cross-linking of high density polyethylene thermal energy storage pellets, process scale-up and production of application qualities of material

NASA Technical Reports Server (NTRS)

Salyer, I. O.

1980-01-01

The electron irradiation conditions required to prepare thermally from stable high density polyethylene (HDPE) were defined. The conditions were defined by evaluating the heat of fusion and the melting temperature of several HDPE specimens. The performance tests conducted on the specimens, including the thermal cycling tests in the thermal energy storage unit are described. The electron beam irradiation tests performed on the specimens, in which the total radiation dose received by the pellets, the electron beam current, the accelerating potential, and the atmospheres were varied, are discussed.

Study for identification of Beneficial uses of Space (BUS). Volume 3: Appendices

NASA Technical Reports Server (NTRS)

1975-01-01

The quantification of required specimen(s) from space processing experiments, the typical EMI measurements and estimates of a typical RF source, and the integration of commercial payloads into spacelab were considered.

Apparatus for photon activation positron annihilation analysis

DOEpatents

Akers, Douglas W [Idaho Falls, ID

2007-06-12

Non-destructive testing apparatus according to one embodiment of the invention comprises a photon source. The photon source produces photons having predetermined energies and directs the photons toward a specimen being tested. The photons from the photon source result in the creation of positrons within the specimen being tested. A detector positioned adjacent the specimen being tested detects gamma rays produced by annihilation of positrons with electrons. A data processing system operatively associated with the detector produces output data indicative of a lattice characteristic of the specimen being tested.

Effectiveness of Specimen Collection Technology in the Reduction of Collection Turnaround Time and Mislabeled Specimens in Emergency, Medical-Surgical, Critical Care, and Maternal Child Health Departments.

PubMed

Saathoff, April M; MacDonald, Ryan; Krenzischek, Erundina

2018-03-01

The objective of this study was to evaluate the impact of specimen collection technology implementation featuring computerized provider order entry, positive patient identification, bedside specimen label printing, and barcode scanning on the reduction of mislabeled specimens and collection turnaround times in the emergency, medical-surgical, critical care, and maternal child health departments at a community teaching hospital. A quantitative analysis of a nonrandomized, pre-post intervention study design evaluated the statistical significance of reduction of mislabeled specimen percentages and collection turnaround times affected by the implementation of specimen collection technology. Mislabeled specimen percentages in all areas decreased from an average of 0.020% preimplementation to an average of 0.003% postimplementation, with a P < .001. Collection turnaround times longer than 60 minutes decreased after the implementation of specimen collection technology by an average of 27%, with a P < .001. Specimen collection and identification errors are a significant problem in healthcare, contributing to incorrect diagnoses, delayed care, lack of essential treatments, and patient injury or death. Collection errors can also contribute to an increased length of stay, increased healthcare costs, and decreased patient satisfaction. Specimen collection technology has structures in place to prevent collection errors and improve the overall efficiency of the specimen collection process.

Maximizing Modern Distribution of Complex Anatomical Spatial Information: 3D Reconstruction and Rapid Prototype Production of Anatomical Corrosion Casts of Human Specimens

ERIC Educational Resources Information Center

Li, Jianyi; Nie, Lanying; Li, Zeyu; Lin, Lijun; Tang, Lei; Ouyang, Jun

2012-01-01

Anatomical corrosion casts of human specimens are useful teaching aids. However, their use is limited due to ethical dilemmas associated with their production, their lack of perfect reproducibility, and their consumption of original specimens in the process of casting. In this study, new approaches with modern distribution of complex anatomical…

Enclosed Cutting-And-Polishing Apparatus

NASA Technical Reports Server (NTRS)

Rossier, R. N.; Bicknell, B.

1989-01-01

Proposed apparatus cuts and polishes specimens while preventing contamination of outside environment or of subsequent specimens processed in it. Designed for use in zero gravity but also includes features useful in cutting and polishing of toxic or otherwise hazardous materials on Earth. Includes remote manipulator for handling specimens, cutting and polishing wire, inlets for gas and liquid, and outlets for waste liquid and gas. Replaceable plastic liner surrounds working space.

Finite Element Analysis of ECAP, TCAP, RUE and CGP Processes

NASA Astrophysics Data System (ADS)

Patil, Deepak C.; Kallannavar, Vinayak; Bhovi, Prabhakar M.; Kori, S. A.; Venkateswarlu, K.

2016-02-01

A finite element method was applied to study the various severe plastic deformation processes like, Equal Channel Angular Pressing (ECAP), Tubular Channel Angular Pressing (TCAP), Repetitive Upsetting and Extrusion (RUE) and Constrained Groove Pressing (CGP), considering aluminum AA-390 alloy as specimen material for all these processes. FEA simulation was carried out using AFDEX simulation tool. Effect of the various ECAP process parameters like, die corner angle, channel angle, and the coefficient of friction were analyzed. The die corner angles were divided into 2 equal parts for increasing the effectiveness of ECAP process, thereby increasing the channel number from 2 to 3 and further, their influence on ECAP process was investigated. A 3D simulation of TCAP was carried out for die shapes like triangular and trapezoidal, and variation of the generated stress and strain was plotted. In CGP, four cycle operation was carried out; wherein each cycle is composed of corrugating the specimen and subsequent straightening to original dimension. During RUE process, a maximum effective stress of 683.1 MPa was induced in the specimen after processing it for four complete cycles of RUE process; whereas the maximum strain induced during the same condition was 3.715.

Study of amended reports to evaluate and improve surgical pathology processes.

PubMed

Meier, Frederick A; Varney, Ruan C; Zarbo, Richard J

2011-09-01

: Amended surgical pathology reports record defects in the process of transforming tissue specimens into diagnostic information. : Systematic study of amended reports tests 2 hypotheses: (a) that tracking amendment frequencies and the distribution of amendment types reveals relevant aspects of quality in surgical pathology's daily transformation of specimens into diagnoses and (b) that such tracking measures the effect, or lack of effect, of efforts to improve surgical pathology processes. : We applied a binary definition of altered reports as either amendments or addenda and a taxonomy of defects that caused amendments as misidentifications, specimen defects, misinterpretations, and report defects. During the introduction of a LEAN process improvement approach-the Henry Ford Productions System-we followed trends in amendment rates and defect fractions to (a) evaluate specific interventions, (b) sort case-by-case root causes of misidentifications, specimen defects, and misinterpretations, and (c) audit the ongoing accuracy of the classification of changed reports. LEAN is the management and production system of the Toyota Motor Corporation that promotes continuous improvement; it considers wasted resources expended for purposes other than creating value for end customers and targets such expenditures for elimination. : Introduction of real-time editing of amendments saw annual amendment rates increase from 4.8/1000 to 10.1/1000 and then decrease in an incremental manner to 5.6/1000 as Henry Ford Productions System-specific interventions were introduced. Before introduction of HFPS interventions, about a fifth of the amendments were due to misidentifications, a 10th were due to specimen defects, a quarter due to misinterpretation, and almost half were due to report defects. During the period of the initial application of HFPS, the fraction of amendments due to misidentifications decreased as those due to report defects increased, in a statistically linked manner. As HFPS interventions took hold, misidentifications fell from 16% to 9%, specimen defect rates remained variable, ranging between 2% and 11%, and misinterpretations fell from 18% to 3%. Reciprocally, report defects rose from 64% to 83% of all amendment-causing defects. A case-by-case study of misidentifications, specimen defects, and misinterpretations found that (a) intervention at the specimen collection level had disappointingly little effect on patient misidentifications; (b) standardization of specimen accession and gross examination reduced only specimen defects surrounding ancillary testing; but (c) a double review of breast and prostate cases was associated with drastically reduced misinterpretation defects. Finally, audit of both amendments and addenda demonstrated that 10% of the so-called addenda actually qualified as amendments. : Monitored by the consistent taxonomy, rates of amended reports first rose, then fell. Examining specific defect categories provided information for evaluating specific LEAN interventions. Tracking the downward trend of amendment rates seemed to document the overall success of surgical pathology quality improvement efforts. Process improvements modestly decreased fractions of misidentifications and markedly decreased misinterpretation fractions. Classification integrity requires real time, independent editing of both amendments (changed reports) and addenda (addition to reports).

Deducing material quality in cast and hot-forged steels by new bending test

NASA Astrophysics Data System (ADS)

Valberg, Henry; Langøy, Morten; Nedreberg, Mette; Helvig, Torgeir

2017-10-01

A special bend test has been developed and applied for the purpose of characterization and comparison of the material ductility in crankpin steel discs manufactured by casting, or casting subsequently followed by hot open-die forging (ODF) or closed-die forging (CDF). The bending test specimen consists of a small rectangular plate of material with a round hole cut out in the middle. The "eye-shape" specimens were cut out from various positions either near to the surface of, or from the interior of the discs. The test method revealed differences in ductility for the investigated materials, and for different depth positions inside the discs. The roughening of the specimen surface on the top-side of the specimen bend also varied dependent on the processing method for the material. Current results show that this test method is useful for evaluation of material quality in differently processed material. Experimental bend test results are presented for differently processed variants of the same material, i.e., crankpin discs either made by solely casting or casting subsequently followed by hot working either by ODF or CDF.

FluoroSim: A Visual Problem-Solving Environment for Fluorescence Microscopy

PubMed Central

Quammen, Cory W.; Richardson, Alvin C.; Haase, Julian; Harrison, Benjamin D.; Taylor, Russell M.; Bloom, Kerry S.

2010-01-01

Fluorescence microscopy provides a powerful method for localization of structures in biological specimens. However, aspects of the image formation process such as noise and blur from the microscope's point-spread function combine to produce an unintuitive image transformation on the true structure of the fluorescing molecules in the specimen, hindering qualitative and quantitative analysis of even simple structures in unprocessed images. We introduce FluoroSim, an interactive fluorescence microscope simulator that can be used to train scientists who use fluorescence microscopy to understand the artifacts that arise from the image formation process, to determine the appropriateness of fluorescence microscopy as an imaging modality in an experiment, and to test and refine hypotheses of model specimens by comparing the output of the simulator to experimental data. FluoroSim renders synthetic fluorescence images from arbitrary geometric models represented as triangle meshes. We describe three rendering algorithms on graphics processing units for computing the convolution of the specimen model with a microscope's point-spread function and report on their performance. We also discuss several cases where the microscope simulator has been used to solve real problems in biology. PMID:20431698

The use of museum specimens with high-throughput DNA sequencers

PubMed Central

Burrell, Andrew S.; Disotell, Todd R.; Bergey, Christina M.

2015-01-01

Natural history collections have long been used by morphologists, anatomists, and taxonomists to probe the evolutionary process and describe biological diversity. These biological archives also offer great opportunities for genetic research in taxonomy, conservation, systematics, and population biology. They allow assays of past populations, including those of extinct species, giving context to present patterns of genetic variation and direct measures of evolutionary processes. Despite this potential, museum specimens are difficult to work with because natural postmortem processes and preservation methods fragment and damage DNA. These problems have restricted geneticists’ ability to use natural history collections primarily by limiting how much of the genome can be surveyed. Recent advances in DNA sequencing technology, however, have radically changed this, making truly genomic studies from museum specimens possible. We review the opportunities and drawbacks of the use of museum specimens, and suggest how to best execute projects when incorporating such samples. Several high-throughput (HT) sequencing methodologies, including whole genome shotgun sequencing, sequence capture, and restriction digests (demonstrated here), can be used with archived biomaterials. PMID:25532801

Effect of LID (Registered) processing on the microstructure and mechanical properties of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo titanium foil-gauge materials

NASA Technical Reports Server (NTRS)

Balckburn, Linda B.

1987-01-01

A study was undertaken to determine the mechanical properties and microstructures resulting from Liquid Interface Diffusion (LID -Registered) processing of foil-gauge specimens of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo coated with varying amounts of LID material. In addition, the effects of various elevated temperature exposures on the concentration profiles of the LID alloying elements were investigated, using specimens with a narrow strip of LID material applied to the surface. Room and elevated temperature tensile properties were determined for both coated and uncoated specimens. Optical microscopy was used to examine alloy microstructures, and scanning electron microscopy to examine fracture surface morphologies. The chemical concentration profiles of the strip-coated specimens were determined with an electron microprobe.

Producing Zirconium Diboride Components with Complex, Near-Net Shape Geometries by Aqueous Room-Temperature Injection Molding

NASA Technical Reports Server (NTRS)

Wiesner, Valerie L.; Youngblood, Jeffrey; Trice, Rodney

2014-01-01

Room-temperature injection molding is proposed as a novel, low-cost and more energy efficient manufacturing process capable of forming complex-shaped zirconium diboride (ZrB2) parts. This innovative processing method utilized aqueous suspensions with high powder loading and a minimal amount (5 vol.) of water-soluble polyvinylpyrrolidone (PVP), which was used as a viscosity modifier. Rheological characterization was performed to evaluate the room-temperature flow properties of ZrB2-PVP suspensions. ZrB2 specimens were fabricated with high green body strength and were machinable prior to binder removal despite their low polymer content. After binder burnout and pressureless sintering, the bulk density and microstructure of specimens were characterized using Archimedes technique and scanning electron microscopy. X-Ray Diffraction was used to determine the phase compositions present in sintered specimens. Ultimate strength of sintered specimens will be determined using ASTM C1323-10 compressive C-ring test.

Additive Manufacturing of Syntactic Foams: Part 2: Specimen Printing and Mechanical Property Characterization

NASA Astrophysics Data System (ADS)

Singh, Ashish Kumar; Saltonstall, Brooks; Patil, Balu; Hoffmann, Niklas; Doddamani, Mrityunjay; Gupta, Nikhil

2018-03-01

High-density polyethylene (HDPE) and its fly ash cenosphere-filled syntactic foam filaments have been recently developed. These filaments are used for three-dimensional (3D) printing using a commercial printer. The developed syntactic foam filament (HDPE40) contains 40 wt.% cenospheres in the HDPE matrix. Printing parameters for HDPE and HDPE40 were optimized for use in widely available commercial printers, and specimens were three-dimensionally (3D) printed for tensile testing at strain rate of 10-3 s-1. Process optimization resulted in smooth operation of the 3D printer without nozzle clogging or cenosphere fracture during the printing process. Characterization results revealed that the tensile modulus values of 3D-printed HDPE and HDPE40 specimens were higher than those of injection-molded specimens, while the tensile strength was comparable, but the fracture strain and density were lower.

Research on stratified evolution of composite materials under four-point bending loading

NASA Astrophysics Data System (ADS)

Hao, M. J.; You, Q. J.; Zheng, J. C.; Yue, Z.; Xie, Z. P.

2017-12-01

In order to explore the effect of stratified evolution and delamination on the load capacity and service life of the composite materials under the four-point bending loading, the artificial tectonic defects of the different positions were set up. The four-point bending test was carried out, and the whole process was recorded by acoustic emission, and the damage degree of the composite layer was judged by the impact accumulation of the specimen - time-amplitude history chart, load-time-relative energy history chart, acoustic emission impact signal positioning map. The results show that the stratified defects near the surface of the specimen accelerate the process of material failure and expansion. The location of the delamination defects changes the bending performance of the composites to a great extent. The closer the stratification defects are to the surface of the specimen, the greater the damage, the worse the service capacity of the specimen.

Fabrication and Characterization of SMA Hybrid Composites

NASA Technical Reports Server (NTRS)

Turner, Travis L.; Lach, Cynthia L.; Cano, Robert J.

2001-01-01

Results from an effort to fabrication shape memory alloy hybrid composite (SMAHC) test specimens and characterize the material system are presented in this study. The SMAHC specimens are conventional composite structures with an embedded SMA constituent. The fabrication and characterization work was undertaken to better understand the mechanics of the material system, address fabrication issues cited in the literature, and provide specimens for experimental validation of a recently developed thermomechanical model for SMAHC structures. Processes and hardware developed for fabrication of the SMAHC specimens are described. Fabrication of a SMA14C laminate with quasi-isotropic lamination and ribbon-type Nitinol actuators embedded in the 0' layers is presented. Beam specimens are machined from the laminate and are the focus of recent work, but the processes and hardware are readily extensible to more practical structures. Results of thermomechanical property testing on the composite matrix and Nitinol ribbon are presented. Test results from the Nitinol include stress-strain behavior, modulus versus temperature. and constrained recovery stress versus temperature and thermal cycle. Complex thermomechanical behaviors of the Nitinol and composite matrix are demonstrated, which have significant implications for modeling of SMAHC structures.

[Transverse radioulnar branch of the dorsal ulnar nerve: anatomic description and arthroscopic implications from 45 cadaveric dissections].

PubMed

Ehlinger, M; Rapp, E; Cognet, J-M; Clavert, P; Bonnomet, F; Kahn, J-L; Kempf, J-F

2005-05-01

We conducted an anatomic study of the transverse branch of the dorsal ulnar nerve to describe its morphology and position in relation to arthroscopic exploration portals. Forty-five non-side-matched anatomic specimens of unknown age and gender were preserved in formol. The dorsal branch of the ulnar nerve was identified and dissected proximally to distally in order to reveal the different terminal branches. The morphometric analysis included measurement of the length and diameter of the transverse branch and measurement of wrist width. We also measured the smallest distance between the transverse branch and the ulnar styloid process, and between the branch and usual arthroscopic portals (4-5, 6R, 6U) in the axis of the forearm. The transverse branch was inconstant. It was found in 12 of the 45 dissection specimens (27%). In two-thirds of the specimens, the branch ran over less than 50% of the wrist width, tangentially to the radiocarpal joint. Mean nerve diameter was 1 mm. It was found 5-6 mm from the ulnar styloid process and was distal to it in 83% of the specimens. The dissections demonstrated two anatomic variants. Type A corresponded to a branch running distally to the ulnar styloid process, parallel to the joint line (10/12 specimens). Type B exhibited a trajectory proximal to the ulnar styloid process, crossing the ulnar head (2/12 specimens). The relations with the arthroscopic portals (4-5, 6R, 6U) showed that the mean distance from the branch to the portal was 3.75 mm for the 4-5 portal (distally in 11/12 specimens), 3.68 mm for the 6R portal (distally in 10/12 specimens), and 4.83 mm for the 6U portal (distally in 7 specimens and proximally in 5). To our knowledge, there has been only one report specifically devoted to this transverse branch. Two other reports simply mention its existence. According to the literature, the transverse branch of the dorsal ulnar nerve occurs in 60-80% of the cases. We found two anatomic variations different than those described in the literature. Based on our findings and data reported previously, we propose a new classification, describing two main types. In Type 1, the transverse branch arises proximally to the ulnar styloid process;type 1A and type IB are described in relation to the direction of the branch. In Type II, the branch arises distally to the ulnar styloid process;type IIA and type IIB again being described in relation to the direction of the branch. On the tangential trajectory over the radiocarpal joint, the morphometric data show a zone of risk described by a rectangle measuring 10 mm wide (6 mm distal and 4 mm proximal to the ulnar styloid process) and covering 50% of the wrist width. The relations with arthroscopic portals describe a zone of risk corresponding to a 5-7 mm radius circle centered on the portals (4-5, 6R, 6U), which includes 83% of the transverse branches.

Improving the transport of urgent specimens to an off-site laboratory using a novel sticker-tracker.

PubMed

Sepahzad, Afsoon; Ejiofor, Florence; Giles, Susan; Klaber, Robert

2013-01-01

Obtaining results for urgent microbiology specimens in an efficient manner is imperative to ensure that patients receive appropriate antibiotic therapy. A previous audit carried out in the Paediatric department of a central teaching hospital and a number of clinical incidents, highlighted a delay in transport of specimens (exceeding eight hours) and 'missing' specimens. This results in empirical antibiotic treatment of infection, with delay in confirming microbiology result and unnecessary, distressing repeat investigation. As an initial step we sought staff opinion to further explore the problem. A sticker was designed for the microbiology specimen bag to assign accountability, track each step in the transport process and to raise awareness of the problem. The sticker required the member of staff responsible at each stage of the process to time, date and sign it, to allow tracking of potential delays. The new sticker tracking system was promoted and launched in the Paediatric department. Initial challenges included lack of awareness of the protocol and lack of pods for sending urgent specimens. The team met regularly and completed stickers were analysed weekly to identify on-going issues and to devise solutions. Consequently total transport time was reduced to an average of 69 minutes by September (within four hr target). Our intervention improved the efficiency and reliability of urgent specimen transport. This is likely to result in safer antibiotic use and avoid the need for repeat investigation. The system is now also used in the Neonatal department and has lead to the development of a new 'Central Specimens Reception'.

Use of a frameless computed tomography-guided stereotactic biopsy system for nasal biopsy in five dogs.

PubMed

Kuhlman, Gregory M; Taylor, Amanda R; Thieman-Mankin, Kelley M; Griffin, Jay; Cook, Audrey K; Levine, Jonathan M

2016-04-15

5 dogs (median age, 9 years; median body weight, 31 kg [68.2 lb]) with undefined nasal masses were examined after undergoing CT of the head and nasal biopsy via a rostral rhinoscopic or unaided (blind) approach because histologic results for collected biopsy specimens (inflammatory, necrotic, or hemorrhagic disease) suggested the specimens were nonrepresentative of the underlying disease process identified via CT (aggressive or malignant disease). Clinical signs at the time dogs were evaluated included open-mouth breathing, sneezing, or unilateral epistaxis. Histologic findings pertaining to the original biopsy specimens were suggestive of benign processes such as inflammation. In an attempt to obtain better representative specimens, a frameless CT-guided stereotactic biopsy system (CTSBS) was used to collect additional biopsy specimens from masses within the nasal and sinus passages of the dogs. The second set of biopsy specimens was histologically evaluated. Histologic evaluation of biopsy specimens collected via the CTSBS revealed results suggestive of malignant neoplasia (specifically, chondrosarcoma, hemangiopericytoma, or undifferentiated sarcoma) for 3 dogs, mild mixed-cell inflammation for 1 dog, and hamartoma for 1 dog. No complications were reported. These findings resulted in a change in treatment recommendations for 3 dogs and confirmed that no additional treatment was required for 1 dog (with hamartoma). For the remaining dog, in which CT findings and clinical history were strongly suggestive of neoplasia, the final diagnosis was rhinitis. Biopsy specimens were safely collected from masses within the nasal and sinus passages of dogs by use of a frameless CTSBS, allowing a definitive diagnosis that was unachievable with other biopsy approaches.

A dynamic experimental study on the evaporative cooling performance of porous building materials

NASA Astrophysics Data System (ADS)

Zhang, Yu; Zhang, Lei; Meng, Qinglin; Feng, Yanshan; Chen, Yuanrui

2017-08-01

Conventional outdoor dynamic and indoor steady-state experiments have certain limitations in regard to investigating the evaporative cooling performance of porous building materials. The present study investigated the evaporative cooling performance of a porous building material using a special wind tunnel apparatus. First, the composition and control principles of the wind tunnel environment control system were elucidated. Then, the meteorological environment on a typical summer day in Guangzhou was reproduced in the wind tunnel and the evaporation process and thermal parameters of specimens composed of a porous building material were continuously measured. Finally, the experimental results were analysed to evaluate the accuracy of the wind tunnel environment control system, the heat budget of the external surface of the specimens and the total thermal resistance of the specimens and its uncertainty. The analysis results indicated that the normalized root-mean-square error between the measured value of each environmental parameter in the wind tunnel test section and the corresponding value input into the environment control system was <4%, indicating that the wind tunnel apparatus had relatively high accuracy in reproducing outdoor meteorological environments. In addition, the wet specimen could cumulatively consume approximately 80% of the shortwave radiation heat during the day, thereby reducing the temperature of the external surface and the heat flow on the internal surface of the specimen. Compared to the dry specimen, the total thermal resistance of the wet specimen was approximately doubled, indicating that the evaporation process of the porous building material could significantly improve the thermal insulation performance of the specimen.

Potential causes of stage migration and their prognostic implications in colon cancer: a nationwide survey of specialist institutions in Japan.

PubMed

Ueno, Hideki; Hase, Kazuo; Hashiguchi, Yojiro; Shinto, Eiji; Shimazaki, Hideyuki; Yamamoto, Junji; Nakamura, Takahiro; Sugihara, Kenichi

2014-06-01

The actual status of stage migration in colon cancer that occurs in the procedure of preparing pathological specimens of lymph nodes has not been fully investigated. A nationwide survey of specialist institutions for colon cancer treatment was conducted to clarify interinstitutional differences in processing surgical specimens. After categorizing 111 institutions on the basis of their practice of processing specimens, distribution of tumor stage and the recurrence status of 3294 colon cancer patients treated with the same level of lymphadenectomy were compared. Patients were diagnosed with lower tumor stages in non-teaching hospitals, in hospitals where lymph nodes were retrieved by less experienced clinicians and in hospitals in which lymph nodes were retrieved with procedures that preserved the planes of surgery around the primary tumor. However, the process of sectioning and embedding lymph nodes did not affect stage distribution. The average number of lymph nodes examined per case in each institute was 19.4. Institutional number of lymph nodes examined was not associated with node positivity but it did affect the substage in Stage III for number of lymph nodes examined ≥21. In contrast, none of the factors associated with stage migration caused interinstitutional differences in the recurrence status according to the tumor stage. Considerable variety in the processing of surgical specimens existed even within one country, which could be a cause of stage migration in colon cancer. Better awareness of the clinical impact of the lymph node retrieval process is needed; an international guideline to standardize the treatment of surgical specimens might increase the value of tumor staging. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Applying the Principles of Lean Production to Gastrointestinal Biopsy Handling: From the Factory Floor to the Anatomic Pathology Laboratory.

PubMed

Sugianto, Jessica Z; Stewart, Brian; Ambruzs, Josephine M; Arista, Amanda; Park, Jason Y; Cope-Yokoyama, Sandy; Luu, Hung S

2015-01-01

To implement Lean principles to accommodate expanding volumes of gastrointestinal biopsies and to improve laboratory processes overall. Our continuous improvement (kaizen) project analyzed the current state for gastrointestinal biopsy handling using value-stream mapping for specimens obtained at a 487-bed tertiary care pediatric hospital in Dallas, Texas. We identified non-value-added time within the workflow process, from receipt of the specimen in the histology laboratory to the delivery of slides and paperwork to the pathologist. To eliminate non-value-added steps, we implemented the changes depicted in a revised-state value-stream map. Current-state value-stream mapping identified a total specimen processing time of 507 minutes, of which 358 minutes were non-value-added. This translated to a process cycle efficiency of 29%. Implementation of a revised-state value stream resulted in a total process time reduction to 238 minutes, of which 89 minutes were non-value-added, and an improved process cycle efficiency of 63%. Lean production principles of continuous improvement and waste elimination can be successfully implemented within the clinical laboratory.

Apparatus for testing for infection by a retrovirus

DOEpatents

Layne, Scott P.; Beugelsdijk, Tony J.

1999-01-01

An apparatus for testing specimens for infection by a retrovirus is described. The apparatus comprises a process controller including a communications module for translating user commands into test instrument suite commands and a means for communicating specimen test results to a user. The apparatus further comprises a test instrument suite including a means for treating the specimen to manifest an observable result and a detector for measuring the observable result.

Introducing a Virtual Reality Experience in Anatomic Pathology Education.

PubMed

Madrigal, Emilio; Prajapati, Shyam; Hernandez-Prera, Juan C

2016-10-01

A proper examination of surgical specimens is fundamental in anatomic pathology (AP) education. However, the resources available to residents may not always be suitable for efficient skill acquisition. We propose a method to enhance AP education by introducing high-definition videos featuring methods for appropriate specimen handling, viewable on two-dimensional (2D) and stereoscopic three-dimensional (3D) platforms. A stereo camera system recorded the gross processing of commonly encountered specimens. Three edited videos, with instructional audio voiceovers, were experienced by nine junior residents in a crossover study to assess the effects of the exposure (2D vs 3D movie views) on self-reported physiologic symptoms. A questionnaire was used to analyze viewer acceptance. All surveyed residents found the videos beneficial in preparation to examine a new specimen type. Viewer data suggest an improvement in specimen handling confidence and knowledge and enthusiasm toward 3D technology. None of the participants encountered significant motion sickness. Our novel method provides the foundation to create a robust teaching library. AP is inherently a visual discipline, and by building on the strengths of traditional teaching methods, our dynamic approach allows viewers to appreciate the procedural actions involved in specimen processing. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Microfabricated instrument for tissue biopsy and analysis

DOEpatents

Krulevitch, Peter A.; Lee, Abraham P.; Northrup, M. Allen; Benett, William J.

2001-01-01

A microfabricated biopsy/histology instrument which has several advantages over the conventional procedures, including minimal specimen handling, smooth cutting edges with atomic sharpness capable of slicing very thin specimens (approximately 2 .mu.m or greater), micro-liter volumes of chemicals for treating the specimens, low cost, disposable, fabrication process which renders sterile parts, and ease of use. The cutter is a "cheese-grater" style design comprising a block or substrate of silicon and which uses anisotropic etching of the silicon to form extremely sharp and precise cutting edges. As a specimen is cut, it passes through the silicon cutter and lies flat on a piece of glass which is bonded to the cutter. Microchannels are etched into the glass or silicon substrates for delivering small volumes of chemicals for treating the specimen. After treatment, the specimens can be examined through the glass substrate.

Method for on-line evaluation of materials using prompt gamma ray analysis

DOEpatents

Akers, Douglas W [Idaho Falls, ID

2009-12-08

A method for evaluating a material specimen comprises: Mounting a neutron source and a detector adjacent the material specimen; bombarding the material specimen with neutrons from the neutron source to create prompt gamma rays within the material specimen, some of the prompt gamma rays being emitted from the material specimen, some of the prompt gamma rays resulting in the formation of positrons within the material specimen by pair production; collecting positron annihilation data by detecting with the detector at least one emitted annihilation gamma ray resulting from the annihilation of a positron; storing the positron annihilation data on a data storage system for later retrieval and processing; and continuing to collect and store positron annihilation data, the continued collected and stored positron annihilation data being indicative of an accumulation of lattice damage over time.

Measurement of damping of graphite epoxy materials

NASA Technical Reports Server (NTRS)

Crocker, M. J.

1985-01-01

The design of an experiment to measure the damping of a cylindrical graphite-epoxy specimen with a three point support and a knife edge support is described as well as equipment used in tests conducted to determine the influence of the support at the two ends of the specimen and to simulate an idealized free-free boundary condition at the two edges. A curve fitting technique is being used to process the frequency response data obtained. Experiments conducted on the thin plate specimen also reveal the influence of the end support condition on the damping ratio of the specimen. The damping ratio values measured for both specimens appear to be strongly influenced by the shape of the specimen and appear to depend on length and fiber orientation as well as the presence of discontinuities such as sharp bends, corners, and notches.

Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing

NASA Astrophysics Data System (ADS)

Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.; Vance, Eric R.; Amoroso, Jake W.

2018-04-01

Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba1.0Cs0.3Cr1.0Al0.3Fe1.0Ti5.7O16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayed prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed "islands" rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens.

Improved Image-Guided Laparoscopic Prostatectomy

DTIC Science & Technology

2013-07-01

Automatic robotic-assisted palpation has been designed , implemented and tested. Two studies have been completed: 1) ex-vivo prostate specimens using...concerned with the additional processing of the specimens. We responded by designing a phantom box to improve the process so that pathologists could...of the study will be presented below, at task 3a. Task 3. Design and build new LAPUS probe (months 13-24) Data from the ex-vivo

CT Scans of Soil Specimen Processed in Space

NASA Technical Reports Server (NTRS)

1998-01-01

CT scans of the specimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. This view is made from three orthogonal slices. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. (Credit: Los Alamos National Laboratory and the University of Colorado at Boulder).

CT Scans of Soil Specimen Processed in Space

NASA Technical Reports Server (NTRS)

1998-01-01

CT scans of the spcimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. This view depict horizontal slices from top to bottom of a flight specimen. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: Los Alamos National Laboratory and the University of Colorado at Boulder.

Recommendations for gross examination and sampling of surgical specimens of the spleen.

PubMed

O'Malley, Dennis P; Louissaint, Abner; Vasef, Mohammad A; Auerbach, Aaron; Miranda, Roberto; Brynes, Russell K; Fedoriw, Yuri; Hudnall, S David

2015-10-01

This review examines handling and processing of spleen biopsies and splenectomy specimens with the aim of providing the pathologist with guidance in optimizing examination and diagnosis of splenic disorders. It also offers recommendations as to relevant reporting factors in gross examination, which may guide diagnostic workup. The role of splenic needle biopsies is discussed. The International Spleen Consortium is a group dedicated to promoting education and research on the anatomy, physiology, and pathology of the spleen. In keeping with these goals, we have undertaken to provide guidelines for gross examination, sectioning, and sampling of spleen tissue to optimize diagnosis (Burke). The pathology of the spleen may be complicated in routine practice due to a number of factors. Among these are lack of familiarity with lesions, complex histopathology, mimicry within several types of lesions, and overall rarity. To optimize diagnosis, appropriate handling and processing of splenic tissue are crucial. The importance of complete and accurate clinical history cannot be overstated. In many cases, significant clinical history such as previous lymphoproliferative disorders, hematologic disorders, trauma, etc, can provide important information to guide the evaluation of spleen specimens. Clinical information helps plan for appropriate processing of the spleen specimen. The pathologist should encourage surgical colleagues, who typically provide the specimens, to include as much clinical information as possible. Copyright © 2015 Elsevier Inc. All rights reserved.

CT Scans of Soil Specimen Processed in Space

NASA Technical Reports Server (NTRS)

1998-01-01

CT scans of the spcimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. These views depict vertical slices from side to middle of a flight specimen. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: Los Alamos National Laboratory and the University of Colorado at Boulder.

A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: comparison of image quality and diagnostic performance.

PubMed

Ahn, Hye Shin; Kim, Sun Mi; Jang, Mijung; Yun, Bo La; Kim, Bohyoung; Ko, Eun Sook; Han, Boo-Kyung; Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung; Choi, Hye Young

2014-01-01

To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige®), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of "Mammogram enhancement ver. 2.0"; group B (SMB), specimen mammography with application of "Mammogram enhancement ver. 2.0". Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

The stress-corrosion behavior of Al-Li-Cu alloys: A comparison of test methods

NASA Technical Reports Server (NTRS)

Rizzo, P. P.; Galvin, R. P.; Nelson, H. G.

1982-01-01

Two powder metallurgy processed (Al-Li-Cu) alloys with and without Mg addition were studied in aqueous 3.5% NaCl solution during the alternate immersion testing of tuning fork specimens, slow crack growth tests using fracture mechanics specimens, and the slow strain rate testing of straining electrode specimens. Scanning electron microscopy and optical metallography were used to demonstrate the character of the interaction between the Al-Li-Cu alloys and the selected environment. Both alloys are susceptible to SC in an aqueous 3.5% NaCl solution under the right electrochemical and microstructural conditions. Each test method yields important information on the character of the SC behavior. Under all conditions investigated, second phase particles strung out in rows along the extrusion direction in the alloys were rapidly attacked, and played principal role in the SC process. With time, larger pits developed from these rows of smaller pits and under certain electrochemical conditions surface cracks initiated from the larger pits and contributed directly to the fracture process. Evidence to support slow crack growth was observed in both the slow strain rate tests and the sustained immersion tests of precracked fracture mechanics specimens. The possible role of H2 in the stress corrosion cracking process is suggested.

Rapid Identification and Susceptibility Testing of Candida spp. from Positive Blood Cultures by Combination of Direct MALDI-TOF Mass Spectrometry and Direct Inoculation of Vitek 2

PubMed Central

Idelevich, Evgeny A.; Grunewald, Camilla M.; Wüllenweber, Jörg; Becker, Karsten

2014-01-01

Fungaemia is associated with high mortality rates and early appropriate antifungal therapy is essential for patient management. However, classical diagnostic workflow takes up to several days due to the slow growth of yeasts. Therefore, an approach for direct species identification and direct antifungal susceptibility testing (AFST) without prior time-consuming sub-culturing of yeasts from positive blood cultures (BCs) is urgently needed. Yeast cell pellets prepared using Sepsityper kit were used for direct identification by MALDI-TOF mass spectrometry (MS) and for direct inoculation of Vitek 2 AST-YS07 card for AFST. For comparison, MALDI-TOF MS and Vitek 2 testing were performed from yeast subculture. A total of twenty four positive BCs including twelve C. glabrata, nine C. albicans, two C. dubliniensis and one C. krusei isolate were processed. Applying modified thresholds for species identification (score ≥1.5 with two identical consecutive propositions), 62.5% of BCs were identified by direct MALDI-TOF MS. AFST results were generated for 72.7% of BCs directly tested by Vitek 2 and for 100% of standardized suspensions from 24 h cultures. Thus, AFST comparison was possible for 70 isolate-antifungal combinations. Essential agreement (minimum inhibitory concentration difference ≤1 double dilution step) was 88.6%. Very major errors (VMEs) (false-susceptibility), major errors (false-resistance) and minor errors (false categorization involving intermediate result) amounted to 33.3% (of resistant isolates), 1.9% (of susceptible isolates) and 1.4% providing 90.0% categorical agreement. All VMEs were due to fluconazole or voriconazole. This direct method saved on average 23.5 h for identification and 15.1 h for AFST, compared to routine procedures. However, performance for azole susceptibility testing was suboptimal and testing from subculture remains indispensable to validate the direct finding. PMID:25489741

Rapid identification and susceptibility testing of Candida spp. from positive blood cultures by combination of direct MALDI-TOF mass spectrometry and direct inoculation of Vitek 2.

PubMed

Idelevich, Evgeny A; Grunewald, Camilla M; Wüllenweber, Jörg; Becker, Karsten

2014-01-01

Fungaemia is associated with high mortality rates and early appropriate antifungal therapy is essential for patient management. However, classical diagnostic workflow takes up to several days due to the slow growth of yeasts. Therefore, an approach for direct species identification and direct antifungal susceptibility testing (AFST) without prior time-consuming sub-culturing of yeasts from positive blood cultures (BCs) is urgently needed. Yeast cell pellets prepared using Sepsityper kit were used for direct identification by MALDI-TOF mass spectrometry (MS) and for direct inoculation of Vitek 2 AST-YS07 card for AFST. For comparison, MALDI-TOF MS and Vitek 2 testing were performed from yeast subculture. A total of twenty four positive BCs including twelve C. glabrata, nine C. albicans, two C. dubliniensis and one C. krusei isolate were processed. Applying modified thresholds for species identification (score ≥ 1.5 with two identical consecutive propositions), 62.5% of BCs were identified by direct MALDI-TOF MS. AFST results were generated for 72.7% of BCs directly tested by Vitek 2 and for 100% of standardized suspensions from 24 h cultures. Thus, AFST comparison was possible for 70 isolate-antifungal combinations. Essential agreement (minimum inhibitory concentration difference ≤ 1 double dilution step) was 88.6%. Very major errors (VMEs) (false-susceptibility), major errors (false-resistance) and minor errors (false categorization involving intermediate result) amounted to 33.3% (of resistant isolates), 1.9% (of susceptible isolates) and 1.4% providing 90.0% categorical agreement. All VMEs were due to fluconazole or voriconazole. This direct method saved on average 23.5 h for identification and 15.1 h for AFST, compared to routine procedures. However, performance for azole susceptibility testing was suboptimal and testing from subculture remains indispensable to validate the direct finding.

Laser shock peening without coating induced residual stress distribution, wettability characteristics and enhanced pitting corrosion resistance of austenitic stainless steel

NASA Astrophysics Data System (ADS)

Prabhakaran, S.; Kulkarni, Aniket; Vasanth, G.; Kalainathan, S.; Shukla, Pratik; Vasudevan, Vijay K.

2018-01-01

Low energy laser shock peening without coating (LSPwC) was conducted on AISI 304 austenitic stainless steel specimens with varying pulse densities or overlapping. Highest magnitude of compressive residual stress (CRS) was achieved for an optimized pulse density of 2500 pulses/cm2 (75% overlapping). The 2-D and 3-D topographical analysis were indicative of the fact that controlled roughening of the surface was achieved after the LSPwC process. After the LSPwC process, the hydrophilic unpeened surface was converted into the hydrophobic surface, thus decreasing the wettability characteristics of the surface. The X-ray diffraction (XRD) results reveal that there is a beginning of the martensite transformation and the rise in the intensity value of the peaks after LSPwC indicates the presence of compressive residual stresses induced in the specimen. The optical microscope and high-resolution transmission electron microscope results provided evidence of grain refinement and deformation induced refinement features such as multidirectional mechanical twinning, dislocations lines, micro shear cells and stacking faults in the near and sub-surface areas. The average hardness value of the LSPwC specimens was found to be increased by 28% more than the untreated specimen. The potentiodynamic polarization revealed that there was a considerable amount of increase in the pitting corrosion resistance after the LSPwC process, thus, supporting to extend the fatigue life of the specimen. The electrochemical impedance spectroscopic (EIS) analysis depicts that the LSPwC process supports the formation of the strong passivation layer in 3.5% NaCl solution.

Histologic processing and reporting of cutaneous pigmented lesions: recommendations based on a survey of 94 dermatopathologists.

PubMed

Kolman, Olga; Hoang, Mai P; Piris, Adriano; Mihm, Martin C; Duncan, Lyn M

2010-10-01

Standard operating procedures for laboratory processing and reporting of margins of cutaneous pigmented lesions do not exist. We conducted a survey of 94 dermatopathologists to evaluate these practices. We sought to: (1) identify dominant practices among dermatopathologists; (2) determine the impact of the procedure, intent to excise, and histologic diagnosis on the process of margin evaluation; and (3) propose guidelines based on these findings. The survey consisted of 44 questions focused on the impact of procedure (punch, shave, or ellipse), intent (excision or biopsy), and histologic diagnosis (common nevus, congenital nevus, atypical nevus, melanoma) on processing and margin reporting. For ellipses, or specimens indicated as excisions, the majority practice (76%-98%) was to ink the specimens. Although more than 90% of observers report the margins on all melanomas and atypical nevi, fewer than 50% of respondents report margins on all nonatypical nevi. The study consists of a survey sample of dermatopathologists and does not represent the practices of those who did not respond to the survey. Based on the results of this survey we have arrived at the following recommendations: (1) ink all specimens that are ellipses or designated as excisions; (2) tips should be evaluated separately if the specimen is an ellipse; (3) obtain levels in cases with tumor in the tip but not at ink if the specimen is an ellipse or excision and the diagnosis is atypical nevus or melanoma; and (4) report margins on all atypical nevi and melanomas. Copyright © 2009 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Spatiotemporal complexity of 2-D rupture nucleation process observed by direct monitoring during large-scale biaxial rock friction experiments

NASA Astrophysics Data System (ADS)

Fukuyama, Eiichi; Tsuchida, Kotoyo; Kawakata, Hironori; Yamashita, Futoshi; Mizoguchi, Kazuo; Xu, Shiqing

2018-05-01

We were able to successfully capture rupture nucleation processes on a 2-D fault surface during large-scale biaxial friction experiments using metagabbro rock specimens. Several rupture nucleation patterns have been detected by a strain gauge array embedded inside the rock specimens as well as by that installed along the edge walls of the fault. In most cases, the unstable rupture started just after the rupture front touched both ends of the rock specimen (i.e., when rupture front extended to the entire width of the fault). In some cases, rupture initiated at multiple locations and the rupture fronts coalesced to generate unstable ruptures, which could only be detected from the observation inside the rock specimen. Therefore, we need to carefully examine the 2-D nucleation process of the rupture especially when analyzing the data measured only outside the rock specimen. At least the measurements should be done at both sides of the fault to identify the asymmetric rupture propagation on the fault surface, although this is not perfect yet. In the present experiment, we observed three typical types of the 2-D rupture propagation patterns, two of which were initiated at a single location either close to the fault edge or inside the fault. This initiation could be accelerated by the free surface effect at the fault edge. The third one was initiated at multiple locations and had a rupture coalescence at the middle of the fault. These geometrically complicated rupture initiation patterns are important for understanding the earthquake nucleation process in nature.

Recommendations for clinical biomarker specimen preservation and stability assessments.

PubMed

Dakappagari, Naveen; Zhang, Hui; Stephen, Laurie; Amaravadi, Lakshmi; Khan, Masood U

2017-04-01

With the wide use of biomarkers to enable critical drug-development decisions, there is a growing concern from scientific community on the need for a 'standardized process' for ensuring biomarker specimen stability and hence, a strong desire to share best practices on preserving the integrity of biomarker specimens in clinical trials and the design of studies to evaluate analyte stability. By leveraging representative industry experience, we have attempted to provide an overview of critical aspects of biomarker specimen stability commonly encountered during clinical development, including: planning of clinical sample collection procedures, clinical site training, selection of sample preservation buffers, shipping logistics, fit-for-purpose stability assessments in the analytical laboratory and presentation of case studies covering widely utilized biomarker specimen types.

49 CFR 40.161 - What does the MRO do when a drug test specimen is rejected for testing?

Code of Federal Regulations, 2011 CFR

2011-10-01

... negative test is required (e.g., in the case of a pre-employment, return-to-duty, or follow-up test). (c... 49 Transportation 1 2011-10-01 2011-10-01 false What does the MRO do when a drug test specimen is... Verification Process § 40.161 What does the MRO do when a drug test specimen is rejected for testing? As the...

49 CFR 40.161 - What does the MRO do when a drug test specimen is rejected for testing?

Code of Federal Regulations, 2010 CFR

2010-10-01

... negative test is required (e.g., in the case of a pre-employment, return-to-duty, or follow-up test). (c... 49 Transportation 1 2010-10-01 2010-10-01 false What does the MRO do when a drug test specimen is... Verification Process § 40.161 What does the MRO do when a drug test specimen is rejected for testing? As the...

49 CFR 40.161 - What does the MRO do when a drug test specimen is rejected for testing?

Code of Federal Regulations, 2012 CFR

2012-10-01

... negative test is required (e.g., in the case of a pre-employment, return-to-duty, or follow-up test). (c... 49 Transportation 1 2012-10-01 2012-10-01 false What does the MRO do when a drug test specimen is... Verification Process § 40.161 What does the MRO do when a drug test specimen is rejected for testing? As the...

49 CFR 40.161 - What does the MRO do when a drug test specimen is rejected for testing?

Code of Federal Regulations, 2014 CFR

2014-10-01

... negative test is required (e.g., in the case of a pre-employment, return-to-duty, or follow-up test). (c... 49 Transportation 1 2014-10-01 2014-10-01 false What does the MRO do when a drug test specimen is... Verification Process § 40.161 What does the MRO do when a drug test specimen is rejected for testing? As the...

49 CFR 40.161 - What does the MRO do when a drug test specimen is rejected for testing?

Code of Federal Regulations, 2013 CFR

2013-10-01

... negative test is required (e.g., in the case of a pre-employment, return-to-duty, or follow-up test). (c... 49 Transportation 1 2013-10-01 2013-10-01 false What does the MRO do when a drug test specimen is... Verification Process § 40.161 What does the MRO do when a drug test specimen is rejected for testing? As the...

Human Expertise Helps Computer Classify Images

NASA Technical Reports Server (NTRS)

Rorvig, Mark E.

1991-01-01

Two-domain method of computational classification of images requires less computation than other methods for computational recognition, matching, or classification of images or patterns. Does not require explicit computational matching of features, and incorporates human expertise without requiring translation of mental processes of classification into language comprehensible to computer. Conceived to "train" computer to analyze photomicrographs of microscope-slide specimens of leucocytes from human peripheral blood to distinguish between specimens from healthy and specimens from traumatized patients.

Development of a thermally-assisted piercing (TAP) process for introducing holes into thermoplastic composites

NASA Astrophysics Data System (ADS)

Brown, Nicholas W. A.

Composite parts can be manufactured to near-net shape with minimum wastage of material; however, there is almost always a need for further machining. The most common post-manufacture machining operations for composite materials are to create holes for assembly. This thesis presents and discusses a thermally-assisted piercing process that can be used as a technique for introducing holes into thermoplastic composites. The thermally-assisted piercing process heats up, and locally melts, thermoplastic composites to allow material to be displaced around a hole, rather than cutting them out from the structure. This investigation was concerned with how the variation of piercing process parameters (such as the size of the heated area, the temperature of the laminate prior to piercing and the geometry of the piercing spike) changed the material microstructure within carbon fibre/Polyetheretherketone (PEEK) laminates. The variation of process parameters was found to significantly affect the formation of resin rich regions, voids and the fibre volume fraction in the material surrounding the hole. Mechanical testing (using open-hole tension, open-hole compression, plain-pin bearing and bolted bearing tests) showed that the microstructural features created during piercing were having significant influence over the resulting mechanical performance of specimens. By optimising the process parameters strength improvements of up to 11% and 21% were found for pierced specimens when compared with drilled specimens for open-hole tension and compression loading, respectively. For plain-pin and bolted bearing tests, maximum strengths of 77% and 85%, respectively, were achieved when compared with drilled holes. Improvements in first failure force (by 10%) and the stress at 4% hole elongation (by 18%), however, were measured for the bolted bearing tests when compared to drilled specimens. The overall performance of pierced specimens in an industrially relevant application ultimately depends on the properties required for that specific scenario. The results within this thesis show that the piercing technique could be used as a direct replacement to drilling depending on this application.

Infrared thermography for inspecting of pipeline specimen

NASA Astrophysics Data System (ADS)

Chen, Dapeng; Li, Xiaoli; Sun, Zuoming; Zhang, Xiaolong

2018-02-01

Infrared thermography is a fast and effective non-destructive testing method, which has an increasing application in the field of Aeronautics, Astronautic, architecture and medical, et al. Most of the reports about the application of this technology are focus on the specimens of planar, pulse light is often used as the heat stimulation and a plane heat source is generated on the surface of the specimen by the using of a lampshade, however, this method is not suitable for the specimen of non-planar, such as the pipeline. Therefore, in this paper, according the NDT problem of a steel and composite pipeline specimen, ultrasonic and hot water are applied as the heat source respectively, and an IR camera is used to record the temperature varies of the surface of the specimen, defects are revealed by the thermal images sequence processing. Furthermore, the results of light pulse thermography are also shown as comparison, it is indicated that choose the right stimulation method, can get a more effective NDT results for the pipeline specimen.

The effect of disk type and cutting speed on the micro-tensile bond strength of ceramic specimens to resin cement.

PubMed

Castro, Martha C C; Sadek, Fernanda T; Batitucci, Eduardo; Miranda, Mauro S

2014-01-01

The bond strength of dental materials has been evaluated by tensile testing of micro-specimens. The cutting process used to obtain specimens may influence the results. The objective of this study was to investigate the influence of different types of diamond disks and cutting speeds on the bond strength of ceramic specimens and on specimen integrity. Lithium disilicate-based ceramic cubes were bonded with resin cement to composite resin cubes, according to the manufacturers' instructions. The ceramic/cement/resin blocks thus obtained were divided into two groups to be cut with Buehler(®) or Extec(®) disks and then sectioned at cutting speeds of 200 rpm and 400 rpm. The results showed that the bond strength values were affected by the cutting speed and disk/speed interaction (p<0.05). SEM analysis revealed better specimen properties when the blocks were cut at 200 rpm. It was concluded that ceramic specimens must be cut at low speeds.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koohbor, Behrad; Kidane, Addis; Lu, Wei -Yang

Dynamic stress–strain response of rigid closed-cell polymeric foams is investigated in this work by subjecting high toughness polyurethane foam specimens to direct impact with different projectile velocities and quantifying their deformation response with high speed stereo-photography together with 3D digital image correlation. The measured transient displacement field developed in the specimens during high stain rate loading is used to calculate the transient axial acceleration field throughout the specimen. A simple mathematical formulation based on conservation of mass is also proposed to determine the local change of density in the specimen during deformation. By obtaining the full-field acceleration and density distributions,more » the inertia stresses at each point in the specimen are determined through a non-parametric analysis and superimposed on the stress magnitudes measured at specimen ends to obtain the full-field stress distribution. Furthermore, the process outlined above overcomes a major challenge in high strain rate experiments with low impedance polymeric foam specimens, i.e. the delayed equilibrium conditions can be quantified.« less

Detection of Pathogenic Protozoa in the Diagnostic Laboratory: Result Reproducibility, Specimen Pooling, and Competency Assessment▿

PubMed Central

Libman, M. D.; Gyorkos, T. W.; Kokoskin, E.; MacLean, J. D.

2008-01-01

Stool microscopy as performed in clinical parasitology laboratories is a complex procedure with subjective interpretation. Quality assurance (QA) programs often emphasize proficiency testing as an assessment tool. We describe a result reproducibility assessment tool, which can form part of a broader QA program, and which is based on the blinded resubmission of selected clinical samples, using concordance between the reports of the initial and resubmitted specimen as an indicator. Specimens preserved in sodium acetate-acetic acid-formalin can be stored for several months for use in such a program. The presence of multiple protozoa in one specimen does not affect concordance. Some dilution of specimens occurs in this process, and this may explain poor concordance when specimens with low protozoal concentrations are resubmitted. Evaluation of this tool in a large parasitology laboratory revealed concordance rates for pathogenic protozoa (Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Dientamoeba fragilis) of about 80%, which may be considered for use as a benchmark value. We also used this tool to demonstrate that when pairs of specimens from one patient are pooled to create a single specimen, concordance between the results of the individual and pooled specimens is high. PMID:18448690

Improving ED specimen TAT using Lean Six Sigma.

PubMed

Sanders, Janet H; Karr, Tedd

2015-01-01

Lean and Six Sigma are continuous improvement methodologies that have garnered international fame for improving manufacturing and service processes. Increasingly these methodologies are demonstrating their power to also improve healthcare processes. The purpose of this paper is to discuss a case study for the application of Lean and Six Sigma tools in the reduction of turnaround time (TAT) for Emergency Department (ED) specimens. This application of the scientific methodologies uncovered opportunities to improve the entire ED to lab system for the specimens. This case study provides details on the completion of a Lean Six Sigma project in a 1,000 bed tertiary care teaching hospital. Six Sigma's Define, Measure, Analyze, Improve, and Control methodology is very similar to good medical practice: first, relevant information is obtained and assembled; second, a careful and thorough diagnosis is completed; third, a treatment is proposed and implemented; and fourth, checks are made to determine if the treatment was effective. Lean's primary goal is to do more with less work and waste. The Lean methodology was used to identify and eliminate waste through rapid implementation of change. The initial focus of this project was the reduction of turn-around-times for ED specimens. However, the results led to better processes for both the internal and external customers of this and other processes. The project results included: a 50 percent decrease in vials used for testing, a 50 percent decrease in unused or extra specimens, a 90 percent decrease in ED specimens without orders, a 30 percent decrease in complete blood count analysis (CBCA) Median TAT, a 50 percent decrease in CBCA TAT Variation, a 10 percent decrease in Troponin TAT Variation, a 18.2 percent decrease in URPN TAT Variation, and a 2-5 minute decrease in ED registered nurses rainbow draw time. This case study demonstrated how the quantitative power of Six Sigma and the speed of Lean worked in harmony to improve the blood draw process for a 1,000 bed tertiary care teaching hospital. The blood draw process is a standard process used in hospitals to collect blood chemistry and hematology information for clinicians. The methods used in this case study demonstrated valuable and practical applications of process improvement methodologies that can be used for any hospital process and/or service environment. While this is not the first case study that has demonstrated the use of continuous process improvement methodologies to improve a hospital process, it is unique in the way in which it utilizes the strength of the project focussed approach that adheres more to the structure and rigor of Six Sigma and relied less on the speed of lean. Additionally, the application of these methodologies in healthcare is emerging research.

The Effects of Shielded Metal Arc Welding (Smaw) Welding On The Mechanical Characteristics With Heating Treatment inn S45c Steel

NASA Astrophysics Data System (ADS)

Munawar; Abbas, Hammada; Yusran Aminy, Ahmad

2018-02-01

Steel material has been used mainly for making tooling, automotive components, other household needs, power generators to frame buildings and bridges. This study aimed (1) to analyze the mechanical Characteristics of S45C steel with and without heating treatments, and (2) to analyze the temperature of heating treatment which could result in the maximal strength of S45C steel after the welding process. The research was conducted in the laboratory of mechanical engineering study program, Departement of mechanical Engineering, Christian university of indonesia paulus, makassar. The method used materials, instruments, and the dimensions determination of specimen based on the proposed testing standard, Next, was to determine the mechanical caracteristics of the S45C steel wich had been welded and heated.The tensile specimens, the hardness specimen, the impact specimen, and microstructures of which,each of the 3 specimens was the specimens was the specimen without treatment, the spesimen with the welding wthout heating and the specimen of 150°C, 250° C, 300° C. The research results indicated that the treatment process of 150°C, 250°C and 300°C produced the changes of mechanic charateristics with the tensile strength of 42 kgf/mm2 when the temperature had reached 300°C, but at the temperature 300°C, the its toughness would decrease to Hi = 0.836 j/m2 and its hardness would increase to 40.83 at the temperature of 300°C. The value of the maximum strengs was reached at the heating temperature of 300°C for the tensile strength and the hardness, while at the temperature of 300°C its impact value would decrease.

Crack propagation and coalescence due to dual non-penetrating surface flaws and their effect on the strength of rock-like material

NASA Astrophysics Data System (ADS)

Xu, Jun; Zheng, Zheyuan; Xiao, Xiaochun; Li, Zhaoxia

2018-06-01

Non-penetrating surface flaws play a key role in the fracture process of rock-like material, and could cause localized collapse and even failure of the materials. Until now, the mechanism and the effect of surface crack propagation have remained unclear. In this paper, compression tests on gypsum (a soft rock material) are conducted to investigate crack propagation and coalescence due to non-penetrating surface flaws and their effect on the material strength. Specimens are tested under dual pre-existing surface flaws with various combinations of depth and spacing. The results show that when the pre-existing flaws are non-penetrating, the d/t ratio (flaw depth ratio, d is the pre-existing flaw cutting depth and t is the specimen thickness) and the spacing (the distance between the two flaw internal tips) have a strong influence on surface crack patterns and specimen strength. Few cracks emanate from the pre-existing flaws when the flaw depth ratio is equal to 1/3, and more cracks occur with the increase of the flaw depth ratio. When the pre-existing flaw penetrates completely through the specimen, the spacing has a small effect on the specimen strength. A larger flaw depth ratio could advance the occurrence of the peak load (PL) and result in a smaller specimen residual strength. The failure process of the specimen is divided into several stages featured by a stepped decline of the load value after PL, which is closely related to the initiation and propagation of secondary cracks. In addition, the spalling (failure of a portion of the surface caused by coalescence of cracks) can be regarded as indicating the failure of the specimen, and two possible types of spalling formation are briefly discussed.

Improvement of mechanical strength of sintered Mo alloyed steel by optimization of sintering and cold-forging processes with densification

NASA Astrophysics Data System (ADS)

Kamakoshi, Y.; Shohji, I.; Inoue, Y.; Fukuda, S.

2017-10-01

Powder metallurgy (P/M) materials have been expected to be spread in automotive industry. Generally, since sintered materials using P/M ones contain many pores and voids, mechanical properties of them are inferior to those of conventional wrought materials. To improve mechanical properties of the sintered materials, densification is effective. The aim of this study is to improve mechanical strength of sintered Mo-alloyed steel by optimizing conditions in sintering and cold-forging processes. Mo-alloyed steel powder was compacted. Then, pre-sintering (PS) using a vacuum sintering furnace was conducted. Subsequently, coldforging (CF) by a backward extrusion method was conducted to the pre-sintered specimen. Moreover, the cold-forged specimen was heat treated by carburizing, tempering and quenching (CQT). Afterwards, mechanical properties were investigated. As a result, it was found that the density of the PS specimen is required to be more than 7.4 Mg/m3 to strengthen the specimen by heat treatment after CF. Furthermore, density and the microstructure of the PS specimen are most important factors to make the high density and strength material by CF. At the CF load of 1200 kN, the maximum density ratio reached approximately 99% by the use of the PS specimen with proper density and microstructure. At the CF load of 900 kN, although density ratio was high like more than 97.8%, transverse rupture strength decreased sharply. Since densification caused high shear stress and stress concentration in the surface layer, microcracks occurred by the damages of inter-particle sintered connection of the surface layer. On the contrary, in case of the CF load of 1200 kN, ultra-densification of the surface layer occurred by a sufficient plastic flow. Such sufficient compressed specimens regenerated the sintered connections by high temperature heat treatment and thus the high strength densified material was obtained. These processes can be applicable to near net shape manufacturing without surface machining.

The effects of ultrasonic nanocrystal surface modification temperature on the mechanical properties and fretting wear resistance of Inconel 690 alloy

NASA Astrophysics Data System (ADS)

Amanov, A.; Umarov, R.

2018-05-01

In this study, a combination of local heat treatment (LHT) with (w/) and without (w/o) ultrasonic nanocrystal surface modification (UNSM) technique was applied to Inconel 690 alloy at room and high temperatures (RT and HT). The main purpose of this study is to investigate the influence of LHT w/ and w/o UNSM processing on the mechanical and fretting wear mitigation of Inconel 690 alloy. The surface roughness of the specimens was increased with increasing the LHT temperature w/ and w/o UNSM from RT to HT at 700 °C, while the surface hardness of the RT and HT at 300 °C specimens was increased and softening occurred at HT at 700 °C. The mechanical properties of the specimens were investigated using a tensile stress test. It was found that the stress-strain curve of the UNSM-treated at RT exhibited better mechanical characteristics in comparison with the as-received one. Moreover, the specimens treated at HT at 300 and 700 °C exhibited better results in terms of strain, but there was no significant difference in stress. The UNSM treated specimens at HT of 300 °C had better results in comparison with other specimens. In addition, the fretting wear resistance of those specimens was assessed using a ball-on-disk fretting wear tester at temperatures of 25 and 80 °C. The fretting wear resistance of Inconel 690 alloy was also increased by the combination of LHT + UNSM processing, which may be attributed to the increase in mechanical properties, increase in surface roughness, induced compressive residual stress and the presence of a nanostructured surface layer. Hence, Inconel 690 alloy with the increased mechanical properties and fretting wear resistance by the combination of LHT + UNSM processing could be beneficial for nuclear applications.

Fundamental Technical Elements of Freeze-fracture/Freeze-etch in Biological Electron Microscopy

EPA Science Inventory

Freeze-fracture/freeze-etch describes a process whereby specimens, typically biological or nanomaterial in nature, are frozen, fractured, and replicated to generate a carbon/platinum "cast" intended for examination by transmission electron microscopy. Specimens are subjected to u...

Sizing Single Cantilever Beam Specimens for Characterizing Facesheet/Core Peel Debonding in Sandwich Structure

NASA Technical Reports Server (NTRS)

Ratcliffe, James G.

2010-01-01

This paper details part of an effort focused on the development of a standardized facesheet/core peel debonding test procedure. The purpose of the test is to characterize facesheet/core peel in sandwich structure, accomplished through the measurement of the critical strain energy release rate associated with the debonding process. The specific test method selected for the standardized test procedure utilizes a single cantilever beam (SCB) specimen configuration. The objective of the current work is to develop a method for establishing SCB specimen dimensions. This is achieved by imposing specific limitations on specimen dimensions, with the objectives of promoting a linear elastic specimen response, and simplifying the data reduction method required for computing the critical strain energy release rate associated with debonding. The sizing method is also designed to be suitable for incorporation into a standardized test protocol. Preliminary application of the resulting sizing method yields practical specimen dimensions.

Metallurgical and Mechanical Evaluation of 4340 Steel Produced by Direct Metal Laser Sintering

NASA Astrophysics Data System (ADS)

Jelis, Elias; Clemente, Matthew; Kerwien, Stacey; Ravindra, Nuggehalli M.; Hespos, Michael R.

2015-03-01

Direct metal laser sintering (DMLS) was used to produce high-strength low-alloy 4340 steel specimens. Mechanical and metallurgical analyses were performed on the specimens to determine the samples with the highest strengths and the least porosity. The optimal process parameters were thus defined based on the corresponding experimental conditions. Additionally, the effects of fabricating specimens with both virgin and recycled powders were studied. Scanning electron microscopy and electron-dispersive spectroscopy were performed on both types of powders to determine the starting morphology and composition. The initial tensile results are promising, suggesting that DMLS can produce specimens equal in strength to wrought materials. However, there is evidence of cracking on several of the heat-treated tensile specimens that is unexplained. Several theories point to disturbances in the build chamber environment that went undetected while the specimens were being fabricated.

Additive Manufacturing of PLA and CF/PLA Binding Layer Specimens via Fused Deposition Modeling

NASA Astrophysics Data System (ADS)

Li, Yuhang; Gao, Shiyou; Dong, Rongmei; Ding, Xuebing; Duan, Xiaoxi

2018-02-01

As one of the most popular additive manufacturing techniques, fused deposition modeling (FDM) is successfully applied in aerospace, automotive, architecture, and other fields to fabricate thermoplastic parts. Unfortunately, as a result of the limited nature of the mechanical properties and mass in raw materials, there is a pressing need to improve mechanical properties and reduce weight for FDM parts. Therefore, this paper presents an experiment of a special polylactic acid (PLA) and carbon fiber (CF)/PLA-laminated experimental specimen fabricated using the FDM process. The mechanical properties and mass analysis of the new composites for the PLA and CF/PLA binding layer specimen are investigated experimentally. Through the experimental analysis, one can conclude that the mass of laminated specimen is lighter than the CF/PLA specimen, and the tensile and flexural mechanical properties are higher than the pure PLA specimen.

System and method for laser assisted sample transfer to solution for chemical analysis

DOEpatents

Van Berkel, Gary J; Kertesz, Vilmos

2014-01-28

A system and method for laser desorption of an analyte from a specimen and capturing of the analyte in a suspended solvent to form a testing solution are described. The method can include providing a specimen supported by a desorption region of a specimen stage and desorbing an analyte from a target site of the specimen with a laser beam centered at a radiation wavelength (.lamda.). The desorption region is transparent to the radiation wavelength (.lamda.) and the sampling probe and a laser source emitting the laser beam are on opposite sides of a primary surface of the specimen stage. The system can also be arranged where the laser source and the sampling probe are on the same side of a primary surface of the specimen stage. The testing solution can then be analyzed using an analytical instrument or undergo further processing.

Fatigue Behavior of a SiC/SiC Composite at 1000 deg C in Air and in Steam

DTIC Science & Technology

2010-12-01

SiC dual-layer interphase. The composite was manufactured by a Polymer Infiltration and Pyrolysis (PIP... Polymer Infiltration and Pyrolysis (PIP) process. A seal coat of SiC and elemental boron was applied to the test specimens after machining. The tensile...manufactured by a Polymer Infiltration and Pyrolysis (PIP) process. A seal coat of SiC and elemental boron was applied to the test specimens

The effect of tempering treatment on mechanical properties and microstructure for armored lateritic steel

NASA Astrophysics Data System (ADS)

Herbirowo, Satrio; Adjiantoro, Bintang; Romijarso, Toni Bambang; Pramono, Andika Widya

2018-05-01

High demand of armor material impacts on the use of lateritic steel as alternative armored material, therefore an increase of its mechanical properties is necessary. Quenching and tempering process can be used to increase the mechanical properties of the lateritic steel. The variables that used in this research are variation in media quench (water, oil, and air) and variation in tempering temperatures (0, 100, and 200 °C). The results show that specimen with water quenchant tempered at 100 °C have the highest average on hardness (59.1 HRC) and tensile strength. Specimen with oil quenchant tempered at 100 °C has the highest impact toughness (52 J). Secondary hardening and tempered martensite embrittlement phenomenon is found in some specimens where its hardness increased and its impact toughness decreased after the tempering process. Microstructures which formed in this process are martensite and retained austenite phase with fracture types are brittle.

Laser Surface Preparation of Epoxy Composites for Secondary Bonding: Optimization of Ablation Depth

NASA Technical Reports Server (NTRS)

Palmieri, Frank L.; Hopkins, John; Wohl, Christopher J.; Lin, Yi; Connell, John W.; Belcher, Marcus A.; Blohowiak, Kay Y.

2015-01-01

Surface preparation has been identified as one of the most critical aspects of attaining predictable and reliable adhesive bonds. Energetic processes such as laser ablation or plasma treatment are amenable to automation and are easily monitored and adjusted for controlled surface preparation. A laser ablation process was developed to accurately remove a targeted depth of resin, approximately 0.1 to 20 micrometers, from a carbon fiber reinforced epoxy composite surface while simultaneously changing surface chemistry and creating micro-roughness. This work demonstrates the application of this process to prepare composite surfaces for bonding without exposing or damaging fibers on the surface. Composite panels were prepared in an autoclave and had a resin layer approximately 10 micrometers thick above the fiber reinforcement. These composite panels were laser surface treated using several conditions, fabricated into bonded panels and hygrothermally aged. Bond performance of aged, experimental specimens was compared with grit blast surface treated specimens using a modified double cantilever beam test that enabled accelerated saturation of the specimen with water. Comparison of bonded specimens will be used to determine how ablation depth may affect average fracture energies and failure modes.

Torsional rheometer for granular materials slurries and gas-solid mixtures and related methods

DOEpatents

Rajagopal, C.; Rajagopal, K.R.; Yalamanchili, R.C.

1997-03-11

A torsional rheometer apparatus for determining rheological properties of a specimen is provided. A stationary plate and a rotatable plate are in generally coaxial position and structured to receive a specimen there between. In one embodiment, at least one of the plates and preferably both have roughened specimen engaging surfaces to serve to reduce undesired slippage between the plate and the specimen. A motor is provided to rotate the rotatable plate and a transducer for monitoring forces applied to the stationary plate and generating output signals to a computer which determines the desired rheological properties are provided. In one embodiment, the roughened surfaces consist of projections extending toward the specimen. Where granular material is being evaluated, it is preferred that the roughness of the plate is generally equal to the average size of the granular material being processed. In another embodiment, an air-solid mixture is processed and the roughened portions are pore openings in the plates. Air flows through the region between the two pore containing plates to maintain the solid materials in suspension. In yet another embodiment, the base of the stationary plate is provided with a deformable capacitance sensor and associated electronic means. 17 figs.

Torsional rheometer for granular materials slurries and gas-solid mixtures and related methods

DOEpatents

Rajagopal, Chandrika; Rajagopal, Kumbakonam R.; Yalamanchili, Rattaya C.

1997-01-01

A torsional rheometer apparatus for determining rheological properties of a specimen is provided. A stationary plate and a rotatable plate are in generally coaxial position and structured to receive a specimen therebetween. In one embodiment, at least one of the plates and preferably both have roughened specimen engaging surfaces to serve to reduce undesired slippage between the plate and the specimen. A motor is provided to rotate the rotatable plate and a transducer for monitoring forces applied to the stationary plate and generating output signals to a computer which determines the desired rheological properties are provided. In one embodiment, the roughened surfaces consist of projections extending toward the specimen. Where granular material is being evaluated, it is preferred that the roughness of the plate is generally equal to the average size of the granular material being processed. In another embodiment, an air-solid mixture is processed and the roughened portions are pore openings in the plates. Air flows through the region between the two pore containing plates to maintain the solid materials in suspension. In yet another embodiment, the base of the stationary plate is provided with a deformable capacitance sensor and associated electronic means.

Standard operating procedures for serum and plasma collection: early detection research network consensus statement standard operating procedure integration working group.

PubMed

Tuck, Melissa K; Chan, Daniel W; Chia, David; Godwin, Andrew K; Grizzle, William E; Krueger, Karl E; Rom, William; Sanda, Martin; Sorbara, Lynn; Stass, Sanford; Wang, Wendy; Brenner, Dean E

2009-01-01

Specimen collection is an integral component of clinical research. Specimens from subjects with various stages of cancers or other conditions, as well as those without disease, are critical tools in the hunt for biomarkers, predictors, or tests that will detect serious diseases earlier or more readily than currently possible. Analytic methodologies evolve quickly. Access to high-quality specimens, collected and handled in standardized ways that minimize potential bias or confounding factors, is key to the "bench to bedside" aim of translational research. It is essential that standard operating procedures, "the how" of creating the repositories, be defined prospectively when designing clinical trials. Small differences in the processing or handling of a specimen can have dramatic effects in analytical reliability and reproducibility, especially when multiplex methods are used. A representative working group, Standard Operating Procedures Internal Working Group (SOPIWG), comprised of members from across Early Detection Research Network (EDRN) was formed to develop standard operating procedures (SOPs) for various types of specimens collected and managed for our biomarker discovery and validation work. This report presents our consensus on SOPs for the collection, processing, handling, and storage of serum and plasma for biomarker discovery and validation.

System integration and demonstration of adhesive bonded high temperature aluminum alloys for aerospace structure, phase 2

NASA Technical Reports Server (NTRS)

Falcone, Anthony; Laakso, John H.

1993-01-01

Adhesive bonding materials and processes were evaluated for assembly of future high-temperature aluminum alloy structural components such as may be used in high-speed civil transport aircraft and space launch vehicles. A number of candidate high-temperature adhesives were selected and screening tests were conducted using single lap shear specimens. The selected adhesives were then used to bond sandwich (titanium core) test specimens, adhesive toughness test specimens, and isothermally aged lap shear specimens. Moderate-to-high lap shear strengths were obtained from bonded high-temperature aluminum and silicon carbide particulate-reinforced (SiC(sub p)) aluminum specimens. Shear strengths typically exceeded 3500 to 4000 lb/in(sup 2) and flatwise tensile strengths exceeded 750 lb/in(sup 2) even at elevated temperatures (300 F) using a bismaleimide adhesive. All faceskin-to-core bonds displayed excellent tear strength. The existing production phosphoric acid anodize surface preparation process developed at Boeing was used, and gave good performance with all of the aluminum and silicon carbide particulate-reinforced aluminum alloys investigated. The results of this program support using bonded assemblies of high-temperature aluminum components in applications where bonding is often used (e.g., secondary structures and tear stoppers).

Nomenclatural Benchmarking: The roles of digital typification and telemicroscopy

USDA-ARS?s Scientific Manuscript database

The process of nomenclatural benchmarking is the examination of type specimens of all available names to ascertain which currently accepted species the specimen bearing the name falls within. We propose a strategy for addressing four challenges for nomenclatural benchmarking. First, there is the mat...

RNA quality in fresh-frozen gastrointestinal tumor specimens-experiences from the tumor and healthy tissue bank TU Dresden.

PubMed

Zeugner, Silke; Mayr, Thomas; Zietz, Christian; Aust, Daniela E; Baretton, Gustavo B

2015-01-01

The term "pre-analytics" summarizes all procedures concerned with specimen collection or processing as well as logistical aspects like transport or storage of tissue specimens. All or these variables as well as tissue-specific characteristics affect sample quality. While certain parameters like warm ischemia or tissue-specific characteristics cannot be changed, other parameters can be assessed and optimized. The aim of this study was to determine RNA quality by assessing the RIN values of specimens from different organs and to assess the influence of vacuum preservation. Samples from the GI tract, in general, appear to have lower RNA quality when compared to samples from other organ sites. This may be due to the digestive enzymes or bacterial colonization. Processing time in pathology does not significantly influence RNA quality. Tissue preservation with a vacuum sealer leads to preserved RNA quality over an extended period of time and offers a feasible alternative to minimize the influence of transport time into pathology.

A Chemoenzymatic Histology Method for O-GlcNAc Detection.

PubMed

Aguilar, Aime Lopez; Hou, Xiaomeng; Wen, Liuqing; Wang, Peng G; Wu, Peng

2017-12-14

Modification of nuclear and cytoplasmic proteins by the addition or removal of O-GlcNAc dynamically impacts multiple biological processes. Here, we present the development of a chemoenzymatic histology method for the detection of O-GlcNAc in tissue specimens. We applied this method to screen murine organs, uncovering specific O-GlcNAc distribution patterns in different tissue structures. We then utilized our histology method for O-GlcNAc detection in human brain specimens from healthy donors and donors with Alzheimer's disease and found higher levels of O-GlcNAc in specimens from healthy donors. We also performed an analysis using a multiple cancer tissue array, uncovering different O-GlcNAc levels between healthy and cancerous tissues, as well as different O-GlcNAc cellular distributions within certain tissue specimens. This chemoenzymatic histology method therefore holds great potential for revealing the biology of O-GlcNAc in physiopathological processes. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Post-ion beam induced degradation of copper layers in transmission electron microscopy specimens

NASA Astrophysics Data System (ADS)

Seidel, F.; Richard, O.; Bender, H.; Vandervorst, W.

2015-11-01

Copper containing transmission electron microscopy (TEM) specimens frequently show corrosion after focused ion beam (FIB) preparation. This paper reveals that the corrosion product is a Cu-S phase growing over the specimen surface. The layer is identified by energy-dispersive x-ray spectroscopy, and lattice spacing indexing of power spectra patterns. The corrosion process is further studied by TEM on cone-shaped specimens, which are intentionally stored after FIB preparation with S flakes for short time. Furthermore, a protective method against corrosion is developed by varying the time in the FIB vacuum and the duration of a subsequent plasma cleaning.

Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.

Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba 1.0Cs 0.3Cr 1.0Al 0.3Fe 1.0Ti 5.7O 16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayedmore » prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed “islands” rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens.« less

Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing

DOE PAGES

Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.; ...

2018-02-08

Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba 1.0Cs 0.3Cr 1.0Al 0.3Fe 1.0Ti 5.7O 16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayedmore » prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed “islands” rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens.« less

[Automated RNA amplification for the rapid identification of Mycobacterium tuberculosis complex in respiratory specimens].

PubMed

Drouillon, V; Houriez, F; Buze, M; Lagrange, P; Herrmann, J-L

2006-01-01

Rapid and sensitive detection of Mycobacterium tuberculosis complex (MTB) directly on clinical respiratory specimens is essential for a correct management of patients suspected of tuberculosis. For this purpose PCR-based kits are available to detect MTB in respiratory specimen but most of them need at least 4 hours to be completed. New methods, based on TRC method (TRC: Transcription Reverse transcription Concerted--TRCRapid M. Tuberculosis--Tosoh Bioscience, Tokyo, Japon) and dedicated monitor have been developed. A new kit (TRC Rapid M. tuberculosis and Real-time monitor TRCRapid-160, Tosoh Corporation, Japan) enabling one step amplification and real-time detection of MTB 16S rRNA by a combination of intercalative dye oxazole yellow-linked DNA probe and isothermal RNA amplification directly on respiratory specimens has been tested in our laboratory. 319 respiratory specimens were tested in this preliminary study and results were compared to smear and culture. Fourteen had a positive culture for MTB. Among theses samples, smear was positive in 11 cases (78.6%) and TRC process was positive in 8 cases (57.1%). Overall sensitivity of TRC compared to smear positive samples is 73%. Theses first results demonstrated that a rapid identification of MTB was possible (less than 2 processing hours for 14 specimens and about 1 hour for 1 specimen) in most cases of smear positive samples using ready to use reagents for real time detection of MTB rRNA in clinical samples. New pretreatment and extraction reagents kits to increase the stability of the sputum RNA and the extraction efficiency are now tested in our laboratory.

New procedure to reduce the time and cost of broncho-pulmonary specimen management using the Previ Isola® automated inoculation system.

PubMed

Nebbad-Lechani, Biba; Emirian, Aurélie; Maillebuau, Fabienne; Mahjoub, Nadia; Fihman, Vincent; Legrand, Patrick; Decousser, Jean-Winoc

2013-12-01

The microbiological diagnosis of respiratory tract infections requires serial manual dilutions of the clinical specimen before agar plate inoculation, disrupting the workflow in bacteriology clinical laboratories. Automated plating instrument systems have been designed to increase the speed, reproducibility and safety of this inoculating step; nevertheless, data concerning respiratory specimens are lacking. We tested a specific procedure that uses the Previ Isola® (bioMérieux, Craponne, France) to inoculate with broncho-pulmonary specimens (BPS). A total of 350 BPS from a university-affiliated hospital were managed in parallel using the manual reference and the automated methods (expectoration: 75; broncho-alveolar lavage: 68; tracheal aspiration: 17; protected distal sample: 190). A specific enumeration reading grid, a pre-liquefaction step and a fluidity test, performed before the inoculation, were designed for the automated method. The qualitative (i.e., the number of specimens yielding a bacterial count greater than the clinical threshold) and quantitative (i.e., the discrepancy within a 0.5 log value) concordances were 100% and 98.2%, respectively. The slimmest subgroup of expectorations could not be managed by the automated method (8%, 6/75). The technical time and cost savings (i.e., number of consumed plates) reached 50%. Additional studies are required for specific populations, such as cystic fibrosis specimens and associated bacterial variants. An automated decapper should be implemented to increase the biosafety of the process. The PREVI Isola® adapted procedure is a time- and cost-saving method for broncho-pulmonary specimen processing. © 2013.

[Safety management in pathology laboratory: from specimen handling to confirmation of reports].

PubMed

Minato, Hiroshi; Nojima, Takayuki; Nakano, Mariko; Yamazaki, Michiko

2011-03-01

Medical errors in pathological diagnosis give a huge amount of physical and psychological damage to patients as well as medical staffs. We discussed here how to avoid medical errors in surgical pathology laboratory through our experience. Handling of surgical specimens and diagnosing process requires intensive labor and involves many steps. Each hospital reports many kinds of accidents or incidents, however, many laboratories share common problems and each process has its specific risk for the certain error. We analyzed the problems in each process and concentrated on avoiding misaccessioning, mislabeling, and misreporting. We have made several changes in our system, such as barcode labels, digital images of all specimens, putting specimens in embedding cassettes directly on the endoscopic biopsied specimens, and using a multitissue control block as controls in immunohistochemistry. Some problems are still left behind, but we have reduced the errors by decreasing the number of artificial operation as much as possible. A pathological system recognizing the status of read or unread the pathological reports by clinician are now underconstruction. We also discussed about quality assurance of diagnosis, cooperation with clinicians and other comedical staffs, and organization and method. In order to operate riskless work, it is important for all the medical staffs to have common awareness of the problems, keeping careful observations, and sharing all the information in common. Incorporation of an organizational management tool such as ISO 15189 and utilizing PDCA cycle is also helpful for safety management and quality improvement of the laboratory.

The influence of tempering process for DP lateritic steel in hardness and microstructure behavior

NASA Astrophysics Data System (ADS)

Hasbi, Muhammad Yunan; Saefudin, Romijarso, Toni Bambang

2018-05-01

In this study, the influence of tempering temperature on dual phase (DP) steel lateritic has been examined. Lateritic is chosen because of its excellence as austenite stabilizer in the formation of martensite and also increase the weldability due to nickel content. The hardness and microstructure behavior of steels were the main focus of this research. One of the goals was to obtain the combination of high strength and ductile materials for automotive application. The specimens used in this study were low carbon steel made by the hot-rolled process and followed by the initial heating process with various temperature (760 °C, 800 °C, 840 °C) continued with rapid cooling. The specimens also conducted by secondary heating with tempering process at 450 °C in an hour with very slow cooling. The experimental results showed that correlation between temperatures with hardness properties of materials. The hardness of the specimens increases as temperature increases. It was because austenite phase has a sufficient time and temperature to form, therefore the amount of transformed austenite becomes martensite was greater. The highest hardness reached by T = 840 °C was 46.98 HRC, it was about 153% from as cast (18.54 HRC). Decreasing in hardness value when the specimen was tempering at 450 °C indicated that martensite phase has been transformed into tempered martensite.

Dynamic Failure Processes Under Confining Stress in AlON, a Transparent Polycrystalline Ceramic

DTIC Science & Technology

2009-09-01

in a prismatic specimen along one of the three specimen axes, the dynamic loading is imposed (using MKB) along the second specimen axis and the third ...AlON are generally comparable to those of α-Al2O3. Owing to its optically isotropic cubic crystal structure, fully dense, polycrystalline bodies can...illustrated in indentation experiments on Al2O3 [46]) or under tribological loading conditions. During indentation, the region beneath the indenter is

Semiautomated thyroid volumetry using 3D CT: prospective comparison with measurements obtained using 2D ultrasound, 2D CT, and water displacement method of specimen.

PubMed

Lee, Sun Jin; Chong, Semin; Kang, Kyung Ho; Hur, Joonho; Hong, Byung-Woo; Kim, Hyun Jung; Kim, Soo Jin

2014-11-01

The objective of our study was to measure thyroid volumes using semiautomated 3D CT and to compare the 3D CT volumes with volumes measured using 2D ultrasound, 2D CT, and the water displacement method. In 47 patients, 2D ultrasound volumes and 2D CT volumes of the thyroid gland were estimated using the ellipsoid volume formula, and 3D CT volumes were calculated using semiautomated reconstructive techniques. All volume data were compared with thyroid specimen volumes obtained using the water displacement method and were statistically analyzed using the one-way ANOVA, the Pearson correlation coefficient (R), linear regression, and the concordance correlation coefficient (CCC). The processing time of semiautomated 3D CT thyroid volumetry was measured. The paired mean differences ± SD between the three imaging-determined volumes and the specimen volumes were 0.8 ± 3.1 mL for 2D ultrasound, 4.0 ± 4.7 mL for 2D CT, and 0.2 ± 2.5 mL for 3D CT. A significant difference in the mean thyroid volume was found between 2D CT and specimen volumes (p = 0.016) compared with the other pairs (p = 0.937 for 2D ultrasound mean volume vs specimen mean volume, and p = 0.999 for 3D CT mean volume vs specimen mean volume). Between specimen volume and 2D ultrasound volume, specimen volume and 2D CT volume, and specimen volume and 3D CT volume, R values were 0.885, 0.724, and 0.929, respectively, and CCC values were 0.876, 0.598, and 0.925, respectively. The mean processing time of semiautomated 3D CT thyroid volumetry was 7.0 minutes. Thyroid volumes measured using 2D ultrasound or semiautomated 3D CT are substantially close to thyroid specimen volumes measured using the water displacement method. Semiautomated 3D CT thyroid volumetry can provide a more reliable measure of thyroid volume than 2D ultrasound.

Softening due to disordered grain boundaries in nanocrystalline Co.

PubMed

Yuasa, Motohiro; Hakamada, Masataka; Nakano, Hiromi; Mabuchi, Mamoru; Chino, Yasumasa

2013-08-28

Nanocrystalline Co consisting of fcc and hcp phases was processed by electrodeposition, and its mechanical properties were investigated by hardness tests. In addition, high-resolution transmission electron microscopy observations and molecular dynamics (MD) simulations were performed to investigate the grain boundary structure and dislocation nucleation from the grain boundaries. A large amount of disorders existed at the grain boundaries and stacking faults were formed from the grain boundaries in the as-deposited Co specimen. The as-deposited specimen showed a lower hardness than did the annealed specimen, although the grain size of the former was smaller than that of the latter. The activation volume of the as-deposited specimen (=1.5b(3)) was lower than that of the annealed specimen (=50b(3)), thus indicating that nucleation of dislocations from grain boundaries is more active in the as-deposited specimen than in the annealed specimens. The MD simulations showed that dislocation nucleation was closely related to a change in the defect structures at the boundary. Therefore, it is suggested that a significant amount of defects enhance changes in the defect structures at the boundary, resulting in softening of the as-deposited specimen.

Softening due to disordered grain boundaries in nanocrystalline Co

NASA Astrophysics Data System (ADS)

Yuasa, Motohiro; Hakamada, Masataka; Nakano, Hiromi; Mabuchi, Mamoru; Chino, Yasumasa

2013-08-01

Nanocrystalline Co consisting of fcc and hcp phases was processed by electrodeposition, and its mechanical properties were investigated by hardness tests. In addition, high-resolution transmission electron microscopy observations and molecular dynamics (MD) simulations were performed to investigate the grain boundary structure and dislocation nucleation from the grain boundaries. A large amount of disorders existed at the grain boundaries and stacking faults were formed from the grain boundaries in the as-deposited Co specimen. The as-deposited specimen showed a lower hardness than did the annealed specimen, although the grain size of the former was smaller than that of the latter. The activation volume of the as-deposited specimen (=1.5b3) was lower than that of the annealed specimen (=50b3), thus indicating that nucleation of dislocations from grain boundaries is more active in the as-deposited specimen than in the annealed specimens. The MD simulations showed that dislocation nucleation was closely related to a change in the defect structures at the boundary. Therefore, it is suggested that a significant amount of defects enhance changes in the defect structures at the boundary, resulting in softening of the as-deposited specimen.

Detection, mapping, and quantification of single walled carbon nanotubes in histological specimens with photoacoustic microscopy.

PubMed

Avti, Pramod K; Hu, Song; Favazza, Christopher; Mikos, Antonios G; Jansen, John A; Shroyer, Kenneth R; Wang, Lihong V; Sitharaman, Balaji

2012-01-01

In the present study, the efficacy of multi-scale photoacoustic microscopy (PAM) was investigated to detect, map, and quantify trace amounts [nanograms (ng) to micrograms (µg)] of SWCNTs in a variety of histological tissue specimens consisting of cancer and benign tissue biopsies (histological specimens from implanted tissue engineering scaffolds). Optical-resolution (OR) and acoustic-resolution (AR)--Photoacoustic microscopy (PAM) was employed to detect, map and quantify the SWCNTs in a variety of tissue histological specimens and compared with other optical techniques (bright-field optical microscopy, Raman microscopy, near infrared (NIR) fluorescence microscopy). Both optical-resolution and acoustic-resolution PAM, allow the detection and quantification of SWCNTs in histological specimens with scalable spatial resolution and depth penetration. The noise-equivalent detection sensitivity to SWCNTs in the specimens was calculated to be as low as ∼7 pg. Image processing analysis further allowed the mapping, distribution, and quantification of the SWCNTs in the histological sections. The results demonstrate the potential of PAM as a promising imaging technique to detect, map, and quantify SWCNTs in histological specimens, and could complement the capabilities of current optical and electron microscopy techniques in the analysis of histological specimens containing SWCNTs.

A study of process parameters on workpiece anisotropy in the laser engineered net shaping (LENSTM) process

NASA Astrophysics Data System (ADS)

Chandra, Shubham; Rao, Balkrishna C.

2017-06-01

The process of laser engineered net shaping (LENSTM) is an additive manufacturing technique that employs the coaxial flow of metallic powders with a high-power laser to form a melt pool and the subsequent deposition of the specimen on a substrate. Although research done over the past decade on the LENSTM processing of alloys of steel, titanium, nickel and other metallic materials typically reports superior mechanical properties in as-deposited specimens, when compared to the bulk material, there is anisotropy in the mechanical properties of the melt deposit. The current study involves the development of a numerical model of the LENSTM process, using the principles of computational fluid dynamics (CFD), and the subsequent prediction of the volume fraction of equiaxed grains to predict process parameters required for the deposition of workpieces with isotropy in their properties. The numerical simulation is carried out on ANSYS-Fluent, whose data on thermal gradient are used to determine the volume fraction of the equiaxed grains present in the deposited specimen. This study has been validated against earlier efforts on the experimental studies of LENSTM for alloys of nickel. Besides being applicable to the wider family of metals and alloys, the results of this study will also facilitate effective process design to improve both product quality and productivity.

Clinical and Analytical Evaluation of a Single-Vial Stool Collection Device with Formalin-Free Fixative for Improved Processing and Comprehensive Detection of Gastrointestinal Parasites

PubMed Central

Couturier, Brianne A.; Jensen, Ryan; Arias, Nora; Heffron, Michael; Gubler, Elyse; Case, Kristin; Gowans, Jason

2015-01-01

Microscopic examination of feces is a standard laboratory method for diagnosing gastrointestinal parasite infections. In North America, the ovum and parasite (O&P) examination is typically performed using stool that is chemically fixed in polyvinyl alcohol (PVA) and formalin, after which the stool is concentrated by filtration to enhance sensitivity. Mini Parasep solvent-free (SF) tubes allow collection and concentration within a single collection vial. The goal of the study was to determine whether consolidated processing and concentration with the Parasep tubes using an alcohol-based fixative (Alcorfix) provide O&P examinations equivalent to or better than those done by processing of PVA-formalin-fixed stool using a SpinCon concentration device. Parasep tubes revealed filtration performance equivalent to that of the SpinCon concentration device using PVA-formalin-fixed stool containing protozoa. Specimens cocollected in Parasep tubes containing PVA-formalin and Alcorfix revealed comparable morphology and staining for various protozoa. Alcorfix effectively fixed live Cryptosporidium and microsporidia such that morphology and staining were conserved for modified acid-fast and modified trichrome stains. A work flow analysis revealed significant time savings for batches of 10 or 30 O&P specimens in tubes with Alcorfix compared to the amount of time that it took to analyze the same number of specimens in tubes with PVA-formalin. The direct hands-on time savings with Mini Parasep tubes were 17 min and 41 s and 32 min and 1 s for batches of 10 and 30 specimens, respectively. Parasep tubes containing Alcorfix provide significant work flow advantages to laboratories that process medium to high volumes of O&P specimens by streamlining processing and converting to a single tube. These improvements in work flow, reduction of the amount of formalin used in the laboratory, and equivalent microscopy results are attractive advancements in O&P testing for North American diagnostic parasitology laboratories. PMID:26019199

Clinical and Analytical Evaluation of a Single-Vial Stool Collection Device with Formalin-Free Fixative for Improved Processing and Comprehensive Detection of Gastrointestinal Parasites.

PubMed

Couturier, Brianne A; Jensen, Ryan; Arias, Nora; Heffron, Michael; Gubler, Elyse; Case, Kristin; Gowans, Jason; Couturier, Marc Roger

2015-08-01

Microscopic examination of feces is a standard laboratory method for diagnosing gastrointestinal parasite infections. In North America, the ovum and parasite (O&P) examination is typically performed using stool that is chemically fixed in polyvinyl alcohol (PVA) and formalin, after which the stool is concentrated by filtration to enhance sensitivity. Mini Parasep solvent-free (SF) tubes allow collection and concentration within a single collection vial. The goal of the study was to determine whether consolidated processing and concentration with the Parasep tubes using an alcohol-based fixative (Alcorfix) provide O&P examinations equivalent to or better than those done by processing of PVA-formalin-fixed stool using a SpinCon concentration device. Parasep tubes revealed filtration performance equivalent to that of the SpinCon concentration device using PVA-formalin-fixed stool containing protozoa. Specimens cocollected in Parasep tubes containing PVA-formalin and Alcorfix revealed comparable morphology and staining for various protozoa. Alcorfix effectively fixed live Cryptosporidium and microsporidia such that morphology and staining were conserved for modified acid-fast and modified trichrome stains. A work flow analysis revealed significant time savings for batches of 10 or 30 O&P specimens in tubes with Alcorfix compared to the amount of time that it took to analyze the same number of specimens in tubes with PVA-formalin. The direct hands-on time savings with Mini Parasep tubes were 17 min and 41 s and 32 min and 1 s for batches of 10 and 30 specimens, respectively. Parasep tubes containing Alcorfix provide significant work flow advantages to laboratories that process medium to high volumes of O&P specimens by streamlining processing and converting to a single tube. These improvements in work flow, reduction of the amount of formalin used in the laboratory, and equivalent microscopy results are attractive advancements in O&P testing for North American diagnostic parasitology laboratories. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Three-Dimensional Numerical Simulation on Triaxial Failure Mechanical Behavior of Rock-Like Specimen Containing Two Unparallel Fissures

NASA Astrophysics Data System (ADS)

Huang, Yan-Hua; Yang, Sheng-Qi; Zhao, Jian

2016-12-01

A three-dimensional particle flow code (PFC3D) was used for a systematic numerical simulation of the strength failure and cracking behavior of rock-like material specimens containing two unparallel fissures under conventional triaxial compression. The micro-parameters of the parallel bond model were first calibrated using the laboratory results of intact specimens and then validated from the experimental results of pre-fissured specimens under triaxial compression. Numerically simulated stress-strain curves, strength and deformation parameters and macro-failure modes of pre-fissured specimens were all in good agreement with the experimental results. The relationship between stress and the micro-crack numbers was summarized. Crack initiation, propagation and coalescence process of pre-fissured specimens were analyzed in detail. Finally, horizontal and vertical cross sections of numerical specimens were derived from PFC3D. A detailed analysis to reveal the internal damage behavior of rock under triaxial compression was carried out. The experimental and simulated results are expected to improve the understanding of the strength failure and cracking behavior of fractured rock under triaxial compression.

Cytotoxicity Test and Mass Spectrometry of IPMC

NASA Astrophysics Data System (ADS)

Takashima, Kazuto; Kamamichi, Norihiro; Yagi, Tohru; Asaka, Kinji; Mukai, Toshiharu

Ionic polymer-metal composite (IPMC) is a promising material in biomedical actuators and sensors because IPMC is soft and flexible, leading to the safety of the device itself. The purpose of this study is to investigate the biocompatibility of IPMC by in vitro experiments, in order to evaluate the applicability in biomedical fields. In addition to an IPMC specimen prepared by the conventional “impregnation-reduction method” using cationic gold complexes and reducing agents, two specimens were prepared by processes in addition to that used for the conventional IPMC specimen. One specimen was reduced in Na2SO3 solution and another specimen was cleaned in H2O2 solution. Colony-forming test using Chinese hamster V79 cells shows high cytotoxicity of all IPMC specimens. Examination of direct inlet mass spectrometry (DI-MS) revealed that the peak intensity of gold complex (particularly, m/z=180) was different from that of Nafion film. Monitoring the peak at m/z=180 showed a remnant with the structure of phenanthroline in IPMC specimens which were not cleaned in H2O2 solution.

Microfabricated instrument for tissue biopsy and analysis

DOEpatents

Krulevitch, Peter A.; Lee, Abraham P.; Northrup, M. Allen; Benett, William J.

1999-01-01

A microfabricated biopsy/histology instrument which has several advantages over the conventional procedures, including minimal specimen handling, smooth cutting edges with atomic sharpness capable of slicing very thin specimens (approximately 2 .mu.m or greater), micro-liter volumes of chemicals for treating the specimens, low cost, disposable, fabrication process which renders sterile parts, and ease of use. The cutter is a "cheese-grater" style design comprising a block or substrate of silicon and which uses anisotropic etching of the silicon to form extremely sharp and precise cutting edges. As a specimen is cut, it passes through the silicon cutter and lies flat on a piece of glass which is bonded to the cutter. Microchannels are etched into the glass or silicon substrates for delivering small volumes of chemicals for treating the specimen. After treatment, the specimens can be examined through the glass substrate. For automation purposes, microvalves and micropumps may be incorporated. Also, specimens in parallel may be cut and treated with identical or varied chemicals. The instrument is disposable due to its low cost and thus could replace current expensive microtome and histology equipment.

Dynamic fracture of sintered Nd-Fe-B magnet under uniaxial compression

NASA Astrophysics Data System (ADS)

Wang, Huanran; Wan, Yin; Chen, Danian; Lei, Guohua; Ren, Chunying

2018-06-01

The dynamic fracture of the Nd-Fe-B magnets under uniaxial compression is investigated using a split Hopkinson pressure bar (SHPB). The surface deformation and fracture processes of the Nd-Fe-B specimens are recorded adopting a high-speed photography (HSP) with digital image correlation (DIC). The load and work applied to the specimens in the SHPB tests are determined with the strain signals of the transmitted and reflected waves. The surface strain distributions of the Nd-Fe-B specimen during the SHPB testing are revealed with DIC. It is shown by the HSP with DIC that when the load is near the maximum, the cracks at some positions on the surface of the expanding Nd-Fe-B specimen are formed and ran along certain directions. The work applied to the specimen per unit volume which corresponds to the maximal load is used to characterize the impact stability of the Nd-Fe-B specimen. The localized fracture strains at some positions on the surface of the expanding specimens at some characteristic times are determined with DIC, which are the projections of the strains onto the DIC plane.

Investigation of the dynamic stress–strain response of compressible polymeric foam using a non-parametric analysis

DOE PAGES

Koohbor, Behrad; Kidane, Addis; Lu, Wei -Yang; ...

2016-01-25

Dynamic stress–strain response of rigid closed-cell polymeric foams is investigated in this work by subjecting high toughness polyurethane foam specimens to direct impact with different projectile velocities and quantifying their deformation response with high speed stereo-photography together with 3D digital image correlation. The measured transient displacement field developed in the specimens during high stain rate loading is used to calculate the transient axial acceleration field throughout the specimen. A simple mathematical formulation based on conservation of mass is also proposed to determine the local change of density in the specimen during deformation. By obtaining the full-field acceleration and density distributions,more » the inertia stresses at each point in the specimen are determined through a non-parametric analysis and superimposed on the stress magnitudes measured at specimen ends to obtain the full-field stress distribution. Furthermore, the process outlined above overcomes a major challenge in high strain rate experiments with low impedance polymeric foam specimens, i.e. the delayed equilibrium conditions can be quantified.« less

Woven graphite epoxy composite test specimens with glass buffer strips

NASA Technical Reports Server (NTRS)

Bonnar, G. R.; Palmer, R. J.

1982-01-01

Woven unidirectional graphite cloth with bands of fiberglass replacing the graphite in discrete lengthwise locations was impregnated with epoxy resin and used to fabricate a series of composite tensile and shear specimens. The finished panels, with the fiberglass buffer strips, were tested. Details of the fabrication process are reported.

37 CFR 1.94 - Return of models, exhibits or specimens.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES National Processing Provisions Models... business before the Office and will be returned, applicant must arrange for the return of the model... model, exhibit or specimen is no longer necessary for the conduct of business before the Office. (b...

Collection & Processing of Vertebrate Specimens for Arbovirus Studies.

ERIC Educational Resources Information Center

Sudia, W. Daniel; And Others

Described are techniques used by the National Communicable Disease Center in obtaining blood and tissues from man and other vertebrates for arbovirus isolation and antibody studies. Also included are techniques for capturing and handling vertebrates; banding and marking; restraining and bleeding; storing of specimens to preserve antibody and…

Compliance of clinical microbiology laboratories in the United States with current recommendations for processing respiratory tract specimens from patients with cystic fibrosis.

PubMed

Zhou, Juyan; Garber, Elizabeth; Desai, Manisha; Saiman, Lisa

2006-04-01

Respiratory tract specimens from patients with cystic fibrosis (CF) require unique processing by clinical microbiology laboratories to ensure detection of all potential pathogens. The present study sought to determine the compliance of microbiology laboratories in the United States with recently published recommendations for CF respiratory specimens. Microbiology laboratory protocols from 150 of 190 (79%) CF care sites were reviewed. Most described the use of selective media for Burkholderia cepacia complex (99%), Staphylococcus aureus (82%), and Haemophilus influenzae (89%) and identified the species of all gram-negative bacilli (87%). Only 52% delineated the use of agar diffusion assays for susceptibility testing of Pseudomonas aeruginosa. Standardizing laboratory practices will improve treatment, infection control, and our understanding of the changing epidemiology of CF microbiology.

Test of superplastically formed corrugated aluminum compression specimens with beaded webs

NASA Technical Reports Server (NTRS)

Davis, Randall C.; Royster, Dick M.; Bales, Thomas T.; James, William F.; Shinn, Joseph M., Jr.

1991-01-01

Corrugated wall sections provide a highly efficient structure for carrying compressive loads in aircraft and spacecraft fuselages. The superplastic forming (SPF) process offers a means to produce complex shells and panels with corrugated wall shapes. A study was made to investigate the feasibility of superplastically forming 7475-T6 aluminum sheet into a corrugated wall configuration and to demonstrate the structural integrity of the construction by testing. The corrugated configuration selected has beaded web segments separating curved-cap segments. Eight test specimens were fabricated. Two specimens were simply a single sheet of aluminum superplastically formed to a beaded-web, curved-cap corrugation configuration. Six specimens were single-sheet corrugations modified by adhesive bonding additional sheet material to selectively reinforce the curved-cap portion of the corrugation. The specimens were tested to failure by crippling in end compression at room temperature.

Charpy Impact Energy and Microindentation Hardness of 60-NITINOL

NASA Technical Reports Server (NTRS)

Stanford, Malcolm K.

2012-01-01

60-NITINOL (60 wt.% Ni 40 wt.% Ti) is being studied as a material for advanced aerospace components. The Charpy impact energy and microindentation hardness has been studied for this material, fabricated by vacuum induction skull melting (casting) and by hot isostatic pressing. Test specimens were prepared in various hardened and annealed heat treatment conditions. The average impact energy ranged from 0.33 to 0.49J for the hardened specimens while the annealed specimens had impact energies ranging from 0.89 to 1.18J. The average hardness values of the hardened specimens ranged from 590 to 676 HV while that of the annealed specimens ranged from 298 to 366 HV, suggesting an inverse relationship between impact energy and hardness. These results are expected to provide guidance in the selection of heat treatment processes for the design of mechanical components.

X-ray microanalysis in the scanning electron microscope.

PubMed

Roomans, Godfried M; Dragomir, Anca

2014-01-01

X-ray microanalysis conducted using the scanning electron microscope is a technique that allows the determination of chemical elements in bulk or semi-thick specimens. The lowest concentration of an element that can be detected is in the order of a few mmol/kg or a few hundred parts per million, and the smallest amount is in the order of 10(-18) g. The spatial resolution of the analysis depends on the thickness of the specimen. For biological specimen analysis, care must be taken to prevent displacement/loss of the element of interest (usually ions). Protocols are presented for the processing of frozen-hydrated and freeze-dried specimens, as well as for the analysis of small volumes of fluid, cell cultures, and other specimens. Aspects of qualitative and quantitative analysis are covered, including limitations of the technique.

X-ray microanalysis in the scanning electron microscope.

PubMed

Roomans, Godfried M; Dragomir, Anca

2007-01-01

X-ray microanalysis conducted using the scanning electron microscope is a technique that allows the determination of chemical elements in bulk or semithick specimens. The lowest concentration of an element that can be detected is in the order of a few mmol/kg or a few hundred parts per million, and the smallest amount is in the order of 10(-18) g. The spatial resolution of the analysis depends on the thickness of the specimen. For biological specimen analysis, care must be taken to prevent displacement/loss of the element of interest (usually ions). Protocols are presented for the processing of frozen-hydrated and freeze-dried specimens, as well as for the analysis of small volumes of fluid, cell cultures and other specimens. Aspects of qualitative and quantitative analysis are covered, including limitations of the technique.

Dry sliding wear system response of ferritic and tempered martensitic ductile iron

NASA Astrophysics Data System (ADS)

Jha, V. K.; Mozumder, Y. H.; Shama, S.; Behera, R. K.; Pattaniak, A.; P, Sindhoora L.; Mishra, S. C.; Sen, S.

2015-02-01

Spheroidal graphite cast iron (SG iron) is the most preferable member of cast iron family due to its strength and toughness along with good tribological properties. SG iron specimens with annealed and martensitic matrix were subjected to dry sliding wear condition and the system response was correlated to matrix microstructure. Respective microstructure was obtained by annealing and quench and tempering heat treatment process for an austenitizing temperature of 1000°C. Specimens were subjected to Ball on plate wear tester under 40N, 50N, 60N load for a sliding distance of 7.54m. Except for quench and tempered specimen at 50N, weight loss was observed in every condition. The wear surface under optical microscope reveals adhesive mechanism for as-cast and annealed specimen whereas delaminated wear track feature was observed for quench and tempered specimen.

Bonding and nondestructive evaluation of graphite/PEEK composite and titanium adherends with thermoplastic adhesives

NASA Technical Reports Server (NTRS)

Hodges, W. T.; Tyeryar, J. R.; Berry, M.

1985-01-01

Bonded single overlap shear specimens were fabricated from Graphite/PEEK (Polyetheretherketone) composite adherends and titanium adherends. Six advanced thermoplastic adhesives were used for the bonding. The specimens were bonded by an electromagnetic induction technique producing high heating rates and high-strength bonds in a few minutes. This contrasts with conventionally heated presses or autoclaves that take hours to process comparable quality bonds. The Graphite/PEEK composites were highly resistant to delamination during the testing. This allowed the specimen to fail exclusively through the bondline, even at very high shear loads. Nondestructive evaluation of bonded specimens was performed ultrasonically by energizing the entire thickness of the material through the bondline and measuring acoustic impedance parameters. Destructive testing confirmed the unique ultrasonic profiles of strong and weak bonds, establishing a standard for predicting relative bond strength in subsequent specimens.

Microhardness, Friction and Wear of SiC and Si3N4 Materials as a Function of Load, Temperature and Environment.

DTIC Science & Technology

1981-10-01

microstructures which may be developed and finally to relate properties to structure and composition (28-31). Sialon materials are alloys of Si3N4 with oxides...techniques. The effects of specimen microstructure on indentation processes were determined by using materials formed by a wide range of fabrication...microhardness techniques. The effects of specimen microstructure on indentation processes were determined by using materials formed by a wide range of

The effect of processing on autohesive strength development in thermoplastic resins and composites

NASA Technical Reports Server (NTRS)

Howes, Jeremy C.; Loos, Alfred C.; Hinkley, Jeffrey A.

1989-01-01

In the present investigation of processing effects on the autohesive bond strength of neat polysulfone resin and graphite-reinforced polysulfone-matrix composites measured resin bond strength development in precracked compact tension specimens 'healed' by heating over a contact period at a given temperature. The critical strain energy release rate of refractured composite specimens did not exhibit the strong time or temperature dependence of the neat resin tests; only 80-90 percent of the undamaged fracture energy is recoverable.

[Monitoring of methyl methacrylate monomer released from autopolymerized denture base polymers during processing using time-of-flight mass spectrometer].

PubMed

Ma, Yu-juan; Cui, Hua-peng; Li, Hai-yang

2011-04-01

To analyze the amount and tendency of methyl methacrylate (MMA) released from autopolymerized denture base polymer (self-curing resin) during processing using time-of-flight mass spectrometer (TOF-MS). Self-curing resin was mixed in the container using a ratio of 2 g of powder to 1 g of liquid in accordance with the manufacturer's instructions for 40 s as a specimen. The amount of MMA released from the specimen was continuously monitored and simultaneously recorded every minute by TOF-MS since immediately after mixing. A total of five specimens were monitored. The amount of MMA increased dramatically at 11 min [(45.2 ± 3.5) mg/L] after mixing, and reached the highest level at 13 min [(228.9 ± 22.6) mg/L], then become stable at 23 min [(8.8 ± 2.3) mg/L] after mixing. The releasing tendency of MMA could be analyzed accurately with continuously monitoring during processing. The amount of MMA released from self-curing resin changed rapidly and the processing was complicated and changeful.

Titanium Nitride: An Oxidizable Coating for the High-Temperature Protection of Graphite

NASA Technical Reports Server (NTRS)

Wakelyn, N. T.

1961-01-01

A titanium nitride coating for graphite, prepared by deposition process, protected test specimens for 60 seconds the vapors in a supersonic ceramic-heated air jet with a stagnation temperature of approximately 2,250 K. For the same test conditions, coated specimens showed no damage to the graphite body for the 60-second test, whereas uncoated specimens were very severely damaged after 20 seconds and were destroyed toward the end of the test. A discussion of the coating of these graphite specimens and of some of the conditions necessary for the utilization of oxidizable substances as oxidation-protective coatings for bodies facing high convective heat transfer in the atmosphere is presented.

Determining mechanical behavior of solid materials using miniature specimens

DOEpatents

Manahan, Michael P.; Argon, Ali S.; Harling, Otto K.

1986-01-01

A Miniaturized Bend Test (MBT) capable of extracting and determining mechanical behavior information from specimens only so large as to have at least a volume or smallest dimension sufficient to satisfy continuum behavior in all directions. The mechanical behavior of the material is determined from the measurements taken during the bending of the specimen and is processed according to the principles of linear or nonlinear material mechanics or both. In a preferred embodiment the determination is carried out by a code which is constructed according to the finite element method, and the specimen used for the determinations is a miniature disk simply supported for central loading at the axis on the center of the disk.

Corrosion and Fatigue Behavior of High-Strength Steel Treated with a Zn-Alloy Thermo-diffusion Coating

NASA Astrophysics Data System (ADS)

Mulligan, C. P.; Vigilante, G. N.; Cannon, J. J.

2017-11-01

High and low cycle fatigue tests were conducted on high-strength steel using four-point bending. The materials tested were ASTM A723 steel in the as-machined condition, grit-blasted condition, MIL-DTL-16232 heavy manganese phosphate-coated condition, and ASTM A1059 Zn-alloy thermo-diffusion coated (Zn-TDC). The ASTM A723 steel base material exhibits a yield strength of 1000 MPa. The effects of the surface treatments versus uncoated steel were examined. The fatigue life of the Zn-TDC specimens was generally reduced on as-coated specimens versus uncoated or phosphate-coated specimens. Several mechanisms are examined including the role of compressive residual stress relief with the Zn-TDC process as well as fatigue crack initiation from the hardened Zn-Fe alloy surface layer produced in the gas-metal reaction. Additionally, the effects of corrosion pitting on the fatigue life of coated specimens are explored as the Zn-TDC specimens exhibit significantly improved corrosion resistance over phosphate-coated and oiled specimens.

Influences of the manufacturing process chain design on the near surface condition and the resulting fatigue behaviour of quenched and tempered SAE 4140

NASA Astrophysics Data System (ADS)

Klein, M.; Eifler, D.

2010-07-01

To analyse interactions between single steps of process chains, variations in material properties, especially the microstructure and the resulting mechanical properties, specimens with tension screw geometry were manufactured with five process chains. The different process chains as well as their parameters influence the near surface condition and consequently the fatigue behaviour in a characteristic manner. The cyclic deformation behaviour of these specimens can be benchmarked equivalently with conventional strain measurements as well as with high-precision temperature and electrical resistance measurements. The development of temperature-values provides substantial information on cyclic load dependent changes in the microstructure.

Effect of Thermomechanical Processing and Crystallographic Orientation on the Corrosion Behavior of API 5L X70 Pipeline Steel

NASA Astrophysics Data System (ADS)

Ohaeri, Enyinnaya; Omale, Joseph; Eduok, Ubong; Szpunar, Jerzy

2018-04-01

This work presents the electrochemical response of X70 pipeline steel substrates thermomechanically processed at different conditions. The WE sample was hot rolled at a temperature range of 850 °C to 805 °C and cooled at a rate of 42.75 °C/s. Another sample WD was hot rolled from 880 °C to 815 °C and cooled at a faster rate of 51.5 °C/s. Corrosion tests were conducted electrochemically by potentiodynamic polarization in hydrogen-charged and non-hydrogen-charged environments. A lower corrosion rate was measured with hydrogen charging due to the rapid formation of corrosion product film on pipeline substrate, but WE specimen emerged as the most susceptible to corrosion with and without hydrogen charging. Variations in thermomechanical rolling conditions influenced grain orientation, protective film properties, corrosion, and cracking behavior on both specimens. Cracks were seen in both specimens after hydrogen charging, but specimen WE experienced a more intense deterioration of protective corrosion product film and subsequent cracking. A large part of specimen WD retained its protective corrosion product film after the polarization test, and sites where spalling occurred resulted in pitting with less cracking. Despite weak crystallographic texture noticed in both specimens, WD showed a higher intensity of corrosion-resistant 111||ND-oriented grains, while WE showed a more random distribution of 111||ND-, 011||ND-, and 001||ND-oriented grains with a lower intensity.

Effect of Thermomechanical Processing and Crystallographic Orientation on the Corrosion Behavior of API 5L X70 Pipeline Steel

NASA Astrophysics Data System (ADS)

Ohaeri, Enyinnaya; Omale, Joseph; Eduok, Ubong; Szpunar, Jerzy

2018-06-01

This work presents the electrochemical response of X70 pipeline steel substrates thermomechanically processed at different conditions. The WE sample was hot rolled at a temperature range of 850 °C to 805 °C and cooled at a rate of 42.75 °C/s. Another sample WD was hot rolled from 880 °C to 815 °C and cooled at a faster rate of 51.5 °C/s. Corrosion tests were conducted electrochemically by potentiodynamic polarization in hydrogen-charged and non-hydrogen-charged environments. A lower corrosion rate was measured with hydrogen charging due to the rapid formation of corrosion product film on pipeline substrate, but WE specimen emerged as the most susceptible to corrosion with and without hydrogen charging. Variations in thermomechanical rolling conditions influenced grain orientation, protective film properties, corrosion, and cracking behavior on both specimens. Cracks were seen in both specimens after hydrogen charging, but specimen WE experienced a more intense deterioration of protective corrosion product film and subsequent cracking. A large part of specimen WD retained its protective corrosion product film after the polarization test, and sites where spalling occurred resulted in pitting with less cracking. Despite weak crystallographic texture noticed in both specimens, WD showed a higher intensity of corrosion-resistant 111|| ND-oriented grains, while WE showed a more random distribution of 111|| ND-, 011|| ND-, and 001|| ND-oriented grains with a lower intensity.

[Quality Management and Quality Specifications of Laboratory Tests in Clinical Studies--Challenges in Pre-Analytical Processes in Clinical Laboratories].

PubMed

Ishibashi, Midori

2015-01-01

The cost, speed, and quality are the three important factors recently indicated by the Ministry of Health, Labour and Welfare (MHLW) for the purpose of accelerating clinical studies. Based on this background, the importance of laboratory tests is increasing, especially in the evaluation of clinical study participants' entry and safety, and drug efficacy. To assure the quality of laboratory tests, providing high-quality laboratory tests is mandatory. For providing adequate quality assurance in laboratory tests, quality control in the three fields of pre-analytical, analytical, and post-analytical processes is extremely important. There are, however, no detailed written requirements concerning specimen collection, handling, preparation, storage, and shipping. Most laboratory tests for clinical studies are performed onsite in a local laboratory; however, a part of laboratory tests is done in offsite central laboratories after specimen shipping. As factors affecting laboratory tests, individual and inter-individual variations are well-known. Besides these factors, standardizing the factors of specimen collection, handling, preparation, storage, and shipping, may improve and maintain the high quality of clinical studies in general. Furthermore, the analytical method, units, and reference interval are also important factors. It is concluded that, to overcome the problems derived from pre-analytical processes, it is necessary to standardize specimen handling in a broad sense.

Developing integrated workflows for the digitisation of herbarium specimens using a modular and scalable approach.

PubMed

Haston, Elspeth; Cubey, Robert; Pullan, Martin; Atkins, Hannah; Harris, David J

2012-01-01

Digitisation programmes in many institutes frequently involve disparate and irregular funding, diverse selection criteria and scope, with different members of staff managing and operating the processes. These factors have influenced the decision at the Royal Botanic Garden Edinburgh to develop an integrated workflow for the digitisation of herbarium specimens which is modular and scalable to enable a single overall workflow to be used for all digitisation projects. This integrated workflow is comprised of three principal elements: a specimen workflow, a data workflow and an image workflow.The specimen workflow is strongly linked to curatorial processes which will impact on the prioritisation, selection and preparation of the specimens. The importance of including a conservation element within the digitisation workflow is highlighted. The data workflow includes the concept of three main categories of collection data: label data, curatorial data and supplementary data. It is shown that each category of data has its own properties which influence the timing of data capture within the workflow. Development of software has been carried out for the rapid capture of curatorial data, and optical character recognition (OCR) software is being used to increase the efficiency of capturing label data and supplementary data. The large number and size of the images has necessitated the inclusion of automated systems within the image workflow.

A Proposed Set of Metrics to Reduce Patient Safety Risk From Within the Anatomic Pathology Laboratory

PubMed Central

Banks, Peter; Brown, Richard; Laslowski, Alex; Daniels, Yvonne; Branton, Phil; Carpenter, John; Zarbo, Richard; Forsyth, Ramses; Liu, Yan-hui; Kohl, Shane; Diebold, Joachim; Masuda, Shinobu; Plummer, Tim

2017-01-01

Background: Anatomic pathology laboratory workflow consists of 3 major specimen handling processes. Among the workflow are preanalytic, analytic, and postanalytic phases that contain multistep subprocesses with great impact on patient care. A worldwide representation of experts came together to create a system of metrics, as a basis for laboratories worldwide, to help them evaluate and improve specimen handling to reduce patient safety risk. Method: Members of the Initiative for Anatomic Pathology Laboratory Patient Safety (IAPLPS) pooled their extensive expertise to generate a list of metrics highlighting processes with high and low risk for adverse patient outcomes. Results: Our group developed a universal, comprehensive list of 47 metrics for patient specimen handling in the anatomic pathology laboratory. Steps within the specimen workflow sequence are categorized as high or low risk. In general, steps associated with the potential for specimen misidentification correspond to the high-risk grouping and merit greater focus within quality management systems. Primarily workflow measures related to operational efficiency can be considered low risk. Conclusion: Our group intends to advance the widespread use of these metrics in anatomic pathology laboratories to reduce patient safety risk and improve patient care with development of best practices and interlaboratory error reporting programs. PMID:28340232

A Proposed Set of Metrics to Reduce Patient Safety Risk From Within the Anatomic Pathology Laboratory.

PubMed

Banks, Peter; Brown, Richard; Laslowski, Alex; Daniels, Yvonne; Branton, Phil; Carpenter, John; Zarbo, Richard; Forsyth, Ramses; Liu, Yan-Hui; Kohl, Shane; Diebold, Joachim; Masuda, Shinobu; Plummer, Tim; Dennis, Eslie

2017-05-01

Anatomic pathology laboratory workflow consists of 3 major specimen handling processes. Among the workflow are preanalytic, analytic, and postanalytic phases that contain multistep subprocesses with great impact on patient care. A worldwide representation of experts came together to create a system of metrics, as a basis for laboratories worldwide, to help them evaluate and improve specimen handling to reduce patient safety risk. Members of the Initiative for Anatomic Pathology Laboratory Patient Safety (IAPLPS) pooled their extensive expertise to generate a list of metrics highlighting processes with high and low risk for adverse patient outcomes. : Our group developed a universal, comprehensive list of 47 metrics for patient specimen handling in the anatomic pathology laboratory. Steps within the specimen workflow sequence are categorized as high or low risk. In general, steps associated with the potential for specimen misidentification correspond to the high-risk grouping and merit greater focus within quality management systems. Primarily workflow measures related to operational efficiency can be considered low risk. Our group intends to advance the widespread use of these metrics in anatomic pathology laboratories to reduce patient safety risk and improve patient care with development of best practices and interlaboratory error reporting programs. © American Society for Clinical Pathology 2017.

Microstructure and fatigue resistance of high strength dual phase steel welded with gas metal arc welding and plasma arc welding processes

NASA Astrophysics Data System (ADS)

Ahiale, Godwin Kwame; Oh, Yong-Jun; Choi, Won-Doo; Lee, Kwang-Bok; Jung, Jae-Gyu; Nam, Soo Woo

2013-09-01

This study presents the microstructure and high cycle fatigue performance of lap shear joints of dual phase steel (DP590) welded using gas metal arc welding (GMAW) and plasma arc welding (PAW) processes. High cycle fatigue tests were conducted on single and double lap joints under a load ratio of 0.1 and a frequency of 20 Hz. In order to establish a basis for comparison, both weldments were fabricated to have the same weld depth in the plate thickness. The PAW specimens exhibited a higher fatigue life, a gentle S-N slope, and a higher fatigue limit than the GMAW specimens. The improvement in the fatigue life of the PAW specimens was primarily attributed to the geometry effect that exhibited lower and wider beads resulting in a lower stress concentration at the weld toe where cracks initiate and propagate. Furthermore, the microstructural constituents in the heat-affected zone (HAZ) of the PAW specimens contributed to the improvement. The higher volume fraction of acicular ferrite in the HAZ beneath the weld toe enhanced the PAW specimen's resistance to fatigue crack growth. The double lap joints displayed a higher fatigue life than the single lap joints without changing the S-N slope.

Hydrogen Cracking in Gas Tungsten Arc Welding of an AISI Type 321 Stainless Steel

NASA Astrophysics Data System (ADS)

Rozenak, P.; Unigovski, Ya.; Shneck, R.

The effects of in situ cathodic charging on the tensile properties and susceptibility to cracking of an AISI type 321 stainless steel, welded by the gas tungsten arc welding (GTAW) process, was studied by various treatments. Appearance of delta-ferrite phase in the as-welded steels in our tested conditions was observed with discontinuous grain boundaries (M23C6) and a dense distribution of metal carbides MC ((Ti, Nb)C), which precipitated in the matrix. Shielding gas rates changes the mechanical properties of the welds. Ultimate tensile strength and ductility are increases with the resistance to the environments related the increase of the supplied shielding inert gas rates. Charged specimens, caused mainly in decreases in the ductility of welded specimens. However, more severe decrease in ductility was obtained after post weld heat treatment (PWHT). The fracture of sensitized specimens was predominantly intergranular, whereas the as-welded specimens exhibited massive transgranular regions. Both types of specimen demonstrated narrow brittle zones at the sides of the fracture surface and ductile micro-void coalescences in the middle. Ferrite δ was form after welding with high density of dislocation structures and stacking faults formation and the thin stacking fault plates with e-martensite phase were typically found in the austenitic matrix after the cathodical charging process.

Scatter of fatigue data owing to material microscopic effects

NASA Astrophysics Data System (ADS)

Tang, XueSong

2014-01-01

A common phenomenon of fatigue test data reported in the open literature such as S-N curves exhibits the scatter of points for a group of same specimens under the same loading condition. The reason is well known that the microstructure is different from specimen to specimen even in the same group. Specifically, a fatigue failure process is a multi-scale problem so that a fatigue failure model should have the ability to take the microscopic effect into account. A physically-based trans-scale crack model is established and the analytical solution is obtained by coupling the micro- and macro-scale. Obtained is the trans-scale stress intensity factor as well as the trans-scale strain energy density (SED) factor. By taking this trans-scale SEDF as a key controlling parameter for the fatigue crack propagation from micro- to macro-scale, a trans-scale fatigue crack growth model is proposed in this work which can reflect the microscopic effect and scale transition in a fatigue process. The fatigue test data of aluminum alloy LY12 plate specimens is chosen to check the model. Two S-N experimental curves for cyclic stress ratio R=0.02 and R=0.6 are selected. The scattering test data points and two S-N curves for both R=0.02 and R=0.6 are exactly re-produced by application of the proposed model. It is demonstrated that the proposed model is able to reflect the multiscaling effect in a fatigue process. The result also shows that the microscopic effect has a pronounced influence on the fatigue life of specimens.

Creating & using specimen images for collection documentation, research, teaching and outreach

NASA Astrophysics Data System (ADS)

Demouthe, J. F.

2012-12-01

In this age of digital media, there are many opportunities for use of good images of specimens. On-line resources such as institutional web sites and global sites such as PaleoNet and the Paleobiology Database provide venues for collection information and images. Pictures can also be made available to the general public through popular media sites such as Flickr and Facebook, where they can be retrieved and used by teachers, students, and the general public. The number of requests for specimen loans can be drastically reduced by offering the scientific community access to data and specimen images using the internet. This is an important consideration in these days of limited support budgets, since it reduces the amount of staff time necessary for giving researchers and educators access to collections. It also saves wear and tear on the specimens themselves. Many institutions now limit or refuse to send specimens out of their own countries because of the risks involved in going through security and customs. The internet can bridge political boundaries, allowing everyone equal access to collections. In order to develop photographic documentation of a collection, thoughtful preparation will make the process easier and more efficient. Acquire the necessary equipment, establish standards for images, and develop a simple workflow design. Manage images in the camera, and produce the best possible results, rather than relying on time-consuming editing after the fact. It is extremely important that the images of each specimen be of the highest quality and resolution. Poor quality, low resolution photos are not good for anything, and will often have to be retaken when another need arises. Repeating the photography process involves more handling of specimens and more staff time. Once good photos exist, smaller versions can be created for use on the web. The originals can be archived and used for publication and other purposes.

Quality Measures in Pre-Analytical Phase of Tissue Processing: Understanding Its Value in Histopathology.

PubMed

Rao, Shalinee; Masilamani, Suresh; Sundaram, Sandhya; Duvuru, Prathiba; Swaminathan, Rajendiran

2016-01-01

Quality monitoring in histopathology unit is categorized into three phases, pre-analytical, analytical and post-analytical, to cover various steps in the entire test cycle. Review of literature on quality evaluation studies pertaining to histopathology revealed that earlier reports were mainly focused on analytical aspects with limited studies on assessment of pre-analytical phase. Pre-analytical phase encompasses several processing steps and handling of specimen/sample by multiple individuals, thus allowing enough scope for errors. Due to its critical nature and limited studies in the past to assess quality in pre-analytical phase, it deserves more attention. This study was undertaken to analyse and assess the quality parameters in pre-analytical phase in a histopathology laboratory. This was a retrospective study done on pre-analytical parameters in histopathology laboratory of a tertiary care centre on 18,626 tissue specimens received in 34 months. Registers and records were checked for efficiency and errors for pre-analytical quality variables: specimen identification, specimen in appropriate fixatives, lost specimens, daily internal quality control performance on staining, performance in inter-laboratory quality assessment program {External quality assurance program (EQAS)} and evaluation of internal non-conformities (NC) for other errors. The study revealed incorrect specimen labelling in 0.04%, 0.01% and 0.01% in 2007, 2008 and 2009 respectively. About 0.04%, 0.07% and 0.18% specimens were not sent in fixatives in 2007, 2008 and 2009 respectively. There was no incidence of specimen lost. A total of 113 non-conformities were identified out of which 92.9% belonged to the pre-analytical phase. The predominant NC (any deviation from normal standard which may generate an error and result in compromising with quality standards) identified was wrong labelling of slides. Performance in EQAS for pre-analytical phase was satisfactory in 6 of 9 cycles. A low incidence of errors in pre-analytical phase implies that a satisfactory level of quality standards was being practiced with still scope for improvement.

Transverse Isotropy of Phyllite Under Brazilian Tests: Laboratory Testing and Numerical Simulations

NASA Astrophysics Data System (ADS)

Xu, Guowen; He, Chuan; Chen, Ziquan; Su, Ang

2018-04-01

Phyllite is a low-grade, metamorphic rock with well-developed foliation. We characterized the fracture pattern and failure strength of phyllite specimens under Brazilian tests. The specimens were obtained from the Zhegu mountain tunnel in China and had different foliation-loading angles, namely 0°, 15°, 30°, 45°, 60°, 75° and 90°. The processes for the initiation and propagation of macro-cracks were recorded using high-speed photography. The evolution of micro-cracks was analyzed based on the results of acoustic emission (AE) tests. The failure process of the specimens during the Brazilian tests was simulated with a new numerical approach based on the particle discrete element method. The influence of foliation strength and the microstructure of the rock matrix were also studied numerically. The experimental results showed that the failure strength of the specimens was related to their fracture patterns and the areas of their fracture surfaces. The initial cracking point of the specimens appeared at the upper or lower loading position, and the cracks propagated to the boundaries of the specimens along or across foliation. The temporal distributions of the AE counts and AE energy of the specimens were affected predominantly by the fracture pattern, and we divided these distributions into two modes: the peak mode and the uniformly distributed mode. The numerical results indicated that the fracture surface was roughly parallel to the loading direction and that the surface was located in the central part of the disk specimens for rocks with loose structure (low coordination number or large crack density) or with strong foliation, i.e., foliation with high shear strength. The failure pattern and trends of variation in failure strength as a function of foliation-loading angles varied with the ratio of cohesion to the tensile strength of foliation, the crack density, and the coordination number.

Regulatory T-cell cytokines in patients with nonsegmental vitiligo.

PubMed

Kidir, Mehtap; Karabulut, Ayse A; Ercin, Mustafa E; Atasoy, Pınar

2017-05-01

In the etiopathogenesis of vitiligo, the role of suppressor cytokines, such as transforming growth factor-β (TGF-β) and interleukin-10 (IL-10), associated with regulatory T-cells (Treg) is not completely known. In this study, the role of Treg-cell functions in the skin of patients with nonsegmental vitiligo was investigated. Lesional and nonlesional skin samples from 30 adult volunteers ranging in age from 18 to 36 years with nonsegmental vitiligo were compared with normal skin area excision specimens of 30 benign melanocytic nevus cases as controls. All samples were evaluated staining for forkhead box P3 (Foxp3), TGF-β, and IL-10 using the standardized streptavidin-biotin immunoperoxidase immunohistochemistry method. Foxp3 expression was lower in lesional vitiligo skin specimens compared to controls; it was also lower in lesional vitiligo specimens than nonlesional vitiligo specimens. IL-10 levels were lower in lesional vitiligo specimens compared to the controls, whereas IL-10 expression was significantly lower in lesional specimens compared with nonlesional specimens. TGF-β expression was higher in both lesional and nonlesional skin specimens of patients with vitiligo compared to controls. TGF-β expression was lower in lesional skin specimens than nonlesional skin specimens. In addition, there was no significant correlation between Foxp3 expression with TGF-β and IL-10 expressions in lesional skin specimens in the vitiligo group. In this study, results supporting the contribution of Treg cells and IL-10 deficiency to the autoimmune process were obtained. Therefore, future studies are necessary to demonstrate the definitive role of Treg-cell functions in the etiopathogenesis of vitiligo. © 2017 The International Society of Dermatology.

Rapid embedding methods into epoxy and LR White resins for morphological and immunological analysis of cryofixed biological specimens.

PubMed

McDonald, Kent L

2014-02-01

A variety of specimens including bacteria, ciliates, choanoflagellates (Salpingoeca rosetta), zebrafish (Danio rerio) embryos, nematode worms (Caenorhabditis elegans), and leaves of white clover (Trifolium repens) plants were high pressure frozen, freeze-substituted, infiltrated with either Epon, Epon-Araldite, or LR White resins, and polymerized. Total processing time from freezing to blocks ready to section was about 6 h. For epoxy embedding the specimens were freeze-substituted in 1% osmium tetroxide plus 0.1% uranyl acetate in acetone. For embedding in LR White the freeze-substitution medium was 0.2% uranyl acetate in acetone. Rapid infiltration was achieved by centrifugation through increasing concentrations of resin followed by polymerization at 100°C for 1.5-2 h. The preservation of ultrastructure was comparable to standard freeze substitution and resin embedding methods that take days to complete. On-section immunolabeling results for actin and tubulin molecules were positive with very low background labeling. The LR White methods offer a safer, quicker, and less-expensive alternative to Lowicryl embedding of specimens processed for on-section immunolabeling without traditional aldehyde fixatives.

Measurement of material mechanical properties in microforming

NASA Astrophysics Data System (ADS)

Yun, Wang; Xu, Zhenying; Hui, Huang; Zhou, Jianzhong

2006-02-01

As the rapid market need of micro-electro-mechanical systems engineering gives it the wide development and application ranging from mobile phones to medical apparatus, the need of metal micro-parts is increasing gradually. Microforming technology challenges the plastic processing technology. The findings have shown that if the grain size of the specimen remains constant, the flow stress changes with the increasing miniaturization, and also the necking elongation and the uniform elongation etc. It is impossible to get the specimen material properties in conventional tensile test machine, especially in the high precision demand. Therefore, one new measurement method for getting the specimen material-mechanical property with high precision is initiated. With this method, coupled with the high speed of Charge Coupled Device (CCD) camera and high precision of Coordinate Measuring Machine (CMM), the elongation and tensile strain in the gauge length are obtained. The elongation, yield stress and other mechanical properties can be calculated from the relationship between the images and CCD camera movement. This measuring method can be extended into other experiments, such as the alignment of the tool and specimen, micro-drawing process.

The effect of an overload on the rate of fatigue crack propagation under plane stress conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bao, H.; McEvily, A.J.

1995-07-01

It has been shown that the retardation in the rate of fatigue crack growth following an overload is largely the result of surface-related, plane-stress deformation. In the present article, in order to isolate the plane-stress behavior, the effect of an overload on the subsequent rate of fatigue crack growth of 0.3-mm-thick specimens of 9Cr-1Mo steel has been investigated and compared to results obtained using 6.35-mm-thick specimens. It was found that for the 0.3-mm thickness, as with thicker specimens, two opening load levels were associated with the overload process. The upper opening load is associated with plane-stress deformation in the overloadmore » plastic zone, and this opening process is more clearly observed with thin as compared to thicker specimens. Based upon the determined level of the upper opening load, a semiempirical analysis is developed for calculating the number of delay cycles due to an overload as a function of thickness.« less

[Evaluation of Xpert® MTB/RIF technique for Mycobacterium tuberculosis complex detection in extra-respiratory specimens].

PubMed

García, Patricia; Balcells, M Elvira; Castillo, Claudia; Miranda, Carolina; Geoffroy, Enrique; Román, Juan C; Wozniak, Aniela

2017-08-01

Extra-pulmonary tuberculosis (TB) represents the 26.2% of total TB cases in Chile. Culture is the gold standard method, but the process is extremely slow. Xpert®MTB/RIF technique detects Mycobacterium tuberculosis complex (MTBc) through real time PCR in less than 3 h. However, it has been validated only for respiratory specimens. We aimed to determine the performance of Xpert®MTB/RIF test in detecting MTBc in extra-respiratory specimens compared with a combined gold standard consisting in a positive (liquid and solid) mycobacterial culture and/or a positive validated molecular method (q-RPC, Cobas®TaqMan®-MTB). Fifty extra-respiratory specimens were analyzed, from which 25 were positive and 25 negative for MTBc based on the combined gold standard. The 25 positive specimens had a positive result by Xpert®MTB/RIF; from the 25 negative specimens, 24 had a negative result and one had a positive result. We obtained an overall concordance of 98% between Xpert®MTB/RIF and the combined gold standard. Xpert®MTB/RIF test was able to detect 12 smear-negative specimens and 3 culture-negative specimens, all of them corresponding to extra-pulmonary TB cases. Xpert®MTB/RIF showed similar sensitivity to q-RPC in detecting MTBc in extra-respiratory specimens. This procedure allowed a substantial reduction in the time of diagnosis.

System and method for monitoring cellular activity

NASA Technical Reports Server (NTRS)

Bearman, Gregory H. (Inventor); Fraser, Scott E. (Inventor); Lansford, Russell D. (Inventor)

2002-01-01

A system and method for monitoring cellular activity in a cellular specimen. According to one embodiment, a plurality of excitable markers are applied to the specimen. A multi-photon laser microscope is provided to excite a region of the specimen and cause fluorescence to be radiated from the region. The radiating fluorescence is processed by a spectral analyzer to separate the fluorescence into respective wavelength bands. The respective bands of fluorescence are then collected by an array of detectors, with each detector receiving a corresponding one of the wavelength bands.

System and method for monitoring cellular activity

NASA Technical Reports Server (NTRS)

Bearman, Gregory H. (Inventor); Fraser, Scott E. (Inventor); Lansford, Russell D. (Inventor)

2004-01-01

A system and method for monitoring cellular activity in a cellular specimen. According to one embodiment, a plurality of excitable markers are applied to the specimen. A multi-photon laser microscope is provided to excite a region of the specimen and cause fluorescence to be radiated from the region. The radiating fluorescence is processed by a spectral analyzer to separate the fluorescence into respective wavelength bands. The respective bands of fluorescence are then collected by an array of detectors, with each detector receiving a corresponding one of the wavelength bands.

Basic failure mechanisms in advanced composites

NASA Technical Reports Server (NTRS)

Mullin, J. V.; Mazzio, V. F.; Mehan, R. L.

1972-01-01

Failure mechanisms in carbon-epoxy composites are identified as a basis for more reliable prediction of the performance of these materials. The approach involves both the study of local fracture events in model specimens containing small groups of filaments and fractographic examination of high fiber content engineering composites. Emphasis is placed on the correlation of model specimen observations with gross fracture modes. The effects of fiber surface treatment, resin modification and fiber content are studied and acoustic emission methods are applied. Some effort is devoted to analysis of the failure process in composite/metal specimens.

End Restraints for Impact-Energy-Absorbing Tube Specimens

NASA Technical Reports Server (NTRS)

Farley, G. L.; Modlin, J. T.

1985-01-01

Inexpensive device developed that eliminates tipping problem without affecting crushing process. Device consists of soft sponge-rubber insert approximately 0.5 inches (1.3 centimeters) thick, cut to same diameter as internal diameter of tube specimen. Metal washer, slightly smaller than internal diameter of tube, placed on top of rubber insert. Screw passed through washer and rubber insert and threaded into base of test machine. As screw tightened against washer, rubber insert compressed and expands radially. Radial expansion applies pressure against internal wall of tube specimen, which provides sufficient support to tube to prevent tipping.

Gas levitator having fixed levitation node for containerless processing

NASA Technical Reports Server (NTRS)

Berge, L. H.; Oran, W. A.; Theiss, M. (Inventor)

1981-01-01

A method and apparatus is disclosed for levitating a specimen of material in a containerless environment at a stable nodal position independent of gravity. An elongated levitation tube has a contoured interior in the form of convergent section, constriction, and a divergent section in which the levitation node is created. A gas flow control means prevents separation of flow from the interior walls in the region of a specimen. The apparatus provides for levitating and heating the specimen simultaneously by combustion of a suitable gas mixture combined with an inert gas.

Toward the Atomic-Level Mass Analysis of Biomolecules by the Scanning Atom Probe.

PubMed

Nishikawa, Osamu; Taniguchi, Masahiro

2017-04-01

In 1994, a new type of atom probe instrument, named the scanning atom probe (SAP), was proposed. The unique feature of the SAP is the introduction of a small extraction electrode, which scans over a specimen surface and confines the high field, required for field evaporation of surface atoms in a small space, between the specimen and the electrode. Thus, the SAP does not require a sharp specimen tip. This indicates that the SAP can mass analyze the specimens which are difficult to form in a sharp tip, such as organic materials and biomolecules. Clean single wall carbon nanotubes (CNT), made by high-pressure carbon monoxide process are found to be the best substrates for biomolecules. Various amino acids and dipeptide biomolecules were successfully mass analyzed, revealing characteristic clusters formed by strongly bound atoms in the specimens. The mass analysis indicates that SAP analysis of biomolecules is not only qualitative, but also quantitative.

Flaw growth of 7075, 7475, 7050 and 7049 aluminum alloy plate in stress corrosion environments: 4-year marine atmosphere results

NASA Technical Reports Server (NTRS)

Hasse, K. R.; Dorward, R. C.

1981-01-01

After nearly 53 months of exposure to marine atmosphere, crack growth in SL DCB specimens from 7075, 7475, 7050, and 7049-T7X plate has slowed to the arbitrary 10 to the -10 power m/sec used to define threshold stress intensity. Because some specimens appear to be approaching crack arrest, the importance of self-loading from corrosion product wedging as a significant driving force for crack propagation in overaged materials is questioned. Crack length-time data were analyzed using a computer curve fitting program which minimized the effects of normal data scatter, and provided a clearer picture of material performance. Precracked specimen data are supported by the results of smooth specimen tests. Transgranular stress corrosion cracking was observed in TL DCB specimens from all four alloys. This process is extremely slow and is characterized by a striated surface morphology.

Molecular detection of candida species from hospitalized patient’s specimens.

PubMed

Camacho-Cardoso, José Luis; Martínez-Rivera, María Ángeles; Manzano-Gayosso, Patricia; Méndez-Tovar, Luis Javier; López-Martínez, Rubén; Hernández-Hernández, Francisca

To identify the most frequent Candida species in specimens from patients hospitalized in different medical centers of Mexico City, with suspected fungal infection. Specimens were grown on Sabouraud dextrose agar at 28°C for 72 h. In addition, DNA was extracted. Isolates were grown on CHROMagar Candida™, at 37°C for 48 h. The molecular identification was performed by polymerase chain reaction (PCR) using primers specific for four species. Eighty one specimens were processed and included: bronchial lavage, pleural, cerebrospinal, peritoneal, ascites and bile fluids; blood, sputum, bone marrow, oro-tracheal cannula and ganglion. By culture, 30 samples (37%) were positive, and by PCR, 41 (50.6%). By PCR, the frequency of species was: Candida albicans 82.9%, Candida tropicalis 31.7%, Candida glabrata 24.4%, and Candida parapsilosis 4.9%. In 34.1% of specimens a species mixture was detected suggesting a co-infection: Two species in five specimens (C. albicans-C tropicalis and C. albicans-C glabrata), and three species in three specimens (C. albicans-C. glabrata-C. tropicalis). The PCR is an useful tool for detection the most common Candida species causing infection in hospitalized patients, it avoids the requirement of culture weather we start from clinical specimen and it favors the early diagnosis of invasive candidiasis. Copyright: © 2017 SecretarÍa de Salud

Metal shadowing for electron microscopy.

PubMed

Hendricks, Gregory M

2014-01-01

Metal shadowing of bacteria, viruses, isolated molecules, and macromolecular assemblies is another high-resolution method for observing the ultrastructure of biological specimens. The actual procedure for producing a metal shadow is relatively simple; a heavy metal is evaporated from a source at an oblique angle to the specimen. The metal atoms pile up on the surfaces that face the source, but the surfaces away from the source are shielded and receive little metal deposit, creating a "shadow." However, the process of producing biological specimens that are suitable for metal shadowing can be very complex. There are a whole host of specimen preparation techniques that can precede metal shadowing, and all provide superior preservation in comparison to air drying, a required step in negative staining procedures. The physical forces present during air drying (i.e., surface tension of the water-air interface) will literally crush most biological specimens as they dry. In this chapter I explain the development of and procedures for the production of biological specimens from macromolecular assemblies (e.g., DNA and RNA), purified isolated molecules (e.g., proteins), and isolated viruses and bacteria preparations suitable for metal shadowing. A variation on this basic technique is to rotate the specimen during the metal deposition to produce a high-resolution three-dimensional rendering of the specimen.

Detection, Mapping, and Quantification of Single Walled Carbon Nanotubes in Histological Specimens with Photoacoustic Microscopy

PubMed Central

Mikos, Antonios G.; Jansen, John A.; Shroyer, Kenneth R.; Wang, Lihong V.; Sitharaman, Balaji

2012-01-01

Aims In the present study, the efficacy of multi-scale photoacoustic microscopy (PAM) was investigated to detect, map, and quantify trace amounts [nanograms (ng) to micrograms (µg)] of SWCNTs in a variety of histological tissue specimens consisting of cancer and benign tissue biopsies (histological specimens from implanted tissue engineering scaffolds). Materials and Methods Optical-resolution (OR) and acoustic-resolution (AR) - Photoacoustic microscopy (PAM) was employed to detect, map and quantify the SWCNTs in a variety of tissue histological specimens and compared with other optical techniques (bright-field optical microscopy, Raman microscopy, near infrared (NIR) fluorescence microscopy). Results Both optical-resolution and acoustic-resolution PAM, allow the detection and quantification of SWCNTs in histological specimens with scalable spatial resolution and depth penetration. The noise-equivalent detection sensitivity to SWCNTs in the specimens was calculated to be as low as ∼7 pg. Image processing analysis further allowed the mapping, distribution, and quantification of the SWCNTs in the histological sections. Conclusions The results demonstrate the potential of PAM as a promising imaging technique to detect, map, and quantify SWCNTs in histological specimens, and could complement the capabilities of current optical and electron microscopy techniques in the analysis of histological specimens containing SWCNTs. PMID:22496892

In Situ Thermal Imagery of Antarctic Meteorites and Their Stability on the Ice Surface

NASA Technical Reports Server (NTRS)

Harvey, R. P.; Righter, M.; Karner, J. M.; Hyneck, B.; Keller, L.; Meshik, A.; Mittlefehldt, D.; Radebaugh, J.; Rougeux, B.; Schutt, J.

2017-01-01

The mechanisms behind Antarctic meteorite concentrations remain enigmatic nearly 5 decades after the first recoveries, and much of the research in this direction has been based on anedcotal evidence. While these observations suggest many plausible processes that help explain Antarctic meteorite concentrations, the relative importance of these various processes (which can result in either an increase or decrease of specimens) is a critical component of any more robust model of how these concentrations form. During the 2016-2017 field season of the US Antarctic Search for Meteorites program we aquired in situ thermal imagery of meteorites specimens that provide semi-quantitative assesment of the relative temperature of these specimens and the ice. These provide insight into one hypothesized loss mechanism, the downward thermal tunnelling of meteorites warmed in the sun.

Patient identification error among prostate needle core biopsy specimens--are we ready for a DNA time-out?

PubMed

Suba, Eric J; Pfeifer, John D; Raab, Stephen S

2007-10-01

Patient identification errors in surgical pathology often involve switches of prostate or breast needle core biopsy specimens among patients. We assessed strategies for decreasing the occurrence of these uncommon and yet potentially catastrophic events. Root cause analyses were performed following 3 cases of patient identification error involving prostate needle core biopsy specimens. Patient identification errors in surgical pathology result from slips and lapses of automatic human action that may occur at numerous steps during pre-laboratory, laboratory and post-laboratory work flow processes. Patient identification errors among prostate needle biopsies may be difficult to entirely prevent through the optimization of work flow processes. A DNA time-out, whereby DNA polymorphic microsatellite analysis is used to confirm patient identification before radiation therapy or radical surgery, may eliminate patient identification errors among needle biopsies.

Joining strength performances of metal skin and CFRP core laminate structures realized by compression-curing process, with supporting experiments

NASA Astrophysics Data System (ADS)

Quagliato, Luca; Jang, Changsoon; Kim, Naksoo

2018-05-01

In the recent years, the trend of lightening vehicles and structures of every kind has become an ever-growing issue, both for university and industrial researchers. As demonstrated in previous authors' works, laminate structures made of metal skin (MS) and carbon fiber reinforced polymer (CFRP) core show high specific bending strength properties while granting considerable weight reduction but, so far, no investigations have been carried out on the hole sensitivity and joinability of these hybrid structures. In the present research work, the hole size sensitivity of MS-CFRP structure has been studied by means of uniaxial tensile test on 160mm (length), 25mm (width), 2.0mm (average thickness) specimens bored with Ø06mm, Ø9mm, and Ø12mm holes. The specimen thickness is composed of two metal skins of 0.4mm thickness each, 8×0.2mm CFRP stacked layers and two thin epoxy-based adhesive layers. The specimens have been manufactured by means of a compression-curing process in which the different materials are stacked and, thanks to die pressure and temperature, the curing process is completed in a relatively short time (15˜20 minutes). The specimens have been tested by means of simple tension test showing that, for the MS-CFRP material, the smaller the hole the smaller the maximum bearable load. Moreover, specimens with the same hole sizes have been bolted together with class 12 resistance bolts and tested by means of tensile test, allowing to determine the maximum transferable load between the two MS-CFRP plates. Aiming to prove the improvement in the specific transferable load, experiments on only-steel specimens with the same weight of the MS-CFRP ones and joined with the same method and bolts have been carried out, allowing to conclude that, for the 9mm hole bolted plates, the proposed material has a specific maximum transferable 27% higher than that of the steel composing their skins.

Determining mechanical behavior of solid materials using miniature specimens

DOEpatents

Manahan, M.P.; Argon, A.S.; Harling, O.K.

1986-02-04

A Miniaturized Bend Test (MBT) capable of extracting and determining mechanical behavior information from specimens only so large as to have at least a volume or smallest dimension sufficient to satisfy continuum behavior in all directions is disclosed. The mechanical behavior of the material is determined from the measurements taken during the bending of the specimen and is processed according to the principles of linear or nonlinear material mechanics or both. In a preferred embodiment the determination is carried out by a code which is constructed according to the finite element method, and the specimen used for the determinations is a miniature disk simply supported for central loading at the axis on the center of the disk. 51 figs.

Modified low-temperture direct bonding method for vacuum microelectronics application

NASA Astrophysics Data System (ADS)

Ju, Byeong-Kwon; Lee, Duck-Jung; Choi, Woo-Beom; Lee, Yun-Hi; Jang, Jin; Lee, Kwang-Bae; Oh, Myung-Hwan

1997-06-01

This paper presents the process and experimental results for the improved silicon-to-glass bonding using silicon direct bonding (SDB) followed by anodic bonding. The initial bonding between glass and silicon was caused by the hydrophilic surfaces of silicon-glass ensemble using SDB method. Then the initially bonded specimen had to be strongly bonded by anodic bonding process. The effects of the bonding process parameters on the interface energy were investigated as functions of the bonding temperature and voltage. We found that the specimen which was bonded using SDB process followed by anodic bonding process had higher interface energy than one using anodic bonding process only. The main factor contributing to the higher interface energy in the glass-to-silicon assemble bonded by SDB followed by anodic bonding was investigated by secondary ion mass spectroscopy analysis.

Evaluation of the BD Vacutainer Plus Urine C&S Preservative Tubes compared with nonpreservative urine samples stored at 4°C and room temperature.

PubMed

Eisinger, Stephen W; Schwartz, Matthew; Dam, Lisa; Riedel, Stefan

2013-09-01

The stability of urine specimens submitted for culture remains a challenge for many laboratories because of delays in specimen transport. We evaluated the usefulness of BD Vacutainer Plus Urine C&S Preservative Tube in ensuring specimen stability. Clinical urine specimens collected in sterile collection cups (n = 110) were plated onto sheep blood and MacConkey agar following standard laboratory procedures guidelines. Thereafter, specimens were divided into 3 storage conditions: nonpreservative, refrigerated; nonpreservative, room temperature (RT); BD Vacutainer Plus Urine C&S Preservative Tube, RT. For each sample type, additional cultures were set up at 2, 4, 24, and 48 hours. Initially, 18 specimens had no growth, 32 showed mixed skin flora, and 60 yielded at least 1 uropathogen. Increased colony counts of uropathogens were observed for nonpreserved urine samples stored at RT; these changes were statistically significant. Minor differences between refrigerated urine samples and BD Vacutainer Plus Urine C&S Preservative Tube samples were seen but were not statistically significant. The use of preservative-containing collection tubes is desirable to ensure specimen stability when prompt processing or refrigeration is not feasible.

Dynamic Response and Failure Mechanism of Brittle Rocks Under Combined Compression-Shear Loading Experiments

NASA Astrophysics Data System (ADS)

Xu, Yuan; Dai, Feng

2018-03-01

A novel method is developed for characterizing the mechanical response and failure mechanism of brittle rocks under dynamic compression-shear loading: an inclined cylinder specimen using a modified split Hopkinson pressure bar (SHPB) system. With the specimen axis inclining to the loading direction of SHPB, a shear component can be introduced into the specimen. Both static and dynamic experiments are conducted on sandstone specimens. Given carefully pulse shaping, the dynamic equilibrium of the inclined specimens can be satisfied, and thus the quasi-static data reduction is employed. The normal and shear stress-strain relationships of specimens are subsequently established. The progressive failure process of the specimen illustrated via high-speed photographs manifests a mixed failure mode accommodating both the shear-dominated failure and the localized tensile damage. The elastic and shear moduli exhibit certain loading-path dependence under quasi-static loading but loading-path insensitivity under high loading rates. Loading rate dependence is evidently demonstrated through the failure characteristics involving fragmentation, compression and shear strength and failure surfaces based on Drucker-Prager criterion. Our proposed method is convenient and reliable to study the dynamic response and failure mechanism of rocks under combined compression-shear loading.

An Information Storage and Retrieval System for Biological and Geological Data. Interim Report.

ERIC Educational Resources Information Center

Squires, Donald F.

A project is being conducted to test the feasibility of an information storage and retrieval system for museum specimen data, particularly for natural history museums. A pilot data processing system has been developed, with the specimen records from the national collections of birds, marine crustaceans, and rocks used as sample data. The research…

Shear bond strength between resin cement and colored zirconia made with metal chlorides.

PubMed

Kim, Ga-Hyun; Park, Sang-Won; Lee, Kwangmin; Oh, Gye-Jeong; Lim, Hyun-Pil

2015-06-01

Although the application of zirconia in esthetic prostheses has increased, the shear bond strength (SBS) between colored zirconia and resin cement has not been investigated. The purpose of this study was to compare the SBS between resin cement and colored zirconia made with metal chlorides. Sixty-four zirconia specimens were divided into 2 groups: one in which the specimens were bonded with resin cement, including 4-META (4-methacryloxyethyl trimellitic anhydride), and one in which the specimens were bonded with resin cement (SEcure, Sun Medical) after being processed with zirconia primer (Zirconia Liner), including 4-META. Each group was then divided into 4 subgroups depending on the coloring liquid. The subgroups were noncolored (control), commercial coloring liquid VITA In-Ceram 2000 YZ LL1, aqueous chromium chloride solution 0.1 wt%, and aqueous molybdenum chloride solution 0.1 wt%. Composite resin cylinders (Filtek Z250, 3M ESPE) were fabricated and bonded to the surface of the zirconia specimen with resin cement (SEcure). All specimens were stored in 37°C distilled water for 24 hours, and the SBS was measured with a universal testing machine. All data were analyzed statistically with 2-way ANOVA and tested post hoc with the Tukey test (α=.05). Significant differences were observed among the SBS values of the colored zirconia depending on the coloring liquid (P<.001) and whether they were processed with zirconia primer (P<.001). The SBS between colored zirconia and resin cement was significantly higher than that of noncolored zirconia and resin cement in groups processed with zirconia primer (P<.05). Colored zirconia immersed in aqueous molybdenum chloride solution showed a significantly higher SBS. Coloring liquid enhanced the SBS between resin cement and zirconia processed with zirconia primer. In particular, colored zirconia immersed in aqueous molybdenum chloride solution showed the highest SBS. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Developing integrated workflows for the digitisation of herbarium specimens using a modular and scalable approach

PubMed Central

Haston, Elspeth; Cubey, Robert; Pullan, Martin; Atkins, Hannah; Harris, David J

2012-01-01

Abstract Digitisation programmes in many institutes frequently involve disparate and irregular funding, diverse selection criteria and scope, with different members of staff managing and operating the processes. These factors have influenced the decision at the Royal Botanic Garden Edinburgh to develop an integrated workflow for the digitisation of herbarium specimens which is modular and scalable to enable a single overall workflow to be used for all digitisation projects. This integrated workflow is comprised of three principal elements: a specimen workflow, a data workflow and an image workflow. The specimen workflow is strongly linked to curatorial processes which will impact on the prioritisation, selection and preparation of the specimens. The importance of including a conservation element within the digitisation workflow is highlighted. The data workflow includes the concept of three main categories of collection data: label data, curatorial data and supplementary data. It is shown that each category of data has its own properties which influence the timing of data capture within the workflow. Development of software has been carried out for the rapid capture of curatorial data, and optical character recognition (OCR) software is being used to increase the efficiency of capturing label data and supplementary data. The large number and size of the images has necessitated the inclusion of automated systems within the image workflow. PMID:22859881

Correlation of microstructure with dynamic deformation behavior and penetration performance of tungsten heavy alloys fabricated by mechanical alloying

NASA Astrophysics Data System (ADS)

Kim, Dong-Kuk; Lee, Sunghak; Ryu, Ho Jin; Hyunghong, Soon; Noh, Joon-Woong

2000-10-01

In this study, tungsten heavy alloy specimens were fabricated by mechanical alloying (MA), and their dynamic torsional properties and penetration performance were investigated. Dynamic torsional tests were conducted on the specimens fabricated with different sintering temperatures after MA, and then the test data were compared with those of a conventionally processed specimen. Refinement of tungsten particles was obtained after MA, but contiguity was seriously increased, thereby leading to low ductility and impact energy. Specimens in which both particle size and contiguity were simultaneously reduced by MA and two-step sintering and those having higher matrix fraction by partial MA were successfully fabricated. The dynamic test results indicated that the formation of adiabatic shear bands was expected because of the plastic localization at the central area of the gage section. Upon highspeed impact testing of these specimens, self-sharpening was promoted by the adiabatic shear band formation, but their penetration performance did not improve since much of kinetic energy of the penetrators was consumed for the microcrack formation due to interfacial debonding and cleavage fracture of tungsten particles. In order to improve penetration performance as well as to achieve selfsharpening by applying MA, conditions of MA and sintering process should be established so that alloy densification, particle refinement, and contiguity reduction can be simultaneously achieved.

Microstructure and High Temperature Mechanical Property of Fe-Cr-B Based Metal/Ceramic Composite Manufactured by Metal Injection Molding Process

NASA Astrophysics Data System (ADS)

Lee, Kee-Ahn; Gwon, Jin-Han; Yoon, Tae-Sik

2018-03-01

This study investigated the microstructure and the room and high temperature mechanical properties of Fe-Cr-B alloy manufactured by metal injection molding. In addition, hot isostatic pressing was performed to increase the density of the material, and a comparison of properties was made. Microstructural observation confirmed a bi-continuous structure composed of a three-dimensional network of α-Fe phase and (Cr,Fe)2B phase. The HIPed specimen featured a well-formed adhesion between the α-Fe phase and boride, and the number of fine pores was significantly reduced. The tensile results confirmed that the HIPed specimen (RT to 900 °C) had higher strengths compared to the as-sintered specimen, and the change of elongation starting from 700 °C was significantly greater in the HIPed specimen. Fractography suggested that cracks propagated mostly along the interface between the α-Fe matrix and boride in the as-sintered specimen, while direct fracture of boride was observed in addition to interface separation in the HIPed specimen.

CT Scans of Soil Specimen Processed in Space

NASA Technical Reports Server (NTRS)

1998-01-01

CT scans of the spcimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. This view is made from a series of horizontal slices. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: Los Alamos National Laboratory and the University of Colorado at Boulder.

Influence of Finite Element Software on Energy Release Rates Computed Using the Virtual Crack Closure Technique

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Goetze, Dirk; Ransom, Jonathon (Technical Monitor)

2006-01-01

Strain energy release rates were computed along straight delamination fronts of Double Cantilever Beam, End-Notched Flexure and Single Leg Bending specimens using the Virtual Crack Closure Technique (VCCT). Th e results were based on finite element analyses using ABAQUS# and ANSYS# and were calculated from the finite element results using the same post-processing routine to assure a consistent procedure. Mixed-mode strain energy release rates obtained from post-processing finite elem ent results were in good agreement for all element types used and all specimens modeled. Compared to previous studies, the models made of s olid twenty-node hexahedral elements and solid eight-node incompatible mode elements yielded excellent results. For both codes, models made of standard brick elements and elements with reduced integration did not correctly capture the distribution of the energy release rate acr oss the width of the specimens for the models chosen. The results suggested that element types with similar formulation yield matching results independent of the finite element software used. For comparison, m ixed-mode strain energy release rates were also calculated within ABAQUS#/Standard using the VCCT for ABAQUS# add on. For all specimens mod eled, mixed-mode strain energy release rates obtained from ABAQUS# finite element results using post-processing were almost identical to re sults calculated using the VCCT for ABAQUS# add on.

Tensile-Creep Test Specimen Preparation Practices of Surface Support Liners

NASA Astrophysics Data System (ADS)

Guner, Dogukan; Ozturk, Hasan

2017-12-01

Ground support has always been considered as a challenging issue in all underground operations. Many forms of support systems and supporting techniques are available in the mining/tunnelling industry. In the last two decades, a new polymer based material, Thin Spray-on Liner (TSL), has attained a place in the market as an alternative to the current areal ground support systems. Although TSL provides numerous merits and has different application purposes, the knowledge on mechanical properties and performance of this material is still limited. In laboratory studies, since tensile rupture is the most commonly observed failure mechanism in field applications, researchers have generally studied the tensile testing of TSLs with modification of American Society for Testing and Materials (ASTM) D-638 standards. For tensile creep testing, specimen preparation process also follows the ASTM standards. Two different specimen dimension types (Type I, Type IV) are widely preferred in TSL tensile testing that conform to the related standards. Moreover, molding and die cutting are commonly used specimen preparation techniques. In literature, there is a great variability of test results due to the difference in specimen preparation techniques and practices. In this study, a ductile TSL product was tested in order to investigate the effect of both specimen preparation techniques and specimen dimensions under 7-day curing time. As a result, ultimate tensile strength, tensile yield strength, tensile modulus, and elongation at break values were obtained for 4 different test series. It is concluded that Type IV specimens have higher strength values compared to Type I specimens and moulded specimens have lower results than that of prepared by using die cutter. Moreover, specimens prepared by molding techniques have scattered test results. Type IV specimens prepared by die cutter technique are suggested for preparation of tensile test and Type I specimens prepared by die cutter technique should be preferred for tensile creep tests.

The Effect of Hole Quality on the Fatigue Life of 2024-T3 Aluminum Alloy Sheet

NASA Technical Reports Server (NTRS)

Everett, Richard A., Jr.

2004-01-01

This paper presents the results of a study whose main objective was to determine which type of fabrication process would least affect the fatigue life of an open-hole structural detail. Since the open-hole detail is often the fundamental building block for determining the stress concentration of built-up structural parts, it is important to understand any factor that can affect the fatigue life of an open hole. A test program of constant-amplitude fatigue tests was conducted on five different sets of test specimens each made using a different hole fabrication process. Three of the sets used different mechanical drilling procedures while a fourth and fifth set were mechanically drilled and then chemically polished. Two sets of specimens were also tested under spectrum loading to aid in understanding the effects of residual compressive stresses on fatigue life. Three conclusions were made from this study. One, the residual compressive stresses caused by the hole-drilling process increased the fatigue life by two to three times over specimens that were chemically polished after the holes were drilled. Second, the chemical polishing process does not appear to adversely affect the fatigue life. Third, the chemical polishing process will produce a stress-state adjacent to the hole that has insignificant machining residual stresses.

Influence of Powder Characteristics on Processability of AlSi12 Alloy Fabricated by Selective Laser Melting

PubMed Central

Zherebtsov, Dmitry; Radionova, Ludmila

2018-01-01

Selective laser melting (SLM) is one of the additive manufacturing technologies that allows for the production of parts with complex shapes from either powder feedstock or from wires. Aluminum alloys have a great potential for use in SLM especially in automotive and aerospace fields. This paper studies the influence of starting powder characteristics on the processability of SLM fabricated AlSi12 alloy. Three different batches of gas atomized powders from different manufacturers were processed by SLM. The powders differ in particle size and its distribution, morphology and chemical composition. Cubic specimens (10 mm × 10 mm × 10 mm) were fabricated by SLM from the three different powder batches using optimized process parameters. The fabrication conditions were kept similar for the three powder batches. The influence of powder characteristics on porosity and microstructure of the obtained specimens were studied in detail. The SLM samples produced from the three different powder batches do not show any significant variations in their structural aspects. However, the microstructural aspects differ and the amount of porosity in these three specimens vary significantly. It shows that both the flowability of the powder and the apparent density have an influential role on the processability of AlSi12 SLM samples. PMID:29735932

Influence of Powder Characteristics on Processability of AlSi12 Alloy Fabricated by Selective Laser Melting.

PubMed

Baitimerov, Rustam; Lykov, Pavel; Zherebtsov, Dmitry; Radionova, Ludmila; Shultc, Alexey; Prashanth, Konda Gokuldoss

2018-05-07

Selective laser melting (SLM) is one of the additive manufacturing technologies that allows for the production of parts with complex shapes from either powder feedstock or from wires. Aluminum alloys have a great potential for use in SLM especially in automotive and aerospace fields. This paper studies the influence of starting powder characteristics on the processability of SLM fabricated AlSi12 alloy. Three different batches of gas atomized powders from different manufacturers were processed by SLM. The powders differ in particle size and its distribution, morphology and chemical composition. Cubic specimens (10 mm × 10 mm × 10 mm) were fabricated by SLM from the three different powder batches using optimized process parameters. The fabrication conditions were kept similar for the three powder batches. The influence of powder characteristics on porosity and microstructure of the obtained specimens were studied in detail. The SLM samples produced from the three different powder batches do not show any significant variations in their structural aspects. However, the microstructural aspects differ and the amount of porosity in these three specimens vary significantly. It shows that both the flowability of the powder and the apparent density have an influential role on the processability of AlSi12 SLM samples.

An optimized work-flow to reduce time-to-detection of carbapenemase-producing Enterobacteriaceae (CPE) using direct testing from rectal swabs.

PubMed

O'Connor, C; Kiernan, M G; Finnegan, C; O'Hara, M; Power, L; O'Connell, N H; Dunne, C P

2017-05-04

Rapid detection of patients with carbapenemase-producing Enterobacteriaceae (CPE) is essential for the prevention of nosocomial cross-transmission, allocation of isolation facilities and to protect patient safety. Here, we aimed to design a new laboratory work-flow, utilizing existing laboratory resources, in order to reduce time-to-diagnosis of CPE. A review of the current CPE testing processes and of the literature was performed to identify a real-time commercial polymerase chain reaction (PCR) assay that could facilitate batch testing of CPE clinical specimens, with adequate CPE gene coverage. Stool specimens (210) were collected; CPE-positive inpatients (n = 10) and anonymized community stool specimens (n = 200). Rectal swabs (eSwab™) were inoculated from collected stool specimens and a manual DNA extraction method (QIAamp® DNA Stool Mini Kit) was employed. Extracted DNA was then processed on the Check-Direct CPE® assay. The three step process of making the eSwab™, extracting DNA manually and running the Check-Direct CPE® assay, took <5 min, 1 h 30 min and 1 h 50 min, respectively. It was time efficient with a result available in under 4 h, comparing favourably with the existing method of CPE screening; average time-to-diagnosis of 48/72 h. Utilizing this CPE work-flow would allow a 'same-day' result. Antimicrobial susceptibility testing results, as is current practice, would remain a 'next-day' result. In conclusion, the Check-Direct CPE® assay was easily integrated into a local laboratory work-flow and could facilitate a large volume of CPE screening specimens in a single batch, making it cost-effective and convenient for daily CPE testing.

Confusion—specimen mix-up in dermatopathology and measures to prevent and detect it

PubMed Central

Weyers, Wolfgang

2014-01-01

Maintaining patient identity throughout the biopsy pathway is critical for the practice of dermatology and dermatopathology. From the biopsy procedure to the acquisition of the pathology report, a specimen may pass through the hands of more than twenty individuals in several workplaces. The risk of a mix-up is considerable and may account for more serious mistakes than diagnostic errors. To prevent specimen mix-up, work processes should be standardized and automated wherever possible, e.g., by strict order in the operating room and in the laboratory and by adoption of a bar code system to identify specimens and corresponding request forms. Mutual control of clinicians, technicians, histopathologists, and secretaries, both simultaneously and downstream, is essential to detect errors. The most vulnerable steps of the biopsy pathway, namely, labeling of specimens and request forms and accessioning of biopsy specimens in the laboratory, should be carried out by two persons simultaneously. In preceding work steps, clues must be provided that allow a mix-up to be detected later on, such as information about clinical diagnosis, biopsy technique, and biopsy site by the clinician, and a sketch of the specimen by the technician grossing it. Awareness of the danger of specimen mix-up is essential for preventing and detecting it. The awareness can be heightened by documentation of any error in the biopsy pathway. In case of suspicion, a mix-up of specimens from different patients can be confirmed by DNA analysis. PMID:24520511

Confusion-specimen mix-up in dermatopathology and measures to prevent and detect it.

PubMed

Weyers, Wolfgang

2014-01-01

Maintaining patient identity throughout the biopsy pathway is critical for the practice of dermatology and dermatopathology. From the biopsy procedure to the acquisition of the pathology report, a specimen may pass through the hands of more than twenty individuals in several workplaces. The risk of a mix-up is considerable and may account for more serious mistakes than diagnostic errors. To prevent specimen mix-up, work processes should be standardized and automated wherever possible, e.g., by strict order in the operating room and in the laboratory and by adoption of a bar code system to identify specimens and corresponding request forms. Mutual control of clinicians, technicians, histopathologists, and secretaries, both simultaneously and downstream, is essential to detect errors. The most vulnerable steps of the biopsy pathway, namely, labeling of specimens and request forms and accessioning of biopsy specimens in the laboratory, should be carried out by two persons simultaneously. In preceding work steps, clues must be provided that allow a mix-up to be detected later on, such as information about clinical diagnosis, biopsy technique, and biopsy site by the clinician, and a sketch of the specimen by the technician grossing it. Awareness of the danger of specimen mix-up is essential for preventing and detecting it. The awareness can be heightened by documentation of any error in the biopsy pathway. In case of suspicion, a mix-up of specimens from different patients can be confirmed by DNA analysis.

Interface morphology and mechanical properties of Al-Cu-Al laminated composites fabricated by explosive welding and subsequent rolling process

NASA Astrophysics Data System (ADS)

Hoseini-Athar, M. M.; Tolaminejad, B.

2016-07-01

Explosive welding is a well-known solid state method for joining similar and dissimilar materials. In the present study, tri-layered Al-Cu-Al laminated composites with different interface morphologies were fabricated by explosive welding and subsequent rolling. Effects of explosive ratio and rolling thickness reduction on the morphology of interface and mechanical properties were evaluated through optical/scanning electron microscopy, micro-hardness, tensile and tensile-shear tests. Results showed that by increasing the thickness reduction, bonding strength of specimens including straight and wavy interfaces increases. However, bonding strength of the specimens with melted layer interface decreases up to a threshold thickness reduction, then rapidly increases by raising the reduction. Hardness Values of welded specimens were higher than those of original material especially near the interface and a more uniform hardness profile was obtained after rolling process.

Multiparameter magnetic inspection system with magnetic field control and plural magnetic transducers

DOEpatents

Jiles, D.C.

1991-04-16

A multiparameter magnetic inspection system is disclosed for providing an efficient and economical way to derive a plurality of independent measurements regarding magnetic properties of the magnetic material under investigation. The plurality of transducers for a plurality of different types of measurements operatively connected to the specimen. The transducers are in turn connected to analytical circuits for converting transducer signals to meaningful measurement signals of the magnetic properties of the specimen. The measurement signals are processed and can be simultaneously communicated to a control component. The measurement signals can also be selectively plotted against one another. The control component operates the functioning of the analytical circuits and operates and controls components to impose magnetic fields of desired characteristics upon the specimen. The system therefore allows contemporaneous or simultaneous derivation of the plurality of different independent magnetic properties of the material which can then be processed to derive characteristics of the material. 1 figure.

Monitoring small-crack growth by the replication method

NASA Technical Reports Server (NTRS)

Swain, Mary H.

1992-01-01

The suitability of the acetate replication method for monitoring the growth of small cracks is discussed. Applications of this technique are shown for cracks growing at the notch root in semicircular-edge-notch specimens of a variety of aluminum alloys and one steel. The calculated crack growth rate versus Delta K relationship for small cracks was compared to that for large cracks obtained from middle-crack-tension specimens. The primary advantage of this techinque is that it provides an opportunity, at the completion of the test, to go backward in time towards the crack initiation event and 'zoom in' on areas of interest on the specimen surface with a resolution of about 0.1 micron. The primary disadvantage is the inability to automate the process. Also, for some materials, the replication process may alter the crack-tip chemistry or plastic zone, thereby affecting crack growth rates.

Processing of Cryo-EM Movie Data.

PubMed

Ripstein, Z A; Rubinstein, J L

2016-01-01

Direct detector device (DDD) cameras dramatically enhance the capabilities of electron cryomicroscopy (cryo-EM) due to their improved detective quantum efficiency (DQE) relative to other detectors. DDDs use semiconductor technology that allows micrographs to be recorded as movies rather than integrated individual exposures. Movies from DDDs improve cryo-EM in another, more surprising, way. DDD movies revealed beam-induced specimen movement as a major source of image degradation and provide a way to partially correct the problem by aligning frames or regions of frames to account for this specimen movement. In this chapter, we use a self-consistent mathematical notation to explain, compare, and contrast several of the most popular existing algorithms for computationally correcting specimen movement in DDD movies. We conclude by discussing future developments in algorithms for processing DDD movies that would extend the capabilities of cryo-EM even further. © 2016 Elsevier Inc. All rights reserved.

Multiparameter magnetic inspection system with magnetic field control and plural magnetic transducers

DOEpatents

Jiles, David C.

1991-04-16

A multiparameter magnetic inspection system for providing an efficient and economical way to derive a plurality of independent measurements regarding magnetic properties of the magnetic material under investigation. The plurality of transducers for a plurality of different types of measurements operatively connected to the specimen. The transducers are in turn connected to analytical circuits for converting transducer signals to meaningful measurement signals of the magnetic properties of the specimen. The measurement signals are processed and can be simultaneously communicated to a control component. The measurement signals can also be selectively plotted against one another. The control component operates the functioning of the analytical circuits and operates and controls components to impose magnetic fields of desired characteristics upon the specimen. The system therefore allows contemporaneous or simultaneous derivation of the plurality of different independent magnetic properties of the material which can then be processed to derive characteristics of the material.

Mechanical properties of micro-injected HDPE composites

NASA Astrophysics Data System (ADS)

Bongiorno, A.; Pagano, C.; Agnelli, S.; Baldi, F.; Fassi, I.

2016-03-01

Micro-injection moulding is one of the key manufacturing technologies for the mass production of high value polymeric miniaturized-components. However, this process is not just a straightforward down scaling of the conventional injection moulding technique. Indeed, during the micro-injection the polymer melt is forced to flow at high strain rates through very small channels in non-isothermal conditions, and this can lead to complex microstructures and to parts with unexpected performances. In this work, the relationships among the processing conditions, the mechanical properties and the microstructural characteristics of miniaturized specimens obtained by injection moulding were investigated. Two model systems were considered with the same filler content of 15% wt. (HDPE-talc and HDPE-glass beads), representative of two different types of micro-composites: containing lamellar and spherical micro-particles, respectively. The attention was focused on the influence of the filler type and the process conditions on the mechanical behaviour, examined by uniaxial tensile tests and dynamic-mechanical analyses, and on the morphological characteristics of the specimens, examined by microscopy analyses. The results highlight that mechanical response of the miniaturized specimens is significantly affected by both the filler and the process conditions that can have an influence on the polymer microstructure. Lamellar composites showed the best performance due to the orientation of the talc particles during the micro-injection process, while, different morphologies of the skin/core transition region in dependence on the process temperatures were observable.

Investigation of interfacial fracture behavior on injection molded parts

NASA Astrophysics Data System (ADS)

Fischer, Matthieu; Ausias, Gilles; Kuehnert, Ines

2016-03-01

In this study the interfacial morphology of different polymers joined by various assembly injection molding (AIM) technologies were discussed. Melt streams were injected successively using tools with core-back or rotation techniques. To compare bulk specimen strength and weld line strength, the fracture behavior of different specimen scales and thin sections were investigated. An in-situ SEM tensile test and a new thin section testing device which is used in polarized (transmitted) light microscopy were used to observe specimen failure. The effects of processing on spherulitic structures were linked to bonding strength and mechanical properties.

Artifacts in magnetic spirals retrieved by transport of intensity equation (TIE)

NASA Astrophysics Data System (ADS)

Cui, J.; Yao, Y.; Shen, X.; Wang, Y. G.; Yu, R. C.

2018-05-01

The artifacts in the magnetic structures reconstructed from Lorentz transmission electron microscopy (LTEM) images with TIE method have been analyzed in detail. The processing for the simulated images of Bloch and Neel spirals indicated that the improper parameters in TIE may overestimate the high frequency information and induce some false features in the retrieved images. The specimen tilting will further complicate the analysis of the images because the LTEM image contrast is not the result of the magnetization distribution within the specimen but the integral projection pattern of the magnetic induction filling the entire space including the specimen.

Proposal of a punch biopsy protocol as a pre-requisite for the establishment of a tissue bank from resected esophageal tumors.

PubMed

Bonavina, Luigi; Laface, Letizia; Picozzi, Stefano; Nencioni, Marco; Siboni, Stefano; Bona, Davide; Sironi, Andrea; Sorba, Francesca; Clemente, Claudio

2010-09-01

With the development of tissue banking, a need for homogeneous methods of collection, processing, and storage of tissue has emerged. We describe the implementation of a biological bank in a high-volume, tertiary care University referral center for esophageal cancer surgery. We also propose an original punch biopsy technique of the surgical specimen. The method proved to be simple, reproducible, and not expensive. Unified standards for specimen collection are necessary to improve results of specimen-based diagnostic testing and research in surgical oncology.

Technique for restoration of mite (Acari) preparations in deteriorated Hoyer's medium.

PubMed

Jacinavicius, F C; Badari, J C; Ramirez, D G; Moraes, R H P; Onofrio, V C; Barros-Battesti, D M

2013-06-01

The Acari Collection of Instituto Butantan (IBSP), São Paulo, Brazil, includes many types and other identified mite specimens that were mounted in Hoyer's medium, mainly in the first part of last century. An effort to restore degraded preparations was initiated in 1996. In this process, an improved technique was developed, allowing the adequate cleaning of specimens mounted up to 50-70 years before. Types and other identified specimens of Trombidiformes (Harpirhynchidae and Trombiculidae), Sarcoptiformes (Acaridae, Atopomelidae, Listrophoridae, and Psoroptidae) and Mesostigmata (Dermanyssidae, Ixodorhynchidae, Laelapidae, Macronyssidae, and Spinturnicidae) deposited at IBSP Collection have been satisfactorily restored.

[Establishment and Management of Multiple Myeloma Specimen Bank Applied for Molecular Biological Researches].

PubMed

Li, Han-Qing; Mei, Jian-Gang; Cao, Hong-Qin; Shao, Liang-Jing; Zhai, Yong-Ping

2017-12-01

To establish a multiple myeloma specimen bank applied for molecular biological researches and to explore the methods of specimen collection, transportation, storage, quality control and the management of specimen bank. Bone marrow and blood samples were collected from multiple myeloma patients, plasma cell sorting were operated after the separation of mononuclear cells from bone marrow specimens. The plasma cells were divided into 2 parts, one was added with proper amount of TRIzol and then kept in -80 °C refrigerator for subsequent RNA extraction, the other was added with proper amount of calf serum cell frozen liquid and then kept in -80 °C refrigerator for subsequent cryopreservation of DNA extraction after numbered respectively. Serum and plasma were separated from peripheral blood, specimens of serum and plasma were then stored at -80 °C refrigerator after registration. Meantime, the myeloma specimen information management system was established, managed and maintained by specially-assigned persons and continuous modification and improvement in the process of use as to facilitate the rapid collection, management, query of the effective samples and clinical data. A total of 244 portions plasma cells, 564 portions of serum, and 1005 portions of plasma were collected, clinical characters were documented. A multiple myeloma specimen bank have been established initially, which can provide quality samples and related clinical information for molecular biological research on multiple myeloma.

An Upgrade Pinning Block: A Mechanical Practical Aid for Fast Labelling of the Insect Specimens.

PubMed

Ghafouri Moghaddam, Mohammad Hossein; Ghafouri Moghaddam, Mostafa; Rakhshani, Ehsan; Mokhtari, Azizollah

2017-01-01

A new mechanical innovation is described to deal with standard labelling of dried specimens on triangular cards and/or pinned specimens in personal and public collections. It works quickly, precisely, and easily and is very useful for maintaining label uniformity in collections. The tools accurately sets the position of labels in the shortest possible time. This tools has advantages including rapid processing, cost effectiveness, light weight, and high accuracy, compared to conventional methods. It is fully customisable, compact, and does not require specialist equipment to assemble. Conventional methods generally require locating holes on the pinning block surface when labelling with a resulting risk to damage of the specimens. Insects of different orders can be labelled by this simple and effective tool.

An Upgrade Pinning Block: A Mechanical Practical Aid for Fast Labelling of the Insect Specimens

PubMed Central

Ghafouri Moghaddam, Mohammad Hossein; Rakhshani, Ehsan; Mokhtari, Azizollah

2017-01-01

Abstract A new mechanical innovation is described to deal with standard labelling of dried specimens on triangular cards and/or pinned specimens in personal and public collections. It works quickly, precisely, and easily and is very useful for maintaining label uniformity in collections. The tools accurately sets the position of labels in the shortest possible time. This tools has advantages including rapid processing, cost effectiveness, light weight, and high accuracy, compared to conventional methods. It is fully customisable, compact, and does not require specialist equipment to assemble. Conventional methods generally require locating holes on the pinning block surface when labelling with a resulting risk to damage of the specimens. Insects of different orders can be labelled by this simple and effective tool. PMID:29104440

Characteristic of Low Temperature Carburized Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Istiroyah; Pamungkas, M. A.; Saroja, G.; Ghufron, M.; Juwono, A. M.

2018-01-01

Low temperature carburizing process has been carried out on austenitic stainless steel (ASS) type AISI 316L, that contain chromium in above 12 at%. Therefore, conventional heat treatment processes that are usually carried out at high temperatures are not applicable. The sensitization process due to chromium migration from the grain boundary will lead to stress corrosion crack and decrease the corrosion resistance of the steel. In this study, the carburizing process was carried out at low temperatures below 500 °C. Surface morphology and mechanical properties of carburized specimens were investigated using optical microscopy, non destructive profilometer, and Vicker microhardness. The surface roughness analysis show the carburising process improves the roughness of ASS surface. This improvement is due to the adsorption of carbon atoms on the surface of the specimen. Likewise, the hardness test results indicate the carburising process increases the hardness of ASS.

Development of high temperature containerless processing equipment and the design and evaluation of associated systems required for microgravity materials processing and property measurements

NASA Technical Reports Server (NTRS)

Rey, Charles A.

1991-01-01

The development of high temperature containerless processing equipment and the design and evaluation of associated systems required for microgravity materials processing and property measurements are discussed. Efforts were directed towards the following task areas: design and development of a High Temperature Acoustic Levitator (HAL) for containerless processing and property measurements at high temperatures; testing of the HAL module to establish this technology for use as a positioning device for microgravity uses; construction and evaluation of a brassboard hot wall Acoustic Levitation Furnace; construction and evaluation of a noncontact temperature measurement (NCTM) system based on AGEMA thermal imaging camera; construction of a prototype Division of Amplitude Polarimetric Pyrometer for NCTM of levitated specimens; evaluation of and recommendations for techniques to control contamination in containerless materials processing chambers; and evaluation of techniques for heating specimens to high temperatures for containerless materials experimentation.

Development of high temperature containerless processing equipment and the design and evaluation of associated systems required for microgravity materials processing and property measurements

NASA Astrophysics Data System (ADS)

Rey, Charles A.

1991-03-01

The development of high temperature containerless processing equipment and the design and evaluation of associated systems required for microgravity materials processing and property measurements are discussed. Efforts were directed towards the following task areas: design and development of a High Temperature Acoustic Levitator (HAL) for containerless processing and property measurements at high temperatures; testing of the HAL module to establish this technology for use as a positioning device for microgravity uses; construction and evaluation of a brassboard hot wall Acoustic Levitation Furnace; construction and evaluation of a noncontact temperature measurement (NCTM) system based on AGEMA thermal imaging camera; construction of a prototype Division of Amplitude Polarimetric Pyrometer for NCTM of levitated specimens; evaluation of and recommendations for techniques to control contamination in containerless materials processing chambers; and evaluation of techniques for heating specimens to high temperatures for containerless materials experimentation.

Energy-absorption capability of composite tubes and beams. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Farley, Gary L.; Jones, Robert M.

1989-01-01

In this study the objective was to develop a method of predicting the energy-absorption capability of composite subfloor beam structures. Before it is possible to develop such an analysis capability, an in-depth understanding of the crushing process of composite materials must be achieved. Many variables affect the crushing process of composite structures, such as the constituent materials' mechanical properties, specimen geometry, and crushing speed. A comprehensive experimental evaluation of tube specimens was conducted to develop insight into how composite structural elements crush and what are the controlling mechanisms. In this study the four characteristic crushing modes, transverse shearing, brittle fracturing, lamina bending, and local buckling were identified and the mechanisms that control the crushing process defined. An in-depth understanding was developed of how material properties affect energy-absorption capability. For example, an increase in fiber and matrix stiffness and failure strain can, depending upon the configuration of the tube, increase energy-absorption capability. An analysis to predict the energy-absorption capability of composite tube specimens was developed and verified. Good agreement between experiment and prediction was obtained.

Shear Strength and Cracking Process of Non-persistent Jointed Rocks: An Extensive Experimental Investigation

NASA Astrophysics Data System (ADS)

Asadizadeh, Mostafa; Moosavi, Mahdi; Hossaini, Mohammad Farouq; Masoumi, Hossein

2018-02-01

In this paper, a number of artificial rock specimens with two parallel (stepped and coplanar) non-persistent joints were subjected to direct shearing. The effects of bridge length ( L), bridge angle ( γ), joint roughness coefficient (JRC) and normal stress ( σ n) on shear strength and cracking process of non-persistent jointed rock were studied extensively. The experimental program was designed based on Taguchi method, and the validity of the resulting data was assessed using analysis of variance. The results revealed that σ n and γ have the maximum and minimum effects on shear strength, respectively. Also, increase in L from 10 to 60 mm led to decrease in shear strength where high level of JRC profile and σ n led to the initiation of tensile cracks due to asperity interlocking. Such tensile cracks are known as "interlocking cracks" which normally initiate from the asperity and then propagate toward the specimen boundaries. Finally, the cracking process of specimens was classified into three categories, namely tensile cracking, shear cracking and combination of tension and shear or mixed mode tensile-shear cracking.

Using NIR spectroscopy to predict weathered wood exposure times

Treesearch

Xiping Wang; James P. Wacker

2006-01-01

This poster presentation reports on recent laboratory work aimed at quantifying the biodegradation process of wood during exposure to natural weathering. Approximately 330 southern pine lumber specimens were placed “above-ground” at an outdoor exposure site near Gulfport, Mississippi for periods up to five years. An additional 90 specimens were stored indoor to serve...

National Aeronautics and Space Administration Biological Specimen Repository

NASA Technical Reports Server (NTRS)

McMonigal, Kathleen A.; Pietrzyk, Robert a.; Johnson, Mary Anne

2008-01-01

The National Aeronautics and Space Administration Biological Specimen Repository (Repository) is a storage bank that is used to maintain biological specimens over extended periods of time and under well-controlled conditions. Samples from the International Space Station (ISS), including blood and urine, will be collected, processed and archived during the preflight, inflight and postflight phases of ISS missions. This investigation has been developed to archive biosamples for use as a resource for future space flight related research. The International Space Station (ISS) provides a platform to investigate the effects of microgravity on human physiology prior to lunar and exploration class missions. The storage of crewmember samples from many different ISS flights in a single repository will be a valuable resource with which researchers can study space flight related changes and investigate physiological markers. The development of the National Aeronautics and Space Administration Biological Specimen Repository will allow for the collection, processing, storage, maintenance, and ethical distribution of biosamples to meet goals of scientific and programmatic relevance to the space program. Archiving of the biosamples will provide future research opportunities including investigating patterns of physiological changes, analysis of components unknown at this time or analyses performed by new methodologies.

Titanium honeycomb acoustic lining structural and thermal test report. [for acoustic tailpipe for JT8D engine

NASA Technical Reports Server (NTRS)

Joynes, D.; Balut, J. P.

1974-01-01

The results are presented of static, fatigue and thermal testing of titanium honeycomb acoustic panels representing the acoustic tailpipe for the Pratt and Whitney Aircraft JT8D Refan engine which is being studied for use on the Boeing 727-200 airplane. Test specimens represented the engine and tailpipe flange joints, the rail to which the thrust reverser is attached and shear specimens of the tailpipe honeycomb. Specimens were made in four different batches with variations in configuration, materials and processes in each. Static strength of all test specimens exceeded the design ultimate load requirements. Fatigue test results confirmed that aluminum brazed titanium, as used in the Refan tailpipe design, meets the fatigue durability objectives. Quality of welding was found to be critical to life, with substandard welding failing prematurely, whereas welding within the process specification exceeded the panel skin life. Initial fatigue testing used short grip length bolts which failed prematurely. These were replaced with longer bolts and subsequent testing demonstrated the required life. Thermal tests indicate that perforated skin acoustic honeycomb has approximately twice the heat transfer of solid skin honeycomb.

Development of Processing Techniques for Advanced Thermal Protection Materials

NASA Technical Reports Server (NTRS)

Selvaduray, Guna; Cox, Michael; Srinivasan, Vijayakumar

1997-01-01

Thermal Protection Materials Branch (TPMB) has been involved in various research programs to improve the properties and structural integrity of the existing aerospace high temperature materials. Specimens from various research programs were brought into the analytical laboratory for the purpose of obtaining and refining the material characterization. The analytical laboratory in TPMB has many different instruments which were utilized to determine the physical and chemical characteristics of materials. Some of the instruments that were utilized by the SJSU students are: Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX), X-ray Diffraction Spectrometer (XRD), Fourier Transform-Infrared Spectroscopy (FTIR), Ultra Violet Spectroscopy/Visible Spectroscopy (UV/VIS), Particle Size Analyzer (PSA), and Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES). The above mentioned analytical instruments were utilized in the material characterization process of the specimens from research programs such as: aerogel ceramics (I) and (II), X-33 Blankets, ARC-Jet specimens, QUICFIX specimens and gas permeability of lightweight ceramic ablators. In addition to analytical instruments in the analytical laboratory at TPMB, there are several on-going experiments. One particular experiment allows the measurement of permeability of ceramic ablators. From these measurements, physical characteristics of the ceramic ablators can be derived.

Reinforced Carbon Carbon (RCC) oxidation resistant material samples - Baseline coated, and baseline coated with tetraethyl orthosilicate (TEOS) impregnation

NASA Technical Reports Server (NTRS)

Gantz, E. E.

1977-01-01

Reinforced carbon-carbon material specimens were machined from 19 and 33 ply flat panels which were fabricated and processed in accordance with the specifications and procedures accepted for the fabrication and processing of the leading edge structural subsystem (LESS) elements for the space shuttle orbiter. The specimens were then baseline coated and tetraethyl orthosilicate impregnated, as applicable, in accordance with the procedures and requirements of the appropriate LESS production specifications. Three heater bars were ATJ graphite silicon carbide coated with the Vought 'pack cementation' coating process, and three were stackpole grade 2020 graphite silicon carbide coated with the chemical vapor deposition process utilized by Vought in coating the LESS shell development program entry heater elements. Nondestructive test results are reported.

Specimen Designs for Testing Advanced Aeropropulsion Materials Under In-Plane Biaxial Loading

NASA Technical Reports Server (NTRS)

Ellis, John R.; Abul-Aziz, Ali

2003-01-01

A design study was undertaken to develop specimen designs for testing advanced aeropropulsion materials under in-plane biaxial loading. The focus of initial work was on developing a specimen design suitable for deformation and strength tests to be conducted under monotonic loading. The type of loading initially assumed in this study was the special case of equibiaxial, tensile loading. A specimen design was successfully developed after a lengthy design and optimization process with overall dimensions of 12 by 12 by 0.625 in., and a gage area of 3.875 by 3.875 by 0.080 in. Subsequently, the scope of the work was extended to include the development of a second design tailored for tests involving cyclic loading. A specimen design suitably tailored to meet these requirements was successfully developed with overall dimensions of 12 by 12 by 0.500 in. and a gage area of 2.375 by 2.375 by 0.050 in. Finally, an investigation was made to determine whether the specimen designs developed in this study for equibiaxial, tensile loading could be used without modification to investigate general forms of biaxial loading. For best results, it was concluded that specimen designs need to be optimized and tailored to meet the specific loading requirements of individual research programs.

Birds of Antioquia: Georeferenced database of specimens from the Colección de Ciencias Naturales del Museo Universitario de la Universidad de Antioquia (MUA).

PubMed

Rozo, Andrea Morales; Valencia, Fernando; Acosta, Alexis; Parra, Juan Luis

2014-01-01

The department of Antioquia, Colombia, lies in the northwestern corner of South America and provides a biogeographical link among divergent faunas, including Caribbean, Andean, Pacific and Amazonian. Information about the distribution of biodiversity in this area is of relevance for academic, practical and social purposes. This data paper describes the dataset containing all bird specimens deposited in the Colección de Ciencias Naturales del Museo Universitario de la Universidad de Antioquia (MUA). We curated all the information associated with the bird specimens, including the georeferences and taxonomy, and published the database through the Global Biodiversity Information Facility network. During this process we checked the species identification and existing georeferences and completed the information when possible. The collection holds 663 bird specimens collected between 1940 and 2011. Even though most specimens are from Antioquia (70%), the collection includes material from several other departments and one specimen from the United States. The collection holds specimens from three endemic and endangered species (Coeligena orina, Diglossa gloriossisima, and Hypopirrhus pyrohipogaster), and includes localities poorly represented in other collections. The information contained in the collection has been used for biodiversity modeling, conservation planning and management, and we expect to further facilitate these activities by making it publicly available.

Modelling of the mechanical behaviour of the single-crystal turbine alloy CMSX-4 during thermomechanical loading

NASA Astrophysics Data System (ADS)

Schubert, F.; Fleury, G.; Steinhaus, T.

2000-11-01

Turbine blades in gas turbine engines are subjected during operation to triaxial stress fields. For the description of the deformation behaviour of anisotropic single-crystal blades, constitutive equations are required which take account of modifications to the deformation processes caused by evolution of the γ/γ' microstructure during service (γ' rafting). A microstructure-dependent, orthotropic Hills potential, whose anisotropy coefficients are connected to the edge length of γ' particles, has been applied. The shape of γ' particles remains cubic below exposures at 700 °C. At high temperatures (above 850 °C) the γ' particles coalesce to rafts, and the viscoplastic response of the superalloy is continuously modified. This reduces the creep resistance of <001> orientated specimen. After tensile loading of the <001>-orientated specimens at 1000 °C, the rafting of γ' in the (100) plane was observed as expected, whereas the <111> specimens did not reveal γ' rafting. Torsionally loaded specimens exhibited rafting only in the near <100>-orientated surface regions of the specimen. The deformation in the <111> tensile and <001> torsion specimens occurred by octahedral slip of dislocations and not by cubic slip, as expected from theoretical considerations. Rafting did not occur in the <111>-orientated specimens. This anisotropy change is simulated successfully by the microstructure-dependent model.

Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber.

PubMed

Nguyen, Kayla X; Holtz, Megan E; Richmond-Decker, Justin; Muller, David A

2016-08-01

A long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope's objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Monte Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400 μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens and in situ chemical and electrochemical processes.

Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Kayla X.; Holtz, Megan E.; Richmond-Decker, Justin

2016-07-25

Abstract A long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope’s objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Montemore » Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens andin situchemical and electrochemical processes.« less

Evaluation of tensile bond strength of heat cure and autopolymerizing silicone-based resilient denture liners before and after thermocycling.

PubMed

Madan, Nishtha; Datta, Kusum

2012-01-01

To assess the effect of simulated mouth conditions reproduced with thermocycling on the tensile bond strength of two silicone based resilient denture liners with acrylic resin bases. Two silicone-based soft denture liners (Mollosil - Chairside autopolymerization and Molloplast B - Heat polymerization) were tested. For each liner, 30 specimens with a cross-sectional area of 10 Χ 10 mm and thickness 3 mm were processed between two acrylic blocks (Trevalon). Specimens were divided into a control group that was stored for 24 hours in water at 37°C and a test group that was thermocycled (2500 cycles) between baths of 5° and 55°C. Tensile bond strength (kg/cm²) was determined in a universal testing machine using crosshead speed of 5 mm/min. The student t-test was used to determine the significance of the difference in bond strength between the two liners. The mean tensile bond strength for control and thermocycled specimens of the two liners were: Mollosil (6.82 kg/cm² and 8.41 kg/cm²) and Molloplast-B (16.30 kg/cm² and 13.67 kg/cm²), respectively. Comparison of bond strength of control specimens with thermocycled specimens of the liners indicated a significant difference for both Mollosil (P=0.045) and Molloplast-B (P=0.027). Comparison between control specimens of both liners and thermocycled specimens of both liners indicated a highly significant difference (P<0.001). Heat polymerized resilient denture liner Molloplast-B had higher tensile bond strength than autopolymerizing liner Mollosil regardless of thermocycling. The bond strength of Mollosil increased after thermocycling while that of Molloplast-B decreased after thermocycling. Although heat-polymerized denture liners require more processing time than autopolymerizing liners, but they display much better adhesion properties to denture base resin and should thus be preferred when soft liner has to be used for a longer duration of time.

Predicting fracture of mortar beams under three-point bending using non-extensive statistical modeling of electric emissions

NASA Astrophysics Data System (ADS)

Stergiopoulos, Ch.; Stavrakas, I.; Triantis, D.; Vallianatos, F.; Stonham, J.

2015-02-01

Weak electric signals termed as 'Pressure Stimulated Currents, PSC' are generated and detected while cement based materials are found under mechanical load, related to the creation of cracks and the consequent evolution of cracks' network in the bulk of the specimen. During the experiment a set of cement mortar beams of rectangular cross-section were subjected to Three-Point Bending (3PB). For each one of the specimens an abrupt mechanical load step was applied, increased from the low load level (Lo) to a high final value (Lh) , where Lh was different for each specimen and it was maintained constant for long time. The temporal behavior of the recorded PSC show that during the load increase a spike-like PSC emission was recorded and consequently a relaxation of the PSC, after reaching its final value, follows. The relaxation process of the PSC was studied using non-extensive statistical physics (NESP) based on Tsallis entropy equation. The behavior of the Tsallis q parameter was studied in relaxation PSCs in order to investigate its potential use as an index for monitoring the crack evolution process with a potential use in non-destructive laboratory testing of cement-based specimens of unknown internal damage level. The dependence of the q-parameter on the Lh (when Lh <0.8Lf), where Lf represents the 3PB strength of the specimen, shows an increase on the q value when the specimens are subjected to gradually higher bending loadings and reaches a maximum value close to 1.4 when the applied Lh becomes higher than 0.8Lf. While the applied Lh becomes higher than 0.9Lf the value of the q-parameter gradually decreases. This analysis of the experimental data manifests that the value of the entropic index q obtains a characteristic decrease while reaching the ultimate strength of the specimen, and thus could be used as a forerunner of the expected failure.

Effects of the Heterogeneity in the Electron Beam Welded Joint on Mechanical Properties of Ti6Al4V Alloy

NASA Astrophysics Data System (ADS)

Liu, Jing; Gao, Xiao-Long; Zhang, Lin-Jie; Zhang, Jian-Xun

2015-01-01

The aim of this investigation was to evaluate the effect of microstructure heterogeneity on the tensile and low cycle fatigue properties of electron beam welded (EBW) Ti6Al4V sheets. To achieve this goal, the tensile and low cycle fatigue property in the EBW joints and base metal (BM) specimens is compared. During the tensile testing, digital image correlation technology was used to measure the plastic strain field evolution within the specimens. The experimental results showed that the tensile ductility and low cycle fatigue strength of EBW joints are lower than that of BM specimens, mainly because of the effect of microstructure heterogeneity of the welded joint. Moreover, the EBW joints exhibit the cyclic hardening behavior during low fatigue process, while BM specimens exhibit the cyclic softening behavior. Compared with the BM specimens with uniform microstructure, the heterogeneity of microstructure in the EBW joint is found to decrease the mechanical properties of welded joint.

Finite element analysis of the end notched flexure specimen for measuring Mode II fracture toughness

NASA Technical Reports Server (NTRS)

Gillespie, J. W., Jr.; Carlsson, L. A.; Pipes, R. B.

1986-01-01

The paper presents a finite element analysis of the end-notched flexure (ENF) test specimen for Mode II interlaminar fracture testing of composite materials. Virtual crack closure and compliance techniques employed to calculate strain energy release rates from linear elastic two-dimensional analysis indicate that the ENF specimen is a pure Mode II fracture test within the constraints of small deflection theory. Furthermore, the ENF fracture specimen is shown to be relatively insensitive to process-induced cracks, offset from the laminate midplane. Frictional effects are investigated by including the contact problem in the finite element model. A parametric study investigating the influence of delamination length, span, thickness, and material properties assessed the accuracy of beam theory expressions for compliance and strain energy release rate, GII. Finite element results indicate that data reduction schemes based upon beam theory underestimate GII by approximately 20-40 percent for typical unidirectional graphite fiber composite test specimen geometries. Consequently, an improved data reduction scheme is proposed.

Flaw growth of 7075, 7475, 7050 and 7049 aluminum alloy plate in stress corrosion environments

NASA Technical Reports Server (NTRS)

Dorward, R. C.; Hasse, K. R.

1976-01-01

Marine atmosphere and laboratory stress corrosion test results on smooth and precracked specimens from 7075, 7475, 7050, and 7049 alloy plates (1.25 and 3.0-in. thick) are presented. It is shown that for a given strength level, alloys 7050-T7X and 7049-T7X have superior short-transverse stress corrosion resistance (SCR) to 7X75-T7X. At typical strength levels above the minimum, for example, SCR of these alloys is considerably better than that of 7075-T76, and approaches that of 7075-T73. Alloy 7475 maintains an advantage in the area of fracture toughness, however, because it can be thermally processed to give particularly clean microstructures. Results from precracked specimens are in good qualitative agreement with those obtained from smooth specimens. Although both specimen types are capable of distinguishing between -T6, -T76 and -T73 tempers in relatively short time periods the precracked specimen provides more information about crack growth rates.

Rapid virtual H&E histology of breast tissue specimens using a compact fluorescence nonlinear microscope

PubMed Central

Cahill, Lucas C.; Giacomelli, Michael G.; Yoshitake, Tadayuki; Vardeh, Hilde; Faulkner-Jones, Beverly E.; Connolly, James L.; Sun, Chi-Kuang; Fujimoto, James G.

2017-01-01

Up to 40% of patients undergoing breast conserving surgery for breast cancer require repeat surgeries due to close to or positive margins. The lengthy processing required for evaluating surgical margins by standard paraffin embedded histology precludes its use during surgery and therefore, technologies for rapid evaluation of surgical pathology could improve the treatment of breast cancer by reducing the number of surgeries required. We demonstrate real-time histological evaluation of breast cancer surgical specimens by staining specimens with acridine orange (AO) and sulforhodamine 101 (SR101) analogously to hematoxylin and eosin (H&E) and then imaging the specimens with fluorescence nonlinear microscopy (NLM) using a compact femtosecond fiber laser. A video-rate computational light absorption model was used to produce realistic virtual H&E images of tissue in real time and in three dimensions. NLM imaging could be performed to depths of 100 µm below the tissue surface, which is important since many surgical specimens require subsurface evaluation due to artifacts on the tissue surface from electrocautery, surgical ink or debris from specimen handling. We validate this method by expert review of NLM images compared to formalin fixed, paraffin embedded (FFPE) H&E histology. Diagnostically important features such as normal terminal ductal lobular units, fibrous and adipose stromal parenchyma, inflammation, invasive carcinoma, and in-situ lobular and ductal carcinoma were present in NLM images associated with pathologies identified on standard FFPE H&E histology. We demonstrate that AO and SR101 were extracted to undetectable levels after FFPE processing and fluorescence in situ hybridization (FISH) HER2 amplification status was unaffected by the NLM imaging protocol. This method potentially enables cost-effective, real-time histological guidance of surgical resections. PMID:29131161

Facilitating Identification of Poorly Preserved Marine Microfossils through 3D Printing

NASA Astrophysics Data System (ADS)

Christensen, R. V.; Robinson, M. M.; Sessa, J.

2016-12-01

The Paleocene-Eocene Thermal Maximum (PETM) was a period of sudden and intense global warming that occurred 56 Myr, and is widely considered a possible analogue for future climatic changes. Marine microfossils are important proxies used in the reconstruction of PETM paleoenvironments and paleoclimate. The correct species-level identification of foraminifera and pteropod specimens is necessary to understand ocean temperature, chemistry, nutrient availability, and ecosystem structure during this hyperthermal event. During periods of extreme or rapid environmental perturbations foraminifera can be poorly preserved. Pteropod identification is equally challenging as aragonitic shells are vulnerable to changing ocean acidity and often only internal molds are left to be identified. The macroscopic rendering of the internal and external test morphology of marine microfossils via 3D printing allows for a more experiential species-recognition education, especially of difficult to identify specimens. A selected microfossil specimen is scanned using computerized tomography (CT), creating x-ray slices of the specimen that are then processed into a digital model. The digitized fossil can then be analyzed using 3D software and subsequently printed using a wide variety of materials. The magnified model can be easily manipulated in a student's hand, and thus can be studied in a more visible and tactile way than traditional methods allow. This invaluable teaching tool physically manifests what was previously limited to textbook images and illustrations or the view field of a microscope. We show the step-by-step 3-D printing process of several PETM marine microfossil specimens from CT scans and demonstrate their advantage over 2-D SEM images for learning to identify microfossils to the species level. In addition, we provide samples to demonstrate the utility of 3-D models in identifying poorly preserved foraminifer specimens and species of pteropods from internal molds.

Residual stress and crack initiation in laser clad composite layer with Co-based alloy and WC + NiCr

NASA Astrophysics Data System (ADS)

Lee, Changmin; Park, Hyungkwon; Yoo, Jaehong; Lee, Changhee; Woo, WanChuck; Park, Sunhong

2015-08-01

Although laser cladding process has been widely used to improve the wear and corrosion resistance, there are unwanted cracking issues during and/or after laser cladding. This study investigates the tendency of Co-based WC + NiCr composite layers to cracking during the laser cladding process. Residual stress distributions of the specimen are measured using neutron diffraction and elucidate the correlation between the residual stress and the cracking in three types of cylindrical specimens; (i) no cladding substrate only, (ii) cladding with 100% stellite#6, and (iii) cladding with 55% stellite#6 and 45% technolase40s. The microstructure of the clad layer was composed of Co-based dendrite and brittle eutectic phases at the dendritic boundaries. And WC particles were distributed on the matrix forming intermediate composition region by partial melting of the surface of particles. The overlaid specimen exhibited tensile residual stress, which was accumulated through the beads due to contraction of the coating layer generated by rapid solidification, while the non-clad specimen showed compressive. Also, the specimen overlaid with 55 wt% stellite#6 and 45 wt% technolase40s showed a tensile stress higher than the specimen overlaid with 100% stellite#6 possibly, due to the difference between thermal expansion coefficients of the matrix and WC particles. Such tensile stresses can be potential driving force to provide an easy crack path ways for large brittle fractures combined with the crack initiation sites such as the fractured WC particles, pores and solidification cracks. WC particles directly caused clad cracks by particle fracture under the tensile stress. The pores and solidification cracks also affected as initiation sites and provided an easy crack path ways for large brittle fractures.

Noncontact Measurement Of Sizes And Eccentricities Of Holes

NASA Technical Reports Server (NTRS)

Chern, Engmin J.

1993-01-01

Semiautomatic eddy-current-probe apparatus makes noncontact measurements of nominally round holes in electrically conductive specimens and processes measurement data into diameters and eccentricities of holes. Includes x-y translation platform, which holds specimen and moves it horizontally. Probe mounted on probe scanner, positioning probe along vertical (z) direction and rotates probe about vertical axis at preset low speed. Eddy-current sensing coil mounted in side of probe near tip. As probe rotates, impedance analyzer measures electrical impedance (Z) of coil as function of instantaneous rotation angle. Translation and rotation mechanisms and impedance analyzer controlled by computer, which also processes impedance-measurement data.

Immunocytochemical detection of astrocytes in brain slices in combination with Nissl staining.

PubMed

Korzhevskii, D E; Otellin, V A

2005-07-01

The present study was performed to develop a simple and reliable method for the combined staining of specimens to allow the advantages of immunocytochemical detection of astrocytes and assessment of the functional state of neurons by the Nissl method to be assessed simultaneously. The protocol suggested for processing paraffin sections allows preservation of tissue structure at high quality and allows the selective identification of astrocytes with counterstaining of neurons by the Nissl method. The protocol can be used without modification for processing brain specimens from humans and various mammals--except mice and rabbits.

In situ TEM and synchrotron characterization of U–10Mo thin specimen annealed at the fast reactor temperature regime

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yun, Di, E-mail: diyun1979@xjtu.edu.cn; Xi'an Jiao Tong University, 28 Xian Ning West Road, Xi'an 710049; Mo, Kun

2015-12-15

U–Mo metallic alloys have been extensively used for the Reduced Enrichment for Research and Test Reactors (RERTR) program, which is now known as the Office of Material Management and Minimization under the Conversion Program. This fuel form has also recently been proposed as fast reactor metallic fuels in the recent DOE Ultra-high Burnup Fast Reactor project. In order to better understand the behavior of U–10Mo fuels within the fast reactor temperature regime, a series of annealing and characterization experiments have been performed. Annealing experiments were performed in situ at the Intermediate Voltage Electron Microscope (IVEM-Tandem) facility at Argonne National Laboratorymore » (ANL). An electro-polished U–10Mo alloy fuel specimen was annealed in situ up to 700 °C. At an elevated temperature of about 540 °C, the U–10Mo specimen underwent a relatively slow microstructure transition. Nano-sized grains were observed to emerge near the surface. At the end temperature of 700 °C, the near-surface microstructure had evolved to a nano-crystalline state. In order to clarify the nature of the observed microstructure, Laue diffraction and powder diffraction experiments were carried out at beam line 34-ID of the Advanced Photon Source (APS) at ANL. Phases present in the as-annealed specimen were identified with both Laue diffraction and powder diffraction techniques. The U–10Mo was found to recrystallize due to thermally-induced recrystallization driven by a high density of pre-existing dislocations. A separate in situ annealing experiment was carried out with a Focused Ion Beam processed (FIB) specimen. A similar microstructure transition occurred at a lower temperature of about 460 °C with a much faster transition rate compared to the electro-polished specimen. - Highlights: • TEM annealing experiments were performed in situ at the IVEM facility up to fast reactor temperature. • At 540 °C, the U-10Mo specimen underwent a slow microstructure transition where nano-sized grains were observed to emerge. • UO{sub 2} phase exists at the thin area of the as-annealed specimen whereas U-10Mo γ phase dominated at the thicker part. • Bcc γ U-10Mo recrystallized to become nano-meter sized crystallites near the specimen surface. • A separateannealing experiment was conducted with a FIB processed specimen where similar transition occurred at a lower temperature of 460 °C with a faster rate.« less

Iterative expansion microscopy

PubMed Central

Chang, Jae-Byum; Chen, Fei; Yoon, Young-Gyu; Jung, Erica E.; Babcock, Hazen; Kang, Jeong Seuk; Asano, Shoh; Suk, Ho-Jun; Pak, Nikita; Tillberg, Paul W.; Wassie, Asmamaw; Cai, Dawen; Boyden, Edward S.

2017-01-01

We recently discovered it was possible to physically magnify preserved biological specimens by embedding them in a densely crosslinked polyelectrolyte gel, anchoring key labels or biomolecules to the gel, mechanically homogenizing the specimen, and then swelling the gel-specimen composite by ~4.5x in linear dimension, a process we call expansion microscopy (ExM). Here we describe iterative expansion microscopy (iExM), in which a sample is expanded, then a second swellable polymer mesh is formed in the space newly opened up by the first expansion, and finally the sample is expanded again. iExM expands biological specimens ~4.5 × 4.5 or ~20x, and enables ~25 nm resolution imaging of cells and tissues on conventional microscopes. We used iExM to visualize synaptic proteins, as well as the detailed architecture of dendritic spines, in mouse brain circuitry. PMID:28417997

Strain-Annealing Based Grain Boundary Engineering to Evaluate its Sole Implication on Intergranular Corrosion in Extra-Low Carbon Type 304L Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Pradhan, S. K.; Bhuyan, P.; Kaithwas, C.; Mandal, Sumantra

2018-05-01

Strain-annealing based thermo-mechanical processing has been performed to promote grain boundary engineering (GBE) in an extra-low carbon type austenitic stainless steel without altering the grain size and residual strain to evaluate its sole influence on intergranular corrosion. Single-step processing comprising low pre-strain ( 5 and 10 pct) followed by annealing at 1273 K for 1 hour have resulted in a large fraction of Σ3 n boundaries and significant disruption in random high-angle grain boundaries (RHAGBs) connectivity. This is due to the occurrence of prolific multiple twinning in these specimens as confirmed by their large twin-related domain and twin-related grain size ratio. Among the iterative processing, the schedule comprising two cycles of 10 and 5 pct deformation followed by annealing at 1173 K for 1 hour has yielded the optimum GBE microstructure with the grain size and residual strain akin to the as-received condition. The specimens subjected to the higher number of iterations failed to realize GBE microstructures due to the occurrence of partial recrystallization. Owing to the optimum grain boundary character distribution, the GBE specimen has exhibited remarkable resistance against sensitization and intergranular corrosion as compared to the as-received condition. Furthermore, the lower depth of percolation in the GBE specimen is due to the significant disruption of RHAGBs connectivity as confirmed from its large twin-related domain and lower fractal dimension.

Strain-Annealing Based Grain Boundary Engineering to Evaluate its Sole Implication on Intergranular Corrosion in Extra-Low Carbon Type 304L Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Pradhan, S. K.; Bhuyan, P.; Kaithwas, C.; Mandal, Sumantra

2018-07-01

Strain-annealing based thermo-mechanical processing has been performed to promote grain boundary engineering (GBE) in an extra-low carbon type austenitic stainless steel without altering the grain size and residual strain to evaluate its sole influence on intergranular corrosion. Single-step processing comprising low pre-strain ( 5 and 10 pct) followed by annealing at 1273 K for 1 hour have resulted in a large fraction of Σ3 n boundaries and significant disruption in random high-angle grain boundaries (RHAGBs) connectivity. This is due to the occurrence of prolific multiple twinning in these specimens as confirmed by their large twin-related domain and twin-related grain size ratio. Among the iterative processing, the schedule comprising two cycles of 10 and 5 pct deformation followed by annealing at 1173 K for 1 hour has yielded the optimum GBE microstructure with the grain size and residual strain akin to the as-received condition. The specimens subjected to the higher number of iterations failed to realize GBE microstructures due to the occurrence of partial recrystallization. Owing to the optimum grain boundary character distribution, the GBE specimen has exhibited remarkable resistance against sensitization and intergranular corrosion as compared to the as-received condition. Furthermore, the lower depth of percolation in the GBE specimen is due to the significant disruption of RHAGBs connectivity as confirmed from its large twin-related domain and lower fractal dimension.

Retrospective study of urinalysis for dl-amphetamine and dl-methamphetamine analysis under current Department of Defense guidelines.

PubMed

Shippee, R L; Kippenberger, D J

2000-09-01

Under current Department of Defense (DOD) directive, the laboratories certified to conduct urinalyis testing in support of the DOD Drug Deterrence Program are required to conduct dl-isomer analysis on all specimens that confirm at a concentration greater than 500 ng/mL methamphetamine (METH). Although the same cutoff concentration is required for amphetamine (AMP) reporting, there is no requirement for dl-isomer analysis of AMP-positive specimens. Of the 894,823 specimens screened by the Army Drug Testing Laboratory at Ft. Meade, MD during a 19-month period, 339 confirmed positive for METH. From this positive population, seven specimens failed to confirm at or above the DOD cutoff of > 20% d-isomer. One of the seven specimens contained 534 ng/mL l-AMP and was reported positive for AMP. Although 100% of the AMP was the l-isomer, under current DOD directive, this information was not passed along to the Medical Review Officers (MRO) to assist them during the interview process. Although this situation appears to be a rare event, consideration should be given to requiring dl-isomer analysis of AMP-positive specimens and forwarding this information to the MRO.

Fatigue Behavior of Porous Ti-6Al-4V Made by Laser-Engineered Net Shaping.

PubMed

Razavi, Seyed Mohammad Javad; Bordonaro, Giancarlo G; Ferro, Paolo; Torgersen, Jan; Berto, Filippo

2018-02-12

The fatigue behavior and fracture mechanisms of additively manufactured Ti-6Al-4V specimens are investigated in this study. Three sets of testing samples were fabricated for the assessment of fatigue life. The first batch of samples was built by using Laser-Engineered Net Shaping (LENS) technology, a Direct Energy Deposition (DED) method. Internal voids and defects were induced in a second batch of samples by changing LENS machine processing parameters. Fatigue performance of these samples is compared to the wrought Ti-6Al-4V samples. The effects of machine-induced porosity are assessed on mechanical properties and results are presented in the form of SN curves for the three sets of samples. Fracture mechanisms are examined by using Scanning Electron Microscopy (SEM) to characterize the morphological characteristics of the failure surface. Different fracture surface morphologies are observed for porous and non-porous specimens due to the combination of head write speed and laser power. Formation of defects such as pores, unmelted regions, and gas entrapments affect the failure mechanisms in porous specimens. Non-porous specimens exhibit fatigue properties comparable with that of the wrought specimens, but porous specimens are found to show a tremendous reduced fatigue strength.

Process and apparatus for analyzing specimens for the presence of microorganisms therein

NASA Technical Reports Server (NTRS)

Vannest, Richard D. (Inventor); Meyer, Michael C. (Inventor); Gibson, Sandra F. (Inventor); Keyser, George F. (Inventor); Jones, Paul W. (Inventor); Aldridge, Jr., Clifton (Inventor); Holen, James T. (Inventor)

1980-01-01

Microorganisms in a specimen are detected, identified, and enumerated by introducing the specimen into a sampling cartridge and diluting the specimen with a known volume of water within the cartridge. The cartridge has a manifold and several cassettes attached to the manifold. Each cassette contains a serpentine flow channel having a series of filters therein and a detection cell located downstream from each filter. The flow channel in each cassette also contains a culture medium which is freeze dried and is highly selective in the sense that it promotes the growth of one type of microorganism, but not others. The mixture of the specimen and water flows from the manifold into the flow channel of each cassette where it rehydrates the culture medium therein and further flows through the filters. Each filter removes a known proportion of the microorganisms from the mixture of specimen, water and medium, thereby effecting a serial dilution. After the cassettes are heated to incubate the microoganisms, the detection cells are observed for growth of the microorganisms therein which is manifested in a change in the light transmitting characteristics of the mixtures within the cells.

An Experimental Study of the Fracture Coalescence Behaviour of Brittle Sandstone Specimens Containing Three Fissures

NASA Astrophysics Data System (ADS)

Yang, S. Q.; Yang, D. S.; Jing, H. W.; Li, Y. H.; Wang, S. Y.

2012-07-01

To analyse the fracture coalescence behaviour of rock, rectangular prismatic sandstone specimens (80 × 160 × 30 mm in size) containing three fissures were tested under uniaxial compression. The strength and deformation behaviours of the specimens are first analysed by investigating the effects of the ligament angle β2 on the peak strength, peak strain and crack initiation stress of the specimens. To confirm the sequence of crack coalescence, a photographic monitoring technique is used throughout the entire period of deformation. Based on the results, the relationship between the real-time crack coalescence process and the axial stress-strain curve of brittle sandstone specimens is also developed, and this relationship can be used to evaluate the macroscopic deformation characteristics of pre-cracked rock. The equivalent strain evolution fields of the specimen, with α = β1 = 45° and β2 = 90°, are obtained using the digital image correlation technique and show good agreement with the experimental results of pre-cracked brittle sandstone. These experimental results are expected to improve the understanding of fracture mechanisms and be used in rock engineering with intermittent structures, such as deep underground excavated tunnels.

49 CFR 40.193 - What happens when an employee does not provide a sufficient amount of urine for a drug test?

Code of Federal Regulations, 2010 CFR

2010-10-01

...) If the employee refuses to make the attempt to provide a new urine specimen or leaves the collection site before the collection process is complete, you must discontinue the collection, note the fact on... attempt to provide the specimen, you must discontinue the collection, note the fact on the “Remarks” line...

The Manufacturing of High Porosity Iron with an Ultra-Fine Microstructure via Free Pressureless Spark Plasma Sintering

PubMed Central

Cui, Guodong; Wei, Xialu; Olevsky, Eugene A.; German, Randall M.; Chen, Junying

2016-01-01

High porosity (>40 vol %) iron specimens with micro- and nanoscale isotropic pores were fabricated by carrying out free pressureless spark plasma sintering (FPSPS) of submicron hollow Fe–N powders at 750 °C. Ultra-fine porous microstructures are obtained by imposing high heating rates during the preparation process. This specially designed approach not only avoids the extra procedures of adding and removing space holders during the formation of porous structures, but also triggers the continued phase transitions of the Fe–N system at relatively lower processing temperatures. The compressive strength and energy absorption characteristics of the FPSPS processed specimens are examined here to be correspondingly improved as a result of the refined microstructure. PMID:28773617

Eddy current characterization of magnetic treatment of nickel 200

NASA Technical Reports Server (NTRS)

Chern, E. J.

1993-01-01

Eddy current methods have been applied to characterize the effect of magnetic treatments on component service-life extension. Coil impedance measurements were acquired and analyzed on nickel 200 specimens that have been subjected to many mechanical and magnetic engineering processes: annealing, applied strain, magnetic field, shot peening, and magnetic field after peening. Experimental results have demonstrated a functional relationship between coil impedance, resistance and reactance, and specimens subjected to various engineering processes. It has shown that magnetic treatment does induce changes in electromagnetic properties of nickel 200 that then exhibit evidence of stress relief. However, further fundamental studies are necessary for a thorough understanding of the exact mechanism of the magnetic field processing effect on machine-tool service life.

Eddy current characterization of magnetic treatment of materials

NASA Technical Reports Server (NTRS)

Chern, E. James

1992-01-01

Eddy current impedance measuring methods have been applied to study the effect that magnetically treated materials have on service life extension. Eddy current impedance measurements have been performed on Nickel 200 specimens that have been subjected to many mechanical and magnetic engineering processes: annealing, applied strain, magnetic field, shot peening, and magnetic field after peening. Experimental results have demonstrated a functional relationship between coil impedance, resistance and reactance, and specimens subjected to various engineering processes. It has shown that magnetic treatment does induce changes in a material's electromagnetic properties and does exhibit evidence of stress relief. However, further fundamental studies are necessary for a thorough understanding of the exact mechanism of the magnetic-field processing effect on machine tool service life.

In situ high-energy X-ray diffraction study of tensile deformation of neutron-irradiated polycrystalline Fe-9%Cr alloy

DOE PAGES

Zhang, Xuan; Li, Meimei; Park, Jun -Sang; ...

2016-12-30

The effect of neutron irradiation on tensile deformation of a Fe-9wt.%Cr alloy was investigated using in situ high-energy synchrotron X-ray diffraction during room-temperature uniaxial tensile tests. New insights into the deformation mechanisms were obtained through the measurements of lattice strain evolution and the analysis of diffraction peak broadening using the modified Williamson-Hall method. Two neutron-irradiated specimens, one irradiated at 300 °C to 0.01 dpa and the other at 450 °C to 0.01dpa, were tested along with an unirradiated specimen. The macroscopic stress–strain curves of the irradiated specimens showed increased strength, reduced ductility and work-hardening exponent compared to the unirradiated specimen.more » The evolutions of the lattice strain, the dislocation density and the coherent scattering domain size in the deformation process revealed different roles of the submicroscopic defects in the 300°C/0.01 dpa specimen and the TEM-visible nanometer-sized dislocation loops in the 450°C/0.01 dpa specimen: submicroscopic defects extended the linear work hardening stage (stage II) to a higher strain, while irradiation-induced dislocation loops were more effective in dislocation pinning. Lastly, while the work hardening rate of stage II was unaffected by irradiation, significant dynamic recovery in stage III in the irradiated specimens led to the early onset of necking without stage IV as observed in the unirradiated specimen.« less

Full Field Deformation Measurements in Tensile Kolsky Bar Experiments: Studies and Detailed Analysis of the Early Time History

NASA Astrophysics Data System (ADS)

Sutton, M. A.; Gilat, A.; Seidt, J.; Rajan, S.; Kidane, A.

2018-01-01

The very early stages of high rate tensile loading are important when attempting to characterize the response of materials during the transient loading time. To improve understanding of the conditions imposed on the specimen during the transient stage, a series of high rate loading experiments are performed using a Kolsky tensile bar system. Specimen forces and velocities during the high rate loading experiment are obtained by performing a thorough method of characteristics analysis of the system employed in the experiments. The in-situ full-field specimen displacements, velocities and accelerations during the loading process are quantified using modern ultra-high-speed imaging systems to provide detailed measurements of specimen response, with emphasis on the earliest stages of loading. Detailed analysis of the image-based measurements confirms that conditions are nominally consistent with those necessary for use of the one-dimensional wave equation within the relatively thin, dog-bone shaped tensile specimen. Specifically, measurements and use of the one-dimensional wave equation show clearly that the specimen has low inertial stresses in comparison to the applied transmitted force. Though the accelerations of the specimen continue for up to 50 μs, measurements show that the specimen is essentially in force equilibrium beginning a few microseconds after initial loading. These local measurements contrast with predictions based on comparison of the wave-based incident force measurements, which suggest that equilibrium occurs much later, on the order of 40-50 μs .

Specimens with an Artifact Appearing as 'Three Spines' in Milnesium tardigradum var. trispinosa Rahm, 1931 (Tardigrada).

PubMed

Suzuki, Atsushi C

2016-08-01

Milnesium tardigradum trispinosa Rahm, 1931 is characterized by its three spines at the posterior end of the animal, but has never been reported since its original description. Among mounted specimens of Milnesium sp. from Japan and M. tardigradum s. s. from France, several cases with these 'three spines' were observed. In these samples, the character was formed by an artifact of the fixation process. Images of these specimens show such a striking similarity to Milnesium tardigradum trispinosa that this taxon must be considered as having been erroneously established as a result of misinterpretation of an artifact and no longer valid.

Ultrasonic scanning system for imaging flaw growth in composites

NASA Technical Reports Server (NTRS)

Kiraly, L. J.; Meyn, E. H.

1982-01-01

A system for measuring and visually representing damage in composite specimens while they are being loaded was demonstrated. It uses a hobbiest grade microcomputer system to control data taking and image processing. The system scans operator selected regions of the specimen while it is under load in a tensile test machine and measures internal damage by the attenuation of a 2.5 MHz ultrasonic beam passed through the specimen. The microcomputer dynamically controls the position of ultrasonic transducers mounted on a two axis motor driven carriage. As many as 65,536 samples can be taken and filed on a floppy disk system in less than four minutes.

Development of Statistical Process Control Methodology for an Environmentally Compliant Surface Cleaning Process in a Bonding Laboratory

NASA Technical Reports Server (NTRS)

Hutchens, Dale E.; Doan, Patrick A.; Boothe, Richard E.

1997-01-01

Bonding labs at both MSFC and the northern Utah production plant prepare bond test specimens which simulate or witness the production of NASA's Reusable Solid Rocket Motor (RSRM). The current process for preparing the bonding surfaces employs 1,1,1-trichloroethane vapor degreasing, which simulates the current RSRM process. Government regulations (e.g., the 1990 Amendments to the Clean Air Act) have mandated a production phase-out of a number of ozone depleting compounds (ODC) including 1,1,1-trichloroethane. In order to comply with these regulations, the RSRM Program is qualifying a spray-in-air (SIA) precision cleaning process using Brulin 1990, an aqueous blend of surfactants. Accordingly, surface preparation prior to bonding process simulation test specimens must reflect the new production cleaning process. The Bonding Lab Statistical Process Control (SPC) program monitors the progress of the lab and its capabilities, as well as certifies the bonding technicians, by periodically preparing D6AC steel tensile adhesion panels with EA-91 3NA epoxy adhesive using a standardized process. SPC methods are then used to ensure the process is statistically in control, thus producing reliable data for bonding studies, and identify any problems which might develop. Since the specimen cleaning process is being changed, new SPC limits must be established. This report summarizes side-by-side testing of D6AC steel tensile adhesion witness panels and tapered double cantilevered beams (TDCBs) using both the current baseline vapor degreasing process and a lab-scale spray-in-air process. A Proceco 26 inches Typhoon dishwasher cleaned both tensile adhesion witness panels and TDCBs in a process which simulates the new production process. The tests were performed six times during 1995, subsequent statistical analysis of the data established new upper control limits (UCL) and lower control limits (LCL). The data also demonstrated that the new process was equivalent to the vapor degreasing process.

Residual Ductility and Microstructural Evolution in Continuous-Bending-under-Tension of AA-6022-T4

PubMed Central

Zecevic, Milovan; Roemer, Timothy J.; Knezevic, Marko; Korkolis, Yannis P.; Kinsey, Brad L.

2016-01-01

A ubiquitous experiment to characterize the formability of sheet metal is the simple tension test. Past research has shown that if the material is repeatedly bent and unbent during this test (i.e., Continuous-Bending-under-Tension, CBT), the percent elongation at failure can significantly increase. In this paper, this phenomenon is evaluated in detail for AA-6022-T4 sheets using a custom-built CBT device. In particular, the residual ductility of specimens that are subjected to CBT processing is investigated. This is achieved by subjecting a specimen to CBT processing and then creating subsize tensile test and microstructural samples from the specimens after varying numbers of CBT cycles. Interestingly, the engineering stress initially increases after CBT processing to a certain number of cycles, but then decreases with less elongation achieved for increasing numbers of CBT cycles. Additionally, a detailed microstructure and texture characterization are performed using standard scanning electron microscopy and electron backscattered diffraction imaging. The results show that the material under CBT preserves high integrity to large plastic strains due to a uniform distribution of damage formation and evolution in the material. The ability to delay ductile fracture during the CBT process to large plastic strains, results in formation of a strong <111> fiber texture throughout the material. PMID:28773257

Ultrasonic probing of the fracture process zone in rock using surface waves

NASA Technical Reports Server (NTRS)

Swanson, P. L.; Spetzler, H.

1984-01-01

A microcrack process zone is frequently suggested to accompany macrofractures in rock and play an important role in the resistance to fracture propagation. Attenuation of surface waves propagating through mode I fractures in wedge-loaded double-cantilever beam specimens of Westerly granite has been recorded in an attempt to characterize the structure of the fracture process zone. The ultrasonic measurements do not support the generally accepted model of a macroscopic fracture that incrementally propagates with the accompaniment of a cloud of microcracks. Instead, fractures in Westerly granite appear to form as gradually separating surfaces within a zone having a width of a few millimeters and a length of several tens of millimeters. A fracture process zone of this size would necessitate the use of meter-sized specimens in order for linear elastic fracture mechanics to be applicable.

Identification of Mycobacterium tuberculosis and rifampin resistance in clinical specimens using the Xpert MTB/RIF assay.

PubMed

Kim, Cheol-Hong; Hyun, In Gyu; Hwang, Yong Il; Kim, Dong-Gyu; Lee, Chang Youl; Lee, Myung Goo; Jung, Ki-Suck; Woo, Heungjeong; Hyun, Jeongwon; Kim, Hyun Soo; Park, Myung Jae

2015-01-01

The Xpert MTB/RIF assay is a novel real-time polymerase chain reaction technique for the detection of the Mycobacterium tuberculosis (MTB) complex and rifampin (RIF) resistance. We evaluated the performance of this assay in identifying MTB and resistance to RIF in clinical specimens. We analyzed clinical specimens from 383 patients with suspected TB who were hospitalized at a secondary hospital in Korea. Specimens were processed using the Xpert MTB/RIF assay, acid-fast bacilli smear and culture, and drug susceptibility test (DST). Among the 444 clinical samples analyzed, the Xpert MTB/RIF assay identified MTB in 56 (13.8%) of 405 respiratory specimens, but did not detect MTB in the remaining 39 non-respiratory specimens. Of the 65 pulmonary TB patients, 52 (80.0%) were confirmed by using mycobacterial culture as a reference standard. The sensitivity, specificity, PPV, and NPV of the Xpert MTB/RIF assay were 73.85%, 99.03%, 94.12%, and 94.72%, respectively. Among five patients with RIF resistance determined by the Xpert MTB/RIF assay, four (80%) were confirmed as suffering from multidrug-resistant (MDR) TB by DST. The Xpert MTB/RIF assay appears to be an accurate, simple, and useful technique for detecting MTB, especially in respiratory specimens. However, RIF resistance, if detected, should be verified with DST. © 2015 by the Association of Clinical Scientists, Inc.

In-line assay monitor for uranium hexafluoride

DOEpatents

Wallace, Steven A.

1981-01-01

An in-line assay monitor for determining the content of uranium-235 in a uranium hexafluoride gas isotopic separation system is provided which removes the necessity of complete access to the operating parameters of the system for determining the uranium-235 content. The monitor is intended for uses such as safeguard applications to assure that weapons grade uranium is not being produced in an enrichment cascade. The method and monitor for carrying out the method involve cooling of a radiation pervious chamber connected in fluid communication with the selected point in the system to withdraw a specimen and solidify the specimen in the chamber. The specimen is irradiated by means of an ionizing radiation source of energy different from that of the 185 keV gamma emissions from the uranium-235 present in the specimen. Simultaneously, the gamma emissions from the uranium-235 of the specimen and the source emissions transmitted through the sample are counted and stored in a multiple channel analyzer. The uranium-235 content of the specimen is determined from the comparison of the accumulated 185 keV energy counts and the reference energy counts. The latter is used to measure the total uranium isotopic content of the specimen. The process eliminates the necessity of knowing the system operating conditions and yet obtains the necessary data without need for large scintillation crystals and sophisticated mechanical designs.

Experimental study on lateral strength of wall-slab joint subjected to lateral cyclic load

NASA Astrophysics Data System (ADS)

Masrom, Mohd Asha'ari; Mohamad, Mohd Elfie; Hamid, Nor Hayati Abdul; Yusuff, Amer

2017-10-01

Tunnel form building has been utilised in building construction since 1960 in Malaysia. This method of construction has been applied extensively in the construction of high rise residential house (multistory building) such as condominium and apartment. Most of the tunnel form buildings have been designed according to British standard (BS) whereby there is no provision for seismic loading. The high-rise tunnel form buildings are vulnerable to seismic loading. The connections between slab and shear walls in the tunnel-form building constitute an essential link in the lateral load resisting mechanism. Malaysia is undergoing a shifting process from BS code to Eurocode (EC) for building construction since the country has realised the safety threats of earthquake. Hence, this study is intended to compare the performance of the interior wall slab joint for a tunnel form structure designed based on Euro and British codes. The experiment included a full scale test of the wall slab joint sub-assemblages under reversible lateral cyclic loading. Two sub-assemblage specimens of the wall slab joint were designed and constructed based on both codes. Each specimen was tested using lateral displacement control (drift control). The specimen designed by using Eurocode was found could survive up to 3.0% drift while BS specimen could last to 1.5% drift. The analysis results indicated that the BS specimen was governed by brittle failure modes with Ductility Class Low (DCL) while the EC specimen behaved in a ductile manner with Ductility Class Medium (DCM). The low ductility recorded in BS specimen was resulted from insufficient reinforcement provided in the BS code specimen. Consequently, the BS specimen could not absorb energy efficiently (low energy dissipation) and further sustain under inelastic deformation.

Histological analysis of the biocompatibility of calcium hydroxide associated with a new vehicle.

PubMed

Simi Junior, Jacy; Machado, Ricardo; Souza, Cássio José Alves de; Loyola, Adriano Motta; Vansan, Luiz Pascoal; Antoniazzi, João Humberto

2015-01-01

Several substances have been researched to act as vehicles associated with calcium hydroxide. The specific type of vehicle is directly related to the effectiveness of the ionic dissociation, antimicrobial action, and biocompatibility of this medication. To make a histological evaluation of the biocompatibility of calcium hydroxide associated with a new vehicle (triethanolamine), compared with polyethylene glycol, saline solution, and olive oil. Fifty mice of guinea pig species were randomly divided into five groups (n = 10) according to each vehicle used--Group 1: calcium hydroxide, Group 2: triethanolamine, Group 3: polyethylene glycol, Group 4: saline solution, and Group 5: olive oil--and further divided into subgroups according to the two analysis periods--(a) 30 and (b) 90 days. Teflon carriers filled with the evaluated substances were placed in standardized bone cavities in the anterior mandible region. The animals were euthanized to perform a histological analysis after the time periods analyzed. In 30 days, specimens from Groups 1, 3, and 5 showed a very pronounced inflammatory response. Specimens from Group 2 showed an inflammatory reaction ranging from mild to severe, with rapid resorption of the material and progressive advancement of osteoid tissue into the teflon carriers. Specimens from Group 4 showed a moderate inflammatory reaction. In 90 days, specimens from Group 1 showed a very pronounced fibrous replacement. In regard to Group 2 specimens, the tested material was solubilized and replaced by newly formed bone tissue. For Groups 3 and 5 specimens, the inflammatory reaction went from acute to moderate. In relation to Group 4 specimens, an organized bone formation process was observed. Specimens from Group 2 showed higher biocompatibility, especially as compared with the specimens from Groups 3 and 5.

49 CFR 40.153 - How does the MRO notify employees of their right to a test of the split specimen?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false How does the MRO notify employees of their right to a test of the split specimen? 40.153 Section 40.153 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Medical Review Officers and the Verification Process § 40.153 Ho...

Infrared Pyrometry From Room Temperature To 700 Degrees C

NASA Technical Reports Server (NTRS)

Wheeler, Donald R.; Jones, William R., Jr.; Pepper, Stephen V.

1989-01-01

Consistent readings obtained when specimens prepared appropriately. New method largely overcomes limitations. Transmission of infrared increased by replacing customary metal-coated glass viewing port with quartz viewing port covered with tantalum mesh. Commercially available infrared microscope with focal distance of 53 cm focuses on spot only 1 mm wide on specimen. Microscope operated as radiometer. Output of detector varies by several orders of magnitude, processed by logarithmic amplifier before reading.

Magneto-Elastic behaviour of Steels for Naval Applications

DTIC Science & Technology

1991-02-01

test specimens to be inserted. The specimens are preferably long and thin to avoid demagnetization effects, but are also preferably short and squat ...jr.".-.IC’’" ?!o w:.I ,,od ntt’pcrtJ B15 q12 fA-l spc +icob are as ’l . The stress level was -200l MIa for the Dt l((Td) ’ process, and ranged from 0

Characterization of material parameters for high speed forming and cutting via experiment and inverse simulation

NASA Astrophysics Data System (ADS)

Scheffler, Christian; Psyk, Verena; Linnemann, Maik; Tulke, Marc; Brosius, Alexander; Landgrebe, Dirk

2018-05-01

High speed velocity effects in production technology provide a broad range of technological and economic advantages [1, 2]. However, exploiting them necessitates the knowledge of strain rate dependent material behavior in process modelling. In general, high speed material data characterization features several difficulties and requires sophisticated approaches in order to provide reliable material data. This paper proposes two innovative concepts with electromagnetic and pneumatic drive and an approach for material characterization in terms of strain rate dependent flow curves and parameters of failure or damage models. The test setups have been designed for investigations of strain rates up to 105 s-1. In principle, knowledge about the temporary courses and local distributions of stress and strain in the specimen is essential for identifying material characteristics, but short process times, fast changes of the measurement values, small specimen size and frequently limited accessibility of the specimen during the test hinder directly measuring these parameters at high-velocity testing. Therefore, auxiliary test parameters, which are easier to measure, are recorded and used as input data for an inverse numerical simulation that provides the desired material characteristics, e.g. the Johnson-Cook parameters, as a result. These parameters are a force equivalent strain signal on a measurement body and the displacement of the upper specimen edge.

Design and evaluation of a foam-filled hat-stiffened panel concept for aircraft primary structural applications

NASA Technical Reports Server (NTRS)

Ambur, Damodar R.

1993-01-01

Geodesically stiffened structures are very efficient in carrying combined bending, torsion, and pressure loading that is typical of primary aircraft structures. They are also very damage tolerant since there are multiple load paths available to redistribute loads compared to prismatically stiffened structures. Geodesically stiffened structures utilize continuous filament composite materials which make them amenable to automated manufacturing processes to reduce cost. The current practice for geodesically stiffened structures is to use a solid blade construction for the stiffener. This stiffener configuration is not an efficient concept and there is a need to identify other stiffener configurations that are more efficient but utilize the same manufacturing process as the solid blade. This paper describes a foam-filled stiffener cross section that is more efficient than a solid-blade stiffener in the load range corresponding to primary aircraft structures. A prismatic hat-stiffener panel design is then selected for structural evaluation in uni-axial compression with and without impact damage. Experimental results for both single stiffener specimens and multi-stiffener panel specimens are presented. Finite element analysis results are presented that predict the buckling and postbuckling response of the test specimens. Analytical results for both the element and panel specimens are compared with experimental results.

Dimensional changes of acrylic resin denture bases: conventional versus injection-molding technique.

PubMed

Gharechahi, Jafar; Asadzadeh, Nafiseh; Shahabian, Foad; Gharechahi, Maryam

2014-07-01

Acrylic resin denture bases undergo dimensional changes during polymerization. Injection molding techniques are reported to reduce these changes and thereby improve physical properties of denture bases. The aim of this study was to compare dimensional changes of specimens processed by conventional and injection-molding techniques. SR-Ivocap Triplex Hot resin was used for conventional pressure-packed and SR-Ivocap High Impact was used for injection-molding techniques. After processing, all the specimens were stored in distilled water at room temperature until measured. For dimensional accuracy evaluation, measurements were recorded at 24-hour, 48-hour and 12-day intervals using a digital caliper with an accuracy of 0.01 mm. Statistical analysis was carried out by SPSS (SPSS Inc., Chicago, IL, USA) using t-test and repeated-measures ANOVA. Statistical significance was defined at P<0.05. After each water storage period, the acrylic specimens produced by injection exhibited less dimensional changes compared to those produced by the conventional technique. Curing shrinkage was compensated by water sorption with an increase in water storage time decreasing dimensional changes. Within the limitations of this study, dimensional changes of acrylic resin specimens were influenced by the molding technique used and SR-Ivocap injection procedure exhibited higher dimensional accuracy compared to conventional molding.

Surface roughness of glass ionomer cements indicated for uncooperative patients according to surface protection treatment

PubMed Central

Pacifici, Edoardo; Bossù, Maurizio; Giovannetti, Agostino; La Torre, Giuseppe; Guerra, Fabrizio; Polimeni, Antonella

2013-01-01

Summary Background Even today, use of Glass Ionomer Cements (GIC) as restorative material is indicated for uncooperative patients. Aim The study aimed at estimating the surface roughness of different GICs using or not their proprietary surface coatings and at observing the interfaces between cement and coating through SEM. Materials and methods Forty specimens have been obtained and divided into 4 groups: Fuji IX (IX), Fuji IX/G-Coat Plus (IXC), Vitremer (V), Vitremer/Finishing Gloss (VFG). Samples were obtained using silicone moulds to simulate class I restorations. All specimens were processed for profilometric evaluation. The statistical differences of surface roughness between groups were assessed using One-Way Analysis of Variance (One-Way ANOVA) (p<0.05). The Two-Way Analysis of Variance (Two-Way ANOVA) was used to evaluate the influence of two factors: restoration material and presence of coating. Coated restoration specimens (IXC and VFG) were sectioned perpendicular to the restoration surface and processed for SEM evaluation. Results No statistical differences in roughness could be noticed between groups or factors. Following microscopic observation, interfaces between restoration material and coating were better for group IXC than for group VFG. Conclusions When specimens are obtained simulating normal clinical procedures, the presence of surface protection does not significantly improve the surface roughness of GICs. PMID:24611090

Surface roughness of glass ionomer cements indicated for uncooperative patients according to surface protection treatment.

PubMed

Pacifici, Edoardo; Bossù, Maurizio; Giovannetti, Agostino; La Torre, Giuseppe; Guerra, Fabrizio; Polimeni, Antonella

2013-01-01

Even today, use of Glass Ionomer Cements (GIC) as restorative material is indicated for uncooperative patients. The study aimed at estimating the surface roughness of different GICs using or not their proprietary surface coatings and at observing the interfaces between cement and coating through SEM. Forty specimens have been obtained and divided into 4 groups: Fuji IX (IX), Fuji IX/G-Coat Plus (IXC), Vitremer (V), Vitremer/Finishing Gloss (VFG). Samples were obtained using silicone moulds to simulate class I restorations. All specimens were processed for profilometric evaluation. The statistical differences of surface roughness between groups were assessed using One-Way Analysis of Variance (One-Way ANOVA) (p<0.05). The Two-Way Analysis of Variance (Two-Way ANOVA) was used to evaluate the influence of two factors: restoration material and presence of coating. Coated restoration specimens (IXC and VFG) were sectioned perpendicular to the restoration surface and processed for SEM evaluation. No statistical differences in roughness could be noticed between groups or factors. Following microscopic observation, interfaces between restoration material and coating were better for group IXC than for group VFG. When specimens are obtained simulating normal clinical procedures, the presence of surface protection does not significantly improve the surface roughness of GICs.

3D geometry measurement of hot cylindric specimen using structured light

NASA Astrophysics Data System (ADS)

Quentin, Lorenz; Beermann, Rüdiger; Pösch, Andreas; Reithmeier, Eduard; Kästner, Markus

2017-06-01

We present a fringe projection system to measure glowing hot hybrid components in between production processes. For this a high power green light projector, based on TI DLP technology, is used to create the highest possible contrast between fringes on the red glowing specimen. It has a resolution of 1140 x 912 pixels with a maximum frame rate of 120 images per second for fast measurement. We use a green bandpass filter (525 nm) on the camera lens to block unwanted incoming radiation from the specimen caused by self-emission. Commercial measurement standards are not calibrated for temperatures other than 20° C, so they cannot be used to validate measurement data at the required temperatures of up to 1000°C since thermal expansion invalidates the geometry specification from the calibration data sheet. In our first development we use a uniformly heated pipe made of stainless steel as a dummy specimen to examine the measured geometry data. A pyrometer measures the temperature of the pipe so the expansion can be easily calculated using the thermal expansion coefficient. Different impact and triangulation angles are investigated to identify the effects of hot ambient air on the measurement. The impact of the induced refractive index gradient is examined to check the need for pre-processing steps in the measurement routine.

Dimensional Changes of Acrylic Resin Denture Bases: Conventional Versus Injection-Molding Technique

PubMed Central

Gharechahi, Jafar; Asadzadeh, Nafiseh; Shahabian, Foad; Gharechahi, Maryam

2014-01-01

Objective: Acrylic resin denture bases undergo dimensional changes during polymerization. Injection molding techniques are reported to reduce these changes and thereby improve physical properties of denture bases. The aim of this study was to compare dimensional changes of specimens processed by conventional and injection-molding techniques. Materials and Methods: SR-Ivocap Triplex Hot resin was used for conventional pressure-packed and SR-Ivocap High Impact was used for injection-molding techniques. After processing, all the specimens were stored in distilled water at room temperature until measured. For dimensional accuracy evaluation, measurements were recorded at 24-hour, 48-hour and 12-day intervals using a digital caliper with an accuracy of 0.01 mm. Statistical analysis was carried out by SPSS (SPSS Inc., Chicago, IL, USA) using t-test and repeated-measures ANOVA. Statistical significance was defined at P<0.05. Results: After each water storage period, the acrylic specimens produced by injection exhibited less dimensional changes compared to those produced by the conventional technique. Curing shrinkage was compensated by water sorption with an increase in water storage time decreasing dimensional changes. Conclusion: Within the limitations of this study, dimensional changes of acrylic resin specimens were influenced by the molding technique used and SR-Ivocap injection procedure exhibited higher dimensional accuracy compared to conventional molding. PMID:25584050

Research on residual stress inside Fe-Mn-Si shape memory alloy coating by laser cladding processing

NASA Astrophysics Data System (ADS)

Ju, Heng; Lin, Cheng-xin; Zhang, Jia-qi; Liu, Zhi-jie

2016-09-01

The stainless Fe-Mn-Si shape memory alloy (SMA) coating was prepared on the surface of AISI 304 stainless steel. The principal residual stress measured by the mechanical hole-drilling method indicates that the Fe-Mn-Si SMA cladding specimen possesses a lower residual stress compared with the 304 stainless steel cladding specimen. The mean stress values of the former and the latter on 10-mm-thick substrate are 4.751 MPa and 7.399 MPa, respectively. What's more, their deformation values on 2-mm-thick substrate are about 0° and 15°, respectively. Meanwhile, the variation trend and the value of the residual stress simulated by the ANSYS finite element software consist with experimental results. The X-ray diffraction (XRD) pattern shows ɛ-martensite exists in Fe-Mn-Si SMA coating, which verifies the mechanism of low residual stress. That's the γ→ɛ martensite phase transformation, which relaxes the residual stress of the specimen and reduces its deformation in the laser cladding processing.

Latex agglutination inhibition card test for gentamicin assay: clinical evaluation and comparison with radioimmunoassay and bioassay.

PubMed Central

Standiford, H C; Bernstein, D; Nipper, H C; Caplan, E; Tatem, B; Hall, J S; Reynolds, J

1981-01-01

Gentamicin levels were determined in 100 serum specimens by a new latex agglutination inhibition card test, a radioimmunoassay (RIA), and a bioassay. Correlation coefficients determined by linear regression analysis demonstrated that the levels obtained by the latex agglutination inhibition card test had a high degree of correlation with the RIA and could be performed much faster and more economically when processing small numbers of specimens. The bioassay had a slightly lower degree of correlation with both the RIA and the latex test and was adversely influenced by concurrently administered antibiotics which could not be eliminated by beta-lactamase. When measuring gentamicin concentrations above 2 micrograms/ml, the coefficient of variation was less than 14% for the latex agglutination assay compared with 15% for the bioassay and 12% for RIA. The latex agglutination inhibition card test is a rapid, accurate, specific, and reproducible method for monitoring gentamicin levels in patients and is particularly applicable for laboratories processing small numbers of specimens. PMID:7247384

The effect of annealing temperature on the properties of powder metallurgy processed Ti-35Nb-2Zr-0.5O alloy.

PubMed

Málek, Jaroslav; Hnilica, František; Veselý, Jaroslav; Smola, Bohumil; Medlín, Rostislav

2017-11-01

Ti-35Nb-2Zr-0.5O (wt%) alloy was prepared via a powder metallurgy process (cold isostatic pressing of blended elemental powders and subsequent sintering) with the primary aim of using it as a material for bio-applications. Sintered specimens were swaged and subsequently the influence of annealing temperature on the mechanical and structural properties was studied. Specimens were annealed at 800, 850, 900, 950, and 1000°C for 0.5h and water quenched. Significant changes in microstructure (i.e. precipitate dissolution or grain coarsening) were observed in relation to increasing annealing temperature. In correlation with those changes, the mechanical properties were also studied. The ultimate tensile strength increased from 925MPa (specimen annealed at 800°C) to 990MPa (900°C). Also the elongation increased from ~ 13% (800°C) to more than 20% (900, 950, and 1000°C). Copyright © 2017 Elsevier Ltd. All rights reserved.

In situ TEM Raman spectroscopy and laser-based materials modification.

PubMed

Allen, F I; Kim, E; Andresen, N C; Grigoropoulos, C P; Minor, A M

2017-07-01

We present a modular assembly that enables both in situ Raman spectroscopy and laser-based materials processing to be performed in a transmission electron microscope. The system comprises a lensed Raman probe mounted inside the microscope column in the specimen plane and a custom specimen holder with a vacuum feedthrough for a tapered optical fiber. The Raman probe incorporates both excitation and collection optics, and localized laser processing is performed using pulsed laser light delivered to the specimen via the tapered optical fiber. Precise positioning of the fiber is achieved using a nanomanipulation stage in combination with simultaneous electron-beam imaging of the tip-to-sample distance. Materials modification is monitored in real time by transmission electron microscopy. First results obtained using the assembly are presented for in situ pulsed laser ablation of MoS 2 combined with Raman spectroscopy, complimented by electron-beam diffraction and electron energy-loss spectroscopy. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of failure processes in tungsten copper composites under fatigue loading conditions

NASA Technical Reports Server (NTRS)

Kim, Yong-Suk; Verrilli, Michael J.; Gabb, Timothy P.

1989-01-01

A fractographic and metallographic investigation was performed on specimens of a tungsten fiber reinforced copper matrix composite (9 vol percent), which had experienced fatigue failures at elevated temperatures. Major failure modes and possible failure mechanisms, with an emphasis placed on characterizing fatigue damage accumulation, were determined. Metallography of specimens fatigued under isothermal cyclic loading suggested that fatigue damage initiates in the matrix. Cracks nucleated within the copper matrix at grain boundaries, and they propagated through cavity coalescence. The growing cracks subsequently interacted with the reinforcing tungsten fibers, producing a localized ductile fiber failure. Examinations of interrupted tests before final failure confirmed the suggested fatigue damage processes.

Microgravity

NASA Image and Video Library

1992-06-25

Zeolites are crystalline aluminosilicates that have complex framework structures. However, there are several features of zeolite crystals that make unequivocal structure determinations difficult. The acquisition of reliable structural information on zeolites is greatly facilitated by the availability of high-quality specimens. For structure determinations by conventional diffraction techniques, large single-crystal specimens are essential. Alternatively, structural determinations by powder profile refinement methods relax the constraints on crystal size, but still require materials with a high degree of crystalline perfection. Studies conducted at CAMMP (Center for Advanced Microgravity Materials Processing) have demonstrated that microgravity processing can produce larger crystal sizes and fewer structural defects relative to terrestrial crystal growth. Principal Investigator: Dr. Albert Sacco

Zeolites

NASA Technical Reports Server (NTRS)

1992-01-01

Zeolites are crystalline aluminosilicates that have complex framework structures. However, there are several features of zeolite crystals that make unequivocal structure determinations difficult. The acquisition of reliable structural information on zeolites is greatly facilitated by the availability of high-quality specimens. For structure determinations by conventional diffraction techniques, large single-crystal specimens are essential. Alternatively, structural determinations by powder profile refinement methods relax the constraints on crystal size, but still require materials with a high degree of crystalline perfection. Studies conducted at CAMMP (Center for Advanced Microgravity Materials Processing) have demonstrated that microgravity processing can produce larger crystal sizes and fewer structural defects relative to terrestrial crystal growth. Principal Investigator: Dr. Albert Sacco

Enhanced Densification and Hardness of Titanium Bodies Sintered by Advanced Hydrogen Sintering Process

NASA Astrophysics Data System (ADS)

Oh, Jung-Min; Koo, Ja-Geon; Lim, Jae-Won

2018-05-01

A new sintering technique for enhancing a densification and hardness of sintered titanium body by supplying hydrogen was developed (Hydrogen Sintering Process, HSP). The HSP was developed by only injecting hydrogen into an argon atmosphere during the core time. As a result, sound titanium sintered bodies with high density and hardness were obtained by the HSP. In addition, a pore size and number of the HSP specimens were smaller than those of the argon atmosphere specimen. It was found that the injecting hydrogen into the argon atmosphere by HSP can prevent the formation of oxide layers, resulting in enhanced densification and hardness.

Automated Tow Placement Processing and Characterization of Composites

NASA Technical Reports Server (NTRS)

Prabhakaran, R.

2004-01-01

The project had one of the initial objectives as automated tow placement (ATP), in which a robot was used to place a collimated band of pre-impregnated ribbons or a wide preconsolidated tape onto a tool surface. It was proposed to utilize the Automated Tow Placement machine that was already available and to fabricate carbon fiber reinforced PEEK (polyether-ether-ketone) matrix composites. After initial experiments with the fabrication of flat plates, composite cylinders were to be fabricated. Specimens from the fabricated parts were to be tested for mechanical characterization. A second objective was to conduct various types of tests for characterizing composite specimens cured by different fabrication processes.

Rapid adhesive bonding of advanced composites and titanium

NASA Technical Reports Server (NTRS)

Stein, B. A.; Tyeryart, J. R.; Hodgest, W. T.

1985-01-01

Rapid adhesive bonding (RAB) concepts utilize a toroid induction technique to heat the adhesive bond line directly. This technique was used to bond titanium overlap shear specimens with 3 advanced thermoplastic adhesives and APC-2 (graphite/PEEK) composites with PEEK film. Bond strengths equivalent to standard heated-platen press bonds were produced with large reductions in process time. RAB produced very strong bonds in APC-2 adherend specimens; the APC-2 adherends were highly resistant to delamination. Thermal cycling did not significantly affect the shear strengths of RAB titanium bonds with polyimide adhesives. A simple ultrasonic non-destructive evaluation process was found promising for evaluating bond quality.

On impedance measurement of reinforced concrete on the surface for estimate of corroded rebar

NASA Astrophysics Data System (ADS)

Sasamoto, Akira; Yu, Jun; Harada, Yoshihisa; Iwata, Masahiro; Noguchi, Kazuhiro

2017-04-01

In an estimate of health monitoring for reinforced concrete, corrosion degree of rebar is important parameter but is not easy to be estimated by non destructive testing. A few test method such as half cell method or polarization resistance method could be a 'perfect' nondestructive method if luckily having had wired connection to rebar without destructing target concrete. In this presentation it is reported the experimental result that an impedance measurement on surface of reinforced concretes is able to distinguish corroded rebar from healthy rebar. The contact electrode on concrete surface are simple structure made of urethane sponge and needle. Impedance measurement are carried out with frequency response analyzer with frequency range from 0.01Hz to 1MHz, typical amplitude of imposed voltage are 10 volt. We made concrete specimens under two different corrosion process. One process(pre corrosion) has rebars corroded by electrolysis in salty water before concrete casting and another process (post corrosion) has concrete specimens being corroded during the curing. The results of application of developed method to these corroded specimens show the method is useful to estimate corrosion level of rebars.

[Effect of fluoride concentration on the corrosion behavior of cobalt-chromium alloy fabricated by two different technology processes].

PubMed

Qiuxia, Yang; Ying, Yang; Han, Xu; Di, Wu; Ke, Guo

2016-02-01

This study aims to determine the effect of fluoride concentration on the corrosion behavior of cobalt-chromium alloy fabricated by two different technology processes in a simulated oral environment. A total of 15 specimens were employed with selective laser melting (SLM) and another 15 for traditional casting (Cast) in cobalt-chromium alloy powders and blocks with the same material composition. The corrosion behavior of the specimens was studied by potentiodynamic polarization test under different oral environments with varying solubilities of fluorine (0, 0.05%, and 0.20% for each) in acid artificial saliva (pH = 5.0). The specimens were soaked in fluorine for 24 h, and the surface microstructure was observed under a field emission scanning electron microscope after immersing the specimens in the test solution at constant temperature. The corrosion potential (Ecorr) value of the cobalt-chromium alloy cast decreased with increasing fluoride concentration in acidic artificial saliva. The Ecorr, Icorr, and Rp values of the cobalt-chromium alloy fabricated by two different technology processes changed significantly when the fluoride concentration was 0.20% (P < 0.05). The Ecorr, Icorr, and Rp values of the cobalt-chromium alloy fabricated by two different technology processes exhibited a statistically significant difference. The Icorr value of the cobalt-chromium alloy cast was higher than that in the SLM group cobalt-chromium alloy when the fluoride concentration was 0.20% (P < 0.05). The Ecorr, tRp alues of the cobalt-chromium alloy cast were lower htan those of the SLM group cobalt-chromium alloy when the fluoride concentration was 0.20% (P< 0 .05). Fluoride ions adversely affected the corrosion resistance of the cobalt-chromium alloy fabricated by two different technology processes. The corrosion resistance of the cobalt-chromium alloy cast was worse than that of the SLM group cobalt-chromium alloy when the fluoride concentration was 0.20%.

Novel Bonding Technology for Hermetically Sealed Silicon Micropackage

NASA Astrophysics Data System (ADS)

Lee, Duck-Jung; Ju, Byeong-Kwon; Choi, Woo-Beom; Jeong, Jee-Won; Lee, Yun-Hi; Jang, Jin; Lee, Kwang-Bae; Oh, Myung-Hwan

1999-01-01

We performed glass-to-silicon bonding and fabricated a hermetically sealed silicon wafer using silicon direct bonding followed by anodic bonding (SDAB). The hydrophilized glass and silicon wafers in solution were dried and initially bonded in atmosphere as in the silicon direct bonding (SDB) process, but annealing at high temperature was not performed. Anodic bonding was subsequently carried out for the initially bonded specimens. Then the wafer pairs bonded by the SDAB method were different from those bonded by the anodic bonding process only. The effects of the bonding process on the bonded area and tensile strength were investigated as functions of bonding temperature and voltage. Using scanning electron microscopy (SEM), the cross-sectional view of the bonded interface region was observed. In order to investigate the migration of the sodium ions in the bonding process, the concentration of the bonded glass was compared with that of standard glass. The specimen bonded using the SDAB process had higher efficiency than that using the anodic bonding process only.

[Effect of preparation methods on the metal-porcelain bond strength of Co-Cr alloys].

PubMed

Liu, Jie; Chi, Shuai; Xu, Jin; Wang, Yanyan; Zhan, Desong

2014-04-01

To compare the shear bond strength(SBS) of cast Co-Cr alloys and selective laser melting(SLM) Co-Cr alloys with those of dental porcelain. A dental porcelain (Vita) was applied on cast and SLM Co-Cr alloy specimens (n = 10). SBS test was conducted, and fracture mode analysis was determined. Student's t-test by SPSS 13.0 software was employed to analyze the data. The SLM Co-Cr alloy specimens had lower SBS values than the cast Co-Cr alloy specimens (P > 0.05). The metal-porcelain bond strength value of the cast group was (33.11 +/- 4.98) MPa, and that of the SLM group was (30.94 +/- 5.98) MPa. The specimens in both test groups exhibited mixed failure. The metal-porcelain system processed by SLM exhibit a bond strength that is similar to that of the cast group. This system also display a high precision.

Notched Strength Allowables and Inplane Shear Strength of AS4/VRM-34 Textile Laminates

NASA Technical Reports Server (NTRS)

Grenoble, Ray W.; Johnston, William M.

2013-01-01

Notched and unnotched strength allowables were developed for a textile composite to provide input data to analytical structural models based on the Pultruded Rod Stiffened Efficient Unitized Structure (PRSEUS) concept. Filled-hole tensile strength, filled-hole compressive strength, and inplane shear strength along stitch lines have been measured. The material system evaluated in this study is based on warp-knitted preforms of AS4 carbon fibers and VRM-34 epoxy resin, which have been processed via resin infusion and oven curing. All specimens were tested in as-fabricated (dry) condition. Filled-hole strengths were evaluated with and without through-thickness stitching. The effects of scaling on filled-hole tensile strength were evaluated by testing specimens in two widths, but with identical width / hole-diameter ratios. Inplane shear specimens were stitched in two configurations, and two specimen thicknesses were tested for each stitch configuration.

In vitro evaluation of marginal adaptation in five ceramic restoration fabricating techniques.

PubMed

Ural, Cağri; Burgaz, Yavuz; Saraç, Duygu

2010-01-01

To compare in vitro the marginal adaptation of crowns manufactured using ceramic restoration fabricating techniques. Fifty standardized master steel dies simulating molars were produced and divided into five groups, each containing 10 specimens. Test specimens were fabricated with CAD/CAM, heat-press, glass-infiltration, and conventional lost-wax techniques according to manufacturer instructions. Marginal adaptation of the test specimens was measured vertically before and after cementation using SEM. Data were statistically analyzed by one-way ANOVA with Tukey HSD tests (a = .05). Marginal adaptation of ceramic crowns was affected by fabrication technique and cementation process (P < .001). The lowest marginal opening values were obtained with Cerec-3 crowns before and after cementation (P < .001). The highest marginal discrepancy values were obtained with PFM crowns before and after cementation. Marginal adaptation values obtained in the compared systems were within clinically acceptable limits. Cementation causes a significant increase in the vertical marginal discrepancies of the test specimens.

Effect of CrO3 Sealing Time on Anodized A12024-T3

NASA Astrophysics Data System (ADS)

Korda, Akhmad A.; Hidayat, R. Z.

2016-08-01

The effect of CrO3 sealing time on anodized aluminum alloy has been investigated. A1 2024-T3 were used as substrate. Anodizing was carried out using chromic acid. CrO3 sealing was conducted in CrO3 solution for 30, 60, 90, 120 and 150 minutes. As comparison, other specimens were also prepared as anodized and boiled water sealing. Thickness of the coating was observed by optical microscope. Anodized and sealing layer was analyzed by X- ray diffraction. The hardness of as anodized, boiled water sealing and CrO3 sealing were compared. The highest hardness is achieved by CrO3 sealed specimen and followed by boiled water sealing and as anodized specimens. The longer the processes of CrO3 sealing the higher layer thickness and therefore the higher hardness of the oxide layer. The best resistance to electrolyte penetration is achieved by the CrO3 sealed specimen followed by boiled water sealed and as anodized specimens. The higher thickness of oxide layer, the higher the resistance against electrolyte penetration.

Sizing Single Cantilever Beam Specimens for Characterizing Facesheet/Core Peel Debonding in Sandwich Structure

NASA Technical Reports Server (NTRS)

Ratcliffe, James G.

2010-01-01

This technical publication details part of an effort focused on the development of a standardized facesheet/core peel debonding test procedure. The purpose of the test is to characterize facesheet/core peel in sandwich structure, accomplished through the measurement of the critical strain energy release rate associated with the debonding process. Following an examination of previously developed tests and a recent evaluation of a selection of these methods, a single cantilever beam (SCB) specimen was identified as being a promising candidate for establishing such a standardized test procedure. The objective of the work described here was to begin development of a protocol for conducting a SCB test that will render the procedure suitable for standardization. To this end, a sizing methodology was developed to ensure appropriate SCB specimen dimensions are selected for a given sandwich system. Application of this method to actual sandwich systems yielded SCB specimen dimensions that would be practical for use. This study resulted in the development of a practical SCB specimen sizing method, which should be well-suited for incorporation into a standardized testing protocol.

Does Formaldehyde Increase Cell Free DNA in Maternal Plasma Specimens?

PubMed

Jacob, Rintu R; Saxena, Renu; Verma, Ishwar C

2016-11-01

There have been conflicting observations reported in the literature regarding the effects of formaldehyde in the recovery of cell free fetal DNA (CFF DNA) from maternal plasma. The aim of the present study was to assess the effect of formaldehyde treatment on circulating cell free DNA. We conducted this study using blood specimens collected from 11 pregnant women, each of whom was carrying a male fetus. DYS14 and HBB real time assays were performed to quantify fetal and total circulating cell free DNA from formaldehyde treated and untreated maternal plasma specimens, respectively. The concentration of total circulating cell free DNA in formaldehyde-treated maternal plasma was reduced, compared with untreated maternal plasma (n = 11; P = .02). The percentage of CFF DNA between formaldehyde-treated and untreated maternal plasma specimens did not differ significantly (n = 11; P = .15). Addition of formaldehyde does not significantly enhance the proportion of cell free fetal DNA when blood specimens are processed without delay. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Manufacturing of High Porosity Iron with an Ultra-Fine Microstructure via Free Pressureless Spark Plasma Sintering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Guodong; Wei, Xialu; Olevsky, Eugene

2016-06-01

High porosity (>40 vol %) iron specimens with micro- and nanoscale isotropic pores were fabricated by carrying out free pressureless spark plasma sintering (FPSPS) of submicron hollow Fe–N powders at 750 °C. Ultra-fine porous microstructures are obtained by imposing high heating rates during the preparation process. This specially designed approach not only avoids the extra procedures of adding and removing space holders during the formation of porous structures, but also triggers the continued phase transitions of the Fe–N system at relatively lower processing temperatures. In conclusion, the compressive strength and energy absorption characteristics of the FPSPS processed specimens are examinedmore » here to be correspondingly improved as a result of the refined microstructure.« less

Determination of Dynamic Recrystallization Process by Equivalent Strain

NASA Astrophysics Data System (ADS)

Qin, Xiaomei; Deng, Wei

Based on Tpнoвckiй's displacement field, equivalent strain expression was derived. And according to the dynamic recrystallization (DRX) critical strain, DRX process was determined by equivalent strain. It was found that equivalent strain distribution in deformed specimen is inhomogeneous, and it increases with increasing true strain. Under a certain true strain, equivalent strains at the center, demisemi radius or on tangential plane just below the surface of the specimen are higher than the true strain. Thus, micrographs at those positions can not exactly reflect the true microstructures under the certain true strain. With increasing strain rate, the initial and finish time of DRX decrease. The frozen microstructures of 20Mn23AlV steel with the experimental condition validate the feasibility of predicting DRX process by equivalent strain.

Preservation of Fine-Needle Aspiration Specimens for Future Use in RNA-Based Molecular Testing

PubMed Central

Ladd, Amy C.; O'Sullivan-Mejia, Emerald; Lea, Tasha; Perry, Jessica; Dumur, Catherine I.; Dragoescu, Ema; Garrett, Carleton T.; Powers, Celeste N.

2015-01-01

Background The application of ancillary molecular testing is becoming more important for the diagnosis and classification of disease. The use of fine-needle aspiration (FNA) biopsy as the means of sampling tumors in conjunction with molecular testing could be a powerful combination. FNA is minimally invasive, cost effective, and usually demonstrates accuracy comparable to diagnoses based on excisional biopsies. Quality control (QC) and test validation requirements for development of molecular tests impose a need for access to pre-existing clinical samples. Tissue banking of excisional biopsy specimens is frequently performed at large research institutions, but few have developed protocols for preservation of cytologic specimens. This study aimed to evaluate cryopreservation of FNA specimens as a method of maintaining cellular morphology and ribonucleic acid (RNA) integrity in banked tissues. Methods FNA specimens were obtained from fresh tumor resections, processed by using a cryopreservation protocol, and stored for up to 27 weeks. Upon retrieval, samples were made into slides for morphological evaluation, and RNA was extracted and assessed for integrity by using the Agilent Bioanalyzer (Agilent Technologies, Santa Clara, Calif). Results Cryopreserved specimens showed good cell morphology and, in many cases, yielded intact RNA. Cases showing moderate or severe RNA degradation could generally be associated with prolonged specimen handling or sampling of necrotic areas. Conclusions FNA specimens can be stored in a manner that maintains cellular morphology and RNA integrity necessary for studies of gene expression. In addition to addressing quality control (QC) and test validation needs, cytology banks will be an invaluable resource for future molecular morphologic and diagnostic research studies. PMID:21287691

Corrosion resistance characteristics of a Ti-6Al-4V alloy scaffold that is fabricated by electron beam melting and selective laser melting for implantation in vivo.

PubMed

Zhao, Bingjing; Wang, Hong; Qiao, Ning; Wang, Chao; Hu, Min

2017-01-01

The purpose of this study is to determine the corrosion resistance of Ti-6Al-4V alloy fabricated with electron beam melting and selective laser melting for implantation in vivo. Ti-6Al-4V alloy specimens were fabricated with electron beam melting (EBM) and selective laser melting (SLM). A wrought form of Ti-6Al-4V alloy was used as a control. Surface morphology observation, component analysis, corrosion resistance experimental results, electrochemical impedance spectroscopy, crevice corrosion resistance experimental results, immersion test and metal ions precipitation analysis were processed, respectively. The thermal stability of EBM specimen was the worst, based on the result of open circuit potential (OCP) result. The result of electrochemical impedance spectroscopy indicated that the corrosion resistance of the SLM specimen was the best under the low electric potential. The result of potentiodynamic polarization suggested that the corrosion resistance of the SLM specimen was the best under the low electric potential (<1.5V) and EBM specimen was the best under the high electric potential (>1.5V).The crevice corrosion resistance of the EBM specimen was the best. The corrosion resistance of SLM specimen was the best, based on the result of immersion test. The content of Ti, Al and V ions of EBM, SLM and wrought specimens was very low. In general, the scaffolds that were fabricated with EBM and SLM had good corrosion resistance, and were suitable for implantation in vivo. Copyright © 2016 Elsevier B.V. All rights reserved.

Shape memory characteristics and mechanical properties of powder metallurgy processed Ti50Ni40Cu10 alloy.

PubMed

Kim, Yeon-Wook

2014-10-01

Ti-Ni-Cu alloy powders were prepared by gas atomization and porous bulk specimens were fabricated by spark plasma sintering (SPS). The microstructure of as-solidified powders exhibited a cellular structure and they contained a high density of nano-sized porosities which were located in the intercellular regions. XRD analysis showed that one-step martensitic transformation of B2-B19 occurred in all alloy powders and SPS specimens. When the martensitic transformation start temperature (M(s)) and austenite transformation finish temperature (A(f)) were determined in order to analyze the dependence of powder size on transformation temperatures, the M(s) increased slightly from -17.5 degrees C to - 14.6 degrees C as increasing the powder size ranging from between 25 and 50 μm to ranging between 100 and 150 μm. However, the M(s) and A(f) of the as-atomized powders is much smaller than those of SPS specimens and the M(s) of porous specimen was about 10.9 degrees C. Loading-unloading compressive tests were carried out to investigate the mechanical properties of porous Ti-Ni-Cu specimen. The specimen was compressed to the strain of 6% at a temperature higher than A,. After unloading, the residual strain was 2.1%. After the compressed specimen was heated to 60 degrees C and held for 30 minutes and then cooled to room temperature, the changes in the length of the specimens were measured. Then it was found that the recovered strain ascribed to shape memory effect was 1.5%.

Spotiton: A prototype for an integrated inkjet dispense and vitrification system for cryo-TEM

PubMed Central

Jain, Tilak; Sheehan, Patrick; Crum, John; Carragher, Bridget; Potter, Clinton S.

2012-01-01

Over the last three decades, Cryo-TEM has developed into a powerful technique for high-resolution imaging of biological macromolecules in their native vitrified state. However, the technique for vitrifying specimens onto EM grids is essentially unchanged – application of ~ 3 µL sample to a grid, followed by blotting and rapid plunge freezing into liquid ethane. Several trials are often required to obtain suitable thin (few hundred nanometers or less) vitrified layers amenable for cryo-TEM imaging, which results in waste of precious sample and resources. While commercially available instruments provide some level of automation to control the vitrification process in an effort to increase quality and reproducibility, obtaining satisfactory vitrified specimens remains a bottleneck in the Cryo-TEM pipeline. We describe here a completely novel method for EM specimen preparation based on small volume (picoliter to nanoliter) dispensing using inkjet technology. A first prototype system (Spotiton v0.5) demonstrates feasibility of this new approach for specimen vitrification. A piezo-electric inkjet dispenser is integrated with optical real-time cameras (100 Hz frame rate) to analyze picoliter to nanoliter droplet profiles in-flight and spreading dynamics on the grid, and thus provides a method to optimize timing of the process. Using TEM imaging and biochemical assays we demonstrate that the piezo-electric inkjet mechanism does not disrupt the structural or functional integrity of macromolecules. These preliminary studies provide insight into the factors and components that will need further development to enable a robust and repeatable technique for specimen vitrification using this novel approach. PMID:22569522

Fatigue Performance of Ti-6Al-4V Additively Manufactured Specimens with Integrated Capillaries of an Embedded Structural Health Monitoring System

PubMed Central

Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter; Devesse, Wim; De Graeve, Iris; Terryn, Herman; Guillaume, Patrick

2017-01-01

Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the reference specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored. PMID:28841186

Fatigue Performance of Ti-6Al-4V Additively Manufactured Specimens with Integrated Capillaries of an Embedded Structural Health Monitoring System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter

Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the referencemore » specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored.« less

Fatigue Performance of Ti-6Al-4V Additively Manufactured Specimens with Integrated Capillaries of an Embedded Structural Health Monitoring System

DOE PAGES

Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter; ...

2017-08-25

Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the referencemore » specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored.« less

The effect of aging treatment on the fracture toughness and impact strength of injection molded Ni-625 superalloy parts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Özgün, Özgür, E-mail: oozgun@bingol.edu.tr; Yılmaz, Ramazan; Özkan Gülsoy, H.

In this study, the effect of aging heat treatment on fracture toughness and impact strength of Ni-625 superalloy fabricated by using powder injection molding (PIM) method was examined. After a feedstock was prepared by mixing the prealloyed Ni-625 superalloy powder, which was fabricated by gas atomisation, with a polymeric binder system and then it was granulated, it was shaped through the use of injection. The molded specimens were sintered at 1300 °C for 3 h after a two-stage debinding process. Once the sintered specimens were treated in the solution at 1150 °C for 2 h, they were quenched. Aging treatmentmore » was performed by keeping specimens at 745 °C for 22 h. Fracture toughness and impact tests were performed on sintered and aged specimens. Microstructure examinations were performed by using optical microscope, scanning electron microscope, and transmission electron microscope. The results revealed that aging heat treatment led to the formation of some carbides and intermetallic phases in the microstructure. While the hardness of the aged specimens increased due to these phases, their fracture toughness and impact strength values decreased. - Highlights: • Ni-625 superalloy components were produced by means of powder injection molding. • The produced components were subjected to aging treatment. • Aging process provided approximately 50% increase in the hardness of components. • Intermetallic precipitates, carbides and TCP phases occurred within the aged parts. • Fracture toughness and impact strength values decreased due to the hard phases.« less

Active sensors for health monitoring of aging aerospace structures

NASA Astrophysics Data System (ADS)

Giurgiutiu, Victor; Redmond, James M.; Roach, Dennis P.; Rackow, Kirk

2000-06-01

A project to develop non-intrusive active sensors that can be applied on existing aging aerospace structures for monitoring the onset and progress of structural damage (fatigue cracks and corrosion) is presented. The state of the art in active sensors structural health monitoring and damage detection is reviewed. Methods based on (a) elastic wave propagation and (b) electro-mechanical (E/M) impedance technique are cited and briefly discussed. The instrumentation of these specimens with piezoelectric active sensors is illustrated. The main detection strategies (E/M impedance for local area detection and wave propagation for wide area interrogation) are discussed. The signal processing and damage interpretation algorithms are tuned to the specific structural interrogation method used. In the high frequency E/M impedance approach, pattern recognition methods are used to compare impedance signatures taken at various time intervals and to identify damage presence and progression from the change in these signatures. In the wave propagation approach, the acousto- ultrasonic methods identifying additional reflection generated from the damage site and changes in transmission velocity and phase are used. Both approaches benefit from the use of artificial intelligence neural networks algorithms that can extract damage features based on a learning process. Design and fabrication of a set of structural specimens representative of aging aerospace structures is presented. Three built-up specimens, (pristine, with cracks, and with corrosion damage) are used. The specimen instrumentation with active sensors fabricated at the University of South Carolina is illustrated. Preliminary results obtained with the E/M impedance method on pristine and cracked specimens are presented.

Preparation of viral samples within biocontainment for ultrastructural analysis: Utilization of an innovative processing capsule for negative staining.

PubMed

Monninger, Mitchell K; Nguessan, Chrystal A; Blancett, Candace D; Kuehl, Kathleen A; Rossi, Cynthia A; Olschner, Scott P; Williams, Priscilla L; Goodman, Steven L; Sun, Mei G

2016-12-01

Transmission electron microscopy can be used to observe the ultrastructure of viruses and other microbial pathogens with nanometer resolution. In a transmission electron microscope (TEM), the image is created by passing an electron beam through a specimen with contrast generated by electron scattering from dense elements in the specimen. Viruses do not normally contain dense elements, so a negative stain that places dense heavy metal salts around the sample is added to create a dark border. To prepare a virus sample for a negative stain transmission electron microscopy, a virus suspension is applied to a TEM grid specimen support, which is a 3mm diameter fragile specimen screen coated with a few nanometers of plastic film. Then, deionized (dI) water rinses and a negative stain solution are applied to the grid. All infectious viruses must be handled in a biosafety cabinet (BSC) and many require a biocontainment laboratory environment. Staining viruses in biosafety levels (BSL) 3 and 4 is especially challenging because the support grids are small, fragile, and easily moved by air currents. In this study we evaluated a new device for negative staining viruses called mPrep/g capsule. It is a capsule that holds up to two TEM grids during all processing steps and for storage after staining is complete. This study reports that the mPrep/g capsule method is valid and effective to negative stain virus specimens, especially in high containment laboratory environments. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Fatigue Performance of Ti-6Al-4V Additively Manufactured Specimens with Integrated Capillaries of an Embedded Structural Health Monitoring System.

PubMed

Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter; Devesse, Wim; De Graeve, Iris; Terryn, Herman; Guillaume, Patrick

2017-08-25

Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the reference specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored.

Guidelines for quality assurance and quality control of fish taxonomic data collected as part of the National Water-Quality Assessment Program

USGS Publications Warehouse

Walsh, Stephen Joseph; Meador, Michael R.

1998-01-01

Fish community structure is characterized by the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program as part of a perennial, multidisciplinary approach to evaluating the physical, chemical, and biological conditions of the Nation's water resources. The objective of quality assurance and quality control of fish taxonomic data that are collected as part of the NAWQA Program is to establish uniform guidelines and protocols for the identification, processing, and archiving of fish specimens to ensure that accurate and reliable data are collected. Study unit biologists, collaborating with regional biologists and fish taxonomic specialists, prepare a pre-sampling study plan that includes a preliminary faunal list and identification of an ichthyological curation center for receiving preserved fish specimens. Problematic taxonomic issues and protected taxa also are identified in the study plan, and collecting permits are obtained in advance of sampling activities. Taxonomic specialists are selected to identify fish specimens in the field and to assist in determining what fish specimens should be sacrificed, fixed, and preserved for laboratory identification, independent taxonomic verification, and long-term storage in reference or voucher collections. Quantitative and qualitative sampling of fishes follows standard methods previously established for the NAWQA Program. Common ichthyological techniques are used to process samples in the field and prepare fish specimens to be returned to the laboratory or sent to an institutional repository. Taxonomic identifications are reported by using a standardized list of scientific names that provides nomenclatural consistency and uniformity across study units.

Production of ultrafine grained aluminum by cyclic severe plastic deformation at ambient temperature

NASA Astrophysics Data System (ADS)

Bereczki, P.; Szombathelyi, V.; Krallics, G.

2014-08-01

In the present study the possibilities of grain refinement was investigated by applying large-scale of cyclic plastic deformation to aluminum at ambient temperature. The specimens are processed by multiaxial forging, which is one of the severe plastic deformation techniques. The aim of the experiments with the aluminum alloy 6082M was the determination of the equivalent stress and strain by multiaxial forging and the investigation of evolution of mechanical properties in relation with the accumulated deformation in the specimen. The mechanical properties of raw material was determined by plane strain compression test as well as by hardness measurements. The forming experiments were carried out on Gleeble 3800 physical simulator with MaxStrain System. The mechanical properties of the forged specimens were investigated by micro hardness measurements and tensile tests. A mechanical model, based on the principle of virtual velocities was developed to calculate the flow curves using the measured dimensional changes of the specimen and the measured force. With respect to the evolution of these curves, the cyclic growth of the flow stress can be observed at every characteristic points of the calculated flow curves. In accordance with this tendency, the evolution of the hardness along the middle cross section of the deformed volume has also a nonmonotonous characteristic and the magnitudes of these values are much smaller than by the specimen after plane strain compression test. This difference between the flow stresses respect to the monotonic and non-monotonic deformation can be also observed. The formed microstructure, after a 10-passes multiaxial forging process, consists of mainly equiaxial grains in the submicron grain scale.

The NCBI BioCollections Database

PubMed Central

Sharma, Shobha; Ciufo, Stacy; Starchenko, Elena; Darji, Dakshesh; Chlumsky, Larry; Karsch-Mizrachi, Ilene

2018-01-01

Abstract The rapidly growing set of GenBank submissions includes sequences that are derived from vouchered specimens. These are associated with culture collections, museums, herbaria and other natural history collections, both living and preserved. Correct identification of the specimens studied, along with a method to associate the sample with its institution, is critical to the outcome of related studies and analyses. The National Center for Biotechnology Information BioCollections Database was established to allow the association of specimen vouchers and related sequence records to their home institutions. This process also allows cross-linking from the home institution for quick identification of all records originating from each collection. Database URL: https://www.ncbi.nlm.nih.gov/biocollections PMID:29688360

Systems and methods for laser assisted sample transfer to solution for chemical analysis

DOEpatents

Van Berkel, Gary J.; Kertesz, Vilmos; Ovchinnikova, Olga S.

2014-06-03

Systems and methods are described for laser ablation of an analyte from a specimen and capturing of the analyte in a dispensed solvent to form a testing solution. A solvent dispensing and extraction system can form a liquid microjunction with the specimen. The solvent dispensing and extraction system can include a surface sampling probe. The laser beam can be directed through the surface sampling probe. The surface sampling probe can also serve as an atomic force microscopy probe. The surface sampling probe can form a seal with the specimen. The testing solution including the analyte can then be analyzed using an analytical instrument or undergo further processing.

Systems and methods for laser assisted sample transfer to solution for chemical analysis

DOEpatents

Van Berkel, Gary J.; Kertesz, Vilmos; Ovchinnikova, Olga S.

2015-09-29

Systems and methods are described for laser ablation of an analyte from a specimen and capturing of the analyte in a dispensed solvent to form a testing solution. A solvent dispensing and extraction system can form a liquid microjunction with the specimen. The solvent dispensing and extraction system can include a surface sampling probe. The laser beam can be directed through the surface sampling probe. The surface sampling probe can also serve as an atomic force microscopy probe. The surface sampling probe can form a seal with the specimen. The testing solution including the analyte can then be analyzed using an analytical instrument or undergo further processing.

Systems and methods for laser assisted sample transfer to solution for chemical analysis

DOEpatents

Van Berkel, Gary J; Kertesz, Vilmos; Ovchinnikova, Olga S

2013-08-27

Systems and methods are described for laser ablation of an analyte from a specimen and capturing of the analyte in a dispensed solvent to form a testing solution. A solvent dispensing and extraction system can form a liquid microjunction with the specimen. The solvent dispensing and extraction system can include a surface sampling probe. The laser beam can be directed through the surface sampling probe. The surface sampling probe can also serve as an atomic force microscopy probe. The surface sampling probe can form a seal with the specimen. The testing solution including the analyte can then be analyzed using an analytical instrument or undergo further processing.

Standard Specimen Reference Set: Pancreatic — EDRN Public Portal

Cancer.gov

The primary objective of the EDRN Pancreatic Cancer Working Group Proposal is to create a reference set consisting of well-characterized serum/plasma specimens to use as a resource for the development of biomarkers for the early detection of pancreatic adenocarcinoma. The testing of biomarkers on the same sample set permits direct comparison among them; thereby, allowing the development of a biomarker panel that can be evaluated in a future validation study. Additionally, the establishment of an infrastructure with core data elements and standardized operating procedures for specimen collection, processing and storage, will provide the necessary preparatory platform for larger validation studies when the appropriate marker/panel for pancreatic adenocarcinoma has been identified.

Cytology Specimen Management, Triage and Standardized Reporting of Fine Needle Aspiration Biopsies of the Pancreas

PubMed Central

Yoon, Won Jae; Bishop Pitman, Martha

2015-01-01

The recent advances in pancreas cytology specimen sampling methods have enabled a specific cytologic diagnosis in most cases. Proper triage and processing of the cytologic specimen is pivotal in making a diagnosis due to the need for ancillary testing in addition to cytological evaluation, which is especially true in the diagnosis of pancreatic cysts. Newly proposed terminology for pancreaticobiliary cytology offers a standardized language for reporting that aims to improve communication among patient caregivers and provide for increased flexibility in patient management. This review focuses on these updates in pancreas cytology for the optimal evaluation of solid and cystic lesions of the pancreas. PMID:26265683

Rapid, comprehensive, and affordable mycobacterial diagnosis with whole-genome sequencing: a prospective study

PubMed Central

Pankhurst, Louise J; del Ojo Elias, Carlos; Votintseva, Antonina A; Walker, Timothy M; Cole, Kevin; Davies, Jim; Fermont, Jilles M; Gascoyne-Binzi, Deborah M; Kohl, Thomas A; Kong, Clare; Lemaitre, Nadine; Niemann, Stefan; Paul, John; Rogers, Thomas R; Roycroft, Emma; Smith, E Grace; Supply, Philip; Tang, Patrick; Wilcox, Mark H; Wordsworth, Sarah; Wyllie, David; Xu, Li; Crook, Derrick W

2016-01-01

Summary Background Slow and cumbersome laboratory diagnostics for Mycobacterium tuberculosis complex (MTBC) risk delayed treatment and poor patient outcomes. Whole-genome sequencing (WGS) could potentially provide a rapid and comprehensive diagnostic solution. In this prospective study, we compare real-time WGS with routine MTBC diagnostic workflows. Methods We compared sequencing mycobacteria from all newly positive liquid cultures with routine laboratory diagnostic workflows across eight laboratories in Europe and North America for diagnostic accuracy, processing times, and cost between Sept 6, 2013, and April 14, 2014. We sequenced specimens once using local Illumina MiSeq platforms and processed data centrally using a semi-automated bioinformatics pipeline. We identified species or complex using gene presence or absence, predicted drug susceptibilities from resistance-conferring mutations identified from reference-mapped MTBC genomes, and calculated genetic distance to previously sequenced UK MTBC isolates to detect outbreaks. WGS data processing and analysis was done by staff masked to routine reference laboratory and clinical results. We also did a microcosting analysis to assess the financial viability of WGS-based diagnostics. Findings Compared with routine results, WGS predicted species with 93% (95% CI 90–96; 322 of 345 specimens; 356 mycobacteria specimens submitted) accuracy and drug susceptibility also with 93% (91–95; 628 of 672 specimens; 168 MTBC specimens identified) accuracy, with one sequencing attempt. WGS linked 15 (16% [95% CI 10–26]) of 91 UK patients to an outbreak. WGS diagnosed a case of multidrug-resistant tuberculosis before routine diagnosis was completed and discovered a new multidrug-resistant tuberculosis cluster. Full WGS diagnostics could be generated in a median of 9 days (IQR 6–10), a median of 21 days (IQR 14–32) faster than final reference laboratory reports were produced (median of 31 days [IQR 21–44]), at a cost of £481 per culture-positive specimen, whereas routine diagnosis costs £518, equating to a WGS-based diagnosis cost that is 7% cheaper annually than are present diagnostic workflows. Interpretation We have shown that WGS has a scalable, rapid turnaround, and is a financially feasible method for full MTBC diagnostics. Continued improvements to mycobacterial processing, bioinformatics, and analysis will improve the accuracy, speed, and scope of WGS-based diagnosis. Funding National Institute for Health Research, Department of Health, Wellcome Trust, British Colombia Centre for Disease Control Foundation for Population and Public Health, Department of Clinical Microbiology, Trinity College Dublin. PMID:26669893

Location specific solidification microstructure control in electron beam melting of Ti-6Al-4V

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narra, Sneha P.; Cunningham, Ross; Beuth, Jack

Relationships between prior beta grain size in solidified Ti-6Al-4V and melting process parameters in the Electron Beam Melting (EBM) process are investigated. Samples are built by varying a machine-dependent proprietary speed function to cover the process space. Optical microscopy is used to measure prior beta grain widths and assess the number of prior beta grains present in a melt pool in the raster region of the build. Despite the complicated evolution of beta grain sizes, the beta grain width scales with melt pool width. The resulting understanding of the relationship between primary machine variables and prior beta grain widths ismore » a key step toward enabling the location specific control of as-built microstructure in the EBM process. Control of grain width in separate specimens and within a single specimen is demonstrated.« less

Wear behavior of carbonitride-treated ploughshares produced from 30MnB5 steel for soil tillage applications

NASA Astrophysics Data System (ADS)

Yazici, A.

2011-09-01

The effects of gaseous carbonitriding processes on wear characteristics of 30MnB5 steel were investigated. The matrix of the carbonitride treated samples has a better wear resistance compared to the substrates of the conventionally heat-treated sample in laboratory conditions. The carbonitriding treatment condition giving rise to the lowest wear weight loss with the pin-on-disc wear machine was selected in order to harden ploughshare specimens to be tested in field experiments. The carbonitriding process at 860°C, with 0.9% C, and 0.6 m3/h NH3 for 105 min and quenched in 60°C oil followed by a 60 min tempering process at 140°C decreased 14.65% of total wear weight loss and 26.47% of total wear dimension loss of the ploughshare specimens in comparison to the conventional heat treatment process in field operational conditions.

Collection, transport and general processing of clinical specimens in Microbiology laboratory.

PubMed

Sánchez-Romero, M Isabel; García-Lechuz Moya, Juan Manuel; González López, Juan José; Orta Mira, Nieves

2018-02-06

The interpretation and the accuracy of the microbiological results still depend to a great extent on the quality of the samples and their processing within the Microbiology laboratory. The type of specimen, the appropriate time to obtain the sample, the way of sampling, the storage and transport are critical points in the diagnostic process. The availability of new laboratory techniques for unusual pathogens, makes necessary the review and update of all the steps involved in the processing of the samples. Nowadays, the laboratory automation and the availability of rapid techniques allow the precision and turn-around time necessary to help the clinicians in the decision making. In order to be efficient, it is very important to obtain clinical information to use the best diagnostic tools. Copyright © 2018 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

New taxonomy and old collections: integrating DNA barcoding into the collection curation process.

PubMed

Puillandre, N; Bouchet, P; Boisselier-Dubayle, M-C; Brisset, J; Buge, B; Castelin, M; Chagnoux, S; Christophe, T; Corbari, L; Lambourdière, J; Lozouet, P; Marani, G; Rivasseau, A; Silva, N; Terryn, Y; Tillier, S; Utge, J; Samadi, S

2012-05-01

Because they house large biodiversity collections and are also research centres with sequencing facilities, natural history museums are well placed to develop DNA barcoding best practices. The main difficulty is generally the vouchering system: it must ensure that all data produced remain attached to the corresponding specimen, from the field to publication in articles and online databases. The Museum National d'Histoire Naturelle in Paris is one of the leading laboratories in the Marine Barcode of Life (MarBOL) project, which was used as a pilot programme to include barcode collections for marine molluscs and crustaceans. The system is based on two relational databases. The first one classically records the data (locality and identification) attached to the specimens. In the second one, tissue-clippings, DNA extractions (both preserved in 2D barcode tubes) and PCR data (including primers) are linked to the corresponding specimen. All the steps of the process [sampling event, specimen identification, molecular processing, data submission to Barcode Of Life Database (BOLD) and GenBank] are thus linked together. Furthermore, we have developed several web-based tools to automatically upload data into the system, control the quality of the sequences produced and facilitate the submission to online databases. This work is the result of a joint effort from several teams in the Museum National d'Histoire Naturelle (MNHN), but also from a collaborative network of taxonomists and molecular systematists outside the museum, resulting in the vouchering so far of ∼41,000 sequences and the production of ∼11,000 COI sequences. © 2012 Blackwell Publishing Ltd.

Behavior of an MBT waste in monotonic triaxial shear tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhandari, Athma Ram, E-mail: athma.bhandari@beg.utexas.edu; Powrie, William, E-mail: w.powrie@soton.ac.uk

2013-04-15

Highlights: ► We studied the stress–strain–strength characteristics of an MBT waste. ► Rate of mobilization of strength with strain depends on initial density. ► Image analysis technique was used to determine whole-specimen displacement fields. ► Initial mode of deformation of a loose specimen is one-dimensional compression. ► Reinforcing elements enhance the resistance to lateral and volumetric deformation. - Abstract: Legislation in some parts of the world now requires municipal solid waste (MSW) to be processed prior to landfilling to reduce its biodegradability and hence its polluting potential through leachate and fugitive emission of greenhouse gases. This pre-processing may be achievedmore » through what is generically termed mechanical–biological-treatment (MBT). One of the major concerns relating to MBT wastes is that the strength of the material may be less than for raw MSW, owing to the removal of sheet, stick and string-like reinforcing elements during processing. Also, the gradual increase in mobilized strength over strains of 30% or so commonly associated with unprocessed municipal solid waste may not occur with treated wastes. This paper describes a series of triaxial tests carried out to investigate the stress–strain–strength characteristics of an MBT waste, using a novel digital image analysis technique for the determination of detailed displacement fields over the whole specimen. New insights gained into the mechanical behavior of MBT waste include the effect of density on the stress–strain response, the initial 1-D compression of lightly consolidated specimens, and the likely reinforcing effect of small sheet like particles remaining in the waste.« less

Surface conductance of graphene from non-contact resonant cavity.

PubMed

Obrzut, Jan; Emiroglu, Caglar; Kirillov, Oleg; Yang, Yanfei; Elmquist, Randolph E

2016-06-01

A method is established to reliably determine surface conductance of single-layer or multi-layer atomically thin nano-carbon graphene structures. The measurements are made in an air filled standard R100 rectangular waveguide configuration at one of the resonant frequency modes, typically at TE 103 mode of 7.4543 GHz. Surface conductance measurement involves monitoring a change in the quality factor of the cavity as the specimen is progressively inserted into the cavity in quantitative correlation with the specimen surface area. The specimen consists of a nano-carbon-layer supported on a low loss dielectric substrate. The thickness of the conducting nano-carbon layer does not need to be explicitly known, but it is assumed that the lateral dimension is uniform over the specimen area. The non-contact surface conductance measurements are illustrated for a typical graphene grown by chemical vapor deposition process, and for a high quality monolayer epitaxial graphene grown on silicon carbide wafers for which we performed non-gated quantum Hall resistance measurements. The sequence of quantized transverse Hall resistance at the Landau filling factors ν = ±6 and ±2, and the absence of the Hall plateau at ν = 4 indicate that the epitaxially grown graphene is a high quality mono-layer. The resonant microwave cavity measurement is sensitive to the surface and bulk conductivity, and since no additional processing is required, it preserves the integrity of the conductive graphene layer. It allows characterization with high speed, precision and efficiency, compared to transport measurements where sample contacts must be defined and applied in multiple processing steps.

Fatigue Behavior of Porous Ti-6Al-4V Made by Laser-Engineered Net Shaping

PubMed Central

Bordonaro, Giancarlo G.; Berto, Filippo

2018-01-01

The fatigue behavior and fracture mechanisms of additively manufactured Ti-6Al-4V specimens are investigated in this study. Three sets of testing samples were fabricated for the assessment of fatigue life. The first batch of samples was built by using Laser-Engineered Net Shaping (LENS) technology, a Direct Energy Deposition (DED) method. Internal voids and defects were induced in a second batch of samples by changing LENS machine processing parameters. Fatigue performance of these samples is compared to the wrought Ti-6Al-4V samples. The effects of machine-induced porosity are assessed on mechanical properties and results are presented in the form of SN curves for the three sets of samples. Fracture mechanisms are examined by using Scanning Electron Microscopy (SEM) to characterize the morphological characteristics of the failure surface. Different fracture surface morphologies are observed for porous and non-porous specimens due to the combination of head write speed and laser power. Formation of defects such as pores, unmelted regions, and gas entrapments affect the failure mechanisms in porous specimens. Non-porous specimens exhibit fatigue properties comparable with that of the wrought specimens, but porous specimens are found to show a tremendous reduced fatigue strength. PMID:29439510

External quality assurance in nongynecologic cytology: The Australasian experience.

PubMed

Shield, Paul W; Frost, Felicity; Finnimore, Jo L; Wright, R Gordon; Cummings, Margaret C

2017-05-01

The Royal College of Pathologists of Australasia Cytopathology Quality Assurance Program has operated an external quality assurance program in nongynecologic cytopathology since 1993. Glass slide preparations of a wide range of nongynecologic cases were circulated to approximately 200 cytopathology laboratories in 16 countries. General nongynecologic cytology cases were manufactured from residual specimens after routine diagnosis. Fine-needle aspiration (FNA) cases were made by sampling fresh tissue and making direct specimens. The majority of cases consisted of both air-dried and fixed preparations. Results returned to laboratories included illustrated case discussions highlighting diagnostic features, key differential diagnoses, and useful adjunctive tests. The current study reviewed >22,000 results for 123 nongynecologic cases. Cases found to cause the most diagnostic difficulties included serous effusion cases with metastatic carcinoma in a dispersed pattern, well-differentiated carcinoma, and cellular reactive cases; urine specimens with sparse malignant cells; reactive pneumocytes in a bronchoalveolar lavage; breast FNA cases with papillary lesions; gestational specimens; and fibroadenoma. FNA specimens from the lung and thyroid, particularly papillary thyroid carcinoma, generally were well reported. The use of multiple preparations of the same specimen has allowed interlaboratory comparison, and the quality assurance program has played an educational role as well as informing the laboratory accreditation process. Cancer Cytopathol 2017;125:349-361. © 2017 American Cancer Society. © 2017 American Cancer Society.

Thin-layer preparations of dithiothreitol-treated bronchial washing specimens.

PubMed

Koivurinne, Kirsti I; Shield, Paul W

2003-01-01

To evaluate the combined effect of dithiothreitol (DTT) treatment and ThinPrep (TP) (Cytyc Corp, Boxborough, Massachusetts, U.S.A.) processing on bronchial washing specimens. A total of 431 bronchial washing specimens were initially treated with 0.05% DTT in a 30% methanol solution. After centrifugation, 1 TP slide and 2-4 conventional cytospin or smear preparations (CPs) were prepared. The reports of both preparations were compared in all cases. All 48 abnormal cases and 52 consecutive negative cases were also compared for cellular composition, distribution of the cells, ease of interpretation and overall preparation quality. Screening time was recorded for 20 of the cases. The diagnostic accuracy of one TP slide appeared comparable to that of 2-4 CPs. The TP slide was assessed to be equal or superior in overall quality to CP in 85% of 100 cases of paired specimens. The cleaner background and smaller cellular area of TP slides significantly reduced the screening time. Mucolysis and specimen homogenization were not always optimal, occasionally resulting in uneven subsampling and poorly cellular TPs. However, in general, TP slides were considered superior to CPs in overall quality. Improvement in specimen quality and reduced screening time have to be balanced against the high cost of consumables with the TP technique.

Novel infrastructure for sepsis biomarker research in critically ill neonates and children.

PubMed

Juskewitch, Justin E; Enders, Felicity T; Abraham, Roshini S; Huskins, W Charles

2013-02-01

Sepsis biomarker research requires an infrastructure to identify septic patients efficiently and to collect and store specimens properly. We developed a novel infrastructure to study biomarkers of sepsis in children. Patients in pediatric and neonatal intensive care units were enrolled prospectively; enrollment information was stored in a secure, remotely accessible database. Researchers were notified of electronic medical record (EMR) orders for blood cultures (a surrogate for a diagnostic evaluation of suspected sepsis) by a page triggered by the order. Staff confirmed patient enrollment and remotely submitted an EMR order for collection of study specimens simultaneous with the blood culture. Specimens were processed and stored by a mobile clinical research unit. Over 2 years, 2029 patients were admitted; 138 were enrolled. Staff received pages for 95% of blood cultures collected from enrolled patients. The median time between the blood culture order and collection was 34 minutes (range 9-241). Study specimens were collected simultaneously with 41 blood cultures. The median times between specimen collection and storage for flow cytometry and cytokine analysis were 33 minutes (range 0-82) and 52 minutes (range 28-98), respectively. This novel infrastructure facilitated prompt, proper collection and storage of specimens for sepsis biomarker analysis. © 2013 Wiley Periodicals, Inc.

Study of corrosion-related defects of zirconium alloys with slow positron beam

NASA Astrophysics Data System (ADS)

Zhu, Zhejie; Yao, Meiyi; Shi, Jianjian; Yao, Chunlong; Lu, Eryang; Cao, Xingzhong; Wang, Baoyi; Wu, Yichu

2018-09-01

The corrosion behavior of Zr-4 and N5 alloy specimens corroded in 0.01 mol/L LiOH aqueous solution at 360 °C/18.6 MPa and in super heated steam at 400 °C/10.3 MPa for 1, 3 and 14 days were investigated by slow positron beam based Doppler broadening spectroscopy. Results showed that there was an evident interfacial layer with pre-existed vacancies and voids in uncorroded Zr-4 specimens, while in uncorroded N5 specimen, the interfacial defect layer can not be identified or a thin interfacial layer was only contained. When the specimens were corroded in super heated steam at 400 °C/10.3 MPa for a few days, the existence of the interface layer in the Zr-4 specimen would delay the diffusion rate of the oxygen atoms and decelerated the oxidation rate of the corrosion process. However, at very early stage of the corrosion, as Zr-4 and N5 specimens were corrded in 0.01 mol/L LiOH aqueous solution at 360 °C/18.6 MPa, the effect of Li+ accelerated the diffusion rate of the oxygen atoms, while the effect of the interface defect layer became a minor effect.

Content-based analysis of Ki-67 stained meningioma specimens for automatic hot-spot selection.

PubMed

Swiderska-Chadaj, Zaneta; Markiewicz, Tomasz; Grala, Bartlomiej; Lorent, Malgorzata

2016-10-07

Hot-spot based examination of immunohistochemically stained histological specimens is one of the most important procedures in pathomorphological practice. The development of image acquisition equipment and computational units allows for the automation of this process. Moreover, a lot of possible technical problems occur in everyday histological material, which increases the complexity of the problem. Thus, a full context-based analysis of histological specimens is also needed in the quantification of immunohistochemically stained specimens. One of the most important reactions is the Ki-67 proliferation marker in meningiomas, the most frequent intracranial tumour. The aim of our study is to propose a context-based analysis of Ki-67 stained specimens of meningiomas for automatic selection of hot-spots. The proposed solution is based on textural analysis, mathematical morphology, feature ranking and classification, as well as on the proposed hot-spot gradual extinction algorithm to allow for the proper detection of a set of hot-spot fields. The designed whole slide image processing scheme eliminates such artifacts as hemorrhages, folds or stained vessels from the region of interest. To validate automatic results, a set of 104 meningioma specimens were selected and twenty hot-spots inside them were identified independently by two experts. The Spearman rho correlation coefficient was used to compare the results which were also analyzed with the help of a Bland-Altman plot. The results show that most of the cases (84) were automatically examined properly with two fields of view with a technical problem at the very most. Next, 13 had three such fields, and only seven specimens did not meet the requirement for the automatic examination. Generally, the Automatic System identifies hot-spot areas, especially their maximum points, better. Analysis of the results confirms the very high concordance between an automatic Ki-67 examination and the expert's results, with a Spearman rho higher than 0.95. The proposed hot-spot selection algorithm with an extended context-based analysis of whole slide images and hot-spot gradual extinction algorithm provides an efficient tool for simulation of a manual examination. The presented results have confirmed that the automatic examination of Ki-67 in meningiomas could be introduced in the near future.

Variability in, variability out: best practice recommendations to standardize pre-analytical variables in the detection of circulating and tissue microRNAs.

PubMed

Khan, Jenna; Lieberman, Joshua A; Lockwood, Christina M

2017-05-01

microRNAs (miRNAs) hold promise as biomarkers for a variety of disease processes and for determining cell differentiation. These short RNA species are robust, survive harsh treatment and storage conditions and may be extracted from blood and tissue. Pre-analytical variables are critical confounders in the analysis of miRNAs: we elucidate these and identify best practices for minimizing sample variation in blood and tissue specimens. Pre-analytical variables addressed include patient-intrinsic variation, time and temperature from sample collection to storage or processing, processing methods, contamination by cells and blood components, RNA extraction method, normalization, and storage time/conditions. For circulating miRNAs, hemolysis and blood cell contamination significantly affect profiles; samples should be processed within 2 h of collection; ethylene diamine tetraacetic acid (EDTA) is preferred while heparin should be avoided; samples should be "double spun" or filtered; room temperature or 4 °C storage for up to 24 h is preferred; miRNAs are stable for at least 1 year at -20 °C or -80 °C. For tissue-based analysis, warm ischemic time should be <1 h; cold ischemic time (4 °C) <24 h; common fixative used for all specimens; formalin fix up to 72 h prior to processing; enrich for cells of interest; validate candidate biomarkers with in situ visualization. Most importantly, all specimen types should have standard and common workflows with careful documentation of relevant pre-analytical variables.

Electromechanical Apparatus Measures Residual Stress

NASA Technical Reports Server (NTRS)

Chern, Engmin J.; Flom, Yury

1993-01-01

Nondestructive test exploits relationship between stress and eddy-current-probe resistance. Yields data on residual stress or strain in metal tension/compression specimen (stress or strain remaining in specimen when no stress applied from without). Apparatus is assembly of commercial equipment: tension-or-compression testing machine, eddy-current probe, impedance gain-and-phase analyzer measuring impedance of probe coil, and desktop computer, which controls other equipment and processes data received from impedance gain-and-phase analyzer.

Processing Research on Chemically Vapor Deposited Silicon Nitride.

DTIC Science & Technology

1979-12-01

34 sea urchins ") predominated, suggesting that formation was primarily from the vapor phase with little of the nodular growths seen at only slightly...Specimen HW-4-200-10 .................................. 3-38 3-17 Fracture Stress: Grain Size Correlation 3-39 3-18 SEM Fractographs of Flexure...4-202-10 ........ 3-42 3-21 SEM Fractographs of Flexure Specimen HW-4-200-4 ......... 3-43 3-22 SEM Fractographs of Compression Side of Flexure

[Research status and prospects of DNA test on difficult specimens].

PubMed

Dang, Hua-Wei; Mao, Jiong; Wang, Hui; Huang, Jiang-Ping; Bai, Xiao-Gang

2012-02-01

This paper reviews the advances of DNA detection on three types of difficult biological specimens including degraded samples, trace evidences and mixed samples. The source of different samples, processing methods and announcements were analyzed. New methods such as mitochondrial test system, changing the original experimental conditions, low-volume PCR amplification and new technologies such as whole genome amplification techniques, laser capture micro-dissection, and mini-STR technology in recent years are introduced.

Technical note: Discard the specimen collection swab directly at point of care to improve extensive automated processing in clinical microbiology laboratories.

PubMed

Avolio, Manuela; Grosso, Shamanta; Bruschetta, Graziano; Camporese, Alessandro

2016-10-01

We compared, in terms of microorganisms recovery, the discard of specimen collection swab, after swirling into its medium, directly at point of care, with its placing into the medium and vortexing on arrival in the laboratory. Our results show that these two procedures are overlapped in terms of bacterial recovery. Copyright © 2016 Elsevier B.V. All rights reserved.

Issues in collecting, processing and storing human tissues and associated information to support biomedical research.

PubMed

Grizzle, William E; Bell, Walter C; Sexton, Katherine C

2010-01-01

The availability of human tissues to support biomedical research is critical to advance translational research focused on identifying and characterizing approaches to individualized (personalized) medical care. Providing such tissues relies on three acceptable models - a tissue banking model, a prospective collection model and a combination of these two models. An unacceptable model is the "catch as catch can" model in which tissues are collected, processed and stored without goals or a plan or without standard operating procedures, i.e., portions of tissues are collected as available and processed and stored when time permits. In the tissue banking model, aliquots of tissues are collected according to SOPs. Usually specific sizes and types of tissues are collected and processed (e.g., 0.1 gm of breast cancer frozen in OCT). Using the banking model, tissues may be collected that may not be used and/or do not meet specific needs of investigators; however, at the time of an investigator request, tissues are readily available as is clinical information including clinical outcomes. In the model of prospective collection, tissues are collected based upon investigator requests including specific requirements of investigators. For example, the investigator may request that two 0.15 gm matching aliquots of breast cancer be minced while fresh, put in RPMI media with and without fetal calf serum, cooled to 4°C and shipped to the investigator on wet ice. Thus, the tissues collected prospectively meet investigator needs, all collected specimens are utilized and storage of specimens is minimized; however, investigators must wait until specimens are collected, and if needed, for clinical outcome. The operation of any tissue repository requires well trained and dedicated personnel. A quality assurance program is required which provides quality control information on the diagnosis of a specimen that is matched specifically to the specimen provided to an investigator instead of an overall diagnosis of the specimen via a surgical pathology report. This is necessary because a specific specimen may not match the diagnosis of the case due to many factors such as necrosis, unsuspected tumor invasion of apparently normal tissue, and areas of fibrosis which are mistaken grossly for tumor. Aliquots for quality control (QC) may or may not be collected at the time of collection and in some cases, QC may not occur until specimens are distributed to investigators. In establishing a tumor repository, multiple issues need to be considered. These include the available resources, long term support, space and equipment. The needs of the potential users need to be identified as to the types of tissues and services needed and the annotation expected. Other specific issues to be considered include collection of specimens potentially infected with blood borne pathogens (e.g., hepatitis B), charge back mechanisms, informatics needs and support, and investigator requirements (e.g., recognition of repository contributions in publications). In general, the repository should not perform the research of the investigators, but should provide the infrastructure necessary to support the research of the investigator. Thus, the goals of the repository must be established. Similarly, ethical and regulatory issues must be evaluated. In general, tissue repositories need ethical (e.g., IRB) and privacy (e.g., HIPAA) review. Also, safety issues need to be considered as well as how biohazards will be addressed by investigator-users. Considerations involving the transfer of specimens to other organization usually require a material transfer agreement (MTA). A MTA should address biohazards as well as indemnification. Thus, many issues must be considered and addressed in order to establish and operate successfully a biorepository.

Maintaining respect and fairness in the usage of stored shared specimens

PubMed Central

2013-01-01

Background Every year, research specimens are shipped from one institution to another as well as across national boundaries. A significant proportion of specimens move from poor to rich countries. Concerns are always raised on the future usage of the stored specimens shipped to research insitutions from developing countries. Creating awareness of the processes is required in all sectors involved in biomedical research. To maintain fairness and respect in sharing biomedical specimens and reserch products requires safeguarding by Ethics Review Committees in both provider and recepient institutions. Training in basic ethical principles in research is required to all sectors involved in biomedical research so as to level up the research playing field. Discussion By agreeing to provide specimens, individuals and communities from whom samples are collected would have placed their trust and all ensuing up-keep of the specimens to the researchers. In most collaborative set-up, laid down material transfer agreements are negotiated and signed before the shipment of specimens. Researchers, research ethics committees (RECs) and institutions in the countries of origin are supposed to serve as overseers of the specimens. There is need to advocate for honesty in sample handling and sharing, and also need to oversee any written commitments by researchers, RECs and institutions at source as well as in recipient institution. Commitments from source RECs and Institutional Review Boards (IRBs) and in the receiving institution on overseeing the future usage of stored specimens are required; including the ultimate confirmation abiding by the agreement. Training in ethical issues pertaining to sample handling and biomedical research in general is essential at all levels of academic pursuit. While sharing of biological specimens and research data demands honesty and oversight by ethical regulatory agents from both institutions in developing country and recepient institutions in developed countries. Concluding summary Archiving of biological specimens requires reconsideration for the future of biomedical findings and scientific break-throughs. Biomedical ethical regulations still need to established clear viable regulations that have vision for the future of science through shared and archived samples. This discussion covers and proposes essential points that need to be considered in view of future generations and scientific break-throughs. The discussion is based on the experience of working in resource-limited settings, the local regulatory laws and the need to refine research regulations governing sharing and storage of specimens for the future of science. PMID:24565022

Maintaining respect and fairness in the usage of stored shared specimens.

PubMed

Mduluza, Takafira; Midzi, Nicholas; Duruza, Donold; Ndebele, Paul

2013-01-01

Every year, research specimens are shipped from one institution to another as well as across national boundaries. A significant proportion of specimens move from poor to rich countries. Concerns are always raised on the future usage of the stored specimens shipped to research institutions from developing countries. Creating awareness of the processes is required in all sectors involved in biomedical research. To maintain fairness and respect in sharing biomedical specimens and research products requires safeguarding by Ethics Review Committees in both provider and recipient institutions. Training in basic ethical principles in research is required to all sectors involved in biomedical research so as to level up the research playing field. By agreeing to provide specimens, individuals and communities from whom samples are collected would have placed their trust and all ensuing up-keep of the specimens to the researchers. In most collaborative set-up, laid down material transfer agreements are negotiated and signed before the shipment of specimens. Researchers, research ethics committees (RECs) and institutions in the countries of origin are supposed to serve as overseers of the specimens. There is need to advocate for honesty in sample handling and sharing, and also need to oversee any written commitments by researchers, RECs and institutions at source as well as in recipient institution. Commitments from source RECs and Institutional Review Boards (IRBs) and in the receiving institution on overseeing the future usage of stored specimens are required; including the ultimate confirmation abiding by the agreement. Training in ethical issues pertaining to sample handling and biomedical research in general is essential at all levels of academic pursuit. While sharing of biological specimens and research data demands honesty and oversight by ethical regulatory agents from both institutions in developing country and recipient institutions in developed countries. Archiving of biological specimens requires reconsideration for the future of biomedical findings and scientific break-throughs. Biomedical ethical regulations still need to established clear viable regulations that have vision for the future of science through shared and archived samples. This discussion covers and proposes essential points that need to be considered in view of future generations and scientific break-throughs. The discussion is based on the experience of working in resource-limited settings, the local regulatory laws and the need to refine research regulations governing sharing and storage of specimens for the future of science.

Effect of Thermal History on Microstructures and Mechanical Properties of AZ31 Magnesium Alloy Prepared by Friction Stir Processing

PubMed Central

Chai, Fang; Zhang, Datong; Li, Yuanyuan

2014-01-01

Hot-rolled AZ31 (Mg-2.57Al-0.84Zn-0.32Mn, in mass percentage) magnesium alloy is subjected to friction stir processing in air (normal friction stir processing, NFSP) and under water (submerged friction stir processing, SFSP). Thermal history of the two FSP procedures is measured, and its effect on microstructures and mechanical properties of the experimental materials is investigated. Compared with NFSP, the peak temperature during SFSP is lower and the duration time at a high temperature is shorter due to the enhanced cooling effect of water. Consequently, SFSP results in further grain refinement, and the average grain size of the NFSP and SFSP specimens in the stir zone (SZ) are 2.9 μm and 1.3 μm, respectively. Transmission electron microscopy (TEM) examinations confirm that grain refinement is attributed to continuous dynamic recrystallization both for NFSP and SFSP. The average Vickers hardness in the SZ of the NFSP and SFSP AZ31 magnesium alloy are 76 HV and 87 HV. Furthermore, the ultimate tensile strength and the elongation of the SFSP specimen increase from 191 MPa and 31.3% in the NFSP specimen to 210 MPa and 50.5%, respectively. Both the NFSP and SFSP alloys fail through ductile fracture, but the dimples are much more obvious in the SFSP alloy. PMID:28788532

Evaluation of a New Automated Processing System (TACAS™ Pro) for Liquid-Based Procedures.

PubMed

Kuramoto, Hiroyuki; Sugimoto, Naoko; Iwami, Yoshiko; Kato, Chizuyo; Hori, Masuko; Iida, Manichi

2015-01-01

To evaluate a fully automated processing system (TACAS™ Pro) for liquid-based procedures (LBPs). Materials were 3,483 and additionally 502 specimens that were taken at Kanagawa Health Service Association. Specimens obtained with a Cervex-Brush® were first smeared to glass slides using one side of the brush and then processed to TACAS Pro. (1) The microscopy watching time per normal case was 3.65 ± 0.85 min in the conventional procedure, whereas in the LBP it was 1.95 ± 0.60 min, and the latter reduced workload to 53%. (2) The handling time of TACAS Pro per day was 2 h and 25.8 min. The workload at a laboratory offset it and revealed the work saving to be 63.8%. (3) Unsatisfactory rates were 0% in the conventional procedure, whereas in the LBP it was 1.88% at first. The latter rate decreased to 0.5% after system improvement. (4) Specimens which may disturb microscopy analysis were found in 1.06%, including 3 cases of possible carry-over of cells to the following slides. An additional study with the revised system confirmed no carry-over. (5) Incidences of abnormal cytology were consistent between the two methods. The revised automated processing system TACAS Pro is a feasible and useful LBP and reduces the workload of cytology laboratories. © 2015 S. Karger AG, Basel.

49 CFR 40.73 - How is the collection process completed?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false How is the collection process completed? 40.73 Section 40.73 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Specimen Collections § 40.73 How is the collection process...

49 CFR 40.73 - How is the collection process completed?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false How is the collection process completed? 40.73 Section 40.73 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Specimen Collections § 40.73 How is the collection process...

49 CFR 40.73 - How is the collection process completed?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 1 2012-10-01 2012-10-01 false How is the collection process completed? 40.73 Section 40.73 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Specimen Collections § 40.73 How is the collection process...

49 CFR 40.73 - How is the collection process completed?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 1 2014-10-01 2014-10-01 false How is the collection process completed? 40.73 Section 40.73 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Specimen Collections § 40.73 How is the collection process...

Assessment of breast pathologies using nonlinear microscopy

PubMed Central

Tao, Yuankai K.; Shen, Dejun; Sheikine, Yuri; Ahsen, Osman O.; Wang, Helen H.; Schmolze, Daniel B.; Johnson, Nicole B.; Brooker, Jeffrey S.; Cable, Alex E.; Connolly, James L.; Fujimoto, James G.

2014-01-01

Rapid intraoperative assessment of breast excision specimens is clinically important because up to 40% of patients undergoing breast-conserving cancer surgery require reexcision for positive or close margins. We demonstrate nonlinear microscopy (NLM) for the assessment of benign and malignant breast pathologies in fresh surgical specimens. A total of 179 specimens from 50 patients was imaged with NLM using rapid extrinsic nuclear staining with acridine orange and intrinsic second harmonic contrast generation from collagen. Imaging was performed on fresh, intact specimens without the need for fixation, embedding, and sectioning required for conventional histopathology. A visualization method to aid pathological interpretation is presented that maps NLM contrast from two-photon fluorescence and second harmonic signals to features closely resembling histopathology using hematoxylin and eosin staining. Mosaicking is used to overcome trade-offs between resolution and field of view, enabling imaging of subcellular features over square-centimeter specimens. After NLM examination, specimens were processed for standard paraffin-embedded histology using a protocol that coregistered histological sections to NLM images for paired assessment. Blinded NLM reading by three pathologists achieved 95.4% sensitivity and 93.3% specificity, compared with paraffin-embedded histology, for identifying invasive cancer and ductal carcinoma in situ versus benign breast tissue. Interobserver agreement was κ = 0.88 for NLM and κ = 0.89 for histology. These results show that NLM achieves high diagnostic accuracy, can be rapidly performed on unfixed specimens, and is a promising method for intraoperative margin assessment. PMID:25313045

The AIDS and Cancer Specimen Resource: Role in HIV/AIDS scientific discovery

PubMed Central

Ayers, Leona W; Silver, Sylvia; McGrath, Michael S; Orenstein, Jan M

2007-01-01

The AIDS Cancer and Specimen Resource (ACSR) supports scientific discovery in the area of HIV/AIDS-associated malignancies. The ACSR was established as a cooperative agreement between the NCI (Office of the Director, Division of Cancer Treatment and Diagnosis) and regional consortia, University of California, San Francisco (West Coast), George Washington University (East Coast) and Ohio State University (Mid-Region) to collect, preserve and disperse HIV-related tissues and biologic fluids and controls along with clinical data to qualified investigators. The available biological samples with clinical data and the application process are described on the ACSR web site. The ACSR tissue bank has more than 100,000 human HIV positive specimens that represent different processing (43), specimen (15), and anatomical site (50) types. The ACSR provides special biospecimen collections and prepares speciality items, e.g., tissue microarrays (TMA), DNA libraries. Requests have been greatest for Kaposi's sarcoma (32%) and non-Hodgkin's lymphoma (26%). Dispersed requests include 83% tissue (frozen and paraffin embedded), 18% plasma/serum and 9% other. ACSR also provides tissue microarrays of, e.g., Kaposi's sarcoma and non-Hodgkin's lymphoma, for biomarker assays and has developed collaborations with other groups that provide access to additional AIDS-related malignancy specimens. ACSR members and associates have completed 63 podium and poster presentations. Investigators have submitted 125 letters of intent requests. Discoveries using ACSR have been reported in 61 scientific publications in notable journals with an average impact factor of 7. The ACSR promotes the scientific exploration of the relationship between HIV/AIDS and malignancy by participation at national and international scientific meetings, contact with investigators who have productive research in this area and identifying, collecting, preserving, enhancing, and dispersing HIV/AIDS-related malignancy specimens to funded, approved researchers at no fee. Scientific discovery has been advanced by this unique biorepository. Investigators are encouraged to browse the ACSR Internet site for materials to enhance their own scientific initiatives. PMID:17335575

Sequencing degraded DNA from non-destructively sampled museum specimens for RAD-tagging and low-coverage shotgun phylogenetics.

PubMed

Tin, Mandy Man-Ying; Economo, Evan Philip; Mikheyev, Alexander Sergeyevich

2014-01-01

Ancient and archival DNA samples are valuable resources for the study of diverse historical processes. In particular, museum specimens provide access to biotas distant in time and space, and can provide insights into ecological and evolutionary changes over time. However, archival specimens are difficult to handle; they are often fragile and irreplaceable, and typically contain only short segments of denatured DNA. Here we present a set of tools for processing such samples for state-of-the-art genetic analysis. First, we report a protocol for minimally destructive DNA extraction of insect museum specimens, which produced sequenceable DNA from all of the samples assayed. The 11 specimens analyzed had fragmented DNA, rarely exceeding 100 bp in length, and could not be amplified by conventional PCR targeting the mitochondrial cytochrome oxidase I gene. Our approach made these samples amenable to analysis with commonly used next-generation sequencing-based molecular analytic tools, including RAD-tagging and shotgun genome re-sequencing. First, we used museum ant specimens from three species, each with its own reference genome, for RAD-tag mapping. Were able to use the degraded DNA sequences, which were sequenced in full, to identify duplicate reads and filter them prior to base calling. Second, we re-sequenced six Hawaiian Drosophila species, with millions of years of divergence, but with only a single available reference genome. Despite a shallow coverage of 0.37 ± 0.42 per base, we could recover a sufficient number of overlapping SNPs to fully resolve the species tree, which was consistent with earlier karyotypic studies, and previous molecular studies, at least in the regions of the tree that these studies could resolve. Although developed for use with degraded DNA, all of these techniques are readily applicable to more recent tissue, and are suitable for liquid handling automation.

Osteology of a new specimen of Macrocnemus aff. M. fuyuanensis (Archosauromorpha, Protorosauria) from the Middle Triassic of Europe: potential implications for species recognition and paleogeography of tanystropheid protorosaurs

NASA Astrophysics Data System (ADS)

Jaquier, Vivien P.; Fraser, Nicholas C.; Furrer, Heinz; Scheyer, Torsten M.

2017-11-01

Over the past two decades, a wealth of marine and terrestrial reptiles, including protorosaurian archosauromorphs, has been described from Triassic shales and limestone layers in southern China. Recovered from the eastern margin of the Tethys Ocean, these forms often show remarkable similarities to taxa that were previously known and described from Europe, i.e., the western Tethyan margin. One protorosaurian that is known from the western and the eastern Tethyan province is the genus Macrocnemus, with currently three recognized species: 1) M. bassanii from the Middle Triassic Besano Formation and Meride Limestone (late Anisian – early Ladinian), UNESCO World Heritage Site Monte San Giorgio, Ticino, Switzerland; 2) M. obristi from the Prosanto Formation (early Ladinian) of the Ducan area, Grisons, Switzerland; and 3) M. fuyuanensis from the Falang Formation (Ladinian), Yunnan Province, southern China. Recently a new specimen, PIMUZ T 1559, from the upper Besano Formation at Meride, Ticino, Switzerland, was prepared, revealing a disarticulated skeleton which includes most of the cranium and lower jaw, pre-caudal vertebral column and ribs, the forelimbs, and girdle elements. Unambiguously assignable to the genus Macrocnemus, it evinces particularly gracile elongated cervical ribs, as well as a humerus/radius ratio that is comparable only to that of M. fuyuanensis from southern China. Based on this feature we tentatively recognize the new specimen as M. aff. fuyuanensis from Europe. The position and exquisite preservation of the clavicle and interclavicle in this specimen allows a revision of the shoulder girdle of Macrocnemus when articulated, which also has implications for closely related protorosaurian taxa, such as the long-necked Tanystropheus. Furthermore, differences in the shape and morphology of the interclavicle including pointed wing-like lateral processes and a short, fusiform caudal process represent rare discrete characters that allow separation of the specimens of M. bassanii from the new specimen of M. aff. fuyuanensis.

Characterization of the Fe-Co-1.5V soft ferromagnetic alloy processed by Laser Engineered Net Shaping (LENS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kustas, Andrew B.; Susan, Donald F.; Johnson, Kyle L.

Processing of the low workability Fe-Co-1.5V (Hiperco® equivalent) alloy is demonstrated using the Laser Engineered Net Shaping (LENS) metals additive manufacturing technique. As an innovative and highly localized solidification process, LENS is shown to overcome workability issues that arise during conventional thermomechanical processing, enabling the production of bulk, near net-shape forms of the Fe-Co alloy. Bulk LENS structures appeared to be ductile with no significant macroscopic defects. Atomic ordering was evaluated and significantly reduced in as-built LENS specimens relative to an annealed condition, tailorable through selection of processing parameters. Fine equiaxed grain structures were observed in as-built specimens following solidification,more » which then evolved toward a highly heterogeneous bimodal grain structure after annealing. The microstructure evolution in Fe-Co is discussed in the context of classical solidification theory and selective grain boundary pinning processes. In conclusion, magnetic properties were also assessed and shown to fall within the extremes of conventionally processed Hiperco® alloys.« less

Characterization of the Fe-Co-1.5V soft ferromagnetic alloy processed by Laser Engineered Net Shaping (LENS)

DOE PAGES

Kustas, Andrew B.; Susan, Donald F.; Johnson, Kyle L.; ...

2018-02-21

Processing of the low workability Fe-Co-1.5V (Hiperco® equivalent) alloy is demonstrated using the Laser Engineered Net Shaping (LENS) metals additive manufacturing technique. As an innovative and highly localized solidification process, LENS is shown to overcome workability issues that arise during conventional thermomechanical processing, enabling the production of bulk, near net-shape forms of the Fe-Co alloy. Bulk LENS structures appeared to be ductile with no significant macroscopic defects. Atomic ordering was evaluated and significantly reduced in as-built LENS specimens relative to an annealed condition, tailorable through selection of processing parameters. Fine equiaxed grain structures were observed in as-built specimens following solidification,more » which then evolved toward a highly heterogeneous bimodal grain structure after annealing. The microstructure evolution in Fe-Co is discussed in the context of classical solidification theory and selective grain boundary pinning processes. In conclusion, magnetic properties were also assessed and shown to fall within the extremes of conventionally processed Hiperco® alloys.« less

A Study on the Influence of Process Parameters on the Viscoelastic Properties of ABS Components Manufactured by FDM Process

NASA Astrophysics Data System (ADS)

Dakshinamurthy, Devika; Gupta, Srinivasa

2018-04-01

Fused Deposition Modelling (FDM) is a fast growing Rapid Prototyping (RP) technology due to its ability to build parts having complex geometrical shape in reasonable time period. The quality of built parts depends on many process variables. In this study, the influence of three FDM process parameters namely, slice height, raster angle and raster width on viscoelastic properties of Acrylonitrile Butadiene Styrene (ABS) RP-specimen is studied. Statistically designed experiments have been conducted for finding the optimum process parameter setting for enhancing the storage modulus. Dynamic Mechanical Analysis has been used to understand the viscoelastic properties at various parameter settings. At the optimal parameter setting the storage modulus and loss modulus of the ABS-RP specimen was 1008 and 259.9 MPa respectively. The relative percentage contribution of slice height and raster width on the viscoelastic properties of the FDM-RP components was found to be 55 and 31 % respectively.

Effects of cooling rate and stabilization annealing on fatigue behavior of β-processed Ti-6Al-4V alloys

NASA Astrophysics Data System (ADS)

Seo, Wongyu; Jeong, Daeho; Lee, Dongjun; Sung, Hyokyung; Kwon, Yongnam; Kim, Sangshik

2017-07-01

The effects of stabilization annealing and cooling rate on high cycle fatigue (HCF) and fatigue crack propagation (FCP) behaviors of β-processed Ti64 alloys were examined. After β-process heating above β transus, two different cooling rates of air cooling (β-annealing) and water quenching (β-quenching) were utilized. Selected specimens were then underwent stabilization annealing. The tensile tests, HCF and FCP tests on conducted on the β-processed Ti64 specimens with and without stabilization annealing. No notable microstructural and mechanical changes with stabilization annealing was observed for the β-annealed Ti64 alloys. However, significant effect of stabilization annealing was found on the FCP behavior of β-quenched Ti64 alloys, which appeared to be related to the built-up of residual stress after quenching. The mechanical behavior of β-processed Ti64 alloys with and with stabilization annealing was discussed based on the micrographic examination, including crack growth path and crack nucleation site, and fractographic analysis.

Powder processing and mechanical properties of Silver0.86Lead19Antimony telluride20 (LAST) and Lead0.95Tin0.05Tellurium - Lead sulfide 8% (Lead telluride -Lead sulfide) thermoelectric materials

NASA Astrophysics Data System (ADS)

Ni, Jennifer Elisabeth

Thermoelectric (TE) materials convert between thermal and electrical energy and when used with existing processes will increase the efficiency via waste heat recovery. Ag0.86Pb19SbTe20 (LAST) and Pb0.95Sn0.05Te - PbS 8% (PbTe-PbS) materials exhibit good thermoelectric (TE) properties and have potential applications as thermoelectric generators in waste heat recovery. However, to fully characterize the thermo-mechanical behavior of LAST and PbTe-PbS materials under in-service conditions, knowledge is needed of the mechanical and thermal properties at room and high temperature. As fracture strength is inversely proportional to the square root of grain size, cast ingots were powder processed to reduce powder particle size. Three different powder processing methods were used (1) dry milling only, (2) wet milling only, or (3) dry milling and wet milling The specimens were fabricated using hot pressing or pulsed electric current sintering (PECS) from planetary ball milled powders. In this study, elastic moduli, including Young's modulus, shear modulus, and Poisson's ratio, were measured dynamically using resonant ultrasound spectroscopy (RUS) at room temperature and as a function of temperature up to 663 K. The room temperature porosity dependence for Young's modulus followed the empirical exponential relationships common for brittle materials, with a material dependent constant bPE of 3.5 and 1.3 for LAST and PbTe-PbS, respectively. The room temperature Young's modulus for a theoretically dense specimen was 58.4 +/- 0.6 GPa and 56.2 +/- 0.4 GPa for for LAST and PbTe-PbS, respectively. For hot pressed PbTe-PbS specimens, the Vickers indentations mean hardness and fracture toughness was 1.18 + 0.09 GPa and 0.35 +/- 0.04 MPa·m 1/2. The coefficient of thermal expansion is important for understanding the mechanical response of a material to a thermal gradient or a thermal transient. For PbTe-PbS the coefficient of thermal expansion measured using dilatometry and high temperature x-ray diffraction was 21.5 x 10-6 K -1. Bloating during post-densification annealing was measured indirectly using resonant ultrasound spectroscopy and dilatometry and directly using scanning electron microscopy. Dry milled only PECS-processed PbTe-PbS specimens did not bloat during post-densification anneals up to 936 K. Hot pressed and PECS-processed specimens processed from wet milled and dry and wet milled powder bloated during densification anneals at temperatures over 603 K.

Fabrication and evaluation of advanced titanium structural panels for supersonic cruise aircraft

NASA Technical Reports Server (NTRS)

Payne, L.

1977-01-01

Flightworthy primary structural panels were designed, fabricated, and tested to investigate two advanced fabrication methods for titanium alloys. Skin-stringer panels fabricated using the weldbraze process, and honeycomb-core sandwich panels fabricated using a diffusion bonding process, were designed to replace an existing integrally stiffened shear panel on the upper wing surface of the NASA YF-12 research aircraft. The investigation included ground testing and Mach 3 flight testing of full-scale panels, and laboratory testing of representative structural element specimens. Test results obtained on full-scale panels and structural element specimens indicate that both of the fabrication methods investigated are suitable for primary structural applications on future civil and military supersonic cruise aircraft.

Net shaped high performance oxide ceramic parts by selective laser melting

NASA Astrophysics Data System (ADS)

Yves-Christian, Hagedorn; Jan, Wilkes; Wilhelm, Meiners; Konrad, Wissenbach; Reinhart, Poprawe

An additive manufacturing technique (AM) for ceramics, based on Al2O3-ZrO2 powder by means of Selective Laser Melting (SLM) is presented. Pure ceramic powder is completely melted by a laser beam yielding net-shaped specimens of almost 100% densities without any post-processing. Possible crack formation during the build-up process due to thermal stresses is prevented by a high-temperature preheating of above 1600 ∘C. Specimens with fine-grained nano-sized microstructures and flexural strengths of above 500 MPa are produced. The new technology allows for rapid freeform manufacture of complex net-shaped ceramics, thus, exploiting the outstanding mechanical and thermal properties for high-end medical and engineering disciplines.

Cold plasma processing of local planetary ores for oxygen and metallurgically important metals

NASA Technical Reports Server (NTRS)

Lynch, D. C.; Bullard, D.; Ortega, R.

1991-01-01

The utilization of a cold or nonequilibrium plasma in chlorination processing is discussed. Titanium dioxide (TiO2) was successfully chlorinated at temperatures between 700 and 900 C without the aid of carbon. In addition to these initial experiments, a technique was developed for determining the temperature of a specimen in a plasma. Development of that technique has required evaluating the emissivity of TiO2, ZrO2, and FeOTiO2 and analyzing the specimen temperature in a plasma as a function of both power absorbed by the plasma and the pressure of the plasma. The mass spectrometer was also calibrated with TiCl4 and CCl4 vapor.

National survey on the pre-analytical variability in a representative cohort of Italian laboratories.

PubMed

Lippi, Giuseppe; Montagnana, Martina; Giavarina, Davide

2006-01-01

Owing to remarkable advances in automation, laboratory technology and informatics, the pre-analytical phase has become the major source of variability in laboratory testing. The present survey investigated the development of several pre-analytical processes within a representative cohort of Italian clinical laboratories. A seven-point questionnaire was designed to investigate the following issues: 1a) the mean outpatient waiting time before check-in and 1b) the mean time from check-in to sample collection; 2) the mean time from sample collection to analysis; 3) the type of specimen collected for clinical chemistry testing; 4) the degree of pre-analytical automation; 5a) the number of samples shipped to other laboratories and 5b) the availability of standardised protocols for transportation; 6) the conditions for specimen storage; and 7) the availability and type of guidelines for management of unsuitable specimens. The questionnaire was administered to 150 laboratory specialists attending the SIMEL (Italian Society of Laboratory Medicine) National Meeting in June 2006. 107 questionnaires (71.3%) were returned. Data analysis revealed a high degree of variability among laboratories for the time required for check-in, outpatient sampling, sample transportation to the referral laboratory and analysis upon the arrival. Only 31% of laboratories have automated some pre-analytical steps. Of the 87% of laboratories that ship specimens to other facilities without sample preparation, 19% have no standardised protocol for transportation. For conventional clinical chemistry testing, 74% of the laboratories use serum evacuated tubes (59% with and 15% without serum separator), whereas the remaining 26% use lithium-heparin evacuated tubes (11% with and 15% without plasma separator). The storage period and conditions for rerun/retest vary widely. Only 63% of laboratories have a codified procedure for the management of unsuitable specimens, which are recognised by visual inspection (69%) or automatic detection (29%). Only 56% of the laboratories have standardised procedures for the management of unsuitable specimens, which vary widely on a local basis. The survey highlights broad heterogeneity in several pre-analytical processes among Italian laboratories. The lack of reliable guidelines encompassing evidence-based practice is a major problem for the standardisation of this crucial part of the testing process and represents a major challenge for laboratory medicine in the 2000s.

Does imprint cytology improve the accuracy of transrectal prostate needle biopsy?

PubMed

Sayar, Hamide; Bulut, Burak Besir; Bahar, Abdulkadir Yasir; Bahar, Mustafa Remzi; Seringec, Nurten; Resim, Sefa; Çıralık, Harun

2015-02-01

To evaluate the accuracy of imprint cytology of core needle biopsy specimens in the diagnosis of prostate cancer. Between December 24, 2011 and May 9, 2013, patients with an abnormal DRE and/or serum PSA level of >2.5 ng/mL underwent transrectal prostate needle biopsy. Samples with positive imprint cytology but negative initial histologic exam underwent repeat sectioning and histological examination. 1,262 transrectal prostate needle biopsy specimens were evaluated from 100 patients. Malignant imprint cytology was found in 236 specimens (18.7%), 197 (15.6%) of which were confirmed by histologic examination, giving an initial 3.1% (n = 39) rate of discrepant results by imprint cytology. Upon repeat sectioning and histologic examination of these 39 biopsy samples, 14 (1.1% of the original specimens) were then diagnosed as malignant, 3 (0.2%) as atypical small acinar proliferation (ASAP), and 5 (0.4%) as high-grade prostatic intraepithelial neoplasia (HGPIN). Overall, 964 (76.4%) specimens were negative for malignancy by imprint cytology. Seven (0.6%) specimens were benign by cytology but malignant cells were found on histological evaluation. On imprint cytology examination, nonmalignant but abnormal findings were seen in 62 specimens (4.9%). These were all due to benign processes. After reexamination, the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false-positive rate, false-negative rate of imprint preparations were 98.1, 96.9, 98.4, 92.8, 99.3, 1.6, 3.1%, respectively. Imprint cytology is valuable tool for evaluating TRUS-guided core needle biopsy specimens from the prostate. Use of imprint cytology in combination with histopathology increases diagnostic accuracy when compared with histopathologic assessment alone. © 2014 Wiley Periodicals, Inc.

Restoration of an academic historical gross pathology collection-refreshed impact on current medical teaching?

PubMed

Eichhorn, Philip; Andraschke, Udo; Dross, Fritz; Geppert, Carol I; Hartmann, Arndt; Rau, Tilman T

2018-05-10

The declaration of Leiden pronounces the demand to conserve pathological-anatomical collections as cultural heritage. Likewise, the Institute of Pathology of the Friedrich-Alexander-University Erlangen-Nuremberg owns macroscopic pathological-anatomical specimens reaching back over 150 years. The purpose of this work is to examine the impact, meaning, and perception of such historical preparations during the current medical curriculum. Additionally, the experiences from the renovation process can be used as a template for other institutes. All preparations were documented, photographed, and catalogued in an electronic database. During a restoration period, a series of didactically suitable specimens were professionally restored. Hereby, the help of a special course of interested students was admitted. In a second step, the specimens were integrated into the regular teaching of students in macroscopic pathology. An evaluation was carried out on two student cohorts with and without historical specimens by means of a questionnaire with 23 items and two free text fields. In total, 1261 specimens were registered covering diseases from almost the complete human body with a strong representation of the cardiovascular, urinary, gastrointestinal, and central nervous systems. Hereby, exceptional rare and untreated cases with medical relevance could be found and stepwise implemented into the curriculum. The student evaluation positively addressed that the courses became livelier and interactive. Furthermore, a more comprehensive overview and a better understanding of the macroscopic pathology were appreciated. However, more self-study time with the specimen was demanded. The authenticity of historical specimens contrasts with the tendency to carry out virtual "online" didactic methods. The stereoscopic view on often untreated and, therefore, unbiased cases enhances a skill-oriented deeper understanding of diseases. In conclusion, historical specimens regain interest and even didactic value, especially in an era of declining autopsy rates.

Prediction and Verification of Ductile Crack Growth from Simulated Defects in Strength Overmatched Butt Welds

NASA Technical Reports Server (NTRS)

Nishioka, Owen S.

1997-01-01

Defects that develop in welds during the fabrication process are frequently manifested as embedded flaws from lack of fusion or lack of penetration. Fracture analyses of welded structures must be able to assess the effect of such defects on the structural integrity of weldments; however, the transferability of R-curves measured in laboratory specimens to defective structural welds has not been fully examined. In the current study, the fracture behavior of an overmatched butt weld containing a simulated buried, lack-of-penetration defect is studied. A specimen designed to simulate pressure vessel butt welds is considered; namely, a center crack panel specimen, of 1.25 inch by 1.25 inch cross section, loaded in tension. The stress-relieved double-V weld has a yield strength 50% higher than that of the plate material, and displays upper shelf fracture behavior at room temperature. Specimens are precracked, loaded monotonically while load-CMOD measurements are made, then stopped and heat tinted to mark the extent of ductile crack growth. These measurements are compared to predictions made using finite element analysis of the specimens using the fracture mechanics code Warp3D, which models void growth using the Gurson-Tvergaard dilitant plasticity formulation within fixed sized computational cells ahead of the crack front. Calibrating data for the finite element analyses, namely cell size and initial material porosities are obtained by matching computational predictions to experimental results from tests of welded compact tension specimens. The R-curves measured in compact tension specimens are compared to those obtained from multi-specimen weld tests, and conclusions as to the transferability of R-curves is discussed.

Blood culture accuracy: discards from central venous catheters in pediatric oncology patients in the emergency department.

PubMed

Winokur, Elizabeth J; Pai, Debra; Rutledge, Dana N; Vogel, Kate; Al-Majid, Sadeeka; Marshall, Christine; Sheikewitz, Paul

2014-07-01

Lack of specific guidelines regarding collection of blood for culture from central venous catheters (CVCs) has led to inconsistencies in policies among hospitals. Currently, no specific professional or regulatory recommendations exist in relation to using, reinfusing, or discarding blood drawn from CVCs before drawing blood for a culture. Repeated wasting of blood may harm immunocompromised pediatric oncology patients. The purpose of this comparative study was to determine whether differences exist between blood cultures obtained from the first 5 mL of blood drawn from a CVC line when compared with the second 5 mL drawn. During 2009-2011, 62 pediatric oncology patients with CVCs and orders for blood cultures to determine potential sepsis were enrolled during ED visits. Trained study nurses aseptically drew blood and injected the normally discarded first 5 mL and the second specimen (usual care) into separate culture bottles. Specimens were processed in the microbiology laboratory per hospital policy. Positive cultures were evaluated to assess agreement between specimen results and to determine that the identified pathogen was not a contaminant. Out of 186 blood culture pairs, 4.8% demonstrated positive results. In all positive-positive matches, the normal discard specimen contained the same organism as the usual care specimen. In 4 matches, the normally discarded specimen demonstrated notably earlier time to positivity (4 to 31 hours) compared with the usual care specimen, which resulted in earlier initiation of definitive antibiotics. These findings support the accuracy of the specimen that is normally discarded and suggest the need to reconsider its use for blood culture testing. Copyright © 2014 Emergency Nurses Association. Published by Mosby, Inc. All rights reserved.

Signal processing methods for in-situ creep specimen monitoring

NASA Astrophysics Data System (ADS)

Guers, Manton J.; Tittmann, Bernhard R.

2018-04-01

Previous work investigated using guided waves for monitoring creep deformation during accelerated life testing. The basic objective was to relate observed changes in the time-of-flight to changes in the environmental temperature and specimen gage length. The work presented in this paper investigated several signal processing strategies for possible application in the in-situ monitoring system. Signal processing methods for both group velocity (wave-packet envelope) and phase velocity (peak tracking) time-of-flight were considered. Although the Analytic Envelope found via the Hilbert transform is commonly applied for group velocity measurements, erratic behavior in the indicated time-of-flight was observed when this technique was applied to the in-situ data. The peak tracking strategies tested had generally linear trends, and tracking local minima in the raw waveform ultimately showed the most consistent results.

Experimental analysis of graphene nanocomposite on Kevlar

NASA Astrophysics Data System (ADS)

Manigandan, S.; Gunasekar, P.; Nithya, S.; Durga Revanth, G.; Anudeep, A. V. S. C.

2017-08-01

Graphene nanocomposite is a two dimensional structure which has intense role in material science. This paper investigates the topological property of the graphene nanocomposite doped in Kevlar fiber by direct mixing process. The Kevlar fiber by direct mixing process. The Kevlar fiber taken as the specimen which is fabricated by vacuum bag moulding process. Epoxy used as resin and HY951 as hardener. Three different specimens are fabricated based on the percentage of graphene nanocomposite 2%, 5%, 10% and 20% respectively. We witnessed the strength of the Kevlar fiber is increased when it is treated with nanocomposite. The percentage of the nanocomposite increase the strength of the fiber is increased. However as the nanocomposite beyond 5% the strength of fiber is dropped. In addition, we also seen the interfacial property of the fiber is dropped when the nanocomposite is added beyond threshold limit.

Surface Fatigue Tests Of M50NiL Gears And Bars

NASA Technical Reports Server (NTRS)

Townsend, Dennis P.; Bamberger, Eric N.

1994-01-01

Report presents results of tests of steels for use in gears and bearings of advanced aircraft. Spur-gear endurance tests and rolling-element surface fatigue tests performed on gear and bar specimens of M50NiL steel processed by vacuum induction melting and vacuum arc remelting (VIM-VAR). Compares results of tests with similar tests of specimens of VIM-VAR AISI 9310 steel and of AISI 9310 steel subjected to VAR only.

Use of Novel Technologies to Identify and Investigate Molecular Markers for Ovarian Cancer Screening and Prevention

DTIC Science & Technology

1999-10-01

using the peptide assay. Initial results from the analysis reveal a high background of this assay, i.e. non -specific binding of sera to the coating...on known or suspected epidemiological risk factors for ovarian cancer, including: menstrual and reproductive history; use of exogenous hormones (oral...required to complete a review process for use of said specimens. All specimens transferred to non -Project Investigators must receive approval and/or

Microgravity

NASA Image and Video Library

1998-01-25

CT scans of the spcimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. These views depict vertical slices from side to middle of a flight specimen. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: Los Alamos National Laboratory and the University of Colorado at Boulder.

Microgravity

NASA Image and Video Library

1998-01-25

CT scans of the spcimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. This view depict horizontal slices from top to bottom of a flight specimen. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: Los Alamos National Laboratory and the University of Colorado at Boulder.

Fully automated measurement of field-dependent AMS using MFK1-FA Kappabridge equipped with 3D rotator

NASA Astrophysics Data System (ADS)

Chadima, Martin; Studynka, Jan

2013-04-01

Low-field magnetic susceptibility of paramagnetic and diamagnetic minerals is field-independent by definition being also field-independent in pure magnetite. On the other hand, in pyrrhotite, hematite and high-Ti titanomagnetite it may be clearly field-dependent. Consequently, the field-dependent AMS enables the magnetic fabric of the latter group of minerals to be separated from the whole-rock AMS. The methods for the determination of the field-dependent AMS consist of separate measurements of each specimen in several fields within the Rayleigh Law range and subsequent processing in which the field-independent and field-dependent AMS components are calculated. The disadvantage of this technique is that each specimen must be measured several times, which is relatively laborious and time consuming. Recently, a new 3D rotator was developed for the MFK1-FA Kappabridge, which rotates the specimen simultaneously about two axes with different velocities. The measurement is fully automated in such a way that, once the specimen is inserted into the rotator, it requires no additional manipulation to measure the full AMS tensor. Consequently, the 3D rotator enables to measure the AMS tensors in the pre-set field intensities without any operator interference. Whole procedure is controlled by newly developed Safyr5 software; once the measurements are finished, the acquired data are immediately processed and can be visualized in a standard way.

Evaluation of powder metallurgy superalloy disk materials

NASA Technical Reports Server (NTRS)

Evans, D. J.

1975-01-01

A program was conducted to develop nickel-base superalloy disk material using prealloyed powder metallurgy techniques. The program included fabrication of test specimens and subscale turbine disks from four different prealloyed powders (NASA-TRW-VIA, AF2-1DA, Mar-M-432 and MERL 80). Based on evaluation of these specimens and disks, two alloys (AF2-1DA and Mar-M-432) were selected for scale-up evaluation. Using fabricating experience gained in the subscale turbine disk effort, test specimens and full scale turbine disks were formed from the selected alloys. These specimens and disks were then subjected to a rigorous test program to evaluate their physical properties and determine their suitability for use in advanced performance turbine engines. A major objective of the program was to develop processes which would yield alloy properties that would be repeatable in producing jet engine disks from the same powder metallurgy alloys. The feasibility of manufacturing full scale gas turbine engine disks by thermomechanical processing of pre-alloyed metal powders was demonstrated. AF2-1DA was shown to possess tensile and creep-rupture properties in excess of those of Astroloy, one of the highest temperature capability disk alloys now in production. It was determined that metallographic evaluation after post-HIP elevated temperature exposure should be used to verify the effectiveness of consolidation of hot isostatically pressed billets.

Toxicological analysis of formalin-fixed or embalmed tissues: a review.

PubMed

Nikolaou, Panagiota; Papoutsis, Ioannis; Dona, Artemisia; Spiliopoulou, Chara; Athanaselis, Sotiris

2013-12-10

During the autopsy of forensic cases, when there is no suspicion of drug use or chemical exposure, biological fluids may not be obtained for toxicological analysis, while specimens of tissues may be collected and preserved in a formalin solution for histological examination. When specific questions arise after the burial, the only possible options are the exhumation of an embalmed body or the toxicological analysis of the formalin-fixed specimens. The drug concentrations in these specimens can be altered due to the extraction efficiency and/or the chemical activity of the formalin solutions used during chemical fixation or embalming process. The aim of this paper is to review the published studies about the determination of specific groups of drugs in formalin-fixed or embalmed specimens and their stability after chemical fixation or embalming process. The analytical aspects of this determination are also discussed. The stability of drugs in formalin environment and the possible reaction of the drugs with formaldehyde, which is a highly reactive chemical substance, should always be considered during post-mortem/post-embalming forensic analysis. The additional analysis of the formalin solution in which the tissue was preserved is considered necessary. The identification and the evaluation of the possible degradation products or chemical derivatives are extremely useful during the interpretation of the results. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

A study of hydrogen environment effects on microstructure property behavior of NASA-23 alloy and related alloy systems

NASA Technical Reports Server (NTRS)

Diwan, Ravinder M.

1990-01-01

This work is part of the overall advanced main combustion chamber (AMCC) casting characterization program of the Materials and Processes Laboratory of the Marshall Space Flight Center. The influence of hydrogen on the tensile properties and ductility behavior of NASA-23 alloy were analyzed. NASA-23 and other referenced alloys in cast and hipped conditions were solution treated and aged under selected conditions and characterized using optical metallography, scanning electron microscopy, and electron microprobe analysis techniques. The yield strength of NASA-23 is not affected much by hydrogen under tensile tests carried at 5000 psig conditions; however, the ultimate strength and ductility properties are degraded. This implies that the physical mechanisms operating would be related to the plastic deformation process. The fracture surfaces characteristics of NASA-23 specimens tensile tested in hydrogen, helium, and air were also analyzed. These revealed surface cracks around specimen periphery with the fracture surface showing a combination of intergranular and transgranular modes of fracture. It is seen that the specimens charged in hydrogen seem to favor a more brittle fracture mode in comparison to air and helium charged specimens. The AMCC casting characterization program is to be analyzed for their hydrogen behavior. As a result of this program, the basic microstructural factors and fracture characteristics in some cases were analyzed.

Microgravity

NASA Image and Video Library

1998-01-25

CT scans of the specimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. This view is made from three orthogonal slices. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. (Credit: Los Alamos National Laboratory and the University of Colorado at Boulder).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meisner, L. L., E-mail: llm@isps.tsc.ru; Meisner, S. N.; National Research Tomsk State University, 36, Lenina Avenue, Tomsk, 634050

The corrosion resistance behavior and cytotoxicity of binary NiTi-base alloy specimens subjected to surface modification by silicon ion beams and the proliferative ability of mesenchymal stem cells (MSC) of rat marrow on an ion-implanted surface of the alloy have been studied. The silicon ion beam processing of specimen surfaces is shown to bring about a nearly two-fold improvement in the corrosion resistance of the material to attack by acqueous solutions of NaCl and human plasma and a drastic decrease in the nickel concentration after immersion of the specimens into the solutions for ∼3400 and ∼6000 h, respectively. It is foundmore » that MSC proliferation strongly depends on the surface structure, roughness and chemical condition of NiTi implants.« less

Application of neural networks in the acousto-ultrasonic evaluation of metal-matrix composite specimens

NASA Technical Reports Server (NTRS)

Cios, Krzysztof J.; Tjia, Robert E.; Vary, Alex; Kautz, Harold E.

1992-01-01

Acousto-ultrasonics (AU) is a nondestructive evaluation (NDE) technique that was devised for the testing of various types of composite materials. A study has been done to determine how effectively the AU technique may be applied to metal-matrix composites (MMCs). The authors use the results and data obtained from that study and apply neural networks to them, particularly in the assessment of mechanical property variations of a specimen from AU measurements. It is assumed that there is no information concerning the important features of the AU signal which relate to the mechanical properties of the specimen. Minimally processed AU measurements are used while relying on the network's ability to extract the significant features of the signal.

Role of plastic deformation in wear of copper and copper - 10-percent-aluminum alloy in cryogenic fuels

NASA Technical Reports Server (NTRS)

Bill, R. C.; Wisander, D. W.

1973-01-01

High-purity copper specimens and a copper-aluminum (10%) alloy specimen were subjected to sliding against Type 440 C in cryogenic fuel environments. It was found that virtually all wear occurred by the plastic deformation of a recrystallized layer extending to about 10 micrometers below the wear scar surface of the copper or copper alloy. The wear debris was in the form of a layered structure adhering to the exit region of the wear scar. Measurements on the high purity copper specimens indicated that the wear rate was proportional to the applied load and to the sliding velocity squared. A physical model of the wear process is proposed to account for these observations.

Damage progression in Composite Structures

NASA Technical Reports Server (NTRS)

Minnetyan, Levon

1996-01-01

A computational simulation tool is used to evaluate the various stages of damage progression in composite materials during Iosipescu sheat testing. Unidirectional composite specimens with either the major or minor material axis in the load direction are considered. Damage progression characteristics are described for each specimen using two types of boundary conditions. A procedure is outlined regarding the use of computational simulation in composites testing. Iosipescu shear testing using the V-notched beam specimen is a convenient method to measure both shear strength and shear stiffness simultaneously. The evaluation of composite test response can be made more productive and informative via computational simulation of progressive damage and fracture. Computational simulation performs a complete evaluation of laminated composite fracture via assessment of ply and subply level damage/fracture processes.

Study of plastic strain localization mechanisms caused by nonequilibrium transitions in mesodefect ensembles under high-speed loading

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sokovikov, Mikhail, E-mail: sokovikov@icmm.ru; Chudinov, Vasiliy; Bilalov, Dmitry

2015-10-27

The behavior of specimens dynamically loaded during split Hopkinson (Kolsky) bar tests in a regime close to simple shear conditions was studied. The lateral surface of the specimens was investigated in-situ using a high-speed infrared camera CEDIP Silver 450M. The temperature field distribution obtained at different time allowed one to trace the evolution of plastic strain localization. The process of target perforation involving plug formation and ejection was examined using a high-speed infrared camera and a VISAR velocity measurement system. The microstructure of tested specimens was analyzed using an optical interferometer-profiler and a scanning electron microscope. The development of plasticmore » shear instability regions has been simulated numerically.« less

Manufacturing Feasibility and Forming Properties of Cu-4Sn in Selective Laser Melting.

PubMed

Mao, Zhongfa; Zhang, David Z; Wei, Peitang; Zhang, Kaifei

2017-03-24

Copper alloys, combined with selective laser melting (SLM) technology, have attracted increasing attention in aerospace engineering, automobile, and medical fields. However, there are some difficulties in SLM forming owing to low laser absorption and excellent thermal conductivity. It is, therefore, necessary to explore a copper alloy in SLM. In this research, manufacturing feasibility and forming properties of Cu-4Sn in SLM were investigated through a systematic experimental approach. Single-track experiments were used to narrow down processing parameter windows. A Greco-Latin square design with orthogonal parameter arrays was employed to control forming qualities of specimens. Analysis of variance was applied to establish statistical relationships, which described the effects of different processing parameters (i.e., laser power, scanning speed, and hatch space) on relative density (RD) and Vickers hardness of specimens. It was found that Cu-4Sn specimens were successfully manufactured by SLM for the first time and both its RD and Vickers hardness were mainly determined by the laser power. The maximum value of RD exceeded 93% theoretical density and the maximum value of Vickers hardness reached 118 HV 0.3/5. The best tensile strength of 316-320 MPa is inferior to that of pressure-processed Cu-4Sn and can be improved further by reducing defects.

Hydrothermal solidification of municipal solid waste incineration bottom ash with slag addition.

PubMed

Jing, Zhenzi; Ran, Xianqiang; Jin, Fangming; Ishida, Emile H

2010-01-01

Hydrothermal solidification of municipal solid waste incineration (MSWI) bottom ash has been carried out under saturated steam pressure (1.56 MPa) at 200 degrees C for up to 24 h by mixing quartz, slaked lime and water-cooled blast furnace slag (WBFS). The strength enhancement for the WBFS addition was best. The strength development was shown to be due mainly to tobermorite formation, and the tobermorite formation densified matrix, thus promoting the strength development. WBFS seemed to have a higher reactivity than the quartz during the initial hydrothermal process, which provided more silica available to harden the solidified specimens. However, a longer curing time (24 h) was favorable to the quartz dissolution for tobermorite formation, which in turn, enhanced the strength for quartz addition. Curing time affected the crystal morphology evolution, and the stubby plate of tobermorite seemed to result in a high strength enhancement in this study. Laboratory leaching tests were conducted to determine the amount of heavy metals dissolved from the final solidified specimens, and the leaching results showed that after hydrothermal processing the heavy metals dissolved from the solidified specimens were reduced effectively. As such, the hydrothermal processing may have a high potential for recycling/reusing MSWI ash on a large scale. 2010 Elsevier Ltd. All rights reserved.

An Interagency Study of Depainting Techniques

NASA Technical Reports Server (NTRS)

Cook, B.

1997-01-01

Many popular and widely used paint stripping products now contain methylene chloride as their active ingredient. However, the Environmental Protection Agency (EPA) will critically curb the use of methylene chloride under an aerospace national emission standard for hazardous air pollutants (NESHAP) within the next 2-1/2 years. An effort is underway to identify and evaluate alternative depainting technologies emphasizing those believed to be both effective and environmentally benign. On behalf of the EPA and in cooperation with the U. S. Air Force (USAF), the National Aeronautics and Space Administration (NASA) is conducting a technical assessment of nine alternative technologies (i.e.: chemical stripping, two CO2 blasting processes, FLASHJET(TM) coating removal, laser stripping, plastic media blasting, sodium bicarbonate wet stripping, high-pressure water stripping, and wheat starch blasting). These depainting processes represent five removal method categories, namely abrasive, impact, cryogenic, thermal, and/or molecular bonding dissociation. This paper discusses the test plan and parameters for this interagency study. Several thicknesses of clad and non-clad aluminum substrates were used to prepare test specimens, which have been cut, cleaned, painted, and environmentally aged. Each depainting process has been assigned a specimen lot, which is now undergoing an initial strip cycle. Metallurgical impacts will be determined after these specimens complete five cycles of preparation and stripping.

Fatigue lifetime prediction of a reduced-diameter dental implant system: Numerical and experimental study.

PubMed

Duan, Yuanyuan; Gonzalez, Jorge A; Kulkarni, Pratim A; Nagy, William W; Griggs, Jason A

2018-06-16

To validate the fatigue lifetime of a reduced-diameter dental implant system predicted by three-dimensional finite element analysis (FEA) by testing physical implant specimens using an accelerated lifetime testing (ALT) strategy with the apparatus specified by ISO 14801. A commercially-available reduced-diameter titanium dental implant system (Straumann Standard Plus NN) was digitized using a micro-CT scanner. Axial slices were processed using an interactive medical image processing software (Mimics) to create 3D models. FEA analysis was performed in ABAQUS, and fatigue lifetime was predicted using fe-safe ® software. The same implant specimens (n=15) were tested at a frequency of 2Hz on load frames using apparatus specified by ISO 14801 and ALT. Multiple step-stress load profiles with various aggressiveness were used to improve testing efficiency. Fatigue lifetime statistics of physical specimens were estimated in a reliability analysis software (ALTA PRO). Fractured specimens were examined using SEM with fractographic technique to determine the failure mode. FEA predicted lifetime was within the 95% confidence interval of lifetime estimated by experimental results, which suggested that FEA prediction was accurate for this implant system. The highest probability of failure was located at the root of the implant body screw thread adjacent to the simulated bone level, which also agreed with the failure origin in physical specimens. Fatigue lifetime predictions based on finite element modeling could yield similar results in lieu of physical testing, allowing the use of virtual testing in the early stages of future research projects on implant fatigue. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

Corrosion in artificial saliva of a Ni-Cr-based dental alloy joined by TIG welding and conventional brazing.

PubMed

Matos, Irma C; Bastos, Ivan N; Diniz, Marília G; de Miranda, Mauro S

2015-08-01

Fixed prosthesis and partial dental prosthesis frameworks are usually made from welded Ni-Cr-based alloys. These structures can corrode in saliva and have to be investigated to establish their safety. The purpose of this study was to evaluate the corrosion behavior of joints joined by tungsten inert gas (TIG) welding and conventional brazing in specimens made of commercial Ni-Cr alloy in Fusayama artificial saliva at 37°C (pH 2.5 and 5.5). Eighteen Ni-Cr base metal specimens were cast and welded by brazing or tungsten inert gas methods. The specimens were divided into 3 groups (base metal, 2 welded specimens), and the composition and microstructure were qualitatively evaluated. The results of potential corrosion and corrosion current density were analyzed with a 1-way analysis of variance and the Tukey test for pairwise comparisons (α=.05). Base metal and tungsten inert gas welded material showed equivalent results in electrochemical corrosion tests, while the air-torched specimens exhibited low corrosion resistance. The performance was worst at pH 2.5. These results suggest that tungsten inert gas is a suitable welding process for use in dentistry, because the final microstructure does not reduce the corrosion resistance in artificial saliva at 37°C, even in a corrosion-testing medium that facilitates galvanic corrosion processes. Moreover, the corrosion current density of brazed Ni-Cr alloy joints was significantly higher (P<.001) than the base metal and tungsten inert gas welded joints. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Defects-tolerant Co-Cr-Mo dental alloys prepared by selective laser melting.

PubMed

Qian, B; Saeidi, K; Kvetková, L; Lofaj, F; Xiao, C; Shen, Z

2015-12-01

CrCoMo alloy specimens were successfully fabricated using selective laser melting (SLM). The aim of this study was to carefully investigate microstructure of the SLM specimens in order to understand the influence of their structural features inter-grown on different length scales ranging from nano- to macro-levels on their mechanical properties. Two different sets of processing parameters developed for building the inner part (core) and the surface (skin) of dental prostheses were tested. Microstructures were characterized by SEM, EBSD and XRD analysis. The elemental distribution was assessed by EDS line profile analysis under TEM. The mechanical properties of the specimens were measured. The microstructures of both specimens were characterized showing formation of grains comprised of columnar sub-grains with Mo-enrichment at the sub-grain boundaries. Clusters of columnar sub-grains grew coherently along one common crystallographic direction forming much larger single crystal grains which are intercrossing in different directions forming an overall dendrite-like microstructure. Three types of microstructural defects were occasionally observed; small voids (<10 μm), fine cracks at grain boundaries (<10 μm) and cracks at weld line boundaries (>10 μm). Despite the presence of these defects, the yield and the ultimate tensile strength (UTS) were 870 and 430MPa and 1300MPa and 1160MPa, respectively, for the skin and core specimens which are higher than casted dental alloy. Although the formation of microstructural defects is hard to be avoided during the SLM process, the SLM CoCrMo alloys can achieve improved mechanical properties than their casted counterparts, implying they are "defect-tolerant". Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Microstructure Stability During Creep of Friction Stir Welded AA2024-T3 Alloy

NASA Astrophysics Data System (ADS)

Regev, Michael; Rashkovsky, Tal; Cabibbo, Marcello; Spigarelli, Stefano

2018-01-01

The poor weldability of the AA2024 aluminum alloy limits its use in industrial applications. Because friction stir welding (FSW) is a non-fusion welding process, it seems to be a promising solution for welding this alloy. In the current study, FSW was applied to butt weld AA2024-T3 aluminum alloy plates. Creep tests were conducted at 250 and at 315 °C on both the parent material and the friction stir welded specimens. The microstructures of the welded and non-welded AA2024-T3 specimens before and after the creep tests were studied and compared. A comprehensive transmission electron microscopy study together with a high-resolution scanning electron microscopy study and energy-dispersive x-ray spectroscopy analysis was conducted to investigate the microstructure stability. The parent material seems to contain two kinds of Cu-rich precipitates—coarse precipitates of a few microns each and uniformly dispersed fine nanosized precipitates. Unlike the parent material, the crept specimens were found to contain the two kinds of precipitates mentioned above together with platelet-like precipitates. In addition, extensive decoration of the grain boundaries with precipitates was clearly observed in the crept specimens. Controlled aging experiments for up to 280 h at the relevant temperatures were conducted on both the parent material and the welded specimens in order to isolate the contribution of exposure to high temperatures to the microstructure changes. TEM study showed the development of dislocation networks into a cellular dislocation structure in the case of the parent metal. Changes in the dislocation structure as a function of the creep strain and the FSW process were recorded. A detailed creep data analysis was conducted, taking into account the instability of the microstructure.

Stress corrosion cracking of Zircaloys in unirradiated and irradiated CsI

NASA Astrophysics Data System (ADS)

Cox, B.; Surette, B. A.; Wood, J. C.

1986-03-01

Unirradiated split-ring specimens of Zircaloy fuel cladding, coated with CsI, cracked when stressed at elevated temperatures. The specimens have been reexamined fractographically and metallographically in order to confirm that the cause of cracking was stress corrosion (SCC) and not delayed hydride cracking (DHC). Further specimens have been cracked at 350°C by a solution of CsI in a fused mixture of nitrates of rubidium, cesium, strontium and barium, by a similar mechanism. CsI dissolved in a fused molybdate melt was not stable at 400°C, and rapidly evolved iodine, leaving a melt that was incapable of causing SCC. Irradiation of stressed split-ring specimens of Zircaloy fuel cladding in a γ-irradiator of 10 6 R/h and in the U-5 loop in the NRU reactor at an estimated 10 9 R/h caused SCC when the specimens were packed in dry CsI powder. Care had to be taken to dry the CsI, otherwise cracking occurred by a DHC mechanism from hydrogen absorbed from residual moisture in the CsI. Fractography showed that the crack surfaces obtained with dry CsI were typical of iodine-induced SCC rather than cesium-induced metal vapour embrittlement. Thus, if a transport process is provided for the iodide to obtain access to the zirconium surface, CsI is capable of causing SCC of Zircaloy. This transport process might be ionic diffusion in a fission product oxide melt in the fuel-clad gap, however, radiolysis of CsI to form a volatile iodine species in a radiation field is the more probable explanation of PCI failures.

The Peru Cervical Cancer Prevention Study (PERCAPS): the technology to make screening accessible.

PubMed

Levinson, Kimberly L; Abuelo, Carolina; Salmeron, Jorge; Chyung, Eunice; Zou, Jing; Belinson, Suzanne E; Wang, Guixiang; Ortiz, Carlos Santos; Vallejos, Carlos Santiago; Belinson, Jerome L

2013-05-01

This study utilized a combination of HPV self-sampling, iFTA elute specimen cards, and long distance transport for centralized processing of specimens to determine the feasibility of large-scale screening in remote and transient populations. This study was performed in two locations in Peru (Manchay and Iquitos). The "Just For Me" cervico-vaginal brush and iFTA elute cards were used for the collection and transport of specimens. Samples were shipped via FedEx to China and tested for 14 types of high-risk HPV using PCR based MALDI-TOF. HPV positive women were treated with cryotherapy after VIA triage, and followed-up with colposcopy, biopsy, ECC, and repeat HPV testing at 6 months. Six hundred and forty three women registered, and 632 returned a sample over a 10 day period. Within 2 weeks, specimens were shipped, samples tested, and results received by study staff. Sixty-eight women (10.8%) tested positive, and these results were delivered over 4 days. Fifty-nine HPV positive women (87%) returned for evaluation and treatment, and 2 had large lesions not suitable for cryotherapy. At 6 months, 42 women (74%) returned for follow-up, and 3 had CIN 2 (all positive samples from the endocervical canal). Ninety eight percent of participants reported that they would participate in this type of program again. Utilizing HPV self-sampling, solid media specimen cards for long distance transport, and centralized high throughput processing, we achieved rapid delivery of results, high satisfaction levels, and low loss to follow-up for cervical cancer screening in remote and transient populations. Copyright © 2013 Elsevier Inc. All rights reserved.

Evaluation of commercially available preservatives for laboratory detection of helminths and protozoa in human fecal specimens.

PubMed

Pietrzak-Johnston, S M; Bishop, H; Wahlquist, S; Moura, H; Da Silva, N D; Da Silva, S P; Nguyen-Dinh, P

2000-05-01

Formalin and mercuric chloride-based low-viscosity polyvinyl alcohol (LV-PVA) are widely used by most diagnostic parasitology laboratories for preservation of helminth eggs and protozoan cysts and trophozoites in fecal specimens. Concerns about the toxicity of formalin and the difficulty of disposal of LV-PVA are powerful incentives to use alternate preservatives. Such alternatives have been marketed by several companies and are often presented as one-vial, non-mercuric chloride fixatives that aim at performing the same role as formalin and PVA combined. We compared five, one-vial commercial preservatives, two from Meridian Diagnostics, Inc. (Ecofix and sodium acetate-acetic acid-formalin), and one each from Scientific Device Laboratories, Inc. (Parasafe), Alpha Tec Systems, Inc. (Proto-fix), and Streck Laboratories, Inc. (STF), with 10% formalin and LV-PVA. Fecal specimens obtained from patients in a Brazilian hospital were aliquoted within 12 h of collection into the seven preservatives mentioned above and were processed after 1 month at the Centers for Disease Control and Prevention. Direct and concentrated permanent smears as well as concentrates for 20 positive specimens (a total of 259 processed samples) were prepared, stained according to the manufacturers' instructions, examined, and graded. Positive specimens contained one or more parasites with stages consisting of eggs, larvae, cysts, and a few trophozoites of Giardia intestinalis. Criteria for assessment of the preservatives included the quality of the diagnostic characteristics of helminth eggs, protozoan cysts, and trophozoites, ease of use, and cost. Acceptable alternatives to formalin for wet preparations were found. Ecofix was found to be comparable to the traditional "gold standard" LV-PVA for the visualization of protozoa in permanent stained smears. This study suggests that more acceptable alternatives to the traditional formalin and LV-PVA exist.

Urine culture contamination: a College of American Pathologists Q-Probes study of 127 laboratories.

PubMed

Bekeris, Leonas G; Jones, Bruce Allen; Walsh, Molly K; Wagar, Elizabeth A

2008-06-01

While urine culture contamination may not be completely avoidable, some laboratories have lower contamination rates than others. A College of American Pathologists (CAP) 1998 Q-Probes study showed that many interventions commonly assumed to reduce contamination were not demonstrably effective. This article revisits the issue. To examine the frequency of urine culture contamination, review current laboratory practices in the collection of urine culture specimens, and determine practice characteristics that may be associated with the contamination rate. Laboratories participating in a CAP Q-Probes study were required to prospectively collect data on 120 consecutive urine culture specimens and provide information on the patient's demographics (age and sex), the location where the specimen was collected, how the specimen was handled, the number of isolates in quantities greater than or equal to 10,000 colony-forming units (CFU)/mL, and whether the laboratory considered the specimen to be contaminated. Specific inclusion and exclusion criteria were provided to the participants. Each laboratory completed a supplemental questionnaire that probed for specific laboratory urine culture collection practices. One hundred twenty-seven laboratories participated in the study. Results from a total of 14,739 urine specimens were received. For the purpose of this study, a urine specimen was determined to be contaminated if the culture yielded more than 2 isolates in quantities greater than or equal to 10,000 CFU/mL. Using these criteria the median institution had a contamination rate of 15.0%. Laboratories in the 10th percentile (low performance) had an average contamination rate of 41.7%, while laboratories in the 90th percentile had an average rate of 0.8%. The collection site had no influence on the contamination rate, but postcollection processing, especially refrigeration of the specimen, had a substantial effect. Providing instruction to patients produced a statistically significant lowering of contamination rates for specimens from male patients (P = .006) but not for female patients, except when written instructions were provided in the emergency room, in which case specimen contamination rates for both male and female patients dropped (P = .01). The median contamination rates remain at a level comparable to the results seen in a previous Q-Probes study, and some laboratories have very high contamination rates. Specimen refrigeration is associated with lower overall urine culture specimen contamination rate. Providing patient instruction is also associated with lower contamination rates under specific circumstances.

Activity-based differentiation of pathologists' workload in surgical pathology.

PubMed

Meijer, G A; Oudejans, J J; Koevoets, J J M; Meijer, C J L M

2009-06-01

Adequate budget control in pathology practice requires accurate allocation of resources. Any changes in types and numbers of specimens handled or protocols used will directly affect the pathologists' workload and consequently the allocation of resources. The aim of the present study was to develop a model for measuring the pathologists' workload that can take into account the changes mentioned above. The diagnostic process was analyzed and broken up into separate activities. The time needed to perform these activities was measured. Based on linear regression analysis, for each activity, the time needed was calculated as a function of the number of slides or blocks involved. The total pathologists' time required for a range of specimens was calculated based on standard protocols and validated by comparing to actually measured workload. Cutting up, microscopic procedures and dictating turned out to be highly correlated to number of blocks and/or slides per specimen. Calculated workload per type of specimen was significantly correlated to the actually measured workload. Modeling pathologists' workload based on formulas that calculate workload per type of specimen as a function of the number of blocks and slides provides a basis for a comprehensive, yet flexible, activity-based costing system for pathology.

Design and fabrication of a micron scale free-standing specimen for uniaxial micro-tensile tests

NASA Astrophysics Data System (ADS)

Tang, Jun; Wang, Hong; Li, Shi Chen; Liu, Rui; Mao, Sheng Ping; Li, Xue Ping; Zhang, Cong Chun; Ding, Guifu

2009-10-01

This paper presents a novel design and fabrication of test chips with a nickel free-standing specimen for the micro uniaxial tensile test. To fabricate test chips on the quartz substrate significantly reduces the fabrication time, minimizes the number of steps and eliminates the effect of the wet anisotropic etching process on mechanical properties. The test chip can be gripped tightly to the test machine and aligned accurately in the pulling direction; furthermore, the approximately straight design of the specimen rather than the traditional dog-bone structure enables the strain be directly measured by a displacement sensor. Both finite-element method (FEM) analysis and experimental results indicate the reliability of the new design. The test chip can also be extended to other materials. The experimental measured Young's modulus of a thin nickel film and the ultimate tensile strength are approximately 94.5 Gpa and 1.76 Gpa, respectively. The results were substantially supported by the experiment on larger gauge specimens by a commercial dynamic mechanical analysis (DMA) instrument. These specimens were electroplated under the same conditions. The low Young's modulus and the high ultimate tensile strength might be explained by the fine grain in the electroplated structure.

Influence of preservative and mounting media on the size and shape of monogenean sclerites.

PubMed

Fankoua, Severin-Oscar; Bitja Nyom, Arnold R; Bahanak, Dieu Ne Dort; Bilong Bilong, Charles F; Pariselle, Antoine

2017-08-01

Based on Cichlidogyrus sp. (Monogenea, Ancyrocephalidae) specimens from Hemichromis sp. hosts, we tested the influence of different methods to fix/preserve samples/specimens [frozen material, alcohol or formalin preserved, museum process for fish preservation (fixed in formalin and preserved in alcohol)] and different media used to mount the slides [tap water, glycerin ammonium picrate (GAP), Hoyer's one (HM)] on the size/shape of sclerotized parts of monogenean specimens. The results show that the use of HM significantly increases the size of haptoral sclerites [marginal hooks I, II, IV, V, and VI; dorsal bar length, width, distance between auricles and auricle length, ventral bar length and width], and changes their shape [angle opening between shaft and guard (outer and inner roots) in both ventral and dorsal anchors, ventral bar much wider, dorsal one less curved]. This influence seems to be reduced when specimens/samples are fixed in formalin. The systematics of Monogenea being based on the size and shape of their sclerotized parts, to prevent misidentifications or description of invalid new species, we recommend the use of GAP as mounting medium; Hoyer's one should be restricted to monogenean specimens fixed for a long time which are more shrunken.

Crack propagation from a filled flaw in rocks considering the infill influences

NASA Astrophysics Data System (ADS)

Chang, Xu; Deng, Yan; Li, Zhenhua; Wang, Shuren; Tang, C. A.

2018-05-01

This study presents a numerical and experimental study of the cracking behaviour of rock specimen containing a single filled flaw under compression. The primary aim is to investigate the influences of infill on crack patterns, load-displacement response and specimen strength. The numerical code RFPA2D (Rock Failure Process Analysis) featured by the capability of modeling heterogeneous materials is employed to develop the numerical model, which is further calibrated by physical tests. The results indicate that there exists a critical infill strength which controls crack patterns for a given flaw inclination angle. For case of infill strength lower than the critical value, the secondary or anti-cracks are disappeared by increasing the infill strength. If the infill strength is greater than the critical value, the filled flaw has little influence on the cracking path and the specimen fails by an inclined crack, as if there is no flaw. The load-displacement responses show specimen stiffness increases by increasing infill strength until the infill strength reaches its critical value. The specimen strength increases by increasing the infill strength and almost keeps constant as the infill strength exceeds its critical value.

NRL Review - 2009

DTIC Science & Technology

2009-01-01

for a fundamental physical understanding of electronic properties . The Materials Processing Facility includes appa- ratuses for powder production by...situ. Facilities to process powder into bulk specimens by hot and cold isostatic pressing permit a variety of consolidation possibilities. The iso...Synthesis/ Property Measurement Facility has special emphasis on polymers, surface-film processing , and directed self-assembly. The Chemical Vapor

A novel design for storage of inner stress by colloidal processing on rock-like materials

NASA Astrophysics Data System (ADS)

Chen, Weichang; Wang, Sijing; Lekan Olatayo, Afolagboye; Fu, Huanran

2018-06-01

Inner stress exists in rocks, affecting rock engineering, yet has received very little attention and quantitative investigation because of uncertainty about its characteristics. Previous studies have suggested that the inner stresses of rock materials are closely related to their physical state variation. In this work, a novel mold was designed to simulate the storage process of inner stress in specimens composed of quartz sands and epoxy. Then, thermal tests were carried out to change the physical state of the specimens, and expansion of the specimens was monitored. The results indicated that inner stress could be partly locked by the mold and it could also be released by heating. It can be inferred from the analysis that one necessary condition of storage and release of inner stress is physical state variation. Additionally, by using an XRD method, the variations in the interplanar spacing of the quartz sands were detected, and the results reflect that inner stress could be locked-in aggregates (quartz sands) by a cement constraint (solid epoxy). The inner stress stored in quartz sands was calculated using height and interplanar spacing variations.

Relative intranuclear magnesium and phosphorus contents in normal and tumor cells of the human thyroid gland as revealed by energy-dispersive X-ray microanalysis.

PubMed

Lukács, G L; Zs-Nagy, I; Steiber, J; Györi, F; Balázs, G

1996-01-01

Energy dispersive X-ray microanalysis was performed on altogether 42 surgically removed tissue specimens of 32 patients, which were taken either from intact thyroid parts or various histopathologically verified tumors of the thyroid gland. The tissue specimens were processed with the freeze-fracture-freeze-drying technique and then analyzed in the so-called bulk specimen form. The studies were carried out during the years 1980-81, when intranuclear monovalent ionic composition was studied in detail. From the retained total elemental peak list, it was possible to calculate retrospectively the relative intranuclear Mg and P contents. The data processed by nested (hierarchical) analysis of variance show that the intranuclear Mg content of the 5 diagnostic groups (normal thyroid tissue, thyroiditis, benign adenomas, differentiated carcinomas and undifferentiated thyroid tumors) increases significantly, in parallel with the increasing malignancy, but the P content remains unchanged. One can conclude that the elevated intranuclear Mg content in the tumors of high malignancy may be of diagnostic importance, and a warning signal for the therapeutic approaches based on Mg-supplementations.

Extracting alveolar structure of human lung tissue specimens based on surface skeleton representation from 3D micro-CT images

NASA Astrophysics Data System (ADS)

Ishimori, Hiroyuki; Kawata, Yoshiki; Niki, Noboru; Nakaya, Yoshihiro; Ohmatsu, Hironobu; Matsui, Eisuke; Fujii, Masashi; Moriyama, Noriyuki

2007-03-01

We have developed a Micro CT system for understanding lung function at a high resolution of the micrometer order (up to 5µm in spatial resolution). Micro CT system enables the removal specimen of lungs to be observed at micro level, has expected a big contribution for micro internal organs morphology and the image diagnosis study. In this research, we develop system to visualize lung microstructures in three dimensions from micro CT images and analyze them. They characterize in that high CT value of the noise area is, and the difficulty of only using threshold processing to extract the alveolar wall of micro CT images. Thus, we are developing a method of extracting the alveolar wall with surface thinning algorithm. In this report, we propose the method which reduces the excessive degeneracy of figure which caused by surface thinning process. And, we apply this algorithm to the micro CT image of the actual pulmonary specimen. It is shown that the extraction of the alveolus wall becomes possible in the high precision.

Retrodeformation and muscular reconstruction of ornithomimosaurian dinosaur crania

PubMed Central

Rayfield, Emily J.

2015-01-01

Ornithomimosaur dinosaurs evolved lightweight, edentulous skulls that possessed keratinous rhamphothecae. Understanding the anatomy of these taxa allows for a greater understanding of “ostrich-mimic” dinosaurs and character change during theropod dinosaur evolution. However, taphonomic processes during fossilisation often distort fossil remains. Retrodeformation offers a means by which to recover a hypothesis of the original anatomy of the specimen, and 3D scanning technologies present a way to constrain and document the retrodeformation process. Using computed tomography (CT) scan data, specimen specific retrodeformations were performed on three-dimensionally preserved but taphonomically distorted skulls of the deinocheirid Garudimimus brevipes Barsbold, 1981 and the ornithomimids Struthiomimus altus Lambe, 1902 and Ornithomimus edmontonicus Sternberg, 1933. This allowed for a reconstruction of the adductor musculature, which was then mapped onto the crania, from which muscle mechanical advantage and bite forces were calculated pre- and post-retrodeformation. The extent of the rhamphotheca was varied in each taxon to represent morphologies found within modern Aves. Well constrained retrodeformation allows for increased confidence in anatomical and functional analysis of fossil specimens and offers an opportunity to more fully understand the soft tissue anatomy of extinct taxa. PMID:26213655

Progressive Consent and Specimen Accrual Models to Address Sustainability: A Decade's Experience at an Oregon Biorepository.

PubMed

Ost, John A; Newton, Paul W; Neilson, Duncan R; Cioffi, Joseph A; Wackym, P Ashley; Perkins, R Serene

2017-02-01

The Legacy Biorepository is a College of American Pathologists-accredited biorepository operating within a seven-hospital healthcare system, with a decade's experience in specimen accrual, storage, and distribution. While standardization of our practices through accreditation remains a priority, we along with others face challenges with regard to sustainability. Purposeful changes in our consent process, which we term "progressive consent," are expected to improve sustainability and operational flexibility while increasing our scientific impact. Until 2015, informed consent was performed primarily by biorepository staff at an estimated time of 1 hour per case. After a process improvement exercise, we successfully changed our informed consent process to a modified front-door model, with use of material and data for research as an opt-in or opt-out selection on the institutional patient informed consent form provided to surgery patients in the healthcare system. Successful implementation of this change required the engagement and participation of multiple stakeholders in healthcare system leadership, hospital administration, research, legal, regulatory, and patient care levels. A modified front-door consent enabled us to collect an additional 38 specimens in the first two quarters of 2016, with a time commitment of 15.75 hours, a time savings per specimen increasing in Q2 over Q1. We estimate a potential savings of 43 hours in 2016. This progressive model allowed us to maintain our frozen sample collection while increasing the availability of paraffin-embedded tissue and bodily fluids. Augmenting our tissue collection added little expense per case (approximately half that of each frozen tissue aliquot) and increased the range of biospecimens collected. Biorepository financial sustainability is a critical issue. Thorough evaluation and modification of existing procedures and collection models, as well as cost recovery initiatives, can translate into savings. Sustainability, process improvement, and scientific impact broadly overlap and continue to require operational critique and implementation of strategic changes.

Direct Detection and Identification of Bacterial Pathogens from Urine with Optimized Specimen Processing and Enhanced Testing Algorithm

PubMed Central

Huang, Bin; Zhang, Lei; Zhang, Weizheng; Liao, Kang; Zhang, Shihong; Zhang, Zhiquan; Ma, Xingyan; Chen, Jialong; Zhang, Xiuhong; Qu, Pinghua; Wu, Shangwei

2017-01-01

ABSTRACT Rapid and accurate detection and identification of microbial pathogens causing urinary tract infections allow prompt and specific treatment. We optimized specimen processing to maximize the limit of detection (LOD) by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) and evaluated the capacity of combination of MALDI-TOF MS and urine analysis (UA) for direct detection and identification of bacterial pathogens from urine samples. The optimal volumes of processed urine, formic acid/acetonitrile, and supernatant spotted onto the target plate were 15 ml, 3 μl, and 3 μl, respectively, yielding a LOD of 1.0 × 105 CFU/ml. Among a total of 1,167 urine specimens collected from three hospital centers, 612 (52.4%) and 351 (30.1%) were, respectively, positive by UA and urine culture. Compared with a reference method comprised of urine culture and 16S rRNA gene sequencing, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MALDI-TOF MS alone and MALDI-TOF MS coupled with UA were 86.6% versus 93.4% (χ2 = 8.93; P < 0.01), 91.5% versus 96.3% (χ2 = 7.06; P < 0.01), 81.5% versus 96.4% (χ2 = 37.32; P < 0.01), and 94.1% versus 93.1% (χ2 = 0.40; P > 0.05), respectively. No significant performance differences were revealed among the three sites, while specificity and NPV of MALDI-TOF MS for males were significantly higher than those for females (specificity, 94.3% versus 77.3%, χ2 = 44.90, P < 0.01; NPV, 95.5% versus 86.1%, χ2 = 18.85, P < 0.01). Our results indicated that the optimization of specimen processing significantly enhanced analytical sensitivity and that the combination of UA and MALDI-TOF MS provided an accurate and rapid detection and identification of bacterial pathogens directly from urine. PMID:28249997

Direct Detection and Identification of Bacterial Pathogens from Urine with Optimized Specimen Processing and Enhanced Testing Algorithm.

PubMed

Huang, Bin; Zhang, Lei; Zhang, Weizheng; Liao, Kang; Zhang, Shihong; Zhang, Zhiquan; Ma, Xingyan; Chen, Jialong; Zhang, Xiuhong; Qu, Pinghua; Wu, Shangwei; Chen, Cha; Tang, Yi-Wei

2017-05-01

Rapid and accurate detection and identification of microbial pathogens causing urinary tract infections allow prompt and specific treatment. We optimized specimen processing to maximize the limit of detection (LOD) by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and evaluated the capacity of combination of MALDI-TOF MS and urine analysis (UA) for direct detection and identification of bacterial pathogens from urine samples. The optimal volumes of processed urine, formic acid/acetonitrile, and supernatant spotted onto the target plate were 15 ml, 3 μl, and 3 μl, respectively, yielding a LOD of 1.0 × 10 5 CFU/ml. Among a total of 1,167 urine specimens collected from three hospital centers, 612 (52.4%) and 351 (30.1%) were, respectively, positive by UA and urine culture. Compared with a reference method comprised of urine culture and 16S rRNA gene sequencing, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MALDI-TOF MS alone and MALDI-TOF MS coupled with UA were 86.6% versus 93.4% (χ 2 = 8.93; P < 0.01), 91.5% versus 96.3% (χ 2 = 7.06; P < 0.01), 81.5% versus 96.4% (χ 2 = 37.32; P < 0.01), and 94.1% versus 93.1% (χ 2 = 0.40; P > 0.05), respectively. No significant performance differences were revealed among the three sites, while specificity and NPV of MALDI-TOF MS for males were significantly higher than those for females (specificity, 94.3% versus 77.3%, χ 2 = 44.90, P < 0.01; NPV, 95.5% versus 86.1%, χ 2 = 18.85, P < 0.01). Our results indicated that the optimization of specimen processing significantly enhanced analytical sensitivity and that the combination of UA and MALDI-TOF MS provided an accurate and rapid detection and identification of bacterial pathogens directly from urine. Copyright © 2017 American Society for Microbiology.

Preparation of titanium dioxide films on etched aluminum foil by vacuum infiltration and anodizing

NASA Astrophysics Data System (ADS)

Xiang, Lian; Park, Sang-Shik

2016-12-01

Al2O3-TiO2 (Al-Ti) composite oxide films are a promising dielectric material for future use in capacitors. In this study, TiO2 films were prepared on etched Al foils by vacuum infiltration. TiO2 films prepared using a sol-gel process were annealed at various temperatures (450, 500, and 550 °C) for different time durations (10, 30, and 60 min) for 4 cycles, and then anodized at 100 V. The specimens were characterized using X-ray diffraction, field emission scanning electron microscopy, and field emission transmission electron microscopy. The results show that the tunnels of the specimens feature a multi-layer structure consisting of an Al2O3 outer layer, an Al-Ti composite oxide middle layer, and an aluminum hydrate inner layer. The electrical properties of the specimens, such as the withstanding voltage and specific capacitance, were also measured. Compared to specimens without TiO2 coating, the specific capacitances of the TiO2-coated specimens are increased. The specific capacitance of the anode Al foil with TiO2 coating increased by 42% compared to that of a specimen without TiO2 coating when annealed at 550 °C for 10 min. These composite oxide films could enhance the specific capacitance of anode Al foils used in dielectric materials.

Fracture Toughness Determination of Cracked Chevron Notched Brazilian Disc Rock Specimen via Griffith Energy Criterion Incorporating Realistic Fracture Profiles

NASA Astrophysics Data System (ADS)

Xu, Yuan; Dai, Feng; Zhao, Tao; Xu, Nu-wen; Liu, Yi

2016-08-01

The cracked chevron notched Brazilian disc (CCNBD) specimen has been suggested by the International Society for Rock Mechanics to measure the mode I fracture toughness of rocks, and has been widely adopted in laboratory tests. Nevertheless, a certain discrepancy has been observed in results when compared with those derived from methods using straight through cracked specimens, which might be due to the fact that the fracture profiles of rock specimens cannot match the straight through crack front as assumed in the measuring principle. In this study, the progressive fracturing of the CCNBD specimen is numerically investigated using the discrete element method (DEM), aiming to evaluate the impact of the realistic cracking profiles on the mode I fracture toughness measurements. The obtained results validate the curved fracture fronts throughout the fracture process, as reported in the literature. The fracture toughness is subsequently determined via the proposed G-method originated from Griffith's energy theory, in which the evolution of the realistic fracture profile as well as the accumulated fracture energy is quantified by DEM simulation. A comparison between the numerical tests and the experimental results derived from both the CCNBD and the semi-circular bend (SCB) specimens verifies that the G-method incorporating realistic fracture profiles can contribute to narrowing down the gap between the fracture toughness values measured via the CCNBD and the SCB method.

Influence of corn steep liquor and glucose on colonization of control and CCB (Cu/Cr/B)-treated wood by brown rot fungi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humar, Miha; Amartey, Sam A.; Pohleven, Franc

2006-07-01

There are increasing problems with regard to the disposal of treated wood waste. Due to heavy metals or arsenic in impregnated wood waste, burning and landfill disposal options are not considered to be environmentally friendly solutions for dealing with this problem. Extraction of the heavy metals and recycling of the preservatives from the wood waste is a much more promising and environmentally friendly solution. In order to study the scale up of this process, copper/chromium/boron-treated wood specimens were exposed to copper tolerant (Antrodia vaillantii and Leucogyrophana pinastri) and copper sensitive wood decay fungi (Gloeophyllum trabeum and Poria monticola). Afterwards, themore » ability of fungal hyphae to penetrate and overgrow the wood specimens was investigated. The fungal growths were stimulated by immersing the specimens into aqueous solution of glucose or corn steep liquor prior to exposure to the fungi. The fastest colonization of the impregnated wood was by the copper tolerant A. vaillantii. Addition of glucose onto the surface of the wood specimens increased the fungi colonization of the specimens; however, immersion of the specimens into the solution of corn steep liquor did not have the same positive influence. These results are important in elucidating copper toxicity in wood decay fungi and for using these fungi for bioremediation of treated wood wastes.« less

Cohesive Laws for Analyzing Through-Crack Propagation in Cross Ply Laminates

NASA Technical Reports Server (NTRS)

Bergan, Andrew C.; Davila, Carlos G.

2015-01-01

The laminate cohesive approach (LCA) is a methodology for the experimental characterization of cohesive through-the-thickness damage propagation in fiber-reinforced polymer matrix composites. LCA has several advantages over other existing approaches for cohesive law characterization, including: visual measurements of crack length are not required, structural effects are accounted for, and LCA can be applied when the specimen is too small to achieve steady-state fracture. In this work, the applicability of this method is investigated for two material systems: IM7/8552, a conventional prepreg, and AS4/VRM34, a non-crimp fabric cured using an out-of-autoclave process. The compact tension specimen configuration is used to propagate stable Mode I damage. Trilinear cohesive laws are characterized using the fracture toughness and the notch tip opening displacement. Test results are compared for the IM7/8552 specimens with notches machined by waterjet and by wire slurry saw. It is shown that the test results are nearly identical for both notch tip preparations methods, indicating that significant specimen preparation time and cost savings can be realized by using the waterjet to notch the specimen instead of the wire slurry saw. The accuracy of the cohesive laws characterized herein are assessed by reproducing the structural response of the test specimens using computational methods. The applicability of the characterization procedure for inferring lamina fracture toughness is also discussed.