This paper presents a theoretical approach addressing plastic-strain spreading in post-irradiated BCC materials accounting for crucial sub-grain scale, dislocation-mediated plasticity mechanisms. The ...proposed model explicitly provides the number of shear-bands developed in irradiated (Nirr) versus non-irradiated (N00dpa) grain cases, for fixed amounts of plastic deformation. Calculations carried out under various irradiation defect size and number density cases, which helps it appraising important material properties, in particular the dose-dependent, grain-scale uniform elongation threshold. The model ability to handle macro-scale effects is then evaluated using a simple stochastic calculation procedure, taking advantage of actual grain size and orientation maps. The dose-dependent embrittlement amplitude appears to critically depend on the shear band thickness and spacing variations, existing near the fracture surface of failing specimens. That perception allows comparing our predictions with adapted test results, for validation.
Neuromuscular electrical stimulation (NMES) elicits muscle contraction and has been shown to improvement of quality of life. However, if NMES improvement the quality of life and attenuate the ...inflammation is not fully understood. Therefore, our aim sought to assess the effects of short-term of intradialytic NMES on inflammation and quality of life in patients with chronic kidney disease patients undergoing hemodialysis. A randomized clinical trial conducted with parallel design enrolled adult hemodialysis patients three times a week during 1 month. Patients were randomly assigned to two groups (control group, n = 11; 4F/7 M) or (NMES group, n = 10; 4F/6 M). Pre-and post-intervention, was measured the high-sensitivity C reactive protein, interleukin-6, interleukin-10, and TNFα by the ELISA, and quality of life was applied using the SF-36. During each hemodialysis session, NMES was applied bilaterally at thigh and calves for 40 min. There was not change in cytokines (hs-CRP, IL-6, IL-10, and TNFα) concentrations time × group interaction. In addition, no difference was found in eight domains of quality of life. In addition, the groups did not differ for muscle strength and muscle mass. In conclusion, we found that intradialytic NMES did not change inflammation neither quality of life.
Sigma-phase precipitation in a 316Nb “stabilized” austenitic stainless steel was studied through complementary CALPHAD-based and dedicated experimental investigations. Thermokinetic calculations ...performed using Thermo-Calc (with the DICTRA module) and MatCalc software showed that the sigma phase (σ) precipitated directly at γ-austenite grain boundaries (GB) via a common solid-state reaction when carbon and nitrogen contents fell below a critical threshold. Residual δ ferrite was found to be more susceptible to σ-phase precipitation; this type of precipitation occurred via two mechanisms that depended on the concentration profiles of δ-ferrite stabilizing elements induced by previous thermomechanical processing: direct σ precipitation (δ→σ) along the periphery of δ islands followed by a eutectoid decomposition (δ→σ+γ2) within these islands. Both simulations and experiments revealed that the σ phase at γ GB contained higher amounts of Mo and Ni, while σ within δ ferrite possessed higher contents of Fe and Cr. Finally, the simulated time–temperature–precipitation diagrams for the σ phase in residual δ ferrite were found to be in very good agreement with the experimental ones and comparable to those observed in duplex stainless steels.
Hemodialysis has a detrimental effect on fat-free mass (FFM) and muscle strength over time. Thus, we aimed to evaluate the effect of creatine supplementation on the body composition and ...Malnutrition-Inflammation Score (MIS) in patients with chronic kidney disease (CKD) undergoing hemodialysis. An exploratory 1-year balanced, placebo-controlled, and double-blind design was conducted with hemodialysis patients (≥18 years). The creatine group (CG) received 5 g of creatine monohydrate and 5 g of maltodextrin per day and the placebo group (PG) received 10 g of maltodextrin per day. MIS and body composition were analyzed at three time points: pre, intermediate (after 6 months), and post (after 12 months). After 6 months, 60% of patients on creatine experienced an increase in FFM compared to a 36.8% increase for those on placebo. Moreover, 65% of patients on creatine increased their skeletal muscle mass index (SMMI) compared to only 15.8% for those on placebo. Creatine increased intracellular water (ICW) in 60% of patients. MIS did not change after the intervention. In the CG, there was an increase in body weight (
= 0.018), FFM (
= 0.010), SMMI (
= 0.022). CG also increased total body water (pre 35.4 L, post 36.1 L;
= 0.008), mainly due to ICW (pre 20.2 L, intermediate 20.7 L, post 21.0 L;
= 0.016). Long-term creatine supplementation in hemodialysis patients did not attenuate the MIS, but enhanced FFM and SMMI, which was likely triggered by an increase in ICW.
Purpose
Patients with oligo-metastatic disease (OMD) can be safely treated with Stereotactic Radiation Therapy (SRT). Further disease progression is common in these patients. In most cases, patients ...relapse again with oligo-metastases, however some can experience a poly-progression after a local ablative treatment (LAT). The purpose of this study was to retrospectively identify factors associated with poly-progression in patients receiving SRT for OMD.
Methods
Data from a monocentric database were retrospectively analyzed. Patients treated with SRT for OMD and who developed progression after LAT were selected. Patients were categorized as oligo- or poly-progressive according to the number of new/progressing metastases (≤ or > 5). Herein, we analyzed data about patients’ characteristics, oligo-metastatic presentation and radiation treatment characteristics to evaluate their relationship with progression type.
Results
From 2013 to 2021, data on 700 patients progressing after LAT were analyzed. Among them, 227 patients (32.4%) experienced a poly-progression; the median time to poly-progression was 7.72 months (range 1–79.6). Five variables associated with poly-progression were found to be statistically significant in the univariate analysis: performance status (
p
< 0.001), site of the primary tumor (
p
= 0.016), ablative dose (
p
= 0.002), treated site (
p
= 0.002), single or double organ (
p
= 0.03). Of those, all but the number of involved organs retained their significant predictive value on the multivariate analysis.
Conclusion
Our study identified four independent factors associated with poly-progression in patients with OMD receiving SRT. Our data may support comprehensive characterization of OMD, better understanding of factors associated with progression.
The hardening and the embrittlement under neutron irradiation of an A508 type RPV steel considering three different microstructures (bainite, bainite-martensite and martensite)have been investigated ...These microstructures were obtained by quenching after autenitization at 1100 °C. The irradiation induced hardening appears to depend on microstructure and is correlated to the yield stress before irradiation. The irradiation induced embrittlement shows a more complex dependence. Martensite bearing microstructures are more sensitive to non hardening embrittlement than pure bainite. This enhanced sensitivity is associated with the development of intergranular brittle facture after irradiation; the pure martensite being more affected than the bainite-martensite. It is of interest to note that this mixed microstructure appears to be more embrittled than the pure bainitic or martensitic phases in terms of temperature transition shift. This behaviour which could emerge from the synergy of the embrittlement mechanisms of the two phases needs further investigations. However, the role of microstructure on brittle intergranular fracture development appears to be qualitatively similar under neutron irradiation and thermal ageing.
Background
Recurrent Clostridium difficile infection (CDI) represents a significant burden on the healthcare system and is associated with poor outcomes in hematopoietic stem cell transplant (HSCT) ...patients. Data are limited evaluating recurrence rates and risk factors for recurrence in HSCT patients.
Methods
HSCT patients who developed CDI between January 2010 and December 2012 were divided into 2 groups: non‐recurrent CDI (nrCDI) and recurrent CDI (rCDI). Risk factors for rCDI were compared between groups. Rate of recurrence in HSCT patients was compared to that in other hospitalized patients.
Results
CDI was diagnosed in 95 of 711 HSCT patients (22 rCDI and 73 nrCDI). Recurrence rates were similar in HSCT patients compared with other hospitalized patients (23.2% vs. 22.9%, P > 0.99). Patients in the rCDI group developed the index case of CDI significantly earlier than the nrCDI group (3.5 days vs. 7.0 days after transplant, P = 0.05). On univariate analysis, patients with rCDI were more likely to have prior history of CDI and neutropenia at the time of the index CDI case. Neutropenia at the time of the index CDI case was the only independent predictor of rCDI (78.8 vs. 34.8%, P = 0.006) on multivariate analysis.
Conclusions
The rate of rCDI was similar between HSCT and other hospitalized patients, and the majority of patients developed the index case of CDI within a week of transplantation. Neutropenia at the index CDI case may be associated with increased rates of rCDI.
Background/Objectives
An increase in fat mass is accompanied by a loss of muscle mass and function in chronic kidney disease. However, no studies in haemodialysis (HD) patients have investigated the ...relationship between fat mass and sarcopenia. The primary aim of this study is to assess the prevalence of sarcopenia, while the secondary aim is to verify the association between the fat mass percentage and SARC-F and SARC-F combined with calf circumference (SARC-F+CC) in elderly HD patients.
Subjects/Methods
A cross-sectional study enrolled 96 HD older patients (male, n = 66). SARC-F ≥4 is used to define the muscle function loss, whereas SARC-F ≥6 or SARC-F ≥11 (with the calf circumference added) are the thresholds to diagnose sarcopenia. The fat mass percentage is obtained using bioelectrical impedance analysis.
Results
We found that 37.5% had a risk of muscle function loss due to SARC-F ≥4, 21.8% risk of sarcopenia using the SARC-F ≥6, and when using CC, the prevalence of risk of sarcopenia increased to 41.6% according to SARC-F+CC ≥11. In addition, there was an association between adiposity and sarcopenia for SARC-F ≥6 (OR: 1.25, p= 0.028) and SARC-F+CC ≥11 (OR: 1.25, p= 0.0003), but not with muscle function loss (SARC-F ≥4).
Conclusion
In conclusion, we found that 37.5% of HD patients had a risk of muscle function loss and 21–41% presented sarcopenia, depending on the cut-off point used. In addition, higher adiposity was associated with an increased likelihood of having sarcopenia by 25%.
Austenite grain size has been experimentally determined for various austenitization temperatures and times in a 2.25Cr-1Mo vanadium-free steel. Three grain growth regimes were highlighted: limited ...growth occurs at lower temperatures 1193 K (920 °C) and 1243 K (970 °C); parabolic growth prevails at higher temperatures 1343 K (1070 °C) and 1393 K (1120 °C). At the intermediate temperature of 1293 K (1020 °C), slowed down growth was observed. Classical grain growth equations were applied to the experimental results, accounting for Zener pinning and solute drag as possible causes for temperature-dependent limited growth. It was shown that Zener pinning due to AlN particles could not be responsible for limited growth, although it has some effect at lower temperatures. Instead, limited and slow growths are very likely to be the result of segregation of molybdenum atoms at austenite grain boundaries. The temperature-dependence of this phenomenon may be linked to the co-segregation of molybdenum and carbon atoms.
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