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Objective To explore the application value of mpMRI-TRUS multi-modal image fusion transperineal biopsy technique using electromagnetic needle tracking under local anesthesia combined with rapid paraffin-embedded section of small specimen in the diagnosis of prostate cancer. Methods The clinicopathological data of 138 patients with PI-RADS score≥3 who underwent mpMRI-TRUS image fusion transperineal biopsy using electromagnetic needle tracking under local anesthesia were retrospectively analyzed. AI technology was used to fuse mpMRI and TRUS multi-mode images, and two-core targeted biopsies were performed on suspicious lesions, followed by 12-core systematic biopsies. The specimens obtained from targeted biopsies were sent for rapid paraffin-embedded section pathological examination, and the detection rates of csPCa were compared. Results The detection rate of csPCa in 138 patients was 71.01%. The detection rates of csPCa in targeted biopsies and systematic biopsies were 62.32% and 70.29%, respectively (P=0.20). The detection rate of combined biopsies was higher than those of targeted biopsies and systematic biopsies, but the difference was not statistically significant (P>0.05). The detection rates of csPCa in targeted biopsies, systematic biopsies, and combined biopsies in patients with PI-RADS score 3 were 30.95%, 38.10%, and 40.48%, respectively; and the percentages were 52.94%, 61.76%, and 61.76% in patients with PI-RADS score 4, respectively; and the percentages were 90.32%, 96.77%, and 96.77% in patients with PI-RADS score 5, respectively, without statistically significant difference (all P>0.05). In the subgroups with PI-RADS scores of 3, 4, and 5, the missed diagnosis rates of csPCa by targeted biopsies were 23.53%, 14.29%, and 6.67%, respectively. Conclusion For patients with suspected prostate cancer and PIRADS v2.1 score≥3, transperineal biopsy using electromagnetic needle tracking combined with rapid paraffin-embedded section of small specimen can obtain pathological results rapidly and has good diagnostic accuracy. However, combined biopsy is still the most suitable method for the diagnosis of prostate cancer at present. [ABSTRACT FROM AUTHOR]

ObjectiveTo explore the application value of mpMRI-TRUS multi-modal image fusion transperineal biopsy technique using electromagnetic needle tracking under local anesthesia combined with rapid paraffin-embedded section of small specimen in the diagnosis of prostate cancer. MethodsThe clinicopathological data of 138 patients with PI-RADS score≥3 who underwent mpMRI-TRUS image fusion transperineal biopsy using electromagnetic needle tracking under local anesthesia were retrospectively analyzed. AI technology was used to fuse mpMRI and TRUS multi-mode images, and two-core targeted biopsies were performed on suspicious lesions, followed by 12-core systematic biopsies. The specimens obtained from targeted biopsies were sent for rapid paraffin-embedded section pathological examination, and the detection rates of csPCa were compared. ResultsThe detection rate of csPCa in 138 patients was 71.01%. The detection rates of csPCa in targeted biopsies and systematic biopsies were 62.32% and 70.29%, respectively (P=0.20). The detection rate of combined biopsies was higher than those of targeted biopsies and systematic biopsies, but the difference was not statistically significant (P>0.05). The detection rates of csPCa in targeted biopsies, systematic biopsies, and combined biopsies in patients with PI-RADS score 3 were 30.95%, 38.10%, and 40.48%, respectively; and the percentages were 52.94%, 61.76%, and 61.76% in patients with PI-RADS score 4, respectively; and the percentages were 90.32%, 96.77%, and 96.77% in patients with PI-RADS score 5, respectively, without statistically significant difference (all P>0.05). In the subgroups with PI-RADS scores of 3, 4, and 5, the missed diagnosis rates of csPCa by targeted biopsies were 23.53%, 14.29%, and 6.67%, respectively. ConclusionFor patients with suspected prostate cancer and PI-RADS v2.1 score≥3, transperineal biopsy using electromagnetic needle tracking combined with rapid paraffin-embedded section of small specimen can obtain pathological results rapidly and has good diagnostic accuracy. However, combined biopsy is still the most suitable method for the diagnosis of prostate cancer at present.

Two stress regime‐dependent creep constitutive equations, that is, two‐regime Norton (2RN) model and Sin‐hyperbolic (Sinh) model, are adopted to numerically investigate the influence of constitutive equation and friction on the measurement of steady‐state creep strain rate based on five types small specimens. Results show that the influence of constitutive equation and friction depends strongly on the type of small specimen. A measurement error of more than 19 times may occur if the 2RN model is used, while the use of the Sinh model is able to generate a consistently lower measurement error. Of all small specimens, the cantilever beam testing (CaBT) is revealed to exhibit the best comprehensive performance in terms of measurement error and response to friction. To validate numerical findings, creep tests on the CaBT specimen of P91 steel are conducted at 600°C. Finally, recommendations on the choice of small specimen for obtaining creep strain rate are made. Highlights: Sinh model is better in describing stress regime‐dependent creep behavior.Influence of friction is strongly dependent on the type of small specimen.Small cantilever beam testing has the best comprehensive performance.Attention should be paid to selecting the constitutive equation and specimen type. [ABSTRACT FROM AUTHOR]

During reassessment of an existing steel structure, the designer is often confronted with the fact that the current design loads exceed the loads considered in the original design. Furthermore, fatigue damage may exist that needs to be accounted for in the assessment of the future design life. A possible approach in such a case is to use the actual values of fy and fu, because these commonly exceed the nominal values by a considerable margin. For a fatigue assessment by means of a crack growth analysis, fracture toughness properties are required which are usually not well documented, especially for older structures. To obtain specimens to determine the material properties by standardized material tests, a sizable quantity of material needs to be removed from the structure at the critical location where the design loads exceed the resistance, which is undesirable. This paper presents material testing methods using small specimens, for which only a small quantity of material is needed. The material is extracted by drilling a M39 bolt hole, which has a limited influence on the static resistance of the structure. Furthermore, a high fatigue detail category can be attained by applying a preloaded bolt. Tensile tests are performed on the removed material which give equivalent results to the current standardized tests. Fracture toughness tests are also performed, again with similar results as commonly used standardized tests. Validation of the test methods is shown through comparison with standardized tests. [ABSTRACT FROM AUTHOR]

Abstract Background Successful practice of precision medicine in advanced lung cancers relies on therapeutic regimens tailored to individual molecular characteristics. The aim of this study was to investigate the accuracy of small specimens for molecular profiling using next-generation sequencing (NGS). Methods Genetic alternations, tumor mutational burden (TMB), status of microsatellite instability (MSI), and expression of programmed death ligand 1 (PD-L1) were compared side-by-side between the concurrently obtained core needle biopsy (CNB) and resection specimens in 17 patients with resectable non-small cell lung cancers. Results DNA yield and library complexity were significantly lower in CNB specimens (both p < 0.01), whereas the insert size, sequencing depth, and Q30 ratio were similar between the matched specimens (all p > 0.05). The total numbers of genetic alternations detected in resection and CNB specimens were 186 and 211, respectively, with 156 alternations in common, yielding a specific concordance rate of 83.9%. The prevalence of mutations in 8 major driver genes was 100% identical between surgical and CNB specimens, though the allele frequency was lower in CNB specimens, with a median underestimation of 57%. Results of TMB were similar (p = 0.547) and MSI status was 100% matched in all paired specimens. Conclusions Pulmonary CNB specimens were suitable for NGS given the satisfactory accuracy when compared to corresponding surgical specimens. NGS results yielding from CNB specimens should be deemed reliable to provide instructive information for the treatment of advanced lung cancers.

Background: Successful practice of precision medicine in advanced lung cancers relies on therapeutic regimens tailored to individual molecular characteristics. The aim of this study was to investigate the accuracy of small specimens for molecular profiling using next-generation sequencing (NGS). Methods: Genetic alternations, tumor mutational burden (TMB), status of microsatellite instability (MSI), and expression of programmed death ligand 1 (PD-L1) were compared side-by-side between the concurrently obtained core needle biopsy (CNB) and resection specimens in 17 patients with resectable non-small cell lung cancers. Results: DNA yield and library complexity were significantly lower in CNB specimens (both p < 0.01), whereas the insert size, sequencing depth, and Q30 ratio were similar between the matched specimens (all p > 0.05). The total numbers of genetic alternations detected in resection and CNB specimens were 186 and 211, respectively, with 156 alternations in common, yielding a specific concordance rate of 83.9%. The prevalence of mutations in 8 major driver genes was 100% identical between surgical and CNB specimens, though the allele frequency was lower in CNB specimens, with a median underestimation of 57%. Results of TMB were similar (p = 0.547) and MSI status was 100% matched in all paired specimens. Conclusions: Pulmonary CNB specimens were suitable for NGS given the satisfactory accuracy when compared to corresponding surgical specimens. NGS results yielding from CNB specimens should be deemed reliable to provide instructive information for the treatment of advanced lung cancers. [ABSTRACT FROM AUTHOR]

• Obtain certain fracture toughness data by combining finite element simulation and actual experiments. • Training BP neural network to predict the fracture toughness of standard specimens. • Verified the mapping relationship between fracture toughness data of small-sized specimens and standard specimens. • Compared the prediction accuracy with the Beremin model. In this study, a neural network was used to predict the fracture toughness of standard specimens of 16MnDR steel in the tough-brittle transition zone. The main factors such as specimen plate thickness and geometry type are taken as inputs to the network and the fracture toughness of the standard specimen is taken as output. A BP neural network is utilized to describe the nonlinear relationship between them. The network was trained and tested by using finite element simulation simulation data based on experimental data. The established neural network model was found to have good accuracy in predicting the experimental data and can be used as a method for predicting the fracture toughness of 16MnDR standard specimens. [ABSTRACT FROM AUTHOR]

Small specimen mechanical testing is an exciting and rapidly developing field in which fundamental deformation behaviours can be observed from experiments performed on comparatively small amounts of material. These methods are particularly useful when there is limited source material to facilitate a sufficient number of standard specimen tests, if any at all. Such situations include the development of new materials or when performing routine maintenance/inspection studies of in-service components, requiring that material conditions are updated with service exposure. The potentially more challenging loading conditions and complex stress states experienced by small specimens, in comparison with standard specimen geometries, has led to a tendency for these methods to be used in ranking studies rather than for fundamental material parameter determination. Classifying a specimen as 'small' can be subjective, and in the present work the focus is to review testing methods that utilise specimens with characteristic dimensions of less than 50 mm. By doing this, observations made here will be relevant to industrial service monitoring problems, wherein small samples of material are extracted and tested from operational components in such a way that structural integrity is not compromised. Whilst recently the majority of small specimen test techniques development have focused on the determination of creep behaviour/properties as well as sub-size tensile testing, attention is given here to small specimen testing methods for determining specific tensile, fatigue, fracture and crack growth properties. These areas are currently underrepresented in published reviews. The suitability of specimens and methods is discussed here, along with associated advantages and disadvantages. [ABSTRACT FROM AUTHOR]

Research on fluctuations in energy and temperature is presented for a small specimen. The small specimen in contact with a heat bath shows energy fluctuations, Δ E , at the constant temperature. On the other hand, when this small specimen is isolated from the reservoir and adiabatic isolation is kept, it exhibits temperature fluctuations, Δ T , at the constant energy. This means that the temperature is unsharp if a sharp energy is assigned. A complementary relation between Δ E and Δ T is proposed in a simple formula. The connection between Δ E and Δ T is mediated by the heat capacity C V (T). This complementary relation is valid in general and it does not depend on the amount of substance. If the constituent number N of the system is of the order of Avogadro's number, then the fluctuations have been masked by large N and we cannot see the influence of the fluctuations. However, when the number N decreases, the intrinsic features of fluctuations come out gradually. This paper presents the quantitative analyses of the fluctuations in the energy and temperature for several physical models. Typical characteristics in the fluctuations can be clearly seen only in a small specimen, which are shown in the graphical representations. It is stressed that the values of Δ E and Δ T are defined for the different prescribed conditions specified above. [ABSTRACT FROM AUTHOR]

Emphasis on the use of small specimens for biomarker testing to provide prognostic and predictive information for guiding clinical management for patients with advanced-stage cancer has been increasing. These biomarker tests include molecular analysis, cytogenetic tests, and immunohistochemical assays. Owing to the limited nature of the cellular material procured in these small specimens, which are collected using minimally invasive techniques (ie, fine needle aspiration and core needle biopsy), pathologists have been required to triage these samples judiciously and provide the clinically relevant genomic information required for patient care. Awareness of the advantages and limitations of these specimen preparations and the specific preanalytic requirements for the testing methods will help pathologists to develop optimal strategies to maximize the chances of effectively using these samples for comprehensive diagnostic and relevant biomarker testing. • Small specimens are increasingly used for biomarker testing to provide prognostic and predictive information. • Specimens concurrently acquired from core needle biopsy and fine needle aspiration procedures are frequently complementary and are often used in conjunction as a single "small specimen" for biomarker testing. • Pathologists are tasked with triaging these samples judiciously and providing the clinically relevant genomic information needed for patient care. • Being aware of specific pre-analytic requirements for the testing methodologies can help the pathologist develop optimal strategies to maximize effective utilization of these samples for comprehensive diagnostic and relevant biomarker testing. [ABSTRACT FROM AUTHOR]

Background: Cell blocks represent one of several cytology preparations, and play a significant role in providing tissue for ancillary studies, including immunohistochemistry and molecular testing. To the authors' knowledge, there currently is no standardized cell block processing method, and cellular yield often is suboptimal. To overcome the shortcomings of available methods, the authors developed a novel disposable cell block device, XCellent, that uses centrifugation to collect cells into a sample chamber. The sample chamber contains and protects the specimen during tissue processing and also is embedded and sectioned. The primary objectives of the current study were to compare cellular yield, cytomorphological detail, and processing times of HistoGel and XCellent. Methods: Split sample testing of primarily fluid specimens was performed. Group 1 comprised large‐volume and/or cloudy fluids and group 2 was residual samples in PreservCyt solution. Two cell blocks, 1 HistoGel cell block and 1 XCellent cell block, were processed from each sample. Cellularity was assessed using computerized image analysis and cytomorphology from 1+ to 3+. Processing times for 16 cell blocks also were recorded. Results: A total of 50 cell blocks (25 HistoGel samples and 25 XCellent samples) were prepared. On average, cell blocks prepared using XCellent were 371% more cellular than those prepared with HistoGel and had better cytomorphology. Less preparation time was required for bulk processing of XCellent cell blocks (11 minutes) compared with the same quantity of bulk processed using HistoGel (38 minutes). Conclusions: XCellent provides an alternative cell block processing technique that offers high cellular yield and cytomorphology. In addition, the method uses the standard centrifugation process, which integrates into the existing cytology laboratory workflow. There currently is no standardized cell block processing method, and cellular yield often is suboptimal. To overcome the shortcomings of available methods, the authors have developed a novel disposable cell block device, XCellent, that uses centrifugation to collect cells into a sample chamber. XCellent provides enhanced cellularity, cytomorphology, and efficiency compared with the HistoGel method. [ABSTRACT FROM AUTHOR]

Fatigue life assessment considering neutron irradiation effects is necessary for fusion reactor. However, the fatigue life data for neutron-irradiated materials are very limited. Therefore, the prediction of the fatigue life of irradiated materials is expected. Prediction of fatigue life using the universal slope equation developed by Manson has been focused. In this work, the prediction accuracy and feasibility of utilizing small specimen for fatigue life prediction were investigated for non-irradiated reduced activation ferritic/martensitic steels (i.e. F82H-IEA, F82H-BA07 and JLF-1). The prediction accuracies for F82H-BA07 and JLF-1 were acceptably irrespective of test temperature (mostly within a factor of 2). In contrast, non-negligible errors were observed for F82H-IEA (mostly exceeding a factor of 2), which increased with the test temperature. The prediction errors for F82H-IEA might be attributed to its unexpected plastic behavior, which was not considered in the universal slope equations. The SS-J small tensile specimen showed no disadvantageous prediction accuracy regardless of the prediction equation, material, fatigue life range, or test temperature range. Therefore, the SS-J specimen could be utilized for fatigue life prediction by the universal slope equations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The gauge length and width have more influence on the fatigue life than the thickness when specimen sizes are reduced. • The GBDT algorithm could predict fatigue life more accurately. • The GBDT algorithm is reliable for life prediction of thinner specimen and other materials. In this paper, both experimental and machine learning results show that the fatigue life of A588 steel specimens with different gauge lengths and widths varies more greatly compared with that of the specimens with different thicknesses as the gauge dimensions are reduced from 15 mm to 1.5 mm. The optimal machine learning algorithm is derived to predict the fatigue life of specimens with a thickness of 1 mm, and the predicted results are verified by the fatigue experiments. [ABSTRACT FROM AUTHOR]

The method of crack growth rate measurement in miniature single edge notched (SEN) cantilever specimen at stress ratio R ∼ −1 is presented. The resonance circuit is formed by the cantilever specimen with inertial yoke at its free end excited by alternating electromagnetic field. The parameters of the harmonic excitation are controlled by the phase shift technique. The crack length is estimated from specimen compliance added by the crack opening. The stress intensity factor is computed from the applied bending moment. Linear elastic fracture mechanics with standard shape functions corresponding to the particular specimen geometry and applied loading are used. The analysis of signal from single piezoelectric accelerometer provides data for the estimation of crack length and applied stress intensity factor, making the method very simple and inexpensive, yet reasonably accurate. The crack length measurement was calibrated using fractographic marking technique. The presented method was validated by performing crack growth rate tests in miniature 4 × 3 × 32 mm beam specimens with 150° chevron notch. 7075 aluminium alloy and 4043 high strength steel were tested at load frequency of 110 and 160 Hz respectively. The crack growth curves were measured in both load increase and load reduction mode and the resulting crack compare well with the baseline data available for standard central crack (CCT) specimens. [ABSTRACT FROM AUTHOR]

The hydraulic bulge test (HBT) method is proposed to determine material tensile strengths. The basic idea of HBT is similar to the small punch test (SPT), but inspired by the manufacturing process of rupture discs-high-pressure hydraulic oil is used instead of punch to cause specimen deformation. Compared with SPT method, the HBT method can avoid some of influence factors, such as punch dimension, punch material, and the friction between punch and specimen. A calculation procedure that is entirely based on theoretical derivation is proposed for estimate yield strength and ultimate tensile strength. Both conventional tensile tests and hydraulic bulge tests were carried out for several ferrous alloys, and the results showed that hydraulic bulge test results are reliable and accurate. [ABSTRACT FROM AUTHOR]

In this study, a new fatigue testing method under shear and axial loading was developed for small specimens (3mm long and 0.3mm thick). The method was applied to a single crystal of pure iron and extra-low carbon steel in order to investigate the effect of shear and normal stress on cyclic slip activity. The specimen was sufficiently small to be prepared from a single crystal, aiming at a specific slip system in the shear loading direction. Moreover, the specimen had a single edge notch, which was designed to generate both pure shear stress and normal stress. Using this testing method, shear fatigue strength with a static normal stress on the slip system [111] was evaluated, and the fatigue strength was compared with that of polycrystalline ferrite steel with static axial loading. [ABSTRACT FROM AUTHOR]

The systematically comparison between small punch test and hydraulic bulge test is carried out, which include specimen geometry, the test device, testing procedure, testing results interpretation. The specimen geometry, test device and testing procedure are three major aspects of the experiments. Both the testing fixtures of SPT and HBT are redesigned to meet the specimen geometry. The testing procedure of SPT is similar to strain-controlled tension test, which control the displacement of the puncher and measure the corresponding reaction load. The testing procedure of HBT is similar to stress-controlled tension test, which control the pressure of the hydraulic oil and measure the displacement of the deformed specimen. The finite element method is used to study the deformation pattern of the specimen. The initial plastic zone distribution is different. The plastic zone of SPT is concentrated in a small area under the puncher and the initial plastic zone is a circle around the corner of the fixture for HBT. The deformation pattern play an important role in the yield stress interpretation, it is suggest that the interpretation method should include the parameters from the testing fixtures for HBT, and radius of the puncher for SPT.

The use of small specimens in routine testing would reduce resource requirements, however, limitations exist due to concerns over size effects, manufacturing difficulties, uncertainties related to the application of representative loading conditions, and complex interpretation procedures of non-standard data. Due to these limitations, small specimen testing techniques have been mostly applied for ranking exercises and to determine approximate or simple material parameters such as Young’s modulus, creep minimum strain rate and fracture toughness. The small ring method is a novel, high sensitivity small specimen technique for creep testing and has been extended in the present work for the determination of tensile material properties. Wrought aluminium alloy 7175-T7153 was tested at room temperature at 5 different loading rates. Finite element analysis was completed to evaluate the equivalent gauge section and equivalent gauge length in order to compare uniaxial tensile testing results and small ring specimen tensile testing results. An analytical solution has also been derived in order to validate the finite element analysis. It was discovered that the finite element analysis model was suitable, validated by both experimental results and analytical solution as well as that small ring specimens can be used to acquire same stress/strain data as uniaxial specimens.

For small-specimen bending creep tests, large deformation occurs inevitably when the specimen under a large load or a long creep time. In such a circumstance, the conventional method for creep property evaluation, which is based on the small deformation assumption, may fail to attain a sufficiently high accuracy. Three typical specimens including circular ring, three-point bending and cantilever-beam specimens, are therefore examined. Based on the limit load approach, a critical load method is proposed to control the large deformation effect. Analytical solutions of the critical loads of the specimens are derived. Finite element method is used to quantitatively assess the effect of large deformation. The results show that the predicted creep curves of all the three specimens are significantly affected by the large deformation. Creep properties can only be accurately regressed when the applied load is below the critical load. The critical loads calculated by finite element method agree well with the analytical solutions. Furthermore, the analytical solutions are validated by the experimental results. The effect of creep time on the critical load has also been discussed. [ABSTRACT FROM AUTHOR]

The hydraulic bulge test (HBT) method is proposed to determine material tensile strengths. The basic idea of HBT is similar to the small punch test (SPT), but inspired by the manufacturing process of rupture discs—high-pressure hydraulic oil is used instead of punch to cause specimen deformation. Compared with SPT method, the HBT method can avoid some of influence factors, such as punch dimension, punch material, and the friction between punch and specimen. A calculation procedure that is entirely based on theoretical derivation is proposed for estimate yield strength and ultimate tensile strength. Both conventional tensile tests and hydraulic bulge tests were carried out for several ferrous alloys, and the results showed that hydraulic bulge test results are reliable and accurate.

A novel method for dynamic testing of small specimens, based on impact loading, is proposed. This is motivated by the desire to elicit the dynamic mechanical response of single solder joints measuring 0.5 mm smaller in size. Impact loading is generated through impact of a tubular striker against a loading plate which is initially in contact with the specimen. The mechanical response of the specimen is derived from noting the stress waves generated in slender bars attached to the loading plate and specimen. Through this approach, dynamic tension or compression can be conveniently applied using the same test apparatus, and exact alignment of the slender bars attached is not critical. In addition, wave dispersion or attenuation in the bars (e.g., when polymer bars are used) has much less influence on the accuracy of results obtained. The equations governing this novel approach are derived and validated by finite element modeling. A prototype of a miniature impact tester was consequently fabricated, and tests on small aluminum specimens showed results comparable to that employing traditional split Hopkinson bar systems. The test arrangement was utilized for dynamic testing of lead-free single solder joint specimens, and initial results obtained are presented. [ABSTRACT FROM AUTHOR]

BACKGROUND Increasingly, minimally invasive procedures are performed to assess lung lesions and stage lung carcinomas. In cases of advanced-stage lung cancer, the biopsy may provide the only diagnostic tissue. The aim of this study was to determine which method-fine-needle aspiration (FNA), core biopsy (CBx), or both (B)-is optimal for providing sufficient tissue for rendering a specific diagnosis and pursuing molecular studies for guiding tumor-specific treatment. METHODS A search was performed for computed tomography-guided lung FNA, CBx, or B cases with rapid onsite evaluation. Carcinomas were assessed for the adequacy to render a specific diagnosis; this was defined as enough refinement to subtype a primary carcinoma or to assess a metastatic origin morphologically and/or immunohistochemically. In cases of primary lung adenocarcinoma, the capability of each modality to yield sufficient tissue for molecular studies (epidermal growth factor receptor, KRAS, or anaplastic lymphoma kinase) was also assessed. RESULTS There were 210 cases, and 134 represented neoplasms, including 115 carcinomas. For carcinomas, a specific diagnosis was reached in 89% of FNA cases (33 of 37), 98% of CBx cases (43 of 44), and 100% of B cases (34 of 34). For primary lung adenocarcinomas, adequate tissue remained to perform molecular studies in 94% of FNA cases (16 of 17), 100% of CBx cases (19 of 19), and 86% of B cases (19 of 22). No statistical difference was found among the modalities for either reaching a specific diagnosis ( p = .07, Fisher exact test) or providing sufficient tissue for molecular studies ( p = .30, Fisher exact test). CONCLUSIONS The results suggest that FNA, CBx, and B are comparable for arriving at a specific diagnosis and having sufficient tissue for molecular studies: they specifically attained the diagnostic and prognostic goals of minimally invasive procedures for lung carcinoma. Cancer (Cancer Cytopathol) 2015;123:318-26. © 2015 American Cancer Society. [ABSTRACT FROM AUTHOR]

Three-point bending creep tests using miniaturized specimen are proposed to assess creep constitutive properties of materials. Based on Norton’s creep law, the analytical model for the three-point bending specimen is given. Through the analytical model, creep parameters can be obtained by regressing the bending test data. Maximum stress approach and reference stress approach are used to convert bending test data to equivalent uniaxial tensile test data. In order to verify these approaches, both three-point bending and uniaxial creep tests of 23CrMoNiWV88 steel are performed. The results show that the derived creep parameters from the bending test data are in reasonable agreement with those obtained from conventional uniaxial creep tests. The equivalent uniaxial creep data converted using reference stress approach are more reasonable than that using maximum stress approach. It has also been found that the large deformation may have a significant influence on the conversion relationship. The results are only accurate at relatively low load levels during testing. [ABSTRACT FROM PUBLISHER]

It is very convenient to evaluate new floating floor constructions by using a small size specimen (< 1 m²) in real building instead of testing the same construction in a laboratory on a big area (≥ 10 m²) specimen (as it is required by the standard). No information has been found in scientific literature about any research in which such small specimens (for example, 0.5 m²) were used. Therefore a question occurred whether such specimens could in fact be used in practice instead of big ones (≥ 10 m²) and if so, under what conditions. In order to answer this question, the first step is to study the previous research. It provides the ΔLW values of small size specimens and how they differ (are smaller) from those of big specimens. As a result of this, a new question has arisen whether the shape (the ratio of the sides of a rectangular specimen) of the specimen does have an influence on the results (ΔLW) or whether only the size of the specimen (area) influences it. In this experiment, the specimen shape was changed from rectangular to square (though maintaining the same specimen's area of about 0.5 m²). The results of the experiment showed that different shapes of a small specimen have negligible influence on ΔLW value. Moreover, the experiment results, which provided some answers to previously mentioned questions, led us to offer evaluation methodology for determination and compensation of ΔLW measurement methodology errors, which are hypothetically independent from physical parameters of floating floor construction components using small area (0.5 m²) specimens. In order to be sure of the correctness of the presented methodology, a reinforcement of further investigation is required. [ABSTRACT FROM AUTHOR]

Small specimen testing techniques are potentially highly useful procedures which could be used to determine many fundamental material properties from relatively small amounts of sample material. Small specimens can be manufactured from scoop samples taken from the surface of a component, allowing for continued operation after sampling. In the past, it has been assumed that, provided the wall thickness dimension around the specimen sample site is greater than the minimum design requirement, the action of scoop sampling will not greatly compromise the future operation of the component. Little study has been completed, however, to verify this assumption or to evaluate the likely reduction in remnant life due to scoop sampling. In the present study, a finite element investigation is made into the effects of scoop sampling on the stress states and failure lives of power plant straight pipes under steady-state creep conditions. Loading conditions considered include an internal pressure load only (assuming closed-end conditions), as well as system loading (in the form of additional axial and in-plane bending moment loading). Typically, the application of system loading increases the likelihood of failure being controlled by the stress states in the vicinity of a scoop excavation. This leads to potentially significant reductions (up to approximately 90%) in creep life of straight piping components. Parametric equations (valid for a range of pipe geometries and scoop cut depths) have been proposed, which can estimate the stress riser effect in the vicinity of an excavation sample under closed-end and additional axial loading conditions. [ABSTRACT FROM PUBLISHER]

Abstract: The present paper highlights the usefulness of impression creep technique as applicable to alloy development studies of a creep resistant austenitic stainless steel which has been used as structural material for Fast Breeder Reactors. The effect of nitrogen on creep deformation behavior of type 316LN stainless steel has been studied using impression creep testing technique. Impression creep tests have been carried out at 923K on 316LN stainless steel containing 0.07, 0.11, 0.14, and 0.22wt. % nitrogen, in the punching stress range of 472-760MPa. The impression creep curves were characterized by a loading strain, a primary creep stage and a secondary creep stage similar to uniaxial creep curves. The tertiary stage observed in uniaxial creep curves was absent. The steady state impression velocity was found to increase with increasing punching stress. It was observed that impression velocity was sensitive to the variation in nitrogen content in the steel. Steady state impression velocity was found to decrease with increasing nitrogen content as was observed in conventional uniaxial creep tests. A good correlation between the impression creep test and the conventional creep test results was observed which demonstrates the applicability of impression creep testing technique for alloy development programme. [Copyright &y& Elsevier]

Interest in and the application of small specimen creep test techniques are increasing. This is because it is only possible to obtain small samples of material in some situations, for example, the scoop samples that are removed from in-service components, the heat-affected zones that are created when welds are used to join components and the desire to produce only small amounts of material in alloy development programmes. It is therefore important to review and compare the theoretical basis and practical aspects of each of the small specimen creep testing methods, in order to clearly understand which of the methods is the best for any specific application. This article provides the theoretical basis for each commonly used test method. [ABSTRACT FROM AUTHOR]