Is there any place for a wait-and-see policy in stage I0 follicular lymphoma? A study of 43 consecutive patients in a single center

BACKGROUND: A wait-and-see policy (WS) does not appear to modify the long-term prognosis of advanced-stage follicular lymphomas (FL), while irradiation of limited stages sometimes causes complications and does not avert distant relapses. Consequently, we decided to test WS in a selected subset of the localized FL, i.e., patients in complete remission (CR) after the initial lymph node biopsy (stage I0). PATIENTS AND METHODS: Forty-three previously untreated patients were diagnosed with stage I0 FL and 26 of them were included in the WS. Their median age was 60.3 years; 19 were male and 24 female. All histological slides were reviewed and confirmed the diagnosis of FL. Median follow-up was 6.3 years (y). RESULTS: Thirteen of the 26 untreated patients are still relapse-free, while six relapsed locally only (median: 4.2 years after diagnosis), and reattained CR with radiotherapy. Seven patients relapsed at distant sites (median: 1 year after diagnosis). No localized relapses were observed in the treated group, but there were 7 distant relapses. CONCLUSIONS: The use of WS in stage I0 FL did not appear to modify the prognosis of these patients. Furthermore, we observed two distinct patterns of relapse (local and distant) that are difficult to differentiate at onset.     

Modification of Vogel's Inflow Performance Relationship (IPR) for Dual Porosity Model

The performance of a solution gas-drive reservoir can be predicted using Vogel inflow performance relation (or IPR), which simply relates the deliverability of a well to bottom-hole pressure and average reservoir pressure. While many studies have shown the success of Vogel-type IPR for single porosity reservoirs, the applicability of this method for naturally fractured reservoirs (NFRs), is under question mainly because of the complex flow behavior in matrix and fracture systems. The present study is undertaken to determine if the relation between NFR flowing wellbore pressure and oil production rate could be described by Vogel's IPR. For this purpose, a synthetic dual porosity fractured reservoir with typical rock and fluid properties is considered as a base-case. Identifying important parameters affecting the performance of a naturally fracture reservoir, a total of 22 simulations covering a wide range of reservoir fluid properties, fracture permeabilities, capillary pressure, block height, and recovery factor are made. The results show significant errors between simulation output and Vogel's IPR. A modification is made on Vogel's IPR to use it for performance prediction of dual porosity model.     

Enhancement of piezoelectric vibration energy harvesting with auxetic boosters

This paper proposes a new concept to enhance the efficiency of the vibration energy harvesting via an intermediate booster. The boosters have auxetic structures and exert extra stretching strain in two perpendicular directions. The concept is tested on a conventional cantilever beam under the base excitation. The problem consists of a cantilever beam subjected to a body load at low frequencies. An auxetic substrate is bonded to the beam with a thin epoxy layer, and the piezoelectric (PZT) element is attached on top of it. Two different auxetic structures are investigated in this study. It is shown that employing these kinds of boosters can remarkably enhance the performance of the energy harvesting system. The harvesting efficiency is numerically evaluated in different load amplitudes and frequencies. A parametric study is then carried out, and effects of different geometrical design parameters of the auxetic boosters on the performance of the energy harvesting system are investigated. Comparing with the case in which the PZT is straightly attached to the cantilever, it is shown that adding such intermediate boosters at low-frequency range can increase the extracted power by factors of 3.9 and 7.0 for the two proposed geometries.     

Kinetics and critical conditions for initiation of dynamic recrystallization during hot compression deformation of AISI 321 austenitic stainless steel

Dynamic recrystallization behavior of AISI 321 austenitic stainless steel were studied using hot compression tests over the range of temperatures from 900 °C to 1200 °C and strain rates from 0.001 s^-1 to 1 s^-1. The critical strain and stress for initiation of dynamic recrystallization were determined by plotting strain hardening rate vs. stress curves and a constitutive equation describing the flow stress at strains lower than peak strain. Also, the strain at maximum flow softening was obtained and the effect of deformation conditions (Z parameter) on the critical strain and stress were analyzed. Finally, the volume fraction of dynamic recrystallization was calculated at different deformation conditions using these critical values. Results showed that the model used for predicting the kinetics of dynamic recrystallization has a great consistency with the data, in the form of θ-ε curves, directly acquired from experimental flow curves.     

Image enhancement using a high sequency ordered hadamard transform filtering (HSHTF)

The enhancement of image where the picture contains additive noise is considered. The procedure of high sequency ordered Hadamard transform filtering HSHTF is utilized to recursively improve the enhancement of the image. In each step the average error between reconstructed and original image is determined. The HSHTF was implemented to a generalized two dimensional Weiner filter to improve the quality of the reconstructed image. Examples are used to illustrate the effectiveness of the procedure.     

Inlay-inspired meta-piezoelectric plates for the low-frequency vibration energy harvesting

Journal of Materials Science: Materials in Electronics - Different novel auxetic geometries are proposed applicable for the low-frequency vibration energy harvesting. The geometrical idea...     

Effect of Hot Torsion Parameters on Development of Ultrafine Ferrite Grains in Microalloyed Steel

 Hot torsion testing was performed on a low carbon Nb-Ti microalloyed steel to study the effects of hot torsion parameters, strain and strain rate, on ultrafine ferrite grains production through dynamic strain-induced transformation, at a deformation temperature just above Ar3. The initiation and evolution of ultrafine ferrite grains were studied. The results show that the amount of strain and strain rate has conversely effect on the volume fraction and grain size of ultrafine ferrite grains. With increasing strain, the interior of austenite grains become activated as nucleation sites for fine ferrite grains. As a result, ferrite grains continuously nucleate not only at the former austenite grain boundaries but also inside the austenite grains which leads to a rapid increase in volume fraction of ultrafine grains. Increasing of strain rate reduces the tendency of ferrite grains coarsening so that ultrafine ferrite grains are achieved, while the volume fraction of ultrafine grains decreases at the same strain level.     

Effect of Strain Rate on the Ferrite Grain Refinement in a Low Carbon Nb-Ti Microalloyed Steel during Low Temperature Deformation

1. IntroductionThe thermomechanical controlled processing(TMCP) of microalloyed steels has been employed fosome times in the production of plates and sheet material to optimize mechanical properties. The centrafeature of thermomechanically processed steel is the ul-trafine grain size in the final product. Therefore, theferrite grain refinement of structural steels has attractedconsiderable interest from engineering scientists due toits unique role of increasing both strength and toughnessDem…     

Exploring the possibilities of cryogenic cooling in liquid chromatography for biological applications: a proof of principle

The possibilities to use cryogenic cooling to trap components in liquid chromatography was investigated. In a first step, van 't Hoff plots were measured with a reversed-phase column using the temperature control unit of a conventional high performance liquid chromatography (HPLC) system to gain insight in the retention behavior of proteins at low temperatures. It was estimated that retention factors in the range of k = 10(4) could be achieved at T = -20 °C for lysozyme, indicating that temperature is a usable parameter to trap components in LC. In a next step, trapping experiments were carried out on a nano-LC system, equipped with a UV-detector, using a commercial reversed-phase column. An in-house built setup, allowing cooling of a segment of the column down to temperatures below T = -20 °C, was used to trap components. Experiments were conducted under isocratic and gradient conditions with methanol as organic solvent. It is demonstrated that, by thermally trapping and elution of components, an enhanced S/N ratio and decreased peak widths can be obtained. At the same time, a significant increase in pressure drop occurs during the cooling process. Limitations and benefits of the technique are further discussed.     

Characterization of Austenite Dynamic Recrystallization under Different Z Parameters in a Microalloyed Steel

A low carbon Nb-Ti microalloyed steel was subjected to hot torsion testing over the temperature range 850-1100℃ and strain rates 0.01-1s-1 to study the influence of deformation conditions on the dynamic recrystallization characteristics of austenite.The results show that dynamic recrystallization occurs more easily with the decrease of strain rate and the increase of deformation temperature.The complete dynamically recrystallized grain size as a function of Zener-Hollomon parameter was established.It was found that dynamically recrystallized grain sizes decrease with increasing strain rate and decreasing deformation temperature.The effect of microalloying elements on peak strain was investigated and the solute drag corrected peak strain was determined.Also,the dynamic recrystallization map of austenite was obtained by using recrystallization critical parameters.